常規組合工藝-穩定塘-濕地系統處理印染廢水
摘要:針對工業園區印染企業產生的印染廢(fei)水(shui)和(he)生活(huo)污水(shui),采用獨(du)特的“常(chang)規組合(he)工藝(yi)(yi)與(yu)‘植物穩定塘-人工濕地(di)系統(tong)’聯合(he)工藝(yi)(yi)”對其進行(xing)集中統(tong)一(yi)處理,并考察了(le)運(yun)行(xing)效(xiao)果。數據(ju)結果表(biao)明(ming),系統(tong)出水(shui)COD、BOD5、SS、色度(du)(du)、NH3-N和(he)TP平均(jun)(jun)分別(bie)為63.2 mg/L、13.8 mg/L、5.0 mg/L、49倍、0.2 mg/L和(he)0.4 mg/L,出水(shui)水(shui)質(zhi)達到(dao)國家污水(shui)綜合(he)排放(fang)一(yi)級標準(GB8978-1996)。該工藝(yi)(yi)運(yun)行(xing)穩定,可有效(xiao)去除(chu)廢(fei)水(shui)中的COD、SS和(he)色度(du)(du),去除(chu)率均(jun)(jun)在90%以上。按日均(jun)(jun)處理量4×104m3計算,此(ci)工藝(yi)(yi)每(mei)年將(jiang)削(xue)減COD排放(fang)近(jin)30萬t。
關鍵詞:物化 常規組合工藝 穩定(ding)塘 人工濕(shi)地(di) 印染廢水
紡織印(yin)染(ran)行業是用(yong)水(shui)和(he)排污大戶,2007年(nian)我國印(yin)染(ran)廢(fei)(fei)(fei)(fei)水(shui)年(nian)排放量已達(da)23~30億(yi)t,COD排放居(ju)工業領域(yu)第四[1]。印(yin)染(ran)廢(fei)(fei)(fei)(fei)水(shui)水(shui)量大、成分復(fu)雜、有機物濃度(du)(du)高、堿性大、色度(du)(du)高,且印(yin)染(ran)所采用(yong)的染(ran)料和(he)染(ran)整助劑分子結構十(shi)分復(fu)雜,廢(fei)(fei)(fei)(fei)水(shui)可生化性差,脫色難度(du)(du)大,是工業廢(fei)(fei)(fei)(fei)水(shui)處理(li)中的難題之一[1-4]。探索經濟有效(xiao)的印(yin)染(ran)廢(fei)(fei)(fei)(fei)水(shui)處理(li)方法(fa)成為近年(nian)來水(shui)處理(li)領域(yu)的熱點。
20世紀70年代以(yi)來(lai),國內(nei)處(chu)理(li)印染廢水(shui)主要以(yi)生(sheng)物(wu)(wu)處(chu)理(li)為主,尤(you)以(yi)好氧(yang)生(sheng)物(wu)(wu)處(chu)理(li)占絕大(da)多數[3]。但因印染行業中PVC、CWC和新(xin)型助劑(ji)等(deng)大(da)量使用(yong),染料也向(xiang)抗(kang)(kang)氧(yang)化、抗(kang)(kang)生(sheng)物(wu)(wu)降解方(fang)向(xiang)發(fa)展,導致印染廢水(shui)處(chu)理(li)難(nan)度大(da)增[5,6],單純用(yong)生(sheng)物(wu)(wu)工藝難(nan)以(yi)達標,物(wu)(wu)化法與生(sheng)化法結合起(qi)來(lai)成為趨(qu)勢[4,7-9]。
本(ben)工(gong)(gong)藝就采用了常規“物(wu)化和(he)(he)生化組合(he)”工(gong)(gong)藝,生化組合(he)是由厭氧水解酸化池和(he)(he)好氧活性污泥池組成(cheng)。除此之外,工(gong)(gong)藝還創新性地將(jiang)高效、低成(cheng)本(ben)的“植物(wu)穩定塘+人工(gong)(gong)濕地系(xi)統”工(gong)(gong)藝大(da)規模地應用于印染工(gong)(gong)業廢(fei)水的深(shen)度處理實踐中,具有(you)重(zhong)要的參考(kao)借(jie)鑒意義(yi)。
1·工程概況和分析方法
1.1原水水質(zhi)和(he)排放(fang)標(biao)準
廣東某印(yin)染(ran)污(wu)水(shui)處(chu)理(li)廠位于工業(ye)園(yuan)區紡(fang)(fang)織(zhi)染(ran)整(zheng)基地內(nei),集(ji)中統一處(chu)理(li)基地內(nei)數十(shi)家紡(fang)(fang)織(zhi)印(yin)染(ran)企業(ye)的工業(ye)廢(fei)(fei)(fei)水(shui)和生活(huo)污(wu)水(shui)。日均處(chu)理(li)印(yin)染(ran)廢(fei)(fei)(fei)水(shui)約4×104m3,主要包括漿料濃(nong)水(shui)、漂染(ran)廢(fei)(fei)(fei)水(shui)和印(yin)染(ran)助劑等印(yin)染(ran)廢(fei)(fei)(fei)水(shui)及部分(fen)生活(huo)污(wu)水(shui)。原水(shui)進水(shui)水(shui)質(zhi)和國家《污(wu)水(shui)綜合排(pai)放標(biao)準(zhun)》(GB8978-1996)一級標(biao)準(zhun)見表1。
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1.2工藝流(liu)程
根據(ju)綜合印(yin)染廢水(shui)污染物水(shui)量大(da)、成分復雜、色度(du)深和可生化(hua)(hua)性差等特點,采(cai)用生化(hua)(hua)-植物穩定塘-人(ren)工(gong)濕地系統工(gong)藝(yi)進(jin)行處(chu)理,其工(gong)藝(yi)流程(cheng)如圖1所示。
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1.3主(zhu)要構(gou)筑物
主要(yao)構筑物和設備如(ru)表2所示。
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1.3.1調節(jie)池
綜合印染廢水(shui)污(wu)染物(wu)種類多,成(cheng)分復雜(za)、性質不穩(wen)定,進水(shui)量(liang)大(da)且(qie)不穩(wen)定。調節池的作用就是通過預曝氣(qi)均(jun)(jun)化水(shui)量(liang)水(shui)質并(bing)加酸(suan)中和調節pH。為使污(wu)水(shui)水(shui)質均(jun)(jun)勻混合,其有效容積(ji)宜稍大(da),達到24 000m3。調節池出口處加入硫酸(suan)亞鐵(tie)、石灰乳,進入小型混合池后(hou),加PAM絮(xu)凝(ning)劑混凝(ning)沉淀,然后(hou)直接流進初沉池。
1.3.2厭氧水解(jie)池
采用厭氧(yang)(yang)水(shui)解(jie)酸化,廢(fei)水(shui)在(zai)厭氧(yang)(yang)水(shui)解(jie)酸化池(chi)內(nei)厭氧(yang)(yang)菌(jun)和產(chan)酸菌(jun)的(de)共同(tong)作用下,將廢(fei)水(shui)中結構復(fu)雜(za)的(de)大分(fen)子(zi)印染有機物(wu)(wu)降(jiang)解(jie)為小分(fen)子(zi)有機物(wu)(wu)或(huo)中間產(chan)物(wu)(wu),可(ke)降(jiang)低廢(fei)水(shui)毒性(xing)(xing)、提高廢(fei)水(shui)可(ke)生(sheng)化性(xing)(xing),為后續的(de)好(hao)氧(yang)(yang)活性(xing)(xing)污泥處理創造了條件。因廢(fei)水(shui)處理量大,應安裝攪拌器(qi),使池(chi)內(nei)的(de)微生(sheng)物(wu)(wu)與廢(fei)水(shui)均勻接(jie)觸,以(yi)更好(hao)地分(fen)解(jie)染料。
1.3.3好氧活(huo)性污泥池
活性污(wu)(wu)泥(ni)(ni)池(chi)在曝氣條件下,通過(guo)各(ge)種好氧細(xi)菌、原生生物(wu)和后生生物(wu)的(de)同化(hua)、異(yi)化(hua)作用,將印染(ran)廢水(shui)中的(de)有機(ji)物(wu)最終分(fen)解為(wei)水(shui)、二(er)(er)氧化(hua)碳和無機(ji)鹽。廢水(shui)經過(guo)活性污(wu)(wu)泥(ni)(ni)的(de)絮凝、吸附和降(jiang)解,再(zai)進入二(er)(er)沉池(chi)沉淀,排(pai)出(chu)上清(qing)液。二(er)(er)沉池(chi)的(de)部(bu)分(fen)污(wu)(wu)泥(ni)(ni)回(hui)流到活性污(wu)(wu)泥(ni)(ni)池(chi)。
1.3.4植物穩(wen)定(ding)塘(tang)-人工(gong)濕(shi)地
植(zhi)物(wu)穩(wen)定塘-人(ren)工濕(shi)地生(sheng)(sheng)態系(xi)統(tong)是將污(wu)水(shui)處理(li)廠7 km外的城郊荒(huang)地和(he)魚(yu)(yu)塘改建,改后系(xi)統(tong)由植(zhi)物(wu)穩(wen)定塘(2×4 000 m3)、三級串聯強化(hua)(hua)(hua)(hua)生(sheng)(sheng)物(wu)濾床(chuang)(3 500 m3+2 600 m3+4 900 m3)、表(biao)面溢流濕(shi)地(5 400 m3)、強化(hua)(hua)(hua)(hua)生(sheng)(sheng)物(wu)濾床(chuang)組(zu)成(6×5 000 m3),總占地面積約(yue)為(wei)5.5×104 m3。植(zhi)物(wu)穩(wen)定塘中栽(zai)有(you)蓮藕(ou)、水(shui)草,并放養鯉魚(yu)(yu)、草魚(yu)(yu)等,人(ren)工濕(shi)地的三級強化(hua)(hua)(hua)(hua)生(sheng)(sheng)物(wu)濾床(chuang)和(he)表(biao)面溢流濕(shi)地交叉種植(zhi)菖(chang)蒲、蘆葦、風(feng)車(che)草、美人(ren)蕉等對(dui)氮、磷(lin)、營養鹽(yan)類(lei)等具(ju)有(you)良好(hao)吸(xi)附(fu)降解作用的濕(shi)地植(zhi)物(wu),深(shen)度(du)去除廢水(shui)中SS、COD、氮磷(lin)和(he)色度(du)等主要污(wu)染物(wu)及(ji)其(qi)他微量特征污(wu)染物(wu),最后流入6個5 000 m3強化(hua)(hua)(hua)(hua)生(sheng)(sheng)物(wu)濾床(chuang)進一步(bu)深(shen)度(du)處理(li)降低(di)污(wu)染指標,經(jing)(jing)監測達(da)標后排入河涌。植(zhi)物(wu)穩(wen)定塘-人(ren)工濕(shi)地生(sheng)(sheng)態系(xi)統(tong)通過基質過濾、吸(xi)附(fu)、離子(zi)交換、植(zhi)物(wu)吸(xi)收和(he)微生(sheng)(sheng)物(wu)分解轉化(hua)(hua)(hua)(hua)等過程(cheng)來實現(xian)對(dui)污(wu)水(shui)的高效凈(jing)化(hua)(hua)(hua)(hua)具(ju)有(you)顯著的環境效益、良好(hao)的經(jing)(jing)濟效益[10]。
1.4分析方法(fa)
COD:重鉻酸鉀法(fa)測定(ding)(ding);BOD5:稀(xi)釋與接種法(fa)測定(ding)(ding);SS:重量法(fa)測定(ding)(ding);pH值:pH S-2型(xing)酸度(du)計測定(ding)(ding);色度(du):稀(xi)釋倍(bei)數法(fa)測定(ding)(ding);NH3-N:納氏試劑分光光度(du)法(fa)測定(ding)(ding);TP:過硫酸鉀消解-鉬(mu)銻抗壞血酸分光光度(du)法(fa)[11]。
2·運行結果與討論
2.1總體運行(xing)效果
該系統(tong)的生(sheng)(sheng)化(hua)(hua)工(gong)藝(yi)部分增加了水(shui)(shui)解酸化(hua)(hua)池后,對整個(ge)工(gong)程包(bao)括穩(wen)定(ding)(ding)(ding)塘、人工(gong)濕(shi)地(di)(di)系統(tong)(生(sheng)(sheng)化(hua)(hua)工(gong)藝(yi)改良(liang)之前已正常穩(wen)定(ding)(ding)(ding)運(yun)(yun)(yun)行(xing)(xing)(xing)(xing)1年左(zuo)右)在(zai)內進行(xing)(xing)(xing)(xing)了為期半(ban)年以上的調(diao)(diao)試(shi)(shi)運(yun)(yun)(yun)行(xing)(xing)(xing)(xing),工(gong)藝(yi)運(yun)(yun)(yun)行(xing)(xing)(xing)(xing)穩(wen)定(ding)(ding)(ding)、出水(shui)(shui)效果良(liang)好。如表3所(suo)示(shi),6—12月(yue)調(diao)(diao)試(shi)(shi)期間(jian)系統(tong)出水(shui)(shui)COD平(ping)均約63.2 mg/L,BOD513.8 mg/L,SS 5.0 mg/L,色度49倍,NH3-N 0.2 mg/L,TP 0.4 mg/L,完全符(fu)合GB8978-1996要求。盡管運(yun)(yun)(yun)行(xing)(xing)(xing)(xing)調(diao)(diao)試(shi)(shi)的半(ban)年期間(jian)有(you)相(xiang)當長時間(jian)處于氣溫較(jiao)低的秋(qiu)冬季(ji),但出水(shui)(shui)指(zhi)(zhi)標(biao)良(liang)好,基本(ben)沒有(you)超標(biao)現象。因廣東地(di)(di)處亞(ya)熱帶季(ji)風氣候(hou)區,全年平(ping)均氣溫22.2℃,氣溫的日較(jiao)差年較(jiao)差小(xiao),系統(tong)工(gong)藝(yi)受氣候(hou)影響較(jiao)小(xiao),因此(ci)為詳(xiang)細(xi)研究(jiu)工(gong)藝(yi)每(mei)日的運(yun)(yun)(yun)行(xing)(xing)(xing)(xing)情況(kuang),2.2~2.5節中(zhong)選取了處于調(diao)(diao)試(shi)(shi)運(yun)(yun)(yun)行(xing)(xing)(xing)(xing)穩(wen)定(ding)(ding)(ding)階段且氣候(hou)上具有(you)一(yi)定(ding)(ding)(ding)代表意義的10月(yue)和11月(yue)對各個(ge)水(shui)(shui)質指(zhi)(zhi)標(biao)進行(xing)(xing)(xing)(xing)了較(jiao)為詳(xiang)細(xi)的分析。
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2.2對(dui)COD的去除效(xiao)果
如圖2所示,穩(wen)(wen)定(ding)(ding)運行后(hou)系(xi)統(tong)(tong)進水(shui)量在3.0×104~4.3×104m3/d浮動,平(ping)均(jun)(jun)3.6×104 m3/d。進水(shui)COD 1 670~2 230 mg/L,平(ping)均(jun)(jun)2 024 mg/L,常(chang)規(gui)物(wu)化+生(sheng)化組合段工(gong)藝(yi)出(chu)水(shui)COD 89.6~125.4mg/L,平(ping)均(jun)(jun)108.2 mg/L,平(ping)均(jun)(jun)去(qu)除(chu)率(lv)94.6%。經植(zhi)(zhi)物(wu)穩(wen)(wen)定(ding)(ding)塘-人(ren)(ren)工(gong)濕(shi)地系(xi)統(tong)(tong)處理后(hou),出(chu)水(shui)COD 56.4~73.7 mg/L,平(ping)均(jun)(jun)64.6 mg/L,完全符合GB8978-1996一級標(biao)準,平(ping)均(jun)(jun)去(qu)除(chu)率(lv)為41.2%。可(ke)見植(zhi)(zhi)物(wu)穩(wen)(wen)定(ding)(ding)塘-人(ren)(ren)工(gong)濕(shi)地系(xi)統(tong)(tong)對工(gong)業廢水(shui)有較強的去(qu)除(chu)效果。同時,圖中進水(shui)COD曲(qu)線浮動范圍較大,但(dan)出(chu)水(shui)COD曲(qu)線始終(zhong)維持在100 mg/L左(zuo)右,說明常(chang)規(gui)物(wu)化+生(sheng)化組合段工(gong)藝(yi)去(qu)除(chu)效果穩(wen)(wen)定(ding)(ding),耐沖擊負荷大;再經植(zhi)(zhi)物(wu)穩(wen)(wen)定(ding)(ding)塘-人(ren)(ren)工(gong)濕(shi)地系(xi)統(tong)(tong)處理后(hou)的出(chu)水(shui)COD曲(qu)線接近直線,COD總去(qu)除(chu)率(lv)達(da)96%以上。
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2.3對SS的去除效果(guo)
系統穩(wen)定運(yun)行后(hou)(hou)的進(jin)水(shui)(shui)(shui)SS和去(qu)除效果如圖3所示,進(jin)水(shui)(shui)(shui)SS波動(dong)(dong)曲線(xian)上下浮動(dong)(dong)顯著。其中,前(qian)40天(tian)進(jin)水(shui)(shui)(shui)SS主(zhu)要(yao)在617~1 140 mg/L波動(dong)(dong),極(ji)差(cha)(cha)513mg/L,平(ping)均830 mg/L;后(hou)(hou)40天(tian)進(jin)水(shui)(shui)(shui)SS波動(dong)(dong)更為(wei)明(ming)顯,浮動(dong)(dong)在727~1 300 mg/L,極(ji)差(cha)(cha)達(da)573 mg/L,平(ping)均1 120 mg/L;前(qian)后(hou)(hou)兩階段平(ping)均值極(ji)差(cha)(cha)已達(da)290 mg/L。這主(zhu)要(yao)跟紡織企業的運(yun)行情況相關,因為(wei)工(gong)藝運(yun)行階段紡織出口受國際(ji)經(jing)濟(ji)形(xing)勢影響,訂單來源不(bu)穩(wen)定,導致(zhi)污水(shui)(shui)(shui)排(pai)放的水(shui)(shui)(shui)質水(shui)(shui)(shui)量(liang)變化(hua)顯著。盡管如此(ci),經(jing)過常規物化(hua)+生化(hua)組合工(gong)藝處理后(hou)(hou),出水(shui)(shui)(shui)SS保持穩(wen)定,10 mg/L左右(you),遠(yuan)低于GB8978-1996一級標準(zhun)70 mg/L,平(ping)均去(qu)除率(lv)達(da)到(dao)98.6%。經(jing)植物穩(wen)定塘-人(ren)工(gong)濕地系統進(jin)一步過濾(lv)、吸附(fu)處理后(hou)(hou),出水(shui)(shui)(shui)SS小于5 mg/L。
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2.4對色(se)度的去除效果
常規(gui)物(wu)化(hua)(hua)(hua)(hua)+生化(hua)(hua)(hua)(hua)組合和植物(wu)穩(wen)(wen)定(ding)塘(tang)(tang)(tang)-人(ren)(ren)工濕地系(xi)(xi)(xi)統(tong)(tong)區段進(jin)(jin)出(chu)水(shui)(shui)(shui)色(se)(se)(se)(se)(se)度(du)(du)(du)及色(se)(se)(se)(se)(se)度(du)(du)(du)去除(chu)(chu)效果如圖4所示(shi),系(xi)(xi)(xi)統(tong)(tong)總(zong)進(jin)(jin)水(shui)(shui)(shui)色(se)(se)(se)(se)(se)度(du)(du)(du)為(wei)(wei)650~1 200倍(bei)(bei)(bei),平(ping)均(jun)877倍(bei)(bei)(bei)。跟(gen)SS一樣,前40天(tian)(tian)色(se)(se)(se)(se)(se)度(du)(du)(du)波(bo)動(dong)較(jiao)小,在650~900倍(bei)(bei)(bei)之間,平(ping)均(jun)807倍(bei)(bei)(bei);第40天(tian)(tian)后(hou),進(jin)(jin)水(shui)(shui)(shui)色(se)(se)(se)(se)(se)度(du)(du)(du)范圍為(wei)(wei)800~1200倍(bei)(bei)(bei),波(bo)動(dong)較(jiao)大(da),極差達400倍(bei)(bei)(bei),是(shi)最低(di)值(zhi)(zhi)的(de)(de)1/2,進(jin)(jin)水(shui)(shui)(shui)平(ping)均(jun)值(zhi)(zhi)1 033倍(bei)(bei)(bei)。經(jing)物(wu)化(hua)(hua)(hua)(hua)+生化(hua)(hua)(hua)(hua)組合前40天(tian)(tian)出(chu)水(shui)(shui)(shui)色(se)(se)(se)(se)(se)度(du)(du)(du)平(ping)均(jun)120倍(bei)(bei)(bei),后(hou)20天(tian)(tian)平(ping)均(jun)130倍(bei)(bei)(bei),出(chu)水(shui)(shui)(shui)色(se)(se)(se)(se)(se)度(du)(du)(du)平(ping)均(jun)為(wei)(wei)123倍(bei)(bei)(bei),平(ping)均(jun)去除(chu)(chu)率約(yue)86.0%;經(jing)植物(wu)穩(wen)(wen)定(ding)塘(tang)(tang)(tang)-人(ren)(ren)工濕地系(xi)(xi)(xi)統(tong)(tong)深(shen)度(du)(du)(du)處理后(hou),出(chu)水(shui)(shui)(shui)波(bo)動(dong)較(jiao)少,出(chu)水(shui)(shui)(shui)平(ping)均(jun)值(zhi)(zhi)為(wei)(wei)50倍(bei)(bei)(bei)左(zuo)右,去除(chu)(chu)率為(wei)(wei)55.6%;整個(ge)系(xi)(xi)(xi)統(tong)(tong)工藝(yi)平(ping)均(jun)總(zong)去除(chu)(chu)率達93.8%。植物(wu)穩(wen)(wen)定(ding)塘(tang)(tang)(tang)-人(ren)(ren)工濕地系(xi)(xi)(xi)統(tong)(tong)對色(se)(se)(se)(se)(se)度(du)(du)(du)深(shen)度(du)(du)(du)去除(chu)(chu)效果明(ming)顯(xian),色(se)(se)(se)(se)(se)度(du)(du)(du)值(zhi)(zhi)降(jiang)低(di)了一半以上。由于印(yin)染廢水(shui)(shui)(shui)中(zhong)含(han)有(you)難生化(hua)(hua)(hua)(hua)降(jiang)解(jie)的(de)(de)PVC、化(hua)(hua)(hua)(hua)學助劑等,常規(gui)物(wu)化(hua)(hua)(hua)(hua)+生化(hua)(hua)(hua)(hua)組合不能(neng)將其(qi)中(zhong)復雜分子(zi)結構(gou)的(de)(de)顯(xian)色(se)(se)(se)(se)(se)集團徹底破壞(huai),導致出(chu)水(shui)(shui)(shui)色(se)(se)(se)(se)(se)度(du)(du)(du)值(zhi)(zhi)較(jiao)高。增加了植物(wu)穩(wen)(wen)定(ding)塘(tang)(tang)(tang)-人(ren)(ren)工濕地系(xi)(xi)(xi)統(tong)(tong)后(hou),易被吸附(fu)降(jiang)解(jie)的(de)(de)色(se)(se)(se)(se)(se)度(du)(du)(du)得(de)到去除(chu)(chu),但殘(can)余(yu)物(wu)質的(de)(de)顯(xian)色(se)(se)(se)(se)(se)使(shi)得(de)出(chu)水(shui)(shui)(shui)色(se)(se)(se)(se)(se)度(du)(du)(du)時有(you)略超過(guo)50倍(bei)(bei)(bei),只(zhi)達到基(ji)本排放標準,故此(ci)工藝(yi)仍有(you)改(gai)進(jin)(jin)的(de)(de)空間。
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2.5對(dui)氮(dan)磷等的去除效(xiao)果
系(xi)統(tong)(tong)(tong)工藝(yi)對(dui)COD、SS和色(se)度(du)等(deng)(deng)主要指標(biao)的去(qu)除(chu)作(zuo)用明(ming)顯外,對(dui)容易引(yin)起水(shui)(shui)體富營(ying)養化的氮磷等(deng)(deng)具有(you)很強的降解去(qu)除(chu)效果。系(xi)統(tong)(tong)(tong)進(jin)水(shui)(shui)NH3-N為1~7mg/L,平(ping)均4 mg/L;而平(ping)均出(chu)(chu)水(shui)(shui)僅0.1~1 mg/L,平(ping)均0.2 mg/L以下,去(qu)除(chu)率達(da)95.0%以上(shang)。進(jin)水(shui)(shui)TP9~30 mg/L,平(ping)均10 mg/L;而出(chu)(chu)水(shui)(shui)TP 0.1~0.8mg/L,平(ping)均約0.4 mg/L,去(qu)除(chu)率達(da)95.5%以上(shang)。對(dui)其他指標(biao)如pH、水(shui)(shui)溫等(deng)(deng),本(ben)系(xi)統(tong)(tong)(tong)工藝(yi)也具有(you)較強的調(diao)節能力(li)。系(xi)統(tong)(tong)(tong)進(jin)水(shui)(shui)pH達(da)11~13,呈(cheng)強堿性(xing),但(dan)經處(chu)理(li)(li)(li)后出(chu)(chu)水(shui)(shui)pH 7.3~8.2,跟自(zi)然水(shui)(shui)體pH基(ji)本(ben)一致(zhi),表明(ming)本(ben)系(xi)統(tong)(tong)(tong)對(dui)pH的處(chu)理(li)(li)(li)有(you)很強的適應(ying)和調(diao)節能力(li)。盡(jin)管(guan)常規物(wu)化+生化階段出(chu)(chu)水(shui)(shui)水(shui)(shui)溫較高(gao),達(da)30~40℃,但(dan)通(tong)入7 km外的植物(wu)穩定塘-人工濕(shi)地(di)系(xi)統(tong)(tong)(tong)自(zi)然冷卻后,出(chu)(chu)水(shui)(shui)基(ji)本(ben)與周圍(wei)河(he)涌水(shui)(shui)溫一致(zhi),不會(hui)產生熱污(wu)染。系(xi)統(tong)(tong)(tong)工藝(yi)每日產生的污(wu)泥(ni)量在200t左右(you),部分污(wu)泥(ni)被送至制磚廠綜合(he)利(li)用,剩余部分被運至發(fa)電(dian)廠焚燒處(chu)理(li)(li)(li)。
2.6經濟指標分(fen)析
該工(gong)(gong)程日處(chu)理量4×104m3,總(zong)投資為15 000萬元人(ren)民幣,包括建(jian)設(she)用(yong)地、植(zhi)物穩(wen)定塘(tang)、人(ren)工(gong)(gong)濕(shi)(shi)地建(jian)造費用(yong)、土(tu)建(jian)設(she)備、設(she)計(ji)安裝調試(shi)運(yun)行(xing)以及生(sheng)活辦公區的基礎建(jian)設(she)等(deng)。其(qi)中植(zhi)物穩(wen)定塘(tang)-人(ren)工(gong)(gong)濕(shi)(shi)地系統總(zong)投資約(yue)4 000萬人(ren)民幣。
運(yun)(yun)行費(fei)(fei)用(yong)主(zhu)要包括電費(fei)(fei):運(yun)(yun)行功率1 700 kW,電價以0.6元(yuan)/(kW·h)計(ji),處(chu)理(li)(li)廢水運(yun)(yun)行電費(fei)(fei)0.61元(yuan)/m3;藥劑費(fei)(fei):硫(liu)酸(suan)、硫(liu)酸(suan)亞鐵、石灰乳、PAM絮凝劑等,共約(yue)0.5元(yuan)/m3;人(ren)工費(fei)(fei):0.05元(yuan)/m3;植物穩定(ding)塘(tang)-人(ren)工濕地(農村郊區):54 400 m2,約(yue)82畝,如日(ri)處(chu)理(li)(li)量為(wei)4×104m3/d,每月管理(li)(li)運(yun)(yun)行費(fei)(fei)用(yong)需4 000元(yuan),年(nian)僅48 000元(yuan)。
3·結論
(1)本系統(tong)工(gong)藝適合處理(li)進水(shui)(shui)量(liang)大、COD負荷(he)高(gao)、成(cheng)分復(fu)雜等特點的(de)(de)綜合印染(ran)(ran)廢水(shui)(shui),可有(you)(you)效去(qu)除(chu)COD、SS和色度等污染(ran)(ran)物。按日(ri)處理(li)量(liang)4×104 m3、COD去(qu)除(chu)率(lv)96%估算,此系統(tong)工(gong)藝一年可削(xue)減COD排放約28.6萬t,對周邊河道水(shui)(shui)質環(huan)境(jing)改善(shan)有(you)(you)明顯的(de)(de)改善(shan)作用。對BOD5、SS和色度去(qu)除(chu)率(lv)可分別達98.4%、98.6%和92.8%以上,出水(shui)(shui)水(shui)(shui)質指標(biao)(biao)穩定達到(dao)GB8978-1996一級標(biao)(biao)準。
(2)印(yin)染污(wu)水(shui)處(chu)理(li)廠(chang)不僅完成了(le)工(gong)業(ye)園區要求的污(wu)水(shui)統一處(chu)理(li)目(mu)標,還創新性地(di)(di)(di)將人(ren)(ren)工(gong)濕地(di)(di)(di)大規模引(yin)入印(yin)染廢水(shui)的深度處(chu)理(li)。該植物穩定塘(tang)(tang)-人(ren)(ren)工(gong)濕地(di)(di)(di)系統深度處(chu)理(li)效(xiao)果良好,驗證了(le)植物穩定塘(tang)(tang)-人(ren)(ren)工(gong)濕地(di)(di)(di)系統處(chu)理(li)印(yin)染工(gong)業(ye)廢水(shui)的可(ke)行性。
(3)本(ben)工(gong)藝(yi)仍有繼續改進(jin)的(de)空間。植(zhi)物(wu)穩(wen)(wen)定(ding)塘(tang)-人(ren)工(gong)濕(shi)(shi)地系統(tong)深度(du)(du)降解(jie)印染(ran)廢(fei)水效果(guo)(guo)明顯、成本(ben)低廉,但對難生化(hua)降解(jie)的(de)印染(ran)污染(ran)物(wu)色度(du)(du)降解(jie)效果(guo)(guo)微(wei)弱。可考慮進(jin)入植(zhi)物(wu)穩(wen)(wen)定(ding)塘(tang)-人(ren)工(gong)濕(shi)(shi)地前(qian),增加一個二氧化(hua)氯或(huo)臭氧等高級氧化(hua)脫色工(gong)藝(yi),再(zai)經植(zhi)物(wu)穩(wen)(wen)定(ding)塘(tang)-人(ren)工(gong)濕(shi)(shi)地處理后出水水質會有更大的(de)提升。
參考文獻:略

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