reatment of VOC waste gas with activated carbon fiber or honeycomb+ catalytic combustion system
1 Introduction to absorption, concentration and purification plant
Activated carbon organic waste gas uses activated carbon to absorb, concentrate and purify the organic waste gas.
(1) Absorption: Absorption and treatment of organic waste gas with activated carbon refers to that the organic solvent in the organic waste gas with high air flow and low concentration will be absorbed and concentrated in the organic carbon with the feature of organic carbon micropore of being able to absorb the organic matters. The absorbed and purified gas will be directly discharged after being qualified. Essentially, it is a physical absorption and concentration process. It does not process the organic solution.
(2) Desorption: Thermal desorption is used during desorption, and the electric heating tube of combustion furnace will heat the air, and blow the activated carbon tank under the driving of the fan to desorb the organic solution from the activated carbon and blow the concentrated high-concentration waste gas into the catalytic combustion bed. Under the effect of catalyst, organic matters will be treated with low-temperature chemical combustion under the catalytic initiation temperature of about 250℃, therefore, it will be safe and reliable and can solve the problem of the secondary pollution of activated carbon and realize the regeneration thoroughly.
2 Description of structure principle of catalytic combustion device
The regeneration of the absorbed and saturated activated carbon and the treatment of desorbed waste gas will be realized by two processes: desorption of hot air and catalytic oxidation. The hot air fan will feed the hot air from the catalytic purification system into the adsorption chamber for absorption and saturation for desorption. The concentrated organic waste gas from the desorption will enter into the heat exchanger of catalytic purification system, which will enter into the pre-heater and catalysis bed after exchanging the heat with the purified hot air upon reaction with catalysis bed and the temperature is improved. The catalytic oxidation temperature of catalysis bed is about 280℃. The concentrated organic waste gas desorbed will be oxidized on the catalysis bed to be decomposed as harmless gas, and the heat will be released (the temperature is 350℃-450℃ after reaction). Then, the organic waste gas will exchange the heat with organic waste gas from desorption system after passing through the heat exchanger, which will enter into desorption system as the desorbed hot air when the temperature reduces to about 150℃.
The operation of the purification plant consisting above process flows will be automatically controlled by PLC, which can realize the operation of the purification system in a continuous loop with waste heat after loop desorption and catalytic reaction.
Catalytic combustion method: It makes the organic gas to become harmless water and carbon dioxide under the low temperature with the catalyst as intermediate.
Low concentration waste gas treatment technology
