Compressed air recirculation for aperture reduction of a solar dish reflector for biomass pyrolysis

Although solar pyrolysis is a promising method for biomass energy extraction, traditional solar biomass pyrolysis utilises large-scale solar reflectors to meet the high-temperature demand, which limits its applicability at an industrial level. Hence, recirculation of the heat transfer fluid is proposed to reduce the scale of the solar reflector. This research designs a series of solar pyrolysis furnaces with solar parabolic dishes and compares the simulation results of those with compressed air recirculation to a benchmark. Results show that the recirculation can lead to a 30% reduction in the aperture diameter, a doubled thermal efficiency, and an 80% decrease in electricity consumption and related CO₂ emission. The change of the aperture diameter with a variation of the direct normal irradiance is insignificant. These multiple benefits can provide valuable insights into the scale optimisation method and promote its applicability in industrial sectors.