RU2479532C2 - Crude mixture for making ash-slag concrete - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to the industry of construction materials and can be used in making structures and articles from concrete based on ash-slag aggregate. The crude mixture for making ash-slag concrete, which contains an aggregate and binder, which consists of flue ash obtained from burning Kansk-Achinsk brown coal at TPP-7 Bratsk, Irkutsk region, and liquid glass made from large-tonnage wastes from production of ferrosilicium at the Bratsk Ferroalloy Plant - microsilica, contains flue ash which consists of 25% field I flue ash, which is characterised by packed density p_n=830-860 kg/m³ and 6.8-7.2% residue at sieve No.0008, and 75% field II flue ash, which is characterised by packed density p_n=710-750 kg/m³ and 1.3-2.0% residue at sieve No.0008, the aggregate is an ash-slag mixture from Irkutsk TPP-6, Bratsk, which is obtianed from burning brown coal from KATEK Irsha-Borodino Coal Strip Mine, with packed density of the ash-slag mixture ρ_n=1200-1250 kg/m³, consisting of 10% ash and 90% slag, with grain size of 0.315-5 mm, with the following ratio of grains of given fractions, %: 5 mm - 56.0, 2.5 mm - 4, 1.25 mm - 15.7, 0.63 mm - 11.1, 0.315 mm - 5.8, and moisture content of 1.5-2%, with the following ratio of components of the crude mixture, wt%: said liquid glass 16.70-18.00, said ash-slag mixture 61.50-62.50, said flue ash consisting of 25% field I flue ash and 75% field II flue ash.

EFFECT: improved strength properties of concrete.

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Description

The invention relates to the building materials industry and can be used for the manufacture of structures and concrete products based on ash and slag aggregate and allows for the efficient use of large-tonnage industrial wastes.

Known concrete mixtures, including Portland cement, as well as ashes, slags and ash and slag mixtures instead of traditional aggregates [Nanazashvili I.Kh. Building Materials, Products, and Structures: Reference Book. - M: Higher. school 1990. - p. 34].

The disadvantage of such mixtures is the use of expensive Portland cement.

The closest analogue to the described invention is a raw material mixture comprising a filler and a binder, consisting of fly ash I field and liquid glass of silica fume with silicate module n = 1 and density ρ = 1.32-1.35 g / cm ³ , and aggregate - dump ash and slag mixture with bulk density ρ = 1350-1400 kg / m ³ , humidity 2-3% and 90% consisting of slag crushed stone with a grain size of 0.315-0.5 mm and 10% from ash [RU Patent No. 2374200 C1, С04В 28/08, 28/26, 111/20, 11/27/2009, 4 pp.].

The disadvantages of the described raw mix are the low strength characteristics of concrete made from this raw mix, which limits the use of the resulting concrete.

The problem solved by the invention is to improve the quality of the raw mix.

The technical result is an increase in the strength characteristics of concrete.

The specified technical result in the implementation of the invention is achieved by the fact that the raw material mixture for the preparation of ash and slag concrete includes a filler and a binder, consisting of fly ash obtained from burning brown Kansk-Achinsk coal at TPP-7 in Bratsk, Irkutsk region, and liquid glass made from bulk waste production of ferrosilicon of the Bratsk ferroalloy plant - silica fume; it contains fly ash, consisting of 25% fly ash of the I field, characterized by a bulk density ρ _n = 830-860 kg / m ³ and a residue on sieve No. 008 of 6.8-7.2%, and 75% - from fly ash of the II field, characterized by a bulk density ρ _n = 710-750 kg / m ³ and a sieve residue No. 008 of 1.3-2.0%, as a filler - dump ash and slag mixture of the Irkutsk TPP-6 g. Bratsk obtained from burning brown coal from KATEK Irsha-Borodinsky coal mine with a bulk density of ash-slag mixture ρ _n = 1200-1250 kg / m ³ , consisting of 10% ash and 90% slag, with a grain size of 0.315-5 mm with the ratio Research Institute of Grain Fractions,%:

fr. 5 mm - 56.0;

FR 2.5 mm - 11.4;

FR.1.25 mm - 15.7;

FR. 0.63 mm - 11.1;

fr. 0.315 mm - 5.8,

and humidity of 1.5-2% in the following ratio of components of the raw material mixture, wt.%:

The specified liquid glass is -16.70-18.00;

The specified ash and slag mixture is 61.50-62.50;

The specified fly ash, consisting of 25% of fly ash of the first field and 75% of fly ash of the second field - the rest.

The raw material mixture for the preparation of concrete was prepared as follows.

25 wt.% Fly ash of the first field obtained from burning brown Kansko-Achinsk coal at TPP-7 in Bratsk, Irkutsk Region, characterized by a bulk density of 830 kg / m ³ and a residue on sieve No. 008 of 6.8%, were mixed with 75 wt.% Fly ash of the II field, also obtained from burning brown Kansk-Achinsk coal at TPP-7 in the city of Bratsk, Irkutsk region, characterized by a bulk density of 728 kg / m ³ and a sieve residue No. 008 of 2.0%. The dump ash and slag mixture of the Irkutsk TPP-6 in Bratsk was added to the ash mixture, obtained from burning KATEK’s Irsha-Borodinsky brown coal mine with a bulk density of the ash and slag mixture ρ _n = 1220 kg / m ³ , humidity 1.5% and consisting of 10 wt. .% of ash and 90 wt.% - from slag with a grain size of 0.315-5 mm, characterized by the grain composition shown in tables 4 and 5. The ratio between ash and ash-slag mixture was

Ash of the first field: Ash of the second field: Ash and slag mixture = 0.25: 0.75: 3.

The properties of the materials used are presented in tables 1-6.

After mixing the dry components, liquid silica glass with silicate module n = 1 and density ρ = 1.36 g / cm ^{3 was} added to the mixture. The mixture was mixed in a forced-action concrete mixer for 2-3 minutes. 4 × 4 × 16 cm beam samples were molded at the laboratory vibratory platform. Samples solidified in a TBO chamber at a temperature of 90 ± 5 ° С for 9 hours. After this, the steamed samples were tested for strength. Similarly prepared and tested concrete based on raw mixes of other compositions. The results are presented in table 7.

Table 1 Physical characteristics of fly ash Type of ash Bulk density, kg / m ³ True density, kg / m ³ Humidity% The residue on sieve No. 008,% Losses after calcination (P.P.P.),% I field 830-860 2547 0.7 6.8-7.2 1,1 II field 710-750 2412 0.9 1.3-2.0 1.3

table 2 The chemical composition of fly ash Type of ash 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 I field 46.6 26.9 8.8 12.7 0.2 0.6 1,6 2,3 II field 50,5 8.6 8.4 20.5 0.1 0.6 1,5 1.7

Table 3 Properties of dump ash and slag mixture Bulk density, kg / m ³ True density, kg / m ³ Humidity% Crushing Strength (Dr) Losses after calcination (P.P.P.),% 1200-1250 2695 1.5-2.0 Dr 15 2,3

Table 4 Grain composition of dump ash and slag mixture Sieve residues,% Sieve hole sizes, mm for slag for ash 5,0 2,5 1.25 0.63 0.315 0.14 and less private 50,4 10.3 14.1 10.0 5.2 10 full 50,4 60.7 74.8 84.8 90 one hundred

Table 5 Grain composition of the slag component of the waste ash and slag mixture Sieve residues,% Sieve hole sizes, mm 5,0 2,5 1.25 0.63 0.315 private 56 11,4 15.7 11.1 5.8 full 56 67.4 83.1 94.2 one hundred

Table 6 The chemical composition of the waste ash and slag mixture Type of ash and slag waste The content of components, wt.% SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ R ₂ O CaO _total CaO _St. MgO SO ₃ Ash and slag mixture 48.0 8.6 6.7 0.6 26,4 6.4 2.9 0.4 Ash component of ash and slag mixture 40.3 8.6 6.5 0.8 29.6 9,4 3.8 0.9 Slag component of ash-slag mixture 66.3 7.9 5.3 3.8 14.0 - 2.1 0.7

Analysis of the obtained data shows that concrete based on the proposed raw material mixture is characterized by sufficiently high strength indicators exceeding the strength characteristics of concrete according to the prototype.

Table 7 Test results Composition number The composition of the mixture, wt.% Material Properties The strength of the samples after TVO, MPa Aggregate - dump ash and slag mixture Microcrema Nezem liquid glass Fly ash, consisting of 25% of fly ash of the first field and 75% of fly ash of the second field Ash I field Ash II field Ash and slag mixture Bulk density, kg / m ³ The residue on sieve No. 008,% Bulk density, kg / m ³ The residue on sieve No. 008,% Bulk density, kg / m ³ The residue on sieve No. 008,% one 61.56 18.0 20,44 830 6.8 728 2.0 1220 1,5 30.1 2 62.40 16.7 20.90 841 6.9 742 1.7 1236 1.8 31.9 3 62.04 17.3 20.66 860 7.2 710 1.3 1200 1.9 38.5 four 61.50 16.9 21.60 852 7.0 736 1.4 1250 1.7 34.2 5 62.50 17.6 19.9 837 6.9 750 1.9 1245 2.0 36.8

Claims (1)

The raw material mixture for the preparation of ash and slag concrete, including aggregate and cement, consisting of fly ash obtained from burning brown Kansko-Achinsky coal at TPP-7 in the city of Bratsk, Irkutsk region, and liquid glass made from large-tonnage waste from the Bratsk ferroalloy plant ferrosilicon production - silica fume, characterized in that it contains fly ash, consisting of 25% fly ash of the first field, characterized by a bulk density ρ _n = 830-860 kg / m ³ and a residue on sieve No. 008 of 6.8-7.2% , and 75% - from fly ash II field, characterizing having a bulk density ρ _n = 710-750 kg / m ³ and a sieve residue No. 008 of 1.3-2.0%, as a filler - dump ash and slag mixture of the Irkutsk TPP-6 in Bratsk, obtained from the burning of brown coal from KATEK Irsha-Borodinsky coal mine with a bulk density of ash-slag mixture ρ _n = 1200-1250 kg / m ³ , consisting of 10% of ash and 90% of slag, with a grain size of 0.315-5 mm with a grain ratio of fractions,%:
fr. 5 mm 56.0 2.5 mm 11,4 1.25 mm 15.7 FR. 0.63 mm 11.1 fr. 0.315 mm 5.8
and humidity of 1.5-2% in the following ratio of components of the raw material mixture, wt.%:
Specified Liquid Glass 16.70-18.00 The specified ash and slag mixture 61.50-62.50 Specified fly ash consisting 25% of fly ash I field and 75% - from fly ash II field Rest