Industrial waste gas treatment: generation, hazards and efficient treatment technology

Generation and hazards of industrial waste gas
Industrial waste gas is a gaseous pollutant generated in the industrial production process, mainly from fuel combustion, chemical reactions, material processing and other links. For example, incomplete combustion of coal or hydrogen fuel in coking, steel, cement and other industries will release gases such as carbon monoxide (CO) and nitrogen oxides (NOx); volatile organic compounds (VOCs) and hydrogen sulfide (H₂S) produced in the production process of chemical enterprises are typical by-products of chemical reactions.
These waste gases cause multiple hazards to the environment and human health:
Atmospheric pollution: CO, VOCs and NOx form photochemical smog under light, aggravating haze and ozone pollution;
Health threats: CO combines with hemoglobin to cause hypoxia, benzene substances in VOCs are carcinogenic, and H₂S causes respiratory damage;
Ecological damage: Sulfur oxides (SOx) and nitrogen oxides (NOx) cause acid rain and destroy the balance of soil and water.
Main ways and principles of industrial waste gas treatment
1. Combustion method
Convert combustible waste gas into CO₂ and H₂O through high-temperature oxidation.
Direct combustion: suitable for high-concentration exhaust gas, needs to maintain a high temperature of more than 800℃, and has high energy consumption;
Catalytic combustion: using catalysts (such as precious metals) to reduce the reaction temperature (200℃-400℃) and improve efficiency.
Application scenarios: VOCs treatment in petrochemical industry, CO purification in coking plants.
2. Adsorption and absorption method
Use porous materials or liquid absorbents to capture exhaust gas components.
Activated carbon adsorption: has strong adsorption capacity for VOCs and odorous gases, but the material needs to be replaced regularly;
Alkali solution absorption: for acidic gases (such as H₂S, SO₂), salts are generated through neutralization reaction.
Application case: A chemical fiber company uses electrostatic adsorption technology to treat texturizing machine oil fume exhaust gas, with a purification efficiency of over 95%8.
3. Catalytic oxidation technology
Promote the oxidation and decomposition of pollutants through catalysts, with both high efficiency and energy saving advantages.
Hopcalite: A composite catalyst composed of manganese and copper oxides, which can efficiently oxidize CO and VOCs at room temperature to medium temperature (0℃-150℃).
The catalyst has strong moisture resistance and is suitable for wet waste gas environments such as steel plants and coking plants.
4. Biological treatment method
Use microorganisms to degrade organic waste gas, which is suitable for low-concentration and high-flow scenarios.
Biofilter: The waste gas passes through the filter bed filled with microorganisms, and the pollutants are decomposed into CO₂ and H₂O;
Biotricking filter: Combine liquid absorption with microbial metabolism to treat sulfur- and nitrogen-containing waste gas.
5. Process coupling and resource utilization
Combining waste gas treatment with energy recovery to achieve "waste treatment with waste".
Waste heat utilization: A cement plant transports waste heat from high-temperature waste gas to a ceramic factory for energy supply, reducing coal consumption;
Hydrogen recovery: Fertilizer companies extract hydrogen from synthetic relaxation gas through membrane separation technology, with an annual recovery of 500 cubic meters/hour, which is used to produce steam or chemical raw materials.
The key role of hopcalite in waste gas treatment
As a high-efficiency oxidation catalyst, hopcalite has unique advantages in industrial waste gas treatment:
Low temperature and high efficiency: CO and some VOCs can be decomposed at room temperature without additional heating, reducing energy consumption;
Anti-humidity and anti-sulfur: Through the synergistic effect of metal oxides, the poisoning of water molecules and sulfides to active sites is reduced;
Long-life design: The honeycomb carrier structure (such as ceramic matrix) improves mechanical strength and adapts to high air velocity (>100,000 mL·g⁻¹·h⁻¹) environments, with a service life of more than 3 years.
Future technology development trends
Intelligent monitoring: integrating sensors and AI algorithms to optimize catalyst working conditions in real time;
Multifunctional materials: developing perovskite catalysts to simultaneously treat CO, NOx and VOCs;
Circular economy model: promoting the concept of "production process coupling", such as chemical companies and energy companies coordinating the disposal of waste gas to reduce the cost of treatment.
Conclusion
Industrial waste gas treatment needs to combine technological innovation with systematic strategies. The application of high-efficiency catalytic materials such as hopcalite has significantly improved the treatment efficiency. In the future, through material innovation and industrial collaboration, waste gas treatment will move towards a more sustainable development model with lower carbon and lower cost.