活性炭對微濾膜的影響

　　活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)吸(xi)附對微(wei)濾(lv)膜(mo)性(xing)(xing)能(neng)的影(ying)(ying)響。結(jie)果(guo)表(biao)明(ming)，活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)預處(chu)理為10-200 mg / L 在(zai)劑量(liang)下，溶解(jie)有(you)機(ji)(ji)(ji)(ji)碳(tan)(DOC)和254 nm紫外吸(xi)收光(guang)譜(UV 254)都能(neng)提供高(gao)有(you)機(ji)(ji)(ji)(ji)物(wu)(wu)(wu)去除率。通過(guo)MF隨著活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)吸(xi)附有(you)機(ji)(ji)(ji)(ji)物(wu)(wu)(wu)的增加(jia)，膜(mo)過(guo)濾(lv)去除效率降(jiang)低。主要去除活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)約3kDa有(you)機(ji)(ji)(ji)(ji)物(wu)(wu)(wu)質(zhi)(zhi)的分子量(liang)。活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)吸(xi)附后，膜(mo)在(zai)膜(mo)上保(bao)持超過(guo)5kDa有(you)機(ji)(ji)(ji)(ji)物(wu)(wu)(wu)質(zhi)(zhi)。膜(mo)過(guo)濾(lv)結(jie)果(guo)表(biao)明(ming)，無(wu)論活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)劑量(liang)如何，活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)的預處(chu)理都略(lve)微(wei)促進膜(mo)通量(liang)。似乎有(you)機(ji)(ji)(ji)(ji)污垢膜(mo)集中(zhong)在(zai)3以上kDa的微(wei)濾(lv)膜(mo)。活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)去除明(ming)顯小(xiao)于33kDa 微(wei)濾(lv)膜(mo)有(you)機(ji)(ji)(ji)(ji)物(wu)(wu)(wu)超過(guo)3種kDa有(you)機(ji)(ji)(ji)(ji)物(wu)(wu)(wu)質(zhi)(zhi)的影(ying)(ying)響較小(xiao)。因此，活(huo)(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)不能(neng)減少膜(mo)污染。

　　膜污染是(shi)水(shui)處理的(de)重要問題之一。膜結(jie)垢導致膜通(tong)量降低和(he)性(xing)能(neng)差。一些(xie)研究表(biao)明，天然有(you)機物(NOM)負責炭(tan)吸附是(shi)飲用水(shui)中負責微(wei)濾膜污染或垢。活性(xing)炭(tan)吸附是(shi)減少有(you)機物污染膜的(de)好選(xuan)擇。

　　活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)廣泛用作水(shui)處理中(zhong)的(de)(de)吸收劑。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)具有(you)良(liang)好的(de)(de)天然(ran)有(you)機(ji)物(wu)吸附(fu)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)，因(yin)此采用預(yu)處理，減少膜(mo)污(wu)染，提高膜(mo)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。然(ran)而(er)，活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)對(dui)提高膜(mo)性(xing)(xing)(xing)(xing)(xing)(xing)能(neng)的(de)(de)效率(lv)有(you)不同(tong)的(de)(de)結論。一(yi)些(xie)研(yan)(yan)究(jiu)表(biao)明(ming)，當活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)保持膜(mo)表(biao)面時(shi)，活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)可(ke)(ke)以增(zeng)強膜(mo)通(tong)量 。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)懸(xuan)浮在活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)/超(chao)濾(lv)系(xi)統中(zhong)的(de)(de)作用是吸收低分(fen)子腐殖酸(HA)。膜(mo)提供(gong)物(wu)理屏障，防止活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)通(tong)過(guo)(guo)(guo)，從而(er)保留吸附(fu)在活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)上的(de)(de)有(you)機(ji)化合物(wu)。發(fa)(fa)現(xian)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)可(ke)(ke)能(neng)導(dao)致(zhi)更大(da)的(de)(de)絮凝顆(ke)粒，并通(tong)過(guo)(guo)(guo)預(yu)處理活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)來減少每個(ge)過(guo)(guo)(guo)濾(lv)周期的(de)(de)可(ke)(ke)逆性(xing)(xing)(xing)(xing)(xing)(xing)TMP增(zeng)加(jia)。研(yan)(yan)究(jiu)天然(ran)有(you)機(ji)物(wu)在耦(ou)合超(chao)細活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)/微(wei)濾(lv)膜(mo)過(guo)(guo)(guo)程(cheng)中(zhong)的(de)(de)作用表(biao)明(ming)，天然(ran)有(you)機(ji)物(wu)被證明(ming)是膜(mo)污(wu)染和超(chao)細活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)主(zhu)要(yao)原(yuan)因(yin)，活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)實際上比單獨的(de)(de)天然(ran)有(you)機(ji)物(wu)減少了(le)結垢。然(ran)而(er)，一(yi)些(xie)研(yan)(yan)究(jiu)人員報告說，活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)存在會加(jia)重膜(mo)污(wu)染或不影響膜(mo)通(tong)量。 在反洗水(shui)中(zhong)發(fa)(fa)現(xian)活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)顆(ke)粒，因(yin)為(wei)它們(men)可(ke)(ke)能(neng)在污(wu)垢層的(de)(de)生長(chang)過(guo)(guo)(guo)程(cheng)中(zhong)積(ji)累。活(huo)(huo)(huo)(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)既不促進也不控(kong)制膜(mo)可(ke)(ke)逆結垢。

　　活性(xing)(xing)炭用(yong)于處(chu)理(li)微(wei)濾(lv)(lv)(lv)膜(mo)(mo)(mo)前(qian)的預處(chu)理(li)和地表水(shui)(shui)。實驗的主(zhu)要(yao)目的是(shi)研(yan)究活性(xing)(xing)炭對膜(mo)(mo)(mo)性(xing)(xing)能的影響(xiang)(xiang)，特別關注(zhu)活性(xing)(xing)炭微(wei)濾(lv)(lv)(lv)膜(mo)(mo)(mo)工藝對有機物去除率和膜(mo)(mo)(mo)通量的影響(xiang)(xiang)。木質活性(xing)(xing)炭。粒度分(fen)(fen)布(bu)為：>74μm-71%，>44μm-95%。使用(yong)前(qian)，加(jia)入少量去離子水(shui)(shui)均勻化(hua)活性(xing)(xing)炭。在原水(shui)(shui)中(zhong)加(jia)入10、50、100、200mg / L特殊活性(xing)(xing)炭劑量。本(ben)實驗采用(yong)黃浦江地表水(shui)(shui)。在水(shui)(shui)樣中(zhong)加(jia)入活性(xing)(xing)炭100rpm快速攪(jiao)(jiao)拌30分(fen)(fen)鐘(zhong)1分(fen)(fen)鐘(zhong)，攪(jiao)(jiao)拌30分(fen)(fen)鐘(zhong)rpm緩慢混合(he)，然后用(yong)0.45μm過(guo)(guo)(guo)濾(lv)(lv)(lv)器過(guo)(guo)(guo)濾(lv)(lv)(lv)水(shui)(shui)樣品。以下(xia)膜(mo)(mo)(mo)過(guo)(guo)(guo)濾(lv)(lv)(lv)用(yong)過(guo)(guo)(guo)濾(lv)(lv)(lv)水(shui)(shui)樣品。

　　溶解有機碳和(he)活性炭和(he)微濾過程UV254去除(chu)率(lv)

　　活(huo)性(xing)炭(tan)(tan)和UV如(ru)圖所示，254的(de)效(xiao)率。活(huo)性(xing)炭(tan)(tan)溶(rong)解有(you)機(ji)碳(tan)去(qu)除(chu)(chu)率較(jiao)高。活(huo)性(xing)炭(tan)(tan)劑(ji)(ji)量(liang)為10-2000 mg / L當(dang)溶(rong)解有(you)機(ji)碳(tan)的(de)去(qu)除(chu)(chu)率從(cong)3開始(shi).0%提高到59.8%。活(huo)性(xing)炭(tan)(tan)吸(xi)附(fu)后(hou)，微濾(lv)(lv)(lv)膜過濾(lv)(lv)(lv)水(shui)樣(yang)，溶(rong)解有(you)機(ji)碳(tan)從(cong)21中(zhong)去(qu)除(chu)(chu)滲透物.1%穩定增加(jia)到62.2%。然而，隨(sui)著活(huo)性(xing)炭(tan)(tan)劑(ji)(ji)量(liang)的(de)增加(jia)，微濾(lv)(lv)(lv)膜溶(rong)解有(you)機(ji)碳(tan)去(qu)除(chu)(chu)量(liang)略(lve)有(you)增加(jia)。

　　與溶(rong)解(jie)有(you)機碳(tan)相比(bi)，UV254去(qu)除率高。隨著活(huo)性(xing)炭(tan)劑量(liang)(liang)(liang)從100開始(shi)mg / L增加到200mg / L，超濾(lv)吸收去(qu)除率為10.1%增加到70.3%。與微(wei)濾(lv)過濾(lv)后(hou)溶(rong)解(jie)有(you)機碳(tan)去(qu)除率相似，活(huo)性(xing)炭(tan)用量(liang)(liang)(liang)越(yue)高，微(wei)濾(lv)膜去(qu)除UV254越(yue)低。可溶(rong)解(jie)有(you)機碳(tan)和(he)活(huo)性(xing)炭(tan)UV254去(qu)除率高，活(huo)性(xing)炭(tan)含(han)量(liang)(liang)(liang)高，膜可去(qu)除殘留有(you)機物。

　　在上述研究中(zhong)(zhong)，活(huo)性(xing)炭(tan)具(ju)有(you)較(jiao)高的(de)有(you)機(ji)物去除率(lv)。然而，即使在200年mg / L活(huo)性(xing)炭(tan)高的(de)劑量下，活(huo)性(xing)炭(tan)不能改善膜通(tong)量。原水有(you)機(ji)質(zhi)的(de)微濾濃度(du)為(wei)2-7kDa，特別是3-5kDa。活(huo)性(xing)炭(tan)吸附的(de)有(you)機(ji)物濃度(du)約為(wei)3kDa 水中(zhong)(zhong)有(you)機(ji)物分子量。顯然，活(huo)性(xing)炭(tan)對水中(zhong)(zhong)有(you)機(ji)物分子物質(zhi)影響(xiang)不大。

　　微濾(lv)膜(mo)(mo)(mo)過(guo)(guo)濾(lv)后(hou)原(yuan)水(shui)(shui)(shui)(shui)的(de)疏(shu)水(shui)(shui)(shui)(shui)性(xing)(xing)(xing)(xing)(xing)/親(qin)水(shui)(shui)(shui)(shui)性(xing)(xing)(xing)(xing)(xing)變化(hua)如圖(tu)6所示。可(ke)見，微濾(lv)膜(mo)(mo)(mo)主要(yao)去(qu)(qu)除疏(shu)水(shui)(shui)(shui)(shui)有機物(wu)。圖(tu)7顯示了原(yuan)水(shui)(shui)(shui)(shui)中(zhong)不同水(shui)(shui)(shui)(shui)中(zhong)有機物(wu)分(fen)子量的(de)疏(shu)水(shui)(shui)(shui)(shui)性(xing)(xing)(xing)(xing)(xing)/親(qin)水(shui)(shui)(shui)(shui)性(xing)(xing)(xing)(xing)(xing)變化(hua)。膜(mo)(mo)(mo)過(guo)(guo)濾(lv)后(hou)，疏(shu)水(shui)(shui)(shui)(shui)有機質的(de)比(bi)例(li)(li)明顯下降，特別是(shi)(shi)2-7 kDa 有機物(wu)。相(xiang)比(bi)之(zhi)下，親(qin)水(shui)(shui)(shui)(shui)性(xing)(xing)(xing)(xing)(xing)有機物(wu)的(de)比(bi)例(li)(li)顯著增(zeng)加。本(ben)研究采用親(qin)水(shui)(shui)(shui)(shui)性(xing)(xing)(xing)(xing)(xing)PVDF膜(mo)(mo)(mo)。因此，疏(shu)水(shui)(shui)(shui)(shui)物(wu)質不能通(tong)(tong)過(guo)(guo)膜(mo)(mo)(mo)并停留在膜(mo)(mo)(mo)表面。親(qin)水(shui)(shui)(shui)(shui)性(xing)(xing)(xing)(xing)(xing)有機物(wu)容易通(tong)(tong)過(guo)(guo)膜(mo)(mo)(mo)，然后(hou)親(qin)水(shui)(shui)(shui)(shui)性(xing)(xing)(xing)(xing)(xing)有機物(wu)在滲透物(wu)中(zhong)的(de)比(bi)例(li)(li)顯著增(zeng)加。膜(mo)(mo)(mo)有機污(wu)染物(wu)似(si)乎是(shi)(shi)2-7kDa 疏(shu)水(shui)(shui)(shui)(shui)有機物(wu)是(shi)(shi)重點。活性(xing)(xing)(xing)(xing)(xing)炭僅部分(fen)吸附2-7 kDa 有機物(wu)，輕微促進膜(mo)(mo)(mo)污(wu)染。這(zhe)是(shi)(shi)因為活性(xing)(xing)(xing)(xing)(xing)炭顯著去(qu)(qu)除有機物(wu)，增(zeng)強膜(mo)(mo)(mo)通(tong)(tong)量。