电化学沉淀法从废水中回收鸟粪石陈龙

812Vol．8No．12201412ChineseJournalofEnvironmentalEngineeringDec．2014*710064CO2pH。pHⅠ、Ⅱ2。ⅠⅡ。123V3．6V34Ca2+Ca2+5。X52A1673-9108201412-5264-07ＲecyclingstruvitefromwastewaterwithelectrochemicalprecipitationChenLongZhaoJianqiangZhangYuWangJieqiongSchoolofEnvironmentalScienceandEngineeringChang’anUniversityXi’an710064ChinaAbstractAlthoughnitrogenandphosphorouscanberemovedbymeansofstruvitewhichcanbeformedbyaddingchemicalsorstrippingcarbonoxideinthewastewaterfewstudiesfocusedonusingelectrochemicalprecipitationmethodtorecoverstruvite．InordertoexplorethefeasibilityofrecyclingstruvitebyelectrochemicalprecipitationtwoseriesexperimentsseriesⅠandseriesⅡwerecarriedoutfordeterminingtheoptimaloper-ationconditions．InexperimentspHvalueswereadjustedbythemethodofelectrolysis．InseriesⅠthecath-odewasstainlesssteelandtheanodewascarbonrod．InseriesⅡthecathodewasstainlesssteelandthean-odewasmagnesiumrod．Theresultsindicatedthat1thestruvitewasenrichedinthestainlesssteelnetsanditwasconvenientforcollecting．2Whenanodeswerethecarbonrodorthemagnesiumrodoptimalelectroly-sisvoltageswere3Vand3．6Vrespectively．3Nostirringorlow-velocitystirringwasbeneficialforthefor-mationofthestruvite．Temperaturedidnothavesignificanteffectsontheformationofthestruvite．4Lowcon-centrationCa2+hardlyaffectedthevelocityoftheelectrolysisreaction．HighconcentrationCa2+affectednotonlythereactionvelocitybutalsothethestruvitepurity．5Treatingthesludgedewateringfiltratebycarbonrodormagnesiumrodasanodesdidnothavesignificantdifferences．Highpuritystruvitecanbeobtainedandexpensecanbesavedunderbothconditions．Keywordselectrochemicalprecipitationwastewaterstruvitefactorsmagnesiumanode2013G32920172013－11－222013－12－191988—。[e-mail]*[e-mail]4PO4·6H2O、2、。。pH1。2。StratfulpH7．0Mg2+NH+4PO3－4187、266742mg/L1∶1．9∶1pH7．512pH8．5Mg2+92%3。pHpHpH4。pHpH8～105。pH、67NaOH、MgOH2、CaOH2CO22140～460/t97%40～508。。。。9。10。11．11Fig．1Experimentalapparatussketch1。1LΦ1cm×18cm24．5cm×12cm×0．02cmpHpH。78-1A。NH4H2PO4MgSO4·7H2ONH42SO4KH2PO4NaOH。1．2A2/O1。1Table1QualityofsludgedewateringfiltratepH7．6PO3－4mmol/L6．0℃28NH+4mmol/L24CODmg/L182Ca2+mmol/L3．2SSmg/L1067Mg2+mmol/L0．841．32ⅠII。1．3．1Ⅰ。4．5mmolNH4H2PO40．45L14．5mmolMgSO4·7H2O0．45L2。25L1N∶P∶Mg=1∶1∶1111mol/LNaOHpH7．015℃。24h。2．4、3、3．6、4．2、4．8、5．46V712。Ca2+。562581．3．2IIⅠ。Ⅰ7。1．4X。。∶40．00mgpH＜1250mL。11314=n×Mm×100%1nmolMg/molmg。22．12．1．1ⅠpH。。pHpH。2．4、33．6V310、2030mA3．2、6．49．5mA/cm2pH7．8～8．5、8．2～9．38．5～9．84．2、4．8、5．46V450、60、80100mA15．9、19．1、25．531．8mA/cm2pH9．0～10．2、9．6～10．8、10．4～11．711．2～13．5。2h2．4～3．6V2hPO3－480．45%～87．86%NH+480．89%～85．03%4．2～6VPO3－442．27%～63．36%NH+450．27%～54．41%。N、PpH10OH－Mg2+MgOH2Mg2+。3V3．6VN、P3V2h。2．1．20、60、120180r/min3．0V2h2。2Fig．2EffectsofrotationspeedsonremovalefficiencyofNandP2N、P。2。N、P。。2．1．35℃30℃156625123Fig．3EffectsoftemperaturesonremovalefficiencyofNandP3V35～25℃75%25℃。2．1．4Ca2+Ca2+25℃3VCa2+Ca2+N、P。4。4、Fig．4ＲemovalefficiencyofNandPandstruvitepurityvs．calciumconcentrations4PO3－4Ca2+NH+4PO3－4Ca2+、Mg2+Ca3PO42、Mg3PO42Ca5OHPO43。5。5Ca2+。5400Fig．5Micrographofsedimentsatdifferentcalciumconcentrationsmagnified400timesXＲD6。Ca2+、Jade5PDFCa2+1mmol/L16Ca2+5mmol/L762586XＲDFig．6XＲDpatternsofpurestruviteandtheharvestedprecipitatesCa2+10mmol/LCa3PO42、Mg3PO42。Ca2+Ca2+Ca2+。2．22．2．1。2．4～6V7Ⅰ。N、P。2．4、4．24．8V32h、5．4V6V0．5h3V、3．6V、N、P。2．4V41%47%N、P4．2～6V20%～43%N28%～62%P3V42%N65%P3．6V61%N80%P。pHpHpH11～13OH－PO3－4NH+4Mg2+MgOH23．6V。3．6VXＲD7PDF。2．2．2、、A、B21。2PO3－4100%ANH+442．37%B46．21%A90．31%B92．62%。。8625127XＲD3．6VMg400Fig．7XＲDpatternsandmicrographofharvestedprecipitates2．31tNH+4106．1mg/LPO3－437．2mg/L1．9kgNa2HPO4·12H2O98%2．2kgMgSO4·7H2O99%1．8kgNaOH17。Na2HPO4·12H2O、MgSO4·7H2ONaOH3900/t、700/t2800/t1t13．990．2/t1t14．19。2．2kgMgSO4·7H2O、1．9kgNa2HPO42kWh/tkWh0．51t10．21t10．15。1．9kgNa2HPO4211．22/t0．18/t1t10．79。1t4．043．4。313V3．6V。2Ca2+Ca2+。3。41t4．043．4。1．．201028547-50WangT．LuoJ．LiW．M．etal．Theinfluencefactorsofrecoveryoflowconcentrationnitrogenandphosphorusu-singstruvitebasedonsludgereduction．EnvironmentalEn-gineering201028547-50inChinese2．．20042217-10LiJ．Y．ZhengP．Applicationofstruviteprecipitationinremovalofphosphorusandnitrogenfromwastewater．ChinaBiogas20042217-10inChinese3StratfulI．ScrimshawM．D．LesterJ．N．Conditionsin-fluencingtheprecipitationofmagnesimammoniumphos-phate．WaterＲesearch200135174191-41994．．2013321105-109ZhangQ．GaoN．ZhaoS．P．etal．Advanceofnitro-gen-phosphorusrecoverybystruvitecrystallization．SichuanEnvironment2013321105-109inChinese5OhlingerK．N．YoungT．M．SchroederE．D．Predic-tingstruviteformationindigestion．WaterＲesearch199832123607-36146．．20093585-8DongB．DuanN．N．HeQ．B．etal．Statusanddevel-opmentofstruvitecrystallizationforswinewastewatertreat-ment．TechnologyofWaterTreatment20093585-8inChinese7．．2007264526-530TongJ．ChenY．G．GuG．W．Ｒesentadvancesin-phosphorusremovalwithstruviteformation．ChemicalIn-dustryandEngineeringProgress2007264526-530inChinese962588DoyleJ．D．ParsonsS．A．Struviteformationcontrolandrecovery．WaterＲesearch200836163925-39409AlexandraH．KaiM．U．Struviteprecipitationfromurinewithelectrochemicalmagnesiumdosage．WaterＲeasearch2013471289-29910B