【摘要】 针对NH3N浓度为200—1000mg·l-1的废水,以磷酸铵镁沉淀法去除NH3N,通过正交试验确定影响磷酸铵镁沉淀反应的因素依次为:pH值,PO3-4∶NH+4,Mg2+∶NH+4和反应时间;最优反应条件分别为pH=8,Mg2+∶PO3-4∶NH+4=1.4∶1.2∶1,反应时间10min,分别考察pH值,PO34投加量,Mg2+投加量和NH3N初始浓度对磷酸铵镁沉淀法去除NH3N的效率及出水NH3N和TP浓度的影响,对养猪场废水和焦化废水中NH3N的处理,最高去除率分别达到81.01%和73.63%,同时,两种废水相应的COD和色度的最大去除率分别达到81.33%、72.97%和50.27%、20.94%.更多还原

【Abstract】 Propose apretreatment method of magnesium ammonium phosphate(MAP)precipitation for wastewater which contains 200 to1000mg·l -1 ammonia-nitrogen. Principalordersof factors, which affect MAP precipitation process, concluded by orthogonalexperiment are as following:pH value, PO 3-_ 4∶NH+_ 4, Mg 2+∶NH+_ 4and residence time. The optimum reaction conditionsare pH 8.0,Mg 2+∶PO 3-_ 4∶NH+_ 4= 1.4∶1.2∶1 and t=10min. The effects of pH, phosphate amount, magnesium ion amount and initial ammonia-nitrogen concentration on ammonia-nitrogen removal efficiency and the residual concentrations of ammonia- nitrogen and total phosphorus havebeen investigated respectively. Ammonia-nitrogen removing tests of swine farm wastewater and coking wastewater MAP precipitation were performedunder theoptimum conditions, and the best removal efficiency were 81.01% and 73.63%. At the same time, 81.33%and 72.97% removal rate for COD_ Cr, together with50.27% and 20.94% removal rate for chromaticity color wereachieved about swine farm wastewater and coking wastewaterrespectively. The results indicate that MAP precipitation for ammonia-nitrogen removal hasa practice value.更多还原