隨著城鎮化進程的(de)(de)推進,農(nong)(nong)村(cun)污(wu)(wu)(wu)水(shui)處理(li)(li)是新(xin)農(nong)(nong)村(cun)建設的(de)(de)重要組(zu)成部分(fen)(fen)。農(nong)(nong)村(cun)生(sheng)活(huo)(huo)污(wu)(wu)(wu)水(shui)是面污(wu)(wu)(wu)染來源之一,全(quan)國(guo)90%以(yi)上的(de)(de)生(sheng)活(huo)(huo)污(wu)(wu)(wu)水(shui)或(huo)糞便廢水(shui)直接(jie)排(pai)放(fang)(fang)到地(di)(di)下或(huo)湖(hu)(hu)泊等(deng)流(liu)域,如太湖(hu)(hu)、滇池的(de)(de)富(fu)營養(yang)化均有部分(fen)(fen)來自于(yu)農(nong)(nong)村(cun)生(sheng)活(huo)(huo)污(wu)(wu)(wu)水(shui)。農(nong)(nong)村(cun)污(wu)(wu)(wu)水(shui)的(de)(de)隨意排(pai)放(fang)(fang),旱廁的(de)(de)使用(yong),造(zao)成江(jiang)河湖(hu)(hu)泊流(liu)域、地(di)(di)下水(shui)等(deng)水(shui)環境受到污(wu)(wu)(wu)染,治理(li)(li)農(nong)(nong)村(cun)污(wu)(wu)(wu)水(shui),不(bu)僅(jin)能改善農(nong)(nong)村(cun)生(sheng)活(huo)(huo)環境,還(huan)能控制流(liu)域的(de)(de)水(shui)質污(wu)(wu)(wu)染和湖(hu)(hu)泊的(de)(de)富(fu)營養(yang)化,改善水(shui)體(ti)環境,同時處理(li)(li)的(de)(de)中(zhong)水(shui)用(yong)于(yu)農(nong)(nong)業(ye)灌溉,緩解農(nong)(nong)業(ye)用(yong)水(shui)的(de)(de)緊張(zhang)。因(yin)此急需研究新(xin)農(nong)(nong)村(cun)的(de)(de)污(wu)(wu)(wu)水(shui) 系統,提出適合我(wo)國(guo)的(de)(de)多樣化農(nong)(nong)村(cun)污(wu)(wu)(wu)水(shui)處理(li)(li)系統。
1 農村污水處理現狀(zhuang)
1. 1 國(guo)外農村污水處理現狀
農(nong)(nong)(nong)村(cun)污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)處(chu)(chu)理(li)(li)(li)(li)方面(mian),各國都有自(zi)己的(de)(de)(de)處(chu)(chu)理(li)(li)(li)(li)工(gong)藝。日本在1977年(nian),實行農(nong)(nong)(nong)村(cun)污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)處(chu)(chu)理(li)(li)(li)(li)計(ji)劃,成(cheng)立農(nong)(nong)(nong)村(cun)污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)處(chu)(chu)理(li)(li)(li)(li)協會(hui),負責研究適合農(nong)(nong)(nong)村(cun)污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)處(chu)(chu)理(li)(li)(li)(li)方案。其設(she)計(ji)了(le)JARUS 模式(shi)的(de)(de)(de)15種污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)處(chu)(chu)理(li)(li)(li)(li)裝置,處(chu)(chu)理(li)(li)(li)(li)工(gong)藝主要是生(sheng)物(wu)膜法和(he)浮游生(sheng)物(wu)法,具有體積(ji)小(xiao)、成(cheng)本低、操作簡單的(de)(de)(de)特(te)點(dian)。到(dao)1996年(nian)底,建成(cheng)2000座農(nong)(nong)(nong)村(cun)小(xiao)型污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)廠,處(chu)(chu)理(li)(li)(li)(li)后的(de)(de)(de)中(zhong)(zhong)水(shui)(shui)(shui)(shui)用(yong)(yong)于農(nong)(nong)(nong)業(ye)灌溉,污(wu)(wu)(wu)(wu)泥用(yong)(yong)作農(nong)(nong)(nong)田肥料。德(de)(de)國也很重視污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)處(chu)(chu)理(li)(li)(li)(li),到(dao)1992年(nian),全德(de)(de)國的(de)(de)(de)污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)接管率就達到(dao)92.2%。在相(xiang)對集中(zhong)(zhong)的(de)(de)(de)農(nong)(nong)(nong)村(cun)采用(yong)(yong)集中(zhong)(zhong)處(chu)(chu)理(li)(li)(li)(li),對于分(fen)散(san)的(de)(de)(de)農(nong)(nong)(nong)村(cun)采用(yong)(yong)分(fen)散(san)小(xiao)型污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)處(chu)(chu)理(li)(li)(li)(li)設(she)施,其主要以腐化池為主,外(wai)加(jia)生(sheng)物(wu)濾池、生(sheng)物(wu)接觸池、穩定塘(tang)等。韓(han)國農(nong)(nong)(nong)村(cun)居民(min)多(duo)分(fen)散(san)居住,采用(yong)(yong)小(xiao)型、簡易的(de)(de)(de)污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)處(chu)(chu)理(li)(li)(li)(li)系統,工(gong)藝為濕地污(wu)(wu)(wu)(wu)水(shui)(shui)(shui)(shui)處(chu)(chu)理(li)(li)(li)(li)系統,其缺點(dian)是占(zhan)地大,受充分(fen)供氧、氣(qi)溫和(he)植物(wu)生(sheng)長季節的(de)(de)(de)影響等。
1. 2 國內農村污水(shui)處理現狀
我(wo)國農(nong)村(cun)污水處(chu)理(li)設(she)施(shi)建(jian)設(she)比較晚,“十(shi)一五”規劃推(tui)動農(nong)村(cun)污水處(chu)理(li)建(jian)設(she),要(yao)求(qiu)農(nong)村(cun)無(wu)公(gong)害排放,但是我(wo)國農(nong)村(cun)經濟(ji)發展落后(hou),農(nong)村(cun)污水處(chu)理(li)設(she)施(shi)建(jian)設(she)才剛起步。
北方部(bu)(bu)分(fen)農村(cun)(cun)(cun)及沿海地區(qu)大部(bu)(bu)分(fen)農村(cun)(cun)(cun)配有(you)污(wu)水處(chu)理(li)(li)(li)系(xi)(xi)統,多(duo)以(yi)單(dan)村(cun)(cun)(cun)處(chu)理(li)(li)(li)為主。如北京各(ge)村(cun)(cun)(cun)現(xian)在實行(xing)污(wu)水處(chu)理(li)(li)(li)建設,多(duo)采(cai)單(dan)村(cun)(cun)(cun)處(chu)理(li)(li)(li)模式,只(zhi)有(you)部(bu)(bu)分(fen)相對集中的(de)(de)村(cun)(cun)(cun)落(luo)采(cai)用集中處(chu)理(li)(li)(li);還有(you)少(shao)數(shu)(shu)靠(kao)近城(cheng)(cheng)鎮的(de)(de)村(cun)(cun)(cun)落(luo),污(wu)水管(guan)(guan)接入城(cheng)(cheng)市(shi)集中處(chu)理(li)(li)(li)管(guan)(guan)網。分(fen)散(san)布(bu)置模式采(cai)用的(de)(de)處(chu)理(li)(li)(li)工藝(yi)主要有(you)人工濕地、生物(wu)膜法(fa)(MBR) 、智(zhi)能化小型污(wu)水處(chu)理(li)(li)(li)工藝(yi)等。但存(cun)在部(bu)(bu)分(fen)系(xi)(xi)統冬(dong)季低溫無法(fa)運行(xing);日變(bian)化系(xi)(xi)數(shu)(shu)大,系(xi)(xi)統少(shao)數(shu)(shu)時(shi)間高負荷運行(xing);污(wu)水量太小時(shi),停(ting)止運行(xing)。沿海地區(qu)等集中村(cun)(cun)(cun)落(luo)設有(you)污(wu)水處(chu)理(li)(li)(li)系(xi)(xi)統,但處(chu)理(li)(li)(li)工藝(yi)落(luo)后(hou),多(duo)采(cai)用城(cheng)(cheng)市(shi)污(wu)水處(chu)理(li)(li)(li)工藝(yi);靠(kao)近城(cheng)(cheng)市(shi)村(cun)(cun)(cun)落(luo),接入城(cheng)(cheng)市(shi)管(guan)(guan)網;分(fen)散(san)的(de)(de)、經濟相對差的(de)(de)村(cun)(cun)(cun)落(luo)無污(wu)水處(chu)理(li)(li)(li)設施。
2 污水(shui)處理(li)工(gong)藝
2. 1 穩定塘處理工藝(yi)
穩定(ding)塘(tang)是(shi)由若(ruo)干自然(ran)或人(ren)工(gong)開挖(wa)的池塘(tang)組成,通過塘(tang)內的藻、菌、浮游水(shui)(shui)生物(wu)的綜(zong)合作用達(da)到凈化(hua)污(wu)水(shui)(shui),其(qi)出水(shui)(shui)水(shui)(shui)質較好。研究浮萍穩定(ding)塘(tang)系統(tong)處理村鎮或社區污(wu)水(shui)(shui)中(zhong),發現TSS 去除率(lv)可達(da)80% ,COD去除率(lv)大于75% ,但(dan)氣溫下降,COD去除率(lv)降到60%。
在傳統基礎上改進的高效藻類穩定塘比傳統的穩定塘有更多的生物,并增加攪拌裝置,促進污水混合;調節塘內的氧氣和二氧化碳的濃度,及水溫和水質,從而提高有機物、氮和磷的去除率。高效藻類穩定塘受光照、溫度、水深和塘內流速的影響大。
2. 2 人工濕(shi)地處(chu)理(li)工藝
人(ren)工濕地處理系統(tong)是在人(ren)工鋪(pu)的(de)(de)基質上種植(zhi)蘆葦、大麻、香蒲、鳳眼蓮(lian)等水生植(zhi)物(wu)(wu),利用濕地構成的(de)(de)土壤(rang)、植(zhi)物(wu)(wu),水生動物(wu)(wu)和(he)微(wei)生物(wu)(wu)共(gong)同過濾、吸收污染物(wu)(wu)的(de)(de)工藝。按植(zhi)物(wu)(wu)類型有(you)挺水植(zhi)物(wu)(wu)和(he)浮游植(zhi)物(wu)(wu),按照(zhao)水流形式分為表(biao)面流濕地、替流人(ren)工濕地和(he)垂直(zhi)流人(ren)工濕地。
濕地的(de)(de)基質、植(zhi)物和水中微生(sheng)物是凈(jing)化(hua)污(wu)水的(de)(de)主體,植(zhi)物起消耗營(ying)養物質和輸氧的(de)(de)功能。植(zhi)物的(de)(de)人工濕地的(de)(de)硝化(hua)能力明顯高于無植(zhi)物的(de)(de)人工濕地。
2. 3 土地處理工藝
在人工(gong)控制下,污水經(jing)過土(tu)壤- 植物(wu)(wu)系(xi)統(tong)(tong)的(de)(de)(de)物(wu)(wu)理(li)(li)(li)、化學、生物(wu)(wu)等(deng)的(de)(de)(de)處(chu)理(li)(li)(li),達到凈化的(de)(de)(de)效果(guo),是(shi)(shi)無動力處(chu)理(li)(li)(li)工(gong)藝(yi)(yi)。我國(guo)現有的(de)(de)(de)工(gong)藝(yi)(yi)有快速滲(shen)濾處(chu)理(li)(li)(li)系(xi)統(tong)(tong)、地下滲(shen)濾處(chu)理(li)(li)(li)系(xi)統(tong)(tong)等(deng)。快速滲(shen)濾處(chu)理(li)(li)(li)系(xi)統(tong)(tong)是(shi)(shi)使滲(shen)透性好的(de)(de)(de)土(tu)壤處(chu)于周期性的(de)(de)(de)淹沒和干旱的(de)(de)(de)交替(ti)狀態,使污水經(jing)歷厭氧和好氧處(chu)理(li)(li)(li)的(de)(de)(de)一種處(chu)理(li)(li)(li)工(gong)藝(yi)(yi)。具有較好的(de)(de)(de)氮、磷(lin)去除率。
2. 4 生物膜處理工藝
生(sheng)(sheng)物膜(mo)法(fa)是指以天(tian)然材料 、合成(cheng)材料(如(ru)纖維) 為載體(ti),其表面(mian)的(de)生(sheng)(sheng)物膜(mo)為微生(sheng)(sheng)物提(ti)供附著面(mian),微生(sheng)(sheng)物通過分泌的(de)酵素和催(cui)化(hua)(hua)劑降解污水中(zhong)的(de)物質,同時代謝生(sheng)(sheng)成(cheng)物排出生(sheng)(sheng)物膜(mo)。生(sheng)(sheng)物膜(mo)法(fa)主要工(gong)藝有(you)生(sheng)(sheng)物廊道、生(sheng)(sheng)物濾池、生(sheng)(sheng)物接觸氧化(hua)(hua)池等。生(sheng)(sheng)物膜(mo)法(fa)具(ju)有(you)較高的(de)處理效率,對于(yu)受有(you)機物及氨氮輕度(du)污染水體(ti)有(you)明顯的(de)凈化(hua)(hua)效果。現有(you)簡易、方便操作、集一體(ti)的(de)生(sheng)(sheng)物膜(mo)工(gong)藝如(ru)膜(mo)生(sheng)(sheng)物反應(ying)器(MBR) 和智(zhi)能化(hua)(hua)小型生(sheng)(sheng)活(huo)污水反應(ying)器。
目前農(nong)村(cun)生(sheng)活污(wu)(wu)水(shui)(shui)(shui)任意排放,造成流域等(deng)水(shui)(shui)(shui)體(ti)污(wu)(wu)染,同時農(nong)村(cun)經(jing)濟發展趕不(bu)上城鎮,地(di)區特點突出(chu)等(deng),因此新農(nong)村(cun)污(wu)(wu)水(shui)(shui)(shui)處(chu)(chu)理系(xi)統建設迫(po)切(qie)需要經(jing)濟、高效(xiao)、自動化高的(de)(de)(de)一(yi)(yi)體(ti)化處(chu)(chu)理系(xi)統,以(yi)適應我國農(nong)村(cun)污(wu)(wu)水(shui)(shui)(shui)的(de)(de)(de)多樣性(xing)等(deng)。在選擇工(gong)藝時,要結合(he)當地(di)實(shi)際情況(kuang),如(ru)水(shui)(shui)(shui)質(zhi)、水(shui)(shui)(shui)溫、經(jing)濟發展水(shui)(shui)(shui)平等(deng)因素(su),綜(zong)合(he)考慮確定具體(ti)工(gong)藝。針(zhen)對我國農(nong)村(cun)污(wu)(wu)水(shui)(shui)(shui)處(chu)(chu)理的(de)(de)(de)現狀，污(wu)(wu)水(shui)(shui)(shui)寶(bao)特推出(chu)四種型號的(de)(de)(de)一(yi)(yi)體(ti)化生(sheng)活污(wu)(wu)水(shui)(shui)(shui)處(chu)(chu)理設備解決農(nong)村(cun)生(sheng)活污(wu)(wu)水(shui)(shui)(shui)處(chu)(chu)理難、占地(di)面積(ji)大(da)、運行(xing)維護(hu)困難的(de)(de)(de)難題。并且經(jing)大(da)量實(shi)踐證(zheng)明，經(jing)處(chu)(chu)理后的(de)(de)(de)污(wu)(wu)水(shui)(shui)(shui)完全(quan)符合(he)城鎮污(wu)(wu)水(shui)(shui)(shui)處(chu)(chu)理廠污(wu)(wu)染物排放標準要求(qiu)。