13.Kodi njira zodzitetezera poyezera CODCr ndi ziti?
Muyezo wa CODCr umagwiritsa ntchito potassium dichromate monga oxidant, silver sulfate monga chothandizira pansi pa acidic, kuwira ndi kutsitsimuka kwa maola awiri, kenaka kumasintha kukhala oxygen (GB11914-89) poyesa kudya kwa potassium dichromate. Mankhwala monga potassium dichromate, mercury sulfate ndi concentrated sulfuric acid amagwiritsidwa ntchito muyeso wa CODCr, womwe ungakhale wapoizoni kwambiri kapena wowononga, ndipo umafunika kutentha ndi reflux, choncho opaleshoniyo iyenera kuchitidwa mu fume hood ndipo iyenera kuchitidwa mosamala kwambiri. Zotayira zamadzimadzi Ziyenera kubwezeretsedwanso ndikutayidwa padera.
Pofuna kulimbikitsa okosijeni wathunthu wa zinthu zochepetsera m'madzi, siliva sulphate iyenera kuwonjezeredwa ngati chothandizira. Kuti siliva sulphate igawidwe mofanana, sulphate ya siliva iyenera kusungunuka mu sulfuric acid. Pambuyo pa kusungunuka kwathunthu (pafupifupi masiku awiri), acidification imayamba. sulfuric acid mu botolo la Erlenmeyer. Njira yoyezera dziko lonse imati 0.4gAg2SO4/30mLH2SO4 iyenera kuwonjezeredwa pa muyeso uliwonse wa CODCr (20mL madzi chitsanzo), koma deta yoyenera imasonyeza kuti zitsanzo za madzi ambiri, kuwonjezera 0.3gAg2SO4/30mLH2SO4 ndikokwanira, ndipo palibe chifukwa chochitira. gwiritsani ntchito Silver sulphate. Kwa zitsanzo za madzi onyansa omwe amayezedwa pafupipafupi, ngati pali kuwongolera kokwanira kwa data, kuchuluka kwa sulfate yasiliva kumatha kuchepetsedwa moyenera.
CODCr ndi chizindikiro cha zinthu zomwe zili m'zimbudzi, kotero kuti ma chloride ma ion ndi zinthu zochepetsera mpweya ziyenera kuchotsedwa poyezera. Pakusokonezedwa ndi zinthu zochepetsera organic monga Fe2+ ndi S2-, mtengo wa CODCr woyezedwa ukhoza kuwongoleredwa potengera kufunidwa kwa okosijeni kutengera kuchuluka kwake. Kusokoneza ma chloride ayoni Cl-1 nthawi zambiri amachotsedwa ndi mercury sulfate. Pamene ndalama zowonjezera ndi 0.4gHgSO4 pa 20mL madzi chitsanzo, kusokoneza 2000mg/L chloride ayoni akhoza kuchotsedwa. Kwa zitsanzo za madzi onyansa omwe amayezedwa pafupipafupi omwe ali ndi zigawo zokhazikika, ngati chloride ion zili zochepa kapena zitsanzo zamadzi zomwe zimakhala ndi dilution factor ndizokwera kwambiri, kuchuluka kwa mercury sulfate kumatha kuchepetsedwa moyenera.
14. Kodi njira yothandizira siliva sulfate ndi yotani?
Njira yothandizira ya silver sulfate ndi yakuti mankhwala omwe ali ndi magulu a hydroxyl muzinthu zamoyo amayamba kulowetsedwa ndi potaziyamu dichromate kukhala carboxylic acid mu sing'anga yolimba ya acidic. Mafuta opangidwa kuchokera ku hydroxyl organic matter amakhudzidwa ndi silver sulfate kupanga mafuta acid acid. Chifukwa cha zochita za maatomu asiliva, gulu la carboxyl limatha kupanga mosavuta mpweya woipa ndi madzi, ndipo nthawi yomweyo limapanga siliva watsopano wamafuta acid, koma atomu yake ya kaboni ndi imodzi yocheperako. Kuzungulira kumeneku kumabwereza, pang'onopang'ono kutulutsa zinthu zonse zamoyo kukhala carbon dioxide ndi madzi.
15.Kodi njira zopewera muyeso wa BOD5 ndi ziti?
Muyezo wa BOD5 nthawi zambiri umagwiritsa ntchito njira ya dilution ndi inoculation (GB 7488-87). Opaleshoniyo ndikuyika zitsanzo za madzi zomwe zasinthidwa, kuchotsa zinthu zapoizoni, ndi kuchepetsedwa (ndi inoculum yoyenerera yomwe ili ndi tizilombo toyambitsa matenda ngati kuli kofunikira). Mu botolo la chikhalidwe, sungani mumdima pa 20 ° C kwa masiku asanu. Poyesa kusungunuka kwa okosijeni m'miyeso ya madzi musanayambe komanso pambuyo pa chikhalidwe, mpweya wa okosijeni mkati mwa masiku a 5 ukhoza kuwerengedwa, ndiyeno BOD5 ikhoza kupezedwa pogwiritsa ntchito dilution factor.
Kutsimikiza kwa BOD5 ndiye zotsatira zolumikizana zachilengedwe ndi zamankhwala ndipo ziyenera kuchitidwa motsatira zomwe zanenedwa. Kusintha mkhalidwe uliwonse kudzakhudza kulondola ndi kufananiza kwa zotsatira zoyezera. Zinthu zomwe zimakhudza kutsimikiza kwa BOD5 zimaphatikizapo pH mtengo, kutentha, mtundu wa tizilombo toyambitsa matenda ndi kuchuluka kwake, mchere wa inorganic, mpweya wosungunuka ndi dilution factor, etc.
Zitsanzo za madzi zoyezetsa BOD5 ziyenera kudzazidwa ndi kusindikizidwa m'mabotolo a zitsanzo, ndikusungidwa mufiriji pa 2 mpaka 5 ° C mpaka kufufuzidwa. Nthawi zambiri, kuyezetsa kuyenera kuchitika mkati mwa maola 6 mutatenga zitsanzo. Mulimonsemo, nthawi yosungiramo zitsanzo za madzi sayenera kupitirira maola 24.
Poyezera BOD5 yamadzi otayira m'mafakitale, popeza madzi otayira m'mafakitale nthawi zambiri amakhala ndi okosijeni osasungunuka ndipo amakhala ndi zinthu zachilengedwe zomwe zimawonongeka kwambiri, kuti asunge chikhalidwe cha aerobic mubotolo lachikhalidwe, madziwo amayenera kuchepetsedwa (kapena kulowetsedwa ndi kuchepetsedwa). Opaleshoni imeneyi ndi mbali yaikulu ya muyezo dilution njira. Pofuna kutsimikizira kudalirika kwa zotsatira zoyezedwa, kumwa kwa okosijeni kwa madzi osungunuka pambuyo pa chikhalidwe kwa masiku 5 kuyenera kukhala kwakukulu kuposa 2 mg/L, ndipo mpweya wotsalira wosungunuka uyenera kukhala woposa 1 mg/L.
Cholinga chowonjezera njira ya inoculum ndikuonetsetsa kuti tizilombo toyambitsa matenda timayambitsa tizilombo toyambitsa matenda m'madzi. Kuchuluka kwa yankho la inoculum ndikwabwino kwambiri kotero kuti kumwa kwa okosijeni mkati mwa masiku asanu kumakhala kosakwana 0.1mg/L. Mukamagwiritsa ntchito madzi osungunuka okonzedwa ndi chitsulo chosungunula ngati madzi osungunula, kusamala kuyenera kuchitidwa kuti muwone zomwe zili mkati mwake kuti musalepheretse kubereka kwa tizilombo toyambitsa matenda ndi metabolism. Pofuna kuonetsetsa kuti mpweya wosungunuka m'madzi osungunuka uli pafupi ndi machulukidwe, mpweya woyeretsedwa kapena mpweya wabwino ukhoza kuyambitsidwa ngati kuli kofunikira, ndiyeno kuikidwa mu chofungatira cha 20oC kwa nthawi yoti mugwirizane ndi mpweya wochepa wa mpweya. mpweya.
Zomwe zimapangidwira zimatsimikiziridwa potengera mfundo yakuti mpweya wa okosijeni ndi waukulu kuposa 2 mg / L ndipo mpweya wotsalira wosungunuka ndi waukulu kuposa 1 mg / L pambuyo pa masiku 5 a chikhalidwe. Ngati dilution factor ndi yayikulu kwambiri kapena yaying'ono kwambiri, mayesowo amalephera. Ndipo chifukwa kuzungulira kwa kusanthula kwa BOD5 ndikwatali, zikangochitika zofanana, sizingayesedwenso momwe zilili. Poyamba kuyeza BOD5 ya madzi otayira m'mafakitale ena, mutha kuyeza kaye CODCr yake, ndiyeno tchulani zomwe zilipo kale zowunikira madzi otayidwa okhala ndi madzi ofananirako kuti adziwe poyambira mtengo wa BOD5/CODCr wa madziwo kuti ayezedwe, ndikuwerengera. pafupifupi pafupifupi BOD5 kutengera izi. ndi kudziwa dilution factor.
Kwa zitsanzo zamadzi zomwe zili ndi zinthu zomwe zimalepheretsa kapena kupha zochita za kagayidwe kazakudya za tizilombo ta aerobic, zotsatira za kuyeza mwachindunji BOD5 pogwiritsa ntchito njira wamba zidzachoka pamtengo weniweni. Kukonzekera kofananira kuyenera kuchitidwa musanayambe kuyeza. Zinthu izi ndi zinthu zimakhudza kutsimikiza kwa BOD5. Kuphatikizira zitsulo zolemera ndi zinthu zina zapoizoni kapena organic, chlorine yotsalira ndi zinthu zina zotulutsa okosijeni, mtengo wa pH womwe ndi wokwera kwambiri kapena wotsika kwambiri, ndi zina zambiri.
16. N’chifukwa chiyani kuli koyenera kuti tizitemera poyezera BOD5 ya madzi oipa a m’mafakitale? Kodi katemera?
Kutsimikiza kwa BOD5 ndi njira yogwiritsira ntchito mpweya wa okosijeni. Tizilombo tating'onoting'ono ta m'madzi timagwiritsa ntchito zinthu zamoyo zomwe zili m'madzi monga zakudya kuti zikule ndi kuberekana. Panthaŵi imodzimodziyo, amawola zinthu zakuthupi ndi kuwononga mpweya wosungunuka m’madzi. Choncho, chitsanzo cha madzi chiyenera kukhala ndi tizilombo tating'onoting'ono tomwe titha kusokoneza zinthu zamoyo zomwe zili mmenemo. luso la ma microorganisms.
Madzi otayira m'mafakitale nthawi zambiri amakhala ndi zinthu zapoizoni zosiyanasiyana, zomwe zingalepheretse kugwira ntchito kwa tizilombo toyambitsa matenda. Choncho, chiwerengero cha tizilombo tating'onoting'ono m'madzi otayira m'mafakitale ndi ochepa kwambiri kapena kulibe. Ngati njira wamba zoyezera zimbudzi zokhala ndi tizilombo tating'onoting'ono zam'tawuni zikugwiritsidwa ntchito, zomwe zili m'madzi otayidwa sizingadziwike, kapena kukhala zochepa. Mwachitsanzo, kwa zitsanzo za madzi omwe athandizidwa ndi kutentha kwambiri ndi kutsekereza komanso pH yake ndi yokwera kwambiri kapena yotsika kwambiri, kuwonjezera pa kutenga njira zochizira, monga kuziziritsa, kuchepetsa ma bactericides, kapena kusintha pH mtengo, kuti zitsimikizire. kulondola kwa muyeso wa BOD5, njira zogwira mtima ziyeneranso kuchitidwa. Katemera.
Poyezera BOD5 yamadzi owonongeka a mafakitale, ngati zinthu zomwe zili ndi poizoni ndi zazikulu kwambiri, mankhwala nthawi zina amagwiritsidwa ntchito kuchotsa; ngati madzi otayira ali acidic kapena amchere, ayenera kuchepetsedwa poyamba; ndipo kawirikawiri chitsanzo cha madzi chiyenera kuchepetsedwa chisanayambe kugwiritsidwa ntchito. Kutsimikiza ndi njira ya dilution. Kuonjezera mlingo woyenerera wa inoculum solution yomwe ili ndi tizilombo toyambitsa matenda tomwe timakhala m'madzi (monga thanki ya aeration yomwe imagwiritsidwa ntchito popangira madzi otayira m'mafakitale) ndikupangitsa kuti madziwo akhale ndi tizilombo tomwe timatha kuwononga organic. nkhani. Pansi pazikhalidwe zina zoyezera BOD5 zimakwaniritsidwa, tizilombo tating'onoting'ono tating'onoting'ono tating'onoting'ono timagwiritsidwa ntchito kuwola zinthu zachilengedwe m'madzi onyansa a mafakitale, ndipo kumwa kwa mpweya wamadzi am'madzi kumayezedwa kwa masiku 5 akulima, ndipo mtengo wa BOD5 wamadzi otayira m'mafakitale ukhoza kupezeka. .
Madzi osakanikirana a thanki ya aeration kapena kutayira kwa tanki yachiwiri yosungiramo zimbudzi ndi gwero labwino la tizilombo toyambitsa matenda kuti tidziwe BOD5 yamadzi onyansa omwe amalowa m'chimbudzi. Direct inoculation ndi zimbudzi m'nyumba, chifukwa pali pang'ono kapena palibe kusungunuka mpweya, sachedwa zikamera wa anaerobic tizilombo, ndipo amafuna nthawi yaitali kulima ndi acclimation. Choncho, njira iyi ya acclimated inoculum ndi yoyenera pamadzi ena otayira m'mafakitale omwe ali ndi zosowa zenizeni.
17. Ndi njira ziti zodzitetezera pokonzekera madzi osungunuka poyeza BOD5?
Ubwino wa madzi osungunuka ndiwofunika kwambiri pakulondola kwa zotsatira za muyeso wa BOD5. Choncho, pamafunika kuti mpweya wa okosijeni wa madzi osungunula opanda kanthu kwa masiku asanu ukhale wosachepera 0.2mg/L, ndipo ndi bwino kuulamulira pansi pa 0.1mg/L. Kumwa kwa okosijeni kwa madzi otsekemera otsekemera kwa masiku asanu kuyenera kukhala Pakati pa 0.3 ~ 1.0mg/L.
Chinsinsi chowonetsetsa kuti madzi osungunula ndi abwino kwambiri ndikuwongolera zinthu zotsika kwambiri za organic ndi zinthu zotsika kwambiri zomwe zimalepheretsa kuberekana kwa tizilombo toyambitsa matenda. Choncho, ndi bwino kugwiritsa ntchito madzi osungunuka ngati madzi osungunuka. Sikoyenera kugwiritsa ntchito madzi oyera opangidwa kuchokera ku utomoni wosinthanitsa ndi ayoni ngati madzi osungunula, chifukwa madzi osungunula nthawi zambiri Amakhala ndi zinthu zosiyanitsidwa ndi utomoni. Ngati madzi apampopi omwe amagwiritsidwa ntchito pokonzekera madzi osungunula ali ndi zinthu zina zowonongeka, kuti atetezedwe kukhalabe m'madzi osungunuka, kukonzekereratu kuchotsa mankhwala a organic kuyenera kuchitika musanayambe distillation. M'madzi osungunuka opangidwa kuchokera kuzitsulo zazitsulo, chidwi chiyenera kuperekedwa poyang'ana zitsulo za ayoni zomwe zili mmenemo kuti zipewe kulepheretsa kubereka ndi kagayidwe ka tizilombo toyambitsa matenda komanso kukhudza kulondola kwa zotsatira za muyeso wa BOD5.
Ngati madzi osungunula omwe amagwiritsidwa ntchito sakukwaniritsa zofunikira pakugwiritsa ntchito chifukwa ali ndi zinthu zachilengedwe, zotsatira zake zitha kuthetsedwa powonjezera inoculum yokwanira ya tanki yotulutsa mpweya ndikuisunga pa kutentha kapena 20oC kwa nthawi inayake. Kuchuluka kwa inoculation kumachokera pa mfundo yakuti kumwa mpweya m'masiku asanu ndi pafupifupi 0.1mg/L. Pofuna kupewa kubereka kwa algae, kusungirako kuyenera kuchitidwa m'chipinda chamdima. Ngati m'madzi osungunuka muli matope atatha kusungidwa, mphamvu yokhayo ingagwiritsidwe ntchito ndipo matope amatha kuchotsedwa ndi kusefera.
Pofuna kuonetsetsa kuti mpweya wosungunuka m'madzi osungunula uli pafupi ndi machulukitsidwe, ngati kuli kofunikira, pampu ya vacuum kapena ejector yamadzi ingagwiritsidwe ntchito pokoka mpweya woyeretsedwa, micro air compressor ingagwiritsidwenso ntchito kubaya mpweya woyeretsedwa, ndi mpweya. botolo lingagwiritsidwe ntchito poyambitsa mpweya wabwino, ndiyeno madzi okosijeni Madzi osungunuka amaikidwa mu chofungatira cha 20oC kwa nthawi inayake kuti mpweya wosungunuka ukhale wofanana. Madzi osungunuka omwe amaikidwa m'chipinda chotsika kutentha m'nyengo yozizira akhoza kukhala ndi mpweya wambiri wosungunuka, ndipo zosiyana ndi zomwe zimachitika m'nyengo zotentha kwambiri m'chilimwe. Choncho, pamene pali kusiyana kwakukulu pakati pa kutentha kwa chipinda ndi 20oC, iyenera kuikidwa mu chofungatira kwa nthawi kuti chikhazikike ndi chikhalidwe cha chikhalidwe. oxygen partial pressure balance.
18. Kodi mungadziwe bwanji dilution factor poyeza BOD5?
Ngati dilution factor ndi yayikulu kwambiri kapena yaying'ono kwambiri, kugwiritsa ntchito okosijeni m'masiku 5 kumatha kukhala kocheperako kapena kuchulukirachulukira, kupitilira kuchuluka kwa okosijeni wamba ndikupangitsa kuyesako kulephera. Popeza kuti miyeso ya BOD5 ndi yayitali kwambiri, ngati izi zichitika, sizingayesedwenso momwe zilili. Chifukwa chake, chidwi chachikulu chiyenera kuperekedwa pakutsimikiza kwa dilution factor.
Ngakhale mapangidwe amadzi otayira m'mafakitale ndi ovuta, chiŵerengero cha mtengo wake wa BOD5 ku mtengo wa CODCr nthawi zambiri chimakhala pakati pa 0.2 ndi 0.8. Chiyerekezo cha madzi otayira kuchokera ku kupanga mapepala, kusindikiza ndi utoto, ndi mafakitale a mankhwala ndi otsika, pamene chiŵerengero cha madzi oipa kuchokera ku makampani a zakudya ndi apamwamba. Poyezera BOD5 yamadzi otayira omwe ali ndi zinthu za granular organic, monga madzi onyansa ambewu ya distiller, chiŵerengerocho chidzakhala chochepa kwambiri chifukwa tinthu tating'onoting'ono timadumphira pansi pa botolo la chikhalidwe ndipo sangatenge nawo mbali pa biochemical reaction.
Kutsimikiza kwa dilution factor kumachokera ku zikhalidwe ziwiri zomwe poyeza BOD5, mpweya wa okosijeni m'masiku a 5 uyenera kukhala waukulu kuposa 2mg / L ndipo mpweya wotsalira wosungunuka ukhale waukulu kuposa 1mg / L. DO mu botolo la chikhalidwe tsiku lotsatira kuchepetsedwa ndi 7 mpaka 8.5 mg/L. Poganiza kuti kugwiritsa ntchito okosijeni m'masiku a 5 ndi 4 mg / L, dilution factor ndi chinthu chamtengo wapatali cha CODCr ndi ma coefficients atatu a 0.05, 0.1125, ndi 0.175 motsatira. Mwachitsanzo, mukamagwiritsa ntchito botolo la chikhalidwe cha 250mL kuyeza BOD5 ya chitsanzo cha madzi ndi CODCr ya 200mg/L, zinthu zitatu zochepetsera ndi: ①200×0.005=10 nthawi, ②200×0.1125=22.5 nthawi, ndi ③200×17. 35 nthawi. Ngati njira ya dilution yachindunji ikugwiritsidwa ntchito, kuchuluka kwa zitsanzo zamadzi zomwe zatengedwa ndi: ①250÷10=25mL, ②250÷22.5≈11mL, ③250÷35≈7mL.
Ngati mutenga zitsanzo ndi chikhalidwe motere, padzakhala 1 mpaka 2 yoyezera zotsatira za okosijeni zomwe zimagwirizana ndi mfundo ziwirizi. Ngati pali mitundu iwiri ya dilution yomwe ikugwirizana ndi mfundo zomwe zili pamwambazi, mtengo wake uyenera kutengedwa powerengera zotsatira. Ngati mpweya wotsala wosungunuka uli wochepera 1 mg/L kapena ziro, chiŵerengero cha dilution chiyenera kuwonjezeka. Ngati kusungunuka kwa okosijeni panthawi ya chikhalidwe kuli kochepa kuposa 2mg / L, chotheka chimodzi ndi chakuti dilution factor ndi yaikulu kwambiri; Kuthekera kwina ndikuti tizilombo tating'onoting'ono tating'onoting'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tambiri. Panthawi imeneyi, pangakhalenso mavuto ndi zinthu zazikulu dilution. Botolo la chikhalidwe limadya mpweya wosungunuka kwambiri.
Ngati madzi osungunula ndi madzi otsekemera amadzimadzi, popeza kumwa kwa oxygen kwa madzi opanda kanthu ndi 0.3 ~ 1.0mg/L, ma coefficients a dilution ndi 0.05, 0.125 ndi 0.2 motsatira.
Ngati mtengo wake wa CODCr kapena pafupifupi mtundu wa madziwo umadziwika, zitha kukhala zosavuta kusanthula mtengo wake wa BOD5 molingana ndi zomwe zili pamwambapa. Pamene mtundu wa CODCr wa zitsanzo za madzi sudziwika, kuti ufupikitse nthawi yowunikira, ukhoza kuganiziridwa panthawi ya kuyeza kwa CODCr. Njira yeniyeni ndi: choyamba konzani yankho lokhazikika lomwe lili ndi 0.4251g potaziyamu phthalate pa lita (mtengo wa CODCr wa yankho ili ndi 500mg/L), ndiyeno muchepetse molingana ndi milingo ya CODCr ya 400mg/L, 300mg/L, ndi 200 mg. /L, 100mg/L dilute solution. Pipette 20.0 mL ya njira yokhazikika yokhala ndi mtengo wa CODCr wa 100 mg/L mpaka 500 mg/L, onjezani zopangira zinthu molingana ndi njira yanthawi zonse, ndikuyesa mtengo wa CODCr. Mukatenthetsa, kuwiritsa ndi kubwezeretsanso kwa mphindi 30, kuziziritsa mwachibadwa mpaka kutentha kwa chipinda, kenako kuphimba ndi kusunga kuti mukonzekere mndandanda wamtundu wa colorimetric. Poyesa mtengo wa CODCr wa chitsanzo cha madzi molingana ndi njira yanthawi zonse, pamene kutentha kwa madzi kumapitirira kwa mphindi 30, yerekezerani ndi ndondomeko yamtundu wa CODCr yamtengo wapatali kuti muyese mtengo wa CODCr wa chitsanzo cha madzi, ndi kudziwa dilution factor poyesa BOD5 kutengera izi. . Pakusindikiza ndi kupenta, kupanga mapepala, mankhwala ndi madzi ena otayira m'mafakitale omwe ali ndi zinthu zakuthupi zovuta kugaya, ngati kuli kofunikira, pendani colorimetric mutatha kuwiritsa ndikusinthanso kwa mphindi 60.
Nthawi yotumiza: Sep-21-2023
