MBR工藝介紹
在(zai)污水處理,水資(zi)源再利用領域,MBR又稱膜生物反應器,是一種由(you)活性污泥法與膜分離技術(shu)相結合的新(xin)型水處理技術(shu)。
在污水(shui)處理,水(shui)資源再利用領(ling)域,MBR又稱膜(mo)(mo)生(sheng)物反(fan)應器(Membrane Bio-Reactor),是一種由(you)活性(xing)污泥法與MBR膜(mo)(mo)圖片膜(mo)(mo)分(fen)(fen)離技(ji)術相結(jie)(jie)合的新(xin)型(xing)(xing)水(shui)處理技(ji)術。膜(mo)(mo)的種類繁多,按分(fen)(fen)離機理進行分(fen)(fen)類,有(you)反(fan)應膜(mo)(mo)、離子交換膜(mo)(mo)、滲透膜(mo)(mo)等(deng);按膜(mo)(mo)的性(xing)質(zhi)分(fen)(fen)類,有(you)天(tian)然膜(mo)(mo)(生(sheng)物膜(mo)(mo))和合成膜(mo)(mo)(有(you)機膜(mo)(mo)和無機膜(mo)(mo));按膜(mo)(mo)的結(jie)(jie)構型(xing)(xing)式分(fen)(fen)類,有(you)平板型(xing)(xing)、管型(xing)(xing)、螺旋型(xing)(xing)及中(zhong)空纖維型(xing)(xing)等(deng)。
MBR工藝組成
膜- 生(sheng)物(wu)(wu)反(fan)應(ying)(ying)(ying)器主(zhu)要由(you)膜分離(li)(li)組(zu)件及生(sheng)物(wu)(wu)反(fan)應(ying)(ying)(ying)器兩部(bu)分組(zu)成。通常提到的膜 - 生(sheng)物(wu)(wu)反(fan)應(ying)(ying)(ying)器實(shi)際上是(shi)三類反(fan)應(ying)(ying)(ying)器的總稱: ① 曝(pu)氣膜 - 生(sheng)物(wu)(wu)反(fan)應(ying)(ying)(ying)器(Aeration Membrane Bioreactor, AMBR) ; ② 萃取膜 - 生(sheng)物(wu)(wu)反(fan)應(ying)(ying)(ying)器( ExtractiveMembrane Bioreactor, EMBR ); ③ 固液分離(li)(li)型膜 - 生(sheng)物(wu)(wu)反(fan)應(ying)(ying)(ying)器( Solid/Liquid SeparationMembrane Bioreactor, SLSMBR, 簡(jian)稱 MBR )。
曝氣膜(mo)(mo)曝氣膜(mo)(mo) -生(sheng)物反應(ying)器(qi)最(zui)早見于 Cote.P 等 1988年報道,采用透(tou)氣性致密膜(mo)(mo)(如硅橡膠膜(mo)(mo))或微孔(kong)膜(mo)(mo)(如疏水性聚合膜(mo)(mo)),以板式(shi)或中空纖維式(shi)組件,在(zai)保(bao)持氣體分(fen)壓低于泡(pao)點(dian)(dian)( Bubble Point)情(qing)況下,可實現(xian)向生(sheng)物反應(ying)器(qi)的無泡(pao)曝氣。該工藝的特點(dian)(dian)是提高了(le)接觸時間和(he)傳氧(yang)效率,有利(li)于曝氣工藝的控制,不受(shou)傳統曝氣中氣泡(pao)大小(xiao)和(he)停留時間的因素的影響。如圖 [1] 所示。
萃(cui)取(qu)膜(mo)(mo)(mo)萃(cui)取(qu)膜(mo)(mo)(mo) - 生(sheng)(sheng)物(wu)(wu)(wu)(wu)反應器(qi) 又稱為 EMBR (Extractive Membrane Bioreactor)。因為高酸堿度或對(dui)生(sheng)(sheng)物(wu)(wu)(wu)(wu)有(you)毒(du)物(wu)(wu)(wu)(wu)質的存在(zai),某些工(gong)業廢(fei)水(shui)(shui)不(bu)宜采用(yong)與(yu)微(wei)生(sheng)(sheng)物(wu)(wu)(wu)(wu)直接(jie)接(jie)觸的方法處理(li);當廢(fei)水(shui)(shui)中含揮發(fa)性(xing)(xing)有(you)毒(du)物(wu)(wu)(wu)(wu)質時(shi),若采用(yong)傳統(tong)的好氧(yang)生(sheng)(sheng)物(wu)(wu)(wu)(wu)處理(li)過程,污(wu)染物(wu)(wu)(wu)(wu)容易隨曝氣氣流揮發(fa),發(fa)生(sheng)(sheng)氣提現象,不(bu)僅處理(li)效(xiao)果很不(bu)穩(wen)定(ding)(ding),還會造成(cheng)大(da)氣污(wu)染。為了解(jie)決這(zhe)些技術難題,英國學者 Livingston研(yan)究(jiu)開(kai)(kai)發(fa)了 EMB 。廢(fei)水(shui)(shui)與(yu)活性(xing)(xing)污(wu)泥被膜(mo)(mo)(mo)隔開(kai)(kai)來,廢(fei)水(shui)(shui)在(zai)膜(mo)(mo)(mo)內流動,而含某種專(zhuan)性(xing)(xing)細菌(jun)的活性(xing)(xing)污(wu)泥在(zai)膜(mo)(mo)(mo)外流動,廢(fei)水(shui)(shui)與(yu)微(wei)生(sheng)(sheng)物(wu)(wu)(wu)(wu)不(bu)直接(jie)接(jie)觸,有(you)機污(wu)染物(wu)(wu)(wu)(wu)可以選(xuan)擇性(xing)(xing)透過膜(mo)(mo)(mo)被另一側(ce)的微(wei)生(sheng)(sheng)物(wu)(wu)(wu)(wu)降解(jie)。由(you)于萃(cui)取(qu)膜(mo)(mo)(mo)兩側(ce)的生(sheng)(sheng)物(wu)(wu)(wu)(wu)反應器(qi)單元和廢(fei)水(shui)(shui)循環(huan)單元是各自(zi)獨立,各單元水(shui)(shui)流相互影(ying)響不(bu)大(da),生(sheng)(sheng)物(wu)(wu)(wu)(wu)反應器(qi)中營(ying)養物(wu)(wu)(wu)(wu)質和微(wei)生(sheng)(sheng)物(wu)(wu)(wu)(wu)生(sheng)(sheng)存條(tiao)(tiao)件不(bu)受廢(fei)水(shui)(shui)水(shui)(shui)質的影(ying)響,使水(shui)(shui)處理(li)效(xiao)果穩(wen)定(ding)(ding)。系統(tong)的運行條(tiao)(tiao)件如(ru) HRT 和 SRT 可分別控制在(zai)最優的范(fan)圍,維持最大(da)的污(wu)染物(wu)(wu)(wu)(wu)降解(jie)速率。
固(gu)(gu)液分(fen)(fen)離(li)(li)(li)型膜固(gu)(gu)液分(fen)(fen)離(li)(li)(li)型膜 - 生(sheng)物反應器是(shi)在(zai)(zai)水(shui)處(chu)理(li)(li)領(ling)域中(zhong)(zhong)(zhong)研究得最為(wei)廣(guang)泛深(shen)入的(de)(de)一類膜 -生(sheng)物反應器,是(shi)一種用膜分(fen)(fen)離(li)(li)(li)過(guo)(guo)程取代傳(chuan)(chuan)統(tong)(tong)(tong)活(huo)性(xing)(xing)(xing)(xing)污(wu)泥(ni)(ni)法中(zhong)(zhong)(zhong)二次沉(chen)淀池(chi)的(de)(de)水(shui)處(chu)理(li)(li)技(ji)術。在(zai)(zai)傳(chuan)(chuan)統(tong)(tong)(tong)的(de)(de)廢水(shui)生(sheng)物處(chu)理(li)(li)技(ji)術中(zhong)(zhong)(zhong),泥(ni)(ni)水(shui)分(fen)(fen)離(li)(li)(li)是(shi)在(zai)(zai)二沉(chen)池(chi)中(zhong)(zhong)(zhong)靠重力(li)作(zuo)用完成(cheng)的(de)(de),其分(fen)(fen)離(li)(li)(li)效率依賴于(yu)活(huo)性(xing)(xing)(xing)(xing)污(wu)泥(ni)(ni)的(de)(de)沉(chen)降(jiang)(jiang)(jiang)(jiang)(jiang)性(xing)(xing)(xing)(xing)能,沉(chen)降(jiang)(jiang)(jiang)(jiang)(jiang)性(xing)(xing)(xing)(xing)越好,泥(ni)(ni)水(shui)分(fen)(fen)離(li)(li)(li)效率越高(gao)。而(er)污(wu)泥(ni)(ni)的(de)(de)沉(chen)降(jiang)(jiang)(jiang)(jiang)(jiang)性(xing)(xing)(xing)(xing)取決于(yu)曝(pu)氣池(chi)的(de)(de)運行(xing)狀況(kuang),改(gai)善(shan)污(wu)泥(ni)(ni)沉(chen)降(jiang)(jiang)(jiang)(jiang)(jiang)性(xing)(xing)(xing)(xing)必須嚴格控制曝(pu)氣池(chi)的(de)(de)操(cao)作(zuo)條件,這限制了(le)(le)該方法的(de)(de)適用范圍。由(you)(you)于(yu)二沉(chen)池(chi)固(gu)(gu)液分(fen)(fen)離(li)(li)(li)的(de)(de)要求,曝(pu)氣池(chi)的(de)(de)污(wu)泥(ni)(ni)不能維持較高(gao)濃度,一般在(zai)(zai) 1.5~3.5mg/L左右,從而(er)限制了(le)(le)生(sheng)化(hua)反應速(su)率。水(shui)力(li)停(ting)留時(shi)間( HRT )與(yu)污(wu)泥(ni)(ni)齡( SRT)相互依賴,提高(gao)容積(ji)負(fu)荷與(yu)降(jiang)(jiang)(jiang)(jiang)(jiang)低污(wu)泥(ni)(ni)負(fu)荷往往形(xing)成(cheng)矛(mao)盾(dun)。系統(tong)(tong)(tong)在(zai)(zai)運行(xing)過(guo)(guo)程中(zhong)(zhong)(zhong)還產生(sheng)了(le)(le)大(da)量的(de)(de)剩余(yu)污(wu)泥(ni)(ni),其處(chu)置(zhi)費(fei)用占污(wu)水(shui)處(chu)理(li)(li)廠運行(xing)費(fei)用的(de)(de) 25% ~40% 。傳(chuan)(chuan)統(tong)(tong)(tong)活(huo)性(xing)(xing)(xing)(xing)污(wu)泥(ni)(ni)處(chu)理(li)(li)系統(tong)(tong)(tong)還容易出(chu)(chu)現(xian)污(wu)泥(ni)(ni)膨脹現(xian)象,出(chu)(chu)水(shui)中(zhong)(zhong)(zhong)含有懸(xuan)浮固(gu)(gu)體(ti),出(chu)(chu)水(shui)水(shui)質惡化(hua)。針(zhen)對上述問題, MBR將膜分(fen)(fen)離(li)(li)(li)技(ji)術與(yu)傳(chuan)(chuan)統(tong)(tong)(tong)生(sheng)物處(chu)理(li)(li)技(ji)術有機結(jie)合,MBR實現(xian)污(wu)泥(ni)(ni)停(ting)留時(shi)間和(he)水(shui)力(li)停(ting)留時(shi)間的(de)(de)分(fen)(fen)離(li)(li)(li),大(da)大(da)提高(gao)了(le)(le)固(gu)(gu)液分(fen)(fen)離(li)(li)(li)效率,并且(qie)由(you)(you)于(yu)曝(pu)氣池(chi)中(zhong)(zhong)(zhong)活(huo)性(xing)(xing)(xing)(xing)污(wu)泥(ni)(ni)濃度的(de)(de)增(zeng)大(da)和(he)污(wu)泥(ni)(ni)中(zhong)(zhong)(zhong)特(te)效菌 (特(te)別(bie)是(shi)優勢菌群 ) 的(de)(de)出(chu)(chu)現(xian),提高(gao)了(le)(le)生(sheng)化(hua)反應速(su)率。同(tong)時(shi),通過(guo)(guo)降(jiang)(jiang)(jiang)(jiang)(jiang)低 F/M比減(jian)少剩余(yu)污(wu)泥(ni)(ni)產生(sheng)量(甚至為(wei)零),從而(er)基本解決了(le)(le)傳(chuan)(chuan)統(tong)(tong)(tong)活(huo)性(xing)(xing)(xing)(xing)污(wu)泥(ni)(ni)法存(cun)在(zai)(zai)的(de)(de)許多突出(chu)(chu)問題。
MBR工藝(yi)類型
以下討(tao)論的均(jun)為固液分離型膜(mo) - 生物(wu)(wu)反應器(qi)。 根據膜(mo)組(zu)件和生物(wu)(wu)反應器(qi)的組(zu)合(he)(he)方式(shi)(shi),可(ke)將 膜(mo) - 生物(wu)(wu)反應器(qi) 分為分置式(shi)(shi)、一(yi)體式(shi)(shi)以及復(fu)合(he)(he)式(shi)(shi)三種基本(ben)類(lei)型 。
分(fen)置式膜(mo) - 生(sheng)(sheng)(sheng)(sheng)(sheng)物(wu)(wu)反(fan)應(ying)器把(ba)膜(mo)組件和生(sheng)(sheng)(sheng)(sheng)(sheng)物(wu)(wu)反(fan)應(ying)器分(fen)開設置,如圖 3所示。生(sheng)(sheng)(sheng)(sheng)(sheng)物(wu)(wu)反(fan)應(ying)器中的(de)(de)(de)混合液經循(xun)環(huan)泵(beng)增(zeng)壓后(hou)打至(zhi)膜(mo)組件的(de)(de)(de)過濾端,在(zai)壓力作用(yong)下混合液中的(de)(de)(de)液體透過膜(mo),成為系(xi)統處(chu)理(li)水;固形物(wu)(wu)、大分(fen)子(zi)物(wu)(wu)質等(deng)則被(bei)膜(mo)截留(liu),隨濃縮液回流(liu)到生(sheng)(sheng)(sheng)(sheng)(sheng)物(wu)(wu)反(fan)應(ying)器內(nei)。分(fen)置式膜(mo) -生(sheng)(sheng)(sheng)(sheng)(sheng)物(wu)(wu)反(fan)應(ying)器的(de)(de)(de)特點(dian)是運行穩定(ding)可靠,易于膜(mo)的(de)(de)(de)清(qing)洗(xi)、更(geng)換及增(zeng)設;而且膜(mo)通(tong)量普遍較(jiao)大。但一(yi)般(ban)條件下為減少(shao)污染物(wu)(wu)在(zai)膜(mo)表面(mian)的(de)(de)(de)沉積,延長膜(mo)的(de)(de)(de)清(qing)洗(xi)周期(qi),需要用(yong)循(xun)環(huan)泵(beng)提供較(jiao)高的(de)(de)(de)膜(mo)面(mian)錯流(liu)流(liu)速,水流(liu)循(xun)環(huan)量大、動力費用(yong)高 (Yamamoto, 1989),并且泵(beng)的(de)(de)(de)高速旋轉產生(sheng)(sheng)(sheng)(sheng)(sheng)的(de)(de)(de)剪切力會使(shi)某些微生(sheng)(sheng)(sheng)(sheng)(sheng)物(wu)(wu)菌體產生(sheng)(sheng)(sheng)(sheng)(sheng)失活現(xian)象 ( Brockmann and Seyfried, 1997 ) 。
一體式膜(mo) - 生(sheng)物(wu)(wu)反(fan)應(ying)器是(shi)把膜(mo)組(zu)件(jian)置于生(sheng)物(wu)(wu)反(fan)應(ying)器內部,如(ru)圖 4 所(suo)示。進水(shui)進入膜(mo) -生(sheng)物(wu)(wu)反(fan)應(ying)器,其(qi)中(zhong)的大部分污染(ran)物(wu)(wu)被混(hun)合(he)液中(zhong)的活性污泥去除,再(zai)在外壓作用(yong)下由膜(mo)過濾出水(shui)。這種形(xing)式的膜(mo) -生(sheng)物(wu)(wu)反(fan)應(ying)器由于省去了混(hun)合(he)液循環系(xi)統(tong),并且靠抽(chou)吸出水(shui),能耗相對(dui)較(jiao)低;占地(di)較(jiao)分置式更為緊湊,近(jin)年來在水(shui)處理領域受到(dao)了特(te)別(bie)關(guan)注。但是(shi)一般膜(mo)通量相對(dui)較(jiao)低,容易(yi)(yi)發生(sheng)膜(mo)污染(ran),膜(mo)污染(ran)后(hou)不(bu)容易(yi)(yi)清洗和更換。
復(fu)合式膜 - 生(sheng)物(wu)反(fan)應(ying)器(qi)(qi)在形(xing)式上也(ye)屬于一體式膜 - 生(sheng)物(wu)反(fan)應(ying)器(qi)(qi),所不同的是在生(sheng)物(wu)反(fan)應(ying)器(qi)(qi)內加裝填料,從而形(xing)成復(fu)合式膜 - 生(sheng)物(wu)反(fan)應(ying)器(qi)(qi),改變了(le)反(fan)應(ying)器(qi)(qi)的某些性(xing)狀(zhuang)
MBR工藝(yi)特點
與(yu)許多傳統(tong)的生物水處理工藝相(xiang)比, MBR 具有(you)以下(xia)主要特(te)點:
一、出水(shui)(shui)(shui)(shui)(shui)(shui)水(shui)(shui)(shui)(shui)(shui)(shui)質(zhi)優(you)質(zhi)穩(wen)定由于(yu)膜的(de)(de)高(gao)(gao)效分(fen)(fen)離(li)作(zuo)用,分(fen)(fen)離(li)效果遠好于(yu)傳統沉淀池,處理出水(shui)(shui)(shui)(shui)(shui)(shui)極其清澈, 懸浮物和濁度(du)接(jie)近(jin)于(yu)零,細菌(jun)和病毒被(bei)大幅去(qu)除 ,出水(shui)(shui)(shui)(shui)(shui)(shui)水(shui)(shui)(shui)(shui)(shui)(shui)質(zhi)優(you)于(yu)建(jian)設(she)部頒發的(de)(de)生活雜用水(shui)(shui)(shui)(shui)(shui)(shui)水(shui)(shui)(shui)(shui)(shui)(shui)質(zhi)標準(zhun)( CJ25.1-89 ),可以(yi)直(zhi)接(jie)作(zuo)為(wei)非飲用市政雜用水(shui)(shui)(shui)(shui)(shui)(shui)進行(xing)回用。同時,膜分(fen)(fen)離(li)也使(shi) 微(wei)生物被(bei)完全被(bei)截(jie)流在生物反應(ying)器(qi)內, 使(shi)得系統內能夠維持較高(gao)(gao)的(de)(de)微(wei)生物濃度(du),不但提高(gao)(gao)了(le)反應(ying)裝(zhuang)置對污染(ran)物的(de)(de)整體去(qu)除效率,保(bao)證(zheng)了(le)良好的(de)(de)出水(shui)(shui)(shui)(shui)(shui)(shui)水(shui)(shui)(shui)(shui)(shui)(shui)質(zhi),同時反應(ying)器(qi)對進水(shui)(shui)(shui)(shui)(shui)(shui)負(fu)荷(水(shui)(shui)(shui)(shui)(shui)(shui)質(zhi)及水(shui)(shui)(shui)(shui)(shui)(shui)量)的(de)(de)各種變化(hua)具有很(hen)好的(de)(de)適應(ying)性,耐沖擊負(fu)荷,能夠穩(wen)定獲得優(you)質(zhi)的(de)(de)出水(shui)(shui)(shui)(shui)(shui)(shui)水(shui)(shui)(shui)(shui)(shui)(shui)質(zhi)。
二、剩(sheng)(sheng)余(yu)污(wu)泥產量(liang)(liang)少該工藝可以在高(gao)容(rong)積負荷、低(di)污(wu)泥負荷下運行(xing),剩(sheng)(sheng)余(yu)污(wu)泥產量(liang)(liang)低(di)(理(li)論上可以實現(xian)零污(wu)泥排放),降低(di)了污(wu)泥處理(li)費用。
三、占地(di)(di)面積(ji)小(xiao),不(bu)受設置(zhi)場合(he)限(xian)制生(sheng)物反應器(qi)內能維持高濃(nong)度的(de)微(wei)生(sheng)物量,處理(li)裝置(zhi)容積(ji)負荷(he)高,占地(di)(di)面積(ji)大(da)大(da)節(jie)省; 該工藝流程(cheng)簡單、結構緊(jin)湊、占地(di)(di)面積(ji)省,不(bu)受設置(zhi)場所限(xian)制,適(shi)合(he)于任何場合(he),可(ke)做成地(di)(di)面式、半地(di)(di)下式和地(di)(di)下式。
四、可去(qu)除氨氮及難(nan)(nan)降解(jie)有機物(wu)由于微(wei)生物(wu)被完全截流在生物(wu)反應(ying)器(qi)內,從(cong)而有利(li)于增(zeng)殖緩慢(man)的(de)微(wei)生物(wu)如硝(xiao)化(hua)細菌的(de)截留生長,系統硝(xiao)化(hua)效率得以提高。同時(shi),可增(zeng)長一些難(nan)(nan)降解(jie)的(de)有機物(wu)在系統中的(de)水力停留時(shi)間,有利(li)于難(nan)(nan)降解(jie)有機物(wu)降解(jie)效率的(de)提高。
五、操(cao)作管(guan)理(li)方便,易于(yu)實現(xian)自動控制(zhi)該工(gong)藝實現(xian)了水力(li)停留時(shi)間( HRT )與污泥停留時(shi)間( SRT )的(de)完全分離,運行控制(zhi)更加靈(ling)活穩(wen)定,是污水處理(li)中容易實現(xian)裝備化的(de)新(xin)技術,可實現(xian)微機(ji)自動控制(zhi),從而使操(cao)作管(guan)理(li)更為方便。
六、易于從傳統工(gong)藝進行改造該工(gong)藝可以作為傳統污水(shui)處(chu)理工(gong)藝的(de)深(shen)(shen)度(du)(du)處(chu)理單元,在城市二(er)級污水(shui)處(chu)理廠出水(shui)深(shen)(shen)度(du)(du)處(chu)理(從而實現城市污水(shui)的(de)大量(liang)回用)等領(ling)域有(you)著(zhu)廣闊的(de)應用前景(jing)。
膜 - 生物反應器也存(cun)在一(yi)些不足(zu)。主(zhu)要表(biao)現在以(yi)下幾個方面:
o 膜造價高,使膜 - 生物(wu)反應器的(de)基建投資(zi)高于傳統(tong)污水處理工藝;
o 膜污染容(rong)易(yi)出現,給操作管理帶(dai)來不(bu)便;
o 能耗高:首先 MBR 泥水分離過程必須保(bao)持一定(ding)的(de)膜(mo)驅動壓力,其次(ci)是 MBR 池中 MLSS 濃度非常高,要(yao)保(bao)持足夠的(de)傳(chuan)氧(yang)速率,必須加大曝(pu)氣強度,還有為了加大膜(mo)通量、減輕膜(mo)污染(ran),必須增大流速,沖(chong)刷(shua)膜(mo)表面(mian),造成 MBR 的(de)能耗要(yao)比(bi)傳(chuan)統的(de)生物處(chu)理工藝高。
中天恒遠(yuan)污水處(chu)理設備聯系方式:
銷售熱線:010-8022-5898
手機號碼:177-1052-7434