HCFC141b乳液及微乳液体系水合物生成过程实验研究

Experimental Study on Hydrate Formation Process from HCFC141b Emulsion and HCFC141b Micro-Emulsion

为促进制冷剂快速生成水合物,首先利用高剪切混合乳化机制备HCFC141b乳液来增大两相界面,考察了剪切乳化时间、环境浴温度、HCFC141b浓度、"记忆效应"和高浓度表面活性剂对HCFC141b乳液水合反应过程的诱导时间和过冷度的影响.以此为基础,由T20/卵磷脂复配表面活性剂和T80研制热力学稳定的HCFC141b微乳液来提高两相相容性,揭示了HCFC141b微乳液水合反应过程中的晶体生长特征.微乳液中HCFC141水合物晶体均匀快速生长,与乳液水合反应相比,其诱导时间和过冷度大大减小.该研究为有效促进水合物结晶开辟了新途径.

The way by increasing the interface and compatibility between refrigerant and water to promote the rapid formation and growth of refrigerant hydrate is investigated. HCFC141b emulsion was prepared by high-pressure cutting method to increases the interface. The influencing factors, including emulsification time, bath temperature, HCFC141b content＇memory effect＇ and high-concentration surfactants, on induction time and supercooling degree of HCFC141b hydration are studied. Then, the thermodynamically stable HCFC141b micro-emulsion is successfully prepared with aid of T20/lecithin compound surfactants and T80 single surfactant to increase the compatibility of refrigerant and water. The characteristics of hydrate formation of HCFC141b micro-emulsion were revealed. The results have shown that low bath temperature, optimum HCFC141b mass concentration as well as long emulsification time are conducive to hydrate formation form HCFC141b emulsion; the ＇memory effect＇ has an important role in the promotion of hydration but does not accumulate; the surfactants T20, T80, SDS, SDBS and soybean lecithin have different influencing degrees on the promotion of hydration and there exists an idea concentration of each surfactant; HCFC141b can form hydrate rapidly and uniformly in the micro-emulsion. Compared with that of hydrate formed form HCFC141b emulsion, the induction time and supercooling degree of hydration form HCFC141b micro-emulsion are greatly reduced, which indicates that increasing the compatibility of refrigerant and water by preparation of micro-emulsion is a new way to promote refrigerant hydrate crystallization.