活性炭對微濾膜的影響

　　活(huo)(huo)性(xing)炭(tan)吸附(fu)對微(wei)濾(lv)膜(mo)性(xing)能的影(ying)響。結果(guo)表(biao)明，活(huo)(huo)性(xing)炭(tan)預(yu)(yu)處理(li)為10-200 mg / L 在劑量(liang)下，溶解有(you)(you)(you)機(ji)碳(DOC)和(he)254 nm紫外吸收光譜(pu)(UV 254)都能提供高有(you)(you)(you)機(ji)物(wu)(wu)去除(chu)率。通過MF隨著活(huo)(huo)性(xing)炭(tan)吸附(fu)有(you)(you)(you)機(ji)物(wu)(wu)的增加，膜(mo)過濾(lv)去除(chu)效率降低。主要去除(chu)活(huo)(huo)性(xing)炭(tan)約(yue)3kDa有(you)(you)(you)機(ji)物(wu)(wu)質的分(fen)子量(liang)。活(huo)(huo)性(xing)炭(tan)吸附(fu)后(hou)，膜(mo)在膜(mo)上保持超過5kDa有(you)(you)(you)機(ji)物(wu)(wu)質。膜(mo)過濾(lv)結果(guo)表(biao)明，無論活(huo)(huo)性(xing)炭(tan)劑量(liang)如(ru)何，活(huo)(huo)性(xing)炭(tan)的預(yu)(yu)處理(li)都略微(wei)促進(jin)膜(mo)通量(liang)。似(si)乎有(you)(you)(you)機(ji)污(wu)垢膜(mo)集中(zhong)在3以(yi)上kDa的微(wei)濾(lv)膜(mo)。活(huo)(huo)性(xing)炭(tan)去除(chu)明顯小(xiao)于33kDa 微(wei)濾(lv)膜(mo)有(you)(you)(you)機(ji)物(wu)(wu)超過3種kDa有(you)(you)(you)機(ji)物(wu)(wu)質的影(ying)響較小(xiao)。因此，活(huo)(huo)性(xing)炭(tan)不(bu)能減少(shao)膜(mo)污(wu)染。

　　膜污染(ran)(ran)是水(shui)處理的(de)重要問(wen)題之一。膜結(jie)垢導致膜通量降(jiang)低和(he)性(xing)能差。一些研究表明，天然有機(ji)物(NOM)負責炭(tan)吸附(fu)是飲用水(shui)中負責微(wei)濾(lv)膜污染(ran)(ran)或垢。活性(xing)炭(tan)吸附(fu)是減(jian)少有機(ji)物污染(ran)(ran)膜的(de)好選擇。

　　活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)廣泛用作(zuo)水處理中的(de)吸(xi)收劑。活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)具有(you)(you)(you)良好的(de)天(tian)然(ran)有(you)(you)(you)機(ji)物吸(xi)附性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)，因此采(cai)用預(yu)處理，減少膜(mo)(mo)(mo)污(wu)染，提高膜(mo)(mo)(mo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)。然(ran)而，活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)對(dui)提高膜(mo)(mo)(mo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)能(neng)的(de)效(xiao)率有(you)(you)(you)不(bu)(bu)同的(de)結論(lun)。一些(xie)研究(jiu)表明，當活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)保(bao)持膜(mo)(mo)(mo)表面時(shi)，活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)可以增(zeng)強膜(mo)(mo)(mo)通量(liang) 。活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)懸浮在活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)/超濾系(xi)統中的(de)作(zuo)用是吸(xi)收低分(fen)子(zi)腐殖酸(suan)(HA)。膜(mo)(mo)(mo)提供物理屏障，防止活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)通過(guo)，從而保(bao)留吸(xi)附在活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)上(shang)的(de)有(you)(you)(you)機(ji)化合(he)物。發現活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)可能(neng)導(dao)致(zhi)更大(da)的(de)絮(xu)凝顆粒，并通過(guo)預(yu)處理活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)來(lai)減少每個過(guo)濾周期的(de)可逆性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)TMP增(zeng)加。研究(jiu)天(tian)然(ran)有(you)(you)(you)機(ji)物在耦合(he)超細活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)/微濾膜(mo)(mo)(mo)過(guo)程中的(de)作(zuo)用表明，天(tian)然(ran)有(you)(you)(you)機(ji)物被證明是膜(mo)(mo)(mo)污(wu)染和超細活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)的(de)主要原(yuan)因，活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)實際(ji)上(shang)比(bi)單獨的(de)天(tian)然(ran)有(you)(you)(you)機(ji)物減少了結垢。然(ran)而，一些(xie)研究(jiu)人員報(bao)告說(shuo)，活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)的(de)存在會加重膜(mo)(mo)(mo)污(wu)染或不(bu)(bu)影響膜(mo)(mo)(mo)通量(liang)。 在反洗(xi)水中發現活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)顆粒，因為它們可能(neng)在污(wu)垢層的(de)生(sheng)長過(guo)程中積累。活(huo)(huo)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)炭(tan)(tan)既不(bu)(bu)促進也(ye)不(bu)(bu)控制膜(mo)(mo)(mo)可逆結垢。

　　活(huo)(huo)性(xing)炭用于(yu)處理(li)微濾膜前(qian)的(de)(de)預處理(li)和地(di)表水(shui)。實驗的(de)(de)主(zhu)要目的(de)(de)是(shi)研究活(huo)(huo)性(xing)炭對膜性(xing)能的(de)(de)影響，特(te)別關注活(huo)(huo)性(xing)炭微濾膜工藝(yi)對有機物(wu)去除率和膜通量的(de)(de)影響。木質活(huo)(huo)性(xing)炭。粒度分(fen)(fen)布為：>74μm-71%，>44μm-95%。使用前(qian)，加入少量去離(li)子水(shui)均勻化活(huo)(huo)性(xing)炭。在原水(shui)中加入10、50、100、200mg / L特(te)殊活(huo)(huo)性(xing)炭劑量。本實驗采用黃浦江(jiang)地(di)表水(shui)。在水(shui)樣中加入活(huo)(huo)性(xing)炭100rpm快(kuai)速攪拌30分(fen)(fen)鐘1分(fen)(fen)鐘，攪拌30分(fen)(fen)鐘rpm緩慢(man)混合，然后用0.45μm過濾器過濾水(shui)樣品。以(yi)下(xia)膜過濾用過濾水(shui)樣品。

　　溶解有(you)機碳(tan)和(he)活性炭和(he)微濾過程UV254去除(chu)率

　　活(huo)性炭(tan)(tan)和UV如(ru)圖所示(shi)，254的效率(lv)。活(huo)性炭(tan)(tan)溶(rong)解(jie)有(you)(you)機(ji)碳(tan)去(qu)(qu)除率(lv)較高(gao)。活(huo)性炭(tan)(tan)劑量(liang)為10-2000 mg / L當溶(rong)解(jie)有(you)(you)機(ji)碳(tan)的去(qu)(qu)除率(lv)從3開(kai)始(shi).0%提高(gao)到59.8%。活(huo)性炭(tan)(tan)吸(xi)附后，微濾(lv)膜(mo)過(guo)濾(lv)水(shui)樣，溶(rong)解(jie)有(you)(you)機(ji)碳(tan)從21中去(qu)(qu)除滲(shen)透(tou)物.1%穩定增(zeng)加(jia)到62.2%。然而(er)，隨著活(huo)性炭(tan)(tan)劑量(liang)的增(zeng)加(jia)，微濾(lv)膜(mo)溶(rong)解(jie)有(you)(you)機(ji)碳(tan)去(qu)(qu)除量(liang)略有(you)(you)增(zeng)加(jia)。

　　與(yu)溶(rong)解(jie)有(you)機碳(tan)相比(bi)，UV254去除(chu)(chu)率(lv)高(gao)(gao)。隨(sui)著活性炭(tan)劑量從100開(kai)始mg / L增(zeng)加(jia)到200mg / L，超濾(lv)(lv)吸(xi)收去除(chu)(chu)率(lv)為10.1%增(zeng)加(jia)到70.3%。與(yu)微濾(lv)(lv)過濾(lv)(lv)后溶(rong)解(jie)有(you)機碳(tan)去除(chu)(chu)率(lv)相似(si)，活性炭(tan)用量越(yue)高(gao)(gao)，微濾(lv)(lv)膜(mo)(mo)去除(chu)(chu)UV254越(yue)低(di)。可(ke)溶(rong)解(jie)有(you)機碳(tan)和活性炭(tan)UV254去除(chu)(chu)率(lv)高(gao)(gao)，活性炭(tan)含量高(gao)(gao)，膜(mo)(mo)可(ke)去除(chu)(chu)殘留有(you)機物(wu)。

　　在(zai)上(shang)述(shu)研究中(zhong)，活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)具有較高的有機(ji)物(wu)(wu)去除(chu)率(lv)。然而，即(ji)使在(zai)200年mg / L活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)高的劑量下(xia)，活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)不(bu)能改(gai)善膜通量。原水有機(ji)質的微濾濃度(du)為(wei)2-7kDa，特別是(shi)3-5kDa。活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)吸附(fu)的有機(ji)物(wu)(wu)濃度(du)約為(wei)3kDa 水中(zhong)有機(ji)物(wu)(wu)分(fen)子量。顯然，活(huo)性(xing)(xing)(xing)(xing)炭(tan)(tan)對水中(zhong)有機(ji)物(wu)(wu)分(fen)子物(wu)(wu)質影響(xiang)不(bu)大。

　　微(wei)濾(lv)膜(mo)過濾(lv)后原(yuan)水(shui)(shui)(shui)的(de)(de)疏(shu)(shu)水(shui)(shui)(shui)性(xing)(xing)(xing)/親水(shui)(shui)(shui)性(xing)(xing)(xing)變(bian)(bian)化(hua)(hua)如圖(tu)6所示。可見，微(wei)濾(lv)膜(mo)主(zhu)要去除疏(shu)(shu)水(shui)(shui)(shui)有(you)(you)機(ji)(ji)物(wu)(wu)(wu)。圖(tu)7顯示了原(yuan)水(shui)(shui)(shui)中不(bu)同水(shui)(shui)(shui)中有(you)(you)機(ji)(ji)物(wu)(wu)(wu)分子(zi)量的(de)(de)疏(shu)(shu)水(shui)(shui)(shui)性(xing)(xing)(xing)/親水(shui)(shui)(shui)性(xing)(xing)(xing)變(bian)(bian)化(hua)(hua)。膜(mo)過濾(lv)后，疏(shu)(shu)水(shui)(shui)(shui)有(you)(you)機(ji)(ji)質的(de)(de)比例(li)明顯下降，特(te)別是2-7 kDa 有(you)(you)機(ji)(ji)物(wu)(wu)(wu)。相比之(zhi)下，親水(shui)(shui)(shui)性(xing)(xing)(xing)有(you)(you)機(ji)(ji)物(wu)(wu)(wu)的(de)(de)比例(li)顯著增(zeng)加(jia)。本研究采用(yong)親水(shui)(shui)(shui)性(xing)(xing)(xing)PVDF膜(mo)。因此，疏(shu)(shu)水(shui)(shui)(shui)物(wu)(wu)(wu)質不(bu)能(neng)通過膜(mo)并停留在膜(mo)表面。親水(shui)(shui)(shui)性(xing)(xing)(xing)有(you)(you)機(ji)(ji)物(wu)(wu)(wu)容易通過膜(mo)，然后親水(shui)(shui)(shui)性(xing)(xing)(xing)有(you)(you)機(ji)(ji)物(wu)(wu)(wu)在滲透物(wu)(wu)(wu)中的(de)(de)比例(li)顯著增(zeng)加(jia)。膜(mo)有(you)(you)機(ji)(ji)污染物(wu)(wu)(wu)似(si)乎是2-7kDa 疏(shu)(shu)水(shui)(shui)(shui)有(you)(you)機(ji)(ji)物(wu)(wu)(wu)是重點(dian)。活性(xing)(xing)(xing)炭僅部分吸附2-7 kDa 有(you)(you)機(ji)(ji)物(wu)(wu)(wu)，輕(qing)微(wei)促進膜(mo)污染。這(zhe)是因為活性(xing)(xing)(xing)炭顯著去除有(you)(you)機(ji)(ji)物(wu)(wu)(wu)，增(zeng)強膜(mo)通量。