络合沉淀结合混凝法去除浮选废水中有机磷

广西某铅锌矿选矿厂用含磷有机浮选药剂苯胺黑药(学名:二苯胺基二硫代磷酸)和丁铵黑药(学名:二丁基二硫代磷酸铵)作捕收剂,导致尾矿库溢流口外排废水总磷超标(总磷浓度为1.4~1.7 mg/L,pH=8.0)。实验研究表明,含巯基磷酸盐浮选废水中总磷主要为有机磷(占94%),钙盐、铁盐和铝盐混凝沉淀法对有机磷去除效果很差,3种金属离子不能与巯基磷酸盐反应生成沉淀物;但铜离子能与巯基磷酸盐生成溶度积很小的络合沉淀物,再通过混凝沉淀对有机磷可达到很好的去除效果。先加入硫酸铜20 mg/L进行络合沉淀反应,后再加入40 mg/L硫酸铝和1 mg/L PAM混凝沉淀,总磷去除率可达80%。处理后废水总磷浓度和重金属浓度均达到《铅、锌工业污染物排放标准(GB25466-2010)》排放要求。研究结果为该选矿厂浮选废水净化处理和回用工程的设计提供了科学依据。

Dephosphorization of flotation wastewater containing organophosphor using complex precipitation method

A Lead-zinc concentrator in Guangxi Province has been using aniline dithiophosphate and butylamine dithiophosphate as collectors. Total phosphorus (TP) of discharge wastewater from the tailing is 1.4~1.7 mg/L and over the discharge standards. The experimental results show that 94% of total phosphorus is organic phosphorus in the flotation wastewater. The organic phosphorus of wastewater could not be removed through the coagulation sedimentation using calcium salt, ferric salt and aluminum salt. But the addition of copper surfate could effectively remove the organic phosphorus because the reaction of copper ion and mercapto-phosphate resulted in the formation of stable complex sediment. The removal rate of TP can come up to 80% under the optimum conditions: the dosages of 20 mg/L CuSO4, 40 mg/L Al2(SO4)3 and 1 mg/L PAM. After the discharge wastewater from the tailing was treated through the complex precipitation, the concentration of total phosphorus and heavy metals were lower than the national industry discharge standard.The results provide a scientific basis for the flotation wastewater purification and recycling projects.