Comparative study of atmospheric pressure DC, RF, and microwave thermal plasma torches for waste to energy applications

Enhancement in living standards leads the world towards exponentially increasing population in urban areas, which causes a massive increase in municipal solid waste (MSW) production. It is proven that plasma technologies are beneficial for recycling materials and generating energy from various kinds of solid wastes. So, there is a high demand for potentially sustainable, environment and user-friendly, cost-effective, and highly efficient thermal plasma-based waste-to-energy facilities. Three different types of advanced thermal plasma technologies, such as atmospheric DC, RF, and Microwave plasma torches, are considered for waste treatment application at small and industrial scales. A comparative study was carried out for all three plasma torches for waste to energy and waste treatment applications. Furthermore, simulation modeling and experimental results of a lab-scale DC non-transferred and RF thermal plasma torch were presented. The results show that DC and RF plasma torches are economical and advantageous for large-scale waste treatment and energy output. At the same time, small-scale waste treatment could incorporate MW plasma torch. Therefore, technological advancement, minimization of environmental effects, and process economics are the most critical parameters for improving plasma-based waste treatment plant's feasibility and sustainability.