Activated Carbon Filter: Introduction to the Filtration Rate of Activated Carbon Filters

What is the filtration rate of an activated carbon filter?

When the solid particles in a suspension are relatively large and uniformly sized, the pore structure of the filter cake is smoother, allowing the filtrate to pass through the cake more rapidly. The addition of a coagulant to aggregate fine particles into larger flocs can further enhance the filtration rate. For suspensions in which solid particles settle quickly, activated carbon filters can be used by placing a layer of filter aid on the filtration medium, aligning the filtration direction with the direction of gravity so that coarse particles settle first, thereby reducing clogging of the filtration medium and the filter cake. In difficult-to-filter suspensions, such as colloids, the incorporation of coarse solid particles like diatomaceous earth or expanded perlite can loosen the filter cake. When the filtrate has high viscosity, heating the suspension can reduce its viscosity. All these measures can accelerate the filtration process.

What are the performance characteristics of an activated carbon filter?

1. High-efficiency, high-accuracy filtration: This is a specially designed filtration technology that delivers precise and highly sensitive performance. Only particles smaller than the specified size can pass through the system, making it an effective filtration solution. Available specifications include 5, 10, 20, 55, 100, 130, and 200 microns; users can select filter discs with different levels of precision based on their water quality requirements. System flow rate can be flexibly adjusted as needed.

2. Standardized, modular design that saves space: The system is designed in a modular fashion based on standard disk-filter equipment, offering selection, flexibility, and interchangeability to meet specific needs. With a compact footprint and minimal space requirements, it can be flexibly installed in edge spaces; for example, a unit with a processing capacity of approximately 300 m³/h occupies about 6 square meters (under typical water quality conditions and with a filtration rating of 100).

3. Fully automated operation with continuous water production: The individual modules in the filter train alternate between filtration and backwashing, automatically switching between operating and backwash modes to ensure uninterrupted water supply. Backwash water consumption is minimal, accounting for only 0.5% of the total water volume. When combined with air-assisted backwashing, on-site water usage can be reduced to below 0.2%. The high-speed, thorough backwashing cycle can be completed in just a few tens of seconds.

4. Long service life: The new plastic filter elements are robust, wear-free, corrosion-resistant, and virtually free of fouling. Extensive industrial field trials have demonstrated that they remain undamaged and do not degrade over 6 to 10 years, with filtration and backwashing performance consistently maintained without deterioration over time.

5. High quality with minimal maintenance: The products meet the relevant quality standards, and each unit undergoes simulated operational-condition testing and commissioning before leaving the factory. No specialized tools are required, and the number of components is kept to a minimum. Ease of use means only periodic inspections are needed; routine daily maintenance is virtually unnecessary.

Suspension-type activated carbon filters employ three filtration methods: surface filtration, depth filtration, and adsorption.

1. Cake filtration: In the early days, filter media could only retain large solid particles, while fine particles passed through the medium along with the filtrate. Once an initial filter cake had formed, the cake itself became the primary filtering element, effectively removing both large and small particles (as in plate-and-frame filter presses).

2. Depth filtration: The filter medium is thick, the suspension contains few solid particles, and the particle size is smaller than the pores of the filter medium. During filtration, particles are adsorbed within the pores (e.g., in porous plastic pipe filters and sand filters). Screen filtration: In this method, the solid particles to be removed are larger than the pores of the filter medium, so no solid particles are adsorbed inside the medium. For example, rotary filters are used to remove coarse impurities from wastewater. In practical filtration processes, these three methods often occur simultaneously or sequentially.