Activated carbon, as an efficient adsorbent material, is widely used in waste gas treatment. However, in practical use, there are many problems with the activated carbon adsorption process. Numerical activated carbon will delve into these issues and provide corresponding solutions to improve the efficiency and safety of activated carbon adsorption processes.

One Small adsorption capacity
Question:
The physical adsorption of activated carbon has the problem of adsorption saturation. As the adsorbent is consumed, the adsorption capacity gradually weakens and eventually loses its adsorption function. This makes activated carbon unsuitable for high concentration exhaust gas treatment. In addition, activated carbon has poor adsorption capacity for mixed gases, and there is a mismatch between molecular diameter and activated carbon pore size, leading to frequent desorption phenomena.

Solution:
1. Optimize activated carbon materials: Select activated carbon materials with high specific surface area and appropriate pore size distribution to improve their adsorption capacity and efficiency.

2. Regular replacement of activated carbon: Establish a system for regular replacement and regeneration of activated carbon to ensure that it is always in the best working condition.

3. Use a multi-stage adsorption system: In high concentration exhaust gas treatment scenarios, a multi-stage adsorption system is used to gradually reduce exhaust gas concentration and improve overall adsorption efficiency.

II Temperature influence
Question:
The adsorption efficiency of activated carbon is significantly affected by temperature. Under normal circumstances, when the exhaust gas temperature exceeds 40 ℃, the adsorption efficiency of activated carbon rapidly decreases. In addition, VOCs adsorbed by activated carbon are prone to desorption when temperature or pressure changes, leading to secondary pollution.

Solution:
1. Pre cooling exhaust gas: Before adsorption of activated carbon, a cooling device is used to reduce the exhaust gas temperature to the appropriate adsorption temperature (below 25 ℃).

2. Constant temperature control: Add a constant temperature control device to the adsorption system to ensure temperature stability throughout the entire adsorption process.

3. High temperature activated carbon: Research and develop activated carbon materials suitable for high temperature conditions to enhance their adsorption capacity in high-temperature environments.

III Relative humidity impact
Question:
A high humidity environment will significantly reduce the adsorption efficiency of activated carbon. When the humidity exceeds 70%, the adsorption efficiency of activated carbon is less than 50% of its design standard.

Solution:
1. Pre treat moisture: Install dehumidification equipment before the activated carbon adsorption system to reduce the humidity in the exhaust gas.

2. Choose moisture resistant activated carbon: Use specially treated moisture resistant activated carbon to improve its adsorption performance in high humidity environments.

3. Layered adsorption: Using layered adsorption technology, the moisture in the exhaust gas is first removed through absorbent materials, and then activated carbon adsorption is carried out.

4 Air pressure influence
Question:
Activated carbon has a high adsorption efficiency in negative pressure environments, but in practical operation, the equipment cannot maintain negative pressure continuously. When the equipment stops running, the VOCs adsorbed by activated carbon will desorb and release, causing secondary pollution.

Solution:
1. Maintain negative pressure environment: Maintain the negative pressure environment inside the adsorption device through an automatic control system to reduce the desorption of VOCs.

2. Pressure stabilization device: Install a pressure stabilization device to ensure that the pressure change in the adsorption system is minimized when the equipment stops running.

3. Timely handling of desorbed gases: During the desorption process, methods such as re adsorption or combustion are used to promptly handle the released VOCs to prevent environmental pollution.

Five Influence of acidic gases
Question:
Activated carbon has a low adsorption capacity for acidic gases, while most VOCs are acidic. The surface acidity of activated carbon increases, and the adsorption efficiency further decreases.

Solution:
1. Acid gas pretreatment: Before entering the activated carbon adsorption system, methods such as alkali spray are used to neutralize the acidic components in the exhaust gas.

2. Modified activated carbon: Use chemically modified activated carbon to enhance its adsorption capacity for acidic gases.

3. Multi stage treatment: Add a pretreatment stage before the adsorption system to remove or reduce acidic components in the exhaust gas and improve subsequent adsorption efficiency.

VI Dust impact
Question:
The dust in the exhaust gas can clog the micropores of activated carbon, reducing its specific surface area and adsorption capacity, leading to the "poisoning" and deactivation of activated carbon.

Solution:
1. Dust pretreatment: Install efficient dust removal equipment before the activated carbon adsorption system to remove dust from the exhaust gas.

2. Regular cleaning: Establish a system for regular cleaning and replacement of activated carbon to prevent dust accumulation.

3. Choose anti blocking materials: Use anti blocking activated carbon materials to extend their service life.

7 Enterprises are prone to fraud and pose environmental risks
Question:
Although the activated carbon adsorption method requires less initial investment, the actual operation and maintenance costs are high and the management difficulty is high. Some companies engage in fraudulent behavior, such as not replacing activated carbon and using low iodine value as high iodine value activated carbon, which poses a huge environmental risk.

Solution:
1. Strengthen supervision: Environmental protection departments should strengthen supervision of enterprises and regularly inspect the use of activated carbon.

2. Transparent management: Enterprises should establish transparent management systems, record and disclose the replacement and regeneration of activated carbon.

3. Automatic monitoring system: Install an automatic monitoring system to monitor the operation status of the adsorption system in real time, ensuring that the adsorption effect of activated carbon meets the standard.

8 Used waste activated carbon is hazardous waste
Question:
The waste activated carbon after adsorbing VOCs is identified as hazardous waste, and improper treatment can cause secondary pollution.

Solution:
1. Standardized disposal: The management plan for waste activated carbon must be filed with the environmental protection department, and enterprises are not allowed to dispose of waste activated carbon without authorization.

2. Professional treatment: Entrust qualified units or individuals to dispose of waste activated carbon, ensuring that the treatment process meets environmental requirements.

3. Regeneration technology: Research and promote the regeneration technology of waste activated carbon to reduce the generation of hazardous waste.

Nine Post processing and its troubles
Question:
The treatment process of waste activated carbon is complex, and enterprises need to bear high management and disposal costs.

Solution:
1. Optimize management process: Simplify the management process of waste activated carbon, improve processing efficiency, and reduce the burden on enterprises.

2. Centralized processing center: Establish a centralized processing center to uniformly process waste activated carbon and reduce the disposal cost of individual enterprises.

3. Policy support: The government should introduce policies to support the research and development of waste activated carbon treatment and regeneration technologies, in order to alleviate the pressure on enterprises.


Ten Low safety
Question:
Most VOCs are flammable and explosive compounds, and the design and operation of activated carbon adsorption technology should fully consider safety.

Solution:
1. Safety design: When designing the adsorption system, fully consider safety measures such as fire and explosion prevention, such as installing spark arresters, explosion-proof valves, etc.

2. Regular inspection: Regularly inspect the safety facilities of the adsorption system to ensure its normal operation.

3. Employee training: Provide professional training to operators to enhance their safety awareness and emergency response capabilities.



The activated carbon adsorption process plays an important role in waste gas treatment, but there are many problems in its application process. By optimizing activated carbon materials, improving adsorption equipment, strengthening supervision and management, and promoting regeneration technology, the efficiency and safety of activated carbon adsorption processes can be effectively improved, achieving environmental standards. Enterprises and environmental protection departments should work closely together to promote the development and application of activated carbon adsorption technology, and contribute to environmental protection.