Treatment of Grey Water for Toilet Flushing Use

• Main Author: Abd. Razi, Naizaitul Husna
• Format: Final Year Project
• Language: English
• Published: Universiti Teknologi Petronas 2004
• Subjects: TP Chemical technology
• Online Access: http://utpedia.utp.edu.my/7821/1/2004%20-%20Treatment%20of%20Grey%20Water%20for%20Toilet%20Flushing%20Use.pdf; http://utpedia.utp.edu.my/7821/

This study is the preliminary study ontreating grey water for toilet flushing use. Due to the increment number of students in Universiti Teknologi PETRONAS (UTP), the accommodations are also increased. This will result the increasing need of water use, in future. Thus, the recycling of grey water is recommended to overcome the problem. The recycled grey water will be use for toilet flushing system in UTP student's village. The main objective of the study is to find ways to treat grey water as of to reduce highquality fresh water supply for toilet flushing purpose and to propose a grey water recycling system. Besides that, an economic study on using grey water for toilet flushing use was done. This project consists of two parts, which are to analyze the wastewater before and after treatment and to find the best treatment method using the available equipment in UTP by conducting a laboratory work. Based on the findings from the experiment, treatment methods are proposed to treat the grey water for toilet flushing use in UTP. Then, a brief economics analysis is required to check on cost and water saving if the treatment system is implemented in UTP. The methodology used for treatment of grey water including the experimental work that available in the UTP laboratory which is Coagulation and Flocculation, Sequencing Batch Reactor (SBR) and Chlorination. Other methods used are to analyze the parameters before and after the treatment. Results obtained from the experiment shown that the coagulation and flocculation treatment is the suitable method to treat turbidity of the grey water. The 70 mg/L alum dosages at pH 6.5 are the optimum value determined in order to reduce the turbidity. SBR treatment has shown a reduction in BOD for 1-hour time and chlorination method is able to reduce theMPN of total coliform with optimum chlorine dosage at 28 mg/L. Thecost study analysis shows that the water consumption and water bill saving is by 87 % and 84%, respectively.