LOW QUALITY WATER TREATMENT AND DESELIMATION ABASED ON SOLAR ENERGY TECHNOLOGIES

The present study introduces an application of solar energy in water treatment and desalination for small-scale needs. A lab scale solar system is used for brackish water and agricultural drainage water treatment and desalination. agricultural drainage water passes through sand filter to solar collector, then the heated water enters to evaporating chamber maintained at low pressure. Once the hot water enters to this chamber it is evaporated and condensed to fresh water. The effect of different factors such as solar radiation, vacuum pressure, cooling water flow rate and inlet water temperature which affect on system productivity was studied. An economic analysis was conducted to estimate the cost of water production by the proposed system. The system was efficient to reduce total dissolved solid (TDS) from 1500-2400 mg/lit to less than 15 mg/lit and to reduce the Chemical Oxygen Demand (COD) from 50- 90mg/lit to less than 5 mg/lit. The proposed system gives a reasonable production of fresh water up to 5 L/m2/day. The system achieved gained output ratio (GOR) 1.2 and distillation efficiency about 52%.