養(yang)殖(zhi)廢(fei)水(shui)(shui)(shui)主要來源于(yu)養(yang)殖(zhi)畜禽(qin)尿液(ye),殘余糞(fen)便(bian),飼料殘渣以(yi)及(ji)沖洗水(shui)(shui)(shui)和部分生活污水(shui)(shui)(shui)。養(yang)殖(zhi)廢(fei)水(shui)(shui)(shui)水(shui)(shui)(shui)質(zhi)(zhi)水(shui)(shui)(shui)量變化大(da),懸(xuan)浮物(wu)(wu)(wu)多,有(you)機物(wu)(wu)(wu)濃度高(gao),氨氮含量高(gao),含有(you)重金屬和致病菌并伴有(you)惡(e)臭。養(yang)殖(zhi)廢(fei)水(shui)(shui)(shui)中(zhong)(zhong)的(de)污染物(wu)(wu)(wu)主要以(yi)固(gu)態,溶解態的(de)有(you)機物(wu)(wu)(wu)形式存在,使廢(fei)水(shui)(shui)(shui)BOD,COD,SS和色度等含量很(hen)高(gao),污染物(wu)(wu)(wu)可生物(wu)(wu)(wu)降解性好,此外廢(fei)水(shui)(shui)(shui)中(zhong)(zhong)含有(you)N,P等營(ying)養(yang)物(wu)(wu)(wu)質(zhi)(zhi),廢(fei)水(shui)(shui)(shui)中(zhong)(zhong)的(de)固(gu)體殘渣主要是有(you)機物(wu)(wu)(wu)質(zhi)(zhi)。因(yin)此,養(yang)殖(zhi)廢(fei)水(shui)(shui)(shui)先采用物(wu)(wu)(wu)理(li)(li)預處(chu)(chu)理(li)(li)進(jin)(jin)行固(gu)液(ye)分離,然后(hou)經厭氧處(chu)(chu)理(li)(li)將大(da)分子(zi)有(you)機物(wu)(wu)(wu)質(zhi)(zhi)分解成小分子(zi)物(wu)(wu)(wu)質(zhi)(zhi),再經過好氧處(chu)(chu)理(li)(li)進(jin)(jin)一步(bu)去除有(you)機污染物(wu)(wu)(wu),最后(hou)經消毒(du)出水(shui)(shui)(shui)達(da)標排放。
養殖(zhi)廢水處理工藝流程(cheng)
1.模式Ⅰ工藝
以能(neng)源(yuan)利(li)用(yong)(yong)(yong)與綜合利(li)用(yong)(yong)(yong)為主要目的,適(shi)用(yong)(yong)(yong)于(yu)當地(di)有較大(da)的能(neng)源(yuan)需求,沼氣能(neng)完全利(li)用(yong)(yong)(yong),同時周邊有足(zu)夠(gou)土(tu)地(di)消納(na)沼液(ye)、沼渣,并有一倍以上的土(tu)地(di)輪(lun)作面積,使整個養殖區域的畜(chu)禽(qin)排泄物在(zai)小區域范圍(wei)內全部達到循環利(li)用(yong)(yong)(yong)的情況
2.模式Ⅱ工藝
適用(yong)于能源需求不大(da),主要以進行(xing)污染物(wu)無害化處(chu)理(li)、降低有(you)機物(wu)濃度、減少沼液(ye)和沼渣(zha)消納(na)所需配(pei)套的土(tu)地(di)面(mian)積為(wei)目(mu)的,且(qie)養殖(zhi)場周圍(wei)具有(you)足夠土(tu)地(di)面(mian)積全部消納(na)低濃度沼液(ye),并且(qie)有(you)一定的土(tu)地(di)輪作面(mian)積的情況。
3.模式Ⅲ工藝
能源(yuan)需(xu)求不高且沼(zhao)液和沼(zhao)渣無(wu)法進行土地消納,廢水必須經處(chu)理后達標(biao)排放(fang)或(huo)回用。