Abstract:

Oil-based cuttings (OBCs) produced by shale gas exploitation are classified as hazardous waste. Their appropriate utilization and disposal is a key issue that urgently needs to be resolved. A single-phase microemulsion (SPM) has ultra-low interfacial tension and strong solubilization ability. In view of this, based on an analysis of the characteristics of OBCs, SPMs have been selected for their cleaning. The effects of microemulsion components and other conditions on the cleaning efficacy have been explored, as well as the deoiling mechanism and the recycling efficiency of the SPM. Our results have shown that sodium dodecylbenzene sulfonate (SDBS), n-butanol, water, and white oil in appropriate proportions can form an effective SPM. The oil content (OC) of OBCs after cleaning was reduced from 11.89% (±0.32%) to 1.13% (±0.02%) when the proportions of the aforementioned components of the SPM were 14.3%, 14.3%, 66.6%, and 4.8%, respectively. The OC of the residue further decreased to 0.28% (±0.05%) after a second cleaning with an alkaline solution. The optimum SPM conditions for cleaning OBCs were identified as a stirring speed of 200 rpm, a temperature of 30 °C, a cleaning time of 30 min, and a solid to liquid mass to volume ratio of 1:4. The main mechanism whereby the SPM cleans the OBCs is that the former reduces the combined work and adhesion work required for the removal of oil droplets from the cuttings, so that the adhesive oil is easily gathered up. Furthermore, the gathered oil phase is solubilized by the SPM.

摘要：

页岩气开采产生的油基碎屑（OBC）被归类为危险废物。它们的适当利用和处置是迫切需要解决的关键问题。单相微乳液（SPM）具有超低的界面张力和强大的增溶能力。鉴于此，基于对OBC的特征的分析，已经选择了SPM进行清洁。研究了微乳液组分和其他条件对清洁效果的影响，以及SPM的除油机理和回收效率。我们的研究结果表明，十二烷基苯磺酸钠（SDBS），Ñ-适当比例的丁醇，水和白油可形成有效的SPM。当上述SPM成分的比例分别为14.3％，14.3％，66.6％和4.8时，清洗后的OBC的油含量（OC）从11.89％（±0.32％）降低到1.13％（±0.02％）。 ％， 分别。在用碱性溶液第二次清洗后，残留物的OC进一步降低至0.28％（±0.05％）。确定了用于清洁OBC的最佳SPM条件是搅拌速度为200 rpm，温度为30°C，清洁时间为30分钟，并且固液质量体积比为1：4。SPM清洁OBC的主要机制是，前者减少了从切屑中去除油滴所需的综合工作和粘附工作，因此粘附油易于聚集。此外，