不同钻井液体系水基钻井固废特性及土地利用价值分析

为评价不同钻井液体系水基钻井固废土地利用的可行性及资源化价值,以1个页岩气平台和2个常规气钻井单井的不同井深聚合物和磺化体系水基钻井固废为对象,系统分析其矿物组成、结构体系、理化性质和污染特性,并运用能值理论,系统、定量地衡量水基钻井固废土地利用价值。结果显示:各井段聚合物和磺化体系水基钻井固废含有大量成土元素和矿物,且质地属于砂质壤土或壤质黏土,结构及养分基础良好；水基钻井固废的浸出液COD值和石油烃含量等污染物指标超过相关标准,但均可通过降解去除；能值价值分析显示土地化利用方式相比于制备烧结砖方式,生产效率高,对于社会和环境资源依赖性低,对环境产生的压力小,可持续发展潜力大。研究表明,页岩气和常规气田不同体系的水基钻井固废土地利用可行,在能值价值方面,土地利用方式的资源化价值优于制备烧结砖方式。 

Analysis of the different water-based drilling fluid system solid waste characteristic and the value of land use

In order to evaluate the feasibility and resource value of the different water-based drilling fluid system solid waste (WDSW) land application, this paper analyzes systematically the mineral composition, structural system, physical and chemical properties and pollution characteristics of WDSW of polymer and sulfonating drilling fluid systems at different well depths in one shale gas and two conventional gas drilling platforms. And the value of WDSW land use was measured systematically and quantitatively by the energy theory. The results show that the WDSW of polymer and sulfonating drilling fluid systems has been found with lots of soil elements and minerals, and the texture belongs to the sandy loam or clay soil so as to form a well-mixed minerals, good nutrient and structure foundation of WDSW. Furthermore, the COD and petroleum hydrocarbons content rate of the lixivium of WDSW turn out to be over the maximum allowable content rate of the relevant environmental quality standard of the given soil, which could still be removed by degradation. Emergy analysis shows that compared with the method of preparing sintering bricks, the land-use method has high production efficiency, low dependence on social and environmental resources, less pressure on the environment, and great potential for sustainable development. In the end, on the basis of the comprehensive characteristic and emergy analysis, the land use of WDSW of polymer and sulfonating drilling fluid systems at different well depths in shale gas and conventional gas drilling platforms is feasible, and the land use method is superior to the way of preparing sintering bricks in terms of energy value.