Daim ntawv thov ntawm BIOLAK txheej txheem hauv kev txhim kho cov chaw kho dej khib nyiab rau Quasi-Class IV Standards
Qhia rau Tuam Tshoj thaum ntxov xyoo pua 21st, BIOLAK txheej txheem tau txais kev siv dav hauv kev kho dej khib nyiab hauv nroog vim nws cov qauv yooj yim thiab cov nqi peev tsawg. Nyob rau hauv xyoo tas los no, nrog rau nruj ntawm cov qauv tso tawm thiab nce automation, feem ntau BIOLAK cov nroj tsuag tam sim no ntsib kev hloov kho dua tshiab. Kev txhim kho xws li ntxiv cov cab kuj raug tshem tawm, cov tso tsheb hlau luam rov qab, thiab rov txhais cov chaw ua haujlwm tau siv los txhim kho nitrogen thiab phosphorus tshem tawm. Thaum cov nroj tsuag tsim tshiab feem ntau tau txais A² / O thiab cov txheej txheem oxidation ditch, muaj ob peb cov lus ceeb toom txog qhov ua tau zoo ntawm BIOLAK, tshwj xeeb tshaj yog nyob rau hauv cov qauv emission nruj. Cov txheej txheem BIOLAK siv viav vias aeration chains los tsim cov anoxic thiab aerobic aerobic zones, qhov tseem ceeb ua haujlwm raws li ntau-theem A / O txheej txheem. Los ntawm kev ua haujlwm kom zoo, cov dej ntws zoo tuaj yeem ua tau raws li qhov quasi -Class IV nto dej tus qauv.
1 Project Background
Lub chaw kho dej khib nyiab hauv Hebei Xeev siv cov txheej txheem BIOLAK ua nws cov thev naus laus zis tseem ceeb. Cov dej ntws tawm ntawm 18,000 txog 22,000 m³ / d, qhov nruab nrab ntawm 19,000 m³ / d, kho cov dej phwj hauv nroog hauv nroog thiab cov dej ua liaj ua teb me me. Cov tsim muaj peev xwm thiab effluent qualities yog qhia nyob rau hauvTable 1. Tus qauv tso tawm thawj zaug yog Qib A tus qauv ntawm * "Tshem Tawm Cov Kabmob Cov Kabmob rau Kev Kho Dej Hauv Nroog" (GB 18918-2002)*. Tom qab kev txhim kho uas suav nrog kev faib ib cheeb tsam anaerobic los txhim kho denitrification thiab dephosphorization, cov nroj tsuag tam sim no ua raws li qhov tseem ceeb tswj cheeb tsam txwv ntawm * "Dej Pollutant Discharge Standards for the Daqing River Basin" (DB13/2795-2018)*. Tsuas yog tag nrho cov nitrogen, tag nrho lwm cov kev ntsuas ua tau raws li Chav Kawm IV cov qauv teev tseg hauv * "Environmental Quality Standards for Surface Water" (GB 3838-2002)*. Cov txheej txheem ntws tau qhia hauvDaim duab 1.
Cov nroj tsuag siv sodium hypochlorite rau kev tua kab mob. Sludge yog dewatered los ntawm siab - phaj siab thiab thav duab pom kom qis dua 60% cov ntsiab lus noo noo ua ntej thauj mus rau co- ua hauv cov cement kiln.
Kev koom tes ntawm txhua chav kho mob rau kev tshem tawm cov pa phem raug xam raws li qhov sib npaug ntawm pawg, nrog rau cov txheej txheem tshwj xeeb hais los ntawm cov ntaub ntawv.
2 Kev Tswj Xyuas Kev Ua Haujlwm Zoo Tshaj Plaws
Ntau qhov kev ntsuas kev ua kom zoo tau siv thaum lub sijhawm ua haujlwm txhawm rau txhim kho kev ruaj khov thiab ua tiav lub zog thiab txuag nqi.
2.1 Txhim kho cov pa oxygen (DO) tswj
BIOLAK retrofit tej yaam num uas twb muaj lawm feem ntau nco ntsoov nws tsis muaj zog zoning raws li ib tug multi-theem A/O variant, ua rau tsis tshua muaj denitrification efficiency. Hauv qhov project no, thaum ua kom muaj kev ua raws li ammonia nitrogen, qhov siab tshaj plaws DO ntawm qhov kawg ntawm thaj chaw aeration tau khaws cia ntawm 0.5-1.0 mg / L, qis dua li cov kev cai tswj hwm DO.
2.2 Txhim kho cov txheej txheem cov ntaub ntawv saib xyuas
Txhawm rau coj DO tswj thiab kev siv cov pa roj carbon monoxide sab nraud, nitrate nitrogen thiab ammonia nitrogen tau saib xyuas thaum kawg ntawm thaj chaw anaerobic thiab BIOLAK tank los txiav txim siab txog kev tswj hwm qhov zoo. Thaum lub sijhawm ua haujlwm, kev siv cov pa roj carbon monoxide sab nraud raug txo lossis nres thaum nitrate nitrogen thaum kawg ntawm thaj chaw anaerobic.<2 mg/L, and increased when it was ≥2 mg/L. Similarly, blower output was reduced to lower DO to 0.5 mg/L when ammonia nitrogen at the end of the BIOLAK tank was ≤0.5 mg/L, and increased to raise DO to 1.0 mg/L when it was ≥0.5 mg/L. Adjustments to carbon source dosage and blower frequency were made every 8–16 hours, with each adjustment ranging from 5% to 15%.
2.3 Kev teeb tsa Internal Effluent Control Targets
Txhawm rau kom ua raws li kev ruaj ntseg, lub hom phiaj kev tswj hwm sab hauv tau teeb tsa ntawm 30% -80% ntawm qhov tso tawm txwv, raws li qhov nyuaj ntawm kev tswj hwm txhua qhov muaj kuab paug. Tshaj dhau cov kev txwv sab hauv no ua rau cov txheej txheem tam sim no hloov kho kom rov qab cov dej ntws tawm mus rau qhov kev lees paub. Lub hom phiaj ntawm kev tswj hwm txhua xyoo rau COD, ammonia nitrogen, tag nrho nitrogen, thiab tag nrho phosphorus yog 15 mg / L, 0.5 mg / L, 12 mg / L, thiab 0.12 mg / L, raws li.
2.4 Tswj kom tsim nyog Sludge Concentration
Sludge khib nyiab tau hloov kho raws li ntws, thauj khoom, thiab caij nyoog. Lub sij hawm khaws cia sludge (SRT) tau khaws cia ntawm 15-25 hnub, thiab cov kua dej sib xyaw ua ke (MLSS) concentration ntawm 2,500–4,500 mg / L. Tshwj xeeb, MLSS tau tswj hwm ntawm 2,500–3,500 mg / L nyob rau lub caij ntuj sov thiab lub caij nplooj zeeg, nrog cov sludge load txog li 0.06 kgCOD/(kgMLSS·d), thiab ntawm 3,500–4,500 mg/L nyob rau lub caij ntuj no thiab caij nplooj ntoos hlav, nrog ib tug sludge load txog li 0.04 kgCOD (MLSS·d).
2.5 Kho Kev Ua Haujlwm ntawm Kev Kho Mob Siab Tshaj Plaws
Tsawg kub nyob rau lub caij ntuj no cuam tshuam flocculation thiab sedimentation. Kev lim dej tsis tu ncua ntawm V- hom lim tuaj yeem ua rau kom cov kua dej tshem tawm thiab COD nce siab. Yog li ntawd, thaum lub caij ntuj no ua haujlwm, rov qab rov qab zaus tau nce ntxiv raws li kev ua haujlwm ntawm coagulation, thiab sludge tawm los ntawm coagulation-sedimentation tank tau ua kom nrawm dua los txo cov dej tawm ntawm cov khib nyiab pov tseg.
3 Kev kho mob ua tau zoo
Ib xyoos ib zaug influent COD ranges ntawm 109 mus rau 248 mg / L, nruab nrab 176 mg / L. Effluent COD ranges ntawm 9.5 mus rau 20.1 mg / L, nruab nrab 12.1 mg / L. Thaum effluent COD tshaj lub hom phiaj tswj sab hauv (15 mg / L), lim rov qab zaus tau nce ntxiv kom txo cov khib nyiab pov tseg. Nws raug nquahu kom hloov cov coagulation{10}}sedimentation tank mus rau qhov siab -density lossis magnetic coagulation-sedimentation tank kom zoo dua coagulation efficiency.
Ib xyoos ib zaug influent ammonia nitrogen ranges ntawm 17.8 mus rau 54.9 mg / L, nruab nrab 31.9 mg / L. Cov kua dej ammonia nitrogen nyob ntawm 0.12 txog 1.30 mg / L, nruab nrab 0.5 mg / L. Thaum nws dhau lub hom phiaj kev tswj hwm sab hauv, aeration tau hloov kho raws li kev ntsuas kev ua kom zoo. Cov dej ntws zoo ruaj khov ua tau raws li qhov tseem ceeb tswj cheeb tsam txwv ntawm * DB13/2795-2018 * thoob plaws hauv lub xyoo.
Vim muaj cov pa roj carbon tsawg tsawg, qhov kev tsom mus rau kev ua kom zoo ntawm cov txheej txheem los txhim kho nitrogen thiab phosphorus tshem tawm, aiming rau lub zog thiab kev txuag nqi.
3.1 DO tswj kev ua kom zoo tshaj plaws thiab tshem tawm tag nrho Nitrogen
Ib xyoos ib zaug influent tag nrho nitrogen (TN) ranges ntawm 20.3 mus rau 55.6 mg / L (saibDaim duab 2), qhov nruab nrab 42.1 mg / L. Effluent TN ranges ntawm 2.5 mus rau 14.2 mg / L, nruab nrab 8.8 mg / L, nyob rau hauv lub hom phiaj tswj sab hauv (12 mg / L). Qhov nruab nrab TN tshem tawm tus nqi yog 79.1%. Nrog rau cov sludge recycle piv ntawm 90% (tsis muaj kev sib xyaw cawv rov ua dua), qhov theoretical denitrification efficiency yog 47.4%, qhia tias denitrification kuj tshwm sim nyob rau hauv lwm cov txheej txheem zones tshaj li anaerobic selector. Cov kev hloov pauv hauv nitrogen raws li kev kho tsheb ciav hlau hauv ib lub voj voog raug qhia hauvDaim duab 3.
Hauv ib lub voj voog ib txwm, qhov muaj zog TN yog 42.0 mg / L, nrog rau qhov sib npaug ntawm ammonia thiab nitrate nitrogen yog 35.2 mg / L. Tom qab anaerobic selector, TN yog 16.7 mg / L, uas ua rau 43.5% tshem tawm tus nqi los ntawm huab hwm coj sib npaug, raws li tus nqi theoretical. Lub tank BIOLAK tau pab txhawb 24.0% TN tshem tawm. Effluent TN tau txo qis ntxiv rau hauv lub tank thib ob, ua rau 11.3% tshem tawm ntxiv, feem ntau yog vim nws lub sijhawm hydraulic ntev (8.6 teev) tso cai rau cov pa roj carbon monoxide endogenous{10}}tsav denitrification. Lwm cov units tau pab 1.9% tshem tawm. Qhov kawg ntawm TN effluent yog 8.1 mg / L, nrog rau tag nrho cov kev tshem tawm ntawm 80.7%.
Kev paub txog kev ua haujlwm qhia tau hais tias DO tswj yog qhov tseem ceeb rau kev tshem tawm TN hauv cov txheej txheem BIOLAK. Hauv cov txheej txheem ib txwm ua, DO feem ntau ntsuas qhov kawg ntawm thaj chaw aerobic hauv cov qauv channel uas DO yog qhov sib xws ntawm tus ntoo khaub lig-section. Txawm li cas los xij, hauv BIOLAK lub tank, qhov chaw aeration kawg yog ze li ntawm 70 meters dav, nrog DO nce los ntawm txoj kab nqes mus rau qhov chaw, qhov sib txawv ntawm 0.5-1.0 mg / L. Yog li ntawd, qhov chaw ntawm DO probes yuav tsum tau ua tib zoo saib xyuas.
Los ntawm kev tswj hwm qhov siab tshaj plaws DO thaum kawg ntawm BIOLAK aeration cheeb tsam, qhov chaw anoxic tsim nyog rau denitrification tau ua kom zoo. Simultaneous nitrification thiab denitrification (SND) siv cov pa roj carbon monoxide endogenous tau ua tiav, ua rau kev tshem tawm TN zoo.
3.2 Tag nrho Phosphorus Tshem Tawm thiab Kev Ua Haujlwm Zoo
Txhua xyoo muaj peev xwm ntawm tag nrho cov phosphorus (TP) nyob ntawm 1.47 txog 4.80 mg / L (saibDaim duab 4), qhov nruab nrab 2.99 mg / L. Cov kua dej TP nyob ntawm 0.04 txog 0.17 mg / L. Phosphorus tshem tawm tus neeg saib xyuas ntau npaum li cas tau hloov kho raws li kev tswj hwm lub hom phiaj (0.12 mg / L). Qhov nruab nrab TP effluent concentration yog 0.07 mg / L, ruaj khov raws li tus qauv tso tawm, nrog qhov nruab nrab TP tshem tawm tus nqi ntawm 98.3%.
Kev hloov pauv hauv phosphate raws li kev kho tsheb ciav hlau hauv ib lub voj voog raug pom hauvDaim duab 5.
Influent phosphate yog 2.70 mg / L, thiab rov qab sludge phosphate yog 0.58 mg / L, ua rau theoretical phosphate nkag mus rau anaerobic selector 1.70 mg / L. Tom qab anaerobic phosphorus tso tawm los ntawm polyphosphate- cov kab mob sib sau (PAOs), phosphate concentration mus txog 3.2 mg / L. phosphate concentration ratio (qhov siab tshaj plaws nyob rau hauv anaerobic cheeb tsam / influent) yog 1.9, qhia qhov tseem ceeb tso tawm. Qhov laj thawj tseem ceeb yog qhov ua tau zoo denitrification nyob rau hauv qis DO, ua rau tsis tshua muaj nitrate concentration nyob rau hauv lub rov qab sludge mus rau anaerobic cheeb tsam, tswj ib tug zoo anaerobic ib puag ncig (ORP feem ntau qis dua -200 mV) thiab txhawb phosphorus tso tawm.
Tom qab BIOLAK aeration cheeb tsam, muaj ntau yam phosphorus uptake tshwm sim, txo cov phosphate concentration thaum kawg mus rau 0.3 mg / L, ua tiav ib tug lom phosphorus tshem tawm efficiency ntawm 88.9%. Tom qab cov sedimentation thiab stabilization tso tsheb hlau luam, phosphate concentration nce mus rau 0.64 mg / L. Kev tshuaj xyuas qhia tias qhov no yog vim HRT ntev nyob rau hauv lub tank sedimentation thiab nruj tswj DO nyob rau hauv lub BIOLAK tank, tsim ib tug anaerobic mob nyob rau hauv lub sedimentation tank thiab ua rau theem nrab phosphorus tso tawm. Tom qab siv tshuaj lom neeg hauv chav tsev coagulation, phosphate effluent raug txo mus rau 0.06 mg / L. Yog li ntawd, xav txog cov nqi kev lag luam thiab kev ua haujlwm tsis yooj yim, kev txi qee qhov kev tshem tawm cov phosphorus lom neeg los txhim kho denitrification yog ib lub tswv yim zoo rau cov nroj tsuag zoo sib xws.
4 Cov Nqi Ua Haujlwm
Cov nqi khiav lag luam ncaj qha suav nrog hluav taws xob, tshuaj lom neeg, thiab pov tseg sludge. Raws li kev txheeb cais txhua xyoo, qhov tshwj xeeb siv hluav taws xob yog 0.66 kWh / m³. Nrog rau tus nqi hluav taws xob ntawm 0.65 CNY / kWh (raws li kev sib xyaw ntawm qhov siab tshaj / tawm- cov nqi siab), tus nqi hluav taws xob yog 0.429 CNY / m³. Qhov kev noj no yog nyob rau sab siab dua raws li "Kev Ntsuas Tus Txheej Txheem rau Kev Ua Haujlwm Zoo ntawm Lub Nroog Lub Chaw Kho Dej Kho Dej", feem ntau yog vim qhov kev siv cov pa oxygen tsawg dua ntawm lub tshuab aeration. Cov nqi tshuaj, suav nrog sodium acetate, phosphorus tshem tawm tus neeg sawv cev, PAM, sodium hypochlorite, thiab cov tshuaj dewatering, tag nrho 0.151 CNY / m³. Kev siv tshwj xeeb thiab cov nqi tau qhia hauvRooj 2.
Sludge feem ntau yog los ntawm cov khoom siv roj ntsha thiab tshuaj lom neeg (coagulation tank) qhov chaw. Siab - phaj siab thiab thav duab pom yog siv nrog txiv qaub thiab ferric chloride ua cov tshuaj txias. Txiv qaub noj yog li 25% ntawm qhov hnyav sludge qhuav. Dewatered ncuav mog qab zib muaj cov ntsiab lus noo ntawm 60%. Txhua hnub dewatered sludge ntau lawm yog kwv yees li 9 tons, nrog rau qhov tshwj xeeb qhuav sludge tawm los ntawm 0.15%. Sludge kev thauj mus los raug nqi 250 CNY / ton, ua rau cov nqi pov tseg ntawm 0.118 CNY / m³. Yog li ntawd, tag nrho cov nqi tsim khoom ncaj qha yog 0.698 CNY / m³.
5 Cov lus xaus
① Lub chaw kho dej khib nyiab hauv Hebei Xeev, siv cov txheej txheem BIOLAK los kho cov dej khib nyiab hauv nroog, ua haujlwm tsis tu ncua rau ib xyoos nrog cov dej ntws zoo ruaj khov ua tau raws li qhov tseem ceeb tswj cheeb tsam txwv ntawm * DB13/2795-2018* (Quasi-Class IV tus qauv dej saum npoo av).
② Raws li qhov sib txawv ntawm ntau-theem A / O txheej txheem, tswj qhov siab tshaj plaws DO thaum kawg ntawm BIOLAK aeration cheeb tsam ntawm 0.5-1.0 mg / L ua rau TN tshem tawm tus nqi ntawm 24.0% hauv cheeb tsam BIOLAK thiab 11.3% hauv lub tank sedimentation. Qhov no ua tiav ib txhij nitrification- denitrification thiab endogenous carbon qhov chaw denitrification, ua kom pom qhov muaj peev xwm tshem tawm nitrogen tseem ceeb.
③ Tus nqi ua haujlwm ncaj qha rau cov txheej txheem BIOLAK yog 0.698 CNY / m³. Kev ntsuas kev ua haujlwm kom zoo, suav nrog cov txheej txheem kev soj ntsuam cov ntaub ntawv thiab teeb tsa lub hom phiaj kev tswj hwm sab hauv, tuaj yeem muab cov ntaub ntawv qhia txog kev ua haujlwm zoo thiab ua tiav lub zog / nqi txuag hauv cov chaw kho dej khib nyiab zoo sib xws.