改进型真空制冰系统的性能研究

Performance Study on Improved Vacuum Ice Slurry Making Equipment

为了降低真空制冰系统对真空度的要求,提出了在水中加入中介物质的方法,并建立了真空蒸发性能测试系统。采用浓度为26%的氨水为中介物质溶液,对真空下溶液的蒸发温度特性进行了实验研究,分析了对系统的影响。实验结果表明,在相同的初始温度和真空条件下,氨水的降温速率和降温范围明显高于蒸馏水,且在高于水的三相点压力时有冰晶形成;随着真空度的降低,氨水的降温幅度逐渐减小,但仍远大于蒸馏水,说明在相同的蒸发温度下,氨水对真空度的要求远低于蒸馏水。

To improve the vacuum degree requirement of the vacuum ice slurry making equipment,the intermediary substance was proposed to add to water.A performance test system was established to study vacuum evaporation characteristics experimentally using ammonia water with concentration of 26% as the intermediary substance solution and the influence of ammonia on ice slurry production was analyzed.The results show that the cooling rate and temperature’s drop range of ammonia water are significantly higher than distilled water with the same initial temperature and vacuum degree.Moreover,ice crystal can be formed above the pressure of water’ triple point in ammonia water.With the decrease of vacuum degree,the temperature’s decreasing scope of ammonia gradually diminishes,but still much larger than that of distilled water,which indicates that ammonia water’s requirement for the vacuum degree to achieve the same evaporation temperature is much lower.