Sustainable sanitation and water pollution control calls for adoption of affordable and efficient wastewater treatment technologies. In the developing countries, the safe management of wastewater is not widespread. There is therefore a need for an appropriate technology that can reliably achieve acceptable effluent quality for discharge to the environment at minimal cost. Constructed wetland (CW) systems have been used as a cost effective alternative to conventional methods of wastewater treatment. However, the mechanistic understanding of the CW has not matured, while performance data that can guide design and operation of CW under tropical climate are scarce.
This study explores the treatment of domestic wastewater with subsurface constructed wetlands, in order to provide performance data that can influence design and operation of CW under tropical conditions and to evaluate the processes involved with the transformation and degradation of organic matter and nutrients.
The thesis contributes to performance data and getting a better mechanistic understanding about the factors influencing the performance of horizontal subsurface flow constructed wetland (HSSF-CW) treating real domestic wastewater under tropical conditions. The findings obtained in this research may prove useful towards the wider application of the constructed wetland wastewater treatment technology and the optimization of full-scale HSSF-CW.
Chapter 1: General introduction
Chapter 2: Use of the macrophyte Cyperus papyrus in wastewater treatment
Chapter 3: Performance evaluation of horizontal subsurface flow constructed wetlands (HSSF-CW)
Chapter 4: Performance comparison and economics analysis of waste stabilization ponds and HSSF-CW treating domestic wastewater
Chapter 5: Reactive transport simulation in a tropical HSSF-CW treating domestic wastewater
Chapter 6: Simulation of carbon, nitrogen and sulphur conversion in batch-operated experimental wetland mesocosms
Chapter 7: Biofilm modeling of batch-operated experimental wetland mesocosms
Chapter 8: General discussion and outlook
IHE Delft PhD programme leads to a deepening of a field of specialisation. PhD fellows do scientific research, often with conclusions that directly influence their region. At IHE Delft, PhD researchers from around the world participate in problem-focused and solution-oriented research on development issues, resulting in an inspiring research environment. PhD fellows work together with other researchers from many countries dealing with topics related to water and the environment.
PhD research is often carried out in the ‘sandwich’ model. Preparation and final reporting – the first and last portion of the programme – are carried out in Delft, while actual research is done in the fellow’s home country, under co-supervision of a local institute. Regular contacts with the promotor are maintained through visits and long-distance communication. This enables researchers to employ solutions directly to problems in their geographical region.
IHE Delft PhD degrees are awarded jointly with a university. The degrees are highly valued and fully recognised in all parts of the world.