Sustainable Waste-water Derived Energy Generation System
The development of wastewaterderived energy system (EDI-SOFC) is feasible to fit into existing anaerobic treatment plants. The optimization of the system and its net energy balance assessment with different strength of wastewaters. The present groups AD, EDI and SOFC to convert energy in organics and nitrogen pollutants to electric energy. In this invention, the microorganism community of AD process metabolizes complicated organics to biogas and digestate containing NH₄+. Biogas collected and NH₃ gas converted into NH₄+ collected yield electricity. O₂ is not a need for NH₄+ removal from wastewater by EDI, which saves about 40% energy input for aeration of the nitrification and denitrification, but also produces less sludge yield. The effluent of EDI cathode recycles to AD and neutralizes H+, which can prevent from the inhibition of low pH and increase biogas yield. Conservative 50% electricity conversion efficiency can be obtained by SOFC fed with a mixed gas of biogas and NH3-H2 and 20% higher electricity conversion efficiency than 30% of gas fired turbine. This invention can help handling landfill leachate, digestate, wastewaters, sludge and positively net energy output can be realized.