Method for calcining novel dry-method cement clinker by brown coal

Abstract

The invention discloses a method for calcining novel dry-method cement clinker by brown coal, wherein the method comprises that the brown coal is sent to a decomposing furnace as a calcining fuel after crushed and homogenized. Based on characteristics of short combustion time of the decomposing furnace and long combustion time of a rotary kiln, the method of the invention uses brown coal to replace common novel dry-method soft coal as a fuel of the decomposing furnace, and the rotary kiln still uses soft coal or/and anthracite with characteristics of high heating value and long combustion time, wherein the brown coal has characteristics of low heating value, low price, fast flaming speed and short combustion time, and the soft coal has characteristics of high price and long combustion time. The method enables fuel characteristics to accord with different combustion characteristic requirements of the decomposing furnace and the rotary kiln, is in favor of raising a burn-off rate of coal dust and raising a decomposition speed of calcium carbonate, reducing buildups jam of a preheater system, enables a utilization rate of brown coal for producing novel dry-method cement to reach more than 60%, fully utilizes a local coal resource, raises an energy utilization rate, and further reduce a production cost of cement.

Description

technical field [0001] The invention belongs to the technical field of cement production, and relates to a method for calcining new dry-process cement clinker by using lignite, in particular to a method for calcining new dry-process cement clinker by using lignite. Background technique [0002] The new dry process cement process refers to the production method of cement produced by the pre-decomposition technology outside the kiln, and its production is based on the suspension preheater and the decomposition technology outside the kiln. The emergence of pre-decomposition technology is a technological leap in the cement calcination process. It is to add a decomposition furnace between the preheater and the rotary kiln, use the ascending flue at the kiln tail, and install a fuel injection device to make the exothermic process of fuel combustion and production The endothermic process of carbonate decomposition of raw materials is carried out rapidly in the calciner in a suspend...

AI Technical Summary

Problems solved by technology

However, the regional distribution of my country's coal reserves is very uneven. A large number of new dry-process coals are concentrated in parts of North China, Northwest China and Central South China. For example, Yunnan lignite accounts for 75% of the proven coal reserves, and Guangdong lignite accounts for 45%. Bituminous coal is used in all of them. It is not conducive to the comprehensive and effective utilization of lignite, and it is the main reason for the high production cost of local cement enterprises

At present, lignite is rarely used alone or in a large proportion in the production of new-type dry cement as the fuel for the calciner. For example, the Chinese invention patent CN101759382A uses lignite to burn through the burner, and the flame after combustion enters the calciner and the rotary kiln respectively. There are complex processes, Disadvantages of difficult control of calcination quality

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