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Influence of Ventilation And Decentralized Purification on Pollutant Control in Urban Highway Tunnels without Exhaust Shaft

Limited by multiple factors, such as land use planning, landscape coordination and environmental standards, the ventilation conditions of the urban highway tunnels are insufficient, and therefore the joint control of ventilation and purification becomes a necessary solution. In this study, the effect of number, location of decentralized purification equipment, and the tunnel ventilation rate on pollution in the tunnel are studied using one-dimensional calculation. The results show that the arrangement of purification equipment can reduce the design ventilation rate to a certain extent. When purification equipment is arranged, the maximum NO2 concentration can be reduced by up to 30.9%, and the average NO2 concentration can be reduced by up to 18.2% compared with that without purification. The purification equipment arranged in the rear section of the tunnel is conducive to reducing the concentration of pollutants at the exit, while the arrangement in the middle section of the tunnel is conducive to reducing the average concentration of pollutants in the tunnel.