摘要
采用分步化学沉淀法分别脱除并回收磷酸铁生产废水中的高浓度磷酸根和硫酸根。实验结果表明:在以n(Fe^(3+))∶n(PO_4^(3-))=1.0的比例加入硫酸铁、反应时间为40 min、反应温度为25℃、废水初始p H为8.17、反应30 min时二次调节废水p H至5.50的条件下,磷酸根去除率可达98%以上,所得沉淀中Fe和P的质量分数分别为36.77%和18.81%,成分简单,回收价值高;采用氢氧化钙作为沉淀剂,在n(Ca^(2+))∶n(SO_4^(2-))=1.0的条件下可将废水中硫酸根质量浓度由78.62 g/L降至2.16 g/L,硫酸根去除率为97.3%,硫酸钙回收量为120.2 g/L;最终出水的磷酸根质量浓度小于0.5 mg/L,满足GB 8978—1996《污水综合排放标准》的一级标准。
The high concentration PO43- and SO42- in ferric phosphate production wastewater were removed and recovered by stepwise chemical precipitation process. The experimental results showed that：Under the conditions of adding ferric sulfate with n（Fe3＋）∶n（PO43-）=1.0,reaction time 40 min,reaction temperature 25 ℃,initial wastewater pH 8.17 and second adjustment pH 5.50 at 30 min,the PO43- removal rate reached above 98%,and the mass fraction of Fe and P in the precipitate was 36.77% and 18.81% respectively,which indicated that the composition of the precipitate was simple and its recycling value was enormous;Under the conditions of using calcium hydroxide as the precipitant and n（Ca2＋）∶n（SO42-）=1.0,the mass concentration of SO42- in the wastewater was reduced from 78.62 g/L to 2.16 g/L,the SO42- removal rate was 97.3%,and the recovery of calcium sulfate was 120.2 g/L;The PO43- mass concentration of the final effluent was less than 0.5 mg/L,which met the first grade standard of GB 8978-1996.
作者
李雅
刘晨明
刘凤梅
安慧蛟
林晓
LI Ya;LIU Chenming;LIU Fengmei;AN Huijiao;LIN Xiao(Beijing Engineering Research Center of Process Pollution Control,Institute of Process Engineering,Chinese Academy of Sciences,Beijing 100190,China;Quzhou Hua You Cobalt New Material Co.Ltd.,Quzhou Zhejiang 324000,China)
出处
《化工环保》
CAS
CSCD
北大核心
2018年第4期413-418,共6页
Environmental Protection of Chemical Industry
基金
中华人民共和国工业和信息化部资助项目(锂离子电池材料全生命周期绿色制造)
关键词
磷酸铁
分步沉淀
磷酸根
硫酸根
回收
ferric phosphate
stepwise precipitation
phosphate radical
sulfate radical
recovery
