活性炭對微濾膜的影響

　　活性(xing)(xing)(xing)炭(tan)吸(xi)(xi)(xi)附對微(wei)濾(lv)(lv)(lv)膜(mo)(mo)性(xing)(xing)(xing)能的影(ying)響。結(jie)果(guo)表明，活性(xing)(xing)(xing)炭(tan)預處理為10-200 mg / L 在(zai)劑(ji)量(liang)(liang)下，溶解有(you)(you)(you)機(ji)碳(DOC)和(he)254 nm紫外吸(xi)(xi)(xi)收光譜(UV 254)都(dou)能提供高有(you)(you)(you)機(ji)物(wu)去(qu)除(chu)率(lv)。通過(guo)MF隨著活性(xing)(xing)(xing)炭(tan)吸(xi)(xi)(xi)附有(you)(you)(you)機(ji)物(wu)的增加，膜(mo)(mo)過(guo)濾(lv)(lv)(lv)去(qu)除(chu)效(xiao)率(lv)降低。主要去(qu)除(chu)活性(xing)(xing)(xing)炭(tan)約3kDa有(you)(you)(you)機(ji)物(wu)質的分子量(liang)(liang)。活性(xing)(xing)(xing)炭(tan)吸(xi)(xi)(xi)附后，膜(mo)(mo)在(zai)膜(mo)(mo)上保持超(chao)過(guo)5kDa有(you)(you)(you)機(ji)物(wu)質。膜(mo)(mo)過(guo)濾(lv)(lv)(lv)結(jie)果(guo)表明，無論活性(xing)(xing)(xing)炭(tan)劑(ji)量(liang)(liang)如何(he)，活性(xing)(xing)(xing)炭(tan)的預處理都(dou)略微(wei)促進膜(mo)(mo)通量(liang)(liang)。似乎有(you)(you)(you)機(ji)污(wu)垢膜(mo)(mo)集(ji)中(zhong)在(zai)3以上kDa的微(wei)濾(lv)(lv)(lv)膜(mo)(mo)。活性(xing)(xing)(xing)炭(tan)去(qu)除(chu)明顯小(xiao)于33kDa 微(wei)濾(lv)(lv)(lv)膜(mo)(mo)有(you)(you)(you)機(ji)物(wu)超(chao)過(guo)3種kDa有(you)(you)(you)機(ji)物(wu)質的影(ying)響較小(xiao)。因此，活性(xing)(xing)(xing)炭(tan)不能減少膜(mo)(mo)污(wu)染。

　　膜(mo)污染是(shi)水處理(li)的(de)重要(yao)問題之一(yi)。膜(mo)結垢(gou)導致膜(mo)通(tong)量降低和性能差。一(yi)些研究表明，天然有(you)機(ji)物(NOM)負(fu)責炭(tan)吸(xi)附(fu)是(shi)飲用水中負(fu)責微濾膜(mo)污染或垢(gou)。活性炭(tan)吸(xi)附(fu)是(shi)減(jian)少有(you)機(ji)物污染膜(mo)的(de)好(hao)選(xuan)擇(ze)。

　　活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)廣泛用(yong)(yong)作水(shui)處(chu)理中(zhong)的(de)(de)(de)吸(xi)(xi)收劑(ji)。活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)具有(you)(you)良好的(de)(de)(de)天(tian)(tian)然(ran)有(you)(you)機物(wu)(wu)吸(xi)(xi)附性(xing)(xing)能(neng)，因(yin)此采用(yong)(yong)預處(chu)理，減少(shao)膜(mo)(mo)污(wu)染(ran)，提(ti)(ti)高(gao)膜(mo)(mo)性(xing)(xing)能(neng)。然(ran)而(er)(er)，活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)對提(ti)(ti)高(gao)膜(mo)(mo)性(xing)(xing)能(neng)的(de)(de)(de)效率(lv)有(you)(you)不(bu)同的(de)(de)(de)結論(lun)。一(yi)些(xie)研(yan)究表(biao)明，當活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)保持膜(mo)(mo)表(biao)面時，活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)可(ke)以(yi)增(zeng)強膜(mo)(mo)通(tong)量 。活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)懸浮在活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)/超(chao)濾(lv)系統中(zhong)的(de)(de)(de)作用(yong)(yong)是吸(xi)(xi)收低分(fen)子腐殖酸(HA)。膜(mo)(mo)提(ti)(ti)供物(wu)(wu)理屏障，防(fang)止活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)通(tong)過(guo)，從而(er)(er)保留吸(xi)(xi)附在活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)上的(de)(de)(de)有(you)(you)機化合(he)物(wu)(wu)。發現(xian)活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)可(ke)能(neng)導致更(geng)大的(de)(de)(de)絮凝顆(ke)粒(li)，并通(tong)過(guo)預處(chu)理活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)來減少(shao)每個過(guo)濾(lv)周期的(de)(de)(de)可(ke)逆性(xing)(xing)TMP增(zeng)加。研(yan)究天(tian)(tian)然(ran)有(you)(you)機物(wu)(wu)在耦合(he)超(chao)細(xi)活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)/微濾(lv)膜(mo)(mo)過(guo)程中(zhong)的(de)(de)(de)作用(yong)(yong)表(biao)明，天(tian)(tian)然(ran)有(you)(you)機物(wu)(wu)被(bei)證明是膜(mo)(mo)污(wu)染(ran)和超(chao)細(xi)活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)主要原因(yin)，活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)實(shi)際上比單(dan)獨的(de)(de)(de)天(tian)(tian)然(ran)有(you)(you)機物(wu)(wu)減少(shao)了結垢。然(ran)而(er)(er)，一(yi)些(xie)研(yan)究人員報告(gao)說，活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)(de)存在會加重膜(mo)(mo)污(wu)染(ran)或不(bu)影響膜(mo)(mo)通(tong)量。 在反洗水(shui)中(zhong)發現(xian)活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)顆(ke)粒(li)，因(yin)為它們可(ke)能(neng)在污(wu)垢層的(de)(de)(de)生長(chang)過(guo)程中(zhong)積累。活(huo)(huo)性(xing)(xing)炭(tan)(tan)(tan)(tan)既不(bu)促進也不(bu)控制膜(mo)(mo)可(ke)逆結垢。

　　活(huo)性(xing)(xing)炭用(yong)于處(chu)理(li)微濾(lv)膜(mo)(mo)(mo)前的(de)預處(chu)理(li)和地表水。實驗(yan)的(de)主要目的(de)是(shi)研究活(huo)性(xing)(xing)炭對膜(mo)(mo)(mo)性(xing)(xing)能的(de)影(ying)響(xiang)，特別關注活(huo)性(xing)(xing)炭微濾(lv)膜(mo)(mo)(mo)工藝對有機物去(qu)(qu)除率和膜(mo)(mo)(mo)通量(liang)(liang)的(de)影(ying)響(xiang)。木質活(huo)性(xing)(xing)炭。粒度分(fen)布為：>74μm-71%，>44μm-95%。使用(yong)前，加(jia)入少量(liang)(liang)去(qu)(qu)離子水均勻化活(huo)性(xing)(xing)炭。在原(yuan)水中加(jia)入10、50、100、200mg / L特殊(shu)活(huo)性(xing)(xing)炭劑量(liang)(liang)。本實驗(yan)采用(yong)黃浦江地表水。在水樣中加(jia)入活(huo)性(xing)(xing)炭100rpm快速攪拌30分(fen)鐘(zhong)(zhong)1分(fen)鐘(zhong)(zhong)，攪拌30分(fen)鐘(zhong)(zhong)rpm緩慢(man)混(hun)合，然后用(yong)0.45μm過濾(lv)器過濾(lv)水樣品。以下膜(mo)(mo)(mo)過濾(lv)用(yong)過濾(lv)水樣品。

　　溶解有機碳和活性炭和微濾過程UV254去除率

　　活(huo)(huo)性(xing)炭和UV如圖(tu)所示，254的(de)效率(lv)(lv)。活(huo)(huo)性(xing)炭溶解(jie)(jie)有(you)機碳(tan)(tan)去(qu)除率(lv)(lv)較高。活(huo)(huo)性(xing)炭劑(ji)量為(wei)10-2000 mg / L當溶解(jie)(jie)有(you)機碳(tan)(tan)的(de)去(qu)除率(lv)(lv)從(cong)3開始.0%提高到59.8%。活(huo)(huo)性(xing)炭吸附后，微(wei)(wei)濾膜過(guo)濾水(shui)樣，溶解(jie)(jie)有(you)機碳(tan)(tan)從(cong)21中(zhong)去(qu)除滲(shen)透(tou)物.1%穩定增(zeng)加到62.2%。然(ran)而，隨著(zhu)活(huo)(huo)性(xing)炭劑(ji)量的(de)增(zeng)加，微(wei)(wei)濾膜溶解(jie)(jie)有(you)機碳(tan)(tan)去(qu)除量略有(you)增(zeng)加。

　　與溶(rong)解有(you)機碳相比，UV254去(qu)除率(lv)高。隨著活性(xing)(xing)炭(tan)劑量從100開始mg / L增加(jia)到(dao)200mg / L，超濾吸收(shou)去(qu)除率(lv)為10.1%增加(jia)到(dao)70.3%。與微(wei)濾過濾后(hou)溶(rong)解有(you)機碳去(qu)除率(lv)相似，活性(xing)(xing)炭(tan)用量越高，微(wei)濾膜去(qu)除UV254越低(di)。可溶(rong)解有(you)機碳和(he)活性(xing)(xing)炭(tan)UV254去(qu)除率(lv)高，活性(xing)(xing)炭(tan)含量高，膜可去(qu)除殘留有(you)機物。

　　在上述研究中(zhong)，活(huo)性(xing)炭(tan)具有(you)較(jiao)高的(de)有(you)機(ji)物去(qu)除率(lv)。然而，即使在200年mg / L活(huo)性(xing)炭(tan)高的(de)劑量下(xia)，活(huo)性(xing)炭(tan)不能改善膜通(tong)量。原水(shui)有(you)機(ji)質的(de)微(wei)濾(lv)濃度為(wei)(wei)2-7kDa，特(te)別是(shi)3-5kDa。活(huo)性(xing)炭(tan)吸附的(de)有(you)機(ji)物濃度約為(wei)(wei)3kDa 水(shui)中(zhong)有(you)機(ji)物分子量。顯然，活(huo)性(xing)炭(tan)對水(shui)中(zhong)有(you)機(ji)物分子物質影(ying)響不大。

　　微濾膜(mo)(mo)(mo)(mo)過(guo)濾后(hou)原(yuan)水(shui)(shui)(shui)(shui)(shui)的(de)疏(shu)(shu)水(shui)(shui)(shui)(shui)(shui)性(xing)(xing)(xing)/親(qin)(qin)(qin)(qin)水(shui)(shui)(shui)(shui)(shui)性(xing)(xing)(xing)變化(hua)(hua)如圖6所示。可見，微濾膜(mo)(mo)(mo)(mo)主(zhu)要去除疏(shu)(shu)水(shui)(shui)(shui)(shui)(shui)有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)物(wu)(wu)。圖7顯(xian)示了(le)原(yuan)水(shui)(shui)(shui)(shui)(shui)中(zhong)不同(tong)水(shui)(shui)(shui)(shui)(shui)中(zhong)有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)物(wu)(wu)分(fen)子量(liang)的(de)疏(shu)(shu)水(shui)(shui)(shui)(shui)(shui)性(xing)(xing)(xing)/親(qin)(qin)(qin)(qin)水(shui)(shui)(shui)(shui)(shui)性(xing)(xing)(xing)變化(hua)(hua)。膜(mo)(mo)(mo)(mo)過(guo)濾后(hou)，疏(shu)(shu)水(shui)(shui)(shui)(shui)(shui)有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)質的(de)比(bi)例(li)明顯(xian)下(xia)降，特(te)別是(shi)(shi)2-7 kDa 有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)物(wu)(wu)。相比(bi)之下(xia)，親(qin)(qin)(qin)(qin)水(shui)(shui)(shui)(shui)(shui)性(xing)(xing)(xing)有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)物(wu)(wu)的(de)比(bi)例(li)顯(xian)著增加。本研究采用親(qin)(qin)(qin)(qin)水(shui)(shui)(shui)(shui)(shui)性(xing)(xing)(xing)PVDF膜(mo)(mo)(mo)(mo)。因(yin)此，疏(shu)(shu)水(shui)(shui)(shui)(shui)(shui)物(wu)(wu)質不能(neng)通過(guo)膜(mo)(mo)(mo)(mo)并停(ting)留在膜(mo)(mo)(mo)(mo)表面。親(qin)(qin)(qin)(qin)水(shui)(shui)(shui)(shui)(shui)性(xing)(xing)(xing)有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)物(wu)(wu)容(rong)易通過(guo)膜(mo)(mo)(mo)(mo)，然后(hou)親(qin)(qin)(qin)(qin)水(shui)(shui)(shui)(shui)(shui)性(xing)(xing)(xing)有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)物(wu)(wu)在滲透物(wu)(wu)中(zhong)的(de)比(bi)例(li)顯(xian)著增加。膜(mo)(mo)(mo)(mo)有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)污(wu)染(ran)物(wu)(wu)似乎(hu)是(shi)(shi)2-7kDa 疏(shu)(shu)水(shui)(shui)(shui)(shui)(shui)有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)物(wu)(wu)是(shi)(shi)重(zhong)點。活性(xing)(xing)(xing)炭(tan)僅部分(fen)吸附2-7 kDa 有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)物(wu)(wu)，輕微促進(jin)膜(mo)(mo)(mo)(mo)污(wu)染(ran)。這(zhe)是(shi)(shi)因(yin)為活性(xing)(xing)(xing)炭(tan)顯(xian)著去除有(you)(you)(you)機(ji)(ji)(ji)(ji)(ji)物(wu)(wu)，增強(qiang)膜(mo)(mo)(mo)(mo)通量(liang)。