Abstract: Gas hydrates represent a promising technology for gas storage and transportation. However, their practical application is constrained by the slow formation kinetics of hydrate formation. "Active ice"—synthesized by uniformly dispersing hydrate kinetic promoters into ice powder—has been demonstrated to significantly accelerate gas hydrate formation, thereby offering an effective solution to the kinetic bottleneck in hydrate-based gas storage and transportation. In order to investigate the hydrate formation kinetics of active ice under large-scale application conditions, this study prepared active ice using natural snow as the raw material and employed it in kg-scale hydrate formation experiments. The effects of the concentration of kinetic promoters, reaction pressure, active ice temperature, and packing density on methane hydrate formation kinetics were examined. Additionally, the recycling performance of the active ice were evaluated. The results indicated that active ice derived from natural snow effectively promoted methane hydrate formation. Specifically, when the concentration of the kinetic promoter (sodium dodecyl sulfate, SDS) exceeded 0.25wt%, and the active ice temperature was maintained above 269.15 K, methane hydrate formation was nearly completed within 6 min, achieving a maximum methane uptake of 177.00. The methane uptake increased slightly with rising reaction pressure. Furthermore, by adjusting the packing density of the active ice bed, a maximum apparent gas storage density of 118.90 was attained. In kg-scale hydrate formation and dissociation experiments, the active ice exhibited excellent cycling performance. Collectively, the results of the kg-scale hydrate formation suggested that active ice does not induce significant scale-up effects during hydrate formation, and has essentially met the performance requirements for practical application in hydrate-based gas storage and transportation.

Key words: gas hydrate, gas storage and transportation, active ice, scale-up, snow

摘要： 通过向冰粉末中均匀分散水合物动力学促进剂制备得到的“活性冰”可以显著加速气体水合物的生成，从而有效解决水合物法气体储运的动力学问题。为了研究活性冰大规模应用时的水合物生成动力学特性，本工作以天然雪为原料制备活性冰，并将其应用于千克级水合物生成。采用恒压法考察了动力学促进剂浓度、反应压力、活性冰温度及堆积密度对甲烷水合物生成动力学的影响，同时对活性冰的循环使用性能展开研究。结果表明，以雪为原材料制备的活性冰能够有效促进水合物的生成；动力学促进剂十二烷基硫酸钠(SDS)浓度大于0.25wt%，且活性冰温度在269.15 K以上时，水合物生成反应可在6 min内基本完成，且最高储气量可达177.00；甲烷储气量随压力的升高而略微增大。此外，通过改变活性冰的堆积密度，最高可取得118.90的表观储气密度。在千克级的水合物生成-分解循环过程中，活性冰也表现出良好的循环性能。上述千克级水合物生成结果表明，活性冰用于水合物生成时无明显的放大效应，已基本满足水合物法气体储运技术的应用需求。

关键词: 气体水合物, 气体储运, 活性冰, 规模放大, 雪