Selenium recovery from aqueous streams based on anaerobic technology using sludge from full-scale UASB digester
Removal of the toxic selenium anions selenate and selenite from wastewater before discharge is getting increasingly imperative in industrialized countries.Bacteria can reduce selenate to selenite,and also further to elemental selenium,selenide or organic selenium.In this study,we studied recovery of selenium from selenate or selenite simulated waste streams (~158 ppm Se) based on anaerobic batch technology at pH levels 6 to 8.Batches were inoculated with anaerobic granular sludges,designated Eerbeek and Emmtec,which were both cultivated in full-scale UASB reactors on organics and sulfate.Furthermore,we investigated removal of selenite down to ppb Se levels by chemical precipitation,adsorption on selenium sulfide (SeS2) and bioreduction in the presence of SeS2 or sulfur.The results indicate that the conversion of selenate to more reduced selenium (selenite or selenium) could reach 60% in 20 days with Eerbeek.Selenite removal could reach 95% with Eerbeek.Within the same time span,selenite removal efficiency could exceed 99% with sulfur and SeS2 addition for both sludges and the lowest level could reach 260 ppb Se,which was better than chemical precipitation and adsorption.
Selenium recovery,selenium sulfide anaerobic,bioreduction,wastewater treatment
Zhimou Wei Jan Weijma C.J.N.Buisman Kaijun Wang R.D.van der Weijden
School of Environment, Tsinghua University, Beijing 100084, PR China Sub-department of Environment Technology, Wageningen University, 6700 EV Wageningen, The Netherlands
国际会议
The 15th IWA World Conference on Anaerobic Digestion( 第15届IWA世界厌氧大会)
北京
英文
515-518
2017-10-17（万方平台首次上网日期，不代表论文的发表时间）