Design of a Wastewater Hydroelectric Generator HD

Presentation of my dissertation project for completion of the BEng mechanical engineering degree at Plymouth University. Abstract: The current focus of energy production is a movement from finite resources towards innovative, cost effective and sustainable renewable energy production. This design study looks at the feasibility of generating electricity from wastewater, a currently underutilised energy source. An in depth evaluation of various types of wastewater and turbines is crucial to the design of a feasible system. Industrial wastewater is most suitable for energy recovery due to its consistent volumetric flow rate. The wastewater produced from both the food and drink industry and the manufacturing industry was deemed to be most suitable. A pelton type turbine was chosen for resilience to erosion and blockages from wastewater as well as efficiency and ease of maintenance. Prototyping and testing was carried out to assess the efficiency of a pelton turbine within wastewater and verify areas of high erosion and blockage potential. The results of the research and testing were utilised to make modifications to the traditional set up of a pelton turbine during the design phase. Another key aspect to the design process was enabling the same generator to be used on multiple sites with a variety of different flow and head conditions. This enabled the design to be cost effective and have a low payback period. Material selection was vital in the reduction of erosive and corrosive effects, laser or flame hardened AISI 403 steel was discovered meet all the requirements for high wear components. It was concluded that energy recovery from wastewater systems is feasible and furthermore a comprehensive generation system can be designed to increase the financial feasibility when compared to custom built turbines.