Up knowledge! How does VOCs catalytic combustion equipment work?

  Organic waste gas is a common pollutant discharged from petrochemical, light industry, plastics, printing, coating and other industries
Organic waste gas often contains hydrocarbon compounds (aromatics, alkanes, olefins), oxygenated organic compounds (alcohols, organic acids, etc
), nitrogen, sulfur, halogen and phosphorus organic compounds
If these waste gases are not treated and directly discharged into the atmosphere, it will cause serious pollution to the environment and endanger human health
The traditional organic waste gas purification methods include adsorption method, condensation method and direct combustion method
These methods often have the disadvantages of easy secondary pollution, high energy consumption and easy to be limited by the concentration and temperature of organic waste gas
The emerging VOC catalytic combustion device has moved from experimental stage to engineering practice, and has been gradually applied to petrochemical, pesticide, printing, coating, wire processing and other industries

 
 
The waste gas catalytic combustion equipment uses the adsorption catalytic combustion process to recover and purify the low and medium concentration waste gas
The process is as follows: the organic waste gas enters the adsorber equipped with high-efficiency adsorbent after dust removal and other pretreatment, and the air is purified
With the progress of adsorption, the adsorbent gradually reaches saturation
In the process of contact with high-temperature hot air, the organic waste gas is desorbed to form highly concentrated waste gas, and the adsorption bed is regenerated at the same time
The regenerated adsorption bed can carry out adsorption operation again
The concentrated waste gas formed by desorption enters the catalytic burner to generate carbon dioxide and water, which can be discharged up to standard

The catalytic combustion process of waste gas catalytic combustion equipment is carried out in the catalytic combustion device
The organic waste gas is preheated to 200 ~ 400 ℃ through the heat exchanger before entering the combustion chamber
When passing through the catalyst bed, the molecules of hydrocarbons and oxygen molecules in the mixed gas are respectively adsorbed on the surface of the catalyst and activated
Because surface adsorption reduces the activation energy of the reaction, hydrocarbons and oxygen molecules oxidize rapidly at lower temperatures to produce carbon dioxide and water

Product features of waste gas catalytic combustion equipment:
 
 
1
Using the combined process of adsorption concentration and catalytic oxidation, the whole system realizes the closed cycle of purification and desorption process
Compared with the recycled organic waste gas purification device, it does not need to prepare additional energy such as compressed air and steam, does not produce secondary pollution in the operation process, and has low equipment investment and operation cost

2
The front end adopts dry high-efficiency dust filtering device with high purification efficiency to ensure the service life of the adsorption device

3
Special shaped honeycomb activated carbon is selected as the adsorption material, which has long service life of adsorbent, low resistance of adsorption system and high purification efficiency;
4
Using high-quality * palladium and platinum impregnated honeycomb ceramics as catalyst, the catalytic purification rate is more than 97%, the catalyst has long service life, low waste gas decomposition temperature, short desorption preheating time and low energy consumption

5
The activated carbon adsorption bed for adsorbing organic waste gas can recycle the hot gas after catalytic combustion for desorption and regeneration, and the desorbed gas is sent to the catalytic combustion chamber for purification treatment
When the concentration of organic waste gas reaches more than 2000ppm, it can maintain spontaneous combustion
No additional energy is required, the operation cost is low, and the energy-saving effect is remarkable

6
The waste gas catalytic combustion equipment adopts microcomputer centralized control system
The equipment operation and operation process are fully automated, and the operation process is stable and reliable

7
The safety facilities are complete
The safety fire damper is set in the air source and equipment room
During desorption, the desorption temperature entering the activated carbon bed is strictly controlled, and protective measures such as flame arrester, temperature sensing rod, explosion-proof port, alarm and automatic shutdown are set

Catalytic combustion applications
 
 
The catalytic combustion device of organic waste gas is mainly used for the purification and odor of harmful organic waste gas volatilized or leaked from coating, printing, electromechanical, household appliances, shoemaking, plastics and various chemical workshops
It is most suitable for organic waste gas with low concentration, which is not suitable for direct combustion or catalytic combustion and absorption and recovery treatment
Especially for the treatment occasions with large air volume, it can obtain satisfactory economic and social benefits

Catalytic combustion technology of organic waste gas refers to the rapid oxidation of hydrocarbons in organic waste gas into water and carbon dioxide at low temperature under the action of catalyst, so as to achieve the purpose of treatment

Catalytic combustion is applicable to the purification of toxic and harmful gases such as combustible gas and steam
However, for toxic and harmful gases such as a large number of dust particles and fog droplets, it is easy to cause the blockage of the catalytic bed, reduce the catalytic activity and reduce the purification efficiency
Catalytic combustion purification method is applicable to almost all industrial production processes that emit hydrocarbons or odorous compounds

technological process
Catalytic purification is a typical gas-solid catalytic reaction
Its essence is the deep oxidation of reactive oxygen species
In the process of catalytic purification, the function of the catalyst is to reduce the activation energy
At the same time, the catalyst surface has adsorption, which enriches the reactant molecules on the surface, improves the reaction rate and speeds up the reaction
With the help of catalyst, the organic waste gas can produce flameless combustion under the condition of low ignition temperature, oxidize and decompose into CO2 and H2O, and release a large amount of heat energy at the same time, so as to achieve the method of removing harmful substances in the waste gas
The device uses catalyst as intermediate to make organic gas harmless water and carbon dioxide at low temperature

catalyzer
 
 
Catalyst is the core of catalytic combustion method
A good catalyst must have the characteristics of high catalytic activity, good thermal stability, high strength and long service life

 
 
1
High activity
The activity of catalyst directly affects the chemical conversion of catalytic combustion
The conversion rate is not only related to the activity of the catalytic active material itself, but also directly related to the physical shape of the catalytic carrier
Therefore, while selecting suitable catalytic active materials, we must also consider the physical shape of the catalytic carrier to ensure that the catalyst has high activity and achieve the purpose of catalytic combustion purification

activated carbon adsorption
 
 
 
2
Good thermal stability
As the temperature of the exhaust gas changes at any time, if the catalyst can not adapt to the temperature change within a certain range, the performance of the catalyst will be reduced and the purification efficiency will be reduced
Therefore, the catalyst must be able to adapt to temperature changes within a certain range

3
High strength
In the process of catalytic combustion, the catalyst is often broken and worn due to high temperature, vibration, air flow and other factors
The cracking and wear will reduce the activity of the catalyst, increase the pressure drop of the catalyst bed and affect the purification effect

 
Zeolite adsorption
4
Long service life
Most of the catalytically active materials are expensive, so the catalyst with long service life should be selected as far as possible in the design

Selection and attention
 
 
1
The exhaust gas does not contain the following substances: grease with high viscosity
Phosphorus, bismuth, arsenic, antimony, mercury, lead and tin
High concentration of dust

2
When selecting equipment, please indicate the composition, concentration and outlet temperature of waste gas

3
The equipment installation site is free of corrosive gas and has good rainproof measures

4
Power supply required by the equipment: three-phase AC 380V, frequency 50Hz