REUSE OF TREATED SANITARY SEWAGE IN NAJAF CITY FOR AGRICULTURAL PURPOSES

Abstract

Sanitary sewage treatment plants can be considered as a source for water that can be used for different purposes. The agricultural sector is a steady and very big potential consumer of reclaimed water . so , treated sewage reusing in agricultural purpose is a good goal where it requires simpler treatment in comparison with other purposes In this study , the quality of treated sewage in Najaf sewage treatment plant have been evaluated and compared with standard specifications of America, Egypt and Iraq water quality that used for agricultural purposes. The evaluation process includes samples collection from effluent of treatment plant for a period of (12) months from January 2009 to January 2010. Then measuring the quality of treated sewage which includes measurement of Biochemical Oxygen Demand (BOD), Suspended Solid (S.S) ,Total Dissolved Solid (TDS), and PH .Also concentration of chemical elements which may cause harmful effect on plants like Cl, Based on the results of this study it was found that: (1) Biochemical Oxygen Demand, Suspended solid , Total Dissolved Solid and PH values of effluent treated sewage of all date of measurement are within the maximum allowable range according to the Egyptian Standards and American Standards. (2) the concentrations of values of chlorine (Cl),sulphate (SO4), Phosphate (PO4), Sodium (Na) and Calcium(Ca) are :83%, 75%, 100%, 75%, 92% respectively are less than the Egyptian allowable rang while 75% of magnesium (Mg) values are exceeding the allowable limit. (3) TDS, PH, PO4, NO3 and Ca values of effluent treated sewage of all data of measurement are within the Iraqi allowable range. (4) The concentration values of BOD, S.S, Na and Mg are 58%, 75%, 75% and 1% respectively are less than the Iraqi allowable range. (5) no sodicity problem in the soil as a result of the use of treated water effluent from Najaf sewage treatment plant.