Activated Carbon Adsorption Box

Activated carbon adsorption box is the core environmental protection equipment for the treatment of organic waste gas by using the porous adsorption characteristics of activated carbon, with high VOCs (volatile organic compounds) removal rate, stable operation and easy operation as the core advantages, widely used in spraying, printing, chemical, pharmaceutical, electronics and other industries, can effectively adsorb benzene, toluene, xylene, ethyl acetate, acetone and other organic pollutants, is the key treatment device for industrial waste gas to meet the emission standards, often with spray towers, catalytic combustion equipment, etc. to form a combined purification system.

From the perspective of structural design, the activated carbon adsorption box mostly adopts a modular vertical or horizontal box structure, and the core is composed of five parts: intake pretreatment unit, activated carbon adsorption layer, airflow distribution device, air outlet unit, and maintenance components. The material of the box can be carbon steel (anti-corrosion coating), stainless steel (304/316L) or PP according to the nature of the exhaust gas, which is suitable for different corrosive environments; The intake air pretreatment unit is equipped with a primary filter or defogging layer to intercept dust and droplets in the exhaust gas to avoid clogging the activated carbon pores. The adsorption layer is filled with columnar, granular or honeycomb activated carbon, and the filling amount is calculated according to the treatment air volume and exhaust gas concentration>. The airflow distribution device passes through the deflector plate or porous plate to ensure that the exhaust gas passes evenly through the adsorption layer to avoid local adsorption saturation. The maintenance components include access doors, activated carbon replacement ports and observation windows, which are convenient for regular inspection and packing replacement.

Its working principle is based on the "physical adsorption" mechanism: after the exhaust gas containing VOCs is pretreated, it enters the adsorption box from the air inlet, and passes evenly through the activated carbon adsorption layer under the guidance of the airflow distribution device. The rich micropores and mesopores on the surface of activated carbon form strong adsorption, trapping and fixing the organic molecules in the exhaust gas in the pores to achieve the separation of pollutants and gases. The purified gas (VOCs removal rate usually reaches 85%-90%) is discharged through the gas discharge unit to meet the standards. When the adsorption of activated carbon reaches saturation (judged by the difference in VOCs concentration at the entrance and export or the monitoring of equipment resistance), it is necessary to stop the machine and replace it with a new activated carbon, or desorption and regeneration of the saturated activated carbon (suitable for regenerative adsorption boxes with desorption systems) to restore the adsorption capacity.

Compared with other VOCs treatment equipment, the activated carbon adsorption box has obvious advantages: high purification efficiency and stable removal effect on low and medium concentrations (50-1000mg/m³) VOCs; It has strong adaptability, can handle a variety of organic waste gases, and the equipment starts and stops flexibly, suitable for intermittent production conditions; The cost is controllable, the initial investment of equipment is low, and daily operation and maintenance only need to be replaced regularly with activated carbon, which is less difficult to operate. High safety, the box is equipped with explosion-proof ports, temperature sensors and other safety components to avoid safety risks caused by the accumulation of organic gases.

However, it should be noted when using it: when dealing with high concentrations (>1500mg/m³) VOCs, they need to be diluted or pretreated first to prevent rapid saturation of activated carbon; The exhaust gas temperature should be controlled below 40°C and the relative humidity should be < 80% to avoid high temperature and high humidity affecting the adsorption efficiency. Saturated activated carbon is a hazardous waste that needs to be disposed of by a qualified unit and cannot be discarded at will. In general, activated carbon adsorption boxes have become the basic equipment for industrial VOCs treatment due to their high adaptability and cost-effectiveness, and play an important role in promoting enterprises to meet environmental protection standards and improve air quality.