Method for producing cement clinker from coal gangue and metal tailing substituting clay ingredient

Abstract

The invention discloses a method for producing cement clinker through coal slack and metal tailings instead of clay. The method comprises the following steps: preparing and milling crude materials; and then calcining the crude materials in a dry-process rotary kiln to form the cement clinker. The crude materials comprise the following components in percentage by weight: 85 to 90 percent of limestone, 1 to 2 percent of iron material, 3 to 8 percent of coal slack, and 2 to 5 percent of metal tailings. The metal tailings can be copper tailings, lead zinc tailings or copper lead zinc tailings. The method adopts the coal slack and the metal tailings instead of clay as the crude materials, and activates the reaction activity of the coal slack through the geologic potential of the tailings, thereby having the actions of mutual advantageous complementation. The method has easily obtained and cheap raw materials, easily mastered raw materials preparation, simple process, and obvious energy conservation. The clinker yield is improved by above 10 percent than the designed yield; and the raw material cost is reduced relatively by above 5 percent.

Description

(1) Technical field [0001] The present invention relates to a method for producing cement clinker. (2) Background technology [0002] my country's physical output of cement has ranked first in the world for 22 consecutive years since 1985. In 2007, the total output of cement reached 1.35 billion tons. Most of the cement industry uses high-grade limestone resources and high-quality clay as raw materials. Clay is the main silica-alumina raw material for cement production, and about 0.18 tons of clay are needed for one ton of cement production. Large-scale clay extraction in successive years has caused a large number of fields to be destroyed, forests have been destroyed, and the ecology has been threatened. The development of clay as a substitute raw material has become an urgent task for the cement industry. [0003] The mineral components of coal gangue are mainly kaolin, quartz, montmorillonite, and Yili stone, and the chemical composition is SiO 2 、Al 2 o 3 It account...

AI Technical Summary

Problems solved by technology

[0005] However, although most coal gangue and metal tailings can replace clay to produce cement clinker, for some coal gangue, which is an inert raw material, the reaction ability is low, and the high activation energy of reaction is not conducive to clinker firing.

The melting point of some metal tailings is too low, it is easy to make rings and crusts in the kiln, making it difficult to calcine

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