活性炭對微濾膜的影響

　　活(huo)(huo)(huo)性(xing)炭(tan)吸(xi)附(fu)對微(wei)(wei)濾(lv)膜(mo)(mo)性(xing)能(neng)的影(ying)響。結果(guo)表(biao)明(ming)，活(huo)(huo)(huo)性(xing)炭(tan)預(yu)處(chu)理為(wei)10-200 mg / L 在劑(ji)量(liang)下，溶解有(you)機(ji)(ji)碳(tan)(DOC)和254 nm紫(zi)外吸(xi)收(shou)光譜(UV 254)都能(neng)提供高有(you)機(ji)(ji)物(wu)去(qu)除率。通(tong)過MF隨著(zhu)活(huo)(huo)(huo)性(xing)炭(tan)吸(xi)附(fu)有(you)機(ji)(ji)物(wu)的增加，膜(mo)(mo)過濾(lv)去(qu)除效(xiao)率降(jiang)低。主要去(qu)除活(huo)(huo)(huo)性(xing)炭(tan)約3kDa有(you)機(ji)(ji)物(wu)質(zhi)(zhi)(zhi)的分子量(liang)。活(huo)(huo)(huo)性(xing)炭(tan)吸(xi)附(fu)后，膜(mo)(mo)在膜(mo)(mo)上保持超過5kDa有(you)機(ji)(ji)物(wu)質(zhi)(zhi)(zhi)。膜(mo)(mo)過濾(lv)結果(guo)表(biao)明(ming)，無論(lun)活(huo)(huo)(huo)性(xing)炭(tan)劑(ji)量(liang)如何(he)，活(huo)(huo)(huo)性(xing)炭(tan)的預(yu)處(chu)理都略(lve)微(wei)(wei)促進膜(mo)(mo)通(tong)量(liang)。似乎有(you)機(ji)(ji)污垢膜(mo)(mo)集中在3以(yi)上kDa的微(wei)(wei)濾(lv)膜(mo)(mo)。活(huo)(huo)(huo)性(xing)炭(tan)去(qu)除明(ming)顯小于33kDa 微(wei)(wei)濾(lv)膜(mo)(mo)有(you)機(ji)(ji)物(wu)超過3種kDa有(you)機(ji)(ji)物(wu)質(zhi)(zhi)(zhi)的影(ying)響較小。因此，活(huo)(huo)(huo)性(xing)炭(tan)不能(neng)減少膜(mo)(mo)污染。

　　膜(mo)污(wu)(wu)染是(shi)(shi)水處理的(de)(de)重要問(wen)題之(zhi)一。膜(mo)結垢導致膜(mo)通(tong)量降低(di)和(he)性能差。一些研究表明，天然有(you)機(ji)物(NOM)負(fu)責(ze)炭吸附是(shi)(shi)飲用水中負(fu)責(ze)微濾膜(mo)污(wu)(wu)染或垢。活性炭吸附是(shi)(shi)減少有(you)機(ji)物污(wu)(wu)染膜(mo)的(de)(de)好選擇。

　　活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)廣泛用(yong)作水處理中(zhong)(zhong)的(de)(de)(de)吸(xi)(xi)收(shou)劑。活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)具(ju)有(you)(you)(you)良好的(de)(de)(de)天然(ran)有(you)(you)(you)機(ji)(ji)物(wu)吸(xi)(xi)附(fu)性(xing)(xing)(xing)(xing)能(neng)，因此采用(yong)預處理，減(jian)少膜(mo)污(wu)染，提(ti)高膜(mo)性(xing)(xing)(xing)(xing)能(neng)。然(ran)而(er)，活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)對提(ti)高膜(mo)性(xing)(xing)(xing)(xing)能(neng)的(de)(de)(de)效率(lv)有(you)(you)(you)不同的(de)(de)(de)結(jie)論。一(yi)些(xie)研究(jiu)表(biao)明(ming)，當活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)保(bao)(bao)持膜(mo)表(biao)面(mian)時，活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)可(ke)以增強(qiang)膜(mo)通量(liang) 。活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)懸浮在(zai)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)/超濾系統中(zhong)(zhong)的(de)(de)(de)作用(yong)是(shi)吸(xi)(xi)收(shou)低分子腐殖(zhi)酸(HA)。膜(mo)提(ti)供物(wu)理屏(ping)障，防止活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)通過(guo)(guo)(guo)，從而(er)保(bao)(bao)留(liu)吸(xi)(xi)附(fu)在(zai)活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)上的(de)(de)(de)有(you)(you)(you)機(ji)(ji)化合(he)物(wu)。發(fa)現活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)可(ke)能(neng)導致更大(da)的(de)(de)(de)絮(xu)凝顆(ke)粒，并通過(guo)(guo)(guo)預處理活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)來減(jian)少每個過(guo)(guo)(guo)濾周期的(de)(de)(de)可(ke)逆性(xing)(xing)(xing)(xing)TMP增加。研究(jiu)天然(ran)有(you)(you)(you)機(ji)(ji)物(wu)在(zai)耦合(he)超細活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)/微濾膜(mo)過(guo)(guo)(guo)程中(zhong)(zhong)的(de)(de)(de)作用(yong)表(biao)明(ming)，天然(ran)有(you)(you)(you)機(ji)(ji)物(wu)被證(zheng)明(ming)是(shi)膜(mo)污(wu)染和超細活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)的(de)(de)(de)主要原因，活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)實際上比單獨的(de)(de)(de)天然(ran)有(you)(you)(you)機(ji)(ji)物(wu)減(jian)少了結(jie)垢。然(ran)而(er)，一(yi)些(xie)研究(jiu)人員報告說(shuo)，活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)的(de)(de)(de)存在(zai)會加重膜(mo)污(wu)染或不影響膜(mo)通量(liang)。 在(zai)反洗(xi)水中(zhong)(zhong)發(fa)現活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)顆(ke)粒，因為它(ta)們(men)可(ke)能(neng)在(zai)污(wu)垢層的(de)(de)(de)生長過(guo)(guo)(guo)程中(zhong)(zhong)積(ji)累。活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)既(ji)不促進也不控制膜(mo)可(ke)逆結(jie)垢。

　　活(huo)性(xing)(xing)炭(tan)用(yong)于處理(li)(li)微濾(lv)膜(mo)(mo)前的預(yu)處理(li)(li)和地(di)表水(shui)(shui)。實(shi)驗(yan)的主要目的是研究活(huo)性(xing)(xing)炭(tan)對膜(mo)(mo)性(xing)(xing)能的影(ying)響，特(te)別(bie)關注(zhu)活(huo)性(xing)(xing)炭(tan)微濾(lv)膜(mo)(mo)工藝對有機(ji)物去除率和膜(mo)(mo)通量的影(ying)響。木質活(huo)性(xing)(xing)炭(tan)。粒度分布(bu)為(wei)：>74μm-71%，>44μm-95%。使用(yong)前，加入少量去離子水(shui)(shui)均(jun)勻化活(huo)性(xing)(xing)炭(tan)。在原水(shui)(shui)中加入10、50、100、200mg / L特(te)殊活(huo)性(xing)(xing)炭(tan)劑量。本(ben)實(shi)驗(yan)采(cai)用(yong)黃(huang)浦江地(di)表水(shui)(shui)。在水(shui)(shui)樣(yang)中加入活(huo)性(xing)(xing)炭(tan)100rpm快速攪拌30分鐘1分鐘，攪拌30分鐘rpm緩慢(man)混(hun)合，然(ran)后用(yong)0.45μm過(guo)濾(lv)器(qi)過(guo)濾(lv)水(shui)(shui)樣(yang)品(pin)(pin)。以下膜(mo)(mo)過(guo)濾(lv)用(yong)過(guo)濾(lv)水(shui)(shui)樣(yang)品(pin)(pin)。

　　溶解有機碳和活性(xing)炭和微濾過程(cheng)UV254去除率(lv)

　　活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)和UV如(ru)圖(tu)所示，254的效率(lv)。活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)溶(rong)(rong)解(jie)有(you)機碳(tan)(tan)(tan)去除(chu)(chu)率(lv)較(jiao)高(gao)。活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)劑量(liang)(liang)為10-2000 mg / L當溶(rong)(rong)解(jie)有(you)機碳(tan)(tan)(tan)的去除(chu)(chu)率(lv)從(cong)(cong)3開始.0%提高(gao)到59.8%。活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)吸附后，微(wei)濾膜(mo)過濾水樣，溶(rong)(rong)解(jie)有(you)機碳(tan)(tan)(tan)從(cong)(cong)21中(zhong)去除(chu)(chu)滲透(tou)物.1%穩定增(zeng)加到62.2%。然而，隨著活(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)劑量(liang)(liang)的增(zeng)加，微(wei)濾膜(mo)溶(rong)(rong)解(jie)有(you)機碳(tan)(tan)(tan)去除(chu)(chu)量(liang)(liang)略有(you)增(zeng)加。

　　與溶解有機(ji)碳(tan)相比，UV254去(qu)除(chu)率(lv)高(gao)(gao)。隨(sui)著活(huo)性炭(tan)(tan)(tan)劑(ji)量從100開始mg / L增加到200mg / L，超濾(lv)吸(xi)收去(qu)除(chu)率(lv)為10.1%增加到70.3%。與微(wei)濾(lv)過濾(lv)后溶解有機(ji)碳(tan)去(qu)除(chu)率(lv)相似，活(huo)性炭(tan)(tan)(tan)用量越高(gao)(gao)，微(wei)濾(lv)膜去(qu)除(chu)UV254越低。可溶解有機(ji)碳(tan)和活(huo)性炭(tan)(tan)(tan)UV254去(qu)除(chu)率(lv)高(gao)(gao)，活(huo)性炭(tan)(tan)(tan)含量高(gao)(gao)，膜可去(qu)除(chu)殘留有機(ji)物。

　　在上述研(yan)究中，活性(xing)炭(tan)具有(you)(you)較高(gao)的有(you)(you)機(ji)物(wu)去除率。然而，即使在200年(nian)mg / L活性(xing)炭(tan)高(gao)的劑(ji)量下，活性(xing)炭(tan)不能改善膜通量。原(yuan)水有(you)(you)機(ji)質的微濾濃度為2-7kDa，特別是3-5kDa。活性(xing)炭(tan)吸(xi)附的有(you)(you)機(ji)物(wu)濃度約為3kDa 水中有(you)(you)機(ji)物(wu)分子(zi)量。顯(xian)然，活性(xing)炭(tan)對水中有(you)(you)機(ji)物(wu)分子(zi)物(wu)質影響不大。

　　微濾膜(mo)(mo)(mo)過(guo)(guo)濾后(hou)原水(shui)(shui)(shui)(shui)(shui)的(de)(de)疏水(shui)(shui)(shui)(shui)(shui)性(xing)/親水(shui)(shui)(shui)(shui)(shui)性(xing)變化如圖6所示(shi)。可見(jian)，微濾膜(mo)(mo)(mo)主要去除(chu)疏水(shui)(shui)(shui)(shui)(shui)有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)。圖7顯(xian)(xian)示(shi)了原水(shui)(shui)(shui)(shui)(shui)中(zhong)不同水(shui)(shui)(shui)(shui)(shui)中(zhong)有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)分(fen)子(zi)量的(de)(de)疏水(shui)(shui)(shui)(shui)(shui)性(xing)/親水(shui)(shui)(shui)(shui)(shui)性(xing)變化。膜(mo)(mo)(mo)過(guo)(guo)濾后(hou)，疏水(shui)(shui)(shui)(shui)(shui)有(you)(you)(you)機(ji)(ji)(ji)質的(de)(de)比(bi)(bi)例(li)明顯(xian)(xian)下(xia)(xia)降，特別是2-7 kDa 有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)。相比(bi)(bi)之下(xia)(xia)，親水(shui)(shui)(shui)(shui)(shui)性(xing)有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)的(de)(de)比(bi)(bi)例(li)顯(xian)(xian)著(zhu)增加。本研究采(cai)用(yong)親水(shui)(shui)(shui)(shui)(shui)性(xing)PVDF膜(mo)(mo)(mo)。因此，疏水(shui)(shui)(shui)(shui)(shui)物(wu)(wu)質不能通過(guo)(guo)膜(mo)(mo)(mo)并停留在(zai)膜(mo)(mo)(mo)表面。親水(shui)(shui)(shui)(shui)(shui)性(xing)有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)容(rong)易通過(guo)(guo)膜(mo)(mo)(mo)，然后(hou)親水(shui)(shui)(shui)(shui)(shui)性(xing)有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)在(zai)滲透(tou)物(wu)(wu)中(zhong)的(de)(de)比(bi)(bi)例(li)顯(xian)(xian)著(zhu)增加。膜(mo)(mo)(mo)有(you)(you)(you)機(ji)(ji)(ji)污染物(wu)(wu)似乎是2-7kDa 疏水(shui)(shui)(shui)(shui)(shui)有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)是重點(dian)。活(huo)性(xing)炭(tan)僅部分(fen)吸附2-7 kDa 有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)，輕微促進膜(mo)(mo)(mo)污染。這是因為活(huo)性(xing)炭(tan)顯(xian)(xian)著(zhu)去除(chu)有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)，增強(qiang)膜(mo)(mo)(mo)通量。