王春生 鄭杰 褚會娟 等
摘 要:在一定溫度和壓力條件下,集氣系統不可避免的會形成水合物。遼河油田曙光采油廠在冬季生產過程中,由于溫度低、部分管線埋地淺、尾氣攜液量大等原因,在輸送過程中易形成游離水及水合物,在冬季生產過程中經常發生凍堵現象。預防天然氣水合物形成的方法有很多,其中在氣井中注入水合物抑制劑的方法較為普遍。現針對此問題,以水合物減少的百分數為衡量標準,通過軟件計算,對常用的水合物抑制劑進行篩選,對篩選出的凍堵防治抑制劑進行優化用量并制定凍堵防治方案,以達到減少凍堵情況發生的目的,此舉對曙光采油廠實際運行具有一定的指導意義。
關 鍵 詞:水合物;游離水;凍堵;抑制劑
中圖分類號:TE 832 文獻標識碼: A 文章編號: 1671-0460(2015)10-2478-02
Screening and Application of Hydrate Inhibitors in the Fire Flooding
Exhaust Gas Collection Pipe Networks of Heavy Oil
WANG Chun-sheng1,ZHENG Jie1,2,Chu Hui-juan1,SUN Ying-fan1,TIAN Ming-lei1,XV Yu-jian1
(1. Northeast Petroleum University, Heilongjiang Daqing 163000,China;
2. PetroChina Daqing Oilfield Co., Ltd., Heilongjiang Daqing 163000,China)
Abstract: Under a certain temperature and pressure, the gas collection system will inevitably produce hydrates. During the production in winter in Shuguang oil production plant of Liaohe oilfield, due to low temperature, shallow buried depth of the pipelines, and big liquid carrying quantity of exhaust gas, hydrates and free water always formed in the pipelines, so the frozen blocking phenomenon frequently took place. There are many ways to prevent the formation of natural gas hydrates, and the method of injecting hydrate inhibitor in gas wells is relatively common. In view of the actual situation, in order to achieve the purpose of reducing the occurrence of the frozen blocking condition, the hydrate inhibitors were screened, the dosage was optimized, and the hydrate control scheme was worked out.
Key words: Hydrates; Free water; Frozen blocking; Inhibitors
預防水合物使用最多的方法是注入化學抑制劑。根據化學抑制劑作用的機理不同,可將其分為熱力學抑制劑、動力學抑制劑、阻聚劑和復合型抑制劑[1]。
國內外研究和應用實踐表明:熱力學抑制劑需要在高濃度下才能見效、成本較高、其本身在起到預防水合物生成的同時也能起到溶解水合物的作用,但仍是目前應用最為廣泛和有效的水合物抑制劑。低用量動力學水合物抑制劑(LDHI)還不成熟,并未得到廣泛應用[2-4]。當前很多現場如多相混輸管線、氣井等大多還采用甲醇、乙二醇等熱力學抑制劑。而目前出現的防聚劑是僅在油和水共存時才能防止氣體水合物的生成,作用效果與油相組成、含水量和水相含鹽量有關,因此在實際應用中也存在諸多限制,綜合現場實際情況,本次研究使用的熱力學抑制劑。……