页岩气勘探开发过程中的环境影响

当前,我国正积极推进页岩气资源的勘探和开发工作,但其对环境的影响尚缺乏科学评价和规范管理。在系统分析页岩气勘探开发主要流程:井场选址与建设、水平井钻井、水力压裂和投产等的基础上,辨识了其造成生态破坏和环境污染的主要因素以及可借鉴的技术和经验。结合我国页岩气资源的分布和勘探开发现状,从法规政策、企业责任以及技术创新三个层面,提出我国页岩气开发过程中环境保护和管理应努力的方向。     

Framing Shale Gas for Policy-Making in Poland

Despite enthusiasm about new gas reserves, shale gas has not come to Poland without controversies. This study examines how shale gas has been framed as a public issue by political and business elites, experts, local communities and civil society organizations. Through a frame analysis, we found three main frames about shale gas: shale gas as a novel economic resource, as a strategic resource for energy security and as a threat. However, only the first two frames, proposed by political and business elites, have shaped the policy process. The third frame, constructed by local actors and civil society groups, has had minimal impact. We explain this exclusion drawing on the deficit model of risk communication. This approach reveals that Polish experts, and business and political actors, during their interactions with local groups, have framed proponents of the threat frame as ‘incompetent actors’ effectively excluding the threat frame from policy processes.     

潜流湿地中填料的理化作用及对植物生长的影响

填料是潜流湿地的重要组成部分,它不但直接参与污染物的去除,而且对植物的生长和生理活动产生重要影响.本研究采用河北围场产沸石和秦皇岛产页岩,通过X射线荧光光谱和X射线衍射分析,确定了2种填料的元素组成和矿物组成,揭示了填料去除氮磷及缓冲H⁺的作用机理.研究表明:沸石和页岩都具有较发达的中孔结构,页岩对NH₄⁺-N的吸附能力小于沸石;页岩主要组成为CaCO₃,对PO₄^3--P的去除能力大于沸石,且对水中的H⁺有较好的缓冲作用.在处理酸性淀粉废水的小试系统中,页岩中的菖蒲和芦苇,其叶片相对绿度、茎根比、平均株高等指标均好于沸石中植物.种植在页岩中的菖蒲和芦苇,其根系活力分别为沸石中植物的3.7倍和1.6倍.页岩中菖蒲,地上部分吸收氮磷总量分别是沸石中的7.8倍和3.4倍;页岩中芦苇,地上部分吸收氮磷总量分别是沸石中的3.3倍和2.2倍.由于为植物提供了pH稳定的根系微环境,页岩比沸石更适合植物生长.     

Selling “Fracking”: Energy in Depth and the Marcellus Shale

The development of horizontal hydraulic fracture drilling or “fracking” has allowed for the extraction of deep, unconventional shale gas deposits in various shale seams throughout the USA. One such shale seam, the Marcellus shale, extends through New York State, Pennsylvania, and West Virginia, where shale gas development has rapidly increased within the last decade. This has created a boom of economic activity surrounding the energy industry. However, this bounty comes with risks to environmental and public health and has led to divisive community polarization over the issue in the Marcellus shale region. In the face of potential environmental and social disruption, and a great deal of controversy surrounding “fracking” the oil and gas industry has had to undertake a myriad of public relations initiatives to legitimize their extraction efforts in the Marcellus shale region, and to frame the shale gas boom in a positive light to stakeholders. This article investigates one such public relations initiative, the Energy in Depth (EID) Northeast Marcellus Initiative. Through qualitative content analysis of EID's online web material, this article examines the ways in which the industry presents and frames natural gas development to the general public. Through appeals to patriotism, the use of environmental imagery, and a claimed commitment to scientific reason, the oil and gas industry uses EID to frame the shale gas extraction process in a positive light, all the while framing those who question or oppose the processes of shale gas extraction as irrational obstructionists.     

页岩气开发过程中存在的环境问题及对策

我国正处于页岩气开发的试验期,页岩气开发会带来水资源紧缺、水和土壤污染及甲烷泄漏等环境污染问题,因此,分析页岩气开发带来的环境问题并制定应对措施十分必要。文章详细分析了页岩气开发过程中可能引起的一系列问题,并结合我国页岩气开发实际情况提出了解决对策,希望能为我国页岩气的开发提供一定的参考。     

煤系页岩瓦斯吸附-解吸特性核磁共振实验研究

吸附态和游离态瓦斯变化规律能为煤系页岩瓦斯安全高效抽采提供技术参考,常规实验方法难以实现对吸附态和游离态瓦斯变化规律的独立表征。以阜新盆地清河门矿煤系页岩为例,采用低场核磁共振技术对煤系页岩粉试样进行瓦斯吸附-解吸实验,并提出以核磁共振T2（横向弛豫时间）谱幅值积分作为瓦斯含量定量表征指标。实验表明:吸附-解吸过程T2谱曲线有3个特性峰,对应3个横向弛豫时间截止阈值;吸附态瓦斯量与瓦斯压力符合朗格缪尔方程,而游离态瓦斯量与瓦斯压力呈线性关系;吸附态瓦斯解吸过程具有明显滞后性,且存在7.26 MPa临界滞后瓦斯压力,而游离态瓦斯吸附和解吸过程近似可逆,无明显滞后性。     

压裂返排液的超声强化臭氧氧化处理

采用超声强化臭氧氧化技术处理经絮凝、沉降脱固、过滤预处理的页岩气压裂返排液,通过实验室实验优化工艺参数,并在自行研制的超声强化臭氧氧化装置上进行了中试验证。实验结果表明,在反应时间为30min、废水pH为10、废水臭氧质量浓度为40 mg/L、超声波功率为200 W时,COD去除率可达55.2%,处理后水质可满足GB 8978—1996《污水综合排放标准》一级标准的要求。中试试验结果表明,研制的臭氧超声氧化处理装置可形成臭氧氧化、超声空化、水力空化的协同作用,处理后出水COD为90 mg/L,具有一定的推广价值。     

我国页岩气开发环境问题及对策

天然气产业发展"十二五"规划提出加快页岩气产业发展,提高天然气在一次能源消费中的比重。我国页岩气的勘探开发还处在起步阶段,部分关键技术有待突破,资源管理机制有待完善,对页岩气开发环境问题的识别与解决与世界先进水平相比还存在很大差距。介绍了我国页岩气的资源状况,对比分析了中、美的页岩气成藏特性,总结了页岩气开发各环节可能存在的水资源浪费与污染、温室气体超量散逸等环境问题,进而从政府、地方、企业3个层面提出对策与建议,为我国页岩气安全开发提供借鉴。     

中国页岩气开发环境成本计量研究及政策建议

页岩气的开发过程中会产生潜在的环境污染问题且随着页岩气开发进程的推进,环境问题会逐渐凸显,因此对页岩气开发产生的环境问题进行量化描述显得尤为重要。针对页岩气开发带来的负面和正面环境影响,如水资源耗费、地下水污染、大气污染、生态环境破坏、地质灾害和替代煤炭节约的环境效益等,结合环境成本理论分别给出各方面环境成本的量化模型;综合各项环境成本因素,建立了页岩气开发环境成本量化模型,综合分析页岩气开发对环境的影响程度;建议完善页岩气企业环境成本信息披露体系,以环境报告书方式披露环境成本信息,增加透明度以消除公众疑虑,同时建立环境污染补偿机制,最大限度减少页岩气开发带来的环境成本。     

油气田压裂返排液处理技术探讨

水力压裂是中低渗油田、非常规页岩气田增产开采的重要措施,开采会产生大量的压裂返排液,处理难度大,可能导致比较严重的水污染问题.首先基于国内外油气田压裂返排液的典型水质指标,分析了油气田压裂返排液的水质特点,包括组成复杂、多数水质指标超过国内污水回用标准、油气田压裂返排液组成差异大且处理难点不同;从处理原理、优缺点、油气田应用条件及效果出发,探讨了可用于油气田压裂返排液处理的相关技术,并提出了中国油气田压裂返排液处理存在的问题与相应的建议.