Optimisation and performance evaluation of a push-pull ventilation system for high-temperature fume control in rubber vulcanisation workshops

To address the challenge of controlling high-temperature fume pollution in rubber vulcanisation workshops, this work proposes an optimised push-pull ventilation system aimed at enhancing pollutant capture efficiency while reducing ventilation energy consumption. By integrating a scaled-down experimental platform constructed based on similarity theory with computational fluid dynamics simulations, the direct capture efficiency (DCE) is introduced as a performance evaluation metric, overcoming the overestimation issue inherent in traditional capture efficiency definitions due to pollutant recirculation. Orthogonal experiments were employed to analyse the sensitivity of air-curtain and exhaust-hood parameters on the system’s capture performance. The results indicate that the exhaust flow rate has the most significant impact on DCE. The optimal parameter combination was determined as follows: a hood inclination angle of 15°, a hood height of 0.75 m, a supply air velocity of 6 m/s, an outlet width of 50 mm, and an exhaust flow rate of 6000 m3/h, achieving a DCE of 90.3%. The study further reveals that the push-pull system exhibits comparable capture capability for particulate matter with diameters up to 10 μm as for gaseous pollutants, whereas a decrease in emission temperature weakens the buoyancy of the fume plume, leading to a reduction in DCE.