RU2470901C2 - Method of producing concrete - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to the industry of building materials and can be used when making construction products and structures from concrete. In the method of producing concrete, involving preparation of an aluminosilicate binder component, feeding an aggregate and binder components, mixing, moulding articles, ageing and solidification thereof, the aggregate used is screenings from grinding diabase with crushing strength Cr=8, packed density ρ=1560-1585 kg/m³ and fineness modulus M_f=3.6-3.9, with the following ratio of fractions, %: 5-10 mm - 15.1-47.3, 1.25-2.5 mm - 22.8-33.1, 0.315-0.63 mm - 7.8-46.2, 0.14 mm and less - 4.0-16.3, and the binder used consists of 50 wt % field II flue ash and 50 wt % waste ash-slag mixture obtained when burning brown coal from KATEK at Bratsk Thermal Power Plant, and liquid glass produced from large-tonnage ferrosilicon wastes from Bratsk Ferroalloy Plant - microsilica, with packed density of 180-200 kg/m³ and containing up to 10-15 wt % impurities, with silica modulus n=0.9-1.3 and density ρ=1.28-1.42 g/cm³ with the following ratio of components, wt %: said field II flue ash 10.75-10.94, said waste ash-slag mixture - 10.75-10.94, said diabase screenings - 64.50-65.64, said liquid glass - 12.48-14.00; preparation of the aluminosilicate component involves mixed grinding in a ball mill of ash and the waste ash-slag mixture for 20 minutes; moulding is carried out by vibration, after which ageing is carried out for 6 hours in air-dry conditions at temperature of 18-20°C, and solidification is carried out by steaming at temperature of 85°C in the 2+4+2 hour mode.

EFFECT: high strength of the concrete and shorter duration of the technological process.

8 tbl

Description

The invention relates to the building materials industry and can be used in the manufacture of building products and structures made of concrete.

A known method of obtaining building material, including dosing of quartz sand and binder components, mixing and molding samples, heat and moisture treatment, and as a binder use a binder, consisting of fly ash obtained from burning brown Kansk-Achinsk coal at CHP-7. Bratsk, Irkutsk region, and carbon-containing liquid glass made from large-tonnage waste from the production of crystalline silicon of the Bratsk Aluminum Plant - silica fume and containing up to 6-7 wt.% of dispersed carbonaceous impurities — graphite C and carborundum SiC with a silicate module n = 1 and density ρ = 1.45-1.49 g / cm ³ [RF patent No. 2130904, 1999].

The disadvantages of the described method are the relatively low strength characteristics of the building material and the use of high-quality natural material - quartz sand.

The closest analogue to the described invention is a method for producing concrete, which includes dispensing aggregate and binder components, mixing them, molding the products and hardening them followed by combined aging of the products, the screening from crushing of diabase with a bulk density of ρ = 1565-1580 kg / m ³ and the size modulus M _cr. = 4.9-4.0, and a binder is used as a binder, consisting of fly ash of the first field obtained from burning brown Kansko-Achinsk coal at TPP-7 in Bratsk, Irkutsk region, and liquid glass made from multi-tonnage ferrosilicon waste from the Bratsk ferroalloy plant - silica fume with bulk density ρ = 230-245 kg / m ³ and containing highly dispersed crystalline particles of graphite and β-modification of silicon carbide in the amount of 10-13%, with silicate module n = 1 and density ρ = 1 , 38-1.42 g / cm ³ , products are formed pre casing under a load of 7-10 MPa, and hardening is carried out in a chamber of heat-moisture treatment at a temperature of 80-85 ° C according to the regime of 1 + 3 + 3 + 3 hours, followed by combined exposure of the dismantled steamed products for 15 days in water, and then for the next 15 days - in air-dry conditions at a temperature of 15-25 ° C [patent RU No. 2376267, 12/20/2009, p.4].

The disadvantages of the described method are the relatively low strength characteristics of concrete, the duration of the hardening process.

The problem solved by the invention is to simplify the method of producing concrete.

The technical result is an increase in the strength characteristics of concrete, a reduction in the duration of the process.

The specified technical result in the implementation of the invention is achieved by the fact that the method of producing concrete includes preparing an aluminosilicate binder component, dosing the aggregate and binder components, mixing them, molding the products, keeping them and subsequent hardening; screening from crushing of diabase with crushing strength Dr = 8, bulk density ρ = 1560-1585 kg / m ³ and fineness modulus M _{cr is} used as a filler _. = 3.6-3.9 in the following ratio of fractions,%:

fr. 5-10 mm 15.1-47.3 fr. 1.25-2.5 mm 22.8-33.1 fr. 0.315-0.63 mm 7.8-46.2 fr. 0.14 mm and less 4.0-16.3

and as a binder, a binder is used, consisting of 50 wt.% of fly ash of the II field and 50 wt.% of dump ash and slag mixture obtained by burning brown coals of KATEK at the Bratsk thermal power station, and liquid glass made from multi-tonnage ferrosilicon waste from the Bratsk ferroalloy plant - silica fume, with a bulk density of 180-200 kg / m ³ and containing up to 10-15 wt.% impurities, with a silicate module n = 0.9-1.3 and density ρ = 1.28- 1.42 g / cm ³ in the following ratio of components, wt.%:

Indicated fly ash II field 10.75-10.94 Specified dump ash and slag mixture 10.75-10.94 Indicated Diabase Dropout 64.50-65.64 Specified Liquid Glass 12.48-14.00

the preparation of the aluminosilicate component is carried out by joint grinding in an ash ball mill and a waste ash and slag mixture for 20 minutes, the products are molded by vibration, and then they are kept for 6 hours in air-dry conditions at a temperature of 18-20 ° C, and hardening is carried out by steaming at temperature 85 ° С according to the 2 + 4 + 2 hours mode.

Samples for testing were prepared as follows.

In a laboratory ball mill, 50 wt.% Of ash of the II field and 50 wt.% Of waste ash and slag mixture obtained by burning brown coals of KATEK at the Bratsk TPP are milled for 20 minutes to S _beats. = 3920 cm ² / g. The properties of ash and dump ash-slag mixture are presented in tables 1-5.

Then, ground ash and ash-slag mixture are mixed with screening of diabase with crushing strength Dr = 8, bulk density ρ _n = 1560 kg / m ³ and particle size modulus _Cr. = 3.6 with particle size distribution No. 4 in the ratio "Ash II field: Ash and slag mixture: Screening diabase" = 0.5: 0.5: 3. Diabase screening properties are presented in tables 6 and 7.

Table 1 Properties of fly ash of the II field obtained by burning brown coals of KATEK at the CHPP of Bratsk Bulk density, kg / m ³ True density, kg / m ³ Humidity% The residue on sieve No. 008,% Losses after calcination (P.P.P.),% 826 2530 1.7 5,4 2.2

table 2 The chemical composition of fly ash II field The content of oxides, wt.% SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ CaO Na ₂ O K ₂ O SO ₃ MgO 50,5 8.6 8.4 20.5 0.1 0.6 1,5 1.7

Table 3 Properties of the waste ash and slag mixture obtained by burning brown coal from KATEK at a thermal power plant in Bratsk True density, kg / m ³ Bulk density, kg / m ³ Humidity% Crushing Strength (Dr) Losses after calcination (P.P.P.),% 2810 1320 1,5 Dr 12 2.7

Table 4 Granulometric composition of dump ash and slag mixture Sieve residues,% Sieve hole sizes, mm 10 5 2.5 1.25 0.63 0.315 0.14 less than 0.14 private 9 44.9 9.1 12.6 8.9 5.8 3.6 6.1 full 9 53.9 63 75.6 84.5 90.3 93.9 one hundred

Table 5 The chemical composition of the waste ash and slag mixture Mass content of components, wt.% SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ R ₂ O CaO _total. CaO _St. MgO SO ₃ 48.0 8.6 6.7 0.6 26,4 6.4 2.9 0.4

Table 6 Screening properties from crushing diabase Bulk density, kg / m ³ True density, kg / m ³ Humidity% The content of dusty and clay impurities,% Crushing Strength (Dr) 1560-1585 2800-2847 1-2 6-7 Dr 8

Table 7 Granulometric screening from crushing diabase Composition number The content of fractions,% Fineness modulus fr. 5-10 mm fr. 1.25-2.5 mm fr. 0.315-0.63 mm fr. 0.14 mm and less one 15.1 22.8 45.8 16.3 3,7 2 16.7 33.1 46.2 4.0 3.8 3 47.3 32,0 7.8 12.9 3.9 four 35,2 28.7 28.5 7.6 3.6

After that, the mixture of dry components is mixed with liquid silica glass with a bulk density of 200 kg / m ³ and containing 12 wt.% Impurities in the form of graphite and carborundum, with a silicate module of n = 1 and a density of ρ = 1.42 g / cm ³ . The mixture is mixed in a forced-action concrete mixer for 2 minutes. The samples are formed on a laboratory vibratory platform, after which the samples are kept for 6 hours in air-dry conditions at a temperature of 18-20 ° C. The hardening of the samples is carried out by steaming at a temperature of 85 ° C in the 2 + 4 + 2 hours mode. After that, test the steamed samples. The results are presented in table 8. Other samples were similarly prepared. The results are also presented in table 8.

Analysis of the data shows that the proposed method obtained sufficiently strong concrete samples. In addition, the proposed method is simpler than the prototype method, since it is completely absent for a sufficiently long period of aging of steamed products for 15 days in water, and then for the next 15 days in air-dry conditions. And finally, the proposed method allows to significantly expand the range of raw materials, since not only ash, but also dump ash and slag mixture is used as the aluminosilicate component of the binder. This, in turn, contributes to a more complete solution of environmental problems.

Claims (1)

A method of producing concrete, including the preparation of an aluminosilicate binder component, dosing of aggregate and binder components, their mixing, molding of products, their curing and subsequent hardening, characterized in that as a filler use screening from crushing of diabase with crushing strength Dr = 8, bulk density ρ = 1560-1585 kg / m ³ and particle size modulus M _cr = 3.6-3.9 in the following ratio of fractions,%:
5-10 mm 15.1-47.3 1.25-2.5 mm 22.8-33.1 0.315-0.63 mm 7.8-46.2 0.14 mm and less 4.0-16.3,
and as a binder, a binder is used, consisting of 50 wt.% of fly ash of the II field and 50 wt.% of dump ash and slag mixture obtained by burning brown coals of KATEK at the Bratsk TPP, and liquid glass made from multi-tonnage ferrosilicon waste from the Bratsk ferroalloy plant - silica fume, with a bulk density of 180-200 kg / m ³ and containing up to 10-15 wt.% impurities, with a silicate module n = 0.9-1.3 and density ρ = 1.28- 1.42 g / cm ³ in the following ratio of components, wt.%:
Indicated fly ash II field 10.75-10.94 Specified dump ash and slag mixture 10.75-10.94 Indicated Diabase Dropout 64.50-65.64 Specified Liquid Glass 12.48-14.00,
the preparation of the aluminosilicate component includes a joint grinding in an ash ball mill and a waste ash and slag mixture for 20 minutes, the products are formed by vibration, and then they are kept for 6 hours in air-dry conditions at a temperature of 18-20 ° C, and hardening is carried out by steaming at temperature 85 ° С according to the regime 2 + 4 + 2 hours