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.