Performance evaluation of humidification-compression desalination

The performance of humidification-dehumidification desalination, in which dehumidification is carried out by compression, was studied experimentally. A test rig was designed and assembled based on a new idea. In this system, the carrier gas is humidified through direct contact with hot water; and after humidification, the humid air is compressed by a compressor and cooled in a heat exchanger to recover the humidity as desalinated water. The effects of water-to-air ratio, water and air inlet temperatures, operating pressure, and condenser temperature on desalination performance were examined. It was found that the increase in temperature of the feed water and/or inlet air to the humidifier increased the water production rate and gain output ratio (GOR) of the system. The water-to-air ratio showed an increasing-decreasing trend in relation to the water production rate and GOR of the system; the best water-to-air ratio was found to be 2.