Forward Osmosis Desalination: Potential Application For Irrigation In Qatar

Abstract

Qatar, with its low rainfall and limited natural water resources, is heavily reliant on desalinated water to meet the needs of its rapidly growing population. The agricultural sector alone uses 50% to 60% of ground water (GW) as its water source, where extraction rates are several times the natural GW recharge rate. Present desalination technology employed in Qatar is energy inefficient and uneconomical to replace GW sources for irrigation. This paper discusses the benefits of Forward Osmosis (FO) desalination technology as an alternative to existing desalination technology. FO can reduce current desalination cost by more than 30% to produce clean water for irrigation in Qatar. FO has the potential to increase the availability of freshwater both in coastal areas with limited resources and in areas where seawater, salinized groundwater and treated wastewater are available. This paper reviews different FO hybrid desalination methods which have potential to produce clean water for irrigation and presents also data from both 1) a pilot plant of a FO+Reverse Osmosis (RO) process that has been developed by the Centre for Osmosis Research and Applications (CORA) at the University of Surrey and 2) a commercial plant by Modern Water plc (MW) in Oman. Furthermore, the paper presents a novel concept of an integrated FO desalination process using an aqueous Dimethyl Ether (DME) solution as draw agent with thermal regeneration. The simulation results have shown the efficiency of the FO process in comparison with conventional desalination processes in terms of specific energy consumption (SEC) and clean water production performance.