小型气体水合物蓄冷装置的实验研究

Experimental Research on Performance of Small Scale Cool Storage Apparatus with Gas Hydrate

采用一种内置换热、外置促晶式小型气体水合物蓄冷装置,以HCFC-141b气体水合物为蓄冷工质,测试和计算了气体水合物蓄冷过程中蓄冷量、生长速率、水合率以及总体换热系数等特性参数值,详细考察了换热器种类、十二水合硫酸钠(SDS)的含量、各种促晶方式(连续促晶、促晶5min以及融冰快速成核)等因素对以上特性参数的影响.实验结果表明:采用带垂直金属翅片的换热器相对于采用光管换热器,可以大大提升蓄冷性能,而且在此基础上,通过添加质量分数为0.04%的SDS,可以进一步提升性能.对于3种促晶方式的研究结果表明:连续促晶具有最好的蓄冷效果,但会额外增加能耗并诱发装置故障;融冰快速成核的蓄冷效果最差,但不需要促晶泵,值得进一步深入研究;促晶5 min的蓄冷效果处于中间状态,是目前最具有应用价值的一种促晶方式.

HCFC-141b hydrate was adopted as the cool storage medium in a small scale cool storage apparatus. Some parameters in the process of cool storage were tested and calculated including cool storage amount, growth velocity, hydrate packed factor（HPF） and general heat transfer coefficient. The effect of different heat exchangers, sodium dodecyl sulfate（SDS） concentration, and crystallization enhancement methods on these characteristic parameters were examined. The experiment results indicate that compared with using the bare pipe heat exchanger, using the heat exchanger with vertical metal fins can improve cool storage performance greatly, and adding SDS with concentration of 0.04% can further improve cool storage performance. The continuous crystallization enhancement has the best cool storage effect in the three crystallization enhancement methods but it will cause extra power consumption and apparatus malfunction. The cool storage effect with the fast nucleation from melting ice is the worst but crystallization enhancement pumps are not needed. It appears that the crystallization enhancement for five minutes has the greatest application potential currently.