Research and Development in Plasma Technologies
Plasma Treatment, Pyrolysis, Gassification, Destruction and Combustion of Medical, Biomedical & Hospital Waste
With the increase in the number of healthcare facilities and the occurrence of the COVID-19 pandemic, medical waste (MW) has become a critical issue concerning health risks, environmental pollution, and sustainability. health-care waste includes all the waste generated within healthcare facilities, research centers, and laboratories related to medical procedures. Generally, the term medical waste is used interchangeably with the term healthcare waste. Meanwhile, the variations in its definitions are used worldwide. Medical waste refers to any hazardous healthcare waste which is potentially infectious, pathological, pharmaceutical, cytotoxic, chemical, and radioactive wastes as well as any non-hazardous healthcare waste.
Medical waste plasma pyrolysis is a state-of-the-art technology for the safe disposal of medical waste. It is an environment-friendly technology, which converts organic waste into commercially useful by-products. The intense heat generated by the plasma enables the disposal of all types of waste including municipal solid waste, biomedical waste, and hazardous waste in a safe and reliable manner. Medical waste is pyrolyzed into CO, H₂ (CO, H₂, CO₂, H₂O, and CH₄), and hydrocarbons when it comes in contact with the plasma. These gases are burned and produce a high temperature. In the plasma pyrolysis process, the hot gases are quenched from 500° to 70°C in order to avoid recombination reactions of gaseous molecules that inhibit the formation of dioxins and furans. The gas analysis results reveal that toxic gases found after the combustion are well within the limit of the Central Pollution Control Board’s emission standards. The plasma environment also kills thermally stable bacteria.
Plasma gasification is one of the most promising techniques for waste treatment as a result of its high-temperature characteristics and lower hazardous emissions. Plasma is defined as the fourth state of matter which consists of radicals, free electrons, charged particles, and ions. During the transformation of a substance into the plasma phase, there are various chemical reactions, comprised of ionization, dissociation, and reassociation chains occurring in the fluid medium, which causes thermal dissociation of a substance. Through these features, thermal plasma generators are widely used in the energy industry for thermal processes, requiring high temperatures such as burning and pyrolysis.
Besides, the total PCDD/PCDFs generation by the plasma gasification of hospital solid wastes are found to be lower than 0.01 ng toxic equivalent (TEQ), which should not exceed 0.1 ng TEQ/m3 according to the limits of European Commission Directive 2000/76/EC. Plasma gasification can be a sustainable and eco-friendly alternative for the treatment of MW, whereas H₂-rich syngas can also be obtained during the process.
As the initial parameter and process design for medical waste in the Plasma Dynamics group, it is considered that any medical element holds a great potential hazard both for the environment and for the population; therefore, medical wastes must be disinfected before disposal without the escape of any even very small element into the external environment. The thermal process inside the plasma reactor without opening the container allows waste destruction with the highest degree of safety.
Plasma generators commonly used in plasma gasifiers can be indicated as microwave plasma torches (magnetrons, klystrons, etc), and transferred/non-transferred arc plasma torches. With the continuous supply of electricity and working fluid into these torches, high-temperature plasma jets up to 10,000 K can be achieved in the gasifier, which causes pyrolysis of feeding materials such as fuels and wastes. In many cases, the plasma medium is air, water, steam, nitrogen, carbon dioxide, or their mixtures. During the pyrolysis of the feedstock, syngas that contains considerable amounts of hydrogen (H2) and carbon monoxide (CO) is produced, which can be later used for electricity production with the usage of reciprocating engines or fuel cells.
Moreover, with our unique technology, valuable materials such as metallic substances (containing iron (Fe), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), etc.), or high-carbon-containing materials like graphite are captured in the residual slag, which can be collected as molten slag during the gasification process. The emissions emitted during the plasma gasification of MSW are stated as 18 ppm NOx, 6 ppm SOx, 5 ppm CO, 0.38 ppm HCl, and 0.43 mg/m3 dust, which are considerably lower than the limits of European Standards (159 ppm NOx, 19 ppm SOx, 10 mg/m3 CO, 7 ppm HCl, 10 mg/m3 dust).
Plasma Gasification Process
Plasma gasification is the incomplete oxidation of organic matters, converting them into a combustible or synthetic gas (a mixture of H2, CO, CO2, CH4, and other hydrocarbons). For waste containing inorganics, the inorganic fraction is vitrified into a non-leachable slag simultaneously. Compared with conventional gasification, it has a smaller installation and cleaner air emission but consumes more energy. Medical waste with high organic content is suitable for plasma gasification, which is an effective waste-to-energy technology.The plasma gasification process has the advantage of being able to produce syngas and other valuable products.
Plasma Pyrolysis Process
Pyrolysis refers to a process in which organic matter is thermally decomposed in the absence of oxygen to produce smaller molecules. More specifically for plasma pyrolysis, the products are only composed of CO, H2, and a small amount of higher hydrocarbons. For medical waste, these organic fractions are chiefly plastics, paper, and cloth items. There are three main products that are found after pyrolysis including fuel gas, char, and oil. Generally, not only waste type but also pyrolysis process type play significant roles in the variation of these pyrolysis products. On the basis of heating rate, pyrolysis process types can be classified into slow pyrolysis, fast pyrolysis, and flash pyrolysis . These processes are developed with various desirable goals, mainly for adjusting the final products.
Plasma Combustion Process
Plasma combustion (plasma oxidation) is a developed incineration process in which plasma torch is used as a heat source with excess oxygen. It has been claimed that the plasma provides various active species to enhance combustion and activate fuel oxidation pathways, especially at low and intermediate temperatures. This effect of plasma catalysis not only enhances combustion at a lower temperature but also reduces the air requirement. Unlike plasma pyrolysis and gasification, combustible components are not the major component of the off-gas after the plasma combustion furnace. Hence the addition of an afterburner relies on the quality of off-gas and input requirement of the subsequent units.
Eliminate the formation of hazardous substances such as dioxins, furans, NOx
Absence of combustion (oxidation) in the waste disposal cycle
The application of this technology does not lead to an increase in the cost of equipment for waste disposal
Computer Modeling and Simulation
We have a very powerful computer simulation team with extensive experience in this field, so we can provide high-quality simulation of processes of any plasma related systems using the most powerful software.
Plasma Technologies: R&D Better Design Engineering Simulation Faster Test Optimized Manufacturing Lowest cost to market
Research, Development, Improvement, Design, realization, production of a prototype and industrial sample
By very powerful team, which includes professors, young scientists and engineers with extensive experience in this field, we will be able to provide the high-quality research, development, improvement and design for any plasma related system.
Connections and scientific cooperation with various universities in this industry, give us a great opportunity to find a solution to even the most complex problems associated with plasma technologies.
We have great experience to realization and production of a prototypes for further research and improvement and data monitoring.