Investigation of Karoon River Self-Refinement Capacity Exposed to Khorramshahr‘s Soup Factory Based on EC, BOD, COD and DO Parameters Using River Sediments

Khorramshahr’s soup factory daily producing 1000 tons of soup chips and 14 tons of glycerin as well as other kinds of soup is situated near Karoon River which discharges 144000 m3 wastewater in to this river annually. The aim of this research is to study the effect of the wastewater on river water quality and the capacity of its self-refinement. For this purpose, the samples were taken from river sediments and outlet wastewater in 10 months ( from September 2006 to July 2007) in the 3 stations include 50 meters far from upstream as control (×0) , 50 and 500 meters from downstream (×1 and ×2) where the wastewater is discharged. In this study, the physico- chemical parameters of both water and wastewater from the factory such as temperature ,BOD,COD,DO as well as their properties such as bicarbonate, sulfate, calcium, magnesium, sodium, potassium, organic matter percentage and percentage of particle size were investigated. The statistical analysis showed that in the second station the BOD and COD increased 31%, 57% relatively compared to control station that was an indication of wastewater contamination. In the third station, these parameters decreased 42%, 47% compared to second one, suggesting that the river refines itself through oxygen-taking over route and contaminants’ adsorption by bed sediments in different ways such as electrostatic and proton- taking mechanism and hydrogen bond through water bridge. These differences were significant at level 5% of the Dunned test.