Process for improving combustion efficiency of cement kiln by utilizing high-oxygen content air

Abstract

The invention provides a process for improving combustion efficiency of a cement kiln by utilizing high-oxygen content air. The process comprises the following steps: manufacturing high-oxygen content air with an oxygen content of 28% through a membrane method oxygen enrichment technology, and feeding 10-15% of the high-oxygen content air into a coal injection duct at the head part of the kiln through a blast pipe to combust pulverized coal in the kiln; sending 20-25% of the high-oxygen content air into delivery air of a coal injection duct at the tail part of the kiln through a blast pipe to combust pulverized coal in a decomposition furnace; sending 60-70% of the high-oxygen content air to an air outlet of a cooling fan at a high-temperature section of a grate cooler through a blast pipe, so that the high-oxygen content air and the cooling water are together sent into the grate cooler, and through heat exchange, the generated high-temperature secondary air with relatively high oxygen content is supplied to combust pulverized coal at the head part of the kiln. The process provided by the invention has the advantages of rapidly improving the temperature of the cement kiln, reducing the ignition temperature of the pulverized coal, improving the combustion speed of the pulverized coal, promoting the pulverized coal to be sufficiently combusted, improving the burn-off rate of the pulverized coal, reducing the smoke exhaust rate and saving the fuel. According to the process, the pulverized coal combustion environment of the kiln is improved, the cement quality is improved, and favorable economic benefit and social environment-friendly benefit are provided.

Description

Technical field: [0001] The invention relates to a technique for improving the combustion efficiency of a cement kiln by using air with high oxygen content, and belongs to the technical field of cement production. Background technique: [0002] At present, the thermal efficiency of various industrial boilers and kilns used in China is generally 60-80%, which means that the task of energy saving and emission reduction of industrial kilns still has a long way to go. With the urgent requirements of local governments for energy saving and emission reduction and the remarkable economic benefits of membrane method oxygen enrichment energy saving transformation projects, more and more enterprises will gradually realize the unique economic benefits of membrane method oxygen enrichment energy saving transformation. benefits and social benefits. Oxygen-enriched air participates in the combustion to provide enough oxygen for the combustion, so that the combustibles can be fully burned...

AI Technical Summary

Problems solved by technology

However, in the cement industry kilns, the unit fuel consumption is less than that of thermal power enterprises, and the combustion conditions are extremely demanding. At present, no cement enterprise has completely successfully applied this theoretical achievement.