高焦混合煤气管道腐蚀堵塞原因分析

Cause Analysis of Corrosion and Blockage of High Coke Mixed Gas Pipeline

以武钢二冷轧厂高焦炉煤气管道为例,针对高焦炉煤气管道腐蚀堵塞问题,通过对管道内腐蚀介质与腐蚀产物进行分析,探讨了煤气管道腐蚀堵塞的原因与机理。结果表明:管道内腐蚀产物主要由氧化铁与单质硫组成,煤气及其冷凝水中也含有大量HS等腐蚀介质,因此造成高焦炉管道腐蚀的主要是由HS引起的,HS溶于冷凝水后,在管道内表面形成一层腐蚀液膜,使其发生电化学腐蚀,随着管道温度较低,形成的腐蚀产物沿管道堆积,造成煤气管道的堵塞。

Taking high coke oven gas pipeline of the second cold rolling plant of Wuhan steel as an example,cold aiming at the problem of corrosion and blockage of high coke oven gas pipeline,the causes and mechanism of corrosion and blockage of gas pipeline are discussed by analyzing the corrosion medium and corrosion products in the pipeline.The results show that the corrosion products in the pipeline are mainly composed of iron oxide and elemental sulfur,and the gas and its condensate also contain a large amount of HS and other corrosive media.Therefore,the main cause of high coke oven pipeline corrosion is caused by HS.After HS dissolves in the condensate,a layer of corrosive liquid film is formed on the inner surface of the pipeline,causing electrochemical corrosion.With the low temperature of the pipeline,the corrosion products formed accumulate along the pipeline,causing the blockage of the gas pipeline.