給(gei)排水系統的合理設置及給(gei)排水管道的管材(cai)、防(fang)腐、閥門(men)等的合理選擇,防(fang)止(zhi)了地下水和(he)土壤受到(dao)污染(ran),保(bao)證了石油化(hua)工企業安全(quan)運(yun)行。埋地給(gei)排水管道用的管材(cai)應根據內水壓力、流量、環境介質(zhi)及管材(cai)材(cai)質(zhi)等綜合因素確定。
1. 給排水(shui)系統
石(shi)化給排(pai)水(shui)(shui)(shui)(shui)(shui)系統一般(ban)可(ke)分(fen)(fen)為給水(shui)(shui)(shui)(shui)(shui)系統和排(pai)水(shui)(shui)(shui)(shui)(shui)系統。給水(shui)(shui)(shui)(shui)(shui)系統包括(kuo)生活(huo)(huo)給水(shui)(shui)(shui)(shui)(shui)、生產給水(shui)(shui)(shui)(shui)(shui)、循環水(shui)(shui)(shui)(shui)(shui)、消防水(shui)(shui)(shui)(shui)(shui)及回(hui)用(yong)水(shui)(shui)(shui)(shui)(shui)系統。排(pai)水(shui)(shui)(shui)(shui)(shui)系統可(ke)分(fen)(fen)為含油污水(shui)(shui)(shui)(shui)(shui)系統、生產污水(shui)(shui)(shui)(shui)(shui)系統、清凈雨水(shui)(shui)(shui)(shui)(shui)系統、生活(huo)(huo)污水(shui)(shui)(shui)(shui)(shui)系統等。
①. 含油污水系(xi)統主要(yao)排(pai)(pai)(pai)放(fang)(fang)各(ge)生產裝(zhuang)置、輔助設施排(pai)(pai)(pai)出(chu)的(de)含油污水,含油污水通過排(pai)(pai)(pai)污井或漏斗收集(ji),重力流進(jin)入隔油池,預處理后(hou)由泵提升至(zhi)廠(chang)區內污水處理場處理達標后(hou)排(pai)(pai)(pai)放(fang)(fang)。裝(zhuang)置污染區15min 前的(de)初(chu)期雨水也進(jin)入含油污水系(xi)統。
②. 生(sheng)(sheng)產(chan)污(wu)水(shui)系(xi)統(tong)主要(yao)排(pai)放裝置污(wu)染區15min以(yi)后(hou)的后(hou)期雨水(shui),通過(guo)明溝收集進入生(sheng)(sheng)產(chan)污(wu)水(shui)系(xi)統(tong),經泵加壓提升(sheng)至(zhi)污(wu)水(shui)處(chu)理(li)場(chang)處(chu)理(li)達標后(hou)排(pai)放。
③. 清(qing)凈雨(yu)水系統為廠區(qu)道路雨(yu)水,通過(guo)管道收集(ji)后進入雨(yu)水調(diao)峰池,經(jing)監測無污染(ran)后可(ke)直接外排或處理后再(zai)利用。
④. 生(sheng)(sheng)活污(wu)(wu)(wu)水(shui)系(xi)(xi)統(tong)來自廁所(suo)、食(shi)堂、浴室(shi)生(sheng)(sheng)活污(wu)(wu)(wu)水(shui),經(jing)化(hua)糞(fen)池(chi)后壓力排往(wang)污(wu)(wu)(wu)水(shui)處理(li)場的(de)生(sheng)(sheng)化(hua)池(chi)。生(sheng)(sheng)活污(wu)(wu)(wu)水(shui)需(xu)單(dan)獨收(shou)集(ji),個別生(sheng)(sheng)活污(wu)(wu)(wu)水(shui)需(xu)排入生(sheng)(sheng)產污(wu)(wu)(wu)水(shui)、含油污(wu)(wu)(wu)水(shui)系(xi)(xi)統(tong)時,在接入前需(xu)設水(shui)封(feng)設施(shi),以防止生(sheng)(sheng)產污(wu)(wu)(wu)水(shui)系(xi)(xi)統(tong)的(de)有害氣體(ti)竄入生(sheng)(sheng)活設施(shi)。
2. 管材選用(yong)
除生活給(gei)水(shui)(shui)管(guan)(guan)(guan)(guan)室內部分采(cai)用(yong)(yong)(yong)(yong)塑(su)料管(guan)(guan)(guan)(guan)外,其余(yu)給(gei)水(shui)(shui)管(guan)(guan)(guan)(guan)道一(yi)般鋼管(guan)(guan)(guan)(guan),焊(han)接(jie)連接(jie)。含油(you)(you)污(wu)(wu)水(shui)(shui)、生產污(wu)(wu)水(shui)(shui)管(guan)(guan)(guan)(guan)道建議采(cai)用(yong)(yong)(yong)(yong)輸(shu)送流體用(yong)(yong)(yong)(yong)無縫(feng)鋼管(guan)(guan)(guan)(guan),焊(han)接(jie)連接(jie),也有的(de)采(cai)用(yong)(yong)(yong)(yong)低(di)壓(ya)(ya)流體輸(shu)送用(yong)(yong)(yong)(yong)焊(han)接(jie)鋼管(guan)(guan)(guan)(guan)。雨水(shui)(shui)管(guan)(guan)(guan)(guan)道一(yi)般采(cai)用(yong)(yong)(yong)(yong)球磨鑄(zhu)鐵(tie)管(guan)(guan)(guan)(guan),承插(cha)連接(jie)。球墨鑄(zhu)鐵(tie)管(guan)(guan)(guan)(guan)耐腐蝕性能(neng)較(jiao)強、管(guan)(guan)(guan)(guan)壁較(jiao)厚、對管(guan)(guan)(guan)(guan)道基礎的(de)要求較(jiao)低(di)、施(shi)工(gong)費用(yong)(yong)(yong)(yong)低(di)。生活污(wu)(wu)水(shui)(shui)管(guan)(guan)(guan)(guan)道室內部分一(yi)般采(cai)用(yong)(yong)(yong)(yong)建筑排水(shui)(shui)用(yong)(yong)(yong)(yong)PVC-U管(guan)(guan)(guan)(guan)道,粘接(jie)連接(jie);室外部分一(yi)般采(cai)用(yong)(yong)(yong)(yong)低(di)壓(ya)(ya)流體輸(shu)送用(yong)(yong)(yong)(yong)焊(han)接(jie)鋼管(guan)(guan)(guan)(guan),焊(han)接(jie)連接(jie),以避免過(guo)路時生活污(wu)(wu)水(shui)(shui)管(guan)(guan)(guan)(guan)道被(bei)壓(ya)(ya)損(sun)。鋼骨架增(zeng)強塑(su)料復合管(guan)(guan)(guan)(guan)作為新型(xing)管(guan)(guan)(guan)(guan)材,具(ju)有機械強度(du)高、耐溫性能(neng)好、雙面防腐、節能(neng)等優點,適用(yong)(yong)(yong)(yong)于絕(jue)大部分石油(you)(you)化(hua)工(gong)給(gei)埋地排水(shui)(shui)管(guan)(guan)(guan)(guan)道。常用(yong)(yong)(yong)(yong)地下(xia)管(guan)(guan)(guan)(guan)道材料的(de)選用(yong)(yong)(yong)(yong)見表4.3.32。
3. 防腐蝕(shi)設計
給排水(shui)管(guan)(guan)(guan)道外防(fang)(fang)腐(fu)(fu)(fu)的好壞直(zhi)接影響(xiang)管(guan)(guan)(guan)道壽命,因此(ci)根(gen)據實際情況選擇合適(shi)防(fang)(fang)腐(fu)(fu)(fu)方案及等(deng)級是非常(chang)重(zhong)要的。根(gen)據SH/T 3022《石油(you)化工(gong)設備和管(guan)(guan)(guan)道涂料(liao)防(fang)(fang)腐(fu)(fu)(fu)蝕設計標(biao)準》,埋地(di)管(guan)(guan)(guan)道外防(fang)(fang)腐(fu)(fu)(fu)可采用石油(you)瀝青(qing)(qing)漆、環氧(yang)煤瀝青(qing)(qing)漆、聚乙烯(xi)膠(jiao)黏帶(dai)進行防(fang)(fang)腐(fu)(fu)(fu)。石油(you)瀝青(qing)(qing)防(fang)(fang)腐(fu)(fu)(fu)涂層結(jie)構(gou)成本(ben)低,但(dan)需在施工(gong)現(xian)場加熱(re)石油(you)瀝青(qing)(qing),且對環境有一(yi)定的污染(ran),已漸(jian)漸(jian)淡(dan)出市場。聚乙烯(xi)膠(jiao)黏帶(dai)防(fang)(fang)腐(fu)(fu)(fu)層防(fang)(fang)腐(fu)(fu)(fu)性能優異,但(dan)其成本(ben)高、施工(gong)工(gong)藝較復(fu)雜(za)、焊縫處易形(xing)成空鼓、補口操(cao)作復(fu)雜(za)。環氧(yang)煤瀝青(qing)(qing)防(fang)(fang)腐(fu)(fu)(fu)涂層結(jie)構(gou)成本(ben)較聚乙烯(xi)膠(jiao)黏帶(dai)低,具有一(yi)次成膜厚、耐酸堿、施工(gong)簡(jian)單等(deng)優點,一(yi)般選用環氧(yang)煤瀝青(qing)(qing)漆進行埋地(di)管(guan)(guan)(guan)道防(fang)(fang)腐(fu)(fu)(fu)。管(guan)(guan)(guan)道穿井壁處需設置(zhi)防(fang)(fang)水(shui)套管(guan)(guan)(guan),防(fang)(fang)止(zhi)管(guan)(guan)(guan)道泄漏。