deoxygenation andreaeration coupled hybridmixing cells based pollutant transport model to assess water quality status of a river

prediction of spatial and temporal variation of water quality is vital for managing pollutantsdisposal into the rivers. depletion of dissolved oxygen (do) takes place due to the consumption of oxygen bymicrobes to digest bio-degradable pollutants which enter a water course. reaeration takes place in a specificrate depending on do deficit. many investigators have formulated models as an alternative to the fickianmodel for the advection dispersion pollutant transport. since streeter-phelps research on bod-do modeling,many researchers have studied fate of pollutant considering first order reaction along with only advection. thestreeter-phelps dispersion model includes deoxygenation and reaeration along with advection and dispersionand which has been solved by defining an axillary variable relating do deficit and bod concentration. thusthis paper considered first order decay and reaeration along with advection and dispersion to simulate spatialand temporal variation of do concentration using a hybrid mixing cells model. the proposed model has beensuccessfully applied for a hypothetical flow conditions and the river brahmani, india. river flow requirementand regulation for pollutant disposal with pre-treatment were optimized using the responses of proposedmodel for this river. this research analyzed the selected river reach using proposed model having a particularflow and channel characteristics and found that release of 1180m3/s from rengali dam is required to avoidpollution problem. however, in absence of this flow at least 50% of pretreatment pollutants are requiredbefore released into river tikira.