Design criteria for presedimentation basin treats : shatt al-Arab river water

Abstract EN

The design of presedimentation basins is based on design criteria including surface overflow rate and detention time.

The previous studies differ in specifying the criteria values, and, subsequently, it is difficult to choose the suitable ones according to raw water source characteristics.

The aim of this study is to specify the design criteria values for presedimentation basin treating the water of Shatt Al-Arab River.

To satisfy this aim, experimental work was conducted including 51 plain sedimentation experiments and 37 particle size distribution analyses.

The work results were used to determine the values of surface overflow rate and detention time in terms of actual and theoretical efficiencies of presedimentation basin.

The study results indicated that, to use a presedimentation basin in treating the water of Shatt Al-Arab River and other rivers, which have suspended solids with do values varying over the range (7.4-20.9) um at efficiency exceeding 50%, the surface overflow rate must be less than 0.5 m/day and the detention time must be greater than 12.3 hr.