Activated carbon waste gas treatment

Activated carbon is a relatively commonly used substance and is often used to eliminate formaldehyde in people's daily lives. Of course, activated carbon also has certain applications in some industrial sites. If activated carbon is used in large quantities, a certain amount of waste gas will be generated, which needs to be treated by certain methods. So, what methods can be used to treat activated carbon waste gas? The following will introduce it in detail.

By introducing organic waste gas directly into the condenser for adsorption, absorption, decomposition and separation, valuable organic matter can be recovered. This method is suitable for working conditions with high organic waste gas concentration, low temperature and small air volume. It requires auxiliary refrigeration equipment and is mainly used in the pharmaceutical and chemical industries. It is rarely used by printing companies.

(1) Direct adsorption method: Organic waste gas can be adsorbed by activated carbon, with a purification rate of more than 95%. The equipment is simple and the investment is small, but the activated carbon needs to be replaced frequently, which increases the work procedures of loading and unloading, transportation, and replacement, resulting in increased operating costs.

(2) Adsorption-recovery method: Use fiber activated carbon to adsorb organic waste gas, and use superheated steam to backwash it after it is close to saturation for desorption and regeneration; this method requires the necessary amount of steam to be provided.

(3) Adsorption-catalytic combustion method: This method combines the advantages of adsorption and catalytic combustion methods. It uses a new adsorption material (honeycomb activated carbon) for adsorption, and introduces hot air for desorption and analysis after being close to the water. After desorption, the exhaust gas is introduced into the catalytic combustion bed for flameless combustion to thoroughly purify it. The hot gas is recycled in the system, greatly reducing energy consumption. This method has the characteristics of stable and reliable operation, low investment, low operating cost and convenient maintenance. It is suitable for the treatment of large air volume and low concentration waste gas. It is the most mature and practical method for treating organic waste gas in China.

By using auxiliary fuels such as gas or oil to burn, the mixed gas is heated, so that harmful substances are decomposed into harmless substances under high temperature. This method has simple process and small investment, and is suitable for high-concentration and small air volume exhaust gas, but it has high requirements for safety technology and operation.

4. Catalytic combustion method

The waste gas is heated and converted into harmless and odorless carbon dioxide and water through catalytic combustion; this method has low ignition temperature, energy saving, high purification rate, easy operation, small footprint and large investment, and is suitable for high-temperature or high-concentration organic waste gas.

5. Absorption method

Generally, physical absorption is adopted, that is, the waste gas is introduced into the absorption liquid for purification, and after the absorption liquid is saturated, it is heated, analyzed, and condensed for recovery. This method is suitable for large-volume, low-temperature, and low-concentration waste gas, but it needs to be equipped with a heating and analysis recovery device, which has a large equipment size and a high investment.

6. Nano-electrolytic oxidation method

Nano-micro-electrolysis purification technology uses piezoelectric materials processed at the nano level. Under certain humidity conditions, it can generate electrical adsorption of nano-micro-electrolysis materials through the micro-electrolysis electric field and release a large number of hydroxyl negative ions to purify oxygen-demanding pollutants in the gas. It can not only remove most of the organic matter in the air, but also analyze inorganic odors such as ammonia nitrogen and hydrogen sulfide.