節(jie)能(neng)(neng)減(jian)排是(shi)整(zheng)個國家(jia)的戰略目標，鋼(gang)鐵(tie)工(gong)(gong)(gong)(gong)(gong)業(ye)作(zuo)為重(zhong)點能(neng)(neng)耗(hao)行業(ye)之(zhi)一，是(shi)節(jie)能(neng)(neng)減(jian)排的重(zhong)點。節(jie)約工(gong)(gong)(gong)(gong)(gong)業(ye)新(xin)水(shui)(shui)(shui)(shui)(shui)用(yong)量(liang)，減(jian)少(shao)工(gong)(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)的排放量(liang)，是(shi)鋼(gang)鐵(tie)企(qi)業(ye)水(shui)(shui)(shui)(shui)(shui)系(xi)統(tong)(tong)所追求的目標。鋼(gang)鐵(tie)企(qi)業(ye)水(shui)(shui)(shui)(shui)(shui)系(xi)統(tong)(tong)現普遍采(cai)用(yong)循環—串級供水(shui)(shui)(shui)(shui)(shui)體制(zhi)、限制(zhi)工(gong)(gong)(gong)(gong)(gong)業(ye)新(xin)水(shui)(shui)(shui)(shui)(shui)的直流(liu)用(yong)水(shui)(shui)(shui)(shui)(shui)。將工(gong)(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)收集后處(chu)理(li)制(zhi)成回(hui)用(yong)水(shui)(shui)(shui)(shui)(shui)、工(gong)(gong)(gong)(gong)(gong)業(ye)新(xin)水(shui)(shui)(shui)(shui)(shui)、脫鹽水(shui)(shui)(shui)(shui)(shui)、軟化水(shui)(shui)(shui)(shui)(shui)或純水(shui)(shui)(shui)(shui)(shui)等用(yong)于生產，是(shi)目前鋼(gang)鐵(tie)企(qi)業(ye)回(hui)用(yong)工(gong)(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)、實(shi)現污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)資(zi)源(yuan)化的常見方(fang)式(shi)。但在(zai)詳細(xi)實(shi)施(shi)(shi)工(gong)(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)處(chu)理(li)和(he)回(hui)用(yong)時(shi)，很多企(qi)業(ye)卻面(mian)臨著工(gong)(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)量(liang)遠(yuan)大(da)于回(hui)用(yong)水(shui)(shui)(shui)(shui)(shui)量(liang)，處(chu)理(li)后的工(gong)(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)因缺少(shao)用(yong)戶(hu)只能(neng)(neng)外排而同(tong)(tong)時(shi)還需引入大(da)量(liang)的工(gong)(gong)(gong)(gong)(gong)業(ye)新(xin)水(shui)(shui)(shui)(shui)(shui)的尷尬局(ju)面(mian)。要(yao)(yao)實(shi)現節(jie)能(neng)(neng)減(jian)排不(bu)僅要(yao)(yao)研究水(shui)(shui)(shui)(shui)(shui)處(chu)理(li)工(gong)(gong)(gong)(gong)(gong)藝，更(geng)重(zhong)要(yao)(yao)的是(shi)要(yao)(yao)實(shi)現工(gong)(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)排放量(liang)和(he)回(hui)用(yong)水(shui)(shui)(shui)(shui)(shui)量(liang)之(zhi)間的平衡。作(zuo)者針對在(zai)不(bu)同(tong)(tong)的生產工(gong)(gong)(gong)(gong)(gong)藝(長(chang)流(liu)程和(he)短流(liu)程)中(zhong)，工(gong)(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)的回(hui)用(yong)方(fang)式(shi)和(he)回(hui)用(yong)率(lv)的不(bu)同(tong)(tong)，分析了(le)工(gong)(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)的回(hui)用(yong)方(fang)式(shi)、并探討了(le)提高回(hui)用(yong)率(lv)的技術措(cuo)施(shi)(shi)。

1 工業污水的主要來源及特點分(fen)析(xi)

鋼鐵企業(ye)(ye)(ye)工業(ye)(ye)(ye)污水(shui)主要(yao)(yao)來源于濁循環(huan)水(shui)系(xi)統的(de)(de)排污水(shui)(敞開(kai)式(shi)凈循環(huan)水(shui)系(xi)統的(de)(de)排污水(shui)一般作(zuo)為濁循環(huan)水(shui)系(xi)統的(de)(de)補充水(shui)，焦化(hua)、冷軋(ya)等(deng)特種工業(ye)(ye)(ye)污水(shui)通(tong)常單獨(du)處理)。工業(ye)(ye)(ye)污水(shui)中含(han)懸(xuan)浮物、雜質、油等(deng)，另外其含(han)鹽(yan)量(liang)較高(gao)，就濃(nong)縮倍數(shu)而言，通(tong)常可(ke)達(da)到工業(ye)(ye)(ye)新水(shui)的(de)(de)5～6倍以上(以Cl-含(han)量(liang)來計算水(shui)系(xi)統的(de)(de)濃(nong)縮倍數(shu)及含(han)鹽(yan)量(liang)的(de)(de)變化(hua))，這是工業(ye)(ye)(ye)污水(shui)重要(yao)(yao)的(de)(de)特點，也(ye)是影響其回用的(de)(de)重要(yao)(yao)因素。

2 工業污水目(mu)前(qian)常見(jian)回用方式

目前工業(ye)污(wu)水(shui)回(hui)用的常見方(fang)式為(wei)將工業(ye)污(wu)水(shui)收集后處理制成回(hui)用水(shui)、工業(ye)新(xin)水(shui)、脫鹽水(shui)、軟(ruan)化水(shui)或純水(shui)等用于生產。

2.1工業污水經過普通(tong)處理成回用水

工業污水(shui)(shui)經過常規水(shui)(shui)處(chu)理工藝(如混凝、沉淀、除油、過濾等)處(chu)理后制(zhi)成回用(yong)水(shui)(shui)，原工業污水(shui)(shui)中的懸浮(fu)物(wu)、雜質、油等均得到了(le)有(you)效的去除，但其(qi)含鹽量并沒有(you)降低，其(qi)含鹽量遠高于工業凈循環(huan)水(shui)(shui)和濁循環(huan)水(shui)(shui)。

2.2工業(ye)污水(shui)經脫(tuo)鹽(yan)制(zhi)成(cheng)脫(tuo)鹽(yan)水(shui)、軟化(hua)水(shui)及(ji)純水(shui)

脫(tuo)鹽(yan)(yan)(yan)(yan)(yan)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)、軟化水(shui)(shui)(shui)(shui)(shui)(shui)(shui)及純水(shui)(shui)(shui)(shui)(shui)(shui)(shui)，常用(yong)于(yu)鋼鐵(tie)企業煉鐵(tie)、煉鋼、連鑄等(deng)單元關鍵設備的間接冷(leng)卻密閉(bi)式循環水(shui)(shui)(shui)(shui)(shui)(shui)(shui)系(xi)統以及鍋爐(lu)、蓄(xu)熱器等(deng)的補充用(yong)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)。隨(sui)著全膜法(fa)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)處理系(xi)統造(zao)價和運行成(cheng)本的日益降低，超濾加二級(ji)反(fan)滲透(tou)工(gong)藝，已廣泛(fan)應用(yong)于(yu)鋼鐵(tie)企業脫(tuo)鹽(yan)(yan)(yan)(yan)(yan)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)的制(zhi)取。但在制(zhi)成(cheng)脫(tuo)鹽(yan)(yan)(yan)(yan)(yan)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)、軟化水(shui)(shui)(shui)(shui)(shui)(shui)(shui)及純水(shui)(shui)(shui)(shui)(shui)(shui)(shui)的同時，也將產生約占(zhan)脫(tuo)鹽(yan)(yan)(yan)(yan)(yan)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)、軟化水(shui)(shui)(shui)(shui)(shui)(shui)(shui)及純水(shui)(shui)(shui)(shui)(shui)(shui)(shui)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)量40～50%左右(you)的濃鹽(yan)(yan)(yan)(yan)(yan)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)，濃鹽(yan)(yan)(yan)(yan)(yan)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)的含鹽(yan)(yan)(yan)(yan)(yan)量將更高，按常規(gui)工(gong)業污水(shui)(shui)(shui)(shui)(shui)(shui)(shui)反(fan)滲透(tou)的回收(shou)率(lv)約為75%計算，濃鹽(yan)(yan)(yan)(yan)(yan)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)針(zhen)對(dui)工(gong)業污水(shui)(shui)(shui)(shui)(shui)(shui)(shui)的濃縮倍(bei)數(shu)將達到4倍(bei)以上，其含鹽(yan)(yan)(yan)(yan)(yan)量針(zhen)對(dui)工(gong)業新水(shui)(shui)(shui)(shui)(shui)(shui)(shui)而(er)言達到了20倍(bei)以上。

2.3工(gong)(gong)業污水全部經脫鹽(yan)制成工(gong)(gong)業新水

如果將全部工業(ye)(ye)污水(shui)脫鹽制成(cheng)工業(ye)(ye)新水(shui)，其生產成(cheng)本將大幅度(du)提高，在短期內缺乏(fa)實施(shi)的(de)(de)可操作性，同(tong)時制成(cheng)工業(ye)(ye)新水(shui)的(de)(de)同(tong)時將產生更(geng)多的(de)(de)反滲透濃水(shui)。

3 鋼鐵企業主生(sheng)產工藝對各類水 的需求分析

3.1鋼鐵企業主(zhu)生產工藝分類

我國鋼鐵(tie)工(gong)業按其生(sheng)(sheng)(sheng)(sheng)產(chan)產(chan)品和生(sheng)(sheng)(sheng)(sheng)產(chan)工(gong)藝流(liu)(liu)(liu)(liu)程(cheng)可分為長流(liu)(liu)(liu)(liu)程(cheng)生(sheng)(sheng)(sheng)(sheng)產(chan)和短(duan)流(liu)(liu)(liu)(liu)程(cheng)生(sheng)(sheng)(sheng)(sheng)產(chan)兩類。長流(liu)(liu)(liu)(liu)程(cheng)的生(sheng)(sheng)(sheng)(sheng)產(chan)流(liu)(liu)(liu)(liu)程(cheng)主(zhu)要(yao)包括燒結(球團)、焦化、煉(lian)鐵(tie)、煉(lian)鋼、軋鋼等(deng)生(sheng)(sheng)(sheng)(sheng)產(chan)工(gong)序;短(duan)流(liu)(liu)(liu)(liu)程(cheng)的生(sheng)(sheng)(sheng)(sheng)產(chan)流(liu)(liu)(liu)(liu)程(cheng)主(zhu)要(yao)包括煉(lian)鋼、軋鋼等(deng)生(sheng)(sheng)(sheng)(sheng)產(chan)工(gong)序。長流(liu)(liu)(liu)(liu)程(cheng)的煉(lian)鋼工(gong)藝一(yi)般(ban)是轉爐(lu)，短(duan)流(liu)(liu)(liu)(liu)程(cheng)的煉(lian)鋼工(gong)藝一(yi)般(ban)是電爐(lu)。

3.2長(chang)流程生產工藝用水(shui)需(xu)求

煉(lian)鐵、煉(lian)鋼、連鑄(zhu)、冷(leng)軋等單元如爐體、氧(yang)槍、結晶器(qi)等關鍵設備的(de)間接冷(leng)卻密閉式循環(huan)水系統(tong)以及(ji)鍋爐、蓄熱(re)器(qi)等的(de)補(bu)充用水一般采用脫鹽水、軟化水及(ji)純水。

燒結、煉鐵、煉鋼、連(lian)鑄、熱軋(ya)、冷(leng)軋(ya)等單(dan)元一般設備的間接冷(leng)卻循環水(shui)(shui)系統補充水(shui)(shui)一般采用工(gong)業新(xin)水(shui)(shui)。各主工(gong)藝(yi)單(dan)元濁循環水(shui)(shui)系統由凈循環強制(zhi)排(pai)污水(shui)(shui)補水(shui)(shui)，水(shui)(shui)量不夠的采用工(gong)業新(xin)水(shui)(shui)。

燒(shao)結的(de)一次混(hun)(hun)合(he)(he)和二(er)次混(hun)(hun)合(he)(he)用(yong)水(shui)(shui)(shui)以及渣處理等直(zhi)流用(yong)戶或是(shi)澆灑地坪等一般采(cai)(cai)用(yong)回用(yong)水(shui)(shui)(shui)，反滲透系統的(de)濃水(shui)(shui)(shui)也可采(cai)(cai)用(yong)。燒(shao)結一次混(hun)(hun)合(he)(he)和二(er)次混(hun)(hun)合(he)(he)的(de)用(yong)水(shui)(shui)(shui)量(liang)(liang)一般為(wei)每小時十(shi)(shi)幾(ji)到幾(ji)十(shi)(shi)立方米;高爐爐渣粒化如(ru)(ru)采(cai)(cai)用(yong)沖渣方式(shi)，其(qi)噸渣耗(hao)水(shui)(shui)(shui)量(liang)(liang)約(yue)為(wei)8～12 m3，如(ru)(ru)采(cai)(cai)用(yong)泡渣方式(shi)，其(qi)噸渣耗(hao)水(shui)(shui)(shui)量(liang)(liang)約(yue)為(wei)1.0～1.5 m3;轉爐煉(lian)鋼渣量(liang)(liang)較大(da)，一般采(cai)(cai)用(yong)淺(qian)熱潑渣盤工(gong)藝(yi)，耗(hao)水(shui)(shui)(shui)量(liang)(liang)約(yue)為(wei)噸渣1.2 m3[1]。

從用(yong)水(shui)需求量來看，由于(yu)存在(zai)一次混合和二次混合用(yong)水(shui)以及渣處(chu)理等(deng)工藝(yi)用(yong)戶，回用(yong)水(shui)量較大，與工業新水(shui)用(yong)量接近，甚(shen)至大于(yu)工業新水(shui)用(yong)量，其次是脫鹽水(shui)、軟(ruan)化水(shui)及純水(shui)。

3.3短流程生產工藝用水需求

短流程工藝(yi)用水需(xu)求(qiu)(qiu)總的來說(shuo)與長流程類似(si)，但是沒(mei)有煉鐵(tie)、燒(shao)結單元，因此也(ye)沒(mei)有燒(shao)結的一(yi)次混合、二次混合和(he)煉鐵(tie)的爐(lu)渣(zha)粒化等回(hui)(hui)用水用戶，另外電爐(lu)爐(lu)渣(zha)處理也(ye)與轉爐(lu)爐(lu)渣(zha)處理工藝(yi)不同，回(hui)(hui)用水需(xu)求(qiu)(qiu)量(liang)遠(yuan)小于長流程生產工藝(yi)。

從用(yong)水需求(qiu)量來看，工業新水量是最大的(de)，其次是脫鹽水、軟化水及純水，而回(hui)用(yong)水用(yong)水量的(de)需求(qiu)更少。

4.工業污水回用(yong)方式(shi)探討

4.1長流程生產工藝污水回(hui)用

對(dui)于(yu)(yu)長流程生(sheng)產工(gong)藝的鋼鐵企業，鑒于(yu)(yu)回用(yong)(yong)水(shui)需求量較大，建議將部分工(gong)業污水(shui)制(zhi)成脫(tuo)鹽水(shui)、軟化水(shui)或(huo)純水(shui)用(yong)(yong)于(yu)(yu)生(sheng)產，將反滲(shen)透濃(nong)水(shui)和(he)其他由(you)工(gong)業污水(shui)制(zhi)成的回用(yong)(yong)水(shui)回用(yong)(yong)至燒結(jie)的一(yi)次混合(he)和(he)二次混合(he)用(yong)(yong)水(shui)以(yi)及(ji)渣處理(li)等直流用(yong)(yong)戶(hu)或(huo)是澆(jiao)灑地坪。

4.2短流程生(sheng)產工藝污水回用

對于短流程生產工藝的鋼鐵(tie)企(qi)業，工業污水(shui)(shui)排放量(liang)和(he)回(hui)(hui)用(yong)(yong)水(shui)(shui)量(liang)之間(jian)不平衡的矛盾比較突出。首(shou)先是(shi)回(hui)(hui)用(yong)(yong)水(shui)(shui)用(yong)(yong)戶少，回(hui)(hui)用(yong)(yong)水(shui)(shui)需求量(liang)也少;而工業污水(shui)(shui)經過常規(gui)處理制成(cheng)的回(hui)(hui)用(yong)(yong)水(shui)(shui)含鹽量(liang)高，無法(fa)用(yong)(yong)于循環水(shui)(shui)系統做補充水(shui)(shui)，回(hui)(hui)用(yong)(yong)水(shui)(shui)無法(fa)有效地消耗;另外，在制取脫鹽水(shui)(shui)、軟化(hua)水(shui)(shui)及純水(shui)(shui)過程中將產生含鹽量(liang)更高的反(fan)滲透濃水(shui)(shui)。

5.解決短流程(cheng)生產(chan)工藝(yi)水量平衡問題的探討(tao)

解決(jue)工業(ye)(ye)污水(shui)(shui)(shui)(shui)量與回用(yong)水(shui)(shui)(shui)(shui)量之(zhi)間不平衡的(de)方法有(you)兩種(zhong)：一(yi)是(shi)增加(jia)回用(yong)水(shui)(shui)(shui)(shui)用(yong)戶，二(er)是(shi)降低工業(ye)(ye)污水(shui)(shui)(shui)(shui)量。增加(jia)新的(de)回用(yong)水(shui)(shui)(shui)(shui)用(yong)戶受到鋼(gang)鐵企業(ye)(ye)主生產工藝的(de)嚴(yan)格限(xian)制(zhi)，較為難以實施，因此(ci)如何有(you)效地控制(zhi)工業(ye)(ye)污水(shui)(shui)(shui)(shui)的(de)排水(shui)(shui)(shui)(shui)量是(shi)研(yan)究(jiu)的(de)主要內容。而(er)要控制(zhi)工業(ye)(ye)污水(shui)(shui)(shui)(shui)量，就要從源頭抓起，從工業(ye)(ye)新水(shui)(shui)(shui)(shui)和循(xun)環(huan)水(shui)(shui)(shui)(shui)系(xi)統(tong)(敞開式凈循(xun)環(huan)水(shui)(shui)(shui)(shui)系(xi)統(tong)和濁循(xun)環(huan)水(shui)(shui)(shui)(shui)系(xi)統(tong))本(ben)身入手(shou)加(jia)以研(yan)究(jiu)。筆者將結合某(mou)鋼(gang)鐵企業(ye)(ye)的(de)工程(cheng)實例加(jia)以分析(xi)。如何提(ti)高短流程(cheng)生產工藝污水(shui)(shui)(shui)(shui)回用(yong)率是(shi)急須解決(jue)的(de)問(wen)題。

5.1某(mou)鋼鐵公(gong)司全廠給排(pai)水現狀及面(mian)臨的問題

某鋼(gang)鐵(tie)公司已有(you)工(gong)(gong)(gong)業(ye)新(xin)水(shui)(shui)處(chu)理(li)(li)站、污(wu)(wu)水(shui)(shui)處(chu)理(li)(li)站。全廠工(gong)(gong)(gong)業(ye)用(yong)新(xin)水(shui)(shui)取(qu)自運河(he)(he)地表水(shui)(shui)，經(jing)(jing)工(gong)(gong)(gong)業(ye)新(xin)水(shui)(shui)處(chu)理(li)(li)站處(chu)理(li)(li)后，供(gong)公司工(gong)(gong)(gong)業(ye)水(shui)(shui)總管網(wang)，作各工(gong)(gong)(gong)藝(yi)單元(yuan)(燒(shao)結(jie)、煉鐵(tie)、煉鋼(gang)、軋鋼(gang)、制氧(yang)等)的工(gong)(gong)(gong)業(ye)凈循環水(shui)(shui)系統補充水(shui)(shui)用(yong)。全公司污(wu)(wu)水(shui)(shui)集中回流至污(wu)(wu)水(shui)(shui)處(chu)理(li)(li)站，經(jing)(jing)處(chu)理(li)(li)后供(gong)各工(gong)(gong)(gong)藝(yi)單元(yuan)(主要(yao)是燒(shao)結(jie)的一次(ci)和二(er)次(ci)混合用(yong)水(shui)(shui)以及煉鋼(gang)熱潑渣用(yong)水(shui)(shui))及消(xiao)防水(shui)(shui)系統等，多余(yu)的處(chu)理(li)(li)后的污(wu)(wu)水(shui)(shui)排放至運河(he)(he)。

根據集團及(ji)公司的(de)總體(ti)規劃，公司將新(xin)(xin)建(jian)產品(pin)結構調整和配(pei)套工(gong)(gong)程(cheng)，工(gong)(gong)程(cheng)建(jian)設完成后，將提出新(xin)(xin)的(de)工(gong)(gong)業(ye)(ye)新(xin)(xin)水(shui)(shui)、回用水(shui)(shui)、純(chun)水(shui)(shui)用水(shui)(shui)以及(ji)工(gong)(gong)業(ye)(ye)污(wu)水(shui)(shui)排水(shui)(shui)的(de)要(yao)求(qiu)。原(yuan)有(you)的(de)工(gong)(gong)業(ye)(ye)新(xin)(xin)水(shui)(shui)處理站(zhan)(zhan)(zhan)、污(wu)水(shui)(shui)處理站(zhan)(zhan)(zhan)已經滿負荷(he)運轉，必須建(jian)設新(xin)(xin)的(de)水(shui)(shui)處理站(zhan)(zhan)(zhan)。同時，根據《鋼鐵工(gong)(gong)業(ye)(ye)水(shui)(shui)污(wu)染(ran)物排放標(biao)準》和環保部門的(de)相關要(yao)求(qiu)，應(ying)實現總排放口的(de)零排放。

為(wei)實(shi)現總(zong)(zong)排放(fang)(fang)口(kou)零排放(fang)(fang)，本工(gong)(gong)(gong)(gong)程(cheng)擬(ni)將新建工(gong)(gong)(gong)(gong)程(cheng)所產(chan)生(sheng)(sheng)的(de)工(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)制(zhi)成純水(shui)(shui)(shui)(shui)(shui)(shui)(shui)供生(sheng)(sheng)產(chan)使(shi)用(yong)(yong)。多余的(de)工(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)采(cai)取常(chang)規處理(li)后和在(zai)制(zhi)取純水(shui)(shui)(shui)(shui)(shui)(shui)(shui)過程(cheng)中產(chan)生(sheng)(sheng)的(de)濃鹽水(shui)(shui)(shui)(shui)(shui)(shui)(shui)一起作(zuo)為(wei)回用(yong)(yong)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)使(shi)用(yong)(yong)。但(dan)經過全廠(chang)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)量(liang)(liang)平(ping)衡(heng)計算，排放(fang)(fang)的(de)工(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)全部(bu)處理(li)回收是(shi)完全可(ke)行(xing)的(de)。但(dan)是(shi)由于原先已建的(de)廠(chang)區(qu)工(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)量(liang)(liang)大(da)(da)于回用(yong)(yong)量(liang)(liang)，新建工(gong)(gong)(gong)(gong)程(cheng)為(wei)短流(liu)程(cheng)生(sheng)(sheng)產(chan)工(gong)(gong)(gong)(gong)藝，沒有燒結的(de)混合用(yong)(yong)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)和煉鋼熱潑(po)渣等直流(liu)用(yong)(yong)戶(該部(bu)分用(yong)(yong)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)與(yu)物料直接(jie)接(jie)觸，大(da)(da)部(bu)分被蒸發)，進一步加大(da)(da)了(le)工(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)與(yu)回用(yong)(yong)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)量(liang)(liang)之(zhi)間的(de)差值。即便已經將部(bu)分工(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)用(yong)(yong)于純水(shui)(shui)(shui)(shui)(shui)(shui)(shui)的(de)制(zhi)取，但(dan)工(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)量(liang)(liang)仍遠大(da)(da)于回用(yong)(yong)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)量(liang)(liang)，無法實(shi)現總(zong)(zong)排放(fang)(fang)口(kou)零排放(fang)(fang)。如果將剩余工(gong)(gong)(gong)(gong)業(ye)污(wu)(wu)水(shui)(shui)(shui)(shui)(shui)(shui)(shui)全部(bu)脫鹽制(zhi)后供生(sheng)(sheng)產(chan)使(shi)用(yong)(yong)，成本太高(gao)。

5.2 敞開式循環(huan)冷卻水(shui)(shui)系統及(ji)其補充水(shui)(shui)分析

5.2.1 凈循(xun)環冷卻水系統

凈(jing)循環冷(leng)卻水系統補充水一般采用(yong)廠(chang)區工(gong)業(ye)新水。

在進行凈(jing)循(xun)環(huan)水(shui)(shui)補充水(shui)(shui)的計算前，先設定(ding)如下參數：凈(jing)循(xun)環(huan)冷卻水(shui)(shui)含鹽量(liang)為B，凈(jing)循(xun)環(huan)水(shui)(shui)系統(tong)(tong)濃縮倍數值設定(ding)為N1;凈(jing)循(xun)環(huan)冷卻水(shui)(shui)系統(tong)(tong)補充水(shui)(shui)用廠(chang)區(qu)工(gong)業新(xin)水(shui)(shui)，工(gong)業新(xin)水(shui)(shui)含鹽量(liang)設定(ding)為C。N1=B/C。[2][3]

凈循環冷卻水含鹽(yan)量(liang)B應符(fu)合(he)所需冷卻的工藝設備的最低(di)限度要求，即(ji)可認為B是恒定(ding)值。在這種條件下，如果(guo)工業新(xin)水的含鹽(yan)量(liang)越低(di)(水質好(hao))，則相(xiang)應的濃縮倍數也越大(da)，扣除蒸發因素(su)外所需補(bu)充的水量(liang)也就越少，其(qi)強制排污的水量(liang)也越少，所需的補(bu)充工業新(xin)水量(liang)也越少。

某鋼鐵公司新建項目工業(ye)(ye)凈循(xun)環水(shui)系統濃縮倍數與工業(ye)(ye)新水(shui)含鹽(yan)量降低(di)率的關系曲線，工業(ye)(ye)凈循(xun)環水(shui)含鹽(yan)量為設定(ding)值(Cl-為180 mg/L)。

可以看(kan)出(chu)，隨著工業新(xin)水含鹽(yan)量(liang)降低(di)率的升高(gao)，濃縮(suo)倍(bei)數的趨勢也在變大(da)，而且變大(da)的幅度更大(da)。

5.2.2 濁循環冷(leng)卻(que)水補充水的分析

濁(zhuo)循(xun)環(huan)冷卻水(shui)(shui)(shui)系統的(de)補充水(shui)(shui)(shui)通(tong)常采(cai)用(yong)敞(chang)開式(shi)凈循(xun)環(huan)冷卻水(shui)(shui)(shui)的(de)強制排(pai)污水(shui)(shui)(shui)，在凈循(xun)環(huan)強制排(pai)污水(shui)(shui)(shui)量無法滿足需(xu)求的(de)情況下(xia)，采(cai)用(yong)工業新水(shui)(shui)(shui)作(zuo)為補充水(shui)(shui)(shui)源。

在(zai)進行濁循(xun)環(huan)(huan)(huan)水(shui)(shui)補充水(shui)(shui)的(de)(de)計(ji)算(suan)前(qian)，先設定如下參(can)數(shu)(shu)：以經處理后的(de)(de)濁循(xun)環(huan)(huan)(huan)水(shui)(shui)含鹽量A為(wei)濁循(xun)環(huan)(huan)(huan)濃縮(suo)倍(bei)數(shu)(shu)計(ji)算(suan)的(de)(de)參(can)照量，濁循(xun)環(huan)(huan)(huan)濃縮(suo)倍(bei)數(shu)(shu)值設定為(wei)N2;相關凈循(xun)環(huan)(huan)(huan)冷(leng)卻(que)(que)水(shui)(shui)含鹽量設定為(wei)B，凈循(xun)環(huan)(huan)(huan)水(shui)(shui)系統濃縮(suo)倍(bei)數(shu)(shu)值設定為(wei)N1;凈循(xun)環(huan)(huan)(huan)冷(leng)卻(que)(que)水(shui)(shui)系統補充水(shui)(shui)采用廠區工業(ye)新水(shui)(shui)，工業(ye)新水(shui)(shui)含鹽量設定為(wei)C。

N1=B/C，N2=A/B→N2= A/(C·N1)

由上面的計算可以(yi)得出以(yi)下推(tui)論：

①如果(guo)C越(yue)低(di)(di)，則N2也越(yue)高，說明當(dang)凈(jing)循(xun)環排污水(shui)量已(yi)經無法滿足(zu)濁(zhuo)循(xun)環補水(shui)需求，采用工(gong)業(ye)新(xin)水(shui)作為濁(zhuo)循(xun)環水(shui)系統的補水(shui)時(shi)，降低(di)(di)工(gong)業(ye)新(xin)水(shui)的含鹽(yan)量，也可以提高濁(zhuo)循(xun)環水(shui)濃縮倍數(shu)，減少強制排污水(shui)量，從而(er)降低(di)(di)補充水(shui)量;

②通常情況下A>C，理論計算上來說，當A/CN1，則N2>1，但當N2<1時，濃縮倍數沒有意義;一般敞開式凈循環水濃縮倍數N1=4~5，也就是說只有在濁循環水含鹽量A是工業新水含鹽量C的4~5倍以上時，濁循環水濃縮倍數才可能>1，濁循環說濃縮倍數才有意義;反之，當濁循環水的含鹽量不是工業新水含鹽量的4~5倍以上時，不應使用凈循環強制排污水作為濁循環水系統的補充水，而應考慮采用水質更加好的工業新水。

  使用微信“掃一掃”功能添加“谷騰環保網”

相關文章