国内外页岩气开发环境管理现状及对比

Domestic and foreign environmental management of shale gas development:Status and comparison

为了推进页岩气绿色开发,需要建立系统完整的页岩气开发环境监管体系。为此,分析了页岩气开发面临的主要环境影响,系统对比研究了中国、美国、加拿大的页岩气开发相关环保政策法规与标准规范,在废水外排、废水地下回注、压裂作业风险管控、废气排放、废物现场储存、固废利用与处置、场地修复与恢复、生态红线与敏感目标保护等方面开展了适应性对标分析,进而提出了针对中国页岩气开发的环境管理建议。研究结果表明:①页岩气开发需防范压裂作业、压裂返排液处理、含油岩屑处置等多方面的环境影响和风险;②美国、加拿大的污染物排放标准遵循“技术强制”原则,实施地下回注控制、压裂作业风险管控、绿色完井、多途径利用和处置含油岩屑等全过程精细化管控,行业针对性和操作性强;③中国明确了页岩气开发环境管理的思路和原则性要求,但缺乏专项适用的环保标准规范,环境管理还存在着空白;④建议制订页岩气开采污染物排放标准,规定溶解性总固体、氯化物等废水特征污染物限值,明确含油岩屑处置、温室气体排放等管控要求;⑤应建立并完善废水地下回注环境监管体系、水力压裂作业环境风险管控体系,制订压裂液配方披露指南,制订含油岩屑多途径资源化利用污染控制技术规范,形成生态环境保护全链条系列标准规范。结论认为,中国应借鉴国外成熟的精细化环境管理经验,加快制修订页岩气开发相关环保标准,以实现页岩气开发全过程环境监管。

In order to promote the green development of shale gas,it is necessary to establish a systematic and complete environment supervision system of shale gas development.In this paper,the main environmental influences in the development of shale gas are analyzed.Then,environmental protection policies,laws,regulations,standards and specifications related to shale gas development are systematically compared between China,the USA,and Canada.In addition,adaptability benchmarking analysis is carried out from the aspects of wastewater discharge,wastewater reinjection,fracturing risk control,waste gas emission,on-site waste storage,solid waste utilization and disposal,site remediation and restoration,ecological redline and sensitive target protection.Finally,suggestions on the environmental management of shale gas development in China are proposed.And the following research results are obtained.First,shale gas development shall avoid environmental influences and risks in terms of fracturing operation,flowback fracturing fluid treatment and oily cutting disposal.Second,in the USA and Canada,the pollutant discharge standards follow the principle of technology forcing,and whole-process fine control of underground reinjection control,fracturing risk control,green well completion,multi-way utilization and oily cutting disposal is implemented with strong industrial pertinence and operability.Third,China has determined the ideas and principle requirements on the environmental management of shale gas development,but lacks special suitable environmental protection standards and specifications,and there is a blank in environmental management.Fourth,it is recommended to formulate a pollutant discharge standard of shale gas development,define the limit characteristic pollutant of wastewater(e.g.total dissolved solid and chloride),and clarify control requirements of oily cutting disposal and greenhouse gas emission.Fifth,it is suggested to establish and improve an environment monitoring system of wastewater reinjection and the environment risk control system of hydraulic fracturing operation and formulate the disclosure guideline of fracturing fluid formula and the multi-way resource utilization and pollution control technological specifications of oily cutting,so as to form a whole-chain standard and specification series of ecological environmental protection.In conclusion,China shall learn from foreign mature experiences in fine environmental management and speed up the formulation of environmental protection standards related to shale gas development,so as to realize the whole-process environment supervision of shale gas development.