尿素、铵根离子溶液/添加剂的湿法脱硝

Removal of NOx by Solutions of Urea and Ammonium Ion/Additives

对NOx在液相吸收过程中的传质过程进行分析;采用尿素和铵根离子组合成的3种不同吸收剂,在填有金属鲍尔环的串联喷淋吸收塔反应器中,对模拟烟气进行湿法脱硝研究;实验分别对气速、液气流量比、吸收剂质量分数、气体温度、吸收剂温度、添加剂质量分数、NOx体积分数和SO2是否存在等条件对脱硝效率的影响规律进行了研究.研究表明,铵根离子溶液的脱硝效率不如尿素溶液的脱硝效率高,并且气速、液气流量比、系统温度、添加剂质量分数和NOx体积分数均对脱硝效率有重要影响;加入2,000×10-6 SO2后,其脱硝效率可提高5%,说明SO2与NOx在同一系统中具有协调促效作用.

Mass transfer of NOx in the liquid phase was analysed. Using three different absorbents made of urea and ammonium, wet denitrifieation was investigated in sprinkling absorption reactors filled with steel pall rings. A series of experiments were carried out to study operation parameters, such as gas velocity, ratio of liquid to gas, absorbent concentration, gas temperature, absorbent temperature, additive concentration, NOx concentration and SO2 existence. The experimental results indicated that urea solution was more efficient in NOx removal than ammonium ion solution. At the same time, gas velocity, ratio of liquid and gas, system temperature, additive concentration and NOx concentration had great effects on the removal efficiency of NOx from flue gas. When 2 000 ×10^-6 SO2 was added, the efficiency of denitrification was improved by 5%, which showed that there existed a mutual promotion effect of SO2 and NOx in the same system.