美国页岩气返排废水处理技术探讨及启示

Discuss and Enlightenment of the Treatment Technologies of Shale Gas Flowback Wastewater in United States

介绍了美国页岩气返排废水处置方式,如深井回注、部分处理后内部回用、处理达标后外排;总结了其先进的返排废水处理新技术,包括臭氧催化氧化、超声波-臭氧氧化-电絮凝-反渗透、机械蒸汽再压缩、步进沉淀、移动电凝、生物降解-离子交换、纳米滤膜、智能海绵、热蒸馏-磁过滤等技术,为实现我国页岩气开发跨越式发展提供了技术支撑。结合我国实际情况及示范工程的现场经验,提出了环境监测及处理与开发同步实施、首选在井场内重复利用页岩气废水、自主研发多种处理方法并行的组合工艺、三级处理无法回用的废水后外排、回用已处理的其他途径废水等建议,以期使我国在大力开发页岩气的同时,可保护生态环境及降低处理成本。

The disposal way of shale gas flowback wastewater in the United States were described, such as deep well reinjection, internal recycling after partial processing, and discharging after reaching the emission standard. Moreover, the advanced new technologies of shale gas flowback water in United States were reviewed, including catalytic ozonation, ultrasonic/ozone oxidation/electric flocculation/reverse osmosis, mechanical vapor recompression,step-by-step precipitation, mobile electrocoagulation, biodegradation/ion exchange, nano filtering membrane, smart sponge, thermal distillation/magnetic filtration and so on, which can provide technical support to shale gas industry in China. Appropriate recommendations were given after combining with the actual situation in China and on-site experience of demonstration project. For example, synchronous implementation with environmental monitoring and development, reusing the shale gas wastewater in well site, independent research the group technology of multiprocessing, discharging after tertiary treatment, recycling treated wastewater from other sources, and so forth. These suggestions can protect the ecological environment and reduce the processing cost during the exploitation of shale gas in China.