What is anthracite media?

Properties of anthracite filter media

filter media is a material commonly used in water treatment and filtration processes. Its main properties are as follows:

Chemical stability: anthracite filter media has good chemical stability, is not easy to react with chemicals in water, and is suitable for various water quality conditions.

High mechanical strength: anthracite filter media has a large hardness and high compressive strength. It is not easy to break during the filtration process and can ensure the filtration effect.Porosity: anthracite filter media has a developed pore structure, which helps to improve the filtration efficiency and effectively remove suspended matter and particles when water flows through.

Density: The density of anthracite media is generally between 1.4-1.6 g/cm³, which is larger than other types of filter media.

Adsorption: anthracite media has a certain adsorption capacity and can remove organic matter, pigments and odors in water.

Low wear rate: anthracite filter media has a low wear rate during the filtration process and a relatively long service life.

Easy to clean: Due to its smooth surface, anthracite filter media is easy to clean during backwashing and can restore filtration efficiency.

Environmental protection: Anthracite filter material is a natural material, which can be naturally degraded after use and is environmentally friendly.

Diverse specifications: Anthracite filter material can be made into different particle sizes according to different filtration requirements to meet the needs of different processes.

Anthracite filter material is widely used in water treatment, air purification, chemical industry, food and other industries. When using, the filter material of appropriate specifications should be selected according to the specific process requirements and water quality conditions, and backwash maintenance should be performed regularly to ensure the normal operation of the filtration system.

2. How to choose the filter particle size of anthracite

Choosing the appropriate anthracite filter particle size is one of the key factors to ensure the effective operation of the filtration system. The following are some factors that should be considered when choosing the particle size of anthracite filter material:

Purpose of filtration: First, clarify the purpose of filtration, such as whether it is used for rapid filtration, fine filtration or deep filtration.

Water quality requirements: According to the water quality of the raw water, including the size and concentration of suspended matter and other pollutants that may be contained.

Filtration speed: The filtration speed will affect the selection of the filter particle size. Generally speaking, the faster the filtration speed, the larger the particle size of the filter material needs to be used.

Here are some specific steps and guidelines:

Determine water quality analysis and suspended solids particle size distribution: Understand the particle size distribution of suspended solids in the water through the water quality analysis report, and select the filter media particle size that can effectively intercept these suspended solids.

Reference filtration process: According to the existing filtration process or design requirements, select the appropriate filter media particle size. For example, in a multi-layer filtration design, the upper layer usually uses a coarser filter media, while the lower layer uses a finer filter media.

Follow the filter media grading principle: It is usually recommended to use multi-layer graded filter media, that is, the filter media is stacked from coarse to fine, which can improve the filtration efficiency and extend the backwash cycle.

Consider the type and structure of the filter: Different types of filters (such as pressure filters, gravity filters, rapid filters, etc.) have different requirements for filter media particle size.

The selection of specific particle size can refer to the following guidelines:

Coarse filtration: If the purpose is to remove larger suspended solids and particles, you can choose anthracite filter media with a particle size of 1.0-2.0mm or larger.

Conventional filtration: For general water treatment, you can choose anthracite filter media with a particle size of 0.5-1.0mm.

Fine filtration: If you need to remove smaller suspended solids, you can choose anthracite filter media with a particle size of 0.3-0.5mm.

Deep filtration: For occasions where deep filtration is required, you can choose filter media with finer particle sizes, such as 0.1-0.3mm.

Finally, it is recommended to conduct a small-scale filtration test before actual application to verify whether the selected filter media particle size meets the expected filtration effect. Through the test, the selection of filter media can be adjusted and optimized to ensure the stability and efficiency of the filtration system.

3. How to use double-layer filter media anthracite and quartz sand together

Anthracite and quartz sand are both commonly used water treatment filter media. They are usually used together in multi-layer filter media filtration systems to improve filtration efficiency and water quality treatment effects. The following are some guidelines for how to use anthracite and quartz sand together:

Layered design:

Bottom layer (support layer): Quartz sand is usually used as the bottom layer because it has high density and mechanical strength, and can support the upper filter material to prevent the filter material layer from moving or losing.

Middle layer (transition layer): Anthracite filter material with slightly larger particle size can be placed to play a transitional role and help intercept larger suspended matter.

Top layer (fine filtration layer): Anthracite filter material with smaller particle size is used for fine filtration to remove smaller suspended matter and some organic matter.

Particle size gradation:

From bottom to top, the particle size of the filter material should gradually decrease to form a natural particle size gradation. The quartz sand particle size of the bottom layer is the largest, and the anthracite particle size of the top layer is the smallest.

This gradation ensures that during filtration, larger particles are first intercepted by the bottom layer, while smaller particles are gradually removed by the upper filter material.

Filter material thickness:

The thickness of each layer of filter material should be determined according to the size of the filter, the expected filtration rate, and the amount of water to be treated.

Generally, the quartz sand layer is thicker because it mainly plays a physical interception role; the anthracite layer can be relatively thin because it mainly plays the role of adsorption and fine filtration.

Backwashing:

During the backwashing process, since the density of anthracite is less than that of quartz sand, attention should be paid to the intensity and method of backwashing to prevent the anthracite layer from mixing or loss.

When backwashing, it should start from the top layer and gradually move to the lower layer to maintain the gradation of the filter material.

Water quality requirements:

According to the water quality of the raw water and the water quality requirements after treatment, adjust the ratio and particle size of anthracite and quartz sand to achieve the best filtration effect.

Operation management:

Regularly monitor the filtration effect and adjust the filter material gradation and backwashing strategy according to the changes in water quality.

Pay attention to the wear of the filter material and replenish or replace the filter material in time.

Through the above-mentioned method of using anthracite and quartz sand together, an efficient and stable multi-layer filter material filtration system can be constructed to effectively remove suspended matter, organic matter and other impurities in the water and ensure the effect of water treatment.

4. How does anthracite of different particle sizes affect the filtration effect

The influence of anthracite filter materials of different particle sizes on the filtration effect is mainly reflected in the following aspects:

Filtration accuracy:

Fine-grained anthracite media: It can intercept smaller suspended particles, provide higher filtration accuracy, and is suitable for fine filtration.

Coarse-grained anthracite: It is mainly used to intercept larger particles, with relatively low filtration accuracy, suitable for coarse filtration or pre-filtration.

Filtration speed:

Coarse-grained anthracite: Due to the large pores, the speed at which water flows through can be relatively fast, so the filtration speed is high.

Fine-grained anthracite: The pores are small, the speed at which water flows through is slow, and the filtration speed is low.

Filtration resistance:

Coarse-grained anthracite: The water flow resistance is small and the energy consumption is relatively low.

Fine-grained anthracite: The water flow resistance is large, which may lead to increased energy consumption.

Backwash effect:

Coarse-grained anthracite: Due to the large particles, it is easy to clean during backwashing, and the backwashing effect is good.

Fine-grained anthracite: The particles are small and easy to clog. Higher water pressure and longer flushing time may be required to achieve a cleaning effect during backwashing.

Filter layer pressure drop:

Coarse-grained anthracite: The filter layer formed has a small pressure drop, which is conducive to maintaining stable filtering operation.

Fine-grained anthracite: The filter layer has a large pressure drop, and more frequent backwashing may be required to maintain the filtering effect.

Life of the filter layer:

Coarse-grained anthracite: Due to the large particles and good wear resistance, the life of the filter layer is relatively long.

Fine-grained anthracite: The particles are small and the wear resistance is poor, and more frequent replacement may be required.

Processing capacity:

Coarse-grained anthracite: It is suitable for treating water with a high content of suspended matter because its pores are large and not easy to clog.

Fine-particle anthracite: Suitable for water with low suspended matter content, it can provide finer filtration.

Adaptability:

Anthracite filter media of different particle sizes can be used in combination to form a multi-layer filter media structure to adapt to different water quality and treatment requirements.

In summary, choosing anthracite filter media of appropriate particle size is crucial for the filtration effect. In practical applications, anthracite filter media of different particle sizes should be reasonably selected and matched according to the specific water quality conditions, treatment goals and process requirements to achieve the best filtration effect and system operation efficiency.

5. Thickness ratio of anthracite and quartz sand in double-layer filter media

In the multi-layer filter media filtration system, there is no fixed standard for the thickness ratio of anthracite and quartz sand, because it depends on many factors, including the specific requirements of the filtration process, the quality of the raw water, the expected filtration effect, the filter media particle size grading, the type and size of the filter, etc. The following are some common ratio ranges and considerations:

Conventional ratio:

Generally, the thickness of the quartz sand layer (bottom layer) may be greater than the thickness of the anthracite layer (middle or top layer). A common ratio range may be quartz sand: anthracite = 2:1 to 3:1.

For example, if the quartz sand layer is 1 meter thick, the anthracite layer may be between 0.3 and 0.5 meters thick.

Considerations:

Purpose of filtration: If the main purpose of filtration is to remove larger suspended matter, the quartz sand layer may be thicker; if fine filtration is required, the anthracite layer may be relatively thicker.

Water quality characteristics: The particle size distribution of suspended matter in the raw water will also affect the thickness ratio of the filter layer. If the suspended matter particle size is larger, the quartz sand layer can be thicker; otherwise, the anthracite layer can be appropriately thickened.

Filter particle size: Coarse particle size filter layers are usually thicker than fine particle size filter layers because they can withstand greater water flow impact and suspended matter load.

Filtration rate: A higher filtration rate may require a thicker quartz sand layer to prevent filter media loss, while a lower filtration rate can allow a relatively thick anthracite layer.

Practical application:

In actual design, a small-scale filtration test is usually required to determine the best ratio to ensure that the filtration system achieves the expected performance.

Designers and engineers will make adjustments based on specific circumstances and may refer to historical data and experience of similar processes.

In short, the thickness ratio of anthracite and quartz sand needs to be optimized according to specific circumstances. It is recommended to consult a professional water treatment engineer or refer to relevant industry standards and manuals to determine the ratio suitable for a specific application when designing a filtration system.