SU1067065A1 - Method for preparing clinker of zinc production for smelting - Google Patents

Abstract

A METHOD FOR PREPARING ZINC PRODUCTION CLINKER FOR MELTING, including heating it and cooling, characterized in that, in order to reduce the cost of fuel for preparation, the clinker is heated to 1050-1150С, molded and cooled to 2p-400 s at a speed of 4-15 degrees / min and then at a speed of up to 100 degrees / min.

Description

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About the invention The invention relates to non-ferrous metallurgy, in particular, to zinc metallurgy, and can be used for the agglomeration of clinker - a product of yeltsinite zinc and raynovki before processing it in shaft furnaces. Zinc production clinker contains copper, gold, silver and is a valuable raw material for the production of these metals. According to the conditions, the existing technology on zinc, clinker plants at the exit of the roller, the furnace is subjected to a water granule, as a result of which it contains much fines (up to 85% of the class minus 10 mm). In domestic practice, clinker processing is carried out in iiiaxxHHX furnaces. The presence in the clinker of a large amount of fines makes it difficult to process it in the kiln furnaces: it reduces productivity and increases dust removal. Special preparation of clinker is required before smelting. The known method of preparing clinker for smelting by agglomeration in a mixture with copper concentrates and fluxes 11. However, the sintering process requires considerable capital and operating costs and cannot be applied to the clinker in its pure form due to the high content of combustible components — carbon and carbon dioxide. metallic iron, the burning of which leads to the heating and melting of the sintering equipment. In addition, the agglomeration process is accompanied by large emissions of harmful gases. The closest to the invention in its technical essence and the effect achieved is the method of preparing clinker for smelting, which consists in heating the clinker to 125–1300 ° C, holding it at these temperatures for 55–65 minutes, then cooling it to 950–1050 s and holding at these temperatures for 40-50 minutes 2J. The implementation of this method requires considerable fuel consumption for clinker heating and subsequent long-term storage at these temperatures. In addition, the production of clinker with a granulometric composition conforming to the technical requirements of the mine bedding is not achieved. The aim of the invention is to reduce the fuel costs for preparation. The goal is achieved in that according to the method of preparing the zinc production clinker for smelting, including heating and cooling, the clinker is heated to 1050-1150 s, molded and cooled 65 about 20p-400t at a speed of 4 -15 g rad / min and then at a speed of up to 100 deg / min. The hot clinker at the exit of the Waelz kiln has a temperature of 1050IISO C and consists of solid particles and a melt. When unloading from Weltzpech directly into molds, onto a plate conveyor, etc. clinker is easily molded. During molding, the solid particles are surrounded by the melt, which, upon cooling, crystallizes and mechanically binds (cements) the solid particles. The clinker, heated to a temperature below, is poorly molded, since the melt in such clinker is not enough to bind solid particles. At a temperature of you. 1x 1150 ° C The melt in the clinker is overheated too much and during the molding process it flows down to the bottom of the mold, the hard part, the eggs are not cemented. Cooling molded clinker Up to 200-400 ° C is conducted at an average speed of 4-15 degrees / min. This range of cooling rates was chosen for reasons of maintaining the strength of the clinker pieces. With an increase in the cooling rate above 15 deg / min, a high thermal stress arises in the pieces of clinker, which leads to cracking and, ultimately, to an increase in the yield of fine fractions. With a cooling rate of less than 4 K / min, the strength of the agglomerated clinker does not change, but decreases the productivity of the cooling process. Further cooling of the clinker from 200-400 ° C to 20-25 ° C is carried out at an average speed of up to 100 deg / min. The clinker, molded and cooled to 200-400 ° C in a given cooling mode (4-15 degrees / min), represents strong pieces, and the subsequent increase in the cooling rate to 100 degrees / min has almost no effect on their strength. When the cooling rate is higher than 100 ° C / min, the yield of fine fractions increases. Therefore, in order to intensify the cooling process of the molded clinker, the cooling is carried out in two modes. A type of clinker coming out of waelz furnaces with a temperature of 1050-1150 ° C or heated to such an interval of temperatures filled the molds of square section (llOx x OO mm) with a height of 200-500 mm or dimensions 30.0x500x200 mm to form it. in these molds and cooling. In order to obtain the required cooling rate, the mold was watered with water at different flow rates. To obtain high cooling rates (examples 14, 15), the molded clinker was periodically entirely immersed in a mold in water. High speeds in the second stage were not reached by immersing in water cooled to pieces of molded clinker of various sizes.

Clinker ingots, cooled to, were subjected to standard strength tests by dropping three times from a height.

2 m on a concrete base and determine the output of the fine fraction (minus 10 mm) after dropping. According to the technical conditions, the clinker entering the smelting of coal must have a co5 fraction (class minus 10 VS4) of no more than 10%.

The test results are given in the Q table.

As a result of attributions (see table), you can see that

The clinker before the beginning (W molding it into ingots should have a temperature of 1050-1150 C (experience 1-5).

A reduction in the yield of the fraction minus 10 mm is achieved when the clinker is cooled at a rate of not more than 15 degrees / min in the first stage of cooling (experiments 13-20).

The temperature of the clinker after the first stage of cooling should not be higher (experiments 6-13). The yield of the fraction is minus 10 mm after testing the molded clinker, depending on the mode of its cooling in two stages.

In order to intensify the cooling of clinker ingots from 200-400s to ambient temperature, it is possible to conduct without loss of strength at a higher speed than in the first stage, but not more than 100 degrees / mi (experiments 21-27) o

Reducing the cooling rate at the first and second clinker cooling below 4 deg / min does not lead to a significant increase in the strength of the clinker and a decrease in the yield of the fines (experiments 20, 27), but decreases the productivity of the preparation process.

Thus, in comparison with the prototype, the proposed method provides the following advantages; lower, the temperature of clinker heating from 1250-1300s to 1050-1150 ° C is eliminated and VEZ maintenance is excluded at elevated temperatures, which reduces fuel consumption and preparation; ensures that agglomerated clinker produces a grade of minus 10 mm does not exceed 10%.

The expected economic effect of RUB. per ton of recyclable clinker.

Claims (1)

METHOD FOR PREPARING A ZINC PRODUCTION CLINKER FOR Smelting, including its heating and cooling, characterized in that, in order to reduce fuel preparation costs, the clinker is heated to 1050-1150 ° C, molded and cooled to 200-400 ° C at a speed of '4- 15 deg / min, and then at a speed of up to 100 deg / min.