Effect of Tank Shape on Performance of Aeration Tank in Sewage Treatment

Abstract

This Study Was Made To Study The Use Of Circular Aeration Tanks Instead Of Rectangular One In Wastewater Treatment Plants. The Study Covered The Effect Of Tank Geometric Shape On Action Stability, Effective Parameters Homogeneity And Treatment Efficiency Inside The Aeration Tank And Its Reflection On The Final Sedimentation Tank Performance. A Pilot Scale Was Erected In Balaqs Wastewater Treatment Plant Pilot Consists From Two Lines One Circular Aeration Tank Followed By Final Settling Tank And Second Rectangular Aeration Tank Followed By Final Settling Tank For Comparison Purpose Under The Same Conditions. The Samples Were Taken Continuously For 5 Weeks From The Inlet, Outlet For (Bod, & Tss) To Measure The Aeration Removal Efficiency. Also Measurements Inside Both Types Of Aeration Tanks To Determine The Parameters Of Temperature & Do Distribution And Stability In Different Depths And Sides Of Tank. Also The Consumed Power Had Been Measured. The Results Shows That The Circular Aeration Tank Achieved Better Stability Inside The Tank With Minimal Variation In Both Of Do And Temperature That Varied Widely In The Rectangular Tank Between Different Depths And Also Longitudinally And In Cross Section Directions That Affects Mainly On The Tank Efficiency And The Consumed Power Needed For Surface Aerators Operation.The Circular Safe About 50% Of The Consumed Power That Also Safe In The Construction And Operation Costs For Such Treatment.