Txhim kho microbial kho ntawm qej khib nyiab siv MBBR + A / O txheej txheem
Txheej txheem cej luam
Qej khib nyiabFeem ntau yog los ntawm kev txiav thiab yaug cov txheej txheem thaum lub sij hawm ua qej. Nws yog characterized los ntawmhigh concentrations ntawm organic teeb meem, sCov qib tsis tseem ceeb ntawm nitrogen thiab phosphorus, thiab muaj ntau ntau ntawm allicin. Allicin (diallyl thiosulfinate) yog cov kua tsis hloov pauv lub luag haujlwm rau pungent tsw ntawm qej thiab yog tshuaj tsis ruaj khov thiab muaj zog heev. Allicin tuaj yeem cuam tshuam kev loj hlob ntawm ntau yam kab mob. Kev tso tawm siab -kev ua kom muaj zog qej cov dej khib nyiab yam tsis muaj kev kho mob ua rau muaj kev cuam tshuam loj rau ib puag ncig. Qee cov kws tshawb fawb tau siv cov txheej txheem xws li kev lim dej, Fenton oxidation, thiab micro-electrolysis, tab sis cov txheej txheem no tsis zoo rau kev kho cov dej khib nyiab, thiab kev siv tshuaj ntau ntau ua rau cov nqi kho mob tom ntej. Ntau tus kws tshawb fawb tau tawm tswv yim txog kev kho mob lom neeg siv cov txheej txheem anaerobic-aerobic ua ke. Txawm li cas los xij, vim muaj cov kab mob tua kab mob ntawm allicin, cov kab mob tsis yooj yim rau kev cog qoob loo, thiab kev kho mob tsis zoo. Yog li ntawd, lub hom phiaj ntawm kev kho mob lom yog muscultivate thiab acclimatize microbial hom muaj peev xwm hloov mus rau qej khib nyiab thiab txhim kho lawv cov biodegradation.
Qhov kev tshawb fawb no suav nrog kev cog qoob loo thiab tshuaj xyuasCov kab mob muaj txiaj ntsig zoo hauv kev degrading qej cov dej khib nyiab, uas tau muab coj los rau hauv aTsiv txaj Biofilm Reactor (MBBR). Siv inoculated sludge thiab ib tug khiav - tus nqi nce biofilm txoj kev tsim, biofilms tau tsim los txhim kho kev tshem tawm nitrogen thiab phosphorus los ntawm cov dej khib nyiab. Qhov no tau ua raws li A / O (Anoxic / Oxic) biochemical kho ntxiv. Raws li GB18918-2002 tus qauv, COD effluent COD thiab Ammonia Nitrogen (NH₃-}N) qib tuaj yeem ua tau raws li tus qauv thib ob (COD: 100 mg/L, NH₃-N: 25-30 mg/L). Cov txheej txheem no zoo txo cov ntsiab lus ntawm cov organic hauv cov dej ntws, txo qhov nyuaj ntawm cov theem tom ntej.
1. Ntu kev sim
1.1 Txheej Txheem Flow Design
Tag nrho cov txheej txheem ntws rau qej khib nyiab kho yog qhia hauvDaim duab 1, nrog lub ntsiab tivthaiv yog lubBiodegradation hauv MBBR + A / O system. Peb cov tshuaj ntsuam xyuas thiab cais tawm muaj txiaj ntsig zoo hauv kev degrading qej cov dej khib nyiab - Alcaligenes sp., Acinetobacter sp., thiab Achromobacter sp. - tau tov nrog cov activated sludge thiab nkag mus rau hauv MBBR chav tsev kom yooj yim rau nws pib sai- nce.
1.2 MBBR + A/O Kev Kho Mob
Tom qab dhau los ntawm ntxhib thiab zoo cov ntxaij vab tshaus kom tshem tawm cov khib nyiab, qej cov dej khib nyiab yog tso ncaj qha rau hauv MBBR. Lub influent zoo yog qhia nyob rau hauvTable 1. Cov dej ntws los ntawm MBBR ntws ncaj qha rau hauv A / O system. Vim muaj cov ntsiab lus organic tsawg ntawm MBBR effluent, raw qej khib nyiab yog tsim nyog ntxiv rau lub tank Oxic (O) los ntxiv cov pa roj carbon rau cov txheej txheem A / O. Txhawm rau ntsuas qhov kev cuam tshuam ntawm cov kab ke, cov organic loading tus nqi ntawm MBBR tau maj mam nce thaum lub sijhawm ua haujlwm tas mus li, thiab cov dej ntws zoo tau raug saib xyuas.
1.3 Txheej txheem Parameter
1.3.1 Dissolved Oxygen (DO)
Ntau dhau DO nyob rau hauv biofilm tuaj yeem tiv thaiv denitrification, ua rau MBBR poob nws ib txhij nitrification thiab denitrification muaj peev xwm. Tsis tshua muaj DO tuaj yeem ua rau kev loj hlob ntawm cov kab mob filamentous, cuam tshuam rau cov dej ntws zoo thiab inhibiting cov txheej txheem nitrification.
1.3.2 Hydraulic Retention Time (HRT)
Ib qho luv luv HRT ua rau mob hnyav heev, qhov twg cov dej khib nyiab uas muaj cov organic feem ntau raug tso tawm ua ntej yuav nqus tag nrho. Nruam inflow ua kom cov kab mob nyob rau hauv ib qho chaw tas li ntawm biodegradation, txo efficiency thiab nce zog noj. HRT ntev ntev ua rau kom cov as-ham tsis txaus; Tsis muaj cov as-ham, microorganisms txo lawv cov kev ua haujlwm thiab kev xav tau ntawm cov metabolism hauv tsuas yog ua kom muaj sia nyob.
1.3.3 Carbon-rau-Nitrogen Ratio (C/N)
Qhov qis C / N piv tuaj yeem ua rau catalysis ntawm ammonia hloov mus rau lwm yam tshuaj, cuam tshuam rau ammonia nitrogen tshem tawm. Nws kuj yooj yim ua rau filamentous bulking, tsis tu ncua kev loj hlob cuam tshuam flocculation, ua rau sludge bulking thiab ntab sludge. Qhov siab C / N piv tsis zoo rau microbial biodegradation thiab kev loj hlob, ua rau cov organic load ntawm cov kab mob.
1.4 MBBR Biofilm Pib-up
Biofilm Pib-up: Cov inoculated sludge + flow- tus nqi nce txoj kev tau siv. MBR-enriched activated sludge yog inoculated rau hauv lub reactor, nrog thawj zaug Mixed Liquor Suspended Solids (MLSS) concentration ntawm kwv yees li 5.82 g / L. Aeration tau pib, thiab cov cab kuj polyethylene tau ntxiv rau lub reactor nrog afilling ratio ntawm li 60%. CovDOnyob rau hauv lub reactor tau tswjntau dua 4.0 mg / L. Cov dej ntws ntws tau nce zuj zus hauv 20 L / h increments: 20, 40, 60, 80, 100, 120, 140 L / h, nrog rau txhua qhov dej ntws tau khaws cia rau 1 hnub. Tsis muaj sludge tau nkim thaum lub sijhawm no. Lub teeb daj biofilm tsim nyob rau saum npoo ntawm cov neeg nqa khoom uas cov kab mob txuas nrog thiab loj hlob. Tom qab ua tiav biofilm pib- nce, kev ua haujlwm ruaj khov txuas ntxiv, tuav ib qhoSludge Retention Time (SRT) ntawm 30 hnub. Thaum lub sijhawm ua haujlwm ruaj khov, tus nqi thauj khoom organic ntawm MBBR tau hloov kho kom pom nws qhov cuam tshuam ntawm COD, nitrogen, thiab phosphorus tshem tawm.
2. Cov txiaj ntsig thiab kev sib tham
2.1 Kev soj ntsuam ntawm MBBR Effluent Quality Thaum Biofilm Pib-up
Qhov kev siv aeration hauv MBBR tau hloov kho los tswj DO concentration. Thaum DO yog qis dua 4.0 mg / L, qhov kev siv aeration tsis txaus los txhawb kev sib txuam, siab - ntws turbulent txav ntawm cov cab kuj, tiv thaiv kev sib xyaw kom txaus thiab ua rau nws nyuaj rau tsim cov biofilm ntawm cov khoom nqa khoom. Thaum DO nyob nruab nrab ntawm 4.0-6.0 mg / L, cov neeg nqa khoom sib xyaw kom zoo nrog cov activated sludge thiab dej khib nyiab. Kev hloov xim los ntawm dawb mus rau yellowish- xim av ntawm cov cab kuj tau pom, qhia tau hais tias muaj kev vam meej microbial txuas thiab kev loj hlob nyob rau hauv qhov kev siv aeration no, raws li qhia hauvDaim duab 2.
Qhov kev hloov pauv ntawm qhov muaj txiaj ntsig thiab cov dej ntws tawm COD thaum pib- theem nce yog qhia hauvDaim duab 3(a). Thawj qhov kev txo qis hauv kev kho mob yog vim qhov tsawg heev ntawm cov kab mob sib txuas ntawm cov cab; Lub degradation los ntawm cov kab mob nyob rau hauv lub activated sludge ib leeg yog tsis txaus kom tshem tawm cov loj npaum li cas ntawm cov organics. Raws li qhov pib- nce zuj zus, tus nqi ntawm cov kab mob sib txuas ntawm cov neeg nqa khoom tau nce ntxiv, maj mam ua ib qho biofilm. Lub effluent COD concentration maj stabilized, thiab COD tshem tawm efficiency stabilized saum 90%.
Qhov kev hloov pauv ntawm MBBR influent thiab effluent NH₃-N tau qhia hauvDaim duab 3 (b). Lub nitrification los ntawm cov kab mob aerobic nyob rau hauv lub activated sludge zoo tshem tawm ammonia nitrogen. Pib txij hnub 7, NH₃-N cov concentration maj mam nce. Txog hnub 23, txawm hais tias tus muaj hwj chim NH₃-N tseem nce ntxiv, tus nqi tshem tawm kuj nce ntxiv. Qhov no yog vim nitrifying kab mob loj hlob maj mam pib; Nrog rau lub sijhawm, lawv cov pejxeem tau nce, biofilm matured, thiab NH₃-N tshem tawm tus nqi maj mam nce thiab ruaj khov.
Qhov sib txawv nkhaus ntawm MBBR influent thiab effluent TN yog qhia hauvDaim duab 3 (c). Tsis zoo li ammonia nitrogen tshem tawm, TN tshem tawm efficiency poob pib. Qhov no yog vim qhov chaw reactor muaj cov pa oxygen thiab cov pa roj carbon ntau, txwv kev loj hlob ntawm cov kab mob denitrifying. Txawm li cas los xij, raws li biofilm tsim, TN tshem tawm efficiency pib txhim kho. Txog hnub tim 20, txawm hais tias qhov muaj txiaj ntsig TN concentration nce ntxiv, cov dej ntws tawm TN thiab kev tshem tawm tau ruaj khov, nyob nruab nrab ntawm 50% -60%.
Qhov sib txawv nkhaus ntawm MBBR influent thiab effluent TP yog qhia hauvDaim duab 3(d). Txij thaum pib- mus txog rau kev ua haujlwm ruaj khov, tus nqi tshem tawm TP tseem nyob ruaj khov. Txawm hais tias qhov muaj zog TP concentration yog siab pib thiab txo qis tom qab, qhov kev tshem tawm tau pom tsis muaj kev hloov pauv tseem ceeb, qhia txog lub peev xwm ntawm kev tshem tawm phosphorus. TP tshem tawm tus nqi nyob rau hauv lub kaw lus tau tswj ntawm 80% -90%.
Hauv cov ntsiab lus,tswj qhov MBBR system DO ntawm 4–6 mg / L, ib tug paub tab biofilm tsim tom qab 20 hnub ntawm kev pub noj tsis tu ncua. Piv nrog rau cov txheej txheem activated sludge ib txwm muaj, MBBR system muaj kev cuam tshuam muaj zog thiab kev kho mob siab, txo qhov nyuaj ntawm kev kho cov theem tom ntej rau qej ua cov dej khib nyiab.
2.2 Kev Ntsuam Xyuas Kev Ua Haujlwm Zoo Thaum Lub Sijhawm Ua Haujlwm
Tom qab biofilm pib- theem, biofilm matured. Txhawm rau kuaj qhov cuam tshuam tsis zoo ntawm MBBR system, cov organic loading tus nqi tau nce ntxiv thaum lub sijhawm ua haujlwm ruaj khov.
Qhov kev hloov pauv ntawm MBBR influent thiab effluent COD thaum lub sijhawm ua haujlwm ruaj khov yog qhia hauvDaim duab 4(a). Txij hnub 1-5, nrog kev nkag mus tas li, COD tshem tawm cov txiaj ntsig tseem nyob siab dua 95%, thiab cov dej COD cov ntsiab lus tau nce mus txog 100 mg / L. Los ntawm hnub 5-20, tus nqi nkag tau nce, maj mam nce cov organic loading ntawm 20 kgCOD / m³·d rau 30 kgCOD / m³·d. Tsis muaj kev hloov pauv tseem ceeb hauv kev tshem tawm tau pom zoo, thiab cov dej COD tseem nyob nruab nrab ntawm 80-100 mg / L, ua rau pom muaj zog tiv thaiv. Tom qab hnub 20, tus nqi nkag tau nce ntxiv, tsis tu ncua nce cov organic loading hauv reactor los ntawm 30 kgCOD / m³·d rau 37 kgCOD / m³·d, khaws cia rau 5 hnub. MBBR lub peev xwm tshem tawm COD tseem nyob siab dua 95%.
Cov duab 4(b) thiab (c)qhia qhov sib txawv nkhaus rau NH₃-N thiab TN, raws li, thaum lub sijhawm ua haujlwm ruaj khov. Txij hnub 1-5, nrog kev nkag mus tas li, MBBR biofilm tau nthuav tawm ib txhij nitrification thiab denitrification. Aerobic nitrifying kab mob txuas mus rau txheej txheej ntawm biofilm, tag nrho tov nrog cov dej khib nyiab hauv qab aeration, noj cov nitrogen tseem ceeb los ntawm nitrification. Denitrifying kab mob nyob rau hauv lub puab anoxic txheej zoo tshem tawm nitrate nitrogen los ntawm denitrification. Txij hnub 5-20, raws li tus nqi nkag tau nce, qhov kev tshem tawm ntawm NH₃-N thiab TN pib poob qis heev. Tom qab li 7 hnub ntawm kev ua haujlwm tas mus li, lub kaw lus maj mam hloov. Txawm hais tias qhov kev tshem tawm tau zoo rau NH₃-N thiab TN tom qab ntawd nce, nws tseem qis dua thaum lub sijhawm qis - ntws. Raws li kev nkag mus tas li, NH₃-N tshem tawm mus txog ntau dua 90%, nrog cov dej ntws NH₃-N nruab nrab ntawm 10-15 mg / L, thiab TN tshem tawm yog qhov tseem ceeb khaws cia siab dua 80%, nrog cov dej TN nyob ib ncig ntawm 30 mg / L. Tom qab nce cov dej ntws thiab lub cev mus txog qhov sib npaug tshiab raws li qhov cuam tshuam tas mus li, NH₃{24}}N tshem tawm ruaj khov nyob ib puag ncig 80%, nrog cov dej ntws NH₃-N ntawm 50-70 mg / L, thiab TN tshem tawm ib ncig ntawm 60%, nrog TN cov dej hauv qab 50 mg / L.
Qhov kev hloov pauv rau TP thaum lub sijhawm ua haujlwm ruaj khov yog qhia hauvDaim duab 4(d). Qhov TP concentration ntawm effluent yog nyob ib ncig ntawm 10 mg / L. Thaum xub thawj, nrog qhov qis qis thiab qis qis TP concentration, cov nyhuv kho tau txwv. Raws li tus nqi nkag thiab muaj zog TP concentration nce, kev kho mob siab tau ua tiav thoob plaws theem cuam tshuam thiab kev ua haujlwm siab tom ntej, nrog rau TP tshem tawm tus nqi hloov pauv ntawm 90%.
Hauv cov ntsiab lus,Raws li cov organic loading poob siab, lub kaw lus COD tshem tawm efficiency tseem tsis tau hloov pauv, tab sis kev tshem tawm ntawm NH₃-N thiab TN txo qis dua.. Thaum cov organic loading mus txog nws qhov siab tshaj plaws ntawm 37 kgCOD / m³·d, lub kaw lus tshem tawm kev ua haujlwm rau NH₃-N thiab TN poob qis.
2.3 Kev Ntsuam Xyuas Qhov Zoo ntawm MBBR + A/O System
Tom qab biofilm pib- theem nce thiab ib lub hlis ntawm kev ua haujlwm ruaj khov, cov txheej txheem A/O tau muab tso rau hauv qab rau kev kho mob siab heev ntawm MBBR effluent. Gradient nce nyob rau hauv tus nqi inflow yog siv los ua kom tag nrho cov organic loading, aiming los txiav txim qhov zoo tshaj plaws inflow tus nqi, sib xws rau qhov zoo HRT.
COD variation nkhaus yog qhia hauvDaim duab 5 (a). Tus nqi nkag tau nce ntxiv: 100, 120, 130, 150, 170 L / h. Los ntawm qhov pib mus rau qhov siab tshaj plaws ntws, cov organic loading ntawm MBBR system tau nce los ntawm 20 kgCOD / m³·d rau 37 kgCOD / m³·d. Qhov kawg effluent los ntawm kev sib xyaw ua ke tseem nyob ruaj khov, nrog COD concentration qis dua 100 mg / L. Raws li kev txhawb nqa siab ntawm cov organic loading poob siab, MBBR system ua tau zoo, txawm hais tias nws cov dej ntws COD tau pom qhov nce me ntsis thaum tus nqi ntws mus txog 150 L / h. Tom qab tswj hwm qhov 170 L / h ntws tus nqi rau ob peb hnub, qhov pom kev nce siab hauv MBBR effluent COD tau pom. Txawm li cas los xij, nrog rau cov txheej txheem A / O tom ntej, qhov kawg ua ke cov dej ntws tawm tseem khaws cia qis dua 100 mg / L. Qhov no qhia tau hais tias txawm tias nyob rau hauv qhov siab ntawm cov organic loading poob siab ntawm 37 kgCOD / m³·d, cov txheej txheem ua ke tseem muaj zog tshem tawm ntawm qej ua cov dej khib nyiab.
Cov kev hloov pauv rau NH₃-N thiab TN tau qhia hauvCov duab 5(b) thiab (c), raws. Qej ua cov dej khib nyiab muaj qhov siab ntawm ammonia nitrogen thiab tag nrho cov nitrogen, uas tuaj yeem nce ntxiv rau lub sijhawm vim oxidation. Feem ntau, ammonia nitrogen concentration yog li ntawm 300-500 mg / L, thiab tag nrho nitrogen los ntawm 450-600 mg / L. Nyob rau hauv ib txhij nitrification thiab denitrification nyob rau hauv MBBR, ammonia nitrogen tshem tawm tau zoo dua, tej zaum vim hais tias nitrifying kab mob siv cov dej khib nyiab zoo dua nyob rau hauv aeration. Cov kab mob denitrifying yuav tsum muaj cov kab mob anoxic thiab feem ntau yog nyob ntawm kev noj cov organic carbon rau denitrification. Thaum nce tus nqi nkag, qhov kev tshem tawm ntawm NH₃-N thiab TN yog thawj qhov kev txiav txim siab. Txij hnub tim 1–4, vim qhov qis qis thiab nruab nrab NH₃-N, NH₃-N tshem tawm tus nqi tseem nyob siab dua 90%, thiab TN tshem tawm efficiency maj mam nce. Tom qab ntawd, tus nqi nkag tau nce ntxiv. Nws tau pom meej meej tias raws li tus nqi nkag tau nce ntxiv, cov dej ntws tawm ntawm NH₃-N thiab TN ntawm cov theem sib txawv tau nce zuj zus, nrog cov nqi nkag siab dua ua rau muaj cov dej ntws ntau dua. Raws li tus nqi ntws nce, biomass ntawm cov khoom siv biofilm tau nce ntxiv, txhim kho nitrification, qhov twg ammonia nitrogen yog oxidized los ntawm nitrifying kab mob rau nitrate thiab nitrite nyob rau hauv oxygen.
TP concentration variation nkhaus yog qhia nyob rau hauvDaim duab 5(d). Muab qhov muaj zog COD thiab TN concentrations, qhov theoretical pom TP concentration rau microbial kev loj hlob yog siab dua 100 mg / L. Txawm li cas los xij, qhov muaj txiaj ntsig TP concentration tau qis dua qhov kev xav tau no. Yog li ntawd, MBBR effluent TP concentration tseem nyob ib ncig ntawm 10 mg / L, thiab qhov kawg sib xyaw ua ke TP concentration tau khaws cia ntawm 2-3 mg / L.
Cov yam ntxwv sludge ntawm MBBR system thiab tom ntej A / O system ua ntej thiab tom qab ua haujlwm tau ntsuas, raws li qhia hauvRooj 2.
Hauv cov ntsiab lus,Thaum tus nqi ntws tau nce mus rau 150 L / h, cov nqi tshem tawm rau COD, NH₃-N, TN, thiab TP tau zoo dua li ntawm lwm cov nqi ntws. HRT ntawm tus nqi ntws no yog 27 teev. Tsis tas li ntawd, cov sludge concentration nyob rau hauv ob qho tib si MBBR thiab A / O systems tau nce ntau tom qab ua haujlwm.
3. Cov lus xaus
Tom qab tsim biofilm hauv MBBR, qhov kev tshem tawm tau zoo rau COD, NH₃-N, TN, thiab TP tau ruaj khov. Lub sijhawm ib hlis ntawm kev ua haujlwm tas mus li nyob rau hauv cov xwm txheej ruaj khov, COD tshem tawm mus txog ntau dua 95%, NH₃-N thiab TN tshem tawm tau ruaj khov nyob ib puag ncig 80%, thiab TP tshem tawm tau ruaj khov nyob ib puag ncig 90%.
MBBR effluent tau kho ntxiv hauv A/O system. Cov txheej txheem ua ke tuaj yeem tiv taus cov khoom thauj mus txog 37 kgCOD / m³·d. Kev ua haujlwm zoo tshaj plaws rau tag nrho cov txheej txheem yog nyob rau hauv HRT ntawm 27 teev. Qhov kawg effluent COD stabilized qis dua 100 mg/L, NH₃-N ntawm 10–20 mg/L, TN qis dua 30 mg/L, thiab TP hauv qab 10 mg/L. Cov sludge concentration nyob rau hauv MBBR system tom qab ua hauj lwm yog 8.5 g / L, thiab nyob rau hauv lub A / O system yog 4.1 g / L, ob qho tib si ho siab dua ua ntej ua hauj lwm, qhia tau hais tias ib tug ntau ntawm cov microbial biomass. COD thiab ammonia nitrogen theem tom qab kev kho mob lom tau ua tau raws li tus qauv tso tawm thib ob ntawm GB18918-2002. Rau kev kho mob ntxiv, Fenton's advanced oxidation thev naus laus zis tuaj yeem ua haujlwm rau kev kho mob sib sib zog nqus ntawm cov khoom siv tshuaj lom neeg kom ua tiav cov qauv tso tawm thawj zaug.