Marginal Water Treatment by Combination of Two Stages of Stepped Cascade Weir and Spray Aerator

Abstract

A combination of stepped cascade weir with spray aerator systems is one of the available ecological treatments to reduce the concentration of pollutants in marginal water and to solve the problem of the water shortage for irrigation and industrial uses in Iraq. An experimental treatment system for marginal water has been constructed and installed at Al- Mustansiriya University, College of Engineering during the period from August 2013 to July 2014. The performance of the treatment schemes has been evaluated by monitoring the quality of marginal water and effluent for some parameters such as pH, Cl^-, BOD₅, COD, Fe⁺², and Mn⁺². Results indicate that the removal efficiencies for COD and BOD₅ is ranged from (43% to 51%), and (44%-52%), that the removal efficiency of ions concentrations such as Fe⁺², Mn⁺², are (30 %-48%) %, and (33% -48%), respectively, while for Cations such as Cl-, the removal efficiency is (31%-42%).

Keywords: Marginal water, spray aerator, bio-treatment, stepped cascade weir.