水套加热炉烟气系统腐蚀的原因和预防

以卧89井水套加热炉的烟气系统为对象,调查了烟气系统的腐蚀情况,分析了烟道被堵塞导致回火的原因,从理论上推导分析了天然气在炉膛内的燃烧过程,烟气(燃烧余气)在烟气系统中的排放过程,并结合设备维修和技术改进的现场经验,确定烟气系统的腐蚀原因为氧腐蚀和二氧化碳腐蚀,纠正了四川天然气田生产中设计水套加热炉只考虑硫化氢腐蚀,忽略烟气中二氧化碳腐蚀的论点。解决方法是提高烟气的排放温度以减少冷凝水量,采用抗二氧化碳腐蚀的钢材和技术。

Causes for Corrosion of the Smoke-discharge System of the Water Jacket Heating Boiler and the Preventatives against Corrosion

In light of the smoke-discharge system of the Water Jacket Heating Boiler of Well Wo 89,the corrosion condition of the smoke-discharge system was investigated,the returning smoke resulting from the blocking of the flue was analyzed,and the natural-gas burning process in the boiler's chamber and the discharging process of the exhaust fumes were deduced.With the experience of equipment maintenance and technical improvement,the paper reached a conclusion that the cause for the corrosion of the smoke system was the oxygen and carbon dioxide corrosion.The paper also rectified the viewpoint that only hydrogen sulfide corrosion should be emphasized without consideration of carbon dioxide corrosion during the process of designing the water jacket heating boiler in the Sichuan Oil and Gas Field.The results show that the condensate can be decreased by increasing the temperature when the smoke is discharged,and the manufacturing craft can be improved by adopting the technique and steel materials against carbon dioxide corrosion.