低浓度烟气非稳态转化制酸工艺的应用

Application of unsteady state conversion process to sulphuric acid production with low-SO_2 off-gas

介绍了我国有色冶炼低浓度烟气现状、非稳态转化工艺及其特点,重点论述了转化器、换向阀、催化剂、DCS控制系统和尾气处理系统,并分析了几套非稳态转化制酸装置的运行情况。非稳态转化制酸工艺加尾气处理能够解决有色冶炼企业低浓度烟气[(?)(SO2)0．9％-4．0％]污染问题,产品硫酸w(H2SO4)92．5％左右,尾气经石灰中和处理后均能达标排放;但催化剂粉化较严重、转化率偏低(不能稳定在93％以上)、换向阀轴套和填料盖易磨损、产品硫酸呈浅黑色等问题亟待解决。

The present situation of China＇s low-SO2 non-ferrous metallurgical off-gas and the features of unsteady state conversion process are described with emphasis on converter, switching valve, catalyst, DCS system and tail gas treatment system. Operation situation of some sulphuric acid plants using unsteady state conversion technology are analyzed. Unsteady state conversion plus tail gas treatment system can solve the pollution problem about low-SO2 metallurgical off-gas[ φ（ SO2）0. 9% -4. 0% ] by producing w（ H2SO4）92. 5% sulphuric acid with tail gas up to the national emission standard. But some problems need to be solved, such as serious crush of catalyst, low and unstable conversion efficiency （lower than 93% ）, easily abraded shaft sleeve and packing gland and lightly blackened product sulphuric acid.