RU2255069C1 - Fire-resistant viscous-flow composition - Google Patents

Abstract

FIELD: manufacture of building materials.

SUBSTANCE: invention relates to fiber-reinforced easily moving and fluid compositions that can be used in building material industry as binder when manufacturing nonflammable heat-insulation and other building materials and which can play part as plugging material to close cracks, including those with elevated surface temperature. Composition contains 28-56% liquid glass, 34-65% aluminosilicate waste, 5.9-9.8% iron-containing wastes, and 0.1-0.2% finely dispersed mineral additive, wherein said aluminosilicate waste is granulated blast furnace slag or slag beads; said iron-containing wastes are those from blast-furnace production imparting alkalinity to a water extract and having specific surface 100-150 m²/kg, blast furnace dust, or ore agglomeration waste; and said finely dispersed mineral additive are wood ashes.

EFFECT: improved compaction strength, water resistance, and rheological properties without loss in fire resistance.

4 tbl, 2 ex

Description

The invention relates to compositions of dispersion-reinforced highly mobile and fluid compositions and can be used in the building materials industry as a binder in the manufacture of hardly combustible heat-insulating and other building materials, and also act as a plugging material for closing cracks, including cracks with an increased surface temperature .

Known disperse-reinforced with ferrous microparticles is a viscous flow-resistant fire-retardant composition for wood coating (see Auth. Certificate. USSR No. 1158538 A, Mcl C 04 B 28/24, publ. 05/30/85, Bull. No. 20), containing components the next time ratio, wt. %:

- liquid glass - 55 - 56

- ground asbestos with a specific surface area of 300-350 m ² / kg - 4.2 - 7.2

- cable rosin-containing oil - 0.15 - 0.18

- ground pyrite cinder with a specific surface area of 300-350 m ² / kg - 16.62 - 17.55

- ground granulated slag - the rest.

Along with the advantages of the composition, there are also disadvantages:

- low compressive strength (7-10 MPa);

- insufficient mobility and fluidity with a relatively high consumption of water glass (more than 50%), which limits the use for plugging (closing) cracks of various structures, as well as acting as a binder for the manufacture of building materials and structures;

- pyrite cinders (waste products of sulfuric acid) give the aqueous extract an acidic environment, which reduces the hydraulic activity of ground granulated slag or slag "king", and therefore, strength;

- ground asbestos - a mineral additive is among the deficient additives and reduces the mobility of the viscous fluid composition.

Another fire-resistant viscous fluid composition is known (see Aut. St. USSR No. 1188140, MKL. 04 V 28/24, publ. 10/30/85, Bull. No. 40), containing components in the following ratio, wt.%:

- liquid glass - 48 - 52

- ground blast furnace slag (aluminosilicate slag

production waste) - 22 - 25

- ground asbestos - 5 - 6

- ground sludge gas treatment blast furnaces

(iron-containing waste) - 19 - 20

- phosphate-rich enriched waste sludge

Caprolactam production filter - 1 - 2.

Along with the advantages of this composition (increased fire resistance, adhesion to a cellulose-containing surface), there are also disadvantages:

- low compressive strength (10-12 MPa);

- relatively low water resistance (softening coefficient K _size = 0.6 - 0.7);

- lack of mobility and fluidity, which limits the use of the composition as a binder for the manufacture of dispersed-fiber structural and heat-insulating, heat-insulating and other building materials with increased fire resistance, as well as the use as a plugging material for closing cracks of various structures;

- ground slurry of gas purification of blast furnaces gives the aqueous extract a neutral environment (pH is 7), which does not increase the hydraulic activity of ground granulated slag or slag "king", and therefore, increase the strength;

- ground asbestos - a mineral microfiller is among the deficient additives and, in a finely ground state, reduces the mobility or fluidity of the composition due to increased adsorption of the liquid component;

- ground sludge “Radialit-900” gives the aqueous extract an acidic environment, which negatively affects the hydraulic activity of the composition.

The objective of the invention is to increase the compressive strength, water resistance and rheological properties without loss of fire resistance.

To achieve this goal, a flame-retardant viscous fluid composition including liquid glass, ground aluminosilicate production waste, iron-containing waste and finely dispersed mineral additives, iron-containing blast furnace waste, which gives an aqueous extract alkaline environment - pH greater than 7, with a specific surface of 100 is used as iron-containing waste. -150 m ² / kg, blast furnace dust or waste from ore agglomeration, as a finely dispersed mineral additive - wood ash from burning cellulose-containing waste, as the specified aluminosilicate waste - blast furnace slag or slag "korolek" in the following ratio of components, wt.%:

water glass 28 - 56

specified ground aluminosilicate waste 34 - 65

specified iron wastes 6.9 - 9.8

specified wood ash 0.1 - 0.2

In experiments on the implementation of the proposed composition, blast furnace slag and slag “bead” were adopted with the same strength grade (M 400) with a slight difference in their activity of ± 0.5 - 1 MPa.

A preliminary determination of the brand by strength was carried out according to the method as applied to slag-alkali binders.

Accepted components in experiments on the implementation of the composition had the following characteristic properties and compositions.

1. Ground basic granulated blast furnace slag.

The specific surface is 300 m ² / kg, bulk density is 1140-1150 kg / m ³ . The basicity module is 1.05-1.1.

The chemical composition of the slag, wt.%:

- SiO ₂ - 39.4 - 40;

- Al ₂ O ₃ - 6.5 - 9.0;

- CaO - 42.26 - 43.36;

- MgO - 7.27 - 7.9;

- FeO - 0.31 - 0.32;

- MnO - 0.23 - 0.26;

- S - 1.74 - 1.92.

2. Slag “korolek” - a waste product of mineral wool production.

These are unmelted granules of aluminosilicate raw materials in the production of mineral wool. It is used as aggregate (sand) in concrete and according to the literature (see “Production of concrete and structures based on slag-alkali binders” / V.D. Glukhovsky, P.V. Krivenko, G.V. Romanina, etc. - K .: Budivelnik, 1988 - 144 p.) Can be used as an aluminosilicate base (ground) for a slag-alkali binder.

In the experiment, the slag “bead” of the Tula plant “Building Materials” was adopted, which meets the requirements of TU 5718-004-01250234-95. Hygienic certificate No. 409 dated November 30, 1994. In accordance with the requirements of TU, it is resistant to silicate decomposition if CaO does not exceed a critical value, i.e.

CaO _cr = 1.2SiO ₂ % + 0.4Al ₂ O ₃ % + 0.8MgO% + 1.7S%.

Slag “korolek” (BK) is stable if the content of FeO + MnO oxides does not exceed 3% and the content of sulfate sulfur is not more than 1.5%. In experiments on the implementation of the proposed composition adopted HQ the following chemical composition.

Table 1.
The chemical composition of the slag "king". Oxides, wt.% SiO ₂ Al ₂ O ₃ Fe ₂ O ₃ CaO MgO SO ₃ Na ₂ O + K ₂ O MnO 43.2-44.06 12.86-13.03 9.78-10.05 19.56-19.82 9.86-11.0 0.09-0.15 3.28-3.44 0

3. Liquid glass

In the experiments, liquid silicate glass with a silicate module of 2.8 - 3.1 and a density of 1.3 g / cm ^{3 was} adopted.

4. Iron-containing waste

4.1. Blast furnace dust is a waste from smelting of ordinary cast iron with a specific surface of 100-150 m ² / kg, which gives an alkaline environment to the aqueous extract.

table 2
The chemical composition of blast furnace dust OJSC Tulachermet. Oxides, wt.% SiO ₂ Al ₂ O ₃ CaO MgO FeO Fe Fe ₂ O ₃ 6.33-12.66 0.93-1.75 20.47-22.43 1.56-1.72 3.21-8.31 0.34-1.63 33.21-41.08 MnO P ₂ O ₅ SO ₃ S FROM Na ₂ O + K ₂ O TiO ₂ 0.065-0.90 0.053-0.14 1.18-1.8 0.47-0.72 16.01-18.50 1.173-0.32 1.86-2.17

4.2. Ore from sintering ore

This is a finely divided mixture, including seeding and dust from cyclones formed during the agglomeration of iron ore, i.e. fusion of ore with lime or limestone. The specific surface is 120-150 m ² / kg.

Table 3
The chemical composition of agglomeration waste. SiO ₂ Al ₂ O ₃ FeO Fe ₂ O ₃ MnO MgO P ₂ O ₅ CaO SO ₃ Na ₂ O + K ₂ O 9.14-10.2 1.47-1.5 5.67-6.5 38.0-42.05 0.15-0.17 1.7-2.1 0.13-0.14 34.94-39.07 2.7-3.3 0.3-0.6

As can be seen from paragraphs 4.1 and 4.2, the accepted waste contains at least 40% of iron-containing oxides and iron FeO + Fe ₂ O ₃ + Fe and at least 20% of alkaline and alkaline-earth oxides CaO + MgO + Na ₂ O (K ₂ O), which provide an alkaline environment for water drawing. This is facilitated by alkali-containing ash from the burning of cellulose-containing waste.

Note. It is not recommended to use the same waste from hydraulic dumps as sludge, as soluble alkaline and alkaline earth compounds are washed out by water and diffuse into the soil (pH extract is zero - the medium is neutral).

5. Ash from the burning of cellulose-containing waste (wood, bonfire made from flax, sunflower stems, cardboard, etc.)

The specific surface is 600 m ² / kg. Contains at least 20-25% K ₂ CO ₃ .

Implementation of the proposed composition of the fire-resistant viscous fluid composition.

Previously, in a laboratory ball mill, the main blast furnace slag, “Korolek” and other components accepted in a known composition were alternately crushed to a specific surface of 300 m ² / kg: asbestos, dried gas purification sludge and enriched phosphate-containing sludge from an exhausted caprolactam production filter, i.e. “Radialit-900”.

Experience 1. For the proposed composition

Five experimental dry mixtures were prepared on the basis of ground granulated slag and slag “bead” by dosing them by weight and then mixing with metered non-ground iron-containing blast furnace wastes that impart an alkaline medium to the aqueous extract (pH 8-8.5) and have a specific surface area, respectively 100, 120, 150, 200 m ² / kg. Regulation (increase) of the specific surface was carried out by adding smaller particles from the cyclones of this process to the sowing of the agglomeration process. Additionally, said ash was added to the mixture of dry powders. As iron-containing additives, blast furnace dust and seeding (particles passing through a sieve with a diameter of 0.14 mm) from the agglomeration of iron ore without or with the addition of dust from cyclones of the same process were used.

Dry mixtures, including ground aluminosilicate slag production waste, iron-containing waste and additionally introduced wood ash, were closed with liquid glass with a density of 1.3 g / cm ³ . The role of dispersed reinforcing material and at the same time microfiller was performed by iron-containing particles.

For the prepared viscous flowing mixtures, rheological properties were determined. For more viscous mixtures, mobility was measured using a Suttord viscometer — the cone spread in mm, and for more mobile mixtures, the fluidity in seconds was measured using a VZ-4 viscometer.

From the obtained mixtures, samples 16 × 4 × 4 cm in size were molded in metal molds, held until the end of setting, and then heat treated in steaming chambers according to the 2 + 6 + 2 hours regime at an isothermal holding temperature of 90 ± 5 ° С. After stripping the molds, the samples additionally hardened under normal conditions (t = 20 ± 2 ° C and 95% relative humidity) up to 28 days from the end of setting. Hardened samples were tested for water resistance, compressive strength, and fire resistance.

The compressive strength and water resistance were determined in relation to hydraulic binders, and fire resistance was determined using the “Fire Pipe” with holding in the flame of an alcohol lamp (5 min) (See L.64 “Metrology, means and methods of quality control in construction.” - M .: Stroyizdat, 1979 - 223 p.). Fire resistance was judged by the loss of mass of the hardened composite.

The test results are shown in table 4.

Experience 2. To test the properties of the known composition

Aluminosilicate waste (granulated slag and slag “korolek”), the iron-containing additive — dry sludge for gas cleaning of blast furnaces, asbestos and enriched sludge from an exhaust filter for the production of caprolactam were dosed by weight, finely ground to a specific surface of 300 m ² / kg. The ratio of components in% by weight is given in the table. The mixture of dry powders was sealed with liquid glass with a density of 1.3 g / cm ³ and a silicate module of 2.8 - 3.1. The resulting viscous-fluid mixture was molded by casting in metal molds with a size of 16 × 4 × 4 cm. After the end of setting, the products were removed and subjected to hardening, which was given in experiment No. 1. After 28 days, the hardened samples were tested for strength, water resistance, and fire resistance according to the experimental procedure No. 1.

The test results are shown in table 4.

Analysis of the results of the properties of the proposed composition in comparison with the known shows:

1. The quantitative composition of the mixture No. 2 and No. 6 does not meet the task, ie in terms of mobility (composition No. 2) and compressive strength (composition No. 6). Therefore, the compositions No. 2 and No. 6 are beyond.

2. The compositions adopted in mixtures No. 3, No. 4, No. 5, correspond to the task observed:

- increase in compressive strength by 4.08 - 56.8 MPa (by 35-85%);

- increase in mobility (by Suttard viscometer by 20 mm), i.e. by 10.25%, moreover, with a consumption of liquid glass, less by 30%;

- a decrease in flow time by 11 seconds (20%) with a liquid glass consumption of less than 10%.

3. The proposed composition relates to a composition of hydraulic hardening, therefore, with increasing consumption of water glass, the softening coefficient remains almost unchanged and remains in the range of 0.95-0.985, and the known composition relates to air hardening material of increased water resistance.

4. In terms of fire resistance, the proposed composition is similar to the claimed, because after 5 minutes of exposure to fire and when the mass of the sample is heated to a temperature of 300 ° C, the mass loss is not more than 2.5%, which is not more than known.

The physicochemical nature of increasing these parameters and properties is as follows:

1. In the inventive composition, the aluminosilicate component (ground granulated slag or slag “bead”) is quantitatively prevailing, which contributes to an increase in hydraulic activity, including with increased consumption of water glass.

An increase in hydraulic activity (strength, water resistance) is facilitated by an additional alkaline medium, which is formed as a result of dissolution of free lime contained in iron-containing wastes, including potash (K ₂ CO ₃ ) contained in this ash, i.e. loss of hydraulicity with increasing consumption of liquid glass is compensated by an increase in the alkalinity of the medium in the composition. The latter contributes to an increase in the compressive strength of the hardened composition.

2. In the known composition adopted iron-containing sludge from gas purification of the blast furnace process, which is transported by means of water to dumps and the soluble salts of alkaline and alkaline earth oxides, as well as lime, diffuse with the water into the soil. Such waste in a water extract has a neutral environment and does not contribute to increased water resistance and strength.

3. In the proposed mixture, the amount of iron-containing waste is limited to 9.8%. The latter increase fire resistance and to some extent compressive strength, which can be seen from a comparison of the composition of the mixture No. 2 and No. 3 (R _cf = 69-71 MPa) with the composition of the cinder-alkali binder No. 1, R _cf = 65.2 MPa, in which there are no iron-containing waste. However, with a further increase in the amount of liquid glass and, accordingly, with an increase in the R / N ratio of more than 0.39, a decrease in strength is observed, despite an increase in iron-containing waste.

4. The reduction of the specific surface area of iron-containing waste by about half (from 300 to 100-150 m ² / kg) provides less water demand, which contributes to an increase in mobility, fluidity and strength.

5. The addition of ash introduced into the composition of the composition has a positive effect on fire resistance and at the same time acts as a plasticizer, as the potash contained in its composition (K ₂ CO ₃ ) not only increases the alkalinity of the medium, but is also an electrolyte.

In a known composition, ground asbestos and spent filter sludge from the caprolactam production increase fire resistance, but reduce compressive strength, mobility, and fluidity, because ground asbestos and the specified sludge with a specific surface of 300 m ² / kg have high water demand, and the sludge “Radialit-900” gives the aqueous extract an acidic environment, because contains residues of phosphoric acid, which negatively affects the water resistance and compressive strength of the composition.

The proposed composition in relation to the known has the following technical and economic advantages.

1. Thermal energy and mechanical costs are reduced due to the lack of drying and fine grinding of iron-containing waste and mineral additives, as well as ash from the burning of cellulose-containing waste.

до

, т.е. на 8%.2. The arithmetic average consumption of expensive liquid glass is reduced with

before

, i.e. by 8%.

3. Utilized little-used environmentally friendly waste is disposed of: slag “korolek” and ash from the burning of waste wood, cardboard, etc. Slag “korolek” is 3–4 times cheaper than granulated slag, because It is not used as a basis in the production of slag Portland cement. Accepted ash is 5-6 times cheaper than ground asbestos.

4. The proposed mixture has wider applications, because It is not only fireproof, but also a binder of hydraulic hardening.

5. Based on these advantages in paragraphs 1 to 4, the cost of the composition is reduced by 20-25%.

Claims (1)

Flame retardant viscous flowing composition, including liquid glass, ground aluminosilicate production waste, iron-containing waste and a finely divided mineral additive, characterized in that it contains iron-containing blast furnace waste as an iron-containing waste, imparting an alkaline medium to the aqueous extract - pH greater than 7, with a specific surface of 100- 150 m ² / kg, blast furnace dust or waste from ore agglomeration, as a finely dispersed mineral additive - wood ash from the burning of cellulose-containing waste, in the quality of these aluminosilicate wastes is blast furnace slag or slag “korolek”, with the following ratio of components, wt.%: Liquid glass 28 - 56 The specified ground aluminosilicate waste 34 - 65 Indicated iron waste 6.9 - 9.8 Specified wood ash 0.1 - 0.2