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Improvement of night-soil management in Hanoi | |
Author | Nguyen Thanh Tung |
Call Number | AIT Thesis no.WM-01-15 |
Subject(s) | Night soil--Vietnam--Hanoi--Management |
Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering |
Publisher | Asian Institute of Technology |
Abstract | Hanoi, the national capital of Vietnam and has an urban area covering about 82 square kilometers with population of some 1.5 million people. In Hanoi, Hanoi Urban Environment Company (URENCO) is a major company undertaking the collection and treatment of nightsoil. It is estimated that UREN CO collects only about 30% of the daily generated nightsoil. An investigation of nightsoil characteristics of Hanoi, showed that the value of nightsoil quality parameters such as BOD, COD, SS, VSS, TKN vary in a wide range. A reasonable explanation of that is data of result given by a limited number of sampling sites, different volume of septic tanks and variable cleaning cycles. The data analysis showed that the values of BOD, COD, SS, VSS and TKN parameters are lower compared to published results from USA, Germany and Thailand. Because the basic data about volume of septic tank and cleaning cycles are not given. It is unfortunately impossible to give a clear reason for the detected deviations. As a great variation of specific volume of the tank from 0.03 to 1.15 m3 / capita are found, the hydraulic design (HRT) deems to be not suitable. Further to that a wide variation of cleaning cycles affect to the performance of septic tanks, too. It has been analyzed that the degradation in the septic tanks is minor degree. Composting of nightsoil with solid waste has been tested by aerobic static pile method with forced aeration. The variation of nightsoil portion in the waste piles changing from 18 to 33% revealed an improved temperature development above 67°C over 8 days. The degradation of organic matter over weeks was reasonable. An adjusted variation of the forced aeration flow rate might need an additional improvement. In generally, the current situation of the nightsoil management in Hanoi City shows that there is a need of a planned emptying program and an improvement of the septic tank performance giving guidelines for a minimum volume per capita. It has to be considered how to treat the nightsoil accordingly. Co-composting is an option however shows limitation of amount to be treated. An alternative for nightsoil treatment like co-treatment of nightsoil with wastewater in wastewater treatment plant is need for the future. |
Year | 2002 |
Type | Thesis |
School | School of Engineering and Technology (SET) |
Department | Department of Civil and Infrastucture Engineering (DCIE) |
Academic Program/FoS | Water Engineering and Management (WM) |
Chairperson(s) | Trankler, Josef |
Examination Committee(s) | Gupta, A. D. ;Visvanathan, C. |
Scholarship Donor(s) | DAAD |
Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2002 |