喬 瑋,任征然,李晨艷,熊林鵬,李玉友,董仁杰,4
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自攪拌厭氧折流板反應(yīng)器連續(xù)處理豬場廢水的效果
喬 瑋1,2,任征然1,2,李晨艷1,2,熊林鵬1,2,李玉友3,董仁杰1,2,4※
(1. 中國農(nóng)業(yè)大學工學院,北京 100083; 2. 國家能源生物燃氣高效制備及綜合利用技術(shù)研發(fā)(試驗)中心,北京 100083; 3. 日本東北大學土木與環(huán)境工程系環(huán)境保全研究室,仙臺 980-8579; 4. 中國農(nóng)業(yè)大學煙臺研究院,煙臺 264670)
該研究以豬場廢水為處理對象,采用自攪拌厭氧折流板反應(yīng)器(self-agitation anaerobic baffled reactor,SaABR)開展200 d的連續(xù)中溫厭氧消化試驗,考察在水力停留時間(hydraulic retention time,HRT)3、2、1和0.5 d梯度縮短的過程中,SaABR截留微生物的效果以及反應(yīng)器的產(chǎn)氣性能、穩(wěn)定性和污泥比產(chǎn)甲烷活性(specific methanogenic activity,SMA)。同時,該研究還開展了全混式反應(yīng)器(completely stirred tank reactor,CSTR)78 d的連續(xù)對比試驗。試驗發(fā)現(xiàn),SaABR具有良好的截留微生物的作用,在HRT 3 d時SaABR第1至第4取樣口污泥揮發(fā)性固體(volatile solid,VS)濃度分別為10.2、4.1、44.2和2.5 g/L,而CSTR污泥VS質(zhì)量濃度僅為2.6 g/L。較高的微生物量顯著提高了有機物的降解率并降低了出水的有機酸濃度。隨著HRT的縮短,SaABR的降解率也呈現(xiàn)下降。在HRT 1 d時,SaABR的單位VS產(chǎn)甲烷率為0.43 L/g,即使在HRT 縮短到0.5 d時,仍然可實現(xiàn)穩(wěn)定的發(fā)酵產(chǎn)氣(單位VS產(chǎn)甲烷率為0.24 L/g),而CSTR反應(yīng)器由于微生物洗出不能在HRT 1 d時連續(xù)產(chǎn)氣。該研究的結(jié)果顯示,SaABR反應(yīng)器所具有截留微生物的良好特性,為養(yǎng)殖糞水的處理提供參考。
廢水;發(fā)酵;厭氧折流板反應(yīng)器;自攪拌
養(yǎng)豬業(yè)是中國養(yǎng)殖業(yè)中的重要產(chǎn)業(yè)之一,2016年全國肉豬出欄頭數(shù)為68 502萬頭[1]。據(jù)統(tǒng)計,一個年出欄萬頭的規(guī)模化豬場年排泄糞尿量為400萬t,若采用水沖清糞的方式,則豬場廢水年排量達到550多萬t[2]。豬場廢水COD 質(zhì)量濃度高達6.9~18.1 g/L[3-5],若不能有效處理,將會對環(huán)境造成嚴重的危害。厭氧消化處理豬場廢水在降解有機物的同時產(chǎn)生沼氣[6],是一種經(jīng)濟有效的廢水處理方法。
在眾多厭氧反應(yīng)器中,厭氧折流板反應(yīng)器(anaerobic baffled reactor,ABR)能夠分離水解酸化和產(chǎn)甲烷階段,反應(yīng)器具有兩相系統(tǒng)的優(yōu)點,同時能夠截留微生物,大幅度的縮短水力停留時間(HRT)[7]。然而,折流板反應(yīng)器沒有攪拌系統(tǒng),反應(yīng)器內(nèi)微生物和有機物不能很好的混合接觸,傳質(zhì)較差[8]。為強化反應(yīng)器的混合和傳質(zhì),研究者們在ABR內(nèi)部設(shè)置可實現(xiàn)反應(yīng)器氣體循環(huán)的U型管,使反應(yīng)器可以實現(xiàn)無動力攪拌[9-11]。這種自攪拌厭氧折流板反應(yīng)器(self-agitation anaerobic baffled reactor,SaABR)已在餐廚垃圾的厭氧處理中被發(fā)現(xiàn)有良好的性能[12-13]。目前,關(guān)于SaABR在養(yǎng)殖廢水的厭氧處理的研究還鮮有報道。
為此,本研究開展SaABR處理豬場糞水的連續(xù)試驗,考察反應(yīng)器連續(xù)運行下逐級縮短HRT下的性能。為研究SaABR截留微生物的作用,采用與全混式反應(yīng)器(completely stirred tank reactor,CSTR)進行比較。本研究結(jié)果將為SaABR反應(yīng)器處理養(yǎng)殖廢水的研究和應(yīng)用提供有意義的借鑒。
豬場廢水取自北京市北郎中種豬場,取回后過40目篩去除大顆粒和樹葉等雜質(zhì)后備用;接種污泥取自該養(yǎng)殖場運行良好的豬糞中溫厭氧發(fā)酵罐新鮮出料。豬場廢水和接種污泥的基本性質(zhì)如表1所示。
SaABR反應(yīng)器結(jié)構(gòu)由日本東北大學環(huán)境保全研究室設(shè)計,反應(yīng)器的運行方案參考該試驗室以往研究發(fā)表的論文[9-12]。試驗裝置如圖1所示,圖1a為SaABR裝置系統(tǒng),圖1b為CSTR裝置系統(tǒng)。SaABR系統(tǒng)主要包括基質(zhì)罐和發(fā)酵罐兩部分,發(fā)酵罐總?cè)莘e16 L,有效容積10 L。SaABR從左至右設(shè)置有4個隔室,第1隔室和第2隔室之間設(shè)置1個U形管,第2隔室上部完全密封,產(chǎn)生的沼氣儲存在第1隔室并將第1隔室液面壓低,當液面低于U形管底部時迅速完成一次攪拌;第2到第4隔室上方連通,產(chǎn)生的沼氣可以直接排出后經(jīng)氣袋收集。該反應(yīng)器設(shè)有4個取樣口,從左到右為取樣口1至取樣口4(如圖1a所示)。進、出料口與蠕動泵(申辰BT100N)連接,通過定時器每天自動進出料,HRT為5和3 d時每天進出料2次,HRT為2 d時每天進出料4次,HRT為1和0.5 d時每天進出料8次。CSTR總?cè)莘e為3 L,有效容積為2 L,HRT為5和3 d時該反應(yīng)器每天進出料1次,HRT為2 d時每天進出料2次,HRT為1 d時每天進出料4次。2個反應(yīng)器浸置于(37±1)℃恒溫水箱中。產(chǎn)生的沼氣使用氣袋收集。反應(yīng)器啟動期HRT均為5 d,反應(yīng)器的運行方案如表2和表3所示。
表1 豬場廢水與接種污泥的基本性質(zhì)
注:TS:總固體;VS:揮發(fā)性固體;SS:懸浮固體;VSS:揮發(fā)性懸浮固體;TCOD:總化學需氧量;/:未檢測。
Note: TS: Total solid; VS: Volatile solid; SS: Suspended solids; VSS: Volatile suspended solid; TCOD: Total chemical oxygen demand; /: No detect.
圖1 SaABR和CSTR試驗裝置
表2 SaABR運行方案
表3 CSTR運行方案
TS,VS,SS和VSS采用烘干法測定[14];COD采用重鉻酸鉀法[14];堿度采用滴定法[14];氨氮采用水楊酸-次氯酸鹽光度法[15]。pH值采用玻璃電極(Orion 5-Star pH)pH計測定。VFAs采用島津GC-2010Plus氣相色譜儀測定,采用30 m ×0.25 mm ×0.25m 的毛細柱 Rtx-wax色譜柱和FID檢測器,載氣(氮氣)分壓為0.4 MPa,流速40 mL/min,氫氣流速為20~30 mL/min,進樣口、色譜柱和檢測口溫度分別為230、60和250 ℃。沼氣成分(N2、CH4與CO2)采用島津GC-8A氣相色譜儀測定,色譜柱采用10 m×2 mm不銹鋼的,載氣(氫氣)分壓為0.38 MPa,流速為20~30 mL/min,進樣口、色譜柱和檢測口溫度分別為120、50和120 ℃。每3 d取SaABR和CSTR反應(yīng)器出料測試各項指標。沼氣量采用濕式氣體流量計(LML-1)測量。
在反應(yīng)器穩(wěn)定運行3個HRT后,開始進行產(chǎn)甲烷活性試驗(specific methanogenic activity,SMA)[16]。每個血清瓶中加入90 mL營養(yǎng)液[17]并置于水浴鍋中預加熱至37 ℃,然后向血清瓶中加入10 mL從SaABR各取樣口取出的污泥;再向血清瓶中加入1 mL質(zhì)量濃度為240 g/L的乙酸鈉溶液,血清瓶中的乙酸質(zhì)量濃度為2 000 mg/L。立即向血清瓶中充入氮氣30 s排出空氣,蓋上硅膠塞,用鋁蓋密封。每組試驗設(shè)置2個平行。根據(jù)產(chǎn)氣量每1~3 d用玻璃注射器測沼氣產(chǎn)量,并分析沼氣成分。實際的SMA通過將線性甲烷積累速率的初始斜率除以血清瓶中加入的揮發(fā)性固體來計算[18]。
SaABR反應(yīng)器的運行性能如圖2和圖3所示,CSTR反應(yīng)器性能如圖4所示。本試驗的啟動期較長,SaABR反應(yīng)器在第40天時產(chǎn)氣逐漸穩(wěn)定至0.56 L/(L·d),隨著HRT縮短容積產(chǎn)甲烷率逐漸升高,單位VS產(chǎn)氣率逐漸降低(如圖3所示)。在HRT為3和2 d時甲烷容積產(chǎn)氣率分別為0.85和1.14 L/(L·d)。當HRT縮短至1和0.5 d時,甲烷容積產(chǎn)氣率分別達到1.62和1.71 L/(L·d)。
圖2 SaABR連續(xù)運行系統(tǒng)性能
如圖3所示,SaABR在HRT由3 d縮短到0.5 d的過程中,單位VS的甲烷產(chǎn)率分別是0.69、0.58、0.43和0.24 L/g。隨著HRT的縮短有機物降解率呈明顯的降低。本研究啟動HRT為5 d,沒有測試更長HRT下的甲烷產(chǎn)率。有研究報道,折流板反應(yīng)器處理TS質(zhì)量濃度為50 g/L的豬糞在HRT為14 d時VS甲烷率產(chǎn)為0.59 L/g[19],與本研究HRT 3 d時的結(jié)果相近。
圖3 SaABR不同HRT條件下產(chǎn)甲烷情況
據(jù)此推測,在中溫條件下SaABR在較短的HRT下即可取得較好的有機降解效果。CSTR隨著HRT由3 d縮短到2 d,容積產(chǎn)甲烷率從0.25 L/(L·d)提高至0.44 L/(L·d)。在HRT為1 d時CSTR產(chǎn)氣不穩(wěn)定,在運行了14 d后,反應(yīng)器趨近于不產(chǎn)氣。CSTR停止產(chǎn)氣時pH值為7.51,VFAs質(zhì)量濃度為2 022 mg/L,反應(yīng)器未出現(xiàn)酸化現(xiàn)象。這個濃度的VFAs也不會對甲烷菌產(chǎn)生顯著的抑制作用[20]。產(chǎn)甲烷菌的倍增期為25 h[21],倍增期為65 h[22]。有研究發(fā)現(xiàn)HRT短于1 d時,由于大部分產(chǎn)甲烷菌生長緩慢[23],反應(yīng)器內(nèi)微生物會被洗出而導致發(fā)酵失敗[24]。據(jù)此推測HRT為1 d時CSTR內(nèi)的微生物由于停留時間過短而被洗出,導致發(fā)酵失敗。表4對本研究及關(guān)于豬糞厭氧發(fā)酵產(chǎn)氣情況進行了對比。
文獻報道的氨氮抑制濃度差異很大為1 700~14 000 g/L[25],大多數(shù)產(chǎn)甲烷菌最適pH值范圍為6.5~8.2[26],堿度需要在1~5 g/L以下[26]。如圖2e至g和f至h,本研究中SaABR出料氨氮質(zhì)量濃度在474~1 158 mg/L之間波動,CSTR氨氮質(zhì)量濃度在741~1 234 mg/L波動,沒有達到文獻中的抑制濃度。兩反應(yīng)器pH值均在7~8之間波動,在適合產(chǎn)甲烷菌生長范圍內(nèi)。兩反應(yīng)器堿度也在合適范圍內(nèi),均具有一定的緩沖能力。
表4 本研究的結(jié)果與文獻的對比
注:SPAG為懸浮顆粒附著生長反應(yīng)器。
Note: SPAG is suspended particle-attached growth reactor.
如圖2c,當HRT為3、2、1 d時,SaABR出液VFAs質(zhì)量濃度分為143、195和388 mg/L。當HRT為0.5 d時VFAs質(zhì)量濃度達到了1 610 mg/L。CSTR反應(yīng)器中VFAs濃度在HRT為3、2和1 d時VFAs質(zhì)量濃度分別為793、1370和2 022 mg/L(圖4c)。圖5為HTR 3 d時SaABR各取樣口和CSTR出料污泥的VFAs和TS質(zhì)量濃度。SaABR反應(yīng)器從第1至第4取樣口取樣測得VFAs質(zhì)量濃度分別為375、327、64和70 mg/L。SaABR反應(yīng)器內(nèi)污泥大部分被截留在第3隔室,第3取樣口污泥TS質(zhì)量濃度最高為86.2 g/L,VFAs質(zhì)量濃度最低。CSTR污泥TS質(zhì)量濃度僅為5.4 g/L,VFAs質(zhì)量濃度為786 mg/L。
圖5 HRT 3 d時SaABR和CSTR內(nèi)VFAs和TS質(zhì)量濃度
有研究報道,采用SaABR反應(yīng)器處理TS質(zhì)量濃度為99 g/L的餐廚垃圾時,HRT為15 d時取樣測試前3隔室VFAs質(zhì)量濃度逐漸從1 156 mg/L逐漸降低到708 mg/L,第三隔室底部VFAs質(zhì)量濃度降低至239 mg/L[12],與本研究變化趨勢相近。
圖6a至6e別為不同HRT條件下,SaABR反應(yīng)器內(nèi)各取樣口污泥TS和VS濃度,圖6f為CSTR反應(yīng)器不同HRT條件下出料污泥TS和VS濃度以及VS去除率。SaABR反應(yīng)器的取樣口如圖1a所示。SaABR反應(yīng)器內(nèi)污泥分布不均勻。隨著HRT縮短,SaABR下部2個取樣口(第1和第3取樣口)污泥的濃度呈現(xiàn)降低的趨勢,上部2個取樣口(第2和第4取樣口)污泥的濃度呈現(xiàn)上升的趨勢。HRT為5、3、2、1和0.5 d時SaABR污泥的TS平均質(zhì)量濃度分別為34.1、30.1、27.2、23.6和19.7 g/L。這說明HRT的縮短降低了SaABR截留微生物的能力。CSTR反應(yīng)器的VS去除率隨著HRT縮短逐漸降低,HRT為5、3和2 d時VS去除率分別為49.4%、35.7%和33.7%。HRT為1 d時,試驗進行14 d后,CSTR進出料的濃度基本相同,說明微生物被洗出,已經(jīng)沒有微生物降解作用。SaABR相比于CSTR可以有效的截留微生物。
表5為HRT 3 d時SaABR各取樣口污泥在乙酸濃度為2 000 mg/L時的產(chǎn)甲烷活性。SaABR 4個取樣口的污泥SMA分別為116、97、44和85 mL/(g·d)。由于第3取樣口污泥VS濃度較高,為44.2 g/L,大量微生物被截留在第3取樣口,但可提供其降解的VFAs有限,所以其SMA最低僅為44 mL/(g·d)。
圖6 SAABR和CSTR反應(yīng)器內(nèi)污泥TS和VS濃度
表5 HRT 3 d污泥產(chǎn)甲烷活性對比
SaABR具有良好的微生物截留能力,污泥主要分布在第3和第4隔室之間。SaABR在較短HRT條件下有較高的產(chǎn)氣率,HRT 0.5 d時SaABR仍可以正常產(chǎn)氣,單位VS產(chǎn)甲烷率為0.24 L/g,而CSTR在HRT 1 d時由于微生物被洗出而停止產(chǎn)氣。隨著HRT縮短,SaABR內(nèi)污泥濃度逐漸降低,同時有機物降解率逐漸降低,出水VFAs質(zhì)量濃度增加。本研究的結(jié)果顯示,SaABR反應(yīng)器處理豬場廢水可以在較短HRT條件下取得良好的運行效果。
[1] 國家統(tǒng)計局. 中國統(tǒng)計年鑒[J]. 北京:中國統(tǒng)計出版社,2017.
[2] 王景成,楊秋鳳,周佳萍,等. 利用沼氣工程實現(xiàn)規(guī)模養(yǎng)豬業(yè)可持續(xù)、循環(huán)發(fā)展[J]. 飼料工業(yè),2010,31(11):52-55.
[3] 王陽. UASB處理豬場廢水啟動試驗研究[J]. 氣象與環(huán)境學報,2007,23(2):34-37. Wang Yang. Start-up experiment on pig manure wastewater treatment in UASB reactor[J]. Journal of Meteorology and Environment, 2007, 23(2): 34-37. (in Chinese with English abstract)
[4] Sánchez E, Borja R, Travieso L, et al. Effect of influent substrate concentration and hydraulic retention time on the performance of down-flow anaerobic fixed bed reactors treating piggery wastewater in a tropical climate[J]. Process Biochemistry, 2005, 40(2): 817-829.
[5] Rodrigues L D S, Pinto A C A, Dutra J D C F, et al. Swine wastewater treatment using an anaerobic baffled (ARB) and a UASB reactor system[J]. Semina Ciencias Agrarias, 2017, 38(6): 3705.
[6] Sánchez E, Milán Z, Borja R, et al. Piggery waste treatment by anaerobic digestion and nutrient removal by ionic exchange[J]. Resources Conservation & Recycling, 1995, 15(3/4): 235-244.
[7] 周磊,陳朱蕾,廖波,等. 厭氧折流板反應(yīng)器性能研究進展[J]. 工業(yè)水處理,2005,25(6):1-5. Zhou Lei, Chen Zhulei, Liao Bo, et al. Development of the performance researches on the anaerobic baffled reactor[J]. Industrial Water Treatment, 2005, 25(6): 1-5. (in Chinese with English abstract)
[8] Barber W P, Stuckey D C. The use of the anaerobic baffled reactor (ABR) for wastewater treatment: A review[J]. Water Research, 1999, 33(7): 1559-1578.
[9] Qi W K, Hojo T, Li Y Y. Hydraulic characteristics simulation of an innovative self-agitation anaerobic baffled reactor (SaABR)[J]. Bioresour Technol, 2013, 136(3): 94-101.
[10] Qi W K, Li W C, Du J R, et al. Simulation and configuration correlation analysis of the self-agitation anaerobic baffled reactor for treating livestock organic waste[J]. Biochemical Engineering Journal, 2015, 103: 85-92.
[11] Qi W K, Guo Y L, Xue M, et al. Effect of viscosity on the mixing efficiency in a self-agitation anaerobic baffled reactor [J]. Bioprocess & Biosystems Engineering, 2015, 38(5): 905-910.
[12] Kobayashi T, Li Y Y. Performance and characterization of a newly developed self-agitated anaerobic reactor with biological desulfurization[J]. Bioresource Technology, 2011, 102(10): 5580.
[13] 高希釈生ごみを?qū)澫螭趣筏繐w設(shè)置型サイフォン撹拌式リアクターの高溫メタン発酵特性)[J]. 土木學會論文集G(環(huán)境),2017,73(1):11-19.
[14] 賀延齡. 廢水的厭氧生物處理[M]. 北京:中國輕工業(yè)出版社,1998.
[15] 國家環(huán)境保護總局《水和廢水監(jiān)測分析方法》編委會. 水和廢水監(jiān)測分析方法[M]. 第四版. 北京:中國環(huán)境科學出版社,2002.
[16] Wandera S M, Qiao W, Algapani D E, et al. Searching for possibilities to improve the performance of full scale agricultural biogas plants[J]. Renewable Energy, 2018, 116:720-727.
[17] Angelidaki I, Petersen S P, Ahring B K. Effects of lipids on thermophilic anaerobic digestion and reduction of lipid inhibition upon addition of bentonite[J]. Applied Microbiology & Biotechnology, 1990, 33(4): 469-472.
[18] Ahring B K. Methanogenesis in thermophilic biogas reactors[J]. Antonie Van Leeuwenhoek, 1995, 67(1): 91-102.
[19] Boopathy R. Biological treatment of swine waste using anaerobic baffled reactors[J]. Bioresource Technology, 1998, 64(1): 1-6.
[20] 張萬欽. 微量元素添加對餐廚垃圾和雞糞厭氧消化性能的調(diào)控研究[D]. 北京:中國農(nóng)業(yè)大學,2016. Zhang Wanqin. Effect of Elements Addition on the Anaerobic Digestion Performance of Food Waste and Chicken Manure[D]. Beijing: China Agricultural University, 2016. (in Chinese with English abstract)
[21] Bock A K, Prieger-Kraft A, Sch?nheit P. Pyruvate: A novel substrate for growth and methane formation in Methanosarcina barkeri[J]. Archives of Microbiology, 1994, 161(1): 33-46.
[22] Patel G, Sprott G. Methanosaeta concilii gen nov. sp. nov. (Methanothrix concilii) and Methanosaeta thermoacetophila nom. rev. comb. nov[J]. International Journal of Systematic Bacteriology, 1990, 40(1): 79-82.
[23] 公維佳,李文哲,劉建禹. 厭氧消化中的產(chǎn)甲烷菌研究進展[J]. 東北農(nóng)業(yè)大學學報,2006,37(6):838-841. Gong Weijia, Li Wenzhe, Liu Jianyu. Progress of research on methanogens bacteria in anaerobic digestion[J]. Journal of Northeast Agricultural University, 2006, 37(6): 838-841. (in Chinese with English abstract)
[24] Hill D T, Bolte J P. Methane production from low solid concentration liquid swine waste using conventional anaerobic fermentation[J]. Bioresource Technology, 2000, 74(3): 241-247.
[25] Chen Y, Cheng J J, Creamer K S. Inhibition of anaerobic digestion process: A review[J]. Bioresour Technol, 2008, 99(10): 4044-4064. (in Chinese with English abstract)
[26] 野池達野. 甲烷發(fā)酵[M]. 北京:化學工業(yè)出版社,2014.
[27] Hansen K H, Angelidaki I, Ahring B K. Improving thermophilic anaerobic digestion of swine manure[J]. Wat Res, 1999, 33(8): 1805-1810.
[28] 彭朝暉,樊戰(zhàn)輝,孫家賓,等. 攪拌時間和頂空低壓對豬糞產(chǎn)甲烷速率的影響[J]. 中國沼氣,2017,35(6):50-55. Peng Zhaohui, Fan Zhanhui, Sun Jiabin, et al. Effect of stirring duration and digester low headspace pressure on methane production rate of swine manure[J]. China Biogas, 2017, 35(6): 50-55. (in Chinese with English abstract)
[29] Hill D T, Bolte J P. Evaluation of suspended particle attached growth fermenters treating liquid swine waste[J]. Transactions of the ASAE, 1986, 29(6): 1733-1738.
Continuous anaerobic treatment of swine wastewater by using self-agitation anaerobic baffled reactor
Qiao Wei1,2, Ren Zhengran1,2, Li Chenyan1,2, Xiong Linpeng1,2, Li Yuyou3, Dong Renjie1,2,4※
(1.100083; 2.,,(),100083; 3.,,980-8579; 4.,264670)
With the development of pig industry in China, environmental pollution from such development has become more and more serious. One of the most important problems of pig breeding is the wastewater treatment. Swine wastewater is characterized by the high concentrations of organic matters. Anaerobic digestion has been regarded as a promising technology for swine wastewater treatment to remove the high-concentration organic materials. At the same time, renewable energy in the form of biogas was produced through anaerobic degradation. Previous studies have reported that anaerobic baffled reactor (ABR) can achieve good performance in treating swine wastewater. However, due to the absence of agitation system, the mass transfer is an ABR is unsatisfactory. In order to improve the performance of an ABR, the self-agitation anaerobic baffled reactor (SaABR) was proposed. In the SaABR, a U tube was assembled inside the reactor. SaABR is previously studied in the anaerobic treatment. However, fewer its application in treating swine wastewater was found. The current study therefore investigated the performance of a long term operated SaABR in treating swine wastewater. The total and working volume of SaABR in this study were 16 and 10 L, respectively. Anaerobic treatment of swine wastewater for a period of 200-day was continuously conducted. Mesophilic condition was maintained at 37 ℃ while hydraulic retention time (HRT) was gradual shortening from 5, 3, 2, 1, to 0.5 days. The effects of HRT on the biomass retaining, biogas gas production, process stability, and specific methanogenic activity (SMA) was investigated. At the same time, in this study, we also conducted a 78-day continuous experiment by using a parallel continuous stirred tank reactor (CSTR) as control test. The results derived from this study indicated that SaABR significantly retained high biomass concentration. At the HRT 3 d period, the volatile solid (VS) concentration of the first to fourth sampling ports of SaABR was 10.2, 4.1, 44.2 and 2.5 g/L, respectively. The concentration of VS in the CSTR was as low as 2.6 g/L. The higher microbial biomass significantly increased the degradation efficiencies of organic and reduced the VFAs concentration of SaABR effluent. The degradation efficiency of SaABR also decreased with the shortening of HRT. The specific methane yield of the SaABR was 0.43 L/g at the HRT 1 d period. At the HRT 0.5d period stable biogas production can still be achieved. Through the long term experiment, an increase of volumetric gas production rate was observed: 0.85, 1.14, 1.62 and 1.71 L/(L·d) at HRTs 3, 2, 1 and 0.5 days, respectively. Specific methane gas yield decreased from 0.69 to 0.24 L/g when HRT was reduced from 3 to 0.5 d. These values were slightly higher than results of a previous study using ABR treating swine manure at 40 ℃, which reported specific methane yield was 0.59 L/g. The CSTR ceased to produce biogas at HRT 1 d due to the washout of biomass. At HRT 3 d period, the sludge SMA from the first to the fourth sampling port were 116, 97, 44 and 85 mL/(g·d), respectively. Conclusively, the results obtained in this study showed that SaABR had the advantages of retaining high biomass and would be a promising technology for the anaerobic treatment of swine wastewater.
wastewater; fermentation; anaerobic baffled reactor; self-agitation
10.11975/j.issn.1002-6819.2018.20.027
X712
A
1002-6819(2018)-20-0210-06
2010-04-26
2018-08-17
“十三五”國家重點研發(fā)計劃課題(2016YFD0501403)、北京市自然科學基金(6182017)和北京市科技計劃課題(D1611000016003;D1611000016001)
喬 瑋,副教授,博士,博士生導師,主要從事廢水和廢棄物的厭氧生物處理研究。Email:qiaowei@cau.edu.cn
董仁杰,教授,博士,博士生導師,主要從事生物質(zhì)能源與環(huán)境保護方面研究。Email:rjdong@cau.edu.cn
喬 瑋,任征然,李晨艷,熊林鵬,李玉友,董仁杰. 自攪拌厭氧折流板反應(yīng)器連續(xù)處理豬場廢水的效果[J]. 農(nóng)業(yè)工程學報,2018,34(20):210-215. doi:10.11975/j.issn.1002-6819.2018.20.027 http://www.tcsae.org
Qiao Wei, Ren Zhengran, Li Chenyan, Xiong Linpeng, Li Yuyou, Dong Renjie. Continuous anaerobic treatment of swine wastewater by using self-agitation anaerobic baffled reactor[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2018, 34(20): 210-215. (in Chinese with English abstract) doi:10.11975/j.issn.1002-6819.2018.20.027 http://www.tcsae.org