铁磁性颗粒辅助微波加热分解南海神狐海域天然气水合物实验研究

Experimental study on decomposition of natural gas hydrate in Shenhu area of South China Sea using ferromagnetic particle-assisted microwave heating

南海北部陆坡神狐海域是中国天然气水合物首次试采区,90%以上的水合物储存在泥质粉砂地层中。为实现天然气水合物的高效开发,必须提高泥质粉砂中天然气水合物的平均产气速率和能量效率比。笔者以泥质粉砂作为水合物合成基底,对合成的甲烷水合物开展了微波加热分解实验,研究了加入不同种类铁磁性颗粒对甲烷水合物分解的影响规律。试验结果表明,在平均产气速率和能量效率比方面,加入铁钴合金粉末的实验组表现最佳,相较空白组提高22.66%。加入纳米钡铁氧体颗粒对反应前期分解效率具有显著促进作用,纳米颗粒的小粒径和大比表面积有助于其均匀分布,优化了润湿性和表面张力,降低了“贾敏效应”。经Avrami模型分析表明,铁磁性颗粒对微波分解水合物具有良好的促进作用,其中纳米钡铁氧体效果最显著。

The Shenhu area on the northern slope of the South China Sea is the first trial extraction area for natural gas hydrate in China,with over 90%of hydrate reserves located in muddy fine sand strata.To achieve efficient development of natural gas hydrate,it is essential to improve the average gas production rate and the energy efficiency ratio in muddy fine sands.Using muddy fine sand as the base for hydrate synthesis,the authors conducted microwave heating decomposition experiments on synthesized methane hydrate,investigating the effects of adding different types of ferromagnetic particles on the decomposition of methane hydrate.The experimental results showed that the group with added iron-cobalt alloy powder performed the best in terms of average gas production rate and energy efficiency ratio,with a 22.66%improvement compared to the blank group.The addition of nano-barium ferrite particles significantly enhanced the decomposition efficiency in the early stages of the reaction.The small particle size and large specific surface area of the nanoparticles contributed to their uniform distribution,optimizing wettability and surface tension,and reducing the“Jarmin effect”.Analysis using the Avrami model indicated that ferromagnetic particles effectively promoted the microwave decomposition of hydrate,with nano-barium ferrite showing the most significant effect.