以废磷酸为磷源的MAP法去除污泥压滤液中的氨氮

Removing NH_3-N from sludge pressure filtration liquid by MAP process with waste phosphoric acid as phosphorus source

利用废磷酸作为MAP法的磷源处理污泥压滤液厌氧出水中的NH_3-N,考察了反应时间、搅拌方式、pH值、氮磷镁物质的量之比、初始NH_3-N浓度对NH_3-N去除效果和残余PO_4^(3-)浓度的影响,并确定了最佳反应条件。试验结果表明,当原水NH_3-N的质量浓度为700.42 mg/L,PO_4^(3-)的质量浓度为0.33 mg/L时,常温下,最佳反应条件为p H值为9,n(NH_4^+)∶n(PO_4^(3-))∶n(Mg^(2+))=1∶1∶1,曝气搅拌反应10 min。此时,NH_3-N的去除率可达84.91%,出水NH_3-N的质量浓度为105.69 mg/L,残余PO_4^(3-)的质量浓度为6.49 mg/L。以废磷酸作为沉淀剂磷源的MAP法,具有较好的NH_3-N处理效果,可用于高浓度NH_3-N废水的预处理。

Using MAP process with waste phosphoric acid as phosphorus source to treat NHz-N in sludge pressure filtration liquid, the effect of reaction time, stirring mode, pH value, mass ratio of nitrogen, phosphorus and magnesium and initial NH3-N concentration on NH3-N removal and residual PO4^3- concentration were investigated, and then, the optimal reaction condition was determined. The results of the test showed that, when the mass concentrations of NH3-N and PO4^3- were 700.42 and 0.33 mg/L respectively, under normal temperature, the optimal reaction condition was： the pH value was 9, n（NHa＋） ： n（PO4^3-） ： n（Mg2＋） = 1 ： 1 ： 1, the aeration stirring time was 10 rain. Under the above condition, the removal rate of NH3-N reached 84.9%, the mass concentra- tions of NH3-N and residual PO4^3- in the effluent water were 105.59 and 6.49 mg/L respectively. It could draw a conclusion that, MAP process with waste phosphoric acid as phosphorus source had a good removing performance on NH3-N and could be used for pretreatment of high concentration NH3-N wastewater.