Imfuno yeoksijini yekhemikhali (COD): irula engabonakaliyo yomgangatho wamanzi asempilweni

Kwimekobume esihlala kuyo, ukhuseleko lomgangatho wamanzi likhonkco elibalulekileyo. Nangona kunjalo, umgangatho wamanzi awusoloko ubonakala, kwaye ufihla iimfihlelo ezininzi esingenakuzibona ngokuthe ngqo ngamehlo ethu. Imfuno ye-oksijini ye-Chemical (COD), njengeparameter ephambili kuhlalutyo lomgangatho wamanzi, ifana nomlawuli ongabonakaliyo onokusinceda silinganise kwaye sihlolisise umxholo wokungcola kwezinto eziphilayo emanzini, ngaloo ndlela sityhila imeko yokwenene yomgangatho wamanzi.
Khawufane ucinge ukuba umjelo wamanzi amdaka ekhitshini lakho uvaliwe, ngaba kuya kubakho ivumba elibi? Elo vumba ngokwenene liveliswa kukubiliswa kwezinto eziphilayo kwindawo engenawo umoya-mpilo. I-COD isetyenziselwa ukulinganisa ukuba ingakanani ioksijini efunekayo xa ezi zinto ziphilayo (kunye nezinye izinto ezixutywe neoksijini, ezifana ne-nitrite, ityuwa ye-ferrous, i-sulfide, njl.njl.) zifakwe i-oxidized emanzini. Ukubeka nje, okukhona ixabiso leCOD liphezulu, kokukhona amanzi anzulu angcoliswa yindalo ephilayo.
Ukufunyaniswa kwe-COD kunokubaluleka okubonakalayo okubaluleke kakhulu. Sesinye sezibonakaliso ezibalulekileyo zokulinganisa iqondo lokungcoliseka kwamanzi. Ukuba ixabiso le-COD liphezulu kakhulu, lithetha ukuba i-oksijini echithwe emanzini iya kuchithwa ngobuninzi. Ngale ndlela, izinto eziphilayo zasemanzini ezifuna i-oksijini ukuze ziphile (ezifana neentlanzi kunye ne-shrimp) ziya kujongana nengxaki yokuphila, kwaye zingakhokelela kwinto "yamanzi afileyo", ebangela ukuba i-ecosystem yonke iwele. Ke ngoko, ukuvavanywa rhoqo kwe-COD kufana nokwenza uvavanyo lomzimba lomgangatho wamanzi, ukufumanisa nokusombulula iingxaki ngexesha elifanelekileyo.
Indlela yokubona ixabiso leCOD leisampulu zamanzi? Oku kufuna ukusetyenziswa “kwezixhobo” zobungcali.
Eyona ndlela isetyenziswa ngokuqhelekileyo yindlela ye-potassium dichromate. Ivakala inzima, kodwa umgaqo ulula kakhulu:
Inqanaba lokulungiselela: Okokuqala, kufuneka sithathe umlinganiselo othile wesampulu yamanzi, emva koko songeze i-potassium dichromate, i-“super oxidant”, kwaye songeze i-sulfate yesilivere njenge-catalyst ukwenza ukusabela ngokucokisekileyo. Ukuba kukho i-chloride ion emanzini, kufuneka zikhuselwe nge-mercuric sulfate.
Ukufudumeza i-reflux: Okulandelayo, fudumeza le mixube kunye kwaye uyivumele isabele kwiasidi yesulfuric ebilayo. Le nkqubo ifana nokunika isampuli yamanzi "i-sauna", ityhila ukungcola.
Uhlalutyo lwe-Titration: Emva kokuba impendulo iphelile, siya kusebenzisa i-ammonium ferrous sulfate, "i-agent yokunciphisa", ukuthoba i-potassium dichromate eseleyo. Ngokubala ukuba i-ejenti yokunciphisa ingakanani idliwe, sinokwazi ukuba ingakanani i-oksijini esetyenzisiweyo ukukhupha izinto ezingcolileyo emanzini.
Ukongeza kwindlela ye-potassium dichromate, kukho ezinye iindlela ezifana nendlela ye-potassium permanganate. Baneenzuzo zabo, kodwa injongo iyafana, kukulinganisa ngokuchanekileyo ixabiso leCOD.
Okwangoku, indlela ye-spectrophotometry yokugaya ngokukhawuleza isetyenziselwa ukufumanisa i-COD kwimarike yasekhaya. Le yindlela yokufumanisa i-COD ekhawulezayo esekelwe kwindlela ye-potassium ye-dichromate, kwaye isebenzisa umgangatho womgaqo-nkqubo "HJ / T 399-2007 Ukumiselwa koMgangatho waManzi we-Chemical Oxygen Demand Rapid Digestion Spectrophotometry". Ukususela ngo-1982, uMnu. Ji Guoliang, umsunguli we-Lianhua Technology, uye wavelisa i-COD yokugaya ngokukhawuleza i-spectrophotometry kunye nezixhobo ezinxulumene nazo. Emva kweminyaka engaphezu kwe-20 yokukhuthazwa kunye nokuthandwa, ekugqibeleni yaba ngumgangatho welizwe jikelele wokusingqongileyo ngo-2007, ukuzisa ukubhaqwa kwe-COD kwixesha lokufunyanwa ngokukhawuleza.
I-COD ye-spectrophotometry yokugaya ngokukhawuleza eyenziwe yi-Lianhua Technology inokufumana iziphumo ezichanekileyo ze-COD kwimizuzu engama-20.
1. Thatha i-2.5 ml yesampuli, yongeza i-reagent D kunye ne-reagent E, kwaye ugubungele kakuhle.
2. Fudumeza i-COD digester ukuya kuma-degrees angama-165, uze ubeke isampuli kwaye ugaye imizuzu eyi-10.
3. Emva kokuba ixesha liphelile, khupha isampuli kwaye uyipholise imizuzu emi-2.
4. Yongeza i-2.5 ml yamanzi adibeneyo, gubungela kakuhle kwaye uyipholise emanzini imizuzu emi-2.
5. Beka isampuli kwiIfotomitha ye-CODye colorimetry. Akukho balo lufunekayo. Iziphumo ziboniswa ngokuzenzekelayo kwaye ziprintwe. Ifanelekile kwaye iyakhawuleza.