Activated carbon deodorization

activated charcoalAdsorption technology has been used for refining and decolorization in industries such as pharmaceuticals, chemicals, and food in China for many years. It has been used for industrial wastewater treatment since the 1970s. Activated carbon adsorption has gradually become one of the main methods for odor treatment.

Activated carbon is a type of very small carbon particle with a large surface area, and there are even smaller pores - capillaries - in the carbon particles. This type of capillary has strong adsorption capacity, and due to the large surface area of carbon particles, it can fully contact with gases (impurities). When these gases (impurities) come into contact with capillaries and are adsorbed, they have a purifying effect.

Adsorption is a slow process in which a substance adheres to the surface of another substance. Adsorption is an interfacial phenomenon that is related to changes in surface tension and surface energy. The specific surface area and pore structure of activated carbon directly affect its adsorption capacity. When selecting activated carbon, it should be determined through experiments based on the properties of the exhaust gas. In addition, ash content also has an impact, the smaller the ash content, the better the adsorption performance; The closer the size of adsorbate molecules is to the pore diameter of carbon, the easier it is to be adsorbed; The concentration of adsorbate also has an impact on the adsorption capacity of activated carbon. Within a certain concentration range, the adsorption capacity increases with the increase of adsorbate concentration. In addition, temperature and pH value also have an impact. The adsorption capacity decreases with increasing temperature and increases with decreasing pH value. Therefore, low temperature and low pH value are beneficial for the adsorption of activated carbon.

In order to effectively remove odor, various types of activated carbon with different properties are usually used. Activated carbon that adsorbs acidic substances, activated carbon that adsorbs alkaline substances, and activated carbon that adsorbs neutral substances are installed in the adsorption tower. After the odor comes into contact with various activated carbons, it is discharged from the adsorption tower.

Characteristics of Activated Carbon Deodorization:

1) The reaction is thorough and can almost completely remove volatile organic compounds from the exhaust gas;

2) According to the type of exhaust gas, the corresponding adsorbent can be selected. At present, commonly used adsorbents include activated carbon, activated carbon fiber, silica gel, diatomaceous earth, activated alumina, synthetic zeolite, etc;

3) For small and difficult to treat waste gas components such as polychlorinated biphenyls, impregnation adsorbents such as potassium permanganate impregnated carbon can be used to achieve thorough purification;

4) The adsorption and regeneration cycle of activated carbon is relatively short;

5) Small footprint;