Activated Carbon for Wastewater

Activated carbon is a material with a highly porous structure and adsorption capacity and is widely used in the field of sewage treatment. It can effectively remove organic matter, heavy metals, chloride and other pollutants in water, and improve the purification effect of water quality.

This blog presents the wastewater sources, the detailed application of activated carbon in water treatment, and activated carbon types.

What kind of water pollution is activated carbon used for?

Activated carbon plays a crucial role in water treatment across various sectors, including sewage treatment plants, industrial wastewater treatment, and domestic sewage treatment. It effectively removes pollutants such as organic matter, heavy metals, and suspended solids, improving treatment efficacy and enhancing water quality in each application.

Sewage treatment plant

Activated carbon is often used in the secondary treatment process of sewage treatment plants. By adding it to the adsorption tank or filter of the sewage treatment system, it can effectively remove organic matter, heavy metals and other pollutants in the sewage, thereby improving the treatment effect.

Industrial wastewater treatment

Industrial wastewater treatment is also one of the areas where activated carbon is widely applied. Different types of industrial wastewater contain various pollutants. By selecting appropriate activated carbon materials, pollutants in industrial wastewater can be removed to meet environmental protection requirements.

Domestic sewage treatment

Activated carbon can also be used in domestic sewage treatment. By adding activated carbon to the secondary sedimentation tank or filter in the domestic sewage treatment system, suspended solids, grease, odors, etc. in the sewage can be removed, improving the treatment effect of domestic sewage and purifying water quality.

What is the role of activated carbon in wastewater treatment?

In wastewater treatment, activated carbon is mainly used to remove heavy metal ions, organic matter and color from wastewater, and can be applied for various fields such as domestic, industrial, pharmaceutical, printing and dyeing, textile, and food.

Removing organic matter

Activated carbon has strong adsorption capacity and can effectively remove organic matter in sewage. Organic matter is one of the main pollutants in sewage, including suspended solids, grease, protein, etc. By adding activated carbon to the sewage treatment system, it can absorb organic matter, reduce turbidity in the water, and improve the purification effect of water quality.

Removing color

The color in wastewater is mainly caused by organic matter. Activated carbon can also remove color in wastewater treatment through its ability to absorb organic matter. When the quality of activated carbon adsorbed organic matter reaches a certain amount, the color can also be significantly reduced.

Removing chloride

Activated carbon can also remove chloride from water. Chloride is one of the common pollutants in sewage, mainly coming from bleaches and disinfectants in industrial wastewater and domestic sewage. Chloride in water can form harmful substances such as hypochlorite and chloroform. By adding activated carbon to the sewage treatment system, chloride can be adsorbed and its impact on water quality reduced.

Removing heavy metals

Activated carbon has strong adsorption capacity for heavy metal ions. Heavy metals are one of the common pollutants in sewage, such as lead, chromium, mercury, etc. These heavy metal ions have certain toxicity to the human body and the environment. By adding activated carbon to the sewage treatment system, heavy metal ions can be adsorbed and their concentration reduced to achieve the purpose of purifying water quality.

Activated carbon types

In wastewater treatment, both granular activated carbon (GAC) and powdered activated carbon (PAC) are extensively employed for purification purposes. GAC, comprising larger particles, is often utilized in fixed-bed filters or packed media systems, allowing for efficient removal of contaminants as water flows through. Conversely, PAC, consisting of fine particles, offers high surface area per unit volume, facilitating rapid adsorption of pollutants when mixed directly with water. These two forms of activated carbon play pivotal roles in addressing diverse water quality challenges across various treatment applications, ensuring the effective removal of organic compounds, chemicals, and other contaminants to meet stringent purification standards.

Powder activated carbon (PAC)

Powdered activated carbon consists of very fine particles, typically with a particle size ranging from less than 0.18 mm down to submicron sizes. Due to its small particle size, it only requires shorter contact times with water to achieve effective contaminant removal. This makes PAC well-suited for applications where rapid adsorption is desired, such as batch treatment processes or systems with limited contact time.

Powdered activated carbon is commonly used in batch treatment processes, such as in mixers or reactors, where it can be added directly to water to remove contaminants. PAC is also used in some continuous treatment systems, although it may require additional separation steps, such as filtration or sedimentation, to remove the carbon particles from treated water.

Granular activated carbon (GAC)

Granular activated carbon, on the other hand, comprises larger particles, usually ranging from 0.2 to 5 mm in diameter. It requires longer contact times with water to achieve optimal adsorption due to its larger particle size. However, GAC offers the advantage of better hydraulic characteristics, allowing for more efficient flow through fixed-bed filters and continuous treatment systems.

Granular activated carbon is widely used in fixed-bed filters, where water flows through a bed of GAC to remove contaminants. GAC can also be used in fluidized bed reactors or as a packed media in columns for continuous treatment applications. Its larger particle size allows for easier handling and regeneration in certain systems.

Conclusion

Activated carbons have been proved to be an important material in wastewater treatment. Whether in municipal sewage treatment plants, industrial wastewater treatment, or household sewage treatment, activated carbon has demonstrated its high performance in removing organic matter, heavy metals, chlorides, and other pollutants. By selecting the appropriate activated carbon type, such as powdered activated carbon (PAC) and granular activated carbon (GAC), customized solutions can be provided for different water quality challenges.

Zhulin Carbon is committed to providing high-quality activated carbon products to support global wastewater treatment and environmental protection efforts. Contact our technical experts today for a customized activated carbon solution for your specific wastewater treatment