Evaluating the Performance of Membranes Type Koch in Hartha Power Plant in Iraq

The performance of the reverse osmosis membranes used in the water desalination unit at the Hartha Power Plant, one of the electrical power plants in southern Iraq, for the period of 2009 to 2010 is evaluated in this article. The membranes are of the type (TFC-Koch) model (8822XR-365). This unit has a capacity of 100 m3/h withdraws water from Shat Al-Arab River as a raw water having Total Dissolved Solid (TDS) > 3000 ppm, and consists of two stages with total recovery and salt rejection of about 60% and 95%, respectively. Now, the water salinity of raw water to the power plant is more than 10,000ppm. Based on a review of the chemical analysis of various ions present in water for both permeate and rejected streams from the unit log book, the efficiency of the Reverse Osmosis (RO) membranes is based, and only those readings where the overall recovery was 60% were selected. The findings showed that the reduction of membrane efficiency is attributed to the membrane blockage due to scaling and fouling. Under high fouling circumstances, the permeate flow rate is lowered, requiring a high feed pressure to produce the design permeate flow rate or percent recovery. The behavior of RO membranes was simulated using conventional Saehane software and compared to a predicted model established by the same authors. The results showed that the reduction in water flow in elements one and two in each vessel in the first array is due to the high permeate water flux through these two elements beyond the operation limitations. As a result, these two elements must be replaced or shifted in relation to other elements on a routine basis.