SU990689A1 - Method for preparing batch for making mineral wool - Google Patents

Description

The invention relates to the production of thermal insulation and acoustic building materials and can be used in the manufacture of a mixture for the production of mineral wool. A known method of preparing a mixture for the production of mineral wool, including the grinding of raw materials, their weight dosage, mixing, and molding in the form of briquettes 11 However, since the briquettes are raw materials,. made by this method do not contain additives that ensure their heat resistance, when they are heated in the cupola, they are destroyed, and the resulting fines are partially carried away by the blast air, pollute the environment, and partially fill the voids of the charge column, interfering with the passage of blast air, which reduces the intensity -, the burning of coke and the melting capacity of the cupola decreases. The closest to the invention to the technical essence and the achieved result is the method prepared -. lazy batch for melting in a cupola in the manufacture of mineral wool, including mixing dry powdered raw materials, such as crushed stone 4-10 mm in size, hydrated, such as portland cement, and additives containing not less than 75% silica, such as ash, adding to the resulting mixture water to the state of a concrete-like test, curing in forms for 2 hours and the subsequent 3-day holding 2. However, briquettes made by a known method are not completely heat-resistant. At 1100 ° C, their strength decreases by approximately 2 times, which is accompanied by their partial destruction, corresponding excretion into the environment and a decrease in the performance of the truck. In addition, for the manufacture of briquettes, a hydraulic mortar is required, for example, Portland cement, which has a cost, as a rule, is higher than any raw material; used for the production of mineral wool. In this case, the briquettes must be kept after molding for 4 days, for which certain storage rooms are required. The purpose of the invention is to increase the productivity of the cupola and reduce environmental pollution. This goal is achieved by the fact that according to the method of preparation of the mixture to obtain mineral wool, which includes mixing raw materials, a hydraulic binder and additives, wetting and pressing, cement dust-drift of electro-filters of rotary kilns is used as a hydraulic binder, their weight is the ratio is from 1: 0.13 to 1: 2, the mixture is moistened to 10-13, and pressing is carried out under a pressure of 100200 kgf / cm. Example For the preparation of the charge, 16 kg of quartz sand, 11 kg of waste (fly ash) of expanded clay production, 13 kg of mineral wool waste (korolkov), 53 kg of waste (dust) of cement production and 7 kg of clay are taken. Suspension is prepared from hLyuy in a mixture with a solid / liquid phase ratio of 1. Quartz sand is mixed with production waste, then mixed with clay slurry and further moistened to a moisture content of charge 13. The mixture obtained is fed to a press made of silicate brick, where, under pressure of 200 kgf / cm, briquettes are pressed. PRI mme R 2. To prepare the charge, 25 kg of waste (mini-wool production, 25 kg P

Indicators

by famous

Initial

After heating to 1100 ° С

on the proposed method: method

example 1 example 2

130

150

lifO

125 waste (dust-ash) of cement production, 50 kg of clay, dried and crushed to a grain size of not more than 3 mm. All materials are mixed, moistened to 10 and pressed as in example 1 under a pressure of 100 kgf / cm. By increasing the pressure over the indicated values, briquettes with higher mechanical strength can be obtained; however, this requires more complex pressing equipment. In addition, the strength of briquettes is about 130-. 150 kgf / cm, obtained at the pressure indicated in the examples, is sufficient to melt in the cupola. Reducing the pressure does not allow to obtain the necessary strength. Also the indicated humidity is optimal for pressing. Higher humidity requires an increase in pressure values and, accordingly, a more powerful press, while at the same time a decrease in humidity does not allow obtaining the necessary strength of the briquettes. The content of components specified in the examples is optimal in terms of the strength of the briquettes, as well as from the point of view of the chemical composition of the melt and its physicochemical properties necessary for forming fine and long fibrous mineral wool. The briquettes obtained by the proposed method, immediately after production, can be melted in a cupola. To determine the thermal stability of the briquettes, a test was carried out according to the following procedure. The briquettes were heated to 1100 ° C in a muffle furnace, then cooled at a rate of not more than T C / min, then their strength was determined on a test press. These tests are shown in the table. . - awn briquettes, kgf / cm

The heat resistance of briquettes manufactured by the proposed method increases due to more intensive chemical solid-phase reactions between the cement component of the charge and clay than between the cement component of the mixture and silica.

Claims (2)

1. USSR author's certificate If 81122, cl. From 03 to 1/00,. 2. British Patent If 1529288, cl. From 03 To 1/00, 1978 (prototype).