加热炉烟气反吹系统对蓄热体的影响

蓄热式加热炉在煤气换向阀切换为抽烟气时，烧嘴内的残余煤气与高温烟气发生二次燃烧，导致烧嘴局部温度瞬间高于蓄热体的最高使用温度，在高温和氧化铁粉末的共同作用下会造成煤气烧嘴第1层蓄热体出现开裂、变形、气孔堵塞的现象。研究了在加热炉上增设一套烟气反吹系统以解决蓄热体局部过烧的问题。实际应用效果表明，该系统以低温烟气将煤气烧嘴及支管内的残余煤气置换到炉内进行燃烧，不仅能杜绝煤气在烧嘴内发生二次燃烧，有效地控制蓄热体温度，延长其使用寿命，还能大幅度降低烟气中CO的含量，减少化学能耗损失和环境污染。

Effects on regenerator of the flue gas injecting system of reheating furnace

When the gas valves of the regenerative furnace is switched to pump the flue gas, the temperature of the burner＇s top bricks becomes higher than its allowed temperature in a moment due to the secondary combustion in the burner. Both the high temperature and the iron oxide powder above the bricks will cause the regenerator of the gas burner cracked and deformed andchannels clogged. To resolve this problem, the measure of injecting the flue gas in- to the gas pipelines was studied. The practical application shows that the system makes the residual gas of the gas burner and the branch replaced into the furnace for burning with low temperature flue gas. This system can effec- tively control the temperature of the regenerator and extend the regenerator＇s service life by preventing happening of secondary combustion in the burner, and greatly decrease the CO content in the flue gas and reduce chemical energy loss and environmental pollution.