H. Mizuno, Y. Kansha, M. Ishizuka
Aug 20, 2014
Chemical engineering transactions
A self-heat recuperative seawater desalination process using fluidized bed evaporator with high recovery ratio (defined as product water flow rate divided by feed water flow rate) was proposed to develop a highly energy efficient desalination process. In the process, the feed seawater may cause an agglomeration derived from liquid bridge force between particles, which finally leads to defluidization. Thus, the influence of seawater feed on the fluidization was examined. Fluidizing gas velocity was changed as a parameter. The experimental results showed that the fluidizing gas velocity of more than 2.5 umf can prevent the agglomeration due to the liquid bridging. At the fluidizing gas velocity condition (u = 2.5 umf and 3.0 umf), small amount of agglomerations caused by solid bridge force was observed. However, these agglomerations did not strongly influence the fluidization and the seawater evaporation was maintained, which means that the fluidized bed can be used as an evaporator. Therefore, the novel thermal seawater desalination process using fluidized bed with high recovery ratio can be developed when the proper fluidizing gas velocity is selected.