Search

A gliding arc discharge (GAD) plasma reactor was developed for partial oxidative reforming (POR) H 2 production. Air was used as carrier gas and oxidant. The effects of the molar ratio of oxygen to carbon(O/C), input power and residence time on POR reaction were investigated. Under O/C ratio 0.75, input power 35 W and residence time 35 s, the energy yield of H 2 was 68.7 L/kWh and the main products were H 2 and CO. The GAD plasma was diagnosed with OES. A zero-dimensional(0-D) reaction kinetic model of was established. The simulation results were consistent with the experimental ones. The mechanism of C 12 H 26 conversion, the generation and consumption of products were discussed in detail. The experiment results were in good agreement with the simulated ones. The primary path of n -dodecane conversion was the direct cracking reaction and H 2 mainly derived from the recombination reaction between H atom and CH 4 , C 3 H 6 and C 2 H 6. [Display omitted] • A GAD reactor was used for POR of n -dodecane for hydrogen production. • A 0-D kinetic model was developed to explore the mechanism. • The results of OES were used to analyze the generation and consumption of substances. • The direct cracking reaction contributes the most to the n -dodecane conversion. [ABSTRACT FROM AUTHOR]

In this work, a knife-shaped gliding arc discharge (GAD) reactor driven by high frequency AC (HFAC) power was employed to convert CO 2 and CH 4 . The HFAC GAD exhibited good performance in dry reformation of CO 2 CH 4 . The development process with the HFAC GAD at a low gas flow rate was recorded and it is discussed with U - I waveforms and discharge images. The effects of input voltage, total gas flow rate, minimum electrode gap distance, and electrode thickness were investigated in terms of the CO 2 CH 4 conversion rate, selectivity of CO, H 2 , and C 2 hydrocarbons, specific energy density, and energy efficiency. The energy efficiency ranged from 1.58 to 2.21 mmol/kJ under changing operating conditions. The best conversions of CO 2 and CH 4 were achieved as 52.32% and 58.85%, respectively, with an energy efficiency of 1.65 mmol/kJ. [ABSTRACT FROM AUTHOR]

The current paper focuses on the miniaturization and utilization of the GlidArc® principle for the reforming of fuel gases (such as methane and propane) to synthesis gas (H2+ CO). The reforming characteristics and optimal operating conditions to achieve maximum synthesis gas yield were determined. Parametric screening studies were performed with different (i) atomic ratios of oxygen to carbon (O/C) in the range from 1 to 2, (ii) and feed flow rates from 2 to 10 L/min using alternating current voltage to produce the plasma in the reactor, which was varied from 2.8 to 4.6 kV. A Higher synthesis gas ratio of H2/CO ≈ 2.35 was achieved when methane was processed at O/C = 1 in comparison with propane (H2/CO ≈ 1.52). [ABSTRACT FROM AUTHOR]

Abstract: The influence of feed gases proportion on the performance of gliding arc discharge (GAD) plasma assisted methane reforming with carbon dioxide process (DMR) is investigated, especially focused on the reagents conversion, the main by-product distribution and the energy consumption. An additional analysis of the theoretical conditions of equilibrium and its comparison with the experimental results are also included. The GAD assisted DMR process is effective in converting CH4/CO2 into synthesis gas with C2H2 and C2H4 detected as the main hydrocarbon compounds. Strong dehydrogenation in the GAD assisted DMR process is suggested with no obvious C2H6 observed in the effluent and serious coke formation and deposition detected in the relative high CH4/CO2 feed ration and supply voltage condition. Compared to other plasma systems reported before, the GAD reactor used in current work shows lower energy consumption for methane conversion but higher energy consumption for C2H2 formation. The increase of CH4/CO2 molar ratio in the feed gases favors the reagents conversion and consequently promotes the formation of each by-product. Meanwhile, the by-product selectivities, the value of H2/CO ratio in the effluent, the coke formation, and the special energy consumption for reagents conversion and synthesis gas formation are shifted. It is clearly demonstrated that under some certain circumstances, the GAD plasma reactor assisted reaction can be totally out of thermodynamic equilibrium. [Copyright &y& Elsevier]

Conventional catalytic processes of conversion to produce synthesis gas require both high temperatures and high pressure. Non-thermal plasma is considered to be a promising technology for the synthesis gas production from methane since it can operate in ambient conditions. In this study, a multistage gliding arc discharge system was employed to investigate the effects of stage number, feed gas composition, feed flow rate, frequency, applied voltage, and electrode gap distance on the and conversions and the product distribution. The studied system consisted of four units of gliding arc discharge reactors connected in series, and the plasma generated across the gliding arc electrodes was AC current with different voltages and frequencies. In this study, air was used for the partial oxidation of methane. The results showed that increasing stage number, voltage, or electrode gap distance enhanced both and conversions in contrast with the effects of increasing molar ratio, feed flow rate, and frequency. The optimum conditions were found at a molar ratio of 3/1, a feed flow rate of /min, and a frequency of 300Hz for the maximum conversions of and with a high synthesis gas selectivity and a very low energy consumption. The energy consumption of the gliding arc discharge system was found to be low, about – (15.3–)/molecule of converted as compared to (21eV)/molecule of converted for the corona discharge system with pin and plate electrodes. [Copyright &y& Elsevier]