Design and performance optimization of solar pyrolysis reactor for organic impurities in waste salt

The efficient removal of organic impurities in waste salt is significant for its recycling and environmental protection. In present paper, a solar pyrolysis reactor is proposed by integrating the parabolic trough concentrator (PTC) and solar reactor (SR). The results demonstrate that organic impurities react completely in 1290.7 s, and the thermal efficiency is up to 89.90 % at the initial temperature of 293.15 K and the reactor radius of 32 mm. However, the temperature difference (ΔT) in reactor is over 110 K. Based on this, the effects of initial temperature and reactor radius on pyrolysis results are explored. To improve the uniformity of temperature distribution and pyrolysis performance, a new pitchfork-shaped fin has been designed. Compared with no fins, the ΔT and reaction time are reduced by 54.99 % and 24.36 %, and the thermal efficiency is improved by 6.47 %. In comparison to traditional star-shaped fins, the ΔT is reduced by 13.1 %. Then, to further enhance the comprehensive performance of pitchfork-shaped fins, optimization on fin structure parameters is performed and validated. After optimization, the ΔT and reaction time are further reduced by 10.27 % and 2.3 %. The present work demonstrates that the PTC-SR is feasible for the efficient removal of organic impurities in waste salts, which is significant for the recycling and utilization of waste salt.