摘要
某280kt/a苯乙烯装置蒸汽过热炉,随着运行周期增长,装置负荷提升,排烟温度由125℃逐步上涨至160℃,热效率由92.5%下降至91.4%,烟气中氮氧化物也时有超标现象。为解决上述问题,组织专题研究、论证,实施了一套科学的技术改造方案,技术改造主要内容包括在汽提塔之前增加凝液热交换器、加热炉对流段新增翅片管、采用低氮燃烧器,技术应用达到了预期效果,加热炉排烟温度降低至105℃左右,热效率提高至93.5%,烟气中氮氧化物含量降至65mg/m^(3)以下,大大低于国家排放标准。
The steam superheater of a 280kt/a styrene unit has increased the load of the unit with the increase of the operation cycle.The exhaust gas temperature has gradually increased from 125 ℃ to 160 ℃, the thermal efficiency has decreased from 92.5% to 91.4%, and the nitrogen oxides in the flue gas have also exceeded the standard from time to time. In order to solve the above problems, special research and demonstration were organized, and a set of scientific technical transformation scheme was implemented. The main contents of the technical transformation include adding a condensate heat exchanger before the stripper, adding finned tubes in the convection section of the heating furnace, and using low nitrogen burners. The technical application has achieved the expected effect. The exhaust gas temperature of the heating furnace is reduced to about 105 ℃, the thermal efficiency is increased to 93.5%, and the nitrogen oxide content in the flue gas is reduced to below 65mg/m^(3), Which is much lower than the national emission standard.
关键词
苯乙烯
过热炉
节能减排
styrene
superheater
conserve energy
reduce emissions