超声波作用下天然气水合物的形成

The Formation of Natural Gas Hydrates with Ultrasonic

实验搭建了一套高压条件下超声波作用于天然气水合物反应的装置系统,该系统中超声波的频率为20kHz,功率为0～150W可调.利用该装置研究了超声波对天然气水合物生成过程和引导时间的影响.实验发现声场中生成特征曲线诸如温度、压力、流量等随着时间的推迟与静态反应时不同,反应引导时间约缩短至静态时的1/6,分解后重新反应引导时间甚至缩短至静态的1/10.水合物成核速率提高是由于超声波提高了传质系数、成核点浓度和过饱和度,而降低了界面能.

The effect of ultrasonic on the formation of natural gas hydrates was investigated, including the characteristic curve of formation, induction time. The experiments were performed in a high-pressure experimental system with ultrasonic （20kHz, 0 - 150W）. The experimental results indicate that the characteristic curves of temperature, pressure and flow-time are different with those of the static. And the induction time with ultrasonic was about 1/6 of that of the static and only about 1/10 if rehydration after decomposition. The increase of the nucleation rate should appeal to the increases of the mass transfer coefficient, the concentration of nucleation-active particles, supersaturation and the decrease of surface energy with ultrasonic.