Use of Novel Water Treatment Methods for Inland Desalination of Brackish Groundwater in Qatar

Groundwater is a major water source for agriculture in Qatar. Exponential increases in groundwater withdrawal and imbalances between utilization and recharge are threatening the quantity and water quality of existing reserves. There is a need to supplement seawater and, therefore, finding ways to utilize the brackish groundwater sources is important for sustainable agricultural production systems in Qatar. The major project goal is to develop an efficient, low-cost desalination technology applicable for inland areas and small systems. Capacitive deionization (CDI) is a novel water treatment technology for dissolved salts removal, which has lower energy requirement than reverse osmosis (RO) with the potential to produce lower amounts of waste brines. CDI technology, unlike RO and nanofiltration, does not require high pressure equipment and can be operated using solar energy. We will test our novel CDI system to treat brackish groundwater and achieve various levels of salinity reduction to produce water stream for different end-use applications (e.g., irrigation of forage, food crops; livestock consumption). Initial tests will cover TDS levels up to 15000 mg/L (from 1:1, 1:2, 2:1, 2:2 electrolytes) followed by actual groundwater samples with a wide gradient in salt concentration and ionic composition. The CDI system will be tested under continuous operational mode (for ion removal & regeneration) and for its stability under various electrode charge/discharge configurations.