46. Chii chinonzi oksijeni yakanyungudutswa?
Okisijeni yakanyungudika DO (pfupiso yeOkisijeni Yakanyungudutswa muChirungu) inomiririra huwandu hweokisijeni yakanyungudutswa mumvura, uye chikamu img/L. Iyo yakazadzwa yemukati yeokisijeni yakanyungudika mumvura inoenderana nekupisa kwemvura, kumanikidzwa kwemhepo uye kemikari yemvura. Pane imwe mhepo yemhepo, iyo okisijeni inoputika kana yakanyungudutswa okisijeni mumvura yakasvibiswa inosvika pakuzara pa0oC i14.62mg/L, uye pa20oC i9.17mg/L. Kuwedzera kwekushisa kwemvura, kuwedzera kwemunyu, kana kuderera kwemhepo yemhepo kuchaita kuti iyo yakanyungudutswa yeokisijeni iri mumvura iderere.
Okisijeni yakanyungudika chinhu chakakosha pakurarama nekuberekana kwehove uye mabhakitiriya eaerobic. Kana iyo okisijeni yakanyungudika yakaderera kupfuura 4mg/L, zvichave zvakaoma kuti hove dzirarame. Kana mvura yakasvibiswa neorganic matter, oxidation yeorganic matter neaerobic microorganisms inopedza iyo yakanyungudika mumvura. Kana isingakwanisi kuzadzikiswa kubva kumhepo nenguva, iyo okisijeni yakanyungudika mumvura inoderera zvishoma nezvishoma kusvikira yava pedyo ne0, zvichiita kuti nhamba huru yeanaerobic microorganisms iwande. Ita kuti mvura iite dema uye kunhuwa.
47. Ndedzipi nzira dzinowanzoshandiswa pakuyera okisijeni yakanyungudika?
Kune nzira mbiri dzinowanzo shandiswa pakuyera okisijeni yakanyungudika, imwe iodhiometric nzira uye nzira yekururamisa kwayo (GB 7489–87), uye imwe inzira ye electrochemical probe (GB11913–89). Iyo iodometric nzira inokodzera kuyera sampuli dzemvura neokisijeni yakanyungudika yakakura kupfuura 0.2 mg/L. Kazhinji, iyo iodometric nzira inokodzera chete kuyera okisijeni yakanyungudika mumvura yakachena. Pakuyera okisijeni yakanyungudika mumvura yetsvina yemumaindasitiri kana matanho akasiyana-siyana emiti yekuchenesa tsvina, iodine yakagadziridzwa inofanira kushandiswa. quantitative nzira kana electrochemical nzira. Muganho wakaderera wekutsunga we electrochemical probe nzira inoenderana nechiridzwa chinoshandiswa. Kune kunyanya mhando mbiri: membrane electrode nzira uye membraneless electrode nzira. Kazhinji akakodzera kuyera masampuli emvura ane okisijeni yakanyungudika yakakura kupfuura 0.1mg/L. Iyo yepamhepo DO mita yakamisikidzwa uye inoshandiswa mumatangi emhepo uye dzimwe nzvimbo mumiti yekuchenesa tsvina inoshandisa nzira ye membrane electrode kana membrane-shoma electrode nzira.
Nheyo yakakosha yeiyo iodometric nzira ndeyekuwedzera manganese sulfate uye alkaline potassium iodide kumuenzaniso wemvura. Okisijeni yakanyungudutswa mumvura inookisisa yakaderera-valent manganese kune yakakwirira-valent manganese, ichigadzira yakasviba precipitate ye tetravalent manganese hydroxide. Mushure mekuwedzera asidhi, iyo yebrown precipitate inonyungudika uye Inopindirana neiyo iodide ion kugadzira iyo iodine yemahara, uye yobva yashandisa starch sechiratidzo uye inonongedza iyo iodine yemahara nesodium thiosulfate kuverenga iyo yakanyungudika oksijeni zvirimo.
Kana sampu yemvura ine ruvara kana ine organic matter inogona kuita neiodine, haina kukodzera kushandisa iodometric nzira uye nzira yayo yekugadzirisa kuyera iyo yakanyungudika okisijeni mumvura. Panzvimbo iyoyo, iyo oxygen-sensitive film electrode kana membrane-shoma electrode inogona kushandiswa kuyerwa. Iokisijeni-sensitive electrode ine maelectrode maviri esimbi akabatana neanotsigira electrolyte uye inosarudza permeable membrane. Iyo membrane inogona kungopfuura kuburikidza neokisijeni nemamwe magasi, asi mvura nezvinhu zvinonyungudika mairi hazvigone kupfuura. Iyo okisijeni inopfuura nemu membrane inoderedzwa pa electrode. Iyo isina kusimba yekuparadzira ikozvino inogadzirwa, uye saizi yeazvino inoenzana neyakanyungudika oksijeni yemukati pane imwe tembiricha. Iyo electrode isina firimu inoumbwa neyakakosha sirivha alloy cathode uye simbi (kana zingi) anode. Iyo haishandise firimu kana electrolyte, uye hapana polarization voltage inowedzerwa pakati pematanda maviri. Inongotaurirana chete nemapango maviri kuburikidza neyakayerwa aqueous solution yekugadzira bhatiri rekutanga, uye mamorekuru eokisijeni ari mumvura ari Kuderedzwa kunoitwa zvakananga pane cathode, uye kudzikiswa kwazvino kunogadzirwa kunoenderana neokisijeni yemukati mune mhinduro iri kuyerwa. .
48. Sei iyo yakanyungudika yeokisijeni chiratidzo chiri chimwe chezviratidzo zvakakosha zvenguva dzose kushanda kwetsvina yebhayoloji yekurapa system?
Kuchengeta imwe huwandu hweokisijeni yakanyungudika mumvura ndiyo mamiriro ekutanga ekupona uye kuberekana kweaerobeic zvipenyu zvemumvura. Naizvozvo, iyo yakanyungudika yeokisijeni chiratidzo zvakare chimwe chezviratidzo zvakakosha zvekushanda kwakajairwa kwesewage biological treatment system.
The aerobic biological treatment device inoda kuti okisijeni yakanyungudika mumvura ive pamusoro pe 2 mg/L, uye anaerobic biological treatment device inoda kuti oxygen yakanyungudika ive pasi pe0.5 mg/L. Kana iwe uchida kupinda iyo yakakodzera methanogenesis nhanho, zviri nani kusava neanoona yakanyungudutswa okisijeni (ye0), uye kana chikamu A cheA/O chirongwa chiri mune anoxic mamiriro, iyo yakanyungudutswa okisijeni inodiwa 0.5 ~ 1mg/L. . Kana tsvina inobva kune yechipiri sedimentation tank yeiyo aerobic biological method yakwana, iyo yakanyungudutswa yeokisijeni inenge isiri pasi pe1mg/L. Kana yakaderera (<0.5mg/L) kana kukwirisa (mhepo aeration nzira>2mg/L), zvinokonzeresa kuyerera kwemvura. Hunhu hwemvura hunodzikira kana kutopfuura mwero. Naizvozvo, kutarisisa kuzere kunofanirwa kubhadharwa pakutarisa iyo yakanyungudika yeokisijeni mukati meiyo biological kurapwa mudziyo uye tsvina yetangi rayo rekunyungudutsa.
Iodometric titration haina kukodzera kuongororwa pa-saiti, uye haigone kushandiswa kuenderera mberi nekutarisa kana pasaiti kugadzwa kweokisijeni yakanyungudika. Mukuenderera mberi kwekutarisa kweokisijeni yakanyungudika mumagadzirirwo ekuchenesa tsvina, nzira ye membrane electrode mu electrochemical method inoshandiswa. Kuti urambe uchibata shanduko muDO yemvura yakasanganiswa mutangi reaeration panguva yekuchenesa tsvina munguva chaiyo, online electrochemical probe DO mita inowanzo shandiswa. Panguva imwecheteyo, iyo DO mita zvakare chikamu chakakosha cheotomatiki kudzora uye kugadzirisa sisitimu yeokisijeni yakanyungudika muaeration tank. Nokuti kugadzirisa uye kutonga system inoita basa rinokosha mukushanda kwayo kwakajairika. Panguva imwecheteyo, ihwowo hwaro hwakakosha hwevashandisi vezvekugadzirisa uye kudzora kushanda kwakajairwa kwesewage biological treatment.
49. Ndeapi matanho ekuyera kuyera okisijeni yakanyungudika ne iodometric titration?
Kutarisirwa kwakakosha kunofanirwa kutorwa pakuunganidza sampuli dzemvura yekuyera oxygen yakanyungudika. Mienzaniso yemvura haifaniri kunge yakabatana nemhepo kwenguva yakareba uye haifaniri kubvongodzwa. Paunenge uchitora sampling mutangi rekuunganidza mvura, shandisa 300 ml girazi-rakashongedzerwa rakatetepa-muromo wakanyungudika bhodhoro reokisijeni, uye kuyera uye kurekodha tembiricha yemvura panguva imwe chete. Uyezve, paunenge uchishandisa iodometric titration, kunze kwekusarudza imwe nzira yekubvisa kupindira mushure mekuenzanisa, nguva yekuchengetedza inofanira kupfupiswa sezvinobvira, uye zvakanakisisa kuongorora pakarepo.
Kuburikidza nekuvandudzwa mune tekinoroji nemidziyo uye nerubatsiro rwezviridzwa, iodometric titration inoramba iri nzira chaiyo uye yakavimbika yetitration yekuongororwa kweokisijeni yakanyungudika. Kuti ubvise pesvedzero yezvinhu zvakasiyana-siyana zvinokanganisa mumasampuli emvura, kune nzira dzakati wandei dzekugadzirisa iodometric titration.
Oxides, reductants, organic matter, etc. zviripo mumvura samples zvinokanganisa iodometric titration. Mamwe maoxidants anogona kupatsanura iodide kuita iodine (kupindira kwakanaka), uye zvimwe zvinoderedza zvinogona kuderedza iodine kuita iodide (kukanganisa kunokanganisa). kupindira), kana iyo oxidized manganese precipitate iine acidified, zvinhu zvakawanda zveorganic zvinogona kuve zvishoma oxidized, zvichigadzira zvikanganiso zvisina kunaka. Iyo azide kugadzirisa nzira inogona kunyatsobvisa kupindira kwe nitrite, uye kana sampu yemvura ine yakaderera-valent iron, iyo potassium permanganate kugadzirisa nzira inogona kushandiswa kubvisa kupindira. Kana sampu yemvura iine ruvara, algae, uye zvakaturikwa zvakasimba, iyo alum flocculation kururamisa nzira inofanira kushandiswa, uye copper sulfate-sulfamic acid flocculation kugadzirisa nzira inoshandiswa kuona yakanyungudika okisijeni yemusanganiswa wakagadzirwa sludge.
50. Ndedzipi dziviriro dzekuyera okisijeni yakanyungudika uchishandisa nzira yakaonda yefirimu re electrode?
Iyo membrane electrode ine cathode, anode, electrolyte uye membrane. Iyo electrode cavity yakazadzwa neKCl mhinduro. Iyo membrane inopatsanura electrolyte kubva kumvura sampuli kuyerwa, uye okisijeni yakanyungudika inopinda uye inopararira nemukati memembrane. Mushure mokunge DC yakagadziriswa polarization voltage ye 0.5 kusvika ku 1.0V inoshandiswa pakati pematanda maviri, okisijeni yakanyungudutswa mumvura yakayerwa inopfuura nepakati pefirimu uye inoderedzwa pa cathode, zvichiita kuti kupararira kwemazuva ano kuenzane nekugadzirisa oksijeni.
Mafirimu anowanzo shandiswa ipolyethylene uye fluorocarbon mafirimu anogona kubvumira mamorekuru eokisijeni kupfuura uye ane zvinhu zvakagadzikana. Nokuti iyo firimu inogona kupinda mumagasi akasiyana-siyana, mamwe magasi (akadai seH2S, SO2, CO2, NH3, nezvimwewo) ari pa electrode inoratidza. Hazvisi nyore kuti depolarize, izvo zvinoderedza kunzwisiswa kwe electrode uye kutungamirira mukutsauka mumigumisiro yekuyera. Mafuta uye girizi mumvura yakayerwa uye tupukanana mutangi reaeration kazhinji anonamatira kune membrane, zvichikanganisa zvakanyanya kuyerwa kwechiyero, saka kuchenesa nguva dzose uye calibration zvinodiwa.
Naizvozvo, membrane electrode yakanyungudutswa okisijeni analyzers anoshandiswa mumaseji ekuchenesa masisitimu anofanirwa kushandiswa zvakanyatsoenderana neanogadzira nzira dzekugadzirisa, uye kuchenesa nguva dzose, calibration, electrolyte replenishment, uye electrode membrane kutsiva kunodiwa. Paunenge uchitsiva firimu, unofanira kuzviita nokungwarira. Kutanga, iwe unofanirwa kudzivirira kusvibiswa kwezvinhu zvinonzwisisika. Chechipiri, chenjerera kuti usasiya mabhuru madiki pasi pefirimu. Zvikasadaro, iyo yakasara ikozvino ichawedzera uye inokanganisa kuyerwa kwemhedzisiro. Kuti ive nechokwadi chechokwadi data, kuyerera kwemvura pa membrane electrode kuyerwa point kunofanirwa kuve nehumwe dhigirii remhirizhonga, kureva kuti, mhinduro yebvunzo inopfuura nepakati membrane pamusoro inofanira kunge iine mwero wakakwana wekuyerera.
Kazhinji, mweya kana masampuli ane anozivikanwa DO kusungwa uye masampuli asina DO anogona kushandiswa kudzora calibration. Ehezve, zvakanakisa kushandisa sampu yemvura pasi pekuongororwa kwekugadzirisa. Pamusoro pezvo, imwe kana maviri mapoinzi anofanirwa kuongororwa nguva nenguva kuti aone data rekugadzirisa tembiricha.
Nguva yekutumira: Nov-14-2023
