Method for stepwise cooling cement clinker

Abstract

The invention provides a method for stepwise cooling a cement clinker. The method is characterized by comprising steps of (1) first-stage quick cooling; (2) clinker crushing; and (3) second-stage conventional cooling. The cooling method comprises first-stage cooling and second-stage cooling, and the cooling volume of the two cooling stages can be controlled independently, so that the stability of the system is improved, and air mixing among air openings can be avoided; air entering a first-stage cooler is subjected to heat exchange to form high-temperature hot air which is completely used for supplying secondary and tertiary air for a system, wherein the average temperature after the secondary air and the tertiary air are mixed can be more than 1050 DEG C, so that the heat recovery efficiency of the cooler can be over 85 percent; a crushing step is executed before second-stage cooling, so that the contact area of the clinker and cooling air in a second-stage cooler can be increased, the air entering the second-stage cooler is only 0.6-0.8Nm<3> / kg.cl, and the air volume is remarkably reduced; furthermore, the temperature of formed hot air is remarkably increased, so that caloric content in the clinker is recycled as much as possible; and the total cooling air volume in the two cooling stages can be controlled under 1.5Nm<3> / kg.cl, and the total air volume is remarkably reduced.

Description

technical field [0001] The invention belongs to the field of cement industry manufacturing, and in particular relates to a method for distributed cooling of cement clinker used in a dry-process cement clinker burning system. Background technique [0002] In the cement production process, especially in the dry process cement production process, after the cement clinker is fired, the clinker needs to be cooled. The existing clinker cooling method is as follows: the high-temperature clinker at 1300℃~1450℃ is discharged from the kiln mouth of the rotary kiln to the grate bed of the rapid cooling machine, and distributed along the entire length of the grate bed to form a material bed of a certain thickness. The cooling air is blown into the material layer from the bottom of the material bed, penetrates and diffuses, and cools the hot clinker. Usually, the total cooling air volume is 1.7-2.1Nm 3 / kg.cl. The cooling air after cooling the clinker becomes hot air, which forms hot a...

AI Technical Summary

Problems solved by technology

[0003] 1. In terms of the air used for clinker cooling, due to the fluctuations in different on-site production, it will cause cross air between the air intakes, resulting in low temperature of the secondary and tertiary air, which affects the stability of the process

[0004] 2. The heat recovery rate of the cooling machine can only reach about 74% (the heat recovery rate is represented by the ratio of the enthalpy of the second and third winds to the enthalpy of the clinker entering the cooler from the kiln), and the heat recovery rate is low and needs to be further improved

[0005] 3. The total air volume of the cooler is too high