How should activated carbon be treated after adsorption saturation? This brings us to our next topic - the regeneration method of activated carbon after adsorption saturation, and let's see what technologies can help activated carbon regain its "new life".
After saturated adsorption of exhaust gas, the CTC adsorption value of activated carbon can be restored and reused through regeneration technology. In regeneration technology, the heating regeneration method is the most mature technology in industry. It uses high temperatures of 800-900 ° C to process organic matter in stages in an inert atmosphere or vacuum, allowing it to decompose or desorb. Rotary furnaces and other equipment can produce continuously, and the carbon tetrachloride adsorption value of regenerated activated carbon can be restored to 81% -92% of the original carbon, and processes such as microwave pyrolysis regeneration can even reach 95%.
Another pressure swing regeneration method utilizes the characteristic of equilibrium adsorption capacity changing with pressure in gas-phase adsorption. Through two stages of pressurized adsorption and depressurized desorption, the adsorbate is desorbed from the pores of activated carbon to restore adsorption performance. It has a mild operating temperature, low energy consumption, and does not rely on chemical agents or high-temperature equipment. It is suitable for processing low boiling point, volatile organic compounds and is commonly used in gas separation fields such as air to nitrogen production.
After saturation of activated carbon adsorption, its CTC adsorption value can be restored through regeneration technology. The low-temperature variable temperature regeneration method is based on the physical adsorption heat release characteristics. It gently raises the temperature from 100-250 ℃ to reduce the adsorption capacity, causing the adsorbate to desorb, and then lowers the temperature to restore the adsorption capacity. It is suitable for in-situ or offline regeneration of columnar activated carbon, with energy consumption only one-third to one-half of traditional high-temperature thermal regeneration.
The steam regeneration method is divided into low-temperature steam desorption and high-temperature steam activation. Low temperature steam desorption uses saturated/superheated steam at 100-150 ℃, heating the carbon bed to desorb organic matter, and the steam carries the desorbed material into the condensation recovery system; High temperature steam activation occurs in an anaerobic environment at 800-1000 ℃, allowing steam to undergo gasification reaction with residual carbon, thoroughly cleaning pores and restoring adsorption performance close to new carbon.
The regenerated activated carbon has significant application value and can be reused in waste gas treatment systems, such as adsorption towers, which can reduce operating costs and resource consumption, achieving resource recycling.