SU1033465A1 - Method for making granulated foamed glass - Google Patents

Description

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The invention relates to the production of inorganic porous granulated foam-based foam glass joints, which can be used by nony iemiH composite non-plastics, special lightweight concretes, thermal insulation drying devices and other purposes.

A known method for producing granulated foamed glass, according to which it is necessary to grind the glass with carbon-containing foaming agent, such as carbon black. Then mix the mixture by overthrowing by sintering (foaming), then crush the resulting material, process the pieces with nitrogen HALF, rinse with a boke, dry and sieve according to LI fractions.

However, as a result of these operations, pieces of foam glass with sharp edges and a crusty surface are obtained, which cannot be used as aggregates of composite foam foams. Treatment of such a lump material with nitric acid cannot be achieved by a polysheptic result, since this operation will neither lead to an improvement in the surface nor to a decrease in the bulk density.

A known method for producing granulated foam glass from glass backfills and a gasifier is obtained by dry grinding of raw materials with a post-wetting solution with bonding, granulation and agitation of the obtained granules G2.

The disadvantages of this method are the smoothness of obtaining a filler with a low bulk density (less than 120 ior / M) and a volumetric water absorption of less than 5%, as well as the need to use an additional binder in the granulation process.

The closest in technical essence and the achieved result to the invention is the method of obtaining granulated foam glass, including the use of raw material, mixing the obtained powder with sodium hydroxide solution, drying, preparing raw granules and foaming them. IfflG C J.

The disadvantages of this method are the relatively high bulk density of foam glass granules (120 2OO kg / m-), which does not allow to obtain on its basis ultra-light construction

structures with low thermal conductivity high consumption of deficient sodium hydroxide (up to 12%), which significantly increases the cost of the material.

The purpose of the invention is the bulk density of granulated glass & glass and cost reduction.

The delivered chain is achieved in that according to the method of manufacturing granulated foam glass, including a pamop of the raw material, mixing it with sodium hydroxide, drying, preparing raw granules and them. the subsequent foaming, before foaming, raw granules are treated with a solution of nitric acid.

The method is carried out as follows.

in a way.

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The initial raw materials - glass breakage (high-quality, glassware, window, etc.) - were crushed in a crushed crusher to pieces of 5-15 mm in size. Gospos washing and magnetic separation are loaded into the mill and ground to a powder with a particle size of 5 to 30 mu. The resulting piston is sifted through a sieve to separate the non-brittle particles. A foam-forming mixture is then prepared in a vice sludge with a moisture content of 30% by mixing glass powder with a 2O% solution of sodium hydroxide with the addition of the required amount of water. The consumption of sodium hydroxide is 1-4% by weight of the glass powder. After the mixture is aged for 50 to 70 hours, it is dried to a moisture content of 5-8%. To obtain raw granules, the dried mixture is crushed to pieces of 510 mm in size, which are then treated with a 20-4 O% solution of nitric acid, for example, by impregnation. The consumption of the nitric acid solution is 3-5 liters per 100 kg of raw granules. After processing, the granules are dried and poured in a rotary kiln at 825–900 C. To prevent the foaming granules from sticking together, fine material, such as ground quartz sand or slag, silica fumes and other materials is fed into the kiln with a melting point above the foaming glass foaming temperature. The consumption of dusting material is 3–8% by weight of the raw granules. After vspettva w. the granules are annealed, the dusting material is sifted out and razcel nt into fractions.

Physicomechanical evoystva-

I docked foam glass obtained

in the cited way are given in tab, 1.

Note A sort of glass breakage in a copier of 150 kg was crushed in a single ampoule with a size of 515 mm. After washing and magnetic separation, the battle is loaded into a ball mill and a mineral extract and a sieve to obtain a powder with a particle size of S-3O µm, which is then sieved through a sieve of 0.2 to 5 kg of settling out of unground particles. To the obtained glass powder (10 O kg), 12.5 kg of 2% sodium hydroxide solution are poured, 20 liters of water are added and mixed thoroughly. The consumption of sodium oxide hydrate is% by weight of the glass powder. The foamed mixture, which has a moisture content of 23%, is thus prepared as a slurry for 65 hours and then dried in a chamber dryer at 110 ° C with a moisture content of 7%. The dried mixture is crushed in a shee grinder to pieces of size 1O mm long. obtaining raw granules. After the cut-off .and the crumb. Granules are loaded into the container to pour 4 liters of a 25% aqueous solution of nitric acid; Then the granules are dried at 8 ° C for 30 minutes. Foaming of the granules is carried out in a rotary kiln at 860 ° C. To prevent the granules from sticking together, a.1d fine silica in an amount of 6 kg per 1OO kg of granules is introduced into the furnace. Next, the granules are annealed in a rotating cooler with 8 ° C and screened out of silica gel, and they are divided into fractions.

Physico-mechanical properties of nt radiated granulated foam glass are given in table. 2

This method allows to obtain granulated foam glass with a lower density of accumulators and a sufficiently high strength of the granules, while the coefficient of thermal conductivity and the water hood have rather low indices. The use of granulated foam glass with the specified properties allows you to receive. composite foam with a low density and thermal conductivity. In addition, such a granulated foam glass can be used as a filling insulation for both stationary and mobile structures of ShchI and containers.

The insignificant consumption of sodium hydroxide (1–4% instead of 12%) made it possible to reduce the consumption of scarce raw material by 3–12 times and thereby increase the cost of the finished product.

Table 1

Bulk density kg / m

Compressive strength in cylinders MPa

Watering,%

Conduction coefficient, W / (m4K)

105-115

95-110

OD5-O, 20 0.12-0.18 3-43-4

0.051

About 050

Bulk density, kg / m

Compressive strength in goshincre MPa

Absorption, on; %

Heat conductivity coefficient, W / (mK)

Tabliaiaa

100

0.13 3.9

0.050

Claims (1)

57) METHOD FOR MANUFACTURE OF GRANULATED FOAM GLASS, including psmya of the feedstock, mixing it with sodium hydroxide, drying, preparation of raw granules and their subsequent foaming, characterized in that, with a chain to reduce the bulk density of granular foam glass and reduce costs, before foaming, the raw granules are treated with a solution of nitric acid.