Tar formation is a significant issue during biomass gasification. Catalytic removal of tars with the use of nickel cata-lyst allows to obtain high conversion rate but coke formation on catalysts surface lead to its deactivation. Toluene decomposition as a tar imitator was studied in gliding discharge plasma-catalytic system with the use of 5%, 10% and 15% by weight Ni and NiO catalyst on Al2O3 (α-Al2O3) and Peshiney (γ-Al2O3) carrier in gas composition similar to the gas after biomass pyrolysis. The optimal concentration of nickel was identified to be 10% by weight on Al2O3. It was stable in all studiedinitial toluene concentrations, discharge power while C7H8 conversion rate remained high – up to 82%. During the process, nickel catalysts were deactivated by sooth formation on the surface. On catalysts surface, toluene decomposition products were identified including benzyl alcohol and 3-hexen-2-one.
Gliding discharge and coupled plasma-catalytic system were used for toluene conversion in a gas composition such as the one obtained during pyrolysis of biomass. The chosen catalyst was G-0117, which is an industrial catalyst for methane conversion manufactured by INS Pulawy (Poland). The effects of discharge power, initial concentration of toluene, gas flow rate and the presence of the bed of the G-0117 catalyst on the conversion of C7 H8 , a model tars compounds were investigated. Conversion of coluene increases with discharge power and the highest one was noted in the coupled plasma-catalytic system. It was higher than that in the homogeneous system of gliding discharge. When applying a reactor with reduced G-0117 and CO (0.15 mol%), CO2 (0.15 mol%), H2 (0.30 mol%), N2 (0.40 mol%), 4000 ppm of toluene and gas flow rate of 1.5 Nm3 /h, the conversion of toluene was higher than 99%. In the coupled plasma-catalytic system with G-0117 methanation of carbon oxides was observed.
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Artykuł przedstawia wyniki badania wyładowań niezupełnych w układzie uwarstwionym szeregowo ester syntetyczny-papier dla dwóch różnych wartości temperatury. Przedstawiony jest układ badawczy, sposób pomiaru oraz wyniki pomiarów i ich obróbki.
EN
Paper presents the results of partial discharges investigation in synthetic ester-paper setup for two different values of temperature. Article shows the measurement set-up, measuring procedure, data outcome and its analysis.
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Dla zapewnienia właściwych parametrów plazmy generowanej w plazmotronach prądu przemiennego należy odpowiednio ukształtować charakterystyki statyczne i dynamiczne źródła zasilającego. Przy projektowaniu źródła zasilania należy uwzględniać wpływ zmian parametrów fizycznych i chemicznych atmosfery jaka występuje w komorze wyładowczej reaktora plazmowego a także oddziaływanie ślizgającego się łuku elektrycznego na elektryczne parametry źródła.
EN
In order to guarantee proper characteristics of plasma generated in AC plasma reactors, static and dynamic parameters of power source should be properly formed. Under the power source designing process the influence of physical and chemical plasma gas parameters and their changes inside plasma reactor discharge chamber should be considered. The gliding arc discharge influence on electrical parameters of power source should also be taken into consideration.
The methane conversion into C2 hydrocarbons, carbon black, and hydrogen has been studied under non-equilibrium plasma conditions, using dielectric barrier discharges (DBD) and gliding discharges (GD) at low and medium temperatures at atmospheric pressure. It has been found that ethane is the main product of the filamentary DBD action in the mixtures CH4+Ar and the reaction rate depends mainly on the concentration of high-energy components being able to initiate the chemical transformations of methane. Using GD, two processes are observed: the methane conversion into unsaturated hydrocarbons C2 (mainly acetylene) and into carbon black. The energy density of GD and the methane concentration in initial gas mixtures (CH4+H2 and CH4+Ar) are the main parameters influencing the methane conversion rate and the unit energy consumption.
A gliding-discharge plasma reactor with a spouted bed of granular materials was developed for the study of the methane conversion into C2 hydrocarbons. It was found that the presence of ceramic grains moving across the discharge zone increased the methane conversion into acetylene and decreased the unit energy consumption.
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Plasma-catalytic processing may be an efficient way for the decomposition of tetrachloromethane and nitrous oxide. The silent and the gliding discharges combined with a catalytic bed have been applied. The gliding arc discharge combined with TiO" SiO2 (ąuartz glass), and y-Al,O, beds packing has been used for nitrous oxide processing in oxygen. The silent discharge stabilized dielectric barrier combined with TiO, bed packing has been applied for tetrachloromethane conversion to chlorine in argon and oxygen. The conversion ratę of nitrous oxide, as well as the coiwersion ratę of nitrous oxide to NO, was studied as a funetion of specific energy. The conversion ratę of nitrous oxide to elements and NO and the conversion ratę of nitrous oxide to NO increased when granular dielectric materials TiO,, SiO, (ąuartz glass), and y-Al,O3 were introduced into the discharge space. The effect of interelectrode space filling with granulated TiO2 on conversion ratę of CC14 to chlorine in silent discharge was observed.
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