从废液和废渣中回收硫并获得效益

介绍从硫酸和磺化剂装置产生的含硫废渣以及从磷酸装置产生的含硫酸盐废液中心收硫的几种技术。硫过滤机的滤饼和熔硫沉降懵的硫渣与65％发烟硫酸或液体SO3一起送入反应器生成SO2，SO2作为产品或送入硫酸厂生产硫酸，惰性物料干燥后填埋处理。采用生物技术利用硫酸盐还原菌将磷石膏中的硫酸盐还原成H2S气体，然后再通过Claus硫回收装置转化为硫磺。从含硫废渣中回收硫的方案不仅是环境友好的技术，而且可生成高附加值的纯净二氧化硫，而对于含硫碳氯化合物或矿物资源匮乏的国家来说，使用生物技术是一种可行方案，该工艺不仅可以解决排放问题，而且可以获得经济效益，然而要实现工业应用还需进一步努力。

Recovery of sulphur from liquid and solid waste with profit

Several technologies for sulphur recovery from solid waste containing sulphur generated during sulphuric acid production and sulphonation and liqiud waste containing sulphates generated in phosphoric acid manufacture are described. The solid cake from sulphur filters or sulphur sludge from settler section of sulphur melter are fed to reactor along with 65% oleum or liquid SO3 to form SO2 , which can be as a stand-alone product or sent to the acid plant for conversion to sulphuic acid and the resulting inert cake is then dried and sent for disposal to dump sites or for land filling. Biotechnology using sulphate-reducing bacteria can be used for reducing sulphate of phosphogypsum to H2S, which then is fed to a catalytic stage of Cluse SRU to convert to water and sulphur. The option for sulphur recovery from solid waste containing sulphur is not only an environment-friendly technique, but also would generate value-added pure sulphur dioxide. Biotechnology is a possible option for the countries which are not lucky enough to have hydrocarbon or ore deposits containing sulphur. It may not only tackle the effluent problem, but may also give an economic benefit. However, further effort is necessary to make the technique commercially acceptable to the industry.