Investigations on the mitigation of ventilation air methane and energy recovery in site trial thermal flow-reversal reactor

In this paper, the key influencing factors on the ventilation air methane (VAM) utilization site trials were discussed. A new model of pressure loss and heat transfer between gas and solid phase in regenerative bed was innovatively developed. The factors of inlet gas flow rate, methane concentration fluctuations, the channel size in the monolith blocks and the energy recovery on the behaviors of site trial thermal flow-reversal reactor (TFRR) were studied systematically. Results show that the predicted temperature profile matched well compared with the site trial results. The shape of temperature profile in the reactor gradually evolves from M-shaped to boolean AND-shaped with the increase of the channel size of the honeycomb monolith bed. The residual methane concentration in the exhaust gas can be lower than that of 0.00079 vol% when the TFRR is filled with optimal monolith blocks with channel size of 3 x3 mm. Using the heat exchanger in the reactor, about 40% to 44% thermal energy can be recovered from the TFRR site pilot plant.