1.Ammonia nitrogen yog dab tsi?
Ammonia nitrogen hais txog ammonia nyob rau hauv daim ntawv ntawm ammonia dawb (los yog non-ionic ammonia, NH3) los yog ionic ammonia (NH4+).Siab dua pH thiab ntau dua ntawm cov dawb ammonia;Ntawm qhov tsis sib xws, qhov feem ntawm ammonium ntsev yog siab.
Ammonia nitrogen yog cov khoom noj khoom haus hauv dej, uas tuaj yeem ua rau dej eutrophication, thiab yog cov pa oxygen tseem ceeb hauv dej, uas yog tshuaj lom rau cov ntses thiab qee cov kab mob hauv dej.
Qhov teeb meem tseem ceeb ntawm ammonia nitrogen rau cov kab mob hauv dej yog dawb ammonia, uas nws toxicity yog kaum ob lub sij hawm ntau dua li ntawm ammonium ntsev, thiab nce nrog nce alkalinity.Ammonia nitrogen toxicity yog ze ze rau tus nqi pH thiab dej kub ntawm cov dej hauv pas dej, feem ntau, qhov siab dua tus nqi pH thiab dej kub, qhov muaj zog toxicity.
Ob txoj kev rhiab heev colorimetric feem ntau siv los txiav txim siab ammonia yog cov txheej txheem Nessler reagent classical thiab phenol-hypochlorite txoj kev.Titrations thiab hluav taws xob txoj kev kuj tseem siv los txiav txim siab ammonia;Thaum cov ntsiab lus ammonia nitrogen siab, txoj kev distillation titration kuj tseem siv tau.(Cov qauv hauv tebchaws suav nrog Nath's reagent method, salicylic acid spectrophotometric, distillation - titration method)
2.Lub cev thiab tshuaj nitrogen tshem tawm cov txheej txheem
① Tshuaj los nag txoj kev
Tshuaj los nag txoj kev, tseem hu ua MAP nag lossis daus txoj kev, yog ntxiv magnesium thiab phosphoric acid los yog hydrogen phosphate rau cov dej khib nyiab uas muaj ammonia nitrogen, kom NH4 + nyob rau hauv cov dej khib nyiab reacts nrog Mg + thiab PO4- nyob rau hauv ib tug aqueous tov los tsim ammonium magnesium phosphate nag lossis daus. , cov mis mos molecular yog MgNH4P04.6H20, thiaj li ua tiav lub hom phiaj ntawm kev tshem tawm ammonia nitrogen.Magnesium ammonium phosphate, feem ntau hu ua struvite, tuaj yeem siv ua compost, av additive lossis hluav taws kub retardant rau cov khoom tsim.Qhov sib npaug ntawm cov tshuaj tiv thaiv yog raws li nram no:
Mg++ NH4 + + PO4 – = MgNH4P04
Lub ntsiab tseem ceeb cuam tshuam rau kev kho mob ntawm cov dej nag yog pH tus nqi, kub, ammonia nitrogen concentration thiab molar ratio (n(Mg+): n(NH4+): n(P04-)).Cov txiaj ntsig tau pom tias thaum pH tus nqi yog 10 thiab molar piv ntawm magnesium, nitrogen thiab phosphorus yog 1.2: 1: 1.2, kev kho mob zoo dua.
Siv magnesium chloride thiab disodium hydrogen phosphate ua cov neeg ua dej nag, cov txiaj ntsig tau pom tias kev kho mob zoo dua thaum pH tus nqi yog 9.5 thiab molar ratio ntawm magnesium, nitrogen thiab phosphorus yog 1.2: 1: 1.
Cov txiaj ntsig tau pom tias MgC12 + Na3PO4.12H20 yog qhov zoo dua rau lwm qhov sib xyaw ua ke ntawm cov dej nag.Thaum tus nqi pH yog 10.0, qhov kub yog 30 ℃, n(Mg +): n(NH4+): n(P04-) = 1: 1: 1, qhov loj concentration ntawm ammonia nitrogen nyob rau hauv cov dej khib nyiab tom qab stirring rau 30min yog txo. los ntawm 222mg / L ua ntej kev kho mob mus rau 17mg / L, thiab tus nqi tshem tawm yog 92.3%.
Cov txheej txheem los nag thiab dej ua kua membrane tau ua ke rau kev kho mob ntawm cov khoom siv tshuaj ammonia nitrogen cov dej khib nyiab.Nyob rau hauv cov xwm txheej ntawm kev ua kom zoo ntawm cov txheej txheem nag lossis daus, tshem tawm tus nqi ntawm ammonia nitrogen mus txog 98.1%, thiab tom qab ntawd kev kho mob ntxiv nrog cov yeeb yaj kiab ua kua txo cov ammonia nitrogen concentration rau 0.005g / L, ncav cuag lub teb chaws thawj-chav kawm emission standard.
Kev tshem tawm cov nyhuv ntawm divalent hlau ions (Ni +, Mn +, Zn +, Cu +, Fe +) uas tsis yog Mg + ntawm ammonia nitrogen nyob rau hauv qhov kev txiav txim ntawm phosphate tau tshawb xyuas.Cov txheej txheem tshiab ntawm CaSO4 nag lossis daus-MAP tau thov rau ammonium sulfate cov dej khib nyiab.Cov txiaj ntsig tau pom tias cov neeg tswj hwm NaOH ib txwm tuaj yeem hloov tau los ntawm cov txiv qaub.
Qhov kom zoo dua ntawm cov txheej txheem nag lossis daus yog tias thaum qhov concentration ntawm ammonia nitrogen cov dej khib nyiab siab, kev siv lwm txoj kev raug txwv, xws li txoj kev lom neeg, txoj kev tawg point chlorination, membrane cais txoj kev, ion txauv txoj kev, thiab lwm yam. Lub sijhawm no, chemical los nag txoj kev tuaj yeem siv rau kev kho mob ua ntej.Kev tshem tawm ntawm cov tshuaj los nag txoj kev zoo dua, thiab nws tsis txwv los ntawm qhov kub thiab txias, thiab kev ua haujlwm yooj yim.Lub precipitated sludge uas muaj magnesium ammonium phosphate tuaj yeem siv los ua cov chiv sib xyaw kom paub txog kev siv pov tseg, yog li offsetting ib feem ntawm tus nqi;Yog tias nws tuaj yeem ua ke nrog qee lub tuam txhab kev lag luam uas tsim cov dej khib nyiab phosphate thiab cov chaw lag luam uas tsim cov ntsev brine, nws tuaj yeem txuag cov nqi tshuaj thiab pab txhawb kev siv loj.
Qhov tsis zoo ntawm cov txheej txheem nag lossis daus yog vim muaj kev txwv ntawm cov khoom siv solubility ntawm ammonium magnesium phosphate, tom qab ammonia nitrogen hauv cov dej khib nyiab nce mus txog qee qhov concentration, cov nyhuv tshem tawm tsis pom tseeb thiab cov nqi nkag tau nce siab heev.Yog li ntawd, cov txheej txheem los nag yuav tsum tau siv nrog rau lwm txoj kev uas tsim nyog rau kev kho mob siab heev.Tus nqi ntawm cov reagent siv yog loj, cov sludge tsim yog loj, thiab cov nqi kho mob siab.Kev qhia txog cov tshuaj chloride ions thiab cov phosphorus residual thaum siv tshuaj tuaj yeem ua rau muaj kuab paug thib ob.
Lag luam wholesale Aluminium Sulfate Chaw tsim tshuaj paus thiab tsum |EVERBRIGHT (cnchemist.com)
② tshuab tawm txoj kev
Kev tshem tawm ntawm ammonia nitrogen los ntawm txoj kev tshuab yog los kho tus nqi pH rau alkaline, kom cov ammonia ion nyob rau hauv cov dej khib nyiab tau hloov mus rau ammonia, yog li nws feem ntau tshwm sim hauv daim ntawv dawb ammonia, thiab tom qab ntawd cov ammonia dawb raug muab tshem tawm. ntawm cov dej khib nyiab los ntawm cov cab kuj roj, thiaj li ua tiav lub hom phiaj ntawm kev tshem tawm ammonia nitrogen.Lub ntsiab tseem ceeb cuam tshuam rau lub tshuab ua haujlwm yog pH tus nqi, qhov kub thiab txias, roj-kua piv, roj ntws tus nqi, thawj zaug concentration thiab lwm yam.Tam sim no, txoj kev tshuab tshuab yog dav siv hauv kev kho cov dej khib nyiab nrog siab concentration ntawm ammonia nitrogen.
Kev tshem tawm cov ammonia nitrogen los ntawm cov av khib nyiab los ntawm txoj kev tshuab tshuab tau kawm.Nws tau pom tias qhov tseem ceeb ntawm kev tswj xyuas qhov ua tau zoo ntawm lub tshuab yog qhov kub, roj-kua piv thiab tus nqi pH.Thaum cov dej kub siab tshaj 2590, cov roj-kua piv yog kwv yees li 3500, thiab pH yog hais txog 10.5, qhov kev tshem tawm tuaj yeem ncav cuag ntau dua 90% rau cov khib nyiab pov tseg nrog cov ammonia nitrogen concentration siab txog 2000-4000mg / L.Cov txiaj ntsig tau pom tias thaum pH = 11.5, stripping kub yog 80cC thiab lub sijhawm stripping yog 120min, qhov tshem tawm ntawm ammonia nitrogen hauv cov dej khib nyiab tuaj yeem ncav cuag 99.2%.
Lub tshuab nqus-tawm efficiency ntawm siab concentration ammonia nitrogen wastewater yog nqa tawm los ntawm countercurrent tshuab-off pej thuam.Cov txiaj ntsig tau pom tias lub tshuab ua haujlwm tau nce ntxiv nrog qhov nce ntawm tus nqi pH.Qhov loj dua cov roj-kua piv yog, ntau dua qhov kev tsav tsheb ntawm ammonia stripping huab hwm coj hloov yog, thiab lub stripping efficiency kuj nce.
Kev tshem tawm ntawm ammonia nitrogen los ntawm txoj kev tshuab yog zoo, yooj yim rau kev khiav lag luam thiab tswj tau yooj yim.Cov cua tshuab ammonia nitrogen tuaj yeem siv los ua ib qho absorber nrog sulfuric acid, thiab cov nyiaj sulfuric acid generated tuaj yeem siv ua chiv.Txoj kev tshuab tshuab yog ib qho cuab yeej siv rau kev tshem tawm lub cev thiab tshuaj nitrogen tam sim no.Txawm li cas los xij, txoj kev tshuab tshuab muaj qee qhov tsis zoo, xws li kev ntsuas ntau zaus hauv lub tshuab hluav taws xob ntauwd, tsis muaj ammonia nitrogen tshem tawm efficiency ntawm qhov kub thiab txias, thiab cov pa phem thib ob tshwm sim los ntawm lub tshuab cua tshuab.Txoj kev tshuab tshuab feem ntau yog ua ke nrog lwm txoj kev kho ammonia nitrogen cov dej khib nyiab rau pretreat high-concentration ammonia nitrogen cov dej khib nyiab.
③ Break point chlorination
Cov txheej txheem ntawm kev tshem tawm ammonia los ntawm kev tawg cov ntsiab lus chlorination yog tias cov roj chlorine reacts nrog ammonia los tsim cov pa nitrogen tsis muaj teeb meem, thiab N2 khiav tawm mus rau hauv qhov chaw, ua rau cov tshuaj tiv thaiv txuas mus rau sab xis.Cov tshuaj tiv thaiv mis yog:
HOCl NH4 + + 1.5 -> 0.5 N2 H20 H++ Cl - 1.5 + 2.5 + 1.5)
Thaum cov roj chlorine hloov mus rau hauv cov dej khib nyiab mus rau ib qho chaw, cov ntsiab lus ntawm cov tshuaj dawb chlorine hauv dej yog tsawg, thiab cov concentration ntawm ammonia yog xoom.Thaum cov roj chlorine hla dhau qhov taw tes, cov tshuaj dawb chlorine hauv dej yuav nce ntxiv, yog li ntawd, lub ntsiab lus hu ua break point, thiab chlorination hauv lub xeev no hu ua break point chlorination.
Txoj kev so chlorination yog siv los kho cov dej khib nyiab tom qab ammonia nitrogen tshuab, thiab cov nyhuv kho yog cuam tshuam ncaj qha los ntawm pretreatment ammonia nitrogen tshuab.Thaum 70% ntawm ammonia nitrogen nyob rau hauv cov dej khib nyiab raug tshem tawm los ntawm cov txheej txheem tshuab thiab tom qab ntawd kho los ntawm kev tawg point chlorination, qhov loj ntawm ammonia nitrogen nyob rau hauv cov effluent yog tsawg dua 15mg / L.Zhang Shengli et al.coj simulated ammonia nitrogen cov dej khib nyiab nrog qhov loj ntawm 100mg / L raws li cov khoom tshawb fawb, thiab cov kev tshawb fawb tau pom tias cov ntsiab lus tseem ceeb thiab theem nrab cuam tshuam rau kev tshem tawm ammonia nitrogen los ntawm oxidation ntawm sodium hypochlorite yog qhov sib piv ntawm chlorine rau ammonia nitrogen, lub sijhawm tshuaj tiv thaiv, thiab tus nqi pH.
Txoj kev so chlorination txoj kev muaj siab nitrogen tshem tawm efficiency, qhov kev tshem tawm tuaj yeem ncav cuag 100%, thiab cov ammonia concentration hauv cov dej khib nyiab tuaj yeem txo mus rau xoom.Cov nyhuv yog ruaj khov thiab tsis cuam tshuam los ntawm qhov kub thiab txias;Cov cuab yeej siv nyiaj tsawg dua, cov lus teb sai thiab ua tiav;Nws muaj cov nyhuv sterilization thiab tshuaj tua kab mob ntawm lub cev dej.Txoj kev siv cov txheej txheem so chlorination yog qhov concentration ntawm ammonia nitrogen cov dej khib nyiab tsawg dua 40mg / L, yog li txoj kev so chlorination feem ntau yog siv rau kev kho mob siab heev ntawm ammonia nitrogen khib nyiab.Qhov yuav tsum tau muaj kev nyab xeeb siv thiab khaws cia yog siab, tus nqi kho mob siab, thiab cov khoom los ntawm chloramines thiab chlorinated organics yuav ua rau cov pa phem thib ob.
④ catalytic oxidation txoj kev
Catalytic oxidation txoj kev yog los ntawm qhov kev txiav txim ntawm catalyst, nyob rau hauv ib tug tej yam kub thiab siab, los ntawm huab cua oxidation, organic teeb meem thiab ammonia nyob rau hauv dej phwj tuaj yeem oxidized thiab decomposed rau hauv cov khoom tsis zoo xws li CO2, N2 thiab H2O, kom ua tiav lub hom phiaj ntawm kev huv.
Cov yam ntxwv cuam tshuam rau cov nyhuv ntawm catalytic oxidation yog catalyst yam ntxwv, kub, tshuaj tiv thaiv lub sij hawm, pH nqi, ammonia nitrogen concentration, siab, stirring siv thiab hais txog.
Cov txheej txheem degradation ntawm ozonated ammonia nitrogen tau kawm.Cov txiaj ntsig tau pom tias thaum pH tus nqi nce, ib hom HO radical uas muaj peev xwm oxidation muaj zog tau tsim, thiab tus nqi oxidation tau nrawm heev.Kev tshawb fawb qhia tias ozone tuaj yeem oxidize ammonia nitrogen rau nitrite thiab nitrite rau nitrate.Qhov concentration ntawm ammonia nitrogen hauv dej txo qis nrog lub sijhawm nce, thiab kev tshem tawm ntawm ammonia nitrogen yog li 82%.CuO-Mn02-Ce02 tau siv los ua cov khoom siv sib xyaw ua ke los kho cov dej ammonia nitrogen.Cov txiaj ntsig kev sim qhia tau hais tias kev ua haujlwm oxidation ntawm cov khoom siv hluav taws xob uas tau npaj tshiab tau txhim kho, thiab cov txheej txheem tsim nyog yog 255 ℃, 4.2MPa thiab pH = 10.8.Hauv kev kho ammonia nitrogen cov dej khib nyiab nrog qhov pib concentration ntawm 1023mg / L, qhov kev tshem tawm ntawm ammonia nitrogen tuaj yeem ncav cuag 98% hauv 150min, ncav cuag lub teb chaws theem nrab (50mg / L) tus qauv tso tawm.
Kev ua haujlwm catalytic ntawm zeolite txhawb TiO2 photocatalyst tau tshawb xyuas los ntawm kev kawm txog qhov degradation ntawm ammonia nitrogen hauv sulfuric acid daws.Cov txiaj ntsig tau pom tias qhov kev pom zoo ntawm Ti02 / zeolite photocatalyst yog 1.5g / L thiab lub sijhawm tshuaj tiv thaiv yog 4h nyob rau hauv ultraviolet irradiation.Kev tshem tawm tus nqi ntawm ammonia nitrogen los ntawm cov dej khib nyiab tuaj yeem ncav cuag 98.92%.Kev tshem tawm cov nyhuv ntawm cov hlau siab thiab nano-chin dioxide nyob rau hauv ultraviolet lub teeb ntawm phenol thiab ammonia nitrogen tau kawm.Cov txiaj ntsig tau pom tias qhov kev tshem tawm ntawm ammonia nitrogen yog 97.5% thaum pH = 9.0 yog siv rau cov tshuaj ammonia nitrogen nrog cov concentration ntawm 50mg / L, uas yog 7.8% thiab 22.5% siab dua cov hlau siab lossis Chine dioxide ib leeg.
Catalytic oxidation txoj kev muaj qhov zoo ntawm kev ua kom huv huv, txheej txheem yooj yim, thaj chaw me me, thiab lwm yam, thiab feem ntau yog siv los kho cov dej khib nyiab siab ammonia nitrogen.Daim ntawv thov nyuaj yog yuav ua li cas los tiv thaiv qhov poob ntawm catalyst thiab corrosion tiv thaiv cov cuab yeej.
⑤ electrochemical oxidation txoj kev
Electrochemical oxidation method yog hais txog txoj kev tshem tawm cov pa phem hauv dej los ntawm kev siv electrooxidation nrog catalytic.Qhov tsis txaus ntseeg yog qhov ceev tam sim no, Inlet txaus tus nqi, qhov hluav taws xob thiab lub sijhawm daws teeb meem.
Cov electrochemical oxidation ntawm ammonia-nitrogen cov dej khib nyiab hauv cov circulating flow electrolytic cell tau kawm, qhov zoo yog Ti / Ru02-TiO2-Ir02-SnO2 network hluav taws xob thiab qhov tsis zoo yog Ti network hluav taws xob.Cov txiaj ntsig tau pom tias thaum cov tshuaj chloride ion concentration yog 400mg / L, thawj zaug ammonia nitrogen concentration yog 40mg / L, tus nqi txaus siab yog 600mL / min, qhov ceev tam sim no yog 20mA / cm, thiab lub sijhawm electrolytic yog 90min, ammonia. nitrogen tshem tawm tus nqi yog 99.37%.Nws qhia tau hais tias electrolytic oxidation ntawm ammonia-nitrogen wastewater muaj ib tug zoo daim ntawv thov.
3. Biochemical nitrogen tshem tawm cov txheej txheem
① tag nrho nitrification thiab denitrification
Tag nrho cov txheej txheem nitrification thiab denitrification yog ib hom kev lom neeg uas tau siv los ntev rau tam sim no.Nws converts ammonia nitrogen nyob rau hauv dej khib nyiab rau hauv nitrogen los ntawm ib tug series ntawm cov tshuaj xws li nitrification thiab denitrification nyob rau hauv qhov kev txiav txim ntawm ntau yam kab mob, thiaj li mus cuag lub hom phiaj ntawm kev kho dej khib nyiab.Cov txheej txheem ntawm nitrification thiab denitrification kom tshem tawm ammonia nitrogen yuav tsum mus dhau ob theem:
Nitrification cov tshuaj tiv thaiv: Cov tshuaj tiv thaiv nitrification yog ua tiav los ntawm aerobic autotrophic microorganisms.Hauv lub xeev aerobic, inorganic nitrogen yog siv los ua cov nitrogen los hloov NH4 + rau NO2-, thiab tom qab ntawd nws tau oxidized rau NO3-.Cov txheej txheem nitrification tuaj yeem muab faib ua ob theem.Hauv theem ob, nitrite hloov mus rau nitrate (NO3-) los ntawm cov kab mob nitrifying, thiab nitrite hloov mus rau nitrate (NO3-) los ntawm cov kab mob nitrifying.
Cov tshuaj tiv thaiv denitrification: Cov tshuaj tiv thaiv denitrification yog cov txheej txheem uas denitrifying cov kab mob txo nitrite nitrogen thiab nitrate nitrogen rau gaseous nitrogen (N2) nyob rau hauv lub xeev ntawm hypoxia.Cov kab mob denitrifying yog cov kab mob heterotrophic, feem ntau ntawm cov kab mob amphictic.Nyob rau hauv lub xeev ntawm hypoxia, lawv siv oxygen nyob rau hauv nitrate raws li electron txais thiab organic teeb meem (BOD tivthaiv nyob rau hauv dej phwj) raws li electron pub los muab lub zog thiab yuav oxidized thiab stabilized.
Tag nrho cov txheej txheem nitrification thiab denitrification engineering daim ntawv thov feem ntau suav nrog AO, A2O, oxidation ditch, thiab lwm yam, uas yog ib txoj kev paub tab ntau dua siv hauv kev lag luam tshem tawm nitrogen lom.
Tag nrho cov txheej txheem nitrification thiab denitrification muaj qhov zoo ntawm cov nyhuv ruaj khov, kev ua haujlwm yooj yim, tsis muaj kuab paug thib ob thiab tus nqi qis.Cov qauv no kuj muaj qee qhov tsis zoo, xws li cov pa roj carbon monoxide yuav tsum tau ntxiv thaum C / N piv rau hauv cov dej khib nyiab tsawg, qhov kub thiab txias yuav tsum nruj, qhov ua tau zoo ntawm qhov kub tsawg, thaj tsam loj, qhov xav tau oxygen. yog qhov loj, thiab qee cov khoom tsis zoo xws li cov hlau hnyav ions muaj kev cuam tshuam rau cov kab mob, uas yuav tsum tau muab tshem tawm ua ntej cov txheej txheem lom.Tsis tas li ntawd, qhov siab ntawm ammonia nitrogen nyob rau hauv cov dej khib nyiab kuj muaj kev cuam tshuam rau cov txheej txheem nitrification.Yog li ntawd, pretreatment yuav tsum tau ua ua ntej kev kho mob ntawm high-concentration ammonia nitrogen khib nyiab kom lub concentration ntawm ammonia nitrogen khib nyiab yog tsawg tshaj li 500mg / L.Txoj kev siv tshuaj lom neeg ib txwm yog tsim nyog rau kev kho cov dej tsis tshua muaj ammonia nitrogen cov dej khib nyiab uas muaj cov organic, xws li cov dej phwj hauv tsev, cov dej khib nyiab, thiab lwm yam.
②Simultaneous nitrification thiab denitrification (SND)
Thaum nitrification thiab denitrification tau ua ua ke hauv tib lub reactor, nws hu ua simultaneous digestion denitrification (SND).Cov pa oxygen yaj hauv cov dej khib nyiab yog txwv los ntawm tus nqi diffusion los tsim cov pa oxygen gradient hauv thaj chaw microenvironment ntawm microbial floc los yog biofilm, uas ua rau cov pa oxygen gradient nyob rau sab nrauv ntawm microbial floc lossis biofilm conducive rau kev loj hlob thiab propagation. ntawm aerobic nitrifying kab mob thiab ammoniaating kab mob.Qhov tob rau hauv floc lossis daim nyias nyias, qhov qis dua qhov concentration ntawm cov pa oxygen, ua rau thaj tsam anoxic uas cov kab mob denitrifying dominate.Yog li tsim ib txhij digestion thiab denitrification txheej txheem.Cov yam ntxwv cuam tshuam rau tib lub sijhawm zom thiab denitrification yog PH tus nqi, qhov kub thiab txias, alkalinity, organic carbon qhov chaw, yaj oxygen thiab sludge hnub nyoog.
Ib txhij nitrification / denitrification muaj nyob rau hauv Carrousel oxidation ditch, thiab cov concentration ntawm yaj oxygen ntawm lub aerated impeller nyob rau hauv lub Carrousel oxidation ditch maj mam txo, thiab cov yaj oxygen nyob rau hauv qis ntawm lub Carrousel oxidation ditch yog qis dua li nyob rau hauv sab sauv. .Kev tsim thiab noj cov nqi ntawm nitrate nitrogen nyob rau hauv txhua feem ntawm cov channel yuav luag sib npaug, thiab cov concentration ntawm ammonia nitrogen nyob rau hauv cov channel yog ib txwm tsawg heev, uas qhia tau hais tias cov nitrification thiab denitrification tshwm sim ib txhij nyob rau hauv lub Carrousel oxidation channel.
Txoj kev tshawb no ntawm kev kho cov dej phwj hauv tsev qhia tau hais tias qhov siab dua ntawm CODCr, qhov ua kom tiav qhov denitrification thiab qhov zoo dua qhov kev tshem tawm TN.Cov nyhuv ntawm yaj oxygen rau ib txhij nitrification thiab denitrification yog qhov zoo.Thaum cov pa oxygen yaj tau tswj hwm ntawm 0.5 ~ 2mg / L, tag nrho cov txiaj ntsig nitrogen tshem tawm yog qhov zoo.Nyob rau tib lub sijhawm, txoj kev nitrification thiab denitrification txuag lub reactor, luv lub sij hawm cov tshuaj tiv thaiv, muaj tsawg zog noj, txuag peev, thiab yog ib qho yooj yim kom pH tus nqi ruaj khov.
③ Kev zom zaub mov luv luv thiab denitrification
Nyob rau hauv tib lub reactor, ammonia oxidizing kab mob yog siv los oxidize ammonia rau nitrite nyob rau hauv aerobic tej yam kev mob, thiab ces nitrite yog ncaj qha denitrified los tsim nitrogen nrog organic teeb meem los yog lwm cov pa roj carbon qhov chaw raws li electron pub nyob rau hauv hypoxia.Cov feem cuam tshuam ntawm luv luv nitrification thiab denitrification yog kub, dawb ammonia, pH nqi thiab yaj oxygen.
Qhov cuam tshuam ntawm qhov kub thiab txias ntawm qhov luv luv nitrification ntawm cov dej phwj hauv nroog tsis muaj dej hiav txwv thiab cov dej phwj hauv nroog nrog 30% seawater.Cov txiaj ntsig kev sim qhia tau hais tias: rau cov dej phwj hauv nroog uas tsis muaj dej hiav txwv, qhov ntsuas kub nce ntxiv yog qhov tsim nyog rau kev ua tiav luv luv nitrification.Thaum qhov kev faib ua feem ntawm cov dej hiav txwv hauv cov dej phwj hauv tsev yog 30%, luv luv nitrification tuaj yeem ua tiav zoo dua nyob rau hauv nruab nrab qhov kub thiab txias.Delft University of Technology tsim cov txheej txheem SHARON, kev siv qhov kub thiab txias (txog 30-4090) yog qhov tsim nyog rau kev loj hlob ntawm cov kab mob nitrite, kom cov kab mob nitrite poob kev sib tw, thaum los ntawm kev tswj lub hnub nyoog ntawm cov sludge kom tshem tawm cov kab mob nitrite, yog li ntawd. tias cov tshuaj tiv thaiv nitrification nyob rau theem nitrite.
Raws li qhov sib txawv ntawm cov pa oxygen affinity ntawm cov kab mob nitrite thiab cov kab mob nitrite, Gent Microbial Ecology Laboratory tau tsim cov txheej txheem OLAND kom ua tiav cov tsub zuj zuj ntawm nitrite nitrogen los ntawm kev tswj cov pa yaj kom tshem tawm cov kab mob nitrite.
Kev sim ntsuas cov txiaj ntsig ntawm kev kho cov dej khib nyiab los ntawm luv luv nitrification thiab denitrification qhia tias thaum lub zog COD, ammonia nitrogen, TN thiab phenol concentrations yog 1201.6,510.4,540.1 thiab 110.4mg / L, qhov nruab nrab effluent COD, ammonia nitrogen. TN thiab phenol concentrations yog 197.1,14.2,181.5 thiab 0.4mg / L, feem.Cov kev tshem tawm sib raug yog 83.6%, 97.2%, 66.4% thiab 99.6%, feem.
Cov txheej txheem luv luv nitrification thiab denitrification tsis dhau mus rau theem nitrate, txuag cov pa roj carbon qhov yuav tsum tau rau kev tshem tawm cov nitrogen lom.Nws muaj qee qhov zoo rau ammonia nitrogen cov dej khib nyiab nrog qis C / N piv.Short-range nitrification thiab denitrification muaj qhov zoo ntawm cov sludge tsawg, lub sij hawm luv luv thiab txuag reactor ntim.Txawm li cas los xij, luv luv nitrification thiab denitrification yuav tsum muaj kev ruaj khov thiab kav ntev ntawm nitrite, yog li yuav ua li cas thiaj li cuam tshuam cov kev ua ntawm cov kab mob nitrifying yog qhov tseem ceeb.
④ Anaerobic ammonia oxidation
Anaerobic ammoxidation yog txheej txheem ntawm oxidation ncaj qha ntawm ammonia nitrogen rau nitrogen los ntawm cov kab mob autotrophic nyob rau hauv cov mob ntawm hypoxia, nrog nitrous nitrogen los yog nitrous nitrogen raws li electron txais.
Cov teebmeem ntawm qhov kub thiab PH ntawm kev ua haujlwm lom neeg ntawm anammoX tau kawm.Cov txiaj ntsig tau pom tias qhov ntsuas kub zoo tshaj plaws yog 30 ℃ thiab pH tus nqi yog 7.8.Kev ua tau zoo ntawm anaerobic ammoX reactor rau kev kho cov salinity siab thiab siab concentration nitrogen cov dej khib nyiab tau kawm.Cov txiaj ntsig tau pom tias muaj salinity siab inhibited anammoX kev ua, thiab qhov inhibition yog thim rov qab.Cov kev ua anaerobic ammox ntawm cov sludge unaaclimated yog 67.5% qis dua li ntawm cov tswj sludge nyob rau hauv lub salinity ntawm 30g.L-1 (NaC1).Qhov kev ua ntawm anammoX ntawm cov sludge acclimated yog 45.1% qis dua qhov kev tswj hwm.Thaum lub acclimated sludge raug xa mus los ntawm qhov chaw siab salinity mus rau qhov chaw qis salinity (tsis muaj brine), qhov kev ua anaerobic ammoX tau nce los ntawm 43.1%.Txawm li cas los xij, lub reactor yog nquag ua haujlwm poob thaum nws khiav hauv siab salinity ntev.
Piv nrog rau cov txheej txheem lom neeg ib txwm muaj, anaerobic ammoX yog ib qho kev lag luam roj ntsha nitrogen tshem tawm tshuab tsis muaj cov pa roj carbon ntxiv, tsis muaj oxygen xav tau, tsis xav tau cov tshuaj reagents rau neutralize, thiab tsawg sludge ntau lawm.Qhov tsis zoo ntawm anaerobic ammox yog tias cov tshuaj tiv thaiv ceev qeeb, lub reactor ntim loj, thiab cov pa roj carbon monoxide tsis zoo rau anaerobic amMOX, uas muaj qhov tseem ceeb rau kev daws cov dej ammonia nitrogen uas tsis zoo biodegradability.
4.Kev sib cais thiab adsorption nitrogen tshem tawm cov txheej txheem
① txoj kev sib cais membrane
Membrane cais txoj kev yog siv cov kev xaiv permeability ntawm daim nyias nyias los xaiv cais cov Cheebtsam hauv cov kua, thiaj li ua tiav lub hom phiaj ntawm ammonia nitrogen tshem tawm.Xws li rov qab osmosis, nanofiltration, deammoniating membrane thiab electrodialysis.Cov yam ntxwv cuam tshuam rau kev sib cais ntawm daim nyias nyias yog cov yam ntxwv ntawm daim nyias nyias, lub siab lossis qhov voltage, pH tus nqi, qhov kub thiab txias thiab ammonia nitrogen concentration.
Raws li cov dej zoo ntawm ammonia nitrogen cov dej khib nyiab tawm los ntawm lub ntiaj teb tsis tshua muaj smelter, qhov kev sim rov qab osmosis tau ua nrog NH4C1 thiab NaCI simulated dej khib nyiab.Nws tau pom tias nyob rau hauv tib lub sijhawm, rov qab osmosis muaj qhov tshem tawm ntau dua ntawm NaCI, thaum NHCl muaj cov dej ntau dua.Kev tshem tawm tus nqi ntawm NH4C1 yog 77.3% tom qab kev kho rov qab osmosis, uas tuaj yeem siv los ua kev kho ntawm ammonia nitrogen cov dej khib nyiab.Rov qab osmosis thev naus laus zis tuaj yeem txuag lub zog, zoo thermal stability, tab sis cov tshuaj chlorine tsis kam, cov pa phem tsis zoo.
Cov txheej txheem biochemical nanofiltration membrane sib cais tau siv los kho cov khib nyiab pov tseg, kom 85% ~ 90% ntawm cov kua permeable raug tso tawm raws li tus qauv, thiab tsuas yog 0% ~ 15% ntawm cov kua dej phwj tuaj thiab cov av nkos tau xa rov qab mus rau qhov qub. khib nyiab tank.Ozturki et al.kho cov khib nyiab pov tseg ntawm Odayeri hauv Qaib Cov Txwv nrog nanofiltration membrane, thiab tshem tawm tus nqi ntawm ammonia nitrogen yog li ntawm 72%.Nanofiltration membrane yuav tsum qis dua qhov rov qab osmosis membrane, yooj yim rau kev khiav lag luam.
Lub ammonia-tshem cov membrane feem ntau yog siv rau hauv kev kho cov dej khib nyiab nrog siab ammonia nitrogen.Cov ammonia nitrogen hauv dej muaj qhov sib npaug hauv qab no: NH4- + OH-= NH3 + H2O hauv kev ua haujlwm, cov dej khib nyiab uas muaj ammonia ntws hauv lub plhaub ntawm daim nyias nyias, thiab cov kua qaub-absorbing hauv cov yeeb nkab ntawm daim nyias nyias. module.Thaum PH ntawm cov dej khib nyiab nce los yog qhov kub thiab txias, qhov sib npaug yuav hloov mus rau sab xis, thiab ammonium ion NH4- dhau los ua cov pa roj dawb NH3.Lub sijhawm no, gaseous NH3 tuaj yeem nkag mus rau theem acid nqus cov kua hauv cov yeeb nkab los ntawm cov dej khib nyiab hauv lub plhaub los ntawm cov micropores ntawm cov hollow fiber, uas yog absorbed los ntawm cov kua qaub thiab tam sim ntawd ua ionic NH4-.Khaws cov PH ntawm cov dej khib nyiab siab tshaj 10, thiab qhov kub siab tshaj 35 ° C (qis dua 50 ° C), kom NH4 nyob rau hauv cov dej khib nyiab yuav tsis tu ncua ua NH3 mus rau qhov nqus kua theem tsiv teb tsaws.Yog li ntawd, qhov concentration ntawm ammonia nitrogen nyob rau hauv cov dej khib nyiab poob tsis tu ncua.Cov kua qaub nqus dej theem, vim tias tsuas yog cov kua qaub thiab NH4-, tsim cov ntsev ammonium ntshiab heev, thiab ncav cuag ib qho kev xav tau tom qab kev mus tas li, uas tuaj yeem rov ua dua.Ntawm qhov tod tes, kev siv cov thev naus laus zis no tuaj yeem txhim kho qhov kev tshem tawm ntawm ammonia nitrogen hauv cov dej khib nyiab, thiab ntawm qhov tod tes, nws tuaj yeem txo tag nrho cov nqi khiav lag luam ntawm cov dej khib nyiab.
② txoj kev electrodialysis
Electrodialysis yog ib txoj hauv kev tshem tawm cov khoom tawg ntawm cov dej hauv cov dej los ntawm kev siv cov hluav taws xob ntawm cov khoom sib txuas.Nyob rau hauv qhov kev txiav txim ntawm qhov hluav taws xob, cov ammonia ions thiab lwm yam ions nyob rau hauv ammonia-nitrogen khib nyiab yog enriched los ntawm daim nyias nyias nyob rau hauv cov ammonia-muaj concentrated dej, thiaj li mus cuag lub hom phiaj ntawm kev tshem tawm.
Cov txheej txheem electrodialysis tau siv los kho cov dej khib nyiab tsis muaj zog nrog cov ntsiab lus siab ntawm ammonia nitrogen thiab ua tiav cov txiaj ntsig zoo.Rau 2000-3000mg / L ammonia nitrogen cov dej khib nyiab, qhov kev tshem tawm ntawm ammonia nitrogen tuaj yeem ntau dua 85%, thiab cov dej ammonia concentrated tuaj yeem tau los ntawm 8.9%.Tus nqi hluav taws xob siv thaum lub sijhawm ua haujlwm ntawm electrodialysis yog proportional rau tus nqi ntawm ammonia nitrogen hauv cov dej khib nyiab.Electrodialysis kev kho cov dej khib nyiab tsis txwv los ntawm tus nqi pH, qhov kub thiab txias, thiab nws yooj yim rau kev khiav lag luam.
Qhov zoo ntawm kev sib cais ntawm daim nyias nyias yog siab rov qab ntawm ammonia nitrogen, kev ua haujlwm yooj yim, kev kho mob ruaj khov thiab tsis muaj kuab paug thib ob.Txawm li cas los xij, nyob rau hauv kev kho mob ntawm high-concentration ammonia nitrogen cov dej khib nyiab, tshwj tsis yog rau cov deammoniated membrane, lwm cov membranes yooj yim rau scale thiab clog, thiab regeneration thiab backwashing yog nquag, nce nqi kho.Yog li ntawd, txoj kev no yog tsim nyog rau pretreatment los yog tsawg-concentration ammonia nitrogen khib nyiab.
③ Ion pauv txoj kev
Ion txauv txoj kev yog ib txoj hauv kev los tshem tawm ammonia nitrogen los ntawm cov dej khib nyiab los ntawm kev siv cov ntaub ntawv uas muaj zog xaiv adsorption ntawm ammonia ions.Cov khoom siv adsorption feem ntau yog activated carbon, zeolite, montmorillonite thiab pauv resin.Zeolite yog ib hom silico-aluminate nrog peb-dimensional spatial qauv, tsis tu ncua pore qauv thiab qhov, ntawm cov uas clinoptilolite muaj ib tug muaj zog xaiv adsorption muaj peev xwm rau ammonia ions thiab tsis tshua muaj nqi, yog li nws yog feem ntau siv raws li ib tug adsorption khoom rau ammonia nitrogen khib nyiab. hauv engineering.Cov yam ntxwv cuam tshuam rau kev kho mob ntawm clinoptilolite muaj xws li particle loj, influent ammonia nitrogen concentration, tiv tauj lub sij hawm, pH nqi thiab lwm yam.
Cov nyhuv adsorption ntawm zeolite ntawm ammonia nitrogen yog pom tseeb, ua raws li ranite, thiab cov nyhuv ntawm cov av thiab ceramisite tsis zoo.Txoj hauv kev tseem ceeb kom tshem tawm ammonia nitrogen los ntawm zeolite yog ion txauv, thiab cov nyhuv adsorption ntawm lub cev me me heev.Cov ion pauv nyhuv ntawm ceramite, av thiab ranite zoo ib yam li cov nyhuv adsorption lub cev.Lub peev xwm adsorption ntawm plaub lub fillers poob nrog qhov nce ntawm qhov kub thiab txias hauv thaj tsam ntawm 15-35 ℃, thiab nce nrog qhov nce ntawm pH tus nqi hauv thaj tsam ntawm 3-9.Lub adsorption equilibrium tau mus txog tom qab 6h oscillation.
Qhov ua tau ntawm kev tshem tawm ammonia nitrogen los ntawm cov av hauv av los ntawm zeolite adsorption tau kawm.Cov txiaj ntsig kev sim qhia tau hais tias txhua gram ntawm zeolite muaj qhov txwv tsis pub muaj peev xwm ntawm 15.5mg ammonia nitrogen, thaum zeolite particle loj yog 30-16 mesh, qhov kev tshem tawm ntawm ammonia nitrogen nce mus txog 78.5%, thiab nyob rau tib lub sijhawm adsorption, ntau npaum li cas thiab zeolite particle loj, qhov siab dua qhov muaj zog ammonia nitrogen concentration, siab dua tus nqi adsorption, thiab nws muaj peev xwm ua tau rau zeolite li adsorbent kom tshem tawm ammonia nitrogen los ntawm leachate.Nyob rau tib lub sijhawm, nws tau taw qhia tias qhov adsorption tus nqi ntawm ammonia nitrogen los ntawm zeolite yog qhov tsawg, thiab nws yog qhov nyuaj rau zeolite kom ncav cuag lub peev xwm saturation adsorption hauv kev ua haujlwm.
Kev tshem tawm cov nyhuv ntawm cov pa roj ntsha zeolite ntawm nitrogen, COD thiab lwm cov pa phem hauv cov dej phwj hauv simulated hauv zos tau kawm.Cov txiaj ntsig tau pom tias qhov kev tshem tawm ntawm ammonia nitrogen los ntawm bio zeolite txaj yog ntau tshaj 95%, thiab kev tshem tawm ntawm nitrate nitrogen cuam tshuam zoo heev los ntawm lub sijhawm hydraulic nyob.
Txoj kev sib pauv ion muaj qhov zoo ntawm kev nqis peev me me, txheej txheem yooj yim, kev ua haujlwm yooj yim, tsis muaj tshuaj lom thiab kub, thiab rov siv cov zeolite los ntawm kev tsim dua tshiab.Txawm li cas los xij, thaum kho cov dej khib nyiab siab ammonia nitrogen, qhov rov tsim dua yog nquag, uas ua rau tsis yooj yim rau kev ua haujlwm, yog li nws yuav tsum tau ua ke nrog lwm txoj kev kho ammonia nitrogen, los yog siv los kho cov dej tsis tshua muaj ammonia nitrogen.
Lag luam wholesale 4A Zeolite Chaw tsim tshuaj paus thiab tsum |EVERBRIGHT (cnchemist.com)
Post lub sij hawm: Lub Xya hli ntuj-10-2024
