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This paper investigates a new concept for the CO2 emission mitigation in the ceramic industry based on carbon reduction and methane formation. The concept is analysed as a retrofit to the natural gas fuelled ceramic kiln that represents the main responsible of this industry in terms of energy consumption and exhaust emissions. The carbon dioxide conversion to methane is obtained by reduction with hydrogen on a Ni catalyst and thus methane is used to fuel the standard burners that equip the kiln. The paper addresses different sources for the hydrogen used as a feedstock for the proposed concept as well as alternative catalysts are explored and compared in terms of reduction efficiency and costs. A lumped and distributed parameter simulation of the entire ceramic kiln is combined to the CFD simulation of the reactor to estimate the efficiency of the CO2 reduction and the corresponding methane production for a reference ceramic kiln. The results of the numerical simulations are then employed to discuss the potential benefits of the proposed concept in terms of carbon dioxide emission reduction for the ceramic production. An economic assessment of the system analysed is also carried out concept to determine the investment necessary to implement the technology in an existing ceramic kiln. The potential replicability for other industrial sector is also addressed.

Aiming at the energy efficient use and valorization of carbon dioxide in the framework of decarbonization studies and hydrogen research, a novel dielectric barrier discharge (DBD) reactor has been designed, constructed and developed. This test rig with water cooled electrodes is capable of a plasma power tunable in a wide range from 20W to 2 kW per unit. The reactor was designed to be ready for catalysts and membrane integration aiming at a broad range plasma conditions and processes, including low to moderate high pressures (0.05–2 bar). In this paper, preliminary studies on the highly endothermic dissociation of CO2, into O2 and CO, in a pure, inert, and noble gas mixture flow are presented. These initial experiments were performed in a geometry with a 3 mm plasma gap in a chamber volume of 40cm3, where the process pressure was varied from few 200 mbar to 1 bar, using pure CO2, and diluted in N2. Initial results confirmed the well-known trade-off between conversion rate (up to 60%) and energy efficiency (up to 35%) into the dissociation products, as measured downstream of the reactor system. Improving conversion rate, energy efficiency and the trade-off curve can be further accomplished by tuning the plasma operating parameters (e.g. the gas flow and system geometry). It was found that the combination of a high-power, water-cooled plasma reactor, together with electronic and waveform diagnostic, optical emission and mass spectroscopies provides a convenient experimental framework for studies on the chemical storage of fast electric power transients and surges. [ABSTRACT FROM AUTHOR]