This article introduces an example of using an adsorption catalytic combustion device to treat paint exhaust gas. Activated carbon fiber is used as an adsorbent, combined with a multi unit split flow combined adsorption bed, and a PLC computer is used to achieve continuous operation of the entire system. The actual operation results show that this technology has the advantages of high purification efficiency, energy conservation, consumption reduction, and high automation level for treating low coating paint exhaust gas

VOC catalytic combustion includes three basic processes: preheating, catalytic reaction, and heat recovery. The temperature of industrial VOC exhaust gas is usually low, and preheating is required before entering the catalytic reaction bed, usually using a heat exchanger for preheating. For low concentration and low temperature VOC exhaust gas, the combustion process cannot maintain its own thermal balance and requires the consumption of auxiliary fuel. The preheated VOC exhaust gas enters the catalytic reaction bed and undergoes flameless combustion on the surface of the catalyst, which is thoroughly oxidized and releases a large amount of heat energy. The purified airflow has a high temperature, and a heat exchanger is used to recover energy for preheating VOC exhaust gas, reducing auxiliary fuel consumption and avoiding thermal pollution to the environment. The VOCS exhaust gas catalytic combustion processes used in engineering applications both domestically and internationally mainly include regenerative catalytic combustion, heat recovery catalytic combustion, direct combustion catalytic combustion, and adsorption concentration catalytic combustion. The catalytic combustion produced by constant dust removal is adsorption concentration catalytic combustion.

Catalytic combustion characteristics

1) Low ignition temperature, fast reaction rate, and energy saving. During the catalytic combustion process, the catalyst plays a role in reducing the activation energy of the reaction between VOC molecules and oxygen molecules, and changing the reaction pathway. The catalytic combustion has a low ignition temperature, saving auxiliary energy consumption, and in some cases, it does not even require external heating.

2) High processing efficiency, low emissions of secondary pollutants and greenhouse gases. The purification rate of VOCS exhaust gas using catalytic combustion treatment is usually above 95%, and the main end products are CO2 and H2O

3) Widely applicable. Catalytic combustion can treat almost all hydrocarbon organic waste gases and odorous gases. For VOCS waste gas with low concentration, high flow rate, multi-component and no recovery value, using catalytic combustion method for treatment is economically reasonable.