摘要
海水中的盐离子成分阻碍水合物成核进程,使得水合物法海洋碳封存耗时长、封存比率低。结合水合物非均相成核特征考虑,认为在局部区域内实现水合物优先成核,进而带动大片海域内水合物扩展生成的封存方法极具工业可行性。因而,开展海水水合物强化生成方法基础研究是推进水合物法海洋碳封存应用落地的基础。基于此,以高效、高转化率生成水合物为目标,在实验室尺度分别探究了高过冷度、添加剂四丁基溴化铵(TBAB)以及变温速率对海水水合物生成特性的影响。结果表明,受到盐离子抑制作用,400 m深度海水中水合物自然生成难度极大,而提高生成过程的过冷度可增强水合物生成驱动力;热力学添加剂TBAB难以显著改善海水水合物的生成条件,但可使生成速率有所提高;0.3 K/min降温速率下的水合物转化率分别是过冷度作用和添加剂作用下的1.28倍和1.19倍。在后续研究中,应考虑多种强化生成方法的耦合作用效果,开发更能缓解海水水合物生成难题的技术手段。
The salt ion components in seawater hinder the hydrate nucleation process,making the hydrate method for marine carbon sequestration take a long time and have a low sequestration rate.Considering the non-homogeneous nucleation characteristics of hydrates,it is feasible to implement a storage method that achieves preferential hydrate nucleation in local areas,leading to the extended generation of hydrates across large sea areas.Therefore,fundamental research on the enhanced generation of seawater hydrate is essential for promoting the application of the hydrate method for ocean carbon sequestration.Based on this premise,laboratory-scale investigations were conducted to study the effects of high subcooling,additives(TBAB),and variable temperature rates on the seawater hydrate generation characteristics,aiming for efficient and high conversion rate hydrate generation.The results indicated that the natural generation of hydrates in seawater at a depth of 400 m is extremely difficult due to the inhibitory effects of salt ions.However,increasing the supercooling degree of the generation process can enhance the driving force for hydrate formation.Although the thermodynamic additive TBAB did not significantly improve the conditions for seawater hydrate generation in the present experiments,it did increase the rate of generation.Furthermore,the study found that the hydrate conversion rate at a cooling rate of 0.3 K/min was enhanced by 1.28 and 1.19 times compared to the effects of subcooling degree and additives,respectively.In conclusion,future studies should consider the coupling effects of various enhanced generation methods to develop technical means that can better mitigate the challenges of seawater hydrate generation.
作者
杨明军
宋维
张磊
凌铮
陈兵兵
宋永臣
YANG Mingjun;SONG Wei;ZHANG Lei;LING Zheng;CHEN Bingbing;SONG Yongchen(School of Energy and Power Engineering,Dalian University of Technology,Dalian 116081,Liaoning,China)
出处
《化工学报》
EI
CSCD
北大核心
2024年第8期2939-2948,共10页
CIESC Journal
基金
国家自然科学基金青年科学基金项目(52206076)
大连市科技创新基金项目(2023JJ11CG010)。
关键词
二氧化碳
水合物
成核
相平衡
carbon dioxide
hydrate
nucleation
phase equilibria
