Activated carbon adsorption box

The following is a detailed introduction to the activated carbon adsorption box:
Working principle
Adsorption process: Activated carbon has a microcrystalline structure, with irregularly arranged microcrystals. The crystal surface has micropores, transition pores, and macropores, and it has a huge inner surface and specific surface area. When the contaminated fluid (gas or liquid) passes through the activated carbon layer, due to the existence of unbalanced and unsaturated molecular forces or chemical bond forces on the surface of the activated carbon adsorbent, the pollutants are adsorbed on the microporous surface of the activated carbon, thereby separating from the gas or liquid mixture.
Dynamic equilibrium: As adsorption proceeds, activated carbon gradually becomes saturated and its adsorption efficiency decreases. When it reaches the adsorption saturation state, the activated carbon needs to be regenerated to restore its adsorption capacity.
Structural design
Box body: It is usually made of steel structure or stainless steel structure, and there are also those formed with PP plates of different specifications and thicknesses, which can effectively reduce leakage. The size of the box body is selected according to actual needs to provide sufficient adsorption area. Generally, it adopts a block design or drawer-type or modular structure, which is convenient for opening for maintenance and replacement of activated carbon.
Activated carbon layer: It is the core part of the adsorption box, and its thickness is determined according to the concentration and type of pollutants. For the treatment of organic waste gas, it is usually necessary to select porous activated carbon with sufficient specific surface area. Common types of activated carbon include granular activated carbon, honeycomb activated carbon modified activated carbon, etc.
Filter: Generally installed at the air inlet, it is used to filter out particulate matter in the exhaust gas, prevent the pores of activated carbon from being clogged, and extend the adsorption cycle. Commonly used filters include high-efficiency filters activated carbon filters, etc. High-efficiency filters can remove particles larger than 1μm, while activated carbon filters can filter out toxic and harmful gases and odors, etc.
Ventilation system: A reasonable ventilation design can enable the exhaust gas to flow evenly through the activated carbon layer, enhancing the adsorption effect. Ventilation design needs to take into account factors such as the flow rate, velocity, and direction of the exhaust gas to ensure that the exhaust gas can fully contact the activated carbon inside the box. Usually, a fan is set up to provide power to enable the exhaust gas to pass through the adsorption box smoothly.
Monitoring and safety system: including pressure gauge monitoring resistance to prevent system blockage; Install thermocouples in the adsorption bed layer to prevent spontaneous combustion caused by the accumulation of adsorption heat. It can be linked with concentration, temperature, and pressure sensors, automatically shut down and alarm in case of abnormality, and may also be equipped with an online VOC monitor to monitor the outlet concentration in real time to ensure compliance with emission standards.
Performance characteristics
High adsorption efficiency: It has a remarkable effect on the treatment of low-concentration and high-volume waste gas, with a single-stage adsorption efficiency of over 90%. It also has a significant removal effect on harmful gases such as benzene and VOCs.
Wide application range: It can handle various organic and inorganic pollutants, such as benzene, ketone, alcohol, ether, alkane and their mixed organic waste gas, acidic waste gas, alkaline waste gas, etc. It is widely used in multiple industries such as chemical engineering, coating, printing, electronics, pharmaceuticals, metallurgy, and machinery.
Easy maintenance: The structure is relatively simple, with no complex technical requirements. Regular equipment inspection and activated carbon replacement can be carried out. The activated carbon replacement of some equipment is relatively convenient, such as the activated carbon filter material layer with a drawer-box design, which is easy to operate.
Low operating cost: The regeneration cycle is long, usually 3 to 6 months, the operating energy consumption is low, about 0.1 to 0.3kW · h/m³ of exhaust gas, and the equipment occupies less space, which can save space.
Application field
Industrial waste gas treatment: Such as complex waste gas in the chemical industry, including hydrogen sulfide, formaldehyde, benzene series substances, etc. The spray painting waste gas in the coating industry contains VOCs such as benzene, toluene, xylene, and ethyl acetate. The waste gas containing ethanol, acetone, ink solvents, etc. in the printing industry can all be effectively treated through activated carbon adsorption boxes.
Air purification: In indoor environments, it can be used to remove harmful gases such as formaldehyde and benzene produced during decoration, as well as odors and smoke in the air, thereby improving indoor air quality. In some public places such as shopping malls, hospitals, and schools, it can also be used to purify the air and provide a healthy and comfortable environment.
Water treatment: It can be used for the purification of drinking water, removing organic matter, pigments, odors, heavy metal ions, etc. in water, and improving the quality of drinking water. In industrial wastewater treatment, it can also adsorb and remove certain pollutants, playing a role in pretreatment or advanced treatment, which is conducive to the standard discharge or reuse of wastewater.
Regeneration method
Hot air desorption: By using hot air (120-180℃) to purge saturated activated carbon, pollutants are discharged along with the airflow. It is suitable for non-heat-sensitive organic substances, such as benzene series substances, etc.
Steam desorption: By heating activated carbon with steam, pollutants are condensed and separated. It is suitable for high-boiling-point organic substances, such as ethyl acetate; however, subsequent wastewater treatment is required.
Catalytic combustion desorption (CO/RCO): The high-concentration waste gas after desorption is decomposed into CO₂ and H₂O through catalytic combustion. It is suitable for waste gas with low recovery value and can achieve an integrated process of "adsorption-desorption-purification".