环戊烷水合物作为氨基酸型促进剂初筛方法的实验研究

Experimental Study on Primary Screening Method of Amino Acid Type Promoter Using Cyclopentane Hydrates

固态天然气水合物是一种潜力巨大、高效安全的储能方式,却一直受限于其苛刻的生成条件和缓慢的生成速率,因而近年来水合物促进剂成为人们关注的焦点。为此,通过对比测试了正缬氨酸、丙氨酸和组氨酸在常压环戊烷水合物体系和高压甲烷水合物体系中的效果,研究利用更为安全的环戊烷体系对水合物促进剂进行初筛的可行性。结果表明:同丙氨酸和组氨酸相比,环戊烷体系中正缬氨酸具有最高效的促进效果,显著提升了水合物生成速率,其最适浓度(质量分数)为0.5%,诱导时间和反应最高温度分别为9.5 min和4.5℃。另外,乳化剂Span 20对正缬氨酸有良好的协同增效作用;同时,正缬氨酸在甲烷水合物体系同样具有最佳的促进性能,有效提升了甲烷水合物的储气量,初始过冷度的增加可有效提高水合物生成速率与储气能力。因此,环戊烷水合物体系可以作为一种初步筛选高效氨基酸型促进剂的方法。

Solid natural gas hydrate is a kind of energy storage method with high efficiency and safety.However,it is limited by harsh generation conditions and slow generation rate.Therefore,hydrate promoters become the focus of attention in recent years.The effect of norvaline,alanine and histidine in the normal pressure cyclopentane hydrate system and the high pressure methane hydrate system were compared and tested,and the feasibility of using safer cyclopentane system to screen hydrate accelerators was studied.The results show that compared with alanine and histidine,norvaline in the cyclopentane system has the most efficient promotion effect,which significantly increases the rate of the hydrate formation with the optimal concentration(mass fraction)of 0.5%.The induction time and the maximum reaction temperature is 9.5 min and 4.5℃,respectively.In addition,the emulsifier Span 20 has a good synergistic effect on the norvaline.Similarly,norvaline also has the best promotion performance in the methane hydrate system,effectively enhancing the gas storage capacity of the methane hydrate.It is found that high initial subcooling leads to fast hydrate formation rate and large gas storage capacity.Therefore,the cyclopentane hydrate system can be used as a preliminary screening method for high-efficiency amino acid promoters.