活性炭對微濾膜的影響

　　活(huo)性(xing)(xing)炭(tan)(tan)(tan)吸(xi)(xi)附(fu)對(dui)微(wei)(wei)濾膜(mo)(mo)(mo)(mo)(mo)性(xing)(xing)能(neng)的(de)影響(xiang)。結果表明(ming)，活(huo)性(xing)(xing)炭(tan)(tan)(tan)預處理為10-200 mg / L 在劑量(liang)(liang)下，溶解有(you)(you)機(ji)碳(DOC)和254 nm紫(zi)外吸(xi)(xi)收(shou)光譜(pu)(UV 254)都(dou)能(neng)提供高有(you)(you)機(ji)物(wu)(wu)(wu)去(qu)(qu)(qu)除率(lv)。通(tong)過(guo)MF隨著活(huo)性(xing)(xing)炭(tan)(tan)(tan)吸(xi)(xi)附(fu)有(you)(you)機(ji)物(wu)(wu)(wu)的(de)增(zeng)加，膜(mo)(mo)(mo)(mo)(mo)過(guo)濾去(qu)(qu)(qu)除效率(lv)降低。主要去(qu)(qu)(qu)除活(huo)性(xing)(xing)炭(tan)(tan)(tan)約(yue)3kDa有(you)(you)機(ji)物(wu)(wu)(wu)質(zhi)的(de)分子量(liang)(liang)。活(huo)性(xing)(xing)炭(tan)(tan)(tan)吸(xi)(xi)附(fu)后(hou)，膜(mo)(mo)(mo)(mo)(mo)在膜(mo)(mo)(mo)(mo)(mo)上保持超過(guo)5kDa有(you)(you)機(ji)物(wu)(wu)(wu)質(zhi)。膜(mo)(mo)(mo)(mo)(mo)過(guo)濾結果表明(ming)，無論活(huo)性(xing)(xing)炭(tan)(tan)(tan)劑量(liang)(liang)如何，活(huo)性(xing)(xing)炭(tan)(tan)(tan)的(de)預處理都(dou)略微(wei)(wei)促進膜(mo)(mo)(mo)(mo)(mo)通(tong)量(liang)(liang)。似(si)乎(hu)有(you)(you)機(ji)污垢(gou)膜(mo)(mo)(mo)(mo)(mo)集(ji)中在3以上kDa的(de)微(wei)(wei)濾膜(mo)(mo)(mo)(mo)(mo)。活(huo)性(xing)(xing)炭(tan)(tan)(tan)去(qu)(qu)(qu)除明(ming)顯(xian)小于33kDa 微(wei)(wei)濾膜(mo)(mo)(mo)(mo)(mo)有(you)(you)機(ji)物(wu)(wu)(wu)超過(guo)3種(zhong)kDa有(you)(you)機(ji)物(wu)(wu)(wu)質(zhi)的(de)影響(xiang)較小。因此，活(huo)性(xing)(xing)炭(tan)(tan)(tan)不能(neng)減少膜(mo)(mo)(mo)(mo)(mo)污染。

　　膜(mo)(mo)污(wu)染(ran)(ran)是(shi)水處理的重要問題(ti)之一(yi)。膜(mo)(mo)結垢(gou)導致膜(mo)(mo)通量降低和性能差。一(yi)些研究(jiu)表明，天然有機物(wu)(NOM)負責炭(tan)吸附(fu)(fu)是(shi)飲用水中(zhong)負責微濾(lv)膜(mo)(mo)污(wu)染(ran)(ran)或垢(gou)。活性炭(tan)吸附(fu)(fu)是(shi)減少有機物(wu)污(wu)染(ran)(ran)膜(mo)(mo)的好選擇。

　　活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)廣泛用(yong)(yong)(yong)作水(shui)處理(li)(li)中的(de)(de)吸收劑。活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)具有(you)(you)(you)良好的(de)(de)天然(ran)(ran)有(you)(you)(you)機(ji)(ji)(ji)物(wu)吸附性(xing)(xing)(xing)(xing)能(neng)(neng)，因(yin)此采用(yong)(yong)(yong)預處理(li)(li)，減(jian)少(shao)(shao)膜(mo)(mo)污(wu)(wu)染(ran)，提(ti)高膜(mo)(mo)性(xing)(xing)(xing)(xing)能(neng)(neng)。然(ran)(ran)而，活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)對(dui)提(ti)高膜(mo)(mo)性(xing)(xing)(xing)(xing)能(neng)(neng)的(de)(de)效率有(you)(you)(you)不同的(de)(de)結論。一些(xie)研(yan)究表明(ming)(ming)，當(dang)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)保持膜(mo)(mo)表面(mian)時，活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)可以增強膜(mo)(mo)通(tong)量 。活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)懸浮(fu)在(zai)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)/超(chao)(chao)濾(lv)系統(tong)中的(de)(de)作用(yong)(yong)(yong)是(shi)吸收低分(fen)子腐殖(zhi)酸(HA)。膜(mo)(mo)提(ti)供物(wu)理(li)(li)屏障，防止活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)通(tong)過，從而保留(liu)吸附在(zai)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)上(shang)的(de)(de)有(you)(you)(you)機(ji)(ji)(ji)化合物(wu)。發(fa)現活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)可能(neng)(neng)導致(zhi)更大的(de)(de)絮凝顆(ke)粒，并通(tong)過預處理(li)(li)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)來減(jian)少(shao)(shao)每個過濾(lv)周期(qi)的(de)(de)可逆性(xing)(xing)(xing)(xing)TMP增加。研(yan)究天然(ran)(ran)有(you)(you)(you)機(ji)(ji)(ji)物(wu)在(zai)耦合超(chao)(chao)細(xi)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)/微濾(lv)膜(mo)(mo)過程(cheng)中的(de)(de)作用(yong)(yong)(yong)表明(ming)(ming)，天然(ran)(ran)有(you)(you)(you)機(ji)(ji)(ji)物(wu)被(bei)證明(ming)(ming)是(shi)膜(mo)(mo)污(wu)(wu)染(ran)和(he)超(chao)(chao)細(xi)活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)主要原因(yin)，活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)實(shi)際上(shang)比單獨的(de)(de)天然(ran)(ran)有(you)(you)(you)機(ji)(ji)(ji)物(wu)減(jian)少(shao)(shao)了結垢(gou)。然(ran)(ran)而，一些(xie)研(yan)究人(ren)員報告說，活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)的(de)(de)存在(zai)會加重膜(mo)(mo)污(wu)(wu)染(ran)或不影響膜(mo)(mo)通(tong)量。 在(zai)反洗水(shui)中發(fa)現活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)顆(ke)粒，因(yin)為(wei)它們(men)可能(neng)(neng)在(zai)污(wu)(wu)垢(gou)層的(de)(de)生(sheng)長過程(cheng)中積累。活(huo)(huo)(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)(tan)(tan)既不促進也(ye)不控制膜(mo)(mo)可逆結垢(gou)。

　　活性(xing)(xing)炭(tan)(tan)(tan)用(yong)于處(chu)理(li)微濾(lv)膜(mo)前的(de)(de)預處(chu)理(li)和地表水。實驗(yan)的(de)(de)主(zhu)要目的(de)(de)是研(yan)究活性(xing)(xing)炭(tan)(tan)(tan)對膜(mo)性(xing)(xing)能的(de)(de)影(ying)響(xiang)，特(te)別關注活性(xing)(xing)炭(tan)(tan)(tan)微濾(lv)膜(mo)工(gong)藝對有機物去(qu)除率和膜(mo)通量(liang)的(de)(de)影(ying)響(xiang)。木(mu)質活性(xing)(xing)炭(tan)(tan)(tan)。粒度分(fen)(fen)布為：>74μm-71%，>44μm-95%。使(shi)用(yong)前，加(jia)(jia)入(ru)(ru)少量(liang)去(qu)離子水均勻化活性(xing)(xing)炭(tan)(tan)(tan)。在(zai)原水中(zhong)加(jia)(jia)入(ru)(ru)10、50、100、200mg / L特(te)殊(shu)活性(xing)(xing)炭(tan)(tan)(tan)劑量(liang)。本實驗(yan)采用(yong)黃浦江地表水。在(zai)水樣(yang)中(zhong)加(jia)(jia)入(ru)(ru)活性(xing)(xing)炭(tan)(tan)(tan)100rpm快速攪拌30分(fen)(fen)鐘(zhong)1分(fen)(fen)鐘(zhong)，攪拌30分(fen)(fen)鐘(zhong)rpm緩慢混合，然后用(yong)0.45μm過(guo)(guo)(guo)濾(lv)器過(guo)(guo)(guo)濾(lv)水樣(yang)品(pin)。以下膜(mo)過(guo)(guo)(guo)濾(lv)用(yong)過(guo)(guo)(guo)濾(lv)水樣(yang)品(pin)。

　　溶解有(you)機碳和(he)活性炭和(he)微濾過程UV254去除率

　　活(huo)性炭(tan)(tan)(tan)和UV如圖所示，254的(de)效(xiao)率。活(huo)性炭(tan)(tan)(tan)溶(rong)(rong)解有(you)機(ji)碳(tan)(tan)去(qu)除(chu)(chu)率較高(gao)。活(huo)性炭(tan)(tan)(tan)劑量為10-2000 mg / L當溶(rong)(rong)解有(you)機(ji)碳(tan)(tan)的(de)去(qu)除(chu)(chu)率從(cong)3開始.0%提(ti)高(gao)到59.8%。活(huo)性炭(tan)(tan)(tan)吸附后(hou)，微濾膜(mo)過濾水樣，溶(rong)(rong)解有(you)機(ji)碳(tan)(tan)從(cong)21中(zhong)去(qu)除(chu)(chu)滲透物.1%穩定增加到62.2%。然而，隨著活(huo)性炭(tan)(tan)(tan)劑量的(de)增加，微濾膜(mo)溶(rong)(rong)解有(you)機(ji)碳(tan)(tan)去(qu)除(chu)(chu)量略有(you)增加。

　　與溶(rong)(rong)解(jie)有(you)機(ji)碳相(xiang)(xiang)比，UV254去(qu)除(chu)(chu)率(lv)高(gao)(gao)。隨著(zhu)活性炭(tan)劑(ji)量從100開始(shi)mg / L增加到200mg / L，超濾吸收去(qu)除(chu)(chu)率(lv)為10.1%增加到70.3%。與微濾過濾后(hou)溶(rong)(rong)解(jie)有(you)機(ji)碳去(qu)除(chu)(chu)率(lv)相(xiang)(xiang)似，活性炭(tan)用量越(yue)高(gao)(gao)，微濾膜去(qu)除(chu)(chu)UV254越(yue)低。可(ke)溶(rong)(rong)解(jie)有(you)機(ji)碳和活性炭(tan)UV254去(qu)除(chu)(chu)率(lv)高(gao)(gao)，活性炭(tan)含量高(gao)(gao)，膜可(ke)去(qu)除(chu)(chu)殘留有(you)機(ji)物。

　　在上述研究中(zhong)(zhong)，活性(xing)(xing)炭(tan)具有(you)較高的(de)有(you)機物去除率。然(ran)而，即使在200年(nian)mg / L活性(xing)(xing)炭(tan)高的(de)劑量下，活性(xing)(xing)炭(tan)不能改善膜通(tong)量。原水(shui)有(you)機質的(de)微(wei)濾濃度為(wei)(wei)2-7kDa，特別是3-5kDa。活性(xing)(xing)炭(tan)吸附(fu)的(de)有(you)機物濃度約為(wei)(wei)3kDa 水(shui)中(zhong)(zhong)有(you)機物分(fen)子量。顯然(ran)，活性(xing)(xing)炭(tan)對水(shui)中(zhong)(zhong)有(you)機物分(fen)子物質影響不大。

　　微濾膜(mo)(mo)過(guo)(guo)濾后原水(shui)(shui)(shui)的(de)疏(shu)(shu)水(shui)(shui)(shui)性/親(qin)(qin)水(shui)(shui)(shui)性變(bian)化如(ru)圖6所示(shi)。可(ke)見，微濾膜(mo)(mo)主要去(qu)除(chu)疏(shu)(shu)水(shui)(shui)(shui)有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)。圖7顯示(shi)了原水(shui)(shui)(shui)中不同(tong)水(shui)(shui)(shui)中有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)分子量的(de)疏(shu)(shu)水(shui)(shui)(shui)性/親(qin)(qin)水(shui)(shui)(shui)性變(bian)化。膜(mo)(mo)過(guo)(guo)濾后，疏(shu)(shu)水(shui)(shui)(shui)有(you)(you)(you)機(ji)(ji)(ji)質的(de)比(bi)例明顯下降，特(te)別是(shi)(shi)2-7 kDa 有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)。相比(bi)之下，親(qin)(qin)水(shui)(shui)(shui)性有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)的(de)比(bi)例顯著增加。本研究采用親(qin)(qin)水(shui)(shui)(shui)性PVDF膜(mo)(mo)。因(yin)(yin)此，疏(shu)(shu)水(shui)(shui)(shui)物(wu)(wu)質不能通過(guo)(guo)膜(mo)(mo)并停留(liu)在膜(mo)(mo)表面(mian)。親(qin)(qin)水(shui)(shui)(shui)性有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)容易通過(guo)(guo)膜(mo)(mo)，然后親(qin)(qin)水(shui)(shui)(shui)性有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)在滲透(tou)物(wu)(wu)中的(de)比(bi)例顯著增加。膜(mo)(mo)有(you)(you)(you)機(ji)(ji)(ji)污染物(wu)(wu)似乎(hu)是(shi)(shi)2-7kDa 疏(shu)(shu)水(shui)(shui)(shui)有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)是(shi)(shi)重點。活(huo)性炭僅部分吸附2-7 kDa 有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)，輕微促進(jin)膜(mo)(mo)污染。這是(shi)(shi)因(yin)(yin)為活(huo)性炭顯著去(qu)除(chu)有(you)(you)(you)機(ji)(ji)(ji)物(wu)(wu)，增強膜(mo)(mo)通量。