烟气中含氧量对氨法烟气脱硫系统氧化效果的影响

Effect of Oxygen on Flue Gas Ammonia Desulfurization System

襄阳泽东化工集团有限公司采用了以液氨作为脱硫剂的氨法锅炉烟气脱硫工艺,通过调节罗茨风机停运时间,考察烟气中含氧量对硫酸铵循环槽中硫酸铵、亚硫酸铵含量的影响。结合计算产品氧化理论需氧量,发现烟气中本身含氧量对亚硫酸铵具有氧化效果,该脱硫系统存在配风过量的问题。对此提出了增加风机变频调节或根据尾气氧含量间歇启运风机的措施,在保证对硫酸亚铵氧化的同时,优化工艺操作。

The flue gas desulphurization process with ammonia as absorbent was adopted in Xiangyang Zedong Chemical Group Co. LTD. The present work investigated effects of oxygen in flue gas on the amount ofammonium sulfate and ammonium sulfite in ammonium sulfate circulating tank by adjusting the runtime of Rootsblower. Combined with the theoretical oxygen demand,it was found that oxygen in flue gas could oxidizeammonium sulfite,and excessive air was supplied in the flue gas desulfurization system. Therefore,weproposed to add variable frequency regulation to the fan,or intermittently run the fan according to the oxygen content of the flue gas,which could optimize the process with guaranteeing the oxidation of ammonium sulfite.