硫黄制酸装置氨法脱硫系统近零排放改造

Near zero discharge transformation of ammonia desulfurization system in sulphur-burning sulphuric acid plant

介绍了威顿达州化工有限责任公司800 kt/a和400 kt/a硫黄制酸装置氨法脱硫系统的工艺改造情况和运行效果。在原脱硫系统的脱硫塔前增加管道吸收器,形成两级氨水吸收并使两级循环母液产生密度差,在原脱硫塔后新增1个集塔、槽、电除雾器于一体的组合塔,形成了“两级氨水脱硫吸收+一级水洗涤+两级电除雾”的脱硫系统。经过两次改造,逐步实现了外排废气的二氧化硫排放浓度为0,硫酸雾(ρ)<5 mg/m^(3),达到了低于特别排放限值的近零排放。

The process transformation and operation effect of ammonia desulfurization system in 800 kt/a and 400 kt/a sulphur based sulphuric acid plants of Wylton Dazhou Chemical Co.,Ltd.are introduced.The pipeline absorber is added in front of the desulfurization tower of the original desulfurization system to form two-stage ammonia absorption and cause the density difference of the two-stage circulating mother liquor.A combined tower integrating tower,tank and electric demister is added behind the original desulfurization tower to form a desulfurization system of“two-stage ammonia desulfurization absorption+primary water washing+two-stage electric demister”.After two transformations,the sulfur dioxide emission concentration of the discharged waste gas is 0,and the emission mass concentration of sulphuric acid mist is gradually less than 5 mg/m^(3),reaching near zero emission below the special emission limit.