Catalytic combustion is a purification method that uses a catalyst to oxidize and decompose combustible substances in waste gases at lower temperatures. Therefore, catalytic combustion is also known as catalytic chemical conversion. As the catalyst accelerates the process of oxidation and decomposition, most hydrocarbons can be fully oxidized at temperatures between 300~450°C with the help of a catalyst. Little auxiliary fuel is needed for catalytic combustion, with low energy consumption and compact equipment size. However, issues such as catalyst poisoning, the replacement and cleaning costs of the catalyst bed, and high expenses affect the promotion and application of this method in industrial production processes. In the process of chemical reactions, the method of using a catalyst to lower the combustion temperature and accelerate the complete oxidation of toxic and harmful gases is known as catalytic combustion. Since the carrier of the catalyst is made of porous materials, which have a large specific surface area and appropriate pore size, when organic gases heated to 300~450℃ pass through the catalytic layer, oxygen and organic gases are adsorbed on the catalyst at the surface of the porous material, increasing the opportunities for contact and collision between oxygen and organic gases, enhancing activity, and causing a vigorous chemical reaction between the organic gases and oxygen to produce CO2 and H2O, while also generating heat. This transforms the organic gases into non-toxic and harmless gases. When designing catalytic combustion equipment, the following aspects should be considered: 1. Uniform air flow and temperature distribution. To ensure that the air flow and temperature across the catalyst surface are even, and to prevent the flame from directly contacting the catalyst surface, the combustion chamber must be of sufficient length and space. The catalytic combustion unit should have good insulation properties. The furnace body is typically lined with refractory material inside a steel structure shell, or a double-walled construction. 2. Easy to clean and replace. Catalyst reactors should generally be designed with a removable drawer structure for easy loading and unloading, facilitating the cleaning and replacement of the catalyst carrier. 3. Auxiliary Fuel and Combustion Aids. Catalytic combustion typically uses natural gas as auxiliary fuel, but can also utilize fuel oil, electric heating, etc. as auxiliary fuel. Combustion aid is generally provided by purified gas; if purified gas is not suitable for combustion aid, air should be introduced for combustion. 4. High conversion rates. As catalytic combustion is an irreversible exothermic reaction, it should be carried out at the highest possible temperature at any stage of the reaction to achieve higher conversion rates. However, operating temperatures are often limited by certain conditions, such as the heat resistance of the catalyst, the availability of high-temperature materials, the supply of thermal energy, and the presence of side reactions. Therefore, in actual production, appropriate choices should be made based on the specific circumstances.
































