摘要
页岩油和页岩气开采过程产生的大量废料,如果不经过处理,将对地下水造成污染.首先,介绍了页岩油气的分布和赋存机理,以及地面干馏、水平钻井和水力压裂等开采技术;然后,阐述了页岩油气在现场准备、钻井压裂、采油采气等不同开采环节中的主要污染源;进而讨论了页岩油气开采中主要的地下水污染物,分别是有机污染物、重金属和放射性物质,同时阐述了其带来的地下水污染长期性、隐蔽性和差异性的特点;最后,从技术改进和废料处理等方面对页岩油气开采对地下水污染的防治手段进行了展望.
Abstract
The extraction of shale oil and gas produces a large number of waste materials that are generally discharged into the groundwater environment,causing contamination of groundwater which threatens human health.First,the distribution and storage mechanism of shale oil and gas,as well as the extraction technologies,which include oil shale retorting,horizontal drilling,and hydraulic fracturing,are introduced.Then,various events that may cause groundwater pollution and the main sources of contamination in the extraction processes,which consist of preparations,drilling and fracturing,and capture of shale oil and gas,are summarized.Afterwards,three types of groundwater pollutants caused by shale oil and gas exploitation,which are organic contaminants,heavy metals,and radioactive material,are discussed,and the characteristics of groundwater contamination are expounded.Finally,the prospect of groundwater pollution research in the exploitation of shale oil and gas is proposed from the perspectives of technological improvement and waste treatment.