給(gei)排水(shui)系(xi)統的(de)(de)合理(li)設置及給(gei)排水(shui)管道的(de)(de)管材、防(fang)腐、閥門等的(de)(de)合理(li)選擇，防(fang)止了地下水(shui)和土壤受到污染，保證了石油(you)化工企業安全運行。埋地給(gei)排水(shui)管道用的(de)(de)管材應根(gen)據內水(shui)壓(ya)力(li)、流量、環境(jing)介質及管材材質等綜(zong)合因素確定。
1. 給排水(shui)系統
石化給排(pai)(pai)(pai)水系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)一(yi)般(ban)可分為給水系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)和排(pai)(pai)(pai)水系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)。給水系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)包括生(sheng)活給水、生(sheng)產給水、循環(huan)水、消防(fang)水及回用(yong)水系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)。排(pai)(pai)(pai)水系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)可分為含油污水系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)、生(sheng)產污水系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)、清凈雨水系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)、生(sheng)活污水系(xi)(xi)(xi)(xi)統(tong)(tong)(tong)等(deng)。
①. 含(han)油污水(shui)(shui)(shui)系統主要排(pai)放(fang)(fang)各(ge)生產裝置、輔助設施(shi)排(pai)出的含(han)油污水(shui)(shui)(shui)，含(han)油污水(shui)(shui)(shui)通過排(pai)污井或漏斗收集，重力流進入隔油池(chi)，預處(chu)(chu)(chu)理后由泵提升至廠區(qu)(qu)內(nei)污水(shui)(shui)(shui)處(chu)(chu)(chu)理場處(chu)(chu)(chu)理達標后排(pai)放(fang)(fang)。裝置污染區(qu)(qu)15min 前的初期雨水(shui)(shui)(shui)也進入含(han)油污水(shui)(shui)(shui)系統。
②. 生(sheng)產污(wu)水系(xi)統(tong)主要排(pai)放裝置污(wu)染(ran)區15min以后的后期雨水，通過明溝收集(ji)進(jin)入生(sheng)產污(wu)水系(xi)統(tong)，經泵加壓提升至污(wu)水處理場處理達標后排(pai)放。
③. 清凈雨水系統為廠區道路雨水，通(tong)過管道收集后進入雨水調(diao)峰池，經(jing)監(jian)測無(wu)污染后可直接外(wai)排或處理后再利用。
④. 生(sheng)活污(wu)(wu)(wu)水(shui)系(xi)統來自廁所、食堂、浴室生(sheng)活污(wu)(wu)(wu)水(shui)，經化糞池(chi)后壓力(li)排往污(wu)(wu)(wu)水(shui)處理(li)場的(de)生(sheng)化池(chi)。生(sheng)活污(wu)(wu)(wu)水(shui)需單獨收集，個(ge)別(bie)生(sheng)活污(wu)(wu)(wu)水(shui)需排入(ru)生(sheng)產(chan)(chan)污(wu)(wu)(wu)水(shui)、含油污(wu)(wu)(wu)水(shui)系(xi)統時，在(zai)接(jie)入(ru)前(qian)需設水(shui)封設施，以防止生(sheng)產(chan)(chan)污(wu)(wu)(wu)水(shui)系(xi)統的(de)有害(hai)氣體竄入(ru)生(sheng)活設施。
2. 管(guan)材選用(yong)
除生(sheng)活(huo)給水管(guan)(guan)(guan)(guan)室(shi)內部(bu)分(fen)(fen)采用(yong)(yong)(yong)(yong)塑料(liao)(liao)管(guan)(guan)(guan)(guan)外，其余(yu)給水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)一(yi)般(ban)(ban)鋼(gang)(gang)(gang)管(guan)(guan)(guan)(guan)，焊(han)接(jie)(jie)連接(jie)(jie)。含油污(wu)水、生(sheng)產污(wu)水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)建議采用(yong)(yong)(yong)(yong)輸送流(liu)體用(yong)(yong)(yong)(yong)無縫鋼(gang)(gang)(gang)管(guan)(guan)(guan)(guan)，焊(han)接(jie)(jie)連接(jie)(jie)，也有的(de)采用(yong)(yong)(yong)(yong)低(di)(di)壓流(liu)體輸送用(yong)(yong)(yong)(yong)焊(han)接(jie)(jie)鋼(gang)(gang)(gang)管(guan)(guan)(guan)(guan)。雨(yu)水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)一(yi)般(ban)(ban)采用(yong)(yong)(yong)(yong)球磨鑄(zhu)鐵(tie)管(guan)(guan)(guan)(guan)，承(cheng)插連接(jie)(jie)。球墨鑄(zhu)鐵(tie)管(guan)(guan)(guan)(guan)耐腐蝕性能(neng)較(jiao)強(qiang)、管(guan)(guan)(guan)(guan)壁(bi)較(jiao)厚、對管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)基礎的(de)要求較(jiao)低(di)(di)、施工費用(yong)(yong)(yong)(yong)低(di)(di)。生(sheng)活(huo)污(wu)水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)室(shi)內部(bu)分(fen)(fen)一(yi)般(ban)(ban)采用(yong)(yong)(yong)(yong)建筑排(pai)水用(yong)(yong)(yong)(yong)PVC-U管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)，粘(zhan)接(jie)(jie)連接(jie)(jie)；室(shi)外部(bu)分(fen)(fen)一(yi)般(ban)(ban)采用(yong)(yong)(yong)(yong)低(di)(di)壓流(liu)體輸送用(yong)(yong)(yong)(yong)焊(han)接(jie)(jie)鋼(gang)(gang)(gang)管(guan)(guan)(guan)(guan)，焊(han)接(jie)(jie)連接(jie)(jie)，以避(bi)免過路(lu)時生(sheng)活(huo)污(wu)水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)被壓損。鋼(gang)(gang)(gang)骨(gu)架增強(qiang)塑料(liao)(liao)復合管(guan)(guan)(guan)(guan)作為新型管(guan)(guan)(guan)(guan)材，具有機械強(qiang)度高、耐溫(wen)性能(neng)好(hao)、雙面防腐、節能(neng)等優(you)點，適用(yong)(yong)(yong)(yong)于(yu)絕大部(bu)分(fen)(fen)石油化工給埋地排(pai)水管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)。常用(yong)(yong)(yong)(yong)地下管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)材料(liao)(liao)的(de)選用(yong)(yong)(yong)(yong)見表4.3.32。
3. 防(fang)腐蝕設計
給排水(shui)管道(dao)(dao)外(wai)防(fang)(fang)腐(fu)的好壞(huai)直接影響管道(dao)(dao)壽命，因此根據實際情況選擇(ze)合適防(fang)(fang)腐(fu)方案及(ji)等(deng)級是非常重(zhong)要的。根據SH／T 3022《石油(you)化工(gong)(gong)設(she)備和管道(dao)(dao)涂(tu)料(liao)防(fang)(fang)腐(fu)蝕設(she)計標準》，埋(mai)地(di)管道(dao)(dao)外(wai)防(fang)(fang)腐(fu)可采用(yong)石油(you)瀝(li)(li)青漆(qi)、環(huan)氧煤(mei)瀝(li)(li)青漆(qi)、聚(ju)乙烯膠(jiao)黏(nian)帶(dai)進行(xing)防(fang)(fang)腐(fu)。石油(you)瀝(li)(li)青防(fang)(fang)腐(fu)涂(tu)層(ceng)結(jie)構成本低，但需在(zai)施工(gong)(gong)現場加熱石油(you)瀝(li)(li)青，且對(dui)環(huan)境有一(yi)(yi)定(ding)的污染，已漸(jian)漸(jian)淡出(chu)市場。聚(ju)乙烯膠(jiao)黏(nian)帶(dai)防(fang)(fang)腐(fu)層(ceng)防(fang)(fang)腐(fu)性能優異(yi)，但其成本高、施工(gong)(gong)工(gong)(gong)藝較復(fu)雜、焊縫(feng)處易形(xing)成空鼓(gu)、補口操作復(fu)雜。環(huan)氧煤(mei)瀝(li)(li)青防(fang)(fang)腐(fu)涂(tu)層(ceng)結(jie)構成本較聚(ju)乙烯膠(jiao)黏(nian)帶(dai)低，具有一(yi)(yi)次成膜厚、耐酸(suan)堿、施工(gong)(gong)簡單等(deng)優點，一(yi)(yi)般(ban)選用(yong)環(huan)氧煤(mei)瀝(li)(li)青漆(qi)進行(xing)埋(mai)地(di)管道(dao)(dao)防(fang)(fang)腐(fu)。管道(dao)(dao)穿井(jing)壁處需設(she)置防(fang)(fang)水(shui)套管，防(fang)(fang)止管道(dao)(dao)泄(xie)漏。
