ABSTRACT
With the aid of cold energy from regasification of liquefied natural gas (LNG), freeze desalination (FD) is an emerging technology for seawater desalination because of its low energy characteristics and insensitivities to fouling problems. This chapter investigates the major operating parameters of FD and its hybridization with membrane distillation (MD). It was found that the optimal freezing duration per batch was 1 h for an iron crystallizer. The optimal coolant temperature should be around −8 °C. To ensure the purity of the product ice, the raw ice should be washed by about one-half of the MD distillate. To treat 1 kg seawater by FD, the cold energy could be provided by the regasification process of 1.26 kg LNG. The concentrated FD brine was further treated by vacuum membrane distillation to increase the total water recovery. The heating duty could be covered by either solar panels of 13.8 m2 or the regasification of 3.10 kg LNG. The total water recovery was 74% in one-hour treatment of 1 kg saline water.
