HYDRAULICS OF WASTE WATER OUTFALL AND ENVIRONMENTAL IMPACTS

Abstract

In terms of the importance of waste water disposal, this research was initiated with the objective of designing a proper disposal outfall to help the community to develop and progress. The study area was chosen to be Adabya Port near Suez Gulf in Egypt where a waste water treatment plant discharges in the Gulf with a rate of 55,000m3/day causing near shore pollution. An analytical approach and a near field dilution hydrodynamic model were applied. Data was assembled. Many scenarios were proposed and simulated to detect the most effective location establishing the outfall including its diffuser. The governing factors were stratification and dilution. It was realized that dilution should not be less than 100 to guarantee the entrapment of discharged waste traces so as not to reach the water surface. This chapter presents the obtained conclusion and the recommendations for future research. VI.1. CONCLUSIONS The deduced conclusions were as follows: • Submerged discharges by diffuser are an effective way to dispose of degradable liquid waste in bodies of water.The study measurements of salinity and temperature profiles were combined with simulations of velocity in the water column, to determine the dilution and plume height of the wastewater disposal in Adabya Suez bay, by using Visjet Model. Scenario (A) showed the lowest efficiency in diluting the pollution and the waste water rise up to the water surface without any interaction from the ambient water body, this illustrates the importance of using long designed outfall and diffusers. Dilution in Scenario (B) has been achieved but there is no stratification layer. In Scenario (C) in both of trial (1 and 2) Dilution has been achieved with stratification phenomenon which guarantees that is no waste traces will appear on the water surface. Scenario C has been selected to be the best scenario for getting rid of the wastewater effluent without affecting the environment adversely.