給(gei)排(pai)水(shui)系統的(de)合理設(she)置及給(gei)排(pai)水(shui)管(guan)道的(de)管(guan)材、防腐、閥門等(deng)的(de)合理選擇，防止了地(di)下水(shui)和土壤受(shou)到污染，保(bao)證了石油化工企業安全運行。埋地(di)給(gei)排(pai)水(shui)管(guan)道用的(de)管(guan)材應(ying)根(gen)據(ju)內水(shui)壓(ya)力、流量、環境介質及管(guan)材材質等(deng)綜合因素確定。
1. 給排水系(xi)統
石(shi)化給(gei)排水(shui)(shui)(shui)系(xi)統(tong)(tong)(tong)一般可分為給(gei)水(shui)(shui)(shui)系(xi)統(tong)(tong)(tong)和排水(shui)(shui)(shui)系(xi)統(tong)(tong)(tong)。給(gei)水(shui)(shui)(shui)系(xi)統(tong)(tong)(tong)包括生活(huo)給(gei)水(shui)(shui)(shui)、生產給(gei)水(shui)(shui)(shui)、循環水(shui)(shui)(shui)、消防水(shui)(shui)(shui)及(ji)回用水(shui)(shui)(shui)系(xi)統(tong)(tong)(tong)。排水(shui)(shui)(shui)系(xi)統(tong)(tong)(tong)可分為含油(you)污水(shui)(shui)(shui)系(xi)統(tong)(tong)(tong)、生產污水(shui)(shui)(shui)系(xi)統(tong)(tong)(tong)、清(qing)凈雨(yu)水(shui)(shui)(shui)系(xi)統(tong)(tong)(tong)、生活(huo)污水(shui)(shui)(shui)系(xi)統(tong)(tong)(tong)等。
①. 含油污水(shui)系統主要(yao)排(pai)放各生產裝置、輔助設施排(pai)出的含油污水(shui)，含油污水(shui)通過排(pai)污井或漏(lou)斗(dou)收集，重力(li)流(liu)進入(ru)隔油池，預處理后由泵提升至廠區(qu)內污水(shui)處理場處理達(da)標后排(pai)放。裝置污染(ran)區(qu)15min 前的初(chu)期雨(yu)水(shui)也進入(ru)含油污水(shui)系統。
②. 生產污(wu)水系統主要排(pai)放(fang)裝置污(wu)染(ran)區15min以(yi)后的(de)后期雨水，通(tong)過明溝收集進入生產污(wu)水系統，經泵加壓提升至污(wu)水處(chu)(chu)理場處(chu)(chu)理達標后排(pai)放(fang)。
③. 清凈雨(yu)水(shui)系統為廠區道(dao)路(lu)雨(yu)水(shui)，通過(guo)管道(dao)收集后進(jin)入雨(yu)水(shui)調峰池，經監測(ce)無污染后可直接(jie)外排或(huo)處(chu)理后再利(li)用。
④. 生(sheng)(sheng)(sheng)(sheng)活污(wu)水(shui)(shui)系統(tong)(tong)(tong)來自廁所、食堂、浴室(shi)生(sheng)(sheng)(sheng)(sheng)活污(wu)水(shui)(shui)，經化糞池后(hou)壓力排往污(wu)水(shui)(shui)處理場的(de)生(sheng)(sheng)(sheng)(sheng)化池。生(sheng)(sheng)(sheng)(sheng)活污(wu)水(shui)(shui)需(xu)單(dan)獨(du)收集，個別生(sheng)(sheng)(sheng)(sheng)活污(wu)水(shui)(shui)需(xu)排入(ru)生(sheng)(sheng)(sheng)(sheng)產污(wu)水(shui)(shui)、含(han)油污(wu)水(shui)(shui)系統(tong)(tong)(tong)時，在(zai)接(jie)入(ru)前需(xu)設(she)水(shui)(shui)封設(she)施，以防止生(sheng)(sheng)(sheng)(sheng)產污(wu)水(shui)(shui)系統(tong)(tong)(tong)的(de)有害氣(qi)體竄(cuan)入(ru)生(sheng)(sheng)(sheng)(sheng)活設(she)施。
2. 管(guan)材選用(yong)
除生活(huo)給(gei)水管(guan)(guan)(guan)(guan)室內(nei)部(bu)分采(cai)用(yong)塑(su)料(liao)(liao)管(guan)(guan)(guan)(guan)外，其(qi)余給(gei)水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)一般鋼(gang)管(guan)(guan)(guan)(guan)，焊(han)(han)接(jie)(jie)(jie)連(lian)(lian)接(jie)(jie)(jie)。含(han)油污水、生產污水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)建議采(cai)用(yong)輸送流體(ti)用(yong)無縫鋼(gang)管(guan)(guan)(guan)(guan)，焊(han)(han)接(jie)(jie)(jie)連(lian)(lian)接(jie)(jie)(jie)，也有(you)的(de)(de)采(cai)用(yong)低壓(ya)流體(ti)輸送用(yong)焊(han)(han)接(jie)(jie)(jie)鋼(gang)管(guan)(guan)(guan)(guan)。雨水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)一般采(cai)用(yong)球(qiu)磨(mo)鑄(zhu)(zhu)鐵管(guan)(guan)(guan)(guan)，承插連(lian)(lian)接(jie)(jie)(jie)。球(qiu)墨(mo)鑄(zhu)(zhu)鐵管(guan)(guan)(guan)(guan)耐腐蝕性能(neng)較強、管(guan)(guan)(guan)(guan)壁(bi)較厚(hou)、對管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)基礎的(de)(de)要(yao)求較低、施工費(fei)用(yong)低。生活(huo)污水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)室內(nei)部(bu)分一般采(cai)用(yong)建筑排(pai)水用(yong)PVC-U管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)，粘接(jie)(jie)(jie)連(lian)(lian)接(jie)(jie)(jie)；室外部(bu)分一般采(cai)用(yong)低壓(ya)流體(ti)輸送用(yong)焊(han)(han)接(jie)(jie)(jie)鋼(gang)管(guan)(guan)(guan)(guan)，焊(han)(han)接(jie)(jie)(jie)連(lian)(lian)接(jie)(jie)(jie)，以避免過路時(shi)生活(huo)污水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)被壓(ya)損。鋼(gang)骨架增(zeng)強塑(su)料(liao)(liao)復(fu)合管(guan)(guan)(guan)(guan)作(zuo)為新型管(guan)(guan)(guan)(guan)材，具有(you)機械強度高、耐溫性能(neng)好、雙面防腐、節能(neng)等優點，適用(yong)于絕大部(bu)分石油化工給(gei)埋地(di)排(pai)水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)。常用(yong)地(di)下管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)材料(liao)(liao)的(de)(de)選用(yong)見表4.3.32。
3. 防腐蝕設計
給排水管(guan)道(dao)(dao)外防(fang)(fang)(fang)(fang)腐(fu)的好壞直接(jie)影響管(guan)道(dao)(dao)壽命(ming)，因此根據(ju)(ju)實際情況選擇合適防(fang)(fang)(fang)(fang)腐(fu)方案(an)及等級是非(fei)常(chang)重要的。根據(ju)(ju)SH／T 3022《石油化(hua)工(gong)設備和(he)管(guan)道(dao)(dao)涂料防(fang)(fang)(fang)(fang)腐(fu)蝕設計標(biao)準》，埋(mai)地管(guan)道(dao)(dao)外防(fang)(fang)(fang)(fang)腐(fu)可采用石油瀝(li)青(qing)漆、環(huan)氧煤瀝(li)青(qing)漆、聚乙烯(xi)膠黏帶進行防(fang)(fang)(fang)(fang)腐(fu)。石油瀝(li)青(qing)防(fang)(fang)(fang)(fang)腐(fu)涂層結(jie)構(gou)成(cheng)本低，但需(xu)在施(shi)(shi)工(gong)現場加熱(re)石油瀝(li)青(qing)，且對環(huan)境有一定(ding)的污染，已漸漸淡出市場。聚乙烯(xi)膠黏帶防(fang)(fang)(fang)(fang)腐(fu)層防(fang)(fang)(fang)(fang)腐(fu)性能(neng)優異，但其(qi)成(cheng)本高、施(shi)(shi)工(gong)工(gong)藝較復雜、焊縫處易形(xing)成(cheng)空鼓(gu)、補口操作復雜。環(huan)氧煤瀝(li)青(qing)防(fang)(fang)(fang)(fang)腐(fu)涂層結(jie)構(gou)成(cheng)本較聚乙烯(xi)膠黏帶低，具有一次成(cheng)膜厚、耐(nai)酸堿、施(shi)(shi)工(gong)簡單等優點(dian)，一般選用環(huan)氧煤瀝(li)青(qing)漆進行埋(mai)地管(guan)道(dao)(dao)防(fang)(fang)(fang)(fang)腐(fu)。管(guan)道(dao)(dao)穿井壁處需(xu)設置防(fang)(fang)(fang)(fang)水套(tao)管(guan)，防(fang)(fang)(fang)(fang)止管(guan)道(dao)(dao)泄漏(lou)。
