Permeability in the presence of gas hydrates

利用以水合物形式锁定的甲烷气体可能会使世界能源储量翻一番，同时产生的有害排放比传统能源更少。气体水合物是一种固体晶体化合物，将气体分子包裹在氢键水分子的晶格中。尽管水合物看起来类似于冰，但当它们暴露在大气条件下时，每一体积的水合物将释放超过160体积的甲烷气体。加拿大北极生产测试的初步迹象表明，相当数量的天然气可以从水合物中生产出来。加拿大是第三大天然气出口国，随着国内需求的增加，我们有机会利用我们惊人的水合物储藏天然气资源(约500万亿立方米)来增加我们的常规储量(约11万亿立方米)。这个创新的项目研究相对未开发的天然气水合物-沉积物混合物领域，特别是这个独特系统中的流体流动。这项研究的目的是描述和评估渗透率对水合物储集层产气量的影响。渗透率很重要，因为水合物储集层的产气率是水合物带渗透率的强烈函数；然而，目前的模型和测量表明，对于相同的水合物饱和度，预测的渗透率有七个数量级的变化。我们小组正在通过一个实验和理论研究相结合的综合计划来研究这一重要参数的特征，该计划将微观、中观和宏观层面联系起来，以充分了解渗透率对水合物储集层生产天然气的影响。我们采用了多层次协作的方法来解决一块水合物回收之谜，这无疑将有助于从水合物中生产甲烷气体，从而不仅造福于能源行业，也造福于普通民众。

Tapping into the methane gas locked in hydrate form could potentially double the world's energy reserves,while producing less harmful emissions than conventional energy sources. Gas hydrates are solid crystallinecompounds that encage gas molecules inside the lattices of hydrogen bonded water molecules. Althoughhydrates appear similar to ice, they will release over 160 volumes of methane gas for each volume of hydratewhen exposed to atmospheric conditions. Early indications from production tests in the Canadian Arctic showthat a significant amount of gas can be viably produced from hydrates. Canada is the third largest exporter ofnatural gas and, along with increasing domestic demands, has the opportunity to augment our conventionalreserves (~11 trillion cubic meters) with our staggering resources of gas from hydrate reservoirs (~500 trillioncubic meters).This innovative program investigates the relatively unexplored field of gas hydrate-sediment mixtures,specifically the flow of fluids within this unique system. The objective of the proposed research is tocharacterize and assess the effect of permeability on gas production from hydrate reservoirs. Permeability isimportant in that gas production rates from hydrate reservoirs is a strong function of permeability of the hydratezone; however, current models and measurements suggest a variation of seven orders of magnitude of predictedpermeability for the same hydrate saturation. Our group is approaching the characterization of this importantparameter through an integrated program of experimental and theoretical research, which links micro, meso,and macro level scales to garner a full understanding of the effects of permeability on the production of naturalgas from hydrate reservoirs. We have adopted a multilevel collaborative approach to solving one piece of thehydrate recover puzzle which will no doubt contribute to the production of methane gas from hydrates and thusbenefit not only the energy industry but also the general population.