美国页岩气开发的水污染风险成因、争议及对中国的启示  

Causes of water contamination risks from shale gas development and debate on it in the United States and implications for China

作　　者：夏良玉[1] XIA Liang-yu(School of Economics and Management,China University of Petroleum ( Beijing),Beijing 102249,China)

机构地区：[1]中国石油大学(北京)经济管理学院

出　　处：《中国人口·资源与环境》2019年第6期31-39,共9页China Population,Resources and Environment

基　　金：国家科技重大专项专题“页岩气开发项目经济评价”(批准号:2011ZX05018-005-01)

摘　　要：国内一些文献在讨论美国页岩气开发环境影响问题时,选择了这样的预设立场,即认为页岩气开发的环境危害显著高于常规油气开发。事实上,无论在美国的研究领域还是在实践层面,对这个问题的认识都充满了争议,争议的源头和焦点是页岩气开发的潜在水污染风险。为了客观认识页岩气开发过程中的水污染风险问题,本文从污染成因入手,聚焦争议的关键点和产生来源,并在梳理各方观点和证据的基础上得出几点认识:①关于地表泄露,并没有证据表明与水力压裂相关的泄露对水环境的负面影响程度高于其他作业环节,也不能判定页岩气开发的水污染风险高于常规油气;②关于地下泄露,目前能够认定甲烷气是潜在的地下污染源,产生的原因是完井缺陷和特殊地质条件,而源自压裂液和深层含盐地层水的污染尚未得到证实;③尽管来自液体污染物的地下水污染尚未在页岩气采区得到证实,但当地下水层和压裂作业层距离过近时,存在水污染的可能。在中国页岩气开发环境影响防治过程中,除了要借鉴美国经验,还要注意到两国之间的差异,这些差异有可能让相似根源的问题产生相异的结果。建议考虑以下几方面差异:首先,要认识到规制强度的差异,上述认识是在美国各州普遍进行严格监管的条件下得到的,如果监管放松,页岩气开发对环境的不利影响确实高于常规(非水力压裂)油气开发;其次,要重视中国特殊地质条件可能引发的新问题,如天然裂缝滑动导致生产套管变形甚至破裂、地下溶洞发育等会增大地下水污染的风险;最后,与美国不同,中国页岩气井场多位于丘陵或山地,还有一些气田临近人口稠密的村镇,这些将增加地表泄露风险和泄露发生后的补救难度。A preconceived viewpoint could be found in some articles in China that the negative environmental impacts form shale gas production will be more serious than from conventional oil and gas production.Actually,there is a substantial controversy regarding this topic in both academia and industry,and the potential risks on water quality are the focus of the debate.This paper aims at providing an objective understanding of the controversy through analyzing the causes of water contamination,and focusing on the key points and the reasons of the debate further.The conclusions are as follows:①No sufficient proof is found that the severity of impacts from surface spills related to the hydraulic fracturing process is higher than that from other processes,and it is not reliable that shale gas development poses no greater environmental risks than conventional oil and gas development.②As to the groundwater contamination risks,the methane could be recognized as a possible contamination source in case of cement integrity failures,together with special geological features,but no liquid contaminants from hydraulic fracturing water or produced water are found in groundwater in the vicinity of shale gas pads.③Nevertheless,it is rational that the risk from those liquid contaminants would increase with the decrease of the vertical separation between the usable water and the production zone.Based on these understandings,suggestions for shale gas industry in China considering the differences between China the United States are provided:first,regulatory strength is a key factor to the environmental consequences,and thus its differences between the two countries should be took into accounted;second,special geological characteristics of the shale plays in China may cause new problems,such as the deformation or rupture of production caused by fracking,and rock cavern development,which would increase the water contamination risk;finally,unlike the United States,shale gas fields in China are located mostly in hilly and mountainous regio

关 键 词：页岩气 环境影响 水污染风险 争议 

分 类 号：X37[环境科学与工程—环境工程]