Activated carbon delivery scheme
Material properties
Activated carbon is a specially treated carbon that heats organic raw materials (nut shells, coal, wood, etc.) in the absence of air to reduce non-carbon components (this process is called carbonization), and then reacts with the gas, and the surface is covered with air. Erosion, resulting in a microporous structure (this process is called activation). Since the activation process is a microscopic process, that is, the surface erosion of a large number of molecular carbides is point erosion, so the activated carbon surface has numerous tiny pores. Most of the micropore diameters on the surface of activated carbon are between 2 and 50 nm. Even a small amount of activated carbon has a huge surface area. The surface area of each gram of activated carbon is 500 to 1500 m2. Almost all applications of activated carbon are based on this feature of activated carbon.
Production problems
1. Activated carbon treatment is an advanced treatment process, which is usually only considered when the individual water quality indicators of the effluent still cannot meet the discharge requirements after the wastewater has been treated by other conventional processes.
2. Before deciding to select the activated carbon process, the effluent of the previous treatment process or the water samples with similar water quality should be used for carbon column test, and the activated carbon of different brands and specifications should be screened, and then the main design parameters, such as water filtration, should be obtained through the test. speed, effluent quality, saturation cycle, short backwash cycle, etc.
3. The influent water of the activated carbon process should be filtered first to prevent the surface of the carbon layer from being blocked due to a large amount of suspended solids. At the same time, the concentration of organic matter in the influent water should not be too high to avoid excessive saturation of activated carbon, so as to ensure a reasonable regeneration cycle and operating cost. When the CODc concentration of the influent water exceeds 50-80 mg/L, the biological activated carbon process should generally be considered for treatment.
4. For reclaimed water treatment or some treatment processes where the concentration of pollutants exceeding the standard frequently changes, the activated carbon treatment unit should be equipped with a spanning or bypass pipe. Activated carbon unit, which can save the adsorption capacity of the activated carbon bed and effectively prolong the regeneration or replacement cycle.
5. When using a fixed bed, consider designing a spare pool or carbon tower according to the regeneration or replacement cycle of activated carbon. Mobile beds should also be considered for backup when necessary.
6. Since the contact between activated carbon and ordinary steel will cause serious electrochemical corrosion, the reinforced concrete structure or stainless steel, plastic and other materials should be considered first when designing the activated carbon treatment device. If ordinary carbon steel is used, the inner surface of the device should be lined with epoxy resin, and the thickness of the lining should be greater than 1.5mm.
7. When using powder activated carbon, consider fire and explosion protection, and the electrical equipment used also meets explosion-proof requirements.
Use equipment
Vacuum feeder (because the activated carbon powder is fine, the material and fineness of the filter element need to be considered).
