This paper presents plasma technology for pulverised-coal ignition and improving energy efficiency of power stations. Plasma–fuel systems (PFS) were developed to accomplish this technology. PFS are a combination of pulverised-coal burners with arc plasmatrons. The main idea of the technology using PFS is to replace the traditionally used fuel oil for flame stabilisation and starting coal-fired boilers with the products of plasma chemically treated pulverised-coal. The coal–air mixture is fed into the PFS where the plasmatron induces heating, devolatilisation and gasification of the coal particles and partial oxidation of the char carbon. As a result, a highly reactive two-component fuel (mixture of combustible gases and partially oxidised char particles) is formed at the exit of the PFS. At the entry to the furnace, this highly reactive two-component fuel is easily ignited. PFS increase the efficiency of coal ignition and combustion, eliminate fuel oil expenditure for boiler start-up and flame stabilisation and decrease unburned carbon, nitrogen oxides (NOx), sulfur oxides (SOx) and vanadium (V) oxide emissions. PFS have been tested at 30 coal-fired power stations and steam coals of all ranks were used. The volatile content of steam coals varied from 4 to 50%; ash from 15 to 56%; and heat of combustion from 6700 to 25 000 kJ/kg.
A review of the developed plasmachemical technologies of pyrolysis, hydrogenation, thermochemical treatment for combustion, gasification, radiation-plasma, and complex conversion of solid fuels, including uranium-containing slate coal, and cracking of hydrocarbon gases, is presented. The use of these technologies for obtaining target products (hydrogen, carbon black, hydrocarbon gases, synthetic gas, and valuable components of the coal mineral mass) meet the modern experimental and economic requirements to the power sector, metallurgy and chemical industry. Plasma coal conversion technologies are characterized by a small time of reagents retention in the reactor and a high rate of the original substances conversion to the target products without catalysts. Thermochemical treatment of fuel for combustion is performed in a plasma fuel system, representing a reaction chamber with a plasmatron, while other plasma fuel conversion technologies are performed in a combined plasmachemical reactor of 100 kW nominal power, in which the area of heat release from the electric arc is combined with the area of chemical reactions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.