Method for roasting active lime with mixed gas in sleeve lime kiln

Abstract

A method for calcining active lime by the use of mixed gas in a lime sleeve kiln comprises the following steps: different consumption amounts of gas is respectively introduced into upper and lower combustion chambers of a combustion system of the lime sleeve kiln; blast-furnace gas is blown into the upper combustion chamber to keep oxygen free combustion and make combusted gas reach the temperature range of 1000-1100 DEG C required by limestone decomposition; and coke oven gas is blown into lower nozzles of the lower combustion chamber, the lower nozzles are multi-row structural layered combustors, a part of fuel in the layered combustors undergoes premixed combustion at a normal air-fuel ratio, high temperature generated by combustion makes an area where the air nearby is relatively thin satisfy ignition conditions and thereby ignition is carried out layer by layer, the combustion status of flameless oxidation is formed by combining recirculation flow of flue gas, and temperature is controlled within the range of 1150-1200 DEG C. According to the method, there is no need to build a gas mixing and pressuring station, and the purposes of accurately controlling lime calcination temperature, guaranteeing heat balance and reducing production costs of lime can be achieved.

Description

technical field [0001] The invention relates to a sleeve lime kiln, which belongs to the technical field of lime calcination, in particular to a method for roasting active lime using mixed gas in a sleeve lime kiln. Background technique [0002] At present, the domestic sleeve lime kiln has been widely used in the metallurgy and chemical industry, which has brought great economic effects due to its advantages of high efficiency, energy saving and environmental protection. The calcination process of the sleeve lime kiln uses combustible gas as fuel and high temperature calcination Lime production. Exhaust gas preheating is used to drive the wind, and the high-temperature and high-pressure driving wind sprays to trigger the circulating air circulation to realize the recycling of heat and reduce the heat consumption of lime production, so as to achieve the purpose of energy saving and consumption reduction. [0003] Coke oven gas or blast furnace gas or coke oven gas and conve...

AI Technical Summary

Problems solved by technology

In this way, there is a contradiction with the fact that the gas is mixed first and then enters the upper and lower combustion chambers for combustion.