预览加载中，请您耐心等待几秒...

高浓度含氯农药废水中化学耗氧量(COD_cr)测定方法的改进.docx

预览
1/2
2/2

在线预览结束，喜欢就下载吧，查找使用更方便

下载提示 文本预览

如果您无法下载资料，请参考说明：

1、部分资料下载需要金币，请确保您的账户上有足够的金币

2、已购买过的文档，再次下载不重复扣费

3、资料包下载后请先用软件解压，在使用对应软件打开

高浓度含氯农药废水中化学耗氧量(COD_cr)测定方法的改进 高浓度含氯农药废水中化学耗氧量(COD_cr)测定方法的改进 Abstract:Asoneoftheimportantparametersreflectingthedegreeoforganicpollutioninwater,ChemicalOxygenDemand(COD)hasbeenwidelyusedinwaterqualitymonitoring.However,theconventionalmethodofCODmeasurementbasedondichromateoxidationisnotapplicabletohigh-concentrationchlorinatedpesticidewastewaterduetothesignificantinterferenceofchlorideions.Inthisstudy,animprovedCODmeasurementmethodwasdevelopedforhigh-concentrationchlorinatedpesticidewastewater.Themethodinvolvesreducingtheinterferenceofchlorideionsbyaddingsilversulfate,andoptimizingthedigestiontemperatureandtime.TheresultsshowthatthisimprovedCODmeasurementmethodisaccurate,precise,andreproducibleforhigh-concentrationchlorinatedpesticidewastewater. Introduction: AgriculturalproductionisoneofthemainsourcesofwaterpollutioninChina.Inparticular,theexcessiveuseofchlorinatedpesticideshascausedseriousenvironmentalpollutionandhealthproblems.Chlorinatedpesticidewastewatercontainshighlevelsoforganiccompoundsandchlorideions,whichposeasignificantchallengefortheaccuratemeasurementofChemicalOxygenDemand(COD).TheconventionalCODmeasurementmethodbasedondichromateoxidationcannotbeappliedtochlorinatedpesticidewastewaterduetotheinterferenceofchlorideions.Therefore,improvingtheCODmeasurementmethodforhigh-concentrationchlorinatedpesticidewastewaterisurgentlyneeded. MaterialsandMethods: Thechlorinatedpesticidewastewatersamplewascollectedfromalocalpesticideplant,whichcontainsvarioustypesofhigh-concentrationchlorinatedpesticidesandahighconcentrationofchlorideions.Thesamplewaspretreatedbyremovingsuspendedsolidsandfilteredwitha0.45μmmicroporousmembrane.TheCODwasmeasuredusingtheconventionaldichromateoxidationmethodwiththeadditionofsilversulfatetoreducechlorideioninterference.ThedigestiontemperatureandtimewereoptimizedtoimprovetheaccuracyandprecisionoftheCODmeasurements.TheCODvaluesobtainedbytheimprovedmethodwerecomparedwiththoseobtainedbytheconventionalmethodtoevaluatetheperformanceoftheimproved