Research of the environmental impacts of brine discharges from a reverse osmosis desalination plant

The treatment of water includes many different techniques like adsorption, catalytic processes, magnetically assisted processes, membrane processes. Membrane processes are getting highly popular in recent years with their advantes like compact structure, being eco-friendly and economic, high water quality, no need another chemicals components. Purification by reverse osmosis method is quite popular and common. Desalination of seawater is a common application in the coastal areas which supply their water demands. Desalination of sea water is a solution for the problem or water shortage of expanding coastal cities which suffer from a lack of clean water supply and no public water network. However, the reproduction and growing of sea organisms are inversely affected due to the discharge of brine in the desalination plants to sea, this case affects sea life signifinatly in the region. Therefore, researches on the effects of desalination plants and discharges to sea increase in all over the world. In this study, the environmental effects of the concentrated discharge of reverse osmosis on sea water in two different tourism facilities, Bağla and Gümbet bays, in Bodrum-Muğla-Turkey. According to the analysis results; the depth average salinity increase on the diffuser was found as 0,2 and 0,2 ‰ at Bağla and Gümbet bays, respectively. The highest salinity increase at the mixing zone was found as 0,14 and 0,2 ‰ at Bağla and Gümbet bays, respectively. The salinity of the discharged reverse osmosis concentrate was 10-11 % higher than the natural sea water. In the analysis of reverse osmosis concentration, turbidity, SSM, pH, sulphate, chloride, TOC, TN values were found to be within the normal range. The reverse osmosis concentrations were very close to the natural sea water concentrations and approximately 10-15 % higher than the natural sea water concentrations. The temperature increase in the 10 m horizontal distance was less than 2 ºC. Fecal coliform was not detected in the region above the diffuser. No significant change has been detected in the depth-based pH and dissolved oxygen profiles due to the discharge.