Factors Affecting Performance of Sewage Treatment Plant

The objective ofthis project is to study and find the optimum factors such as pH,
temperature and microbial nutrients that affect the performance of the sewage
treatment plant.
The problem to the project is to minimize the value ofBiological Oxygen Demand
(BOD) of an activated sludge sewage treatment plant. The effluent of a treatment
plant should meet the requirements ofEnvironmental Quality (Sewage and Industrial
Effluents) Regulations 1979.
The scope ofthis project would be limited to the aeration tank. Although there are
many other factors that can affect the performance of the treatment plant, pH,
temperature and microbial nutrients are identified for analysis.
In order to find the optimum conditions for a wastewater treatment plant, a multi
national company is identified as my case study. Then, literature reviews on the
activated sludge and other related issues are conducted to obtain background
information and previous study.
Experimental works was carried out to determine the value of Biochemical Oxygen
Demand (BOD) using BODTrak and Chemical Oxygen Demand (COD) using
digestion method. The analysis is conducted before and after the treatment at the
aeration tank. The data gathered from the experiments is then further analyzed in
terms of performance or percentage reduction ofBOD value.
It is found out that the optimum conditions for the BOD removal is at temperature
between 30°C to 31°C and pHof 7.5. The amount of Total Organic Carbon should be
higher than 50mg/L with the ratio of Carbon:Nitrogen:Phosphorus of 100:10:1. All
these are the nutrients for the synthesis of microorganisms in the treatment plant.