微生物燃料電池廢水生物處理技術
1 水污染(ran)現狀(zhuang)與(yu)污水資源化
隨著工(gong)農業生(sheng)產的發展(zhan)和(he)人們生(sheng)活水(shui)(shui)平的提高,水(shui)(shui)污(wu)染(ran)與能(neng)源危(wei)機成為了當(dang)今世界面臨的兩(liang)大難題。目前,仍(reng)廣泛采(cai)用(yong)的是利(li)(li)用(yong)微生(sheng)物(wu)的代謝作用(yong)除去廢(fei)水(shui)(shui)中有機污(wu)染(ran)物(wu),主要包括好(hao)(hao)氧和(he)厭氧生(sheng)物(wu)處(chu)理(li)兩(liang)種(zhong)方(fang)(fang)法(fa)。然(ran)而(er)(er),這兩(liang)種(zhong)方(fang)(fang)法(fa)在實踐應用(yong)中也存在缺點。一方(fang)(fang)面,好(hao)(hao)氧生(sheng)物(wu)處(chu)理(li)需要消耗大量的能(neng)量,運(yun)行費用(yong)高。另一方(fang)(fang)面,傳統的厭氧工(gong)藝雖然(ran)運(yun)行費用(yong)降低,且在處(chu)理(li)過程中可以以甲烷形(xing)式(shi)(shi)獲得額外的生(sheng)物(wu)能(neng),但由(you)于甲烷沒有合(he)理(li)的利(li)(li)用(yong)方(fang)(fang)式(shi)(shi)將(jiang)其(qi)燃燒(shao)掉而(er)(er)無法(fa)實現能(neng)源的回收(shou)。從循(xun)環利(li)(li)用(yong)角度考慮,有機廢(fei)水(shui)(shui)中又包含著一定濃(nong)度的易生(sheng)物(wu)降解(jie)物(wu)質(zhi)和(he)可再生(sheng)利(li)(li)用(yong)物(wu)質(zhi),如果能(neng)夠以某種(zhong)方(fang)(fang)式(shi)(shi)從中回收(shou)能(neng)源和(he)有用(yong)物(wu)質(zhi)則不僅可以減少(shao)廢(fei)水(shui)(shui)處(chu)理(li)的費用(yong),而(er)(er)且可以在一定程度上緩解(jie)當(dang)前面臨的能(neng)源危(wei)機。
2 微生(sheng)物燃料電(dian)池(chi)構造與基本原(yuan)理
微(wei)生(sheng)物(wu)燃料(liao)電(dian)(dian)池(chi)(MFC)是利(li)用微(wei)生(sheng)物(wu)直接(jie)氧(yang)化還原性可生(sheng)物(wu)降解(jie)物(wu)質(zhi),并從中生(sheng)產電(dian)(dian)能的裝(zhuang)置(zhi)。原理與(yu)燃料(liao)電(dian)(dian)池(chi)(FC)相似,但可以(yi)利(li)用比甲醇或氫(qing)更復(fu)雜的燃料(liao)。傳統的微(wei)生(sheng)物(wu)燃料(liao)電(dian)(dian)池(chi)為雙(shuang)室(shi)型,分(fen)別由四個(ge)基本部分(fen)組成(cheng):陽極(ji)(ji)室(shi)、陰極(ji)(ji)室(shi)、質(zhi)子(zi)交換(huan)膜(mo)和電(dian)(dian)解(jie)液(如(ru)圖(tu)1所示)[1]。
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圖1 典型的H型微生物燃料電池結(jie)構示意(yi)圖
Fig.1 Schematic picture of a typical two-chamber MFC
微生(sheng)物(wu)燃(ran)料電(dian)(dian)(dian)池(chi)的(de)(de)(de)(de)(de)(de)基本原(yuan)理是打破常(chang)規的(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)子傳遞(di)鏈的(de)(de)(de)(de)(de)(de)傳遞(di)方向,把產生(sheng)的(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)子引到(dao)(dao)外界(jie),從(cong)中獲取(qu)能(neng)量(liang)。從(cong)另一(yi)個(ge)(ge)角度(du)來說,是把原(yuan)本的(de)(de)(de)(de)(de)(de)氧(yang)(yang)化還原(yuan)反(fan)應(ying)的(de)(de)(de)(de)(de)(de)發生(sheng)區(qu)域擴展到(dao)(dao)細(xi)胞(bao)(bao)以外的(de)(de)(de)(de)(de)(de)外界(jie)環(huan)境,延伸到(dao)(dao)整個(ge)(ge)電(dian)(dian)(dian)池(chi)結構體系中。陽(yang)極(ji)室中的(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)化學活性微生(sheng)物(wu)在(zai)厭氧(yang)(yang)環(huan)境下催化氧(yang)(yang)化電(dian)(dian)(dian)解液中還原(yuan)性有機(ji)物(wu)從(cong)中獲取(qu)能(neng)量(liang)在(zai)陽(yang)電(dian)(dian)(dian)極(ji)上以生(sheng)物(wu)膜的(de)(de)(de)(de)(de)(de)形(xing)(xing)式生(sheng)長,細(xi)胞(bao)(bao)呼(hu)吸過(guo)程中釋放出電(dian)(dian)(dian)子通過(guo)相關(guan)酶(mei)、輔酶(mei)和氧(yang)(yang)化還原(yuan)型媒(mei)介(如(ru)果存(cun)在(zai))傳遞(di)給陽(yang)極(ji),再通過(guo)外電(dian)(dian)(dian)路(lu)循環(huan)到(dao)(dao)達(da)陰(yin)極(ji)形(xing)(xing)成電(dian)(dian)(dian)流。同時,在(zai)反(fan)應(ying)過(guo)程中伴隨電(dian)(dian)(dian)子而產生(sheng)的(de)(de)(de)(de)(de)(de)質子從(cong)陽(yang)極(ji)室穿過(guo)質子交換膜(PEM)到(dao)(dao)達(da)陰(yin)極(ji),并在(zai)陰(yin)極(ji)催化劑(ji)(例如(ru)Pt)存(cun)在(zai)條(tiao)件下與那里的(de)(de)(de)(de)(de)(de)氧(yang)(yang)氣和電(dian)(dian)(dian)子結合(he)生(sheng)成水。為(wei)提高反(fan)應(ying)速(su)率通常(chang)在(zai)陽(yang)極(ji)室攪拌(ban),陰(yin)極(ji)室曝氣。
以葡萄糖作(zuo)為微生物燃料(liao)基(ji)質為例(li):
只要稍微調整(zheng)(zheng)構型或運行(xing)條件,就(jiu)能從MFC中(zhong)以較高的(de)(de)(de)(de)效率產(chan)(chan)氫,而替代產(chan)(chan)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)。具(ju)體(ti)做法為(wei)將陰極封閉,去除氧,并(bing)在(zai)整(zheng)(zheng)個電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)循環(huan)上施加(jia)一個小的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya),氫氣(qi)便能從陰極產(chan)(chan)生(sheng)(sheng)(sheng)。基本原理為(wei),微生(sheng)(sheng)(sheng)物(wu)代謝產(chan)(chan)生(sheng)(sheng)(sheng)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)子(zi)經(jing)過外電(dian)(dian)(dian)(dian)(dian)(dian)(dian)路(lu)循環(huan)后到達陰極后不(bu)再傳遞給氧,而是傳遞給穿過質(zhi)子(zi)交(jiao)換膜的(de)(de)(de)(de)質(zhi)子(zi)。由(you)此(ci)經(jing)過調整(zheng)(zheng)后的(de)(de)(de)(de)MFC可以成為(wei)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)化學(xue)協助(zhu)產(chan)(chan)氫微生(sheng)(sheng)(sheng)物(wu)反(fan)應(ying)器(BEAMR)。電(dian)(dian)(dian)(dian)(dian)(dian)(dian)解水產(chan)(chan)氫由(you)于(yu)其較高的(de)(de)(de)(de)熱(re)(re)力學(xue)吸熱(re)(re)本質(zhi),在(zai)實踐中(zhong)要求在(zai)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極兩端施加(jia)高達1.8 V左右(you)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)。而電(dian)(dian)(dian)(dian)(dian)(dian)(dian)化學(xue)協助(zhu)產(chan)(chan)氫在(zai)熱(re)(re)力學(xue)上為(wei)放(fang)熱(re)(re)反(fan)應(ying),微生(sheng)(sheng)(sheng)物(wu)在(zai)利用(yong)有機物(wu)的(de)(de)(de)(de)同時放(fang)出熱(re)(re)量,并(bing)在(zai)陽極產(chan)(chan)生(sheng)(sheng)(sheng)0.3 V(比標(biao)準(zhun)氫電(dian)(dian)(dian)(dian)(dian)(dian)(dian)極)左右(you)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)。只要再額(e)外施加(jia)0.25 V的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)就(jiu)能在(zai)陰極產(chan)(chan)生(sheng)(sheng)(sheng)氫氣(qi)。理論(lun)上,1 mol的(de)(de)(de)(de)醋酸能產(chan)(chan)生(sheng)(sheng)(sheng)4 mol的(de)(de)(de)(de)氫氣(qi)。但實際中(zhong)由(you)于(yu)能量的(de)(de)(de)(de)損失(shi),1 mol的(de)(de)(de)(de)醋酸只能產(chan)(chan)生(sheng)(sheng)(sheng)2.9 mol的(de)(de)(de)(de)氫氣(qi)。
3 MFC的性能優(you)化
3.1 微(wei)生(sheng)物優化
微(wei)生(sheng)物(wu)細胞膜含(han)有類脂(zhi)或(huo)肽聚糖(tang)等不導(dao)電(dian)(dian)(dian)物(wu)質,電(dian)(dian)(dian)子難以(yi)穿過。因此通(tong)常向微(wei)生(sheng)物(wu)燃料(liao)電(dian)(dian)(dian)池(chi)陽(yang)極室(shi)中(zhong)人工投(tou)加電(dian)(dian)(dian)子介(jie)體(ti)來協(xie)助電(dian)(dian)(dian)子傳遞提(ti)高輸(shu)出(chu)功率。然而(er)這些介(jie)體(ti)具有費(fei)用昂貴、需要定期更換、對微(wei)生(sheng)物(wu)有毒等缺點[2]。目前,通(tong)過純培養方式已經從(cong)微(wei)生(sheng)物(wu)燃料(liao)電(dian)(dian)(dian)池(chi)陽(yang)極室(shi)中(zhong)分離出(chu)多(duo)種在無需外界添(tian)加任何氧化還原介(jie)體(ti)的(de)條(tiao)件下也實現較高電(dian)(dian)(dian)能輸(shu)出(chu)的(de)微(wei)生(sheng)物(wu)。
3.2 反應器構型(xing)優(you)化
雙室(shi)型(xing)(xing)微生物燃料電(dian)(dian)池最(zui)大(da)的缺點是(shi)內(nei)阻大(da)、陰極需要曝氣(qi)而消耗能(neng)量(liang)。最(zui)近開發的一種新型(xing)(xing)單室(shi)型(xing)(xing)微生物燃料電(dian)(dian)池,將質子交換膜(mo)捆綁在鍍有金屬催化(hua)劑的陰極上(shang)并直接暴(bao)露于空(kong)(kong)氣(qi)中(zhong),這樣在被動通風的條件(jian)下(xia),空(kong)(kong)氣(qi)中(zhong)的氧氣(qi)就能(neng)直接迅(xun)速得在電(dian)(dian)極上(shang)反應[3]。單室(shi)型(xing)(xing)微生物燃料電(dian)(dian)池具有以下(xia)優點:降(jiang)低了(le)由陰極超電(dian)(dian)勢導致的內(nei)阻、降(jiang)低了(le)運(yun)行費(fei)用、整體(ti)上(shang)降(jiang)低了(le)反應器體(ti)積、簡化(hua)了(le)設(she)計。
3.3 電化學優化
3.3.1陽極的優化
石(shi)墨(mo)板和石(shi)墨(mo)棒是(shi)陽(yang)極最常(chang)使用的(de)(de)材(cai)料,具有廉(lian)價、容易加工、有確定(ding)的(de)(de)表面(mian)積等(deng)優點。將石(shi)墨(mo)加工成石(shi)墨(mo)氈(zhan)為(wei)微生物的(de)(de)生長(chang)提(ti)供了(le)(le)更大(da)的(de)(de)表面(mian)積從而提(ti)高反應器性能。除此之外(wai)石(shi)墨(mo)還可(ke)以加工為(wei)碳(tan)纖維、碳(tan)布、碳(tan)紙、碳(tan)沫等(deng)形式(shi)。更大(da)的(de)(de)比表面(mian)積可(ke)以通過使用不(bu)同孔徑的(de)(de)網(wang)狀(zhuang)玻璃碳(tan)或(huo)者碳(tan)粒包裹床來實(shi)現。多孔徑減少了(le)(le)由于(yu)生物膜生長(chang)導致孔徑堵塞的(de)(de)問題。
3.3.2陰(yin)極的優化
微生物燃料(liao)電(dian)(dian)(dian)(dian)池(chi)的(de)(de)(de)功(gong)率輸出(chu)與開路條件下陰(yin)陽(yang)兩極(ji)(ji)(ji)(ji)電(dian)(dian)(dian)(dian)勢(shi)(shi)差的(de)(de)(de)平方呈(cheng)正(zheng)比。陽(yang)極(ji)(ji)(ji)(ji)電(dian)(dian)(dian)(dian)勢(shi)(shi)基本上由微生物呼吸酶活性(xing)(xing)所確定,不(bu)同的(de)(de)(de)反應(ying)系統和(he)基質對(dui)陽(yang)極(ji)(ji)(ji)(ji)電(dian)(dian)(dian)(dian)勢(shi)(shi)影響(xiang)不(bu)大(da)(da),通常為(wei)(wei)-300 mV(相對(dui)于標準氫電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)(ji))。因此為(wei)(wei)了獲得最大(da)(da)的(de)(de)(de)輸出(chu)功(gong)率必須(xu)提高陰(yin)極(ji)(ji)(ji)(ji)電(dian)(dian)(dian)(dian)勢(shi)(shi)。陰(yin)極(ji)(ji)(ji)(ji)電(dian)(dian)(dian)(dian)勢(shi)(shi)隨著陰(yin)極(ji)(ji)(ji)(ji)電(dian)(dian)(dian)(dian)解(jie)液和(he)電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)(ji)材(cai)料(liao)的(de)(de)(de)選(xuan)擇變(bian)化很大(da)(da)。在(zai)(zai)陰(yin)極(ji)(ji)(ji)(ji)以(yi)含(han)飽和(he)氧(yang)的(de)(de)(de)水(shui)作(zuo)(zuo)為(wei)(wei)電(dian)(dian)(dian)(dian)解(jie)液導致明(ming)顯的(de)(de)(de)陰(yin)極(ji)(ji)(ji)(ji)低電(dian)(dian)(dian)(dian)勢(shi)(shi)。因為(wei)(wei)氧(yang)在(zai)(zai)水(shui)中(zhong)的(de)(de)(de)溶解(jie)性(xing)(xing)較差,而且基質傳遞受限,致使(shi)其(qi)在(zai)(zai)固(gu)體電(dian)(dian)(dian)(dian)極(ji)(ji)(ji)(ji)表面的(de)(de)(de)還原較慢。可以(yi)通過向陰(yin)極(ji)(ji)(ji)(ji)投加鐵(tie)(tie)氰化物來替代溶解(jie)氧(yang)作(zuo)(zuo)為(wei)(wei)更好的(de)(de)(de)電(dian)(dian)(dian)(dian)子受體。實(shi)驗表明(ming),在(zai)(zai)H型(xing)(xing)微生物燃料(liao)電(dian)(dian)(dian)(dian)池(chi)中(zhong),使(shi)用鐵(tie)(tie)氰化物型(xing)(xing)陰(yin)極(ji)(ji)(ji)(ji)比使(shi)用鉑-空氣型(xing)(xing)陰(yin)極(ji)(ji)(ji)(ji)產生的(de)(de)(de)電(dian)(dian)(dian)(dian)流輸出(chu)功(gong)率要大(da)(da)1.5~1.8倍(bei)[4]。
3.3.3質子交(jiao)換膜的優化(hua)
質(zhi)(zhi)子(zi)交(jiao)換(huan)(huan)膜(mo)(mo)(PEM)對于(yu)(yu)維持MFC電(dian)極(ji)(ji)(ji)兩端pH的(de)平(ping)衡、電(dian)極(ji)(ji)(ji)反應的(de)正常進(jin)行(xing)都起到重(zhong)要的(de)作用。理想(xiang)的(de)質(zhi)(zhi)子(zi)交(jiao)換(huan)(huan)膜(mo)(mo)應具(ju)有(you):(1)將(jiang)質(zhi)(zhi)子(zi)高效率傳(chuan)遞(di)到陰(yin)極(ji)(ji)(ji);(2)阻止燃料(底物)或電(dian)子(zi)受體(氧(yang)氣(qi))的(de)遷移。但(dan)通(tong)常的(de)情況(kuang)是(shi),質(zhi)(zhi)子(zi)交(jiao)換(huan)(huan)膜(mo)(mo)微(wei)弱的(de)質(zhi)(zhi)子(zi)傳(chuan)遞(di)能(neng)力改變了(le)陰(yin)陽(yang)極(ji)(ji)(ji)的(de)pH,從而(er)減弱了(le)微(wei)生物活性和電(dian)子(zi)傳(chuan)遞(di)能(neng)力,并且陰(yin)極(ji)(ji)(ji)質(zhi)(zhi)子(zi)供給的(de)限制(zhi)影響了(le)氧(yang)氣(qi)的(de)還原反應。目前,研究(jiu)最多(duo)的(de)是(shi)一種(zhong)全氟磺(huang)酸質(zhi)(zhi)子(zi)交(jiao)換(huan)(huan)膜(mo)(mo),具(ju)有(you)較高的(de)離子(zi)傳(chuan)導性,但(dan)因其成本(ben)及氧(yang)氣(qi)擴(kuo)散的(de)限制(zhi)而(er)不利于(yu)(yu)工業化。不使(shi)用質(zhi)(zhi)子(zi)交(jiao)換(huan)(huan)膜(mo)(mo)將(jiang)是(shi)經濟有(you)效的(de)MFC設計方(fang)式,Ghangrekar等(deng)[5]構建了(le)一種(zhong)無(wu)膜(mo)(mo)微(wei)生物燃料電(dian)池,在用于(yu)(yu)處理人工合成廢水時COD、BOD和總(zong)凱(kai)氏氮去除率分別達到88 %、87 %和50 %,同時通(tong)過縮短電(dian)極(ji)(ji)(ji)距離獲(huo)得了(le)10.09mW·m-2的(de)電(dian)流輸出功率。
4 MFC應用潛力(li)
從(cong)微(wei)生物(wu)(wu)角度考慮,微(wei)生物(wu)(wu)燃料(liao)電(dian)(dian)池(chi)廢水(shui)處理(li)技(ji)術(shu)是(shi)一種(zhong)厭氧生物(wu)(wu)處理(li)工(gong)藝(yi),但又不同于傳統的(de)(de)厭氧工(gong)藝(yi)。微(wei)生物(wu)(wu)燃料(liao)電(dian)(dian)池(chi)與現行的(de)(de)有機(ji)物(wu)(wu)發電(dian)(dian)和污水(shui)處理(li)技(ji)術(shu)相比,不論從(cong)運行還是(shi)功能(neng)方面都具有很多優點。
(1)可利(li)用生(sheng)物廢物/有機物發(fa)電,清潔環(huan)保
它能夠直接利用生物(wu)廢物(wu)和有機(ji)物(wu)產生電能,產出(chu)的能量可以用作污水處理廠的運行(xing),或者在(zai)電力市(shi)場出(chu)售(shou)。
(2)將(jiang)底物(wu)直接轉(zhuan)(zhuan)化(hua)為電能,能量轉(zhuan)(zhuan)化(hua)率高
在厭(yan)氧處理過程(cheng)中(zhong),產生的(de)沼氣(qi)燃(ran)燒發電時,以電能(neng)輸出的(de)能(neng)量(liang)(liang)(liang)至多只能(neng)占輸入(ru)能(neng)量(liang)(liang)(liang)的(de)1/3。雖然通過熱能(neng)形式可以回收一部分能(neng)量(liang)(liang)(liang),但(dan)總(zong)的(de)效(xiao)(xiao)(xiao)率(lv)仍然停留(liu)在30 %。而由(you)于微(wei)生物燃(ran)料電池的(de)能(neng)量(liang)(liang)(liang)轉(zhuan)化沒有(you)中(zhong)間過程(cheng),因此能(neng)量(liang)(liang)(liang)轉(zhuan)化效(xiao)(xiao)(xiao)率(lv)相應升高,實際總(zong)效(xiao)(xiao)(xiao)率(lv)可達到80 %。
(3)復電快
MFC并不像(xiang)常規的(de)(de)電池那樣,在使用(yong)了(le)一定(ding)時間(jian)以后需要充(chong)電才能繼續使用(yong)。每次利用(yong)很(hen)短的(de)(de)時間(jian)補充(chong)底物MFC就可以繼續工作。
(4)污泥產量低
目(mu)前,處(chu)(chu)理(li)(li)中低(di)濃度(du)有機(ji)廢(fei)(fei)水多(duo)使用傳(chuan)統的(de)是好(hao)氧(yang)處(chu)(chu)理(li)(li),其最大缺點主要為(wei)能(neng)耗高(gao)(1 kWh·kg-1 碳水化合物(wu))和剩(sheng)余污(wu)(wu)(wu)泥(ni)(ni)產量(liang)大(0.4 g 污(wu)(wu)(wu)泥(ni)(ni)·g-1 基(ji)質(zhi)(zhi))。針對高(gao)強度(du)的(de)有機(ji)廢(fei)(fei)水的(de)處(chu)(chu)理(li)(li)通常使用USB 法,負荷速率(lv)(lv)(lv)通常為(wei):10~20 kgCOD·m-3·d-1,并且具有(帶有一個燃(ran)燒引擎作為(wei)轉換器)35 %的(de)總(zong)電(dian)力效率(lv)(lv)(lv),意味著(zhu)反(fan)應(ying)器功率(lv)(lv)(lv)輸出為(wei)0.5~1 kW·m-3。它的(de)效率(lv)(lv)(lv)主要決定于(yu)燃(ran)燒沼氣時損(sun)失的(de)能(neng)量(liang)。厭(yan)氧(yang)消(xiao)化相對于(yu)耗氧(yang)處(chu)(chu)理(li)(li)剩(sheng)余污(wu)(wu)(wu)泥(ni)(ni)產量(liang)大大減少,理(li)(li)論上僅為(wei)0.077 污(wu)(wu)(wu)泥(ni)(ni)g-1 基(ji)質(zhi)(zhi)。基(ji)于(yu)微(wei)生物(wu)燃(ran)料電(dian)池過程的(de)本質(zhi)(zhi),其剩(sheng)余污(wu)(wu)(wu)泥(ni)(ni)產量(liang)應(ying)該介于(yu)耗氧(yang)處(chu)(chu)理(li)(li)與厭(yan)氧(yang)消(xiao)化兩種代謝類型之(zhi)間。以葡萄糖飼喂(wei)的(de)微(wei)生物(wu)燃(ran)料電(dian)池的(de)生長速率(lv)(lv)(lv)在0.07~0.22 之(zhi)間。由于(yu)廢(fei)(fei)水處(chu)(chu)理(li)(li)設備中剩(sheng)余污(wu)(wu)(wu)泥(ni)(ni)處(chu)(chu)理(li)(li)的(de)花費數(shu)額巨大,這(zhe)一數(shu)量(liang)的(de)減少對于(yu)該過程的(de)經濟平衡(heng)具有重要的(de)提示意義。
(5)簡化了(le)氣(qi)體(ti)處理過程(cheng)
一般厭氧處理(li)過程排(pai)出(chu)(chu)的(de)氣體(ti)含(han)有(you)高(gao)濃度(du)的(de)氮氣、硫化(hua)氫和(he)二氧化(hua)碳,其(qi)次是需要的(de)甲(jia)烷或氫氣。MFC排(pai)出(chu)(chu)的(de)氣體(ti)一般無(wu)毒無(wu)害,可以直接排(pai)放;
(6)可節省(sheng)曝氣裝置,如(ru)果(guo)采用(yong)單室MFC,選(xuan)用(yong)空(kong)氣陰極,被動通風的方式,則不需外(wai)加能量用(yong)于曝氣。
毋(wu)庸置(zhi)疑(yi),MFC 技術(shu)作為同步廢水處(chu)理與(yu)(yu)產電(dian)的新興(xing)概(gai)念廢水處(chu)理技術(shu),代表了(le)未來水處(chu)理技術(shu)與(yu)(yu)廢水資源化發展(zhan)的方向。目前(qian),MFC 的研究仍處(chu)于(yu)研究積累(lei)階段,所(suo)獲得的認識(shi)和信(xin)息還相當有限,要推(tui)動其在實際(ji)廢水處(chu)理中的應(ying)用尚需做大量的研究與(yu)(yu)技術(shu)突破。
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(本文(wen)文(wen)獻格式:師波,徐振波.微生(sheng)物燃料電池廢水生(sheng)物處理技(ji)術[J].廣東化工,2011,38(10):95-96)

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