Combined white cement combustion bleaching system

Abstract

The invention relates to a combined white cement combustion bleaching system, which comprises a combustor (1), a high-temperature heat exchanger (4), a primary air pipe (5), a pre-dedusting device (6), a high-temperature fan (7), a grate cooler (8), a low-temperature heat exchanger (9) and a dust collector (10), wherein an ignition oil gun channel (1-18), a center air channel (1-17), a coal supply air channel (1-16), a rotational flow air channel (1-15), an axial flow air channel (1-14) and a cold water channel (1-12) are formed in the left end of the combustor (1) in the axial direction. According to the invention, hot steam can be prevented from flowing into the rotary kiln to reduce the temperature of flame in the kiln, so that free calcium in clinker is prevented from exceeding the standard so as to effectively guarantee the quality of the clinker; and the temperature difference between the primary air and the rotary kiln (2) is reduced, so that the flame temperature in the rotary kiln is further prevented from being reduced, and further the increase of firing heat consumption is effectively avoided so as to greatly reduce the production cost.

Description

technical field [0001] The invention relates to a combined white cement combustion bleaching system. Background technique [0002] White cement is widely used in architectural decoration projects because of its convenient use, easy color adjustment and low price; because it is easy to process and shape, it is also used to make decorative parts with artistic characteristics; whiteness is an evaluation of the quality of white cement Important indicator, due to the small amount of Fe present in the clinker under high temperature conditions 3+ There is a coloring ability, so Fe needs to be 3+ Reduced to Fe with weaker coloring ability 2+ At present, the white cement clinker is mainly bleached by spraying water to quench it. The principle is to use the H decomposed by water vapor under high temperature conditions. + Will Fe 3+ reduced to Fe 2+ , to generate FeO, OH with weak coloring ability + It has strong reducing property, and the reducing atmosphere can prevent Fe 3+ G...

AI Technical Summary

Problems solved by technology

[0003] There are two kinds of water spraying and quenching bleaching methods for white cement clinker: water spraying outside the kiln and water spraying inside the kiln. The whiteness of the clinker can generally reach 81% to 84% during bleaching by spraying water outside the kiln. Water is sprayed inside, so the rapid cooling process will not affect the amount of materials added to the kiln, and the moisture content of clinker can be controlled below 2%. However, it is difficult and costly to transform ordinary cement into white cement; The spraying device is installed in the cooling zone of the kiln head. The clinker cooled in the kiln can have a whiteness of more than 86% and a moisture content of less than 1%. In addition, it only needs to modify a part of the kiln head cover, and the cost is low.

[0004] However, due to the hot steam generated by water spraying and quenching in the kiln, it is easy to escape into the rotary kiln, thereby reducing the flame temperature in the kiln, causing the clinker free calcium to exceed the standard, and affecting the quality of the clinker; The heat consumption has been greatly increased, which will lead to an increase in production costs, and it is urgent to wait for a solution

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