Environmental and construction design for a wastewater treatment plant

Abstract

Wastewater in Minieh-Dannieh is discharged to agriculture areas and to the Ouyoun ElSamak Lake and causes catastrophic problems. To diminish this damage that affect human and animal health, it is required to construct a municipal wastewater treatment plant (MWWTP) in the upper part of this caza. This project covers the environmental and construction design of this treatment plant. It studied the physical, biological and social aspects of Minieh-Dannieh Caza with a population growth for the next 25 years. In addition to the design calculations for each process of this plant, GPS-X, Sap, and AutoCAD software were used too. Medium size wastewater treatment plant is considered for this study. The proposed WWTP is designed to treat 9,372m3 /day. This flow is the estimated daily wastewater flow for the year 2040. Moreover, the WWTP effluent quality should meet the standards of wastewater reuse for crops irrigation set by the EU due to the lack of such standards in Lebanon. The proposed WWTP consists of preliminary, primary, secondary, disinfection, and sludge treatment processes. The preliminary system contains of: screens, grit chamber and equalization tank; the primary system consists of 2 rectangular primary clarifiers, the secondary treatment is an activated sludge system consists of 2 anoxic tanks, 2 aeration tanks, and 2 secondary clarifiers, Disinfection consists of chlorine contact tank while the last process is the sludge treatment that consists of sludge aerobic digester. After designing the WWTP, the GPS-X software version 6.1.1 is used to simulate the treatment processes and investigate the overall plant performance. AutoCAD is used to execute the engineering drawing of the design of primary clarifier as a sample. Finally, SAP2000 is used to design the steel quantity needed for the primary clarifier tank too.