Multi Stage Flashing Desalination with Direct Mixing Condensation

Abstract

Multi Stage Flash desalination technology has been a leading technology in the desalination market for the last four decades. However as a result of the continuous increase of costs for the special materials required for the tube bundles the share of MSF technology in the market is nowadays steadily shrinking. Aim of the present work is to present a novel configuration for the MSF process. In the proposed arrangement evaporation occurs in a multi stage vertical column filled with packing material to enhance the achievement of flashing equilibrium in each stage, while condensation occurs in a second column through direct mixing with a colder water stream. Thermal integration for the recovery of condensation latent heat is performed by an external plate-and-frame heat exchanger, which reduces dramatically the quantity of special materials required at the same time significantly enhancing the heat transfer. A preliminary analysis of feasibility and potentials of such process is presented.