The purpose of this research is based on Zayandehroud River water quality modeling of dissolved oxygen in the water. Dissolved oxygen modeling Ctechnique has been used. Given that this study is focusing on industrial effluents Therefore, the division of the river, in order to take samples of river water, in the range of Isfahan Steel Factory, Steel Plant Mobarake andthe places created from industrial effluents entering the river above have been carried out. Sampling of Zayandehroud River, given that the river is narrow and shallow, and there is the possibility of harvesting manually sampled monthly in themonths of December, January, February, March and April was performed. Every month, 10 samples from the river (in the range stated) were obtained. DO measurements were performed with a portable 8403 models. It is driven by parameters such as adsorption, surface roughness and turbulent river, the coefficients estimated by the Winkler method idifferent from the actual value of parameters, so the Winkler method for dissolved oxygen measurement is not used. River water quality model based on DO modeling was performed. The simulation of DO was done in two different ways using the CSP model. The first method only considered the CBOD concentration (BOD5). The second method is considered synchronous NBOD quantities and CBOD (overall BOD). Finally, the model parameters including the K a , k d , k c are obtained by regression. To determine k a of experimental methods that are based on the rate and depth were performed. To determine the parameters k d , k c Long-term BOD analysis is used. Key Words: Biochemichal Oxygen Demand, Dissolved Oxygen, CSP, Zayanderood River
