Plate heat exchangers can be used in the ventilation system of chemical workshops to cool and reduce the temperature of high-temperature exhaust, transfer heat to fresh air, and achieve energy recycling. For example, in petrochemical plants, the high-temperature gas generated by the reaction is cooled by a plate heat exchanger and then subjected to subsequent treatment, which not only improves energy utilization efficiency but also protects subsequent equipment. At the same time, for the possible corrosive gases in the chemical workshop, corrosion-resistant plate heat exchangers can be used to ensure stable equipment operation and maintain good ventilation and air quality in the workshop.