Kev soj ntsuam ntawm qhov cuam tshuam ntawm MBBR txheej txheem Retrofit hauv Southern Wastewater Treatment Plant
Daim ntawv tshaj tawm "2022 Tuam Tshoj Urban Construction Status Bulletin" tso tawm los ntawm Ministry of Housing and Urban-Rural Development of the People's Republic of China thaum Lub Kaum Hli 2023 qhia tau hais tias thaum kawg ntawm 2022, lub peev xwm kho cov dej khib nyiab hauv Suav teb tau nce mus txog 216 lab m³ / d, ib xyoos - nce 4% ntawm {6}. Tag nrho cov ntim ntawm cov dej khib nyiab kho tau nyob rau hauv txoj kev loj hlob rau 10 xyoo sib law liag txij li xyoo 2013. Txoj kev loj hlob sai ntawm cov nroog yog nrog kev nce hauv cov dej khib nyiab, thiab qhov tsis sib xws ntawm thaj av xav tau rau kev nthuav dav thiab kev kho dua tshiab ntawm cov chaw kho dej khib nyiab thiab thaj av loj hlob hauv nroog tau dhau los ua qhov tseem ceeb.
Rau kev nthuav dav lub peev xwm ntawm cov chaw kho dej khib nyiab uas twb muaj lawm, cov txheej txheem ua kom cov sludge feem ntau siv cov txheej txheem ntawm kev cog qoob loo. Raws li kev nthuav dav ntxiv, cov nqi av yuav maj mam nce, thiab lub sijhawm tsim kho txuas ntxiv. Kev sib sib zog nqus ntawm tapping lub peev xwm kho nyob rau hauv cov chaw kho dej khib nyiab uas twb muaj lawm tam sim no yog ib qho kev ntsuas zoo los txhim kho kev kho dej khib nyiab hauv nroog thiab txo qhov tsis sib xws ntawm kev tsim kho hauv nroog thiab kev siv av. Lub Moving Bed Biofilm Reactor (MBBR) tau tshwm sim hauv Norway thaum xyoo 1980s. Nws txhim kho cov kab mob ua kom muaj txiaj ntsig zoo thiab yog li txhim kho cov kab ke kev kho mob uas muaj peev xwm los ntawm kev ntxiv cov cab cab mus rau hauv lub tank los tsim cov biofilms. Vim nws cov yam ntxwv ntawm kev muaj peev xwm "kho" rau hauv lub hauv paus kev lom neeg, nws yog dav siv nyob rau hauv kev kho dua tshiab thiab kho dua tshiab ntawm cov dej khib nyiab kho cov nroj tsuag, ua tiav hauv -situ muaj peev xwm txhim kho yam tsis tau ntxiv av tshiab. Tsis tas li ntawd, piv rau lwm thaj av- txuag cov txheej txheem retrofit xws li Membrane Bioreactor (MBR) thiab High Concentration Composite Powder Carrier Biological Fluidized Bed (HPB), cov txheej txheem MBBR tsis tas yuav hloov lub sij hawm los yog ntxiv cov khoom thauj, ua rau nws muaj txiaj ntsig zoo rau kev lag luam.
Kab lus no siv lub peev xwm nthuav dav rov qab siv cov txheej txheem MBBR ntawm cov chaw kho dej khib nyiab hauv Suav teb yav qab teb ua piv txwv. Nws txheeb xyuas cov kev ua haujlwm ntawm cov nroj tsuag ua ntej thiab tom qab retrofit, nitrification kev ua tau zoo ntawm MBBR cheeb tsam, thiab cov qauv microbial hauv zej zog, qhia meej txog lub luag haujlwm ntawm MBBR txheej txheem hauv -situ peev xwm expansion. Lub hom phiaj yog los muab cov lus qhia thiab cov lus qhia rau kev tsim thiab kev ua haujlwm ntawm cov chaw kho dej khib nyiab zoo sib xws.
1 Project Overview
Lub chaw kho dej khib nyiab nyob rau sab qab teb Suav teb muaj peev xwm kho tau tag nrho ntawm 7.5 × 10⁴ m³ / d, nrog rau theem I muaj peev xwm ntawm 5 × 10⁴ m³ / d thiab Phase II ntawm 2.5 × 10⁴ m³ / d. Ob theem pib siv cov txheej txheem Hloov Bardenpho. Lub hom phiaj kev kho mob tseem ceeb yog cov dej khib nyiab hauv tsev los ntawm thaj chaw sau thiab ib feem ntawm cov dej khib nyiab los ntawm ib qho chaw ua lag luam. Cov dej khib nyiab zoo yuav tsum ua raws li Qib A tus qauv tau teev tseg hauv "Txoj Cai Kev Tso Tawm Ntawm Cov Khoom Siv Hluav Taws Xob rau Kev Kho Dej Hauv Nroog" (GB 18918-2002). Nrog txoj kev loj hlob sai ntawm kev tsim kho hauv nroog thiab kev lag luam, kev tso dej pov tseg tau nce zuj zus, thiab qhov project tau ua haujlwm ntawm lossis dhau qhov peev txheej. Xyoo 2021, raws li tsoomfwv cov cai xav tau, txoj haujlwm xav tau los nthuav nws lub peev xwm los ntawm kev ntxiv 2.5 × 10⁴ m³ / d raws li qhov ntsuas qub, mus txog tag nrho cov peev txheej kho mob ntawm 1 × 10⁵ m³ / d. Tus qauv effluent tseem nyob qib A ntawm GB 18918-2002. Cov tsim muaj peev xwm thiab effluent zoo yog qhia nyob rau hauvTable 1.
Lub cheeb tsam nyob ib ncig ntawm qhov project no yog av ua liaj ua teb, thiab muaj tsis txaus reserved av rau expansion nyob rau hauv thawj qhov chaw cog. Tsis tas li ntawd, thaum lub sij hawm pib kev tsim kho ntawm Theem II, cov pretreatment units twb tau ua raws li lub peev xwm ntawm 5 × 10⁴ m³ / d. Yog li ntawd, lub hom phiaj ntawm qhov project retrofit no yog txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau. Cov txheej txheem MBBR tau siv dav hauv -situ muaj peev xwm nthuav dav thiab kho dua tshiab ntawm cov chaw kho dej khib nyiab vim nws qhov "embedded" yam ntxwv. Piv txwv li, ib lub chaw kho dej khib nyiab nyob rau sab qaum teb Tuam Tshoj tau siv cov txheej txheem MBBR rau kev muaj peev xwm nce, ua kom muaj kev siv lub tank uas twb muaj lawm thiab cov txheej txheem ntws, ua tiav 20% hauv -situ muaj peev xwm nthuav dav nrog cov dej ntws ruaj khov raws li qib A cov qauv. Lwm cov nroj tsuag hauv Guangdong tau siv cov txheej txheem MBBR rau hauv -situ txhim kho kev kho mob lom neeg, ua tiav cov txiaj ntsig zoo ntawm 50% hauv -situ muaj peev xwm nthuav dav nrog cov dej ntws ruaj khov zoo dua li tus qauv tso tawm. Yog li ntawd, xav txog qhov xav tau tiag tiag ntawm cov chaw kho dej khib nyiab thiab kev ntsuam xyuas tag nrho xws li kev siv av thiab kev ua haujlwm, cov txheej txheem MBBR tau raug xaiv thaum kawg ua cov txheej txheem kho rau qhov kev nthuav dav retrofit.
2 Txheej Txheem Tsim
2.1 Txheej txheem Flow
Lub hauv paus ntawm lub peev xwm nthuav dav no yog txhawm rau txhim kho kev kho lub peev xwm ntawm cov tso tsheb hlau luam hauv -situ los ntawm MBBR, kom ntseeg tau tias muaj kev ruaj ntseg ua raws li cov qauv effluent txawm tias muaj 100% nce hauv kev khiav. Txij li cov thawj pretreatment thiab cov kev kho mob siab heev twb tau tsim rau ib tug muaj peev xwm ntawm 5 × 10⁴ m³ / d, qhov no retrofit tsom rau reusing cov chaw uas twb muaj lawm. Cov kev hloov pauv tseem ceeb yog cov tso tsheb hlau luam lom neeg, nrog rau kev tsim kho ntawm ib qho tshiab thib ob sedimentation tank teem kom tau raws li kev kho mob xav tau tom qab qhov ntws nce. Cov txheej txheem ntws tom qab retrofit tau qhia hauvDaim duab 1. Influent undergoes pretreatment los ntawm ntxhib / zoo cov ntxaij vab tshaus thiab ib tug grit chamber, ces nkag mus rau hauv Modified Bardenpho-MBBR tank rau tshem tawm carbon, nitrogen, phosphorus, thiab lwm yam kuab paug. Cov effluent los ntawm cov tso tsheb hlau luam lom neeg hla dhau los ntawm cov tso tsheb hlau luam sedimentation thiab lub siab - ua kom pom tseeb kom ruaj khov ua raws li SS thiab TP cov qauv. Tom qab tshuaj tua kab mob, qhov kawg effluent tawm mus rau hauv tus dej tau txais rau ecological dej ntxiv.
2.2 Cov Khoom Siv Hluav Taws Xob Hluav Taws Xob Retrofit
Lub hom phiaj ntawm lub tank retrofit yog qhia hauvDaim duab 2. Thaum ua ob npaug ntawm cov kev kho mob ntws, qhov ntim ntawm qhov qub anaerobic thiab anoxic zones tseem tsis hloov pauv . 20% ntawm qhov ntim los ntawm qhov qub aerobic cheeb tsam tau muab faib los ua ib qho chaw anoxic ntxiv, nthuav dav tag nrho cov anoxic zone ntim kom tau raws li qhov xav tau denitrification. Cov neeg nqa khoom raug tshem tawm tau ntxiv rau qhov seem ntawm thaj chaw aerobic los tsim thaj chaw aerobic MBBR. Txhawb kev ntsuas qhov nkag / qhov hluav taws xob thiab MBBR- cov khoom sib xyaw tshwj xeeb tau teeb tsa. Tus thawj saw aeration system tau hloov nrog lub hauv qab perforated aeration system los xyuas kom meej cov kua dej zoo ntawm cov cab kuj raug tshem tawm thiab tiv thaiv lawv cov dej ntws. Tom qab retrofit, tag nrho Hydraulic Retention Time (HRT) ntawm cov roj ntsha roj ntsha yog 8.82 h, nrog anaerobic zone HRT ntawm 1.13 h, anoxic zone HRT ntawm 3.05 h, thiab aerobic zone HRT ntawm 4.64 h. Tag nrho cov txheej txheem sab hauv rov siv dua yog 150%, thiab Sludge Hnub nyoog yog 16 hnub.
Regarding equipment, 4 sets of submersible mixers were added to the anoxic zone (Power P = 4 kW, Impeller Diameter D = 620 mm). SPR-III type suspended carriers were added to the aerobic MBBR zone, with a diameter of (25.0 ± 0.5) mm, height of (10.0 ± 1.0) mm, effective specific surface area >800 m² / m³, thiab qhov ceev ntawm 0.94 ~ 0.97 g / cm³. Qhov ntom ntom ntawm cov dej tom qab biofilm txuas, ua raws li kev lag luam tus qauv "High-density Polyethylene Suspended Carrier Fillers for Water Treatment" (CJ/T 461-2014). Qhov sib piv yog 45%. Ob pawg ntawm cov cab kuj raug tshem tawm - tshwj xeeb submersible mixers tau ntxiv (P=5.5 kW). Nees nkaum-ob pawg ntawm liftable aeration systems, 4 teeb tsa aeration systems, thiab 45 pawg ntawm cov npuas zoo aerators tau ntxiv. Ob lub twj tso kua mis sab hauv tau hloov pauv (Flow Q=1600 m³ / h, Lub taub hau H=0.60 m, P=7.5 kW).
2.3 Kev tsim kho tshiab Secondary Sedimentation Tank
Vim muaj kev nce ntxiv, cov twj tso kua mis thib ob uas twb muaj lawm tsis tuaj yeem ua tau raws li qhov yuav tsum tau ua. Yuav tsum muaj ib lub tank tshiab thib ob sedimentation los pab txhawb kom muaj peev xwm kho tau. Lub tank tshiab yog ua raws li cov thawj coj, siv lub voj voos kab rov tav ntws hom. Lub tank ntim tau zoo yog 4900 m³, nrog HRT=7 h. Ib lub twj tso kua mis- hom sludge scraper tau ntxiv (Operating Speed V=0.8 m/min). Rau submersible axial flow twj tso kua mis (sab nraud recycle twj) tau ntxiv (Q=180 m³ / h, H=4 m, P=5.5 kW). Ob lub twj tso kua mis pov tseg tau ntxiv (Q=105 m³ / h, H=11 m, P=7.5 kW).
3 Kev tshuaj xyuas ntawm MBBR Retrofit Effect
Kev ua haujlwm ua haujlwm ua ntej thiab tom qab Theem II retrofit, kev ua haujlwm ib txhij ntawm Phase I thiab Phase II, cov dej zoo hloov pauv raws li cov txheej txheem hauv Phase II, thiab nitrification peev txheej ntawm biofilm thiab tshem tawm cov sludge theem hauv Phase II tau txheeb xyuas los ntsuam xyuas cov txiaj ntsig zoo ntawm MBBR retrofit ntawm lub cev muaj peev xwm kho.
3.1 Kev sib piv kev ua haujlwm
Ua ntej lub retrofit, Phase II twb tau khiav hauj lwm saum toj no nws tsim ntws, nrog rau qhov tseeb nruab nrab ntws ntawm (3.02 ± 0.46) × 10⁴ m³ / d. Tom qab retrofit, qhov ntws ntxiv tau nce mus rau (5.31 ± 0.76) × 10⁴ m³ / d, qhov tseeb nce ntawm kwv yees li 76%. Qhov siab tshaj plaws ua haujlwm khiav mus txog 7.61 × 10⁴ m³ / d, 1.52 npaug ntawm tus nqi tsim. Influent thiab effluent zoo ua ntej thiab tom qab retrofit yog qhia nyob rau hauvRooj 2thiabDaim duab 3. Hais txog kev thauj khoom muaj txiaj ntsig, tom qab rov ua dua tshiab, ammonia nitrogen (NH₃-N), tag nrho cov nitrogen (TN), COD, thiab TP loadings tau nce mus rau 1.61, 1.66, 1.60, thiab 1.53 npaug ntawm pre-retrofit theem, feem. Nyob rau hauv cov nqe lus ntawm qhov tseeb influent/effluent zoo, influent NH₃-N thiab TN ua ntej/tom qab retrofit yog (22.15 ± 3.73)/(20.17 ± 4.74) mg/L thiab (26.28 ± 4.07)/(23.19 ± 3.66) mg./L. Effluent NH₃-N thiab TN ua ntej/tom qab retrofit yog (0.16 ± 0.14) / (0.14 ± 0.08) mg/L thiab (8.62 ± 1.79)/(7.01 ± 1.76) mg/L, nrog rau qhov nruab nrab tshem tawm ntawm 99.28% / 99.28% / 67.20% / 69.77%, feem. Txawm hais tias muaj kev nce ntxiv hauv kev ntws thiab muaj peev xwm thauj khoom tom qab retrofit, effluent zoo tseem zoo dua ua ntej retrofit. Qhov nce anoxic cheeb tsam ntim tau ua kom zoo TN tshem tawm, nrog cov dej ntws tawm TN ntxiv txo tom qab retrofit. Qhov chaw aerobic tau ua tiav qhov kev txhim kho tseem ceeb hauv nitrification muaj peev xwm los ntawm kev tshem tawm cov khoom siv biofilm. Txawm tias muaj 20% txo qis hauv aerobic cheeb tsam ntim piv rau ua ntej-retrofit thiab tseem ceeb nce nyob rau hauv ntws thiab influent loading, heev npaum NH₃-N tshem tawm tau khaws cia. Influent COD thiab TP ua ntej / tom qab retrofit yog (106.82 ± 34.37) / (100.52 ± 25.93) mg / L thiab (2.16 ± 0.54) / (1.96 ± 0.49) mg / L, feem. Effluent COD thiab TP ua ntej / tom qab retrofit yog (10.76 ± 2.04) / (11.15 ± 3.65) mg / L thiab (0.14 ± 0.07) / (0.17 ± 0.05) mg / L, nrog qhov nruab nrab tshem tawm ntawm 89.93% / 93.59.3% / 89.52% thiab hwm Tom qab retrofit, effluent zoo tseem nyob ruaj khov zoo dua li tus qauv tsim tawm.
Cov ntaub ntawv ua haujlwm txij lub Kaum Ib Hlis mus txog Lub Ib Hlis ntawm xyoo tom ntej (post-retrofit) tau raug xaiv ntxiv los sib piv qhov kev ua tau zoo ntawm Phase I thiab Phase II nyob rau hauv qis- qhov kub thiab txias (tsawg kawg yog 12℃). Influent thiab effluent pollutant concentrations rau ob theem yog qhia nyob rau hauvDaim duab 4. Nyob rau lub caij ntuj no qis- qhov kub thiab txias, cov dej ntws los ntawm ob txheej txheem tau ruaj khov zoo dua li tus qauv tsim tawm. Tshwj xeeb tshaj yog rau NH₃-N tshem tawm, uas yog qhov raug rau qhov kub thiab txias, nrog NH₃-N concentration ntawm (18.98±4.57) mg/L, Phase I effluent NH₃-N yog (0.27±0.0.17) mg/L Phase II mg / L, ob qho tib si ua kom pom kev ua haujlwm zoo rau qhov kub thiab txias. Qhov tseem ceeb, tom qab MBBR retrofit nyob rau theem II, thaj tsam aerobic HRT tsuas yog 66.07% ntawm qhov ntawd hauv Phase I, ua tiav qhov kev txhim kho tseem ceeb hauv nitrification kev ua tau zoo.
3.2 Kev Ntsuam Xyuas Kev Ua Haujlwm ntawm MBBR Zone
Txhawm rau txiav txim siab qhov tshwm sim tiag tiag ntawm txhua qhov chaw ua haujlwm, cov qauv dej los ntawm qhov kawg ntawm txhua qhov chaw ua haujlwm hauv Phase I thiab Phase II tau muab coj los ntsuas rau qhov sib npaug. Cov txiaj ntsig tau qhia hauvDaim duab 5. Influent NH₃-N concentrations yog 18.85 mg/L thiab 18.65 mg/L, thiab effluent NH₃-N concentrations yog 0.35 mg/L thiab 0.21 mg/L, nrog NH₃-N removal rates 1.4% 9.8. Los ntawm kev hloov pauv nitrogen profile, NH₃-N tshem tawm hauv Phase II feem ntau tshwm sim hauv thaj chaw aerobic MBBR. NH₃{13}}N concentration ntawm MBBR zone effluent yog 0.31 mg/L, pab 99.46% rau tag nrho NH₃-N tshem tawm, twb zoo dua li tus qauv tso tawm. Tom ntej no aerobic activated sludge zone tau ua lub luag haujlwm tiv thaiv. Tsis tas li ntawd, cov chaw kho dej khib nyiab siv MBBR hauv thaj chaw aerobic feem ntau nthuav tawm Simultaneous Nitrification thiab Denitrification (SND). Txawm li cas los xij, hauv qhov project no, tsis muaj Total Inorganic Nitrogen (TIN) tshem tawm tau pom nyob rau hauv thaj chaw aerobic MBBR, uas tej zaum yuav cuam tshuam rau qhov cuam tshuam tsis zoo ntawm substrate concentration hauv qhov project no.
Txhawm rau tshawb xyuas ntxiv cov txiaj ntsig ntawm kev ntxiv cov cab kuj raug tshem tawm ntawm qhov kev ua haujlwm ntawm nitrification, supernatant los ntawm thaj chaw anoxic effluent ntawm Phase I raug coj mus. Nitrification kev ua tau zoo tau ua nyob rau theem I ntshiab sludge, Phase II ntshiab sludge, Phase II ntshiab biofilm, thiab Phase II ua ke biofilm-sludge system. Nyob rau hauv cov xwm txheej raws li qhov project tiag tiag (carrier filling ratio, sludge concentration, dej kub), nrog DO tswj ntawm 6 mg / L los txiav txim siab zoo nitrification kev ua tau zoo. Cov txiaj ntsig tau qhia hauvTable 3. Cov nqi nitrification rau Phase I pure sludge, Phase II pure sludge, Phase II pure biofilm, thiab Phase II ua ke biofilm-sludge system yog 0.104, 0.107, 0.158, thiab 0.267 kg/(m³·d), feem. Qhov sib ntxiv ntawm cov neeg nqa khoom raug tshem tawm tau txhim kho qhov kev ua haujlwm ntawm nitrification. Tus nqi nitrification ntawm Phase II ua ke biofilm-sludge system mus txog 2.57 npaug ntawm Phase I ntshiab activated sludge system. Ntxiv mus, cov ntshiab biofilm load twb siab dua cov activated sludge load, ho txhim kho lub cev poob siab load kuj. Hauv Phase II ua ke, biofilm pab txhawb 59.92% rau nitrification, tuav txoj haujlwm tseem ceeb.
3.3 Rationality Analysis ntawm Retrofit
Txhawm rau txheeb xyuas qhov laj thawj ntawm kev siv biofilm ua ke-sludge MBBR txheej txheem rau qhov kev rov ua dua tshiab no, suav nrog cov txiaj ntsig ntawm cov cab kuj ntxiv, lub kaw lus poob siab tsis kam, thiab kev sib raug zoo ntawm kev nce ntxiv thiab cov cab kuj ntxiv. Yog tias Phase II ntawm qhov project no tsis tau rov qab kho dua thiab siv cov txheej txheem ua kom cov sludge ib txwm siv, raws li cov qauv tsim muaj txiaj ntsig / cov dej ntws NH₃-N thiab qhov zoo tshaj plaws volumetric nitrification tus nqi ntawm Phase I activated sludge (DO=6 mg/L), lub xam effluent NH₃5} yuav ua tsis tiav {4. tus qauv effluent. Yog hais tias xam raws li qhov zoo tshaj plaws nitrification tus nqi tau los ntawm Theem II ua ke system xeem, ntawm lub tsim influent flow, Phase II yuav zam lub siab tshaj plaws influent NH₃-N concentration txog li 55 mg / L, uas yog 2.20 npaug ntawm tus nqi tsim, ua kom lub cev poob siab load kuj. Yog li ntawd, kev siv MBBR rau qhov retrofit no yog qhov tsim nyog thiab ua kom muaj kev ruaj ntseg ua raws li cov qauv effluent. Yog tias Phaj I kuj tau rov qab kho dua tshiab nrog cov txheej txheem MBBR, raws li tsim los ntawm cov khoom siv hluav taws xob / cov pa phem ntau ntxiv, kev kho cov dej ntws tuaj yeem nce ntxiv los ntawm ntau dua 1-fold, muab qhov muaj peev xwm rau cov nroj tsuag kho dej khib nyiab kom haum rau kev loj hlob hauv nroog sai thiab ua tiav kev hloov kho kom zoo.
4 Biofilm Attachment Status thiab Microbial Analysis
Daim ntawv txuas biofilm ntawm cov cab kuj raug tshem tawm hauv qhov project no tau qhia hauvDaim duab 6. Biofilm uniformly coated lub puab nto ntawm cov cab kuj, yog ntom yam tsis muaj flocculent cov ntaub ntawv nyob rau hauv lub carrier pores. Qhov nruab nrab thickness yog (345.78 ± 74.82) μm. Qhov nruab nrab biofilm biomass yog (18.87 ± 0.93) g / m², Volatile Suspended Solids (VSS) / SS ratio yog ruaj khov ntawm 0.68 ± 0.02, thiab qhov nruab nrab VSS yog (12.77 ± 0.61) g / m².
Txhawm rau tshawb nrhiav ntxiv txhim kho cov txiaj ntsig ntawm MBBR retrofit ntawm kev kho lub cev muaj peev xwm los ntawm kev saib xyuas me me, cov qauv ntawm Phase I activated sludge, Phase II activated sludge, thiab biofilm tau coj mus rau 16S amplicon siab -throughput sequencing. Qhov txheeb ze ntawm cov kab mob microorganisms nyob rau theem genus hauv qhov system tau qhia hauvDaim duab 7.
Qhov tseem ceeb ntawm nitrifying genera ntawm cov khoom thauj khoom raug tshem tawm yog Nitrospira thiab Nitrosomonas, nrog cov txheeb ze ntawm 7.98% thiab 1.01%, feem. Nyob rau hauv sib piv, cov tseem ceeb nitrifying genus nyob rau theem I thiab theem II activated sludge yog Nitrospira, nrog abundances ntawm 1.05% thiab 1.27%, feem. Nitrospira yog cov nitrifying genus tshaj plaws hauv cov nroj tsuag kho dej khib nyiab. Ntau yam ntawm nws cov tsiaj tau raug pov thawj tias muaj peev xwm ua tiav ammonia oxidation (comammox), txhais tau hais tias ib tus kab mob tuaj yeem ua tiav cov txheej txheem los ntawm ammonia mus rau nitrate. Cov txheej txheem MBBR, nyob rau hauv daim ntawv ntawm biofilm, ua tau zoo enrichment ntawm Nitrospira, nrog ib tug txheeb ze abundance 7.58 lub sij hawm nyob rau hauv activated sludge, muab ib tug microscopic foundation rau kev txhim kho cov system nitrification kev ua tau zoo. Nws kuj tseem tuaj yeem pom tau tias cov txheeb ze ntawm cov kab mob nitrifying ntau nyob rau hauv cov activated sludge los ntawm tib lub cev raws li biofilm (Phase II) yog me ntsis siab dua nyob rau theem I ntshiab activated sludge system. Qhov no tej zaum yuav yog vim hais tias tso biofilm los ntawm cov neeg nqa khoom tshem tawm inoculated lub tshuab ua kom cov sludge thaum lub sij hawm rov ua dua tshiab, ua rau cov txheeb ze ntau ntawm cov kab mob nitrifying hauv cov sludge.
Qhov tseem ceeb ntawm denitrifying genera nyob rau hauv ob qho tib si lub cev yog tsuas yog enriched nyob rau hauv lub activated sludge thiab kuj zoo sib xws nyob rau hauv muaj pes tsawg leeg, xws li Terrimonas, Flavobacterium, Dechloromonas, Hyphomicrobium, thiab lwm yam. Cov txheeb ze ntawm denitrifying genera nyob rau hauv Phase I thiab Phase II yog 8.76% thiab 7.52%. Los ntawm qhov kev xav ua haujlwm, ntxiv rau denitrification, qee hom tsiaj hauv Terrimonas tuaj yeem degrade anthracene-zoo li tshuaj; Flavobacterium tuaj yeem degrade biodegradable plastics (piv txwv li, PHBV); Hyphomicrobium tuaj yeem siv ntau yam tshuaj lom thiab nyuaj-rau-degrade cov organic tebchaw rau denitrification, xws li dichloromethane, dimethyl sulfide, methanol, thiab lwm yam. Lub zog ntawm qhov project no muaj qee cov dej khib nyiab, ua rau tshwj xeeb ntawm cov zej zog microbial nyob rau hauv lub sij hawm ntev - acclimation. Txawm hais tias qhov project no tsis tau nthuav tawm cov teebmeem macroscopic SND tseem ceeb, qee cov pab pawg ua haujlwm denitrifying tseem pom nyob rau ntawm cov khoom siv biofilm tshem tawm, suav nrog Hyphomicrobium, Dechloromonas, Terrimonas, thiab OLB13, nrog rau tag nrho feem ntawm 2.78%. Qhov no qhia tau hais tias tom qab biofilm ncav cuag ib lub thickness, lub anoxic / anaerobic microenvironments tsim nyob rau hauv yuav muab tej yam kev mob rau cov enrichment ntawm denitrifying kab mob, kuj muab qhov muaj peev xwm rau SND tshwm sim nyob rau hauv aerobic MBBR cheeb tsam. Tsis tas li ntawd, Proteiniclasticum tau kuaj pom hauv Phase I thiab Phase II sludge, nrog cov txheeb ze ntau ntawm 1.09% thiab 1.18%, feem. Cov genus no muaj peev xwm zoo rau decomposing thiab hloov cov tshuaj proteinaceous. Nws qhov kev nplua nuj tuaj yeem cuam tshuam nrog kev muaj ntau lub tuam txhab khoom noj siv mis hauv qhov chaw sau ntawm qhov project no.
Qhov tseem ceeb, qhov txheeb ze ntawm Candidatus Microthrix nyob rau theem kuv ua kom cov sludge mus txog 3.72%. Nws yog ib hom kab mob filamentous nyob rau hauv activated sludge, feem ntau txuam nrog sludge bulking. Txawm li cas los xij, nws cov txheeb ze nplua nuj nyob rau theem II sludge thiab biofilm tsuas yog 0.57% thiab 1.03%, feem. Tom qab retrofitting nrog cov txheej txheem MBBR, lub fluidization ntawm tshem tawm cov cab kuj muaj cov nyhuv shearing ntawm cov kab mob filamentous, txo qhov yuav muaj filamentous bulking nyob rau hauv lub activated sludge.
5 Kev txheeb xyuas nyiaj txiag
Kev siv hluav taws xob hauv ib lub cubic meter ua ntej thiab tom qab qhov kev hloov pauv no yog 0.227 kWh / m³ thiab 0.242 kWh / m³, feem. Ntawm tus nqi hluav taws xob ntawm 0.66 RMB / (kWh), tus nqi hluav taws xob ua haujlwm yog 0.150 RMB / m³ thiab 0.160 RMB / m³. Qhov kev siv hluav taws xob nce ntxiv yog vim qhov kev sib xyaw ntawm thaj chaw anoxic tshiab thiab cov khoom siv hluav taws xob ntxiv los ntawm cov tshiab thib ob sedimentation tank. Cov tshuaj phosphorus tshem tawm siv hauv qhov project no yog Polyferric Chloride (PFC) thiab Polyacrylamide (PAM). Kev noj zaub mov tseem zoo ib yam ua ntej thiab tom qab retrofit: PFC ntau npaum 2.21 t / d, tus nqi 0.014 RMB / m³; PAM noj 17.081 kg/d, nqi 0.0028 RMB/m³. Qhov project no siv tag nrho cov pa roj carbon monoxide hauv cov khoom siv raw rau denitrification. Tsis muaj lwm cov organic carbon tau ntxiv ua ntej lossis tom qab retrofit. Tus nqi hluav taws xob ncaj qha thiab tshuaj lom neeg rau ib lub cubic meter ua ntej thiab tom qab retrofit yog 0.167 RMB / m³ thiab 0.177 RMB / m³, feem.
6 Cov ntsiab lus thiab Outlook
(1) Theem II ntawm lub chaw kho dej khib nyiab yav qab teb tau siv cov txheej txheem MBBR rau kev nthuav dav rov qab, daws teeb meem xws li av tsis txaus. Tom qab retrofit, cov kev kho mob tau nce los ntawm (3.02 ± 0.46) × 10⁴ m³ / d rau (5.31± 0.76) × 10⁴ m³ / d, ua tiav 76% hauv -situ muaj peev xwm nthuav dav. Qhov kev ua haujlwm siab tshaj plaws tau mus txog 1.52 npaug ntawm tus nqi tsim, nrog cov dej ntws ruaj khov zoo dua li tus qauv tsim tawm.
(2) Los ntawm embedding cov txheej txheem MBBR nyob rau hauv cov theem lom, muaj txiaj ntsig zoo thiab ruaj khov NH₃-N tshem tawm tau ua tiav nyob rau lub caij ntuj no qis- qhov kub thiab txias, txawm tias aerobic HRT tsuas yog 66.07% ntawm qhov ntawd hauv cov txheej txheem activated sludge. MBBR cheeb tsam pab txhawb 99.46% rau NH₃-N tshem tawm. Yog tias Phase II tsis tau rov kho dua, nyob rau hauv tib qhov ntws thiab dej zoo, NH₃-N yuav ncav cuag 5.55 mg / L. Yog li ntawd, kev siv MBBR rau qhov retrofit no yog qhov tsim nyog thiab tsim nyog.
(3) Cov ntaub ntawv pov tseg cov khoom siv biofilm txhim kho cov txiaj ntsig zoo ntawm cov tub ntxhais nitrifying genus Nitrospira. Nws cov txheeb ze nplua nuj nyob rau hauv biofilm yog 7.58 lub sij hawm uas nyob rau hauv lub activated sludge, muab ib tug microscopic foundation rau kev txhim kho cov system nitrification kev ua tau zoo. Tsis tas li ntawd, kev txhim kho ntawm denitrifying genera hauv biofilm muaj qhov ua tau rau SND tshwm sim.
Qhov project no siv cov biofilm ua ke- cov txheej txheem sludge kom ua tiav hauv -situ peev xwm nce. Txawm li cas los xij, kev ua haujlwm tiag tiag tseem txwv los ntawm kev tuav thiab rov ua haujlwm ntawm cov sludge, tiv thaiv kev txhim kho ntxiv ntawm kev kho mob. Tam sim no, cov txheej txheem biofilm ntshiab tau siv rau hauv cov haujlwm tiag tiag, tso tseg tag nrho cov activated sludge thiab siv lub siab -load cov yam ntxwv ntawm biofilm kom tshem tawm cov pa phem, tsis txwv los ntawm cov kev txwv activated sludge. Qhov no muab cov kev daws teeb meem tshiab rau kev tsim kho tshiab, kho dua tshiab, lossis nthuav tawm cov chaw kho dej khib nyiab.