Method and system for online predication of flue gas temperature of calcination section in rotary kiln

Abstract

The invention relates to a method and a system for online predication of flue gas temperature of a calcination section in a rotary kiln. The method comprises the following steps in specific: S1, constructing a heat balance model about Q secondary air, Q fuel, Q flue gas, Q wall and Q material in the rotary kiln; S2, working out the numerical values of Q wall, Q material and Q secondary air in theheat balance model through the parameters when the rotary kiln works stably; S3, substituting the obtained numerical values of Q wall, Q material and Q secondary air into the heat balance model of therotary kiln in S1 to obtain the relational expression of Q fuel and Q flue gas to further obtain the relational expression of the calcination section fuel gas temperature tr and the kiln tail flue gas temperature ty; S4, measuring the kiln tail flue gas temperature ty, and obtaining the calcination section fuel gas temperature tr through the relational expression of the calcination section fuel gas temperature tr and the kiln tail flue gas temperature ty; and S5, the heat balance model is specifically as follows: Q secondary air+Q fuel=Q flue gas+Q wall+Q material. The method has the benefitof effectively predicating the temperature of the calcination section of the rotary kiln to provide theoretical support for production of the rotary kiln.

Description

technical field [0001] The invention relates to the technical field of rotary kilns, in particular to a method and system for online prediction of flue gas temperature in a calcining section in a rotary kiln. Background technique [0002] Rotary kiln is a key equipment widely used in cement, metallurgy and other production links. The control of its internal temperature is directly related to the stable operation of the entire production line, product quality and production cost. The heat released by fuel combustion will produce a high temperature zone. For a pellet rotary kiln under stable operation, it is generally around 1350 degrees Celsius. This temperature is an extremely critical process parameter in production and is directly related to fuel consumption and pellet quality. , nitrogen oxide emissions and cylinder ring formation. However, the high-temperature flue gas temperature in the calcining section of the rotary kiln cannot be directly measured for three reasons:...

AI Technical Summary

Problems solved by technology

[0004] 2) The rotary kiln is working in a rotating state, and the calcining section is located in the kiln, so it is difficult for measuring tools to reach in;

[0005] 3) The fluid in the rotary kiln is in a state of rapid flow, generally around 20m / s, and even exceeds 50m / s at the nozzle, making measurement difficult

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