Combustion catalytic treatment of exhaust gas, combustion catalytic equipment, catalytic combustion system

The combustion catalytic treatment of waste gas, combustion catalytic equipment, and catalytic combustion system equipment system are composed of four major systems: activated carbon adsorption system, catalytic combustion regeneration system, electrical control system, and ventilation pipeline (valve) system.

① Activated carbon adsorption system: including the adsorption box body, activated carbon, instrument valves, fan motors, etc.

② Catalytic combustion regeneration system: including electric heating chamber, catalytic combustion chamber, heat exchange chamber, connecting pipes, instrument valves, electric heating pipes, catalyst, fan motor, etc.

③ Electrical control system: including PLC control cabinet, touch screen, instruments, electrical pipelines, etc.

④ Ventilation duct system: including all connecting pipes, valves, etc.

The working process of this device can be divided into two stages: activated carbon adsorption stage and activated carbon desorption regeneration stage. The working principles of the two stages are as follows:

① Activated carbon adsorption process:

The exhaust gas discharged from the workshop enters the activated carbon adsorption bed through pipelines. When the organic exhaust gas passes through the activated carbon, the organic components in the exhaust gas are attracted to the micropores of the activated carbon and concentrated to retain them. Other gases pass through the activated carbon and are discharged by a fan.

② Activated carbon regeneration process:

After using activated carbon for a period of time and adsorbing a certain amount of solvent, its adsorption capacity will decrease or lose. At this time, activated carbon needs to be desorbed and regenerated. After regeneration, activated carbon can resume its adsorption function and continue to be used. When regenerating, start the power supply of the catalytic combustion device's heating chamber, heat the air, and send the heated gas into the adsorption box. After the activated carbon is heated in the box, the solvent adsorbed by the activated carbon evaporates, and the solvent is sent to the catalytic combustion chamber for combustion by a fan. After combustion, it decomposes to generate hot air such as CO2 and H2O vapor. Part of the hot air returns to the activated carbon adsorption box to continue heating the activated carbon, and the rest is discharged. The activated carbon can be regenerated by circulating the hot air multiple times inside the activated carbon.

Introduction to Main Components of the Equipment

① Activated carbon adsorption bed:

The adsorption system adopts two adsorption beds in parallel, and in order to save space, the two adsorption beds are stacked up and down. Due to the presence of high-temperature gas in the activated carbon bed during desorption regeneration, the adsorption bed adopts double-layer insulation measures. ② Catalytic combustion device:

The exhaust gas heating adopts a pollution-free and stable electric heating method. The total power in the electric heating room is 24kw. The electric heating tubes are divided into two groups and are automatically controlled by the electric control box. When the exhaust gas temperature is below a certain temperature (can be set), the electric heating tubes will automatically turn on the power to heat the exhaust gas. When the exhaust gas temperature exceeds a certain temperature (can be set), the electric heating tubes will automatically disconnect one, two, or all power sources to save energy and achieve safe operation. The electric heating tube is made of heat-resistant and durable stainless steel.

The catalytic combustion device consists of an inner liner and an outer shell, with insulation materials filled between the inner and outer shells to ensure that the temperature of the outer wall of the furnace is below 60 ℃, in order to prevent scalding of operators and save energy. The inner liner and outer shell are made of carbon steel material. The catalytic combustion device has added a tubular heat exchanger. When the high-temperature gas after combustion passes through the heat exchanger, it will transfer some of the heat energy to the untreated low-temperature organic waste gas, making full use of the heat energy and saving energy.

The catalyst in the catalytic chamber is made of KMK-22 spherical particle catalyst produced by Zhejiang University, supported by aluminum oxide, and coated with platinum and palladium on the surface.

③ Activated carbon:

Select honeycomb shaped activated carbon for adsorption. Specification of activated carbon: 100 × 100 × 100 honeycomb activated carbon with a larger specific surface area. Honeycomb shaped activated carbon has low fluid resistance. Cellular activated carbon is not sensitive to paint mist. Activated carbon filling amount: the quality and quantity of activated carbon

The purification efficiency of exhaust gas treatment equipment is determined, so it is necessary to reasonably allocate the amount of activated carbon filling on the basis of ensuring qualified emissions.

④ Electrical control system:

The electronic control system has both manual and automatic control functions.

When manually controlled, each device can be started independently; During automatic control, all devices automatically start according to the program.

This control system collects various on-site data and signals through PLC to achieve monitoring functions such as data detection, data storage, and dynamic screen display. For operational accidents, it can automatically judge and accurately reflect the fault status, fault time, and related information in advance, and alarm in a timely manner. The fault code is displayed in text form. The entire system can operate normally, stably, safely, efficiently, and with low consumption.

Each control circuit is equipped with protection systems such as air switches, fuse fuses, and thermal relays to ensure safe operation of the system.

The fan motor is equipped with short circuit and overload protection devices to ensure and extend the service life of the motor.

⑤ Ventilation ducts, valves, fans

All connecting pipes are made of carbon steel plates.

Control the flow rate inside all pipelines within 10-15 meters per second.

The adsorption inlet (outlet) valve and regeneration inlet (outlet) valve of the above adsorption bed are both pneumatic valves, which have good sealing, flexible opening, and are sturdy and durable.

○ Fan model power:

Name, Model, Power, Flow, Total Pressure, Quantity

Adsorption fan 4-72-4.5 type 7.5kw * * 16m3/h 2479Pa 1 unit

Regenerative fan 9-12-3.15 type 1.5kw 1139m3/h 2416Pa, 1 unit

Cooling fan 4-72-2.8 type, 1.5kw, 1310m3/h, 966Pa, 1 unit

The catalytic combustion equipment has advanced design principles, unique materials, stable performance, simple operation, energy-saving and labor-saving, safety and reliability, no secondary pollution, and low operating costs. The desorption time and desorption cycle can be determined based on usage. The desorption time of the charcoal box is generally 5-10 hours, and the desorption cycle is once every 10-15 days. The activated carbon bed that adsorbs organic waste gas can be desorbed and regenerated by catalytic combustion of waste gas. The desorbed gas is sent to the catalytic combustion chamber for purification, without the need for additional energy, with low operating costs and significant energy-saving effects. The catalytic combustion chamber adopts ceramic honeycomb precious metal catalysts, which have low resistance and high activity. When the organic vapor concentration reaches 2000PPM or above, it can maintain spontaneous combustion, fully automatic control, simple operation, and convenient maintenance.

The adsorption concentration regeneration catalytic combustion equipment (CO) consists of 3-7 unit adsorbers, which can simultaneously or independently perform adsorption operations to concentrate high air volume and low concentration organic waste gas into low concentration flow rate and high concentration organic waste gas. The concentrated high concentration gas is connected to the regeneration catalytic combustion equipment for oxidation treatment (high-temperature blow off combustion), where the regenerated activated carbon is used as an adsorbent material to restore its adsorption capacity. The regeneration operation cannot be performed simultaneously, only one adsorber can perform desorption operation simultaneously. This treatment process can be widely used to purify low concentration organic waste gases generated in industries such as petroleum, chemical, rubber, paint, paint, furniture, household appliances, printing, etc. The types of organic substances that can be treated include benzene, ketones, alcohols, ethers, alkanes, etc.