Theoretical and experimental investigation of moderate salinity water treatment

The rapid increase in the world population and the unsustainable production (industrial and agricultural), consumption and living activities of this population caused a coniserable pollution in the existing water resources which poses a threat to living and environmental health, has caused the loss of water resources. According to World Bank data, countries have to quadruple their spending to US$150 billion annually to provide universally safe water and sanitation, and the high cost of clean water means countries have access to safe and affordable sanitation for all by 2030, according to the United Nations' Sustainable Development Goal. It is known that there are problems in Kirkuk, Iraq, due to the contamination of water resources with inorganic and organic pollutants. Considering that water pollution causes diseases such as cancer, neurological disorders, cardiovascular diseases, respiratory, circulatory and digestive system diseases, it is of primary importance to keep our water resources clean and to clean our dirty water resources in an eco-efficient way and make them usable. Hence, in this study the Zab River in the city of Kirkuk was used as the water source. This study was carried out for to develop a treatment system to be used in the water treatment process in a drinking water treatment plant in the region where the Zab River is used as a water source in the city of Kirkuk and for to evaluate the performance of this developed system. Samples were taken from the raw river water during the filtration stages and after the water reached the end user. In order to evaluate the performance of the facility, physical, chemical and biological tests were carried out on the water samples taken and it was determined whether the water obtained after filtration complies with the criteria that standard drinking water should provide. The water temperature of water samples obtained from the investigated station was 24.8-27.8oC; electrical conductivity ranged between 54.2-747.8 µS.cm-1, turbidity rate ranged between 0.0-0.04 NTU, total dissolved solids concentration ranged between 27.1-373.5 mg.L-1, pH value ranged between 6.4-10.4. It was observed that the total water hardness ranged from 10.4 to 21.0-89.5 mg.L-1. In the samples examined, the chloride ion concentration ranged between 18.0-44.3 mg.L-1, the sulfate concentration ranged between 1.6-26.2 mg.L-1, the sodium concentration ranged between 4.70-37.2 mg.L-1, the potassium concentration ranged between 0.20-1.20 mg.L-1, calcium concentration ranged between 14.1-63.3 mg.L-1 and NaCl concentration ranged between 0.1-0.8 mg.L-1. It was determined that these values do not pose a risk. E. coli counts were made in the biological tests performed on the examined samples and the total number of bacteria was determined. However, it was determined that the results obtained were outside the guidelines of the World Health Organization. It was determined that the applied filtration process had less effect on the physical properties (temperature and turbidity) of the water samples, but provided more significant improvement in terms of total dissolved solids, NaCl, electrical conductivity, pH, total hardness, sodium, potassium, calcium and chloride ions concentrations.