李海鑫,劉秀紅,楊忠啟,劉潤雨,武文君,楊 慶

調(diào)整氣水比優(yōu)化高氨氮廢水BAF一體化脫氮

李海鑫,劉秀紅*,楊忠啟,劉潤雨,武文君,楊 慶

(北京工業(yè)大學(xué),城鎮(zhèn)污水深度處理與資源化利用技術(shù)國家工程實(shí)驗(yàn)室,北京 100124)

為實(shí)現(xiàn)常溫下高氨氮廢水中氮的高效去除,選取8:1、12:1和15:1等3個(gè)氣水比(GWR)條件,考察常溫下曝氣生物濾池(BAF)短程硝化-厭氧氨氧化(ANAMMOX)一體化自養(yǎng)脫氮工藝穩(wěn)定運(yùn)行的性能.研究結(jié)果表明:進(jìn)水氨氮(NH4+-N)濃度為400mg/L、回流比為1:1的條件下,GWR為15:1脫氮效果最好,氨氮去除率(ARE)達(dá)90%以上,總氮(TN)去除負(fù)荷為1.1kgN/(m3·d),去除率達(dá)83%.GWR為15:1時(shí),溶解氧(DO)為2.41~4.22mg/L,進(jìn)水NH4+-N轉(zhuǎn)化為亞硝(NO2--N)量增加,ANAMMOX活性增強(qiáng).對(duì)生物膜進(jìn)行功能菌種實(shí)時(shí)熒光定量PCR(qPCR)分析得出,GWR為15:1時(shí),ANAMMOX和氨氧化菌(AOB)兩者豐度均最高,高達(dá)1012copies/g dry sludge以上,一體化脫氮效果最好.同時(shí),研究表明提高GWR后ANAMMOX反應(yīng)增強(qiáng),而過程中無N2O生成,GWR為15:1時(shí),N2O總釋放量最小,釋放因子為0.0012.

曝氣生物濾池；生物膜；高氨氮廢水；氣水比；分子生物學(xué)；氧化亞氮

高氨氮廢水成分復(fù)雜,處理難度大且成本高.目前,處理高氨氮廢水的實(shí)際工程項(xiàng)目常用工藝類型主要包括SBR[1]、UASBB[2]、UASB-A/O[3]、A/O+ MBR[4]、A/O-CSTR[5]、升流式微氧生物膜反應(yīng)器[6]、A/O+BAF[7]、ABR[8]等.這些處理工藝停留時(shí)間長,占地面積大,流程復(fù)雜并且啟動(dòng)較難.而短程硝化-厭氧氨氧化一體化脫氮工藝流程短、占地面積小、系統(tǒng)操作容易、運(yùn)行費(fèi)用低、低能高效、易啟動(dòng)等優(yōu)勢(shì)成為目前脫氮技術(shù)的研究熱點(diǎn)[9-13].

短程硝化和厭氧氨氧化細(xì)菌均為自養(yǎng)微生物,世代時(shí)間長,因此實(shí)現(xiàn)一體化脫氮工藝需有效防止好氧氨氧化菌和厭氧氨氧化菌的流失.而BAF系統(tǒng)不但能夠有效保留好氧氨氧化菌和厭氧氨氧化菌,而且避免了生物濾池頻繁反沖洗的問題[14-15],但目前BAF穩(wěn)定運(yùn)行一體化脫氮工藝的相關(guān)報(bào)道較少[16].

GWR是一體化自養(yǎng)脫氮系統(tǒng)中影響DO變化的關(guān)鍵參數(shù),而DO是ANAMMOX過程的限制因素.一方面,GWR的研究不僅要考慮脫氮效果,同時(shí)也要考慮能耗問題.有研究表明, GWR為2:1時(shí),TN平均去除率僅為50.02%[17].雖然GWR較低使得能耗降低,但脫氮效果較差.還有研究發(fā)現(xiàn)在一體化工藝中, GWR應(yīng)控制在28:1~40:1,TN去除效率為89.5%[18].雖然較高的GWR能夠有效脫氨,但同時(shí)也會(huì)造成不必要的能源浪費(fèi);另一方面,考慮脫氮效果和能耗的同時(shí)還要注意是否增加對(duì)環(huán)境的污染.污水生物脫氮過程會(huì)造成N2O的釋放,導(dǎo)致N2O釋放量升高的因素包括:低DO[20]、反硝化過程C/N比過低[21]、高亞硝積累率和較短的水力停留時(shí)間等[22-23].

基于上述考慮,本文以模擬高氨氮廢水為研究對(duì)象,采用火山巖作為BAF濾料,常溫條件下,針對(duì)高氨氮廢水短程硝化-厭氧氨氧化一體化自養(yǎng)脫氮工藝的GWR因素進(jìn)行研究,并結(jié)合功能菌群豐度的變化和基于同位素技術(shù)的N2O釋放量及產(chǎn)生途徑的變化分析,研究目的旨在為實(shí)際工程提供最佳運(yùn)行參數(shù)的同時(shí)減少溫室氣體的排放.

1 材料與方法

1.1 試驗(yàn)材料

1.1.1 試驗(yàn)裝置 本研究采用上流式BAF,反應(yīng)器主體由有機(jī)玻璃制成,濾池底部設(shè)置曝氣盤,濾柱直徑14cm,總高196cm,其中濾料層高110cm,有效容積為19.2L,濾柱每隔20cm設(shè)1個(gè)取樣口,共設(shè)有8個(gè)取樣口.試驗(yàn)所用火山巖濾料直徑為3~5mm.采用上向流方式進(jìn)水,濾池部分出水通過回流管回到濾池底部錐形區(qū)域,池底底部裝有反沖裝置.

運(yùn)行參數(shù):進(jìn)水流量50.77L/d,反沖洗周期為16d,采用氣水聯(lián)合反沖洗,反沖洗時(shí)間為15min.通過調(diào)節(jié)轉(zhuǎn)子流量計(jì)改變曝氣量來控制GWR.

1.1.2 試驗(yàn)用水 本研究采用向北京工業(yè)大學(xué)家屬區(qū)生活污水中投加(NH4)2SO4和NaHCO3的方法,模擬高氨氮廢水,其中NH4+-N濃度為400mg/L, COD、堿度和pH值分別為140mg/L、2.14g/L(以CaCO3計(jì)),7.0~8.0.

1.2 試驗(yàn)方法

1.2.1 水質(zhì)分析方法 試驗(yàn)中NH4+-N、NO2--N和NO3--N等分析均按照國家環(huán)境保護(hù)局發(fā)布的標(biāo)準(zhǔn)方法測(cè)定[24].采用DO測(cè)定儀檢測(cè)反應(yīng)過程中DO 的變化情況(德國,WTW3420).采用DNA提取與實(shí)時(shí)熒光定量PCR分析方法分析功能菌群結(jié)構(gòu)[25].

1.2.2 氣態(tài)及溶解態(tài)N2O測(cè)定方法

(1)氣態(tài)N2O(N2OG)測(cè)定:反應(yīng)裝置密閉,所產(chǎn)氣體經(jīng)U型干燥管干燥除水后收集于氣體采樣袋中.采用Agilent7890氣相色譜儀測(cè)定 N2O,所用色譜柱為HP-Plot/分子篩(30m′0.53mm內(nèi)徑′25mm膜),色譜條件為:進(jìn)樣口110℃;爐溫180℃;ECD檢測(cè)器300℃,所有氣體樣品均經(jīng)多次測(cè)定,直至重現(xiàn)性較好為止.

(2)溶解態(tài)N2O(N2OD)測(cè)定:采用上部空間法測(cè)定[26].在密閉條件下,取BAF沿程水樣.為抑制殘余微量微生物的活性,向12mL頂空瓶中加入0.5mL濃度為1000mg/L的HgCl2溶液,然后加入4.5mL經(jīng)0.45mm濾膜過濾后的水樣.將制好的樣品放入恒溫磁力攪拌器中震蕩1h,測(cè)定上部氣體中的N2O濃度,根據(jù)測(cè)得的N2O濃度及亨利定律計(jì)算出溶解態(tài)N2O濃度.N2O產(chǎn)生量(produced)包括試驗(yàn)過程釋放到大氣中的N2O-N(off)和溶解于水中的N2O-N(dis);本試驗(yàn)N2O濃度以處理單位體積污水產(chǎn)生的N2O-N含量表示.N2O-N釋放量和溶解態(tài) N2O-N濃度根據(jù)Noda提供的方法計(jì)算[27],N2O-N產(chǎn)生量按照下式計(jì)算.

produced=off+dis(1)

1.2.3 同位素測(cè)定方法 采用Isoprime100穩(wěn)定同位素質(zhì)譜分析系統(tǒng)對(duì)所集氣體進(jìn)行同位素分析,抽空20ml頂空瓶,立即注入待測(cè)氣體,通過自動(dòng)進(jìn)樣器用約25mL/min的He氣流將待測(cè)樣品吹進(jìn)含燒堿石棉的化學(xué)阱,99.99%的CO2被吸收.N2O和其他空氣組份被捕集在-196℃的冷阱T2中.吹掃300s后,T2自動(dòng)移出液氮罐,并通過六通閥的轉(zhuǎn)換,將被分析組份轉(zhuǎn)移至-196℃的T3冷阱內(nèi),轉(zhuǎn)換閥的另一頭與色譜柱相連接.待T3移出液氮容器即開始進(jìn)行GC分析,之后進(jìn)行質(zhì)譜分析,用99.99%的N2O氣體做參考?xì)?測(cè)定結(jié)果用反硝化法得到的N2O標(biāo)準(zhǔn)氣體校正,即用USGS32、USGS34 和IAEA-N1產(chǎn)生的標(biāo)準(zhǔn)氣體校準(zhǔn)樣品N2O中氮的bulk值和α值,用USGS34,USGS35和IAEA-N1產(chǎn)生的標(biāo)準(zhǔn)氣體校準(zhǔn)氣體N2O中氧的同位素值.最終根據(jù)所得數(shù)據(jù)計(jì)算出15Nbulk、15Nα及SP值.

1.3 試驗(yàn)設(shè)計(jì)

本試驗(yàn)通過調(diào)整GWR優(yōu)化常溫下高氨氮廢水短程硝化-厭氧氨氧化一體化自養(yǎng)脫氮工藝穩(wěn)定性,研究?jī)?nèi)容可分為2個(gè)部分.第1部分:探究改變GWR條件時(shí)一體化系統(tǒng)脫氮效率情況,結(jié)合不同GWR條件下沿程水質(zhì)變化和典型功能菌群豐度變化對(duì)濾池內(nèi)部反應(yīng)機(jī)理進(jìn)行分析.第2部分:探究改變GWR條件時(shí)濾池內(nèi)N2O釋放量的變化情況,結(jié)合N2O產(chǎn)生途徑進(jìn)行分析.

2 結(jié)果與討論

2.1 高氨氮廢水BAF一體化系統(tǒng)脫氮性能

如圖1所示,基于進(jìn)水氨氮濃度為400mg/L, HRT為4h,回流比為1:1的運(yùn)行參數(shù),當(dāng)GWR為8:1時(shí),BAF內(nèi)平均DO濃度為2.72mg/L,出水NH4+-N濃度為64.78mg/L,ARE為84%,一體化脫氮效果穩(wěn)定.增加GWR至12:1時(shí),出水NH4+-N濃度為66.79mg/L,ARE為83%.氨氮去除效果無明顯變化.第29d再次升高GWR為15:1,BAF內(nèi)平均DO濃度升至3.32mg/L,DO充足,出水NH4+-N濃度降為40.671mg/L,NH4+-N去除率上升至90%,系統(tǒng)內(nèi)NH4+-N轉(zhuǎn)化量增加,為ANAMMOX提供足夠的底物使得反應(yīng)增強(qiáng).

圖1 不同GWR條件下,系統(tǒng)內(nèi)NH4+-N、TN去除情況

當(dāng)GWR為8:1時(shí),出水TN濃度為89.43mg/L, TN去除率為77%.GWR升至12:1時(shí),出水TN濃度為82.16mg/L,TN去除率為79%.再次提高GWR為15:1時(shí),出水TN濃度降至65.5mg/L,TN去除率升高至83%,TN去除負(fù)荷達(dá)到1.1kgN/(m3·d),一體化脫氮效率明顯提高.有研究發(fā)現(xiàn)上向流濾池CANON反應(yīng)器中, GWR高于15:1時(shí)脫氮效果較高,TN去除率為75%,TN去除負(fù)荷為1.1kg/ (m3·d)[28].但在本研究中,當(dāng)系統(tǒng)內(nèi)GWR為15:1時(shí),TN去除率已穩(wěn)定達(dá)到80%以上,TN去除負(fù)荷也已經(jīng)高達(dá)1.1kg/(m3·d),因此無需再提高GWR運(yùn)行造成不必要的能源浪費(fèi).

2.2 一體化脫氮效果分析

2.2.1 提高氣水比促進(jìn)沿程污染物降解速率加快 如圖2所示,NH4+-N降解因GWR增大而呈現(xiàn)出不同規(guī)律.待GWR為8:1條件下穩(wěn)定運(yùn)行后,增加GWR為12:1時(shí),濾層0.15m處,游離氨(FA)濃度為38.89mg/L時(shí)并未對(duì)一體化系統(tǒng)內(nèi)AOB產(chǎn)生抑制,NH4+-N降低了160mg/L,層高0.75m~1.15m處由于DO濃度較小,硝化作用較弱,因此NH4+-N下降趨勢(shì)較緩,同時(shí)濾池沿程N(yùn)O3--N產(chǎn)生速率較緩,由于COD濃度較高,ANAMMOX菌競(jìng)爭(zhēng)NO2--N的能力弱于反硝化菌,反硝化能力增強(qiáng),ANAMMOX反應(yīng)較弱.

圖2 不同GWR條件下生物濾池沿程水質(zhì)變化

當(dāng)再次提高GWR為15:1時(shí),水中DO濃度較高, NH4+-N降解速率較快,池體內(nèi)NH4+-N濃度下降趨勢(shì)較明顯,層高0.15~0.35、0.55~0.95和1.35~1.55m處,降解速率是GWR為8:1時(shí)的1.5倍以上.而0.95~ 1.15m處近3倍,NH4+-N處理效果較好.層高0~ 0.35m處,硝態(tài)氮(NO3--N)濃度明顯增加,這是由于系統(tǒng)內(nèi)DO較高,硝化過程中產(chǎn)生NO2--N充足,從而使ANAMMOX反應(yīng)增強(qiáng).

2.2.2 提高GWR使得厭氧氨氧化活性增強(qiáng) 由表1可知,當(dāng)GWR由8:1提高到12:1時(shí),由于供氧量依舊不足使得NH4+-N未充分轉(zhuǎn)化為NO2--N,脫氮效果無明顯增加.再次升高GWR為15:1時(shí),BAF內(nèi)DO濃度升高,水力沖刷作用加強(qiáng),加快生物膜的更新速度,使生物膜對(duì)氧的利用率增加[29],硝化作用增強(qiáng),進(jìn)水NH4+-N轉(zhuǎn)化為NO2--N量增加.ANAMMOX反應(yīng)底物充足,ANAMMOX反應(yīng)強(qiáng)化導(dǎo)致一體化脫氮效率提高.

表1 不同GWR條件下污染物平均去除情況

注:①反應(yīng)器底部進(jìn)水混合處的DO濃度; ②表示曝氣生物濾池去除系統(tǒng)內(nèi)75%TN時(shí)的濾層深度.

提高GWR為15:1后,濾池內(nèi)部DO濃度較高,平均在2.41mg/L~4.22mg/L之間,濾池濾層0.95m處即能處理75%的總氮.說明本系統(tǒng)在較高的DO條件下,短程硝化更加穩(wěn)定,同時(shí)本生物膜系統(tǒng)內(nèi)ANAMMOX菌種對(duì)于高DO有一定的承受力,短程硝化為ANAMMOX反應(yīng)提供了充足的NO2--N, ANAMMOX反應(yīng)增強(qiáng)從而使一體化效果得到增強(qiáng).表中ΔNH4+-N/ΔNO3--N均大于理論值3.85,說明TN通過多種途徑去除,結(jié)合前面沿程水質(zhì)情況可知包括ANAMMOX、反硝化和N2O釋放等途徑.

2.2.3 提高GWR使得生物膜系統(tǒng)內(nèi)有利菌群豐度增加 由于一體化濾池中短程硝化反應(yīng)和ANAMMOX反應(yīng)同時(shí)進(jìn)行,同時(shí)還有反硝化反應(yīng)的發(fā)生,池體內(nèi)生物膜組成較復(fù)雜,因此本文在不同GWR條件下針對(duì)濾池內(nèi)部生物膜進(jìn)行功能菌種qPCR定量分析.

圖3 不同GWR條件下生物濾池上部菌群豐度變化

如圖3所示,不同GWR條件下濾池菌種豐度存在一定變化,AOB菌種豐度隨GWR增大而升高,從(1.32×1011±1.67×1010)copies/g dry sludge升至(1.86× 1011±2.50×1010)copies/g dry sludge.氣水比為15:1時(shí),ANAMMOX菌種數(shù)量顯著升高,達(dá)1012copies/g dry sludge以上,說明本系統(tǒng)內(nèi)一定存在短程硝化和ANAMMOX反應(yīng).

濾池下部生物膜功能菌種qPCR定量分析結(jié)果如圖4所示,濾池全菌(ALL)、氨氧化古菌(AOA)和亞硝酸鹽氧化菌(NOB)隨GWR升高呈顯著降低的趨勢(shì),提高GWR至15:1時(shí),菌種豐度分別為(1.53× 1015±9.43×1013)copies/g dry sludge、(1.66×107±1.20× 106)copies/g dry sludge和(1.56×108±1.97×107) copies/g dry sludge. GWR增加, DO較高,而高DO可能不利于AOA的生存[30].濾池AOB菌種變化很小,而NOB菌種豐度明顯降低,可能是受較高DO影響,說明在高DO條件下反而不利于NOB的繁殖,更易維持穩(wěn)定的短程硝化.濾池中反硝化菌(nirK和nirS)豐度也隨GWR增大而降低,因?yàn)樵龃驡WR后池體內(nèi)DO濃度升高,生物膜內(nèi)部厭氧區(qū)減小,不利于反硝化菌生長.而反硝化菌(nosZ)在GWR12:1時(shí)豐度最小.

對(duì)比改變GWR條件時(shí)濾池上部和下部菌種豐度變化情況得出,濾池各個(gè)菌種豐度變化不大,群落結(jié)構(gòu)較穩(wěn)定.由于濾池微生物菌種較豐富, GWR的變化并未對(duì)其造成較大影響,因此濾池成熟的生物膜可以抵抗一定水力負(fù)荷的沖擊.不同GWR條件下濾池菌種豐度定量分析結(jié)果與相應(yīng)條件下池體出水水質(zhì)分析情況一致,在GWR為15:1時(shí), ANAMMOX和AOB兩者豐度均最高,因此出水水質(zhì)最好.

2.3 優(yōu)化一體化系統(tǒng)內(nèi)N2O的釋放

一體化系統(tǒng)脫氮過程中會(huì)產(chǎn)生N2O,主要通過羥胺(NH2OH)氧化、硝化細(xì)菌反硝化和反硝化等3種途徑產(chǎn)生,而N2O的釋放會(huì)造成環(huán)境的破壞,因此優(yōu)化一體化系統(tǒng)脫氮效果的同時(shí)需要減少N2O的釋放,為此研究不同GWR條件下N2O的釋放量和產(chǎn)生途徑,通過調(diào)整GWR來實(shí)現(xiàn)N2O的減排.

圖5 不同GWR條件下生物濾池N2O釋放量

2.3.1 提高GWR降低N2O總釋放量 在增強(qiáng)GWR條件時(shí),對(duì)BAF一體化自養(yǎng)脫氮工藝內(nèi)N2O含量進(jìn)行檢測(cè),如圖5所示.當(dāng)GWR由8:1增加到15:1時(shí),N2OD含量隨GWR增大而減少,由0.31N mg/L降至0.13N mg/L.N2OG釋放量卻隨GWR增加而增加,由0.16N mg/L增至0.25N mg/L.系統(tǒng)內(nèi)N2O總量隨GWR增加而降低,從0.47N mg/L降至0.38N mg/L.通過N2O釋放因子的計(jì)算得出[31],3種GWR條件下N2O釋放因子分別為0.0015、0.0013和0.00085.因此當(dāng)GWR為15:1時(shí),系統(tǒng)內(nèi)N2O的釋放量最低.

2.3.2 不同GWR 條件下N2O產(chǎn)生途徑 在GWR為8:1、12:1和15:1條件下,對(duì)一體化自養(yǎng)脫氮工藝中N2O產(chǎn)生途徑進(jìn)行研究.分別對(duì)BAF中收集的氣體進(jìn)行穩(wěn)定同位素測(cè)定,得到N2O氣體的SP值,從而判斷反應(yīng)過程N(yùn)2O產(chǎn)生途徑,結(jié)果如表2所示.

表2 不同GWR條件下長期運(yùn)行過程同位素測(cè)定結(jié)果

已有研究結(jié)果表明[32],假定NH2OH氧化過程生成N2O氣體的SP值(SPNN)平均為28.5‰,硝化細(xì)菌反硝化過程生成N2O氣體的SP值(SPND)平均為-2‰,這2種反應(yīng)生成的N2O占總生成量的比例分別為NN和ND,盡管存在生成N2的未知反應(yīng),仍可通過下式計(jì)算兩者所占比例[33]:

ND=(1?NN)=(SPTOT?SPNN)/(SPND-SPNN) (2)

由表2可知,3種GWR條件下,大部分N2O是通過硝化細(xì)菌反硝化過程產(chǎn)生的.當(dāng)GWR較低時(shí),80%左右的N2O是由硝化細(xì)菌反硝化過程生成的.由于生物膜內(nèi)部存在厭氧區(qū)域,一些好氧硝化菌會(huì)在DO較低的條件下將NO2--N還原為N2O,即硝化細(xì)菌的反硝化作用.但提高GWR時(shí),池體內(nèi)DO濃度升高,硝化細(xì)菌活性增強(qiáng),通過NH2OH氧化過程生成的N2O增加.當(dāng)GWR為8:1和12:1時(shí),DO不足,由于反硝化作用導(dǎo)致N2O生成量增加,同時(shí)濾池底部氧化亞氮還原酶基因型反硝化菌種在GWR為12:1時(shí)豐度最小,只有小部份的N2O被還原.當(dāng)再次提高GWR為15:1時(shí),除NH2OH氧化生成的N2O外,由于反硝化作用減弱,而ANAMMOX反應(yīng)增強(qiáng)但過程中無N2O產(chǎn)生,故總量減小,與出水水質(zhì)分析一致.

綜合考慮脫氮效果、N2O釋放量和能量消耗等問題,本研究常溫下BAF高氨氮廢水一體化自養(yǎng)脫氮工藝的最佳GWR為15:1,TN去除率為83%,TN去除負(fù)荷達(dá)到1.1kgN/(m3·d),N2O釋放因子為0.0012.

3 結(jié)論

3.1 常溫下BAF高氨氮廢水一體化自養(yǎng)脫氮,當(dāng)系統(tǒng)內(nèi)進(jìn)水氨氮濃度為400mg/L,回流比為1:1條件下,GWR為8:1和12:1時(shí),一體化系統(tǒng)中TN去除率為分別為77%和79%.提高GWR為15:1時(shí),TN去除率升至83%,一體化脫氮效率明顯提高,TN去除負(fù)荷達(dá)到1.1kgN/(m3·d).

3.2 GWR為15:1時(shí),沿程污染物降解速率較快,濾池層高0.95~1.15m處氨氮降解速率是8:1時(shí)的2.5倍以上; DO在2.41~4.22mg/L之間,NO2--N生成量增加,ANAMMOX活性增強(qiáng);系統(tǒng)內(nèi)有利菌群豐度增加,ANAMMOX和AOB兩者豐度均最高, ANAMMOX菌種隨GWR增加從(4.07×1011± 5.11×109)copies/g dry sludge升至(1.14×1012±6.45× 109)copies/g dry sludge.

3.3 系統(tǒng)內(nèi)N2O總釋放量隨GWR增加而降低,GWR為15:1時(shí),ANAMMOX反應(yīng)增強(qiáng)而過程中無N2O產(chǎn)生,N2O總釋放量最小,釋放因子為0.0012.

[1] Guerrero L, Montalvo S, Huili?ir C, et al. Simultaneous nitrification– denitrification of wastewater: effect of zeolite as a support in sequential batch reactor with step-feed strategy [J]. International Journal of Environmental Science and Technology, 2016,13(10): 2325-2338.

[2] 李亞峰,馬晨曦,張 馳.UASBB厭氧氨氧化反應(yīng)器處理污泥脫水液的影響因素研究[J].環(huán)境科學(xué), 2014,35(8):3044-3051. Li Y F, Ma C X, Zhang C. Influencing Factors of Sludge Liquor Treatment in UASBB [J]. Environmental Science, 2014,35(8):3044- 3051.

[3] 孫洪偉,彭永臻,時(shí)曉寧,等.UASB-A/O工藝處理垃圾滲濾液短程生物脫氮的實(shí)現(xiàn)[J]. 中國環(huán)境科學(xué), 2009,29(10):1059-1064. Sun H W, Peng Y Z, Shi X Y, et al. Achieving nitrogen removal from landfill leachate via UASB-A/O process [J]. China Environmental Science, 2009,29(10):1059-1064.

[4] 趙 晴,梁俊宇,呂 慧,等.AO-MBR工藝短程硝化反硝化處理垃圾滲濾液中試研究 [J]. 北京工業(yè)大學(xué)學(xué)報(bào), 2018,44(1):45-49. Zhao Q, Liang J Y, Lv H, et al. Pilot-scale Study on nitritation– Denitritation of Landfill Leachate by an AO-MBR Process [J].Journal of Beijing University of Technology, 2018,44(1):45-49.

[5] 張 亮,王淑瑩,張樹軍,等.高氨氮污泥脫水液短程硝化反硝化的啟動(dòng)及穩(wěn)定[J]. 環(huán)境工程學(xué)報(bào), 2012,6(4):1064-1068. Zhang L, Wang S Y, Zhang S J, et al. Start up and maintenance of partial nitrification-denitrification of high strength ammonia sludge dewatering water [J]. Chinese Journal of Environmental Engineering, 2012,6(4):1064-1068.

[6] 王 成,孟 佳,李玖齡,等.升流式微氧生物膜反應(yīng)器處理高氨氮低C/N比養(yǎng)豬廢水的效能[J].化工學(xué)報(bào), 2016,67(9):3895-3901. Wang C, Meng J, Li J L, et al. Pollutant removal efficiency in upflow microaerobic biofilm reactor treating manure-free piggery wastewater with low COD/TN ratio and high NH4+-N [J]. CIESC Journal, 2016,67(9):3895-3901.

[7] 俞 彬,陳廣升,王玉慧,等.A/O+BAF工藝處理高氨氮煤化工廢水[J]. 中國給水排水, 2013,29(6):81-83+88. Yu B, Chen G S, Wang Y H, et al. A/O+BAF Process for Treatment of Coal Chemical Wastewater with High Ammonia Nitrogen [J]. CHINA WATER & WASTEWATER, 2013,29(6):81- 83+88.

[8] 吳 鵬,張?jiān)姺f,宋吟玲,等.ABR工藝ANAMMOX耦合短程硝化協(xié)同脫氮處理城市污水[J]. 環(huán)境科學(xué), 2016,37(8):3108-3113. WU P, ZHANG S Y, SONG Y L, et al. Nitrogen Removal of Municipal Wastewater by ANAMMOX Coupled Shortcut Nitrification in Anaerobic Baffled Reactor [J]. Environmental Science, 2016, 37(8):3108-3113.

[9] Lackner S, Gilbert E M, Vlaeminck S E, et al. Full-scale partial nitritation/Anammox experiences – An application survey [J]. Water Research, 2014,55:292-303.

[10] Gao D, Lu J, Liang H. Simultaneous energy recovery and autotrophic nitrogen removal from sewage at moderately low temperatures [J]. Applied Microbiology and Biotechnology, 2014,98(6):2637-2645.

[11] Wen X, Zhou J, Wang J, et al. Effects of dissolved oxygen on microbial community of single-stage autotrophic nitrogen removal system treating simulating mature landfill leachate [J]. Bioresource Technology, 2016,218:962-968.

[12] Vo T T, Nguyen T P. Nitrogen removal from old landfill leachate with SNAP technology using biofix as a biomass carrier [J]. Journal of Bioscience and Bioengineering, 2016,122(2):188-195.

[13] Daverey A, Su S, Huang Y,. Partial nitrification and Anammox process: A method for high strength optoelectronic industrial wastewater treatment [J]. Water Research, 2013,47(9):2929-2937.

[14] Liu X, Wang H, Long F, et al. Optimizing and real-time control of biofilm formation, growth and renewal in denitrifying biofilter [J]. Bioresource Technology, 2016,209:326-332.

[15] 楊 慶,谷鵬超,劉秀紅,等.兩種典型濾料厭氧氨氧化效果與工藝運(yùn)行優(yōu)化[J]. 化工學(xué)報(bào), 2015,66(1):455-463. Yang Q, Gu P C, Liu X H, et al. Comparison of performance and optimizing process for two typical filter medias of ANAMMOX biofilters [J]. CIESC Journal, 2015,66(1):455-463.

[16] 楊 慶,周 桐,劉秀紅,等.常溫下接種回流污泥實(shí)現(xiàn)BAF一體化自養(yǎng)脫氮工藝[J]. 化工學(xué)報(bào), 2017,68(5):2081-2088. Yang Q, Zhou T, Liu X H, et al. Implementation of integrated autotrophic nitrogen removal system at normal temperature by returned sludge [J]. CIESC Journal, 2017,68(5):2081-2088.

[17] 楊長生.氣水比對(duì)曝氣生物濾池SND的影響[J].工業(yè)水處理, 2011,31(8):63-66. YANG C S. Influence of air/water ratio on the performance of SND in BAF [J]. Industrial Water Treatment, 2011,(8):63-66.

[18] Liang Y, Li D, Zhang X, et al. Performance and influence factors of completely autotrophic nitrogen removal over nitrite(CANON) process in a biofilter packed with volcanic rocks [J]. Environmental Technology, 2015,36(8):946-953.

[19] 路俊玲,陳慧萍,肖 琳.溫度和氨氮濃度對(duì)水體N2O釋放的影響 [J]. 中國環(huán)境科學(xué), 2019,39(1):330-335. Lu J L, Chen H P, Xiao L. Coupling effect of temperature and ammonia on N2O emission in surface water [J].China Environmental Science, 2019,39(1):330-335.

[20] Rathnayake L, Ishii S, Satoh H. Effects of dissolved oxygen and pH on nitrous oxide production rates in autotrophic partial nitrification granules [J]. Bioresource Technology, 2015,197:15-22.

[21] Itokawa H, Hanaki K, Matsuo T. Nitrous oxide production in high-loading biological nitrogen removal process under low COD/N ratio condition [J]. Water Research, 2001,35(3):657-664.

[22] Qing Y, Xiuhong L, Chengyao P, et al. N2O Production during Nitrogen Removal via Nitrite from Domestic Wastewater: Main Sources and Control Method [J]. Environmental Science & Technology, 2009,43(24):9400-9406.

[23] Noda N, Kaneko N, Mikami M, et al. Effects of SRT and DO on N2O reductase activity in an anoxic-oxic activated sludge system [J]. Water Science & Technology, 2003,48(11/12):363-370.

[24] 張鈴敏,常青龍,史 勤,等.CANON 工藝短程硝化恢復(fù)調(diào)控及微生物種群結(jié)構(gòu)變化[J]. 中國環(huán)境科學(xué), 2019,39(6):2354-2360. Zhang L M, Chang Q L, Shi Q,et al.The recovery regulation of a CANON system and variations in the microbial community [J]. China Environmental Science, 2019,39(6):2354-2360.

[25] Zhou X, Liu X, Huang S, et al. Total inorganic nitrogen removal during the partial/complete nitrification for treating domestic wastewater: Removal pathways and Main influencing factors [J]. Bioresource Technology, 2018,256:285-294.

[26] Yang Q, Liu X, Peng C, et al. N2O Production during Nitrogen Removal via Nitrite from Domestic Wastewater: Main Sources and Control Method [J]. Environmental Science & Technology, 2009, 43(24):9400-9406.

[27] Noda N, Kaneko N, Milkami M, et al. Effects of SRT and DO on N2O reductase activity in an anoxic-oxic activated sludge system [J]. Water Science and Technology, 2003,48(11/12):363-370.

[28] 劉 濤,李 冬,曾輝平,等.常溫下CANON反應(yīng)器中功能微生物的沿程分布[J]. 哈爾濱工業(yè)大學(xué)學(xué)報(bào), 2012,44(10):22-27. Liu T, Li D, Zeng H P, et al. Distribution of functional bacteria alone bio-filter of CANON reactor at room temperature [J]. Journal of Harbin Institute of Technology, 2012,44(10):22-27.

[29] Cema G, P?aza E, Trela J,et al. Dissolved oxygen as a factor influencing nitrogen removal rates in a one-stage system with partial nitritation and Anammox process [J]. Water Science & Technology, 2011,64(5):1009-1015.

[30] Park H D, Wells G F, Bae H, et al. Occurrence of Ammonia-Oxidizing Archaea in Wastewater Treatment Plant Bioreactors [J]. Applied and Environmental Microbiology, 2006,72(8):5643-5647.

[31] Hu M P, Chen D J, Dahlgren R A. Modeling nitrous oxide emission from rivers: a global assessment [J].Global Change Biology, 2016,22(11):3566-3582.

[32] Wunderlin P, Lehmann M F, Siegrist H,et al. Isotope Signatures of N2O in a Mixed Microbial Population System: Constraints on N2O Producing Pathways in Wastewater Treatment [J]. Environmental Science & Technology, 2013,47(3):1339-1348.

[33] Frame C H, Casciotti K L. Biogeochemical controls and isotopic signatures of nitrous oxide production by a marine ammonia-oxidizing bacterium [J]. Biogeosciences, 2010,9(7):2695-2709.

Optimization of the integrated nitrogen removal process of high ammonia nitrogen wastewater in BAF by adjusting the gas water ratio.

LI Hai-xin, LIU Xiu-hong*, YANG Zhong-qi, LIU Run-yu, WU Wen-jun, YANG Qing

(National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Techndogy, Beijing University and Technology, Beijing 100124, China)., 2019,39(9)：3807~3813

In order to achieve efficient removal of nitrogen from high ammonia nitrogen wastewater at room temperature, this study selected three gas water ratio conditions, 8:1、12:1 and 15:1 respectively. It investigated the stable operation performance of partial nitrification-ANAMMOX integrated autotrophic nitrogen removal process of biological aerated filter (BAF) at room temperature. The results showed that gas water ratio (GWR) at the optimal operation time was 15:1under the condition of inlet ammonia nitrogen (NH4+-N) concentration of 400mg/L and reflux ratio of 1:1, ammonia nitrogen removal rate (ARE) was over 90%,total nitrogen (TN) removal load was 1.1kgN/(m3·d), and TN removal rate could reach 83%. When the GWR is 15:1,the DO is controlled around 2.41mg/L and 4.22mg/L, the amount of NH4+-N converted into nitrite (NO2--N) in water increased, and the ANAMMOX activity is enhanced. The real-time fluorescence quantitative PCR (QPCR) analysis of functional strains on the biofilm showed that when the GWR was 15:1, both ANAMMOX and AOB had the highest abundance, more than 1012copies/g dry sludge. Therefore, integrated nitrogen removal has the best effect. At the same time, studies have shown that the ANAMMOX reaction is strengthened after increasing the gas water ratio and N2O is not generated in the ANAMMOX process. When the GWR is 15:1, the total release amount of N2O is the smallest, and the release factor is 0.0012.

BAF；biofilm；high ammonia nitrogen wastewater；GWR；molecular biology；N2O

X703.1

A

1000-6923(2019)09-3807-07

李海鑫(1994-),女,黑龍江伊春人,碩士研究生,主要從事污水生物脫氮研究.

2019-02-28

國家自然科學(xué)基金資助項(xiàng)目(51878011);北京市自然科學(xué)基金資助項(xiàng)目(8182012)

* 責(zé)任作者, 副研究員, lxhfei@163.com