What natural raw materials are used by the building materials industry. The composition of the building materials industry, its place in the construction complex and the national economy. Allite rocks - bauxite and laterite

Ministry of Science and Education of Ukraine

Kyiv National University of Construction and Architecture

Department of Construction Materials Science

Abstract on the topic: “The use of secondary products in the manufacture of building materials”

PLAN:

1. The problem of industrial waste and the main directions for solving it

c) Fused and artificial stone materials based on slagand angry

c) Materials from forest chemical waste and wood processing

4. References

1. The problem of industrial waste and the main directions for solving it.

a) Industrial development and waste accumulation

A characteristic feature of the scientific and technical process is an increase in the volume of social production. The rapid development of productive forces causes the rapid involvement of more and more natural resources into economic circulation. The degree of their rational use, however, remains, in general, very low. Every year, humanity uses approximately 10 billion tons of mineral and almost the same amount of organic raw materials. The development of most of the world's most important minerals is proceeding faster than their proven reserves are increasing. About 70% of industrial costs come from raw materials, supplies, fuel and energy. At the same time, 10...99% of the feedstock turns into waste, discharged into the atmosphere and water bodies, polluting the earth. In the coal industry, for example, approximately 1.3 billion tons of overburden and mine rocks and about 80 million tons of coal processing waste are generated annually. The annual output of ferrous metallurgy slag is about 80 million tons, non-ferrous 2.5, thermal power plant ash and slag is 60...70 million tons, wood waste is about 40 million m³.

Industrial waste actively influences environmental factors, i.e. have a significant impact on living organisms. First of all, this relates to the composition of atmospheric air. Gaseous and solid wastes enter the atmosphere as a result of fuel combustion and various technological processes. Industrial waste actively affects not only the atmosphere, but also the hydrosphere, i.e. aquatic environment. Under the influence of industrial waste concentrated in dumps, slag dumps, tailings dumps, etc., surface runoff in the area where industrial enterprises are located is polluted. The dumping of industrial waste ultimately leads to pollution of the waters of the World Ocean, which leads to a sharp decrease in its biological productivity and negatively affects the planet's climate. The generation of waste as a result of the activities of industrial enterprises negatively affects the quality of the soil. Excessive amounts of compounds that have a detrimental effect on living organisms, including carcinogenic substances, accumulate in the soil. In contaminated “sick” soil, degradation processes occur and the vital activity of soil organisms is disrupted.

A rational solution to the problem of industrial waste depends on a number of factors: the material composition of the waste, its aggregate state, quantity, technological features, etc. The most effective solution to the problem of industrial waste is the introduction of waste-free technology. The creation of waste-free production is carried out through a fundamental change in technological processes, the development of closed-cycle systems that ensure the repeated use of raw materials. With the integrated use of raw materials, industrial waste from some industries are the starting raw materials of others. The importance of integrated use of raw materials can be viewed from several aspects. Firstly, waste disposal makes it possible to solve environmental protection problems, free up valuable land occupied by dumps and sludge storage facilities, and eliminate harmful emissions into the environment. Secondly, waste largely covers the raw material needs of a number of processing industries. Thirdly, with the integrated use of raw materials, specific capital costs per unit of production are reduced and their payback period is reduced.

Of the industries that consume industrial waste, the most capacious is the construction materials industry. It has been established that the use of industrial waste can cover up to 40% of construction needs for raw materials. The use of industrial waste makes it possible to reduce the cost of producing building materials by 10...30% compared to their production from natural raw materials, saving on capital investments reaches 35...50%.

b) Classification of industrial waste

To date, there is no comprehensive classification of industrial waste. This is due to the extreme diversity of their chemical composition, properties, technological features, and conditions of formation.

All industrial waste can be divided into two large groups: mineral (inorganic) and organic. Mineral waste is of greatest importance for the production of building materials. They account for the predominant share of all waste produced by the mining and processing industries. These wastes have been studied to a greater extent than organic ones.

Bazhenov P.I. it is proposed to classify industrial waste at the time of its separation from the main technological process into three classes: A; B; IN.

Class A products (quarry residues and residues after enrichment for minerals) have the chemical and mineralogical composition and properties of the corresponding rocks. The scope of their application is determined by their state of aggregation, fractional and chemical composition, and physical and mechanical properties.

Class B products are artificial substances. They are obtained as by-products as a result of physical and chemical processes occurring at ordinary or, more often, high temperatures. The range of possible uses for these industrial wastes is wider than for class A products.

Class B products are formed as a result of physical and chemical processes occurring in dumps. Such processes can be spontaneous combustion, decomposition of slags and the formation of powder. Typical representatives of this class of waste are burnt rocks.

2. Experience in the use of waste from metallurgy, fuel industry and energy

a) Cementing materials based on slag and ashes

The bulk of waste from the production of metals and the combustion of solid fuels is formed in the form of slags and ash. In addition to slags and ashes, during metal production large quantities of waste are generated in the form of aqueous suspensions of dispersed particles - sludge.

Valuable and very common mineral raw materials for the production of building materials are burnt rocks and coal processing waste, as well as overburden rocks and ore processing waste.

The production of binding materials is one of the most effective areas of application of slag. Slag binders can be divided into the following main groups: slag Portland cement, sulfate-slag, lime-slag, slag-alkaline binders.

Slags and ashes can be considered as largely prepared raw materials. In their composition, calcium oxide (CaO) is bound in various chemical compounds, including in the form of dicalcium silicate - one of the minerals of cement clinker. A high level of preparation of the raw material mixture when using slags and ashes ensures increased furnace productivity and fuel economy. Replacing clay with blast furnace slag makes it possible to reduce the content of the lime component by 20%, reduce the specific consumption of raw materials and fuel during dry clinker production by 10...15%, and also increase the productivity of furnaces by 15%.

By using low-iron slags - blast furnace and ferrochrome - and creating reducing smelting conditions, white cements are produced in electric furnaces. Based on ferrochrome slags, by oxidizing chromium metal in the melt, clinkers can be obtained, which can be used to produce cements with an even and durable color.

Sulphate-slag cements – These are hydraulic binders obtained by joint fine grinding of granulated blast furnace slag and a sulfate hardening agent - gypsum or anhydride with a small addition of an alkaline activator: lime, Portland cement or burnt dolomite. The most widely used of the sulfate-slag group is gypsum slag cement, containing 75...85% slag, 10...15% gypsum dihydrate or anhydride, up to 2% calcium oxide or 5% Portland cement clinker. High activation is ensured by using anhydrite, calcined at a temperature of about 700º C, and high-alumina basic slags. The activity of sulfate-slag cement significantly depends on the fineness of grinding. A high specific surface area (4000...5000 cm²/g) of the binder is achieved using wet grinding. With a sufficiently high fineness of grinding in a rational composition, the strength of sulfate-slag cement is not inferior to the strength of Portland cement. Like other slag binders, sulfate-slag cement has a low heat of hydration - up to 7 days, which makes it possible to use it in the construction of massive hydraulic structures. This is also facilitated by its high resistance to soft sulfate waters. The chemical resistance of sulfate slag cement is higher than that of Portland slag cement, which makes its use especially appropriate in various aggressive conditions.

Lime-slag and lime-ash cements – These are hydraulic binders obtained by joint grinding of granulated blast furnace slag or fly ash from thermal power plants and lime. They are used for the preparation of mortars of grades no more than M 200. To regulate the setting time and improve other properties of these binders, up to 5% of gypsum stone is added during their manufacture. The lime content is 10%...30%.

Lime-slag and ash cements are inferior in strength to sulfate-slag cements. Their brands are: 50, 100, 150 and 200. The beginning of setting should occur no earlier than 25 minutes, and the end should occur no later than 24 hours after the start of mixing. When the temperature decreases, especially after 10º C, the increase in strength slows down sharply and, conversely, an increase in temperature with sufficient environmental humidity promotes intensive hardening. Hardening in air is possible only after sufficiently long hardening (15...30 days) in humid conditions. These cements are characterized by low frost resistance, high resistance to aggressive waters and low exotherm.

Slag-alkali binders consist of finely ground granulated slag (specific surface area≥3000 cm²/g) and an alkaline component - compounds of alkali metals sodium or potassium.

To obtain slag-alkaline binder, granulated slags with different mineralogical compositions are acceptable. The decisive condition for their activity is the content of a glassy phase capable of interacting with alkalis.

The properties of the slag-alkaline binder depend on the type, mineralogical composition of the slag, the fineness of its grinding, the type and concentration of its solution of the alkaline component. With a specific surface area of ​​slag of 3000...3500 cm²/g, the amount of water to form a dough of normal density is 20...30% of the binder mass. The strength of the slag-alkaline binder when testing samples from dough of normal density is 30...150 MPa. They are characterized by an intensive increase in strength both during the first month and during subsequent hardening periods. So, if the strength of Portland cement after 3 months. hardening under optimal conditions exceeds the brand name by about 1.2 times, then the slag-alkaline binder by 1.5 times. During heat and moisture treatment, the hardening process is also accelerated more intensively than during hardening of Portland cement. Under normal steaming conditions adopted in precast concrete technology, for 28 days. 90...120% of brand strength is achieved.

The alkaline components that make up the binder act as an antifreeze additive, so slag-alkaline binders harden quite intensively at subzero temperatures.

b) Fillers from slag ash waste

Slag and ash waste represent a rich raw material base for the production of both heavy and light porous concrete aggregates. The main types of aggregates based on metallurgical slag are slag crushed stone and slag pumice.

Porous aggregates are made from fuel slags and ashes, including agloporite, ash gravel, and alumina-sol expanded clay.

Effective types of heavy concrete aggregates, which are not inferior in physical and mechanical properties to the product of crushing dense natural stone materials, include cast slag crushed stone. In the production of this material, cast fire-liquid slag from slag ladles is poured in layers 200...500 mm thick onto special casting platforms or into tarpezoidal pit-trenches. When kept in open air for 2...3 hours, the temperature of the melt in the layer decreases to 800° C, and the slag crystallizes. It is then cooled with water, which leads to the development of numerous cracks in the slag layer. Slag masses at foundry sites or in trenches are mined by excavators and then crushed.

Cast slag crushed stone is characterized by high frost and heat resistance, as well as abrasion resistance. Its cost is 3...4 times lower than crushed stone made from natural stone.

Slag pumice (slows down)– one of the most effective types of artificial porous aggregates. It is obtained by porous slag melts as a result of their rapid cooling with water, air or steam, as well as exposure to mineral gas-forming agents. Of the technological methods for producing slag pumice, the most commonly used are pool, jet and hydroscreen methods.

Fuel slags and ash are the best raw materials for the production of artificial porous aggregate - agloporite. This is due, firstly, to the ability of ash and slag raw materials, as well as clayey rocks and other aluminosilicate materials, to sinter on the gratings of sintering machines, and secondly, the content of residual fuel in it, sufficient for the sintering process. Using conventional technology, agloporite is obtained in the form of crushed sand. From the ashes of thermal power plants it is possible to obtain agloporite gravel, having high technical and economic indicators.

The main feature of agloporite gravel technology is that as a result of agglomeration of raw materials, not a sintered cake is formed, but burnt granules. The essence of the technology for the production of agloporite gravel is to obtain raw ash granules with a particle size of 10...20 mm, laying them on the grates of a belt sintering machine in a layer 200...300 mm thick and heat treatment.

The production of agloprite compared to conventional agloporite production is characterized by a 20...30% reduction in process fuel consumption, lower air rarefaction in vacuum chambers and an increase in specific productivity by 1.5...3 times. Agloporite gravel has a dense surface shell and therefore, with an almost equal volumetric mass with crushed stone, differs from it in higher strength and lower water absorption. It is estimated that replacing 1 million m³ of imported natural crushed stone with Agdoport gravel from the ash of thermal power plants, only by reducing transportation costs when transporting over a distance of 500...1000 km, saves 2 million rubles. The use of agloporite based on the ashes and slags of thermal power plants makes it possible to obtain lightweight concrete grades 50...4000 with a bulk weight from 900 to 1800 kg/m³ with a cement consumption of 200 to 400 kg/m³.

Ash gravel is obtained by granulating a prepared ash and slag mixture or fly ash from thermal power plants, followed by sintering and swelling in a rotary kiln at a temperature of 1150...1250 ° C. Light concrete with approximately the same characteristics as when using aggloporite gravel is obtained using ash gravel. In the production of ash gravel, only expanding ash from thermal power plants with a fuel residue content of no more than 10% is effective.

Clay expanded clay – a product of swelling and sintering in a rotating kiln of granules formed from a mixture of clays and ash and slag waste from thermal power plants. Ash can make up from 30 to 80% of the total mass of raw materials. The introduction of a clay component improves the molding properties of the charge and promotes the burning of coal residues in the ash, which makes it possible to use ash with a high content of unburned fuel.

The volumetric mass of alumina-sol expanded clay is 400..6000 kg/m³, and the compressive strength in a steel cylinder is 3.4...5 MPa. The main advantages of the production of alumina-ash expanded clay compared to agloporite and ash gravel are the possibility of using thermal power plant ash from dumps in a wet state without the use of drying and grinding units and a simpler method of forming granules.

c) Fused and artificial stone materials based on slag and ashes

The main areas of processing metallurgical and fuel slags, as well as ashes, along with the production of binders, fillers and concrete based on them, include the production of slag wool, cast materials and slag stones, ash ceramics and sand-lime bricks.

Slag wool- a type of mineral wool that occupies a leading place among thermal insulation materials, both in terms of production volume and in terms of construction and technical properties. Blast furnace slag has found the greatest use in the production of mineral wool. Using slag instead of natural raw materials here results in savings of up to 150 UAH. per 1 ton. To produce mineral wool, along with blast furnace, cupola, open-hearth slag and non-ferrous metallurgy slag are also used.

The required ratio of acidic and basic oxides in the charge is ensured by the use of acidic slags. In addition, acidic slags are more resistant to decay, which is unacceptable in mineral wool. An increase in silica content expands the temperature range of viscosity, i.e. temperature difference within which fiber formation is possible. The acidity modulus of slag is adjusted by introducing acidic or basic additives into the mixture.

A variety of products are cast from the melt of metallurgical and fuel slag: stones for paving roads and floors of industrial buildings, tubing, curb stones, anti-corrosion tiles, pipes. The production of slag casting began simultaneously with the introduction of the blast furnace process into metallurgy. Cast products from molten slag are more economically advantageous compared to stone casting, approaching it in mechanical properties. The volumetric mass of dense cast slag products reaches 3000 kg/m³, the compressive strength is 500 MPa.

Slag crystals– a type of glass-crystalline materials obtained by directional crystallization of glasses. Unlike other glass-ceramics, the raw materials for them are slags from ferrous and non-ferrous metallurgy, as well as coal combustion ash. Slag ceramics were developed for the first time in the USSR. They are widely used in construction as structural and finishing materials with high strength. The production of slag glass consists of melting slag glasses, forming products from them and their subsequent crystallization. The charge for glass production consists of slag, sand, alkali-containing and other additives. The most efficient use of fiery liquid metallurgical slags, which saves up to 30...40% of all heat spent on cooking.

Slag ceramics are increasingly used in construction. Sheet slag slag slabs are used to cover plinths and facades of buildings, to finish internal walls and partitions, and to make fencing for balconies and roofs. Slagwood is an effective material for steps, window sills and other structural elements of buildings. High wear resistance and chemical resistance make it possible to successfully use slag ceramics to protect building structures and equipment in the chemical, mining and other industries.

Ash and slag waste from thermal power plants can serve as depleting fuel-containing additives in the production of ceramic products based on clay rocks, as well as the main raw material for the production of ash ceramics. Fuel ashes and slags are most widely used as additives in the production of wall ceramic products. For the manufacture of solid and hollow bricks and ceramic stones, it is primarily recommended to use low-melting ash with a softening point of up to 1200 ° C. Ash and slag containing up to 10% of fuel are used as waste, and 10% or more are used as fuel-containing additives. In the latter case, it is possible to significantly reduce or eliminate the introduction of process fuel into the charge.

A number of technological methods have been developed for producing ash ceramics, where ash and slag waste from thermal power plants is no longer an additional material, but the main raw material component. Thus, with conventional equipment in brick factories, ash bricks can be made from a mass including ash, slag and sodium liquid glass in an amount of 3% by volume. The latter acts as a plasticizer, ensuring the production of products with minimal moisture, which eliminates the need for drying the raw material.

Ash ceramics are produced in the form of pressed products from a mass containing 60...80% fly ash, 10...20% clay and other additives. The products are sent for drying and firing. Ash ceramics can serve not only as a wall material with stable strength and high frost resistance. It is characterized by high acid resistance and low abrasion, which makes it possible to produce paving and road slabs and products with high durability from it.

In the production of sand-lime bricks, thermal power plant ash is used as a component of the binder or filler. In the first case, its consumption reaches 500 kg, in the second - 1.5...3.5 tons per 1 thousand pieces. bricks With the introduction of coal ash, lime consumption is reduced by 10...50%, and shale ash with a CaO+MgO content of up to 40...50% can completely replace lime in the silicate mass. Ash in lime-ash binder is not only an active siliceous additive, but also contributes to the plasticization of the mixture and increases the strength of the raw material by 1.3...1.5 times, which is especially important for ensuring the normal operation of automatic stackers.

d) Ashes and slags in road construction and insulating materials

A large-scale consumer of fuel ash and slag is road construction, where ash and ash and slag mixtures are used for the construction of underlying and lower layers of foundations, partial replacement of binders when stabilizing soils with cement and lime, as mineral powder in asphalt concretes and mortars, as additives in road cement concrete.

Ashes obtained from the combustion of coal and oil shale are used as fillers for roofing and waterproofing mastics. Ash and slag mixtures are used in road construction either unstrengthened or reinforced. Unreinforced ash and slag mixtures are used mainly as a material for the construction of underlying and lower layers of the foundations of roads of regional and local importance. With a content of no more than 16% pulverized ash, they are used to improve soil coatings subjected to surface treatment with bitumen or tar emulsion. Structural layers of roads can be made from ash and slag mixtures with an ash content of no more than 25...30%. In gravel-crushed stone bases, it is advisable to use an ash and slag mixture with a pulverized ash content of up to 50% as a compacting additive. The content of unburned coal in fuel waste from thermal power plants used for road construction should not exceed 10%.

Just like natural stone materials of relatively high strength, ash and slag waste from thermal power plants are used for the production of bitumen-mineral mixtures used to create structural layers of roads of categories 3-5. Black crushed stone is obtained from fuel slag treated with bitumen or tar (up to 2% by weight). By mixing ash heated to 170...200°C with a 0.3...2% solution of bitumen in green oil, a hydrophobic powder with a volumetric mass of 450...6000 kg/m³ is obtained. Hydrophobic powder can simultaneously perform the functions of a hydro- and heat-insulating material. The use of ashes as a filler in mastics is widespread.

e) Materials based on metallurgical sludge

Nepheline, bauxite, sulfate, white and multi-calcium sludges are of industrial importance for the production of building materials. The volume of nepheline sludge alone, suitable for use, is annually over 7 million tons.

The main application of sludge waste from the metallurgical industry is the production of clinker-free binders and materials based on them, the production of Portland cement and mixed cements. Nepheline (belite) sludge, obtained by extracting alumina from nepheline rocks, is especially widely used in industry.

Under the leadership of P.I. Bazhenov developed a technology for the production of nepheline cement and materials based on it. Nepheline cement is a product of co-grinding or thorough mixing of pre-crushed nepheline sludge (80...85%), lime or other activator, such as Portland cement (15...20%) and gypsum (4...7%). The beginning of setting of nepheline cement should occur no earlier than after 45 minutes, the end - no later than after 6 hours. after its confinement, His marks are 100, 150, 200 and 250.

Nepheline cement is effective for masonry and plaster mortars, as well as for normal and especially autoclaved concrete. In terms of plasticity and setting time, solutions based on nepheline cement are close to lime-gypsum solutions. In normal-hardening concrete, nepheline cement provides grades 100...200, in autoclaved concrete - grades 300...500 at a consumption of 250...300 kg/m³. The peculiarities of concrete based on nepheline cement are low exometry, which is important to take into account when constructing massive hydraulic structures, high adhesion to steel reinforcement after autoclave treatment, and increased durability in mineralized waters.

Close in composition to nepheline cement are binders based on bauxite, sulfate and other metallurgical sludges. If a significant part of these minerals is hydrated, in order for the astringent properties of the sludge to manifest, it is necessary to dry them in the range of 300...700° C. To activate these binders, it is advisable to introduce lime and gypsum additives.

Slurry binders belong to the category of local materials. It is most rational to use them for the manufacture of autoclave-hardening products. However, they can and will be used in mortars, finishing works, and the production of materials with organic fillers, such as fiberboard. The chemical composition of a number of metallurgical slurries allows them to be used as the main raw material component of Portland cement clinker, as well as an active additive in the production of Portland cement and mixed cements.

f) Use of burnt rocks, coal preparation waste, ore mining and beneficiation

The bulk of burnt rocks are a product of burning waste rocks accompanying coal deposits. Varieties of burnt rocks are gliezh - gilin and clay-sand rocks, burned in the bowels of the earth during underground fires in coal seams, and waste, burnt-out mine rocks.

The possibilities for using burnt rocks and coal processing waste in the production of building materials are very diverse. Burnt rocks, like other calcined clay materials, are active in relation to lime and are used as hydraulic additives in lime-pozzolanic type binders, Portland cement, pozzolanic Portland cement and autoclave materials. High adsorption activity and adhesion to organic binders allow their use in asphalt and polymer compositions. Naturally, burnt rocks burned in the bowels of the earth or in waste heaps of coal mines - mudstones, siltstones and sandstones - are of a ceramic nature and can be used in the production of heat-resistant concrete and porous aggregates. Some burnt rocks are light non-metallic materials, which leads to their use as fillers for lightweight mortars and concretes.

Coal preparation waste is a valuable type of mineralogy raw material, mainly used in the production of ceramic wall materials and porous aggregates. The chemical composition of coal enrichment waste is close to traditional clayey raw materials. The role of a harmful impurity in them is sulfur contained in sulfate and sulfide compounds. Their calorific value varies widely - from 3360 to 12600 kJ/kg and more.

In the production of wall ceramic products, coal enrichment waste is used as a lean or burnable fuel additive. Before being introduced into the ceramic charge, the lump waste is crushed. Pre-crushing is not required for sludge with particle sizes less than 1mm. The sludge is pre-dried to a moisture content of 5...6%. The addition of waste when producing bricks using the plastic method should be 10...30%. The introduction of the optimal amount of fuel-containing additive as a result of more uniform firing significantly improves the strength characteristics of products (up to 30...40%), saves fuel (up to 30%), eliminates the need to introduce coal into the charge, and increases the productivity of furnaces.

It is possible to use coal enrichment sludge with a relatively high calorific value (18900...21000 kJ/kg) as a process fuel. It does not require additional crushing, is well distributed throughout the charge when poured through the fuel holes, which promotes uniform firing of products, and most importantly, it is much cheaper than coal.

From some types of coal enrichment waste it is possible to produce not only agloporite, but also expanded clay. A valuable source of non-metallic materials are associated rocks from mining industries. The main direction of recycling of this group of waste is the production, first of all, of concrete and mortar aggregates, road building materials, and rubble stone.

Construction crushed stone is obtained from associated rocks during the extraction of iron and other ores. High-quality raw materials for the production of crushed stone are barren ferruginous quartzites: hornfels, quartzite and crystalline schists. Crushed stone from associated rocks during iron ore mining is obtained at crushing and screening plants, as well as through dry magnetic separation.

3. Experience in the use of waste from chemical-technological production and wood processing

a) Application of slags from electrothermal phosphorus production

Agricultural waste of plant origin is also an important source of construction raw materials. The annual output, for example, of cotton stem waste is about 5 million tons per year, and flax kernels is more than 1 million tons.

Wood waste is generated at all stages of its harvesting and processing. These include branches, twigs, tops, branches, canopies, sawdust, stumps, roots, bark and brushwood, which together make up about 21% of the total mass of wood. When processing wood into lumber, the product yield reaches 65%, the rest forms waste in the form of slabs (14%), sawdust (12%), cuttings and small items (9%). When manufacturing construction parts, furniture and other products from lumber, waste arises in the form of shavings, sawdust and individual pieces of wood - cuttings, which make up up to 40% of the mass of processed lumber.

Sawdust, shavings and lump waste are of greatest importance for the production of building materials and products. The latter are used both directly for the production of glued building products and for processing into industrial chips, and then shavings, crushed wood, and fibrous mass. A technology has been developed for obtaining building materials from bark and dun, a waste product from the production of tanning extracts.

Phosphorus slag - It is a by-product of phosphorus produced thermally in electric furnaces. At a temperature of 1300...1500°C, calcium phosphate interacts with coke carbon and silica, resulting in the formation of phosphorus and molten slag. The slag is drained from the furnaces in a fiery liquid state and granulated using the wet method. For 1 ton of phosphorus there are 10...12 tons of slag. Large chemical enterprises produce up to two million tons of slag per year. The chemical composition of phosphorus slag is close to the composition of blast furnace slag.

From phosphorus-slag melts it is possible to obtain slag pumice, cotton wool and cast products. Slag pumice is produced using conventional technology without changing the composition of phosphorus slag. It has a bulk bulk mass of 600...800 kg/m³ and a glassy, ​​finely porous structure. Phosphorus slag wool is characterized by long thin fibers and a bulk density of 80...200 kg/m³. Phosphorus-slag melts can be processed into cast crushed stone using trench technology used in metallurgical enterprises.

b) Materials based on gypsum-containing and ferrous waste

The building materials industry's demand for gypsum stone currently exceeds 40 million tons. At the same time, the need for gypsum raw materials can be mainly satisfied by gypsum-containing waste from the chemical, food, and forest chemical industries. In 1980, in our country, the output of waste and by-products containing calcium sulfates reached approximately 20 million tons per year, including phosphogypsum - 15.6 million tons.

Phosphogypsum - waste sulfuric acid treatment of apatites or phosphorites into phosphoric acid or concentrated phosphorus fertilizers. It contains 92...95% gypsum dihydrate with a mechanical admixture of 1...1.5% phosphorus pentoxide and a certain amount of other impurities. Phosphogypsum has the form of sludge with a moisture content of 20...30% with a high content of soluble impurities. The solid phase of the sludge is finely dispersed and more than 50% consists of particles less than 10 microns in size. The cost of transporting and storing phosphogypsum in dumps is up to 30% of the total cost of structures and operation of the main production.

In the production of phosphoric acid using the hemihydrate extraction method, the waste product is calcium sulfate phosphohemihydrate, containing 92...95% - the main component of high-strength gypsum. However, the presence of passivating films on the surface of the hemihydrate crystals significantly inhibits the manifestation of the astringent properties of this product without special technological treatment.

With conventional technology, gypsum binders based on phosphogypsum are of low quality, which is explained by the high water demand of phosphogypsum due to the high porosity of the hemihydrate as a result of the presence of large crystals in the feedstock. If the water requirement of ordinary building gypsum is 50...70%, then to obtain a test of normal density from phosphogypsum binder without additional processing, 120...130% of water is required. The construction properties of phosphogypsum and the impurities contained in it have a negative effect. This influence is somewhat reduced by grinding phosphogypsum and forming products using the vibration laying method. In this case, the quality of phosphogypsum binder increases, although it remains lower than that of building gypsum from natural raw materials.

At MISS, based on phosphogypsum, a composite binder with increased water resistance was obtained, containing 70...90% α-hemihydrate, 5...20% Portland cement and 3...10% pozzolanic additives. With a specific surface of 3000...4500 cm²/g, the water requirement of the binder is 35...45%, setting begins in 20...30 minutes, ends in 30...60 minutes, the compressive strength is 30...35 MPa, the softening coefficient is 0.6...0 ,7. waterproof binder is obtained by hydrothermal treatment in an autoclave of a mixture of phosphogypsum, Portland cement and additives containing active silica.

In the cement industry, Phosphogypsum is used as a mineralizer during clinker firing and instead of natural gypsum as an additive to regulate the setting of cement. The addition of 3...4% to the sludge allows you to increase the clinker saturation coefficient from 0.89...0.9 to 0.94...0.96 without reducing the productivity of the furnaces, increase the durability of the lining in the sintering zone due to the uniform formation of a stable coating and obtain easily grindable clinker. The suitability of phosphogypsum for replacing gypsum when grinding cement clinker has been established.

The widespread use of phosphogypsum as an additive in cement production is possible only when it is dried and granulated. The moisture content of granulated phosphogypsum should not exceed 10...12%. The essence of the basic phosphogypsum granulation scheme is to dehydrate part of the original phosphogypsum sludge at a temperature of 220...250 ° C to the state of soluble anhydride, followed by mixing it with the rest of the phosphogypsum. When phosphoanhydride is mixed with phosphogypsum in a rotating drum, the dehydrated product is hydrated by the free moisture of the starting material, resulting in solid granules of phosphogypsum dihydrate. Another method of granulating phosphogypsum is also possible - with the strengthening additive of pyrite cinders.

In addition to the production of binders and products based on them, other ways of recycling gypsum-containing waste are known. Experiments have shown that adding up to 5% phosphogypsum to the charge during brick production intensifies the drying process and helps improve the quality of products. This is explained by the improvement of the ceramic-technological properties of clay raw materials due to the presence of the main component of phosphogypsum - calcium sulfate dihydrate.

The most widely used of ferrous wastes is pyrite cinders. In particular, in the production of Portland cement clinker they are used as a corrective additive. However, cinders consumed in the cement industry constitute only a small part of their total output in sulfuric acid plants that consume sulfur pyrites as the main feedstock.

A technology for the production of high-iron cements has been developed. The starting components for the production of such cements are chalk (60%) and pyrite cinders (40%). The raw material mixture is fired at a temperature of 1220…1250º C. High-iron cements are characterized by normal setting times when up to 3% gypsum is added to the raw material mixture. Their compressive strength under conditions of water and air-moist hardening for 28 days. corresponds to grades 150 and 200, and when steamed in an autoclave it increases by 2...2.5 times. High-iron cements are non-shrinking.

Pyrite cinders in the production of artificial concrete aggregates can serve as both an additive and the main raw material. The addition of pyrite cinders in an amount of 2...4% of the total mass is introduced to increase the gas-forming ability of clays when producing expanded clay. This is facilitated by the decomposition of pyrite residues in cinders at 700...800º C with the formation of sulfur dioxide and the reduction of iron oxides under the influence of organic impurities present in clay raw materials, with the release of gases. Ferrous compounds, especially in ferrous form, act as fluxes, causing liquefaction of the melt and a decrease in the temperature range of changes in its viscosity.

Iron-containing additives are used in the production of ceramic wall materials to reduce the firing temperature, improve quality and improve color characteristics. Positive results are obtained by preliminary calcination of cinders to decompose impurities of sulfides and sulfates, which form gaseous products during firing, the presence of which reduces the mechanical strength of products. It is effective to introduce 5...10% cinders into the charge, especially in raw materials with a low amount of flux and insufficient sintering.

In the production of facade tiles using semi-dry and shlinker methods, calcined cinders can be added to the mixture in an amount of 5 to 50% by weight. The use of cinders makes it possible to produce colored ceramic facade tiles without additionally introducing chamotte into the clay. At the same time, the firing temperature of tiles made of refractory and refractory clays is reduced by 50...100° C.

c) Materials from forest chemical waste and wood processing

For the production of building materials, the most valuable raw materials from chemical industry waste are slag from the electrothermal production of phosphorus, gypsum-containing and lime waste.

Waste from winter-technological production includes worn rubber and secondary polymer raw materials, as well as a number of by-products from construction materials enterprises: cement dust, sediments in water treatment devices of asbestos-cement enterprises, broken glass and ceramics. Waste accounts for up to 50% of the total mass of processed wood, most of it is currently burned or disposed of.

Construction materials enterprises located near hydrolysis plants can successfully utilize lignin, one of the most capacious wood chemical wastes. The experience of a number of brick factories allows us to consider lignin an effective burn-out additive. It mixes well with other components of the charge, does not impair its forming properties and does not complicate cutting the timber. The greatest effect of its use occurs when the quarry moisture content of the clay is relatively low. Lignin pressed into raw materials does not burn when dried. The combustible part of lignin completely evaporates at a temperature of 350...400º C, its ash content is 4...7%. To ensure the standard mechanical strength of ordinary clay bricks, lignin should be introduced into the forming charge in an amount of up to 20...25% of its volume.

In the production of cement, lignin can be used as a plasticizer of raw sludge and an intensifier for grinding the raw mixture and cement. The dosage of lignin in this case is 0.2…0.3%. The liquefying effect of hydrolytic lignin is explained by the presence of phenolic substances in it, which effectively reduce the viscosity of limestone-clay suspensions. The effect of lignin during grinding is mainly to reduce the adhesion of small fractions of the material and their adhesion to the grinding media.

Wood waste without preliminary processing (sawdust, shavings) or after grinding (chips, crushed wood, wood wool) can serve as fillers in building materials based on mineral and organic binders; these materials are characterized by low bulk density and thermal conductivity, as well as good workability. Impregnation of wood fillers with mineralizers and subsequent mixing with mineral binders ensures the biostability and fire resistance of materials based on them. General disadvantages of wood-filled materials are high water absorption and relatively low water resistance. According to their purpose, these materials are divided into thermal insulation and structural and thermal insulation.

The main representatives of the group of materials based on wood fillers and mineral binders are wood concrete, fiberboard and sawdust concrete.

Arbolit - lightweight concrete on aggregates of plant origin, pre-treated with a mineralizer solution. It is used in industrial, civil and agricultural construction in the form of panels and blocks for the construction of walls and partitions, floor slabs and building coverings, heat-insulating and sound-proofing slabs. The cost of buildings made of wood concrete is 20...30% lower than those made of brick. Arbolite structures can be operated at a relative indoor air humidity of no more than 75%. At high humidity, a vapor barrier layer is required.

Fibrolite unlike wood concrete, it includes wood wool as a filler and at the same time a reinforcing component - shavings from 200 to 500 mm long, 4...7 mm wide. and thickness 0.25...0.5 mm. Wood wool is obtained from non-commercial wood of coniferous, less commonly, deciduous trees. Fiberboard is characterized by high sound absorption, easy workability, nailability, and good adhesion to the plaster layer and concrete. The technology for the production of fiberboard includes the preparation of wood wool, its treatment with a mineralizer, mixing with cement, pressing of the boards and their heat treatment.

Sawdust concrete – This is a material based on mineral binders and sawdust. These include xylolite, xyloconcrete and some other materials similar to them in composition and technology.

Xylolite is an artificial building material obtained by hardening a mixture of magnesium binder and sawdust, mixed with a solution of magnesium chloride or sulfate. Xylolite is mainly used for installing monolithic or prefabricated floor coverings. The advantages of xylolite floors are a relatively low heat absorption coefficient, hygiene, sufficient hardness, low abrasion, and the possibility of a variety of colors.

Xyloconcrete - a type of lightweight concrete, the filler of which is sawdust, and the binder is cement or lime and gypsum; xyloconcrete with a volumetric mass of 300...700 kg/m³ and a compressive strength of 0.4...3 MPa is used as thermal insulation, and with a volumetric mass of 700...1200 kg /m³ and compressive strength up to 10 MPa - as a structural and thermal insulation material.

Laminated wood is one of the most effective building materials. It can be layered or made from veneer (plywood, laminated plastic); massive from lump waste from sawmilling and woodworking (panels, panels, beams, boards) and combined (joint slabs). The advantages of laminated wood are low bulk density, water resistance, and the ability to produce complex-shaped products and large structural elements from small-sized materials. In glued structures, the influence of anisotropy of wood and its defects is weakened, they are characterized by increased clay resistance and low flammability, and are not subject to shrinkage and warping. Glued laminated wood structures often successfully compete with steel and reinforced concrete structures in terms of time and labor costs during the construction of buildings, and resistance during the construction of an aggressive air environment. Their use is effective in the construction of agricultural and industrial enterprises, exhibition and trade pavilions, sports complexes, prefabricated buildings and structures.

Chipboards – This is a material obtained by hot pressing of crushed wood mixed with binders - synthetic polymers. The advantages of this material are the uniformity of physical and mechanical properties in various directions, relatively small linear changes at variable humidity, and the possibility of high mechanization and automation of production.

Building materials based on some wood waste can be produced without the use of special binders. Wood particles in such materials are bonded as a result of the convergence and interweaving of fibers, their cohesive ability and physicochemical bonds that arise during the processing of the press mass at high pressure and temperature.

Fiberboards are produced without the use of special binders.

Fiberboards – a material formed from a fibrous mass followed by heat treatment. Approximately 90% of all fibreboards are made from wood. The raw materials are non-commercial wood and waste from sawmills and woodworking industries. Boards can be obtained from the fibers of bast plants and from other fibrous raw materials that have sufficient strength and flexibility.

The group of wood plastics includes: Wood laminates– a material made from veneer sheets impregnated with a resole-type synthetic polymer and glued together as a result of thermal pressure treatment, lignocarbohydrate and piezothermoplastics produced from sawdust by high-temperature processing of the press mass without the introduction of special binders. The technology of lignocarbohydrate plastics consists of preparing, drying and dosing wood particles, molding the carpet, and cold pressing it , hot pressing and cooling without releasing pressure. The scope of application of lignocarbohydrate plastics is the same as that of wood fiber and particle boards.

Piezothermoplastics can be made from sawdust in two ways - without pre-treatment and with hydrothermal treatment of the raw materials. According to the second method, conditioned sawdust is processed in autoclaves with steam at a temperature of 170...180º C and a pressure of 0.8...1 MPa for 2 hours. The hydrolyzed press mass is partially dried and, at a certain humidity, is successively subjected to cold and hot pressing.

Floor tiles with a thickness of 12 mm are produced from piezothermoplastics. The starting raw materials can be sawdust or crushed coniferous and deciduous wood, flax or hemp fire, reeds, hydrolyzed lignin, and dun.

d) Disposal of own waste in the production of building materials

The experience of enterprises in the Crimean Autonomous Republic that develop limestone-shell rock to produce wall piece stone shows the effectiveness of producing shell-concrete blocks from stone sawing waste. The blocks are formed in horizontal metal molds with hinged sides. The bottom of the mold is covered with a shell rock solution 12..15 mm thick to create an internal textured layer. The form is filled with coarse-pored or fine-grained shell concrete. The texture of the outer surface of the blocks can be created with a special solution. Shell-concrete blocks are used for laying foundations and walls in the construction of industrial and residential buildings.

In the production of cement, as a result of the processing of fine mineral materials, a significant amount of dust is generated. The total amount of collected dust at cement plants can be up to 30% of the total volume of products produced. Up to 80% of the total amount of dust is emitted with gases from clinker kilns. The dust removed from the furnaces is a polydisperse powder, containing 40...70 in the wet production method, and up to 80% in the dry production method, of fractions with a size of less than 20 microns. Mineralogical studies have established that the dust contains up to 20% clinker minerals, 2...14% free calcium oxide and from 1 to 8% alkalis. The bulk of the dust consists of a mixture of baked clay and undecomposed limestone. The composition of dust depends significantly on the type of furnace, the type and properties of the raw materials used, and the method of collection.

The main direction of dust disposal at cement plants is its use in the cement production process itself. Dust from the dust settling chambers is returned to the rotary kiln along with the sludge. The main amount of free calcium oxide, alkalis and sulfuric anhydride. The addition of 5...15% of such dust to the raw sludge causes its coagulation and a decrease in fluidity. With an increased content of alkali oxides in the dust, the quality of the clinker also decreases.

Asbestos-cement waste contains large amounts of hydrated cement minerals and asbestos. When fired, as a result of dehydration of the hydrate components of cement and asbestos, they acquire astringent properties. The optimal firing temperature is in the range of 600…700º C. In this temperature range, the dehydration of hydrosilicates is completed, asbestos decomposes and a number of minerals capable of hydraulic hardening are formed. Binders with pronounced activity can be obtained by mixing thermally treated asbestos-cement waste with metallurgical slag and gypsum. Cladding tiles and floor tiles are made from asbestos-cement waste.

An effective type of binder in compositions made from asbestos-cement waste is liquid glass. Facing slabs from a mixture of dried and powdered asbestos-cement waste and liquid glass solution with a density of 1.1...1.15 kg/cm³ are produced at a specific pressing pressure of 40...50 MPa. In a dry state, these slabs have a bulk density of 1380...1410 kg/m³, a bending strength of 6.5...7 MPa, and a compressive strength of 12...16 MPa.

Thermal insulation materials can be made from asbestos-cement waste. Products in the form of slabs, segments and shells are obtained from burnt and crushed waste with the addition of lime, sand and gas-forming agents. Aerated concrete based on binders made from asbestos-cement waste has a compressive strength of 1.9...2.4 MPa and a bulk density of 370...420 kg/m³. Waste from the asbestos-cement industry can serve as fillers for warm plasters, asphalt mastics and asphalt concretes, as well as fillers for concrete with high impact strength.

Glass waste is generated both during glass production and when glass products are used at construction sites and in everyday life. The return of cullet to the main technological process of glass production is the main direction of its recycling.

One of the most effective thermal insulation materials - foam glass - is obtained from cullet powder with gas generators by sintering at 800...900°. Foam glass slabs and blocks have a volumetric mass of 100...300 kg/m³, thermal conductivity of 0.09...0.1 W and compressive strength of 0.5...3 MPa.

When mixed with plastic clays, broken glass can serve as the main component of ceramic masses. Products from such masses are made using semi-dry technology and are distinguished by high mechanical strength. The introduction of broken glass into the ceramic mass reduces the firing temperature and increases the productivity of kilns. Glass-ceramic tiles are produced from a charge containing from 10 to 70% broken glass, crushed in a ball mill. The mass is moistened to 5...7%. The tiles are pressed, dried and fired at 750...1000º C. Water absorption of the tiles is no more than 6%. frost resistance more than 50 cycles.

Broken glass is also used as a decorative material in colored plasters, ground glass waste can be used as a powder for oil paint, an abrasive for making sandpaper and as a component of glaze.

In ceramic production, waste arises at various stages of the technological process. Drying waste after the necessary grinding serves as an additive to reduce the moisture content of the initial charge. Broken clay bricks are used after crushing as crushed stone in general construction work and in the production of concrete. Crushed brick has a volumetric bulk mass of 800...900 kg/m³; it can be used to produce concrete with a bulk mass of 1800...2000 kg/m³, i.e. 20% lighter than conventional heavy aggregates. The use of crushed brick is effective for the production of coarsely porous concrete blocks with a volumetric mass of up to 1400 kg/m³. The amount of broken bricks has sharply decreased due to containerization and comprehensive mechanization of loading and unloading bricks.

4. References:

Bozhenov P.I. Integrated use of mineral raw materials for the production of building materials. – L.-M.: Stroyizdat, 1963.

Gladkikh K.V. Slags are not waste, but valuable raw materials. – M.: Stroyizdat, 1966.

Popov L.N. Construction materials from industrial waste. – M.: Knowledge, 1978.

Bazhenov Yu.M., Shubenkin P.F., Dvorkin L.I. Use of industrial waste in the production of building materials. – M.: Stroyizdat, 1986.

Dvorkin L.I., Pashkov I.A. Construction materials from industrial waste. – K.: Vyshcha School, 1989.

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Construction industry. It includes 15 sub-sectors (25 types of production), uniting about 9.5 thousand enterprises, including 2.2 thousand large and medium-sized enterprises with a total workforce of over 680 thousand people. In the total volume of industrial production, about 7% of the industry's output comes from small enterprises. In recent years, the annual growth in production of main types of building materials ranges from 7 to 30%.

The industry's products are consumed mainly in the country's domestic market. There is insignificant import of materials for general construction purposes (cement, wall materials, glass). In the group of finishing materials and products, home improvement items (linoleum, facing products made of natural stone, ceramic tiles, sanitary products), the share of imported materials reaches 20-30%. The volume of exports of domestic materials is only 4-6% of total domestic production.

The construction materials industry is one of the most fuel- and energy-intensive (more than 16% in the cost structure), as well as cargo-intensive sectors of the economy: in the total volume of cargo transportation by rail, road and water transport, transportation of construction cargo accounts for about 25%. Over 60% of the production capacity of enterprises in the building materials and construction industry is concentrated in the European part of Russia. The industry consumes 20 types of mineral raw materials and is one of the largest mining industries in the Russian economy.

Main trends in the development of the construction industry. Journal of the Higher Attestation Commission “Prospects for the innovative development of enterprises in the construction industry.” Electronic access: http://uecs.ru/uecs59-592013/item/2497-2013-11-05-10-11-10.

The construction industry is the sphere of material production and enterprises involved in the creation of construction products.

The construction industry began to include the following sectors and sub-sectors of social production:

• - Construction production (carried out by contract and economic methods);
• - Production of building materials, structures, parts;
• - Construction, road engineering, tool manufacturing, equipment repair;
• - Transport serving construction;
• - Logistics support (delivery, equipment).

Considering the complex structure of construction production, there is a fairly wide variety of approaches to determining its essence, one of them is the construction complex. The Russian Architectural and Construction Encyclopedia gives the following interpretation: “The construction complex is a set of industries, industries, organizations, characterized by close, stable economic, organizational, technical and technological connections in obtaining the final result - ensuring the production of fixed assets of the national economy.”

The construction management system in our country has undergone a long evolution, which continues to this day.

Promising markets and products of the chemical industry

In the period 2020 and until 2030, construction will be faced with the task of meeting the demand for new high-tech materials from mechanical engineering, shipbuilding, medicine, helicopter manufacturing, aircraft manufacturing, and power engineering. Developments in the space, aviation and nuclear energy sectors will also require new construction materials, composite materials, sealing materials, soundproofing materials, electrical wires and cables, and coatings. The already high demands on the technical properties of products, such as high strength, radiation resistance, corrosion resistance, resistance to high and low temperatures, and resistance to aging of materials will increase.

Currently, reinforced concrete materials occupy first place in the global construction industry. In Russia, there is a shortage and limited brand range of all types of building materials produced, creating a serious barrier to increasing the range of building structures produced.

The share of reinforced concrete products in the total volume of construction materials in Russia remains as low as in the case of automotive components. If “traditional” materials are mainly used in civil engineering, then in such sectors as the construction of bridges, railways, sections of railway tunnels, etc., reinforced concrete products have significant prospects in Russia. Thus, establishing the production of the necessary concrete products in Russia can become a significant segment of import substitution.

Precast concrete products will become widespread, replacing and surpassing in properties already established materials for the production of large-sized cabinets and small, structurally complex machine parts and mechanisms. New markets for reinforced concrete materials will be opened: in the automotive industry, shipbuilding, aerospace and energy industries, construction and electronics.

Main trends in the development of the global chemical industry

Changes in the geography of world production and consumption of construction products: the organization of new production facilities in countries and regions that are as close as possible to the growing markets for products.

The emergence of a new type of raw material for the construction industry, incl. mineral and energy resources and renewable resources.

Improving the quality of construction products will create prospects for the development of this industry.

The growing contribution of ICT at all stages of product development, production, marketing and disposal.

Increasing the energy efficiency of construction production.

A significant increase in costs for production testing and international certification of products in accordance with the principles of “Sustainable Development” and “Responsible Care” - a global voluntary initiative of construction companies that meets not only the current economic, environmental and social needs of society, but also the interests of future generations.

The list of international legislative restrictions on construction industry products is constantly growing and tightens the market access system, creating additional costs for business, because the introduction of environmental standards (in the near future, 2020-2025, the introduction of a sustainable concept of “Green Environment”) requires the replacement of technologies and the injection of significant investments.

In these conditions, the way to maintain business efficiency is not in modernization and restructuring of production in the traditional sense, but in the transition to new technological principles that make it possible to transform the raw material base, methods of conducting and computer modeling of the construction process and thus remove the growing contradictions between resource capabilities and resource intensity of production.

SWOT Analysis of the Construction Industry

Strengths	Weak sides
Rich natural resources; A sufficient number of higher educational institutions for training personnel in construction specialties; Developed infrastructure. Competent investment policy. Competitive and export-oriented products.	Low utilization of production capacities of enterprises; High degree of physical wear and tear of equipment and technologies; Insufficient capacity of the domestic market; Reduction and shortage of qualified personnel, weak influx of young people into the industry; Dependence on the process of globalization of the economy in the formation of prices and demand in the production of building materials.
Possibilities
Possibility of using existing organizations for new types of high-tech products; Implementation of innovative projects, introduction of highly effective domestic and foreign Attracting financial resources from state development institutions and other financial structures for the implementation of projects in the construction industry; Training of personnel in technological specialties for existing and new manufacturing enterprises; Creation of production facilities that do not have a significant impact on the environment.	Threat of loss of export niches in certain industry segments; Tightening in a number of foreign countries environmental legislation in the field of control over the production and turnover of construction products; High technological equipment of competitors, higher quality of products, an established marketing system of leading foreign companies in order to conquer new markets; Aging of the material and technical base in the scientific and technical field; The impact of the financial and economic crisis on the industry as a whole.

The place of the construction industry in the development of the country's economy is determined by its important role as one of the large basic complexes of the national economy of Russia, which provides many industries and agriculture with raw materials, socially oriented products, contributes to the formation of a progressive structure of production and consumption, the development of new industries and directions, ensures savings and conservation of vital resources, increasing labor productivity in related industries.

The construction industry is at the stage of maturity, the growth rate of the construction industry is slightly higher than the growth rate of GDP. Significant growth is observed only in the segments of polymer production and the creation of new advanced materials.

Industry Sensitivity Assessment

The compiled sensitivity profile shows the influence of each factor. The greatest dependence is observed on such factors as: technological changes, information technology, international cooperation, supply and sales channels, and the least - fundamental and applied research.

Construction materials industry- the basic branch of the construction complex. It is one of the most material-intensive industries. Material intensity is determined by the ratio of the quantity or cost of material resources spent on the production of products to the total volume of products. Considering that many mineral and organic wastes are close in their chemical composition and technical properties to natural raw materials, and in many cases have a number of advantages (preliminary heat treatment, increased dispersity, etc.), the use of industrial waste in the production of building materials is one of the the main directions for reducing the material consumption of this mass, large-tonnage production. At the same time, reducing the volume of developed natural raw materials and waste disposal has significant economic and environmental significance. In some cases, the use of raw materials from industrial waste dumps almost completely satisfies the industry's needs for natural resources.

The first place in terms of volume and importance for the construction industry belongs to blast furnace slag, obtained as a by-product when smelting cast iron from iron ores. Currently, blast furnace slag is a valuable raw material resource for the production of many building materials and, above all, Portland cement. The use of blast furnace slag as an active component of cement can significantly increase its output. European standards allow up to 35% granulated blast furnace slag to be added to Portland cement, and up to 80% to Portland slag cement. The introduction of blast furnace slag into the raw material mixture increases the productivity of furnaces and reduces fuel consumption by 15%. When using blast furnace slag for the production of Portland slag cement, fuel and energy costs per unit of production are reduced by almost 2 times, and production costs by 25-30%. In addition, slag as an active additive significantly improves a number of construction and technical properties of cement.

Blast furnace slag has become the raw material not only for traditional, but also for such relatively new effective materials as slag glass - products obtained by the catalytic crystallization of slag glass. In terms of strength indicators, slag ceramics are not inferior to base metals, significantly exceeding glass, ceramics, stone casting, and natural stone. Slag ceramics are 3 times lighter than cast iron and steel, they have abrasion strength 8 times higher than that of stone casting and 20-30 times than that of granite and marble.

Compared to blast furnace slags, steel smelting slags and non-ferrous metallurgy slags are still used to a much lesser extent. They are a large reserve for producing crushed stone and can be successfully used in the production of mineral wool, Portland cement and other binding materials, and autoclaved concrete.

Alumina production is characterized by a large amount of waste in the form of various sludges. Despite the differences in the chemical composition of the sludge remaining after leaching of A1203 from natural alumina-containing raw materials, they all contain 80-85% hydrated dicalcium silicate. After dehydration, this mineral has the ability to harden both at normal temperature and under conditions of heat and moisture treatment. The most large-tonnage waste from alumina production - nepheline (belite) sludge - is successfully used for the production of Portland cement and other binders, autoclave hardening materials, etc. When using nepheline sludge in the production of Portland cement, limestone consumption is reduced by 50-60%, the productivity of rotary kilns increases by 25-30%, and fuel consumption is reduced by 20-25%.

A large amount of waste in the form of ash and slag, as well as their mixtures, is generated when burning solid fuels. Their yield is: in brown coals - 10-15%, hard coals - 5-40%, anthracite - 2-30%, oil shale - 50-80%, fuel peat - 2-30%. In the production of building materials, dry ash and ash and slag mixture from dumps are usually used. The scope of application of ash and slag raw materials in the production of building materials is extremely diverse. The most significant areas of use of fuel ashes and slags are road construction, production of binders, heavy and cellular concrete, lightweight aggregates, and wall materials. In heavy concrete, ash is used mainly as an active mineral additive and microfiller, which allows reducing cement consumption by 20-30%. In lightweight concrete with porous aggregates, ash is used not only as additives that reduce cement consumption, but also as a fine aggregate, and slag as porous sand and crushed stone. Ashes and slags are also used for the production of artificial porous aggregates for lightweight concrete. In cellular concrete, ash is used as the main component or additive to reduce binder consumption.

Waste from coal mining and coal preparation is increasingly used in the construction materials industry. Coal processing plants in coal basins annually generate millions of tons of waste, which can be successfully used to produce porous aggregate and bricks. The use of coal enrichment waste as a fuel and lean additive in the manufacture of ceramic products allows reducing the consumption of equivalent fuel by 50-70 kg per 1000 pieces. bricks and improve its brand. During road construction, coal mining waste can be widely used in the construction of road pavement.

The most valuable raw materials for the building materials industry are waste from mining and non-metallic industry enterprises. There are many examples of the effective use of overburden rocks, ore processing waste, crushing screenings as raw materials for the production of binders, autoclave materials, glass, ceramics, and fractionated aggregates. Operating costs for obtaining 1 m3 of crushed stone from waste from mining enterprises are 2-2.5 times lower than for extracting it from quarries.

The chemical industry is characterized by a significant output of waste that is of interest for the production of building materials. The main ones are phosphorus slag and phosphogypsum. Phosphorus slag - waste from the sublimation of phosphorus in electric furnaces - is processed mainly into granulated slag, slag pumice and cast crushed stone. Granulated electrothermophosphorus slags are close in structure and composition to blast furnace slags and can also be used with high efficiency in the production of cements. On their basis, slag-ceramic technology has been developed. The use of phosphorus slag in the production of wall ceramics makes it possible to increase the grade of brick and improve its other properties.

The needs of the building materials industry for gypsum raw materials can be almost fully satisfied by gypsum-containing industrial waste and, first of all, phosphogypsum. To date, a number of technologies have been developed for producing construction and high-strength gypsum from phosphogypsum, but they have not yet been implemented sufficiently. This is to a certain extent facilitated by the existing pricing policy for natural raw materials, which does not fully encourage alternative secondary raw materials. In Japan, which does not have its own reserves of natural gypsum raw materials, phospho-gypsum is used almost entirely to produce a variety of gypsum products.

The use of phosphogypsum is also effective in the production of Portland cement, where it not only allows, like natural gypsum stone, to regulate the setting time of cement, but, when introduced into the raw material mixture, acts as a mineralizer that reduces the firing temperature of clinker.

A large group of effective building materials is made from wood waste and processing of other plant materials. For this purpose, sawdust, shavings, wood flour, bark, twigs, firewood, etc. are used. All wood waste can be divided into three groups: waste from the logging industry, waste from sawmills and waste from the woodworking industry.

From wood waste obtained at various stages of its processing, wood fiber and particle boards, wood concrete, xylolite, sawdust concrete, xyloconcrete, fiberboard, corolite, and wood plastics are produced. All these materials, depending on the area of ​​application, are divided into structural and thermal insulation, thermal insulation and finishing.

The use of materials based on wood waste, along with high technical and economic indicators, provides architectural expressiveness, good air exchange and indoor microclimate, and improved thermal performance.

A significant amount of waste, which can serve as secondary raw materials, is generated at the construction materials enterprises themselves. This, along with waste from the production of non-metallic materials, glass and ceramic waste, cement dust, waste from the production of mineral wool, etc. The integrated use of raw materials at most enterprises makes it possible to create waste-free technologies in which completely raw materials are processed into building materials.

Municipal waste represents significant reserves for the development of raw material potential in the production of building materials. In the advanced countries of the world, waste paper, polymer products, textiles, and glass prevail in the composition of solid household waste. We have many years of experience in the production of cardboard, fiber, construction plastic products, etc. based on these wastes.

When assessing industrial waste as a raw material for the production of building materials, it is necessary to take into account their compliance with standards for the content of radionuclides. Both natural and man-made raw materials include radionuclides (radium-226, thorium-232, potassium-40, etc.), which are sources of y-radio emissions. When radium-226 decays, a radioactive gas is released, which enters the environment. According to experts, it contributes up to 80% of the total radiation dose to people.

In accordance with building codes, depending on the concentration of radionuclides, building materials are divided into three classes:

1st class. The total specific activity of radionuclides does not exceed 370 Bq/kg. These materials are used for all types of construction without restrictions.

2nd grade. The total specific activity of radionuclides ranges from 370 to 740 Bq/kg. These materials can be used for road and industrial construction within the boundaries of populated areas and prospective development zones.

3rd grade. The total specific activity of radionuclides does not exceed 700, but below 1350 Bq/kg. These materials can be used in road construction outside populated areas - for the foundations of roads, dams, etc. Within populated areas, they can be used for the construction of underground structures covered with a layer of soil more than 0.5 m thick, where long-term presence of people is excluded.

If the value of the total specific activity of radionuclides in the material exceeds 1350 Bq/kg, the issue of the possible use of such materials is decided in each case separately in agreement with the health authorities.

The content of radionuclides in industrial waste is determined by their origin, the concentration of natural radionuclides in the feedstock. For example, in phosphogypsum of a number of countries, the concentration of radionuclides for radium-226 is in the range of 600-1500 Bq/kg, for thorium-232 - 5-7 Bq/kg and potassium-40 - 80-110 Bq/kg. Phosphogypsum produced by Russian and Ukrainian enterprises has insignificant activity, which does not exceed 1005 Bq/kg.

European standards prohibit the use in construction of materials with radiation exposure exceeding 25 nCi/kg; It is recommended that materials with radiation exposure between 10 and 25 nCi/kg be monitored and materials with radiation exposure less than 10 nCi/kg be considered non-radioactive.

Widespread recycling of waste in the production of building materials requires solving a number of organizational, scientific and technical problems. Regional cataloging of waste indicating its full characteristics is necessary. The standardization of waste as raw materials in the production of specific building materials requires development. The scale of recycling industrial waste and municipal waste will expand with the introduction of a set of technical measures to stabilize their composition and increase the degree of technological preparation (reduction of humidity, granulation, etc.).

Economic incentives, including issues of pricing, financing, and material incentives, are of great importance.

1. Cement raw materials. In 2003, the only deposit of low-magnesium investment rocks in the region, Khudoshikhinskoye, located in the Pervomaisky district, was taken into account and included in the state reserve. The deposit with reserves of about 50 million tons is capable of fully satisfying the needs of the region for the next 20-30 years for raw materials for the production of building lime and cement. Development of the deposit is hampered by the need for significant amounts of investment, difficult mining and geological conditions of production and the lack of communications in the area where the raw materials are located.

2. Gypsum, anhydrite. The region has significant proven reserves of high-quality gypsum and anhydrite, used in the production of building gypsum, Portland cement, anhydrite cement and facing boards. Of the 6 deposits of sulfate rocks with reserves of gypsum of 588.2 million tons and anhydrite of 224.5 million tons, only one is currently being developed - Bebyaevskoye in the Arzamas region. The Peshelansky gypsum plant “Dekor-1”, operating on its raw material base, annually extracts 200-220 thousand tons of gypsum stone using an underground method using an inclined adit. The raw materials are used to produce alabaster and cement. The balance reserves of gypsum at the Bebyaevskoye deposit are 70.6 million tons. The Gomzovskoye and Pavlovskoye fields in the Pavlovsk region are promising. The state reserve for underground mining includes 4 deposits - Novoselkovskoye in the Arzamas district, Annenkovskoye in the Vadsky district, Ichalkovskoye in the Perevozsky district and Pavlovskoye in the Pavlovsky district.

3. Carbonate rocks for the production of building stone and crushed stone. There are 24 deposits of this type of raw material with total reserves of 282.9 million m³ in the region. The largest are Gremyachevskoye in the Kulebaksky and Ardatovsky districts, Annenkovskoye in the Perevozsky district, Kamenishchinskoye in the Buturlinsky district, Ichalkovskoye in the Lyskovsky district, Khudoshikhinskoye in the Pervomaisky district.

5. Brick and tile raw materials. Currently, 45 deposits of brick loams and clays with reserves of 85.5 million m³ have been explored. In 2008, mining operations were carried out at 5 deposits: the Ant deposit in the Perevozsky district, the Osinovskoye deposit in the Diveevsky district, the Bogorodskoye deposit, the Krasny Rodnik in the Kulebaksky district and the Salganskoye deposit in the Krasnooktyabrsky district.

6. Expanded clay and ceramic clay. In the region, 10 deposits are taken into account for the production of expanded clay, the largest being the Pesochnenskoye and Novootnosskoye I deposits in the Dalnekonstantinovsky district, as well as Uzhovskoye on the border of the Bolsheboldinsky and Pochinkovsky districts. For the production of ceramdor, a high-strength ceramic filler for concrete and asphalt concrete, the overburden moraine loams of the Gremyachevskoe dolomite deposit were explored.

7. Sands for construction work and silicate products They are distributed almost everywhere in the region. In the region, 27 deposits of construction sands with total reserves of 134.7 million m³ have been taken into account, and 19 are being developed. Constant production is carried out at 9 fields, the largest: Varekhovskoye in the Volodarsky district, Dzerzhinskoye, Bolshoye Pikinskoye in the Borsky district, Pyatnitskoye in the Navashinsky district. The raw materials are used for the production of sand-lime bricks, wall blocks, panels, and as a concrete filler.

7. Sand and gravel material. One deposit has been explored - Volzhskoye, located on the left bank floodplain of the Volga in the Borsky district on both sides of the railway bridge. It consists of two areas with total reserves of 25.3 million m³. The deposit is not being developed due to difficult mining and technical conditions. The Sinyavskoye channel deposit of sand-gravel-crushed stone material, located in the Oka riverbed 35 km above the city of Pavlovo, is in operation. The Fokinskoye deposit of sand and gravel materials in the Vorotynsky district and the Gordinskoye deposit of boulder-gravel material in the Varnavinsky district have been explored. .

Glass sands.

There are 12 known deposits and manifestations of this raw material in the region. Glass sands from the Razinsky and Surinsky deposits in the Lukoyanovsky region are of low quality and are only suitable for the production of dark-colored glass for the production of glass containers. The Sukhobezvodnenskoye deposit in the Krasnobakovsky district with reserves of 24.93 million tons is composed of high-quality quartz sands. This deposit is unique; it is one of the largest in Europe. The development of this deposit will create 145 jobs and meet the needs of the Bor Glass Factory and metallurgical plants of the region for high-quality quartz concentrates for the production of glass and molding materials. The Pisarevskoye field in the Ardatovsky district, listed in the state reserve, is promising with reserves of 19.3 million tons.

Healing mud.

Several deposits have been explored: Neverovskoye deposit of sapropel medicinal mud (Lake Neverovo) in the Borsky district with balance reserves of 1498.1 thousand m³. Currently not in use. Shatkovo group of lakes (Chernoe, Dolgoe, Shirokoe ΙI, Svetloe) with balance reserves of 221.7 thousand m³. The “Chistoe” medicinal peat deposit in the Gorodetsky district with balance reserves of 180.1 thousand m³ is used by the “Gorodetsky” sanatorium. The Klyuchevoe deposit (Lake Klyuchevoe) in the Pavlovsk region is used by the Pavlovsk regional hospital. Balance reserves amount to 123.8 thousand m³.

The groundwater

1.Drinking and technical underground waters. The territory of the region is located within three artesian basins of non-mineralized groundwater: Volga-Sursky, Vetluzhsky and Moscow. Proven exploitable reserves amount to 2,719.028 thousand m³/day, per each resident of the region this is 2.43 m³/day. In total, there are 68 groundwater deposits in the region, the most significant are Dzerzhinskoye, Ilyinogorskoye, Borskoye, Gorodetskoye, Pyrskoye, Yuzhno-Gorkovskoye. Of these, 14 deposits have been developed. The source of water supply for cities and urban settlements is both surface and groundwater. In rural settlements, mainly groundwater is used. Most municipal districts of the region are reliably supplied with fresh groundwater reserves. The Bogorodsky, Bolshemurashkinsky, Krasnooktyabrsky, Spassky, Perevozsky districts and N. Novgorod are insufficiently provided, the Kstovsky and Pavlovsky districts are partially provided and the Sechenovsky district is not provided. In Nizhny Novgorod, domestic and drinking water supply is carried out mainly through surface water.

2. Mineral groundwater. The region is rich in mineral waters. Their natural outcrops were recorded in the Shatkovsky district in the floodplain of the Tesha River (the “Boiling Spring” spring) and in the northern regions of the region - in Shakhunsky. On the territory of the region there is a large amount of mineral waters for both table and balneological purposes - in the Green City, in the Gorodetsky, Balakhninsky districts.

3. Springs. There are more than 5 thousand springs in the region. A spring is a concentrated natural outlet of groundwater to the surface. According to the degree of mineralization, water in springs ranges from ultra-fresh to brine.

Assessing the natural resource potential as quite favorable for the settlement and economic development of the region, it is still necessary to note that for the development of basic industries, own reserves are not enough and the main industrial production operates on imported fuel and mineral resources.

building material industry

The development and location of the building materials industry is generally influenced by the following factors:

• · natural and climatic conditions;
• · presence of own raw material base;
• · professional level of those employed in the construction materials industry;
• · volumes of investments allocated for the development of the industry;
• · environmental factor;
• · scientific and technological progress (STP) and the degree of its implementation;
• · presence in the region of its own construction base and facilities;
• · level of economic development and technical equipment of the region.

Let's consider the most important factors influencing the development and location of the building materials industry.

The current geography of production “repeats,” on the one hand, the placement of developed sources of natural raw materials, which will be discussed later, and, on the other hand, the placement of capital construction.

The building materials industry is based on a very widespread raw material base, the boundaries of which are increasingly expanding under the influence of technological progress and the involvement of new resources of mineral and construction raw materials into circulation. However, the following circumstances must be taken into account.

Firstly, attention is drawn to the strong differentiation of the conditions for the development of production: different regions of the country differ from one another both in the quantity and composition of raw materials. Certain types of mineral construction raw materials are not distributed to the same extent in Russia. If, for example, brick clays, lime raw materials or concrete aggregates are found almost everywhere, then the resources of cement raw materials are more limited; Refractory clays, glass sands, gypsum and chalk are even less widespread, and material such as asbestos is represented only by isolated deposits. At the same time, any mineral construction raw material is characterized by uneven distribution. It is significant that the vast West Siberian Lowland, in different parts of which large-scale industrial construction is underway, is practically devoid of raw materials for the production of cement and other binding materials, rubble stone and crushed stone.

Within the country, there are territorial differences in the degree of provision of industry with one or another mineral construction raw material. However, each region has a unique combination of raw materials, a certain complex of minerals, being abundant in some types of raw materials and scarce in others, which is reflected in the specialization and scale of production of building materials.

Secondly, the growth of production concentration, accompanied by an increase in the capacity of enterprises, seems to limit the range of resources possible for involvement in exploitation, forcing one to focus on increasingly larger sources of mineral and construction raw materials of appropriate size.

The location of the building materials industry has a significant impact on the availability of raw materials. The dependence of production on raw material bases is explained, first of all, by the large volumetric weight and extremely low transportability of mineral construction raw materials. Thus, transporting sand or gravel by car over a distance of 50 km costs 10 times more than their extraction. Due to relatively easy development conditions and a high content of components, mineral construction raw materials are inexpensive and, as a rule, do not require preliminary enrichment. But its specific costs per unit of finished product are quite high. For example, to obtain 1 ton of cement clinker, you need to spend from 1.5 to 2.5 tons of limestone and clay, 1 ton of lime - 2 tons of limestone, 1 ton of ceramic pipes - up to 1.5 tons of clay, etc. In some cases, in addition to quantity, the quality of raw materials plays an extremely important role. In particular, cement production requires limestone and clay of certain conditions (with a minimum content of magnesium oxide in some and silicon oxide in others). In this case, the sources of limestone and clay must be geographically combined.

Finally, the fact that raw materials make up a significant part of the cost of building materials and that the waste generated during their use is not recycled once again confirms the gravitation of production towards raw material bases.

On the other hand, the location of the building materials industry largely depends on the consumer factor. Despite their widespread use and ubiquity, building materials themselves are relatively cheap and have a high volumetric weight, and as a result, low transportability. Many of them (reinforced concrete products and structures, binders, bricks) are even less transportable than the original raw materials. For example, the cost of transporting reinforced concrete products over a distance of 100 km is 25-40% of their cost. The desire to reduce transportation costs forces us to bring the production of building materials closer to the places of consumption, that is, to construction sites.

The prevalence of raw materials, the cheapness and carrying capacity of raw materials and finished products, the mass and ubiquity of their use determine the main economic and geographical feature of the building materials industry - the simultaneous attraction of production towards raw materials and the consumer.

In relation to sources of raw materials and places of consumption of finished products, enterprises in the building materials industry are divided into three types. Some of them are engaged in the extraction and pre-processing of raw materials and are geographically confined to certain natural resources. Others make materials (cement, gypsum, lime, etc.) that are then further processed. These enterprises include the full production cycle - from raw materials to finished products - and are usually associated with raw material bases. The third type is enterprises that produce finished products from pre-processed materials. They are in turn divided into enterprises with a full production cycle, which mainly gravitate towards raw materials (glass, brick and others), and into enterprises working on imported semi-finished products, located at places of consumption (concrete, reinforced concrete products and structures, and others) .

As an industry serving construction, the building materials industry serves as a link in any production-territorial complex. The gap between the production and consumption of building materials leads to a violation of the principle of achieving the highest productivity of social labor at minimal costs. Therefore, the comprehensive development of the country’s economic regions is unthinkable without the creation of local bases of construction materials. Providing construction with the necessary materials on site is a moment that accelerates the development of productive forces.

The role of individual industries in the territorial division of labor is different. In this regard, the building materials industry is represented by two groups.

The first group includes industries that produce relatively transportable products consumed in relatively small quantities by weight - cement, gypsum, lime, glass, asbestos-cement products and others. They use raw materials that are limited in distribution. There are not many enterprises in this group, but each of them often serves consumers in different areas.

The second group consists of industries that produce the most mass-produced and non-transportable products - sand, gravel, crushed stone, wall materials, reinforced concrete products and structures, and others. This group contains a large number of enterprises that use widely available raw materials and serve mainly local consumers.

Also, depending on the purpose and nature of the service, the following types of enterprises for the production of building materials can be designed:

• · inter-district (serving two or more economic regions) - factories for the production of construction and technical cement, glass, building ceramics, sanitary equipment and others;
• · district (serving the region as a whole or its individual parts) - factories for the production of reinforced concrete products for mass use, lightweight aggregates and others;
• · local (meeting the needs of a concentrated construction site) - testing grounds for the production of low-transport, large-sized products, mobile mobile enterprises and others;
• · support and rear bases - enterprises that support areas of new development and are located at some point in the developed area.

From the point of view of factors for the location of building materials industries, the following industries can be distinguished:

• · industries predominantly oriented towards raw materials - production of cement, building bricks and ceramic tiles, production of ceramics, ceramic pipes, asbestos-cement and slate products, production of glass, gypsum, lime, non-metallic building materials (gravel, crushed stone, etc.), that is, these are industries , where the specific costs of raw materials per unit of finished product are high
• · industries that are predominantly consumer oriented - the production of concrete, reinforced concrete products and structures, soft roofing, thermal insulation materials, wall materials and others, that is, these are industries where products are relatively cheap and have high volumetric weight, and as a result, low transportability.

In this regard, we can highlight the features characteristic of the building materials industry:

• · high material, fuel, energy, cargo and labor intensity of manufactured products;
• · location of most enterprises in the product consumption area;
• · broad inter-industry and intra-industry ties for production cooperation;
• · the need to meet the needs for its products in regions throughout the country.

However, the features of the building materials industry given above differ from the features of the construction complex.

Features of the construction complex:

• · availability of its own material and technical base;
• · target orientation to ensure the integrity of the complex, cooperation and specialization of labor;
• · complexity and balance of development;
• · maneuverability of individual links depending on the nature of the construction product;
• · separation of industries within the construction complex and increased interdependence.

The scientific basis for the development and distribution of production of building materials and structures in the regions of the country are regional comprehensive scientific and technological progress programs, that is, sectoral schemes for the development of the material and technical base of construction. The list of building materials included in comprehensive programs is as follows:

• · prefabricated reinforced concrete and concrete products;
• · details of large-panel and volumetric block housing construction;
• · steel structures, structures and products made of aluminum and aluminum alloys;
• · wooden structures and carpentry;
• · asbestos-cement structures and products;
• · wall blocks and building bricks;
• · non-metallic materials and porous fillers;
• · lime, gypsum, dry gypsum plaster and other local binding materials;
• · thermal insulation materials;
• · assembly blanks, assemblies and parts;
• · ready-mixed concrete, mortar, asphalt concrete;
• · commercial fittings, embedded parts