EAGER: Effects of Thermodynamic Phase Changes at Reservoir Conditions on the Interfacial Properties of Chemicals Used in Hydraulic Fracturing

水力压裂和水平钻井的结合极大地影响了美国的能源生产，并有望在世界其他地区产生类似的影响。从以前不经济的页岩气储层增加天然气产量已经导致天然气价格上涨，几个州的经济繁荣，以及对新制造设施的巨大投资。潜力如此之大，以至于已经有人在讨论美国实现能源独立甚至成为能源净出口国的可能性。然而，水力压裂作业的增长导致了对环境影响的担忧。可能引起最大关注的一个潜在影响是水力压裂液中使用的化学物质对地下水的污染。在过去的四十年里，广泛的命运和运输研究为理解和预测典型的压裂流体化学品的迁移提供了深入的资源，如果它们到达地下水含水层，但是典型的页岩气储层的条件与含水层中的条件有很大的不同。该EAGER项目源于以下假设：作为水力压裂中的载液的水溶液中的热力学相变将导致页岩气矿物和用作支撑剂的砂对压裂液化学品的吸附大大增加。这种增加的吸附意味着大大降低了化学品找到任何可能迁移到地下水含水层的途径的可能性。理解这些潜在的相变是更加困难的高浓度的溶解盐（总溶解固体，TDS）在水力压裂作业中发现？回流？水研究人员提出实验来研究压裂液注入页岩气储层时产生的高温和电解质浓度引起的相变。他们还将在气藏温度、压力和TDS条件下测量岩石/盐水和支撑剂/盐水界面处压裂化学品的界面特性。实验将包括分批和流通反应器和测量。 该建议的智力价值来自于对更好地理解储层条件对储层中压裂液化学品的热力学活性的影响的贡献。这些结果将为理解水力压裂作业以地下水化学污染的形式产生长期环境损害的真正潜力提供另一个关键因素。该提案的更广泛影响来自研究生和本科生的教育利益，他们将在进行提案中描述的实验时得到支持。研究结果也将对关于水力压裂法的辩论做出重大贡献？地下水污染的可能性。 研究人员还预计，这些结果将导致对更好的压裂化学品设计的讨论，以提高页岩气储层中极端条件下压裂液的性能。

1252249HarwellThe combination of hydraulic fracturing and horizontal drilling has dramatically affected energy production in the United States and is poised to have a similar impact across the rest of the world. Increased natural gas production from previously uneconomical shale gas reservoir has already led to plummeting natural gas prices, economic booms in several states, and dramatic investments in new manufacturing facilities. The potential is so large that there is already discussion of the possibility of the US becoming energy independent and even becoming a net energy exporter. The growth in hydraulic fracturing operations has, however, led to fears of environmental impacts. One potential impact which causes perhaps the most concern is ground water contamination by the chemicals used in the fracking fluid. Extensive fate and transport studies over the past four decades provide a deep resource for understanding and predicting the migration of typical fracking fluid chemicals should they reach ground water aquifers, but conditions in a typical shale gas reservoir differ dramatically from those in an aquifer. This EAGER project stems from the hypothesis that thermodynamic phase changes in the aqueous solutions which are the carrier fluids in hydraulic fracturing will lead to greatly increased adsorption of fracturing fluid chemicals by both the shale gas minerals and the sand used as a proppant. This increased adsorption implies a greatly reduced potential for the chemicals to find any kind of path by which they might migrate to a ground water aquifer. Understanding these potential phase changes is made more difficult by the high concentrations of dissolved salts (total dissolved solids, TDS) found in hydraulic fracturing operation ?flowback? water. The investigators propose experiments to study the phase changes induced in fracturing fluids by the high temperatures and electrolyte concentrations that develop when the fluids are injected into a shale gas reservoir. They will also measure the interfacial properties of fracking chemicals at the rock/brine and proppant/brine interfaces at gas reservoir conditions of temperature, pressure and TDS. Experiments will include both batch and flow-through reactors and measurements. The intellectual merit of the proposal arises from the contribution to better understanding the effect of reservoir conditions on the thermodynamic activity of fracturing fluid chemicals in a reservoir. The results will provide another key element in understanding the true potential of hydraulic fracturing operations to produce long term environmental damage in the form of chemical contamination of ground water. The broader impact of the proposal arises from the educational benefits to the graduate and undergraduate students who will be supported while conducting the experiments described in the proposal. The results will also make a significant contribution to the debate about fracking?s potential for ground water contamination. The investigators also expect the results to lead to a discussion of design of better fracking chemicals to improve the performance of the fracking fluids under the extreme conditions found in gas shale reservoirs.