页岩气开发过程中的水处理技术探讨

Discussion on Water Treatment Technology in Shale Gas Development

页岩气开发普遍采用水力压裂开采方式,开发过程中会产生大量压裂返排液,压裂返排液中悬浮物、总溶解固体、金属离子和有机物等含量都较高,并且组成成分复杂,这些因素都决定着处理后的水是否能够有效再利用;然而目前压裂返排液回收再利用的基本方法由于没有彻底解决清除盐和其他化学成分的问题,还存在一定局限性。针对压裂返排液进行净化处理的主要方法有过滤法、化学沉淀法、热技术法、膜过滤技术法等。美国的废水管理方法主要包括尽可能降低生产废水量、循环回收利用气井作业过程中的水、在生产场地采用储水罐或储水池、对作业外水进行处理和再利用。相比于美国,我国页岩气起步较晚,经验欠缺,故为了确保我国页岩气的长期开采,不仅要选择合适的水处理方案,而且还应启动相应的监管工作,才能减小其对环境造成的污染和破坏。

The hydraulic fracturing method is widely used in shale gas development ana huge amounts of fracturing flowbaclc fluid is produced in the development process. The flow- back fluid usually contains high content of suspended particles, total dissolved solids, metaiic ions and organic matter and its composition is complex. All of these determine whether the treated water can be reused effectively. However, the basic method so far for fracturing fluid recycling still has some limitations, for it can not completely solve the problem of-disposal salt and other chemical constituents. The major purification methods of fracturing fluid are filtering method, chemical precipitation, thermal technology, membrane filtration, etc. The wastewater management methods in America mainly include minimizing wastewater proauction, recycling water produced in gas well operation process, using storage tanks or reservoirs in production area and recycling operating water. Compared with the United States, the shale gas production in China starts late and is inexperience. Thus, in order to ensure the long-term exploitation of-shale gas in China, not only appropriate water treatment technology should Be chosen but also the corresponding supervision work should be started, so as to reduce the pollution and damage caused to environment.