Research on the Energy Characteristics of a Transferred Arc Plasma-Chemical Reactor for Waste Treatment +
Footnote †: This paper is an extended version of paper published in the international conference: 8 th International Conference on Sustainable Sustainable Solid Waste Management, Thessaloniki, Greece, 23-26 June 2021.
is unsuitable for decomposing such waste. At temperatures of 450-800 \({}^{\circ}\)C (pyrolysis) or up to 1000 \({}^{\circ}\)C (burning), new toxic compounds such as dioxins, furans, and other hazardous substances may form [3], which are much more harmful than the initial product. To fully counteract the effects of harmful substances on the environment and human health, it is necessary to recycle them at significantly higher temperatures, reaching 1100-1700 \({}^{\circ}\)C. At such temperatures, the molecules of the toxic compounds are broken into atoms, radicals, electrons, and positive ions, and simple harmless substances are formed with decreasing temperature. Thermal plasma technology is best suited for this purpose. Waste is usually destroyed using arc plasma generated by a plasma torch. The main advantage of plasma waste recycling (when compared to physiochemical or biological recycling) is its versatility, allowing for the decomposition of any kind of waste [4; 5; 6; 7; 8; 9; 10; 11]. Therefore, waste processing technology using plasma energy sources was studied experimentally in the present work. All hazardous waste decomposition facilities are subject to high-risk and special technical, occupational safety, and environmental requirements. They can only be guaranteed using modern scientific and technical knowledge and precision measuring equipment. The main requirement for a waste decontamination plant is not the only achievement of limited emissions of toxic substances after neutralization, which should not exceed permissible levels. Emissions must be minimized in all cases of the destruction process. This is possible when a processed substance is broken down into harmless compounds for humans and the environment. This study requires an experimental procedure to determine the necessary temperature, main and additional gas flow rates, and composition needed for chemical reactions (O\({}_{2}\), H\({}_{2}\), water vapor, etc.) to analyze the exhaust gas and solids formed and then start the industrial neutralization of the given material. Currently, the destruction of hazardous substances with a melting point higher than 1400 \({}^{\circ}\)C is very complicated and expensive using traditional technologies. In many cases, arc plasma technologies are more economical and acceptable for ecological and environmental protection. Thermal plasma is an excellent tool that significantly accelerates all the processes involved in the processing and decomposition of materials. It is important for recycling or disposing materials with high melting points. Plasma treatment is a technology in which fundamental and applied science and manufacturing are strongly interconnected. The thermal properties of plasma, such as the very high temperature and the high concentration of energy in a small volume and the ability to be heated to the required temperature of any gas, allow for processes that are not possible at moderate temperatures at atmospheric pressure. The use of arc plasma generators (plasma torches) in the industry enables the realization of many processes, such as reducing metal oxides, the synthesis of nanoparticles of metals and materials with a very high melting point, and many others, without the use of additional chemical processing. This process can be realized using a unique plasma-chemical reactor (PChR) device. This technology is suitable for small or large-scale production runs, and the process can be fully automated. This technology can also be used to decontaminate a variety of harmful and hazardous waste. High-temperatures and dense energy concentrations in a small volume completely break down harmful substances into their components and decompose them into environmentally friendly products.