Water filter media

Types of water filter media

Water filter media is an integral part of any water filtration system, providing the surface and the optimum environment for the effective physical, chemical, and biological processes involved in removing impurities and contaminants of water.

• Sand: Under the force of gravity, sand filters carry out the separation of impurities and pollutants. Sand filters are often the main elements of water treatment and purification plants around the globe. In addition to this, the use of sand as water filter media is also widespread in private facilities. Pools are the most common pools. The sand retains particles that are invisible to the naked eye, which is, in most cases, bacteria. Sand particles are typically angular to promote better particle retention and rigidity, which encourages rearrangement during filtration. Quartz is the most common type of sand used in sand filters, as it possesses the properties needed for sand filtration.
• Gravel: Gravel filters can be permanent or temporary parts of a water treatment process. They are widespread but are typically used as a pretreatment barrier for sand or other filters. Gravel easily allows water to pass through. At the same time, it effectively retains larger particles such as sand, leaves, and other organic matter, which can, in some cases, clog other filters.
• Activated carbon: Water filter activated carbons have a massive porous structure, which provides an enormous surface area, offering a broad variety of adsorption possibilities. They effectively eliminate biological impurities such as organic matter, chlorine, and microorganisms by the process of microbial degradation. They are commonly used in municipal water treatment facilities and domestic appliances.
• Zeolite: Zeolite is a natural or synthetic hydrated aluminosilicate mineral that usually contains alkaline or alkaline earth metal cations. Zeolite filters, which can be found both as individual filters and as additives to other types of filters, can filter out specific heavy metals like lead and copper and ammonium nitrogen.
• Anthracite: Anthracite filters, like sand filters, are usually a part of water treatment plants in reservoirs and are considered the best solution for eliminating pathogens and organic matters.
• Multi-media filters: Multi-media water filter media typically consist of anthracite, sand, and gravel. Sometimes, other types of filter media, such as activated carbon, will be added to anthracite and sand. Multi-media filters significantly reduce filtration time when compared to mono-media filters.
• Synthetic filter media: With the continuous development of polymer synthesis technology, polymer-based water filter media, such as polypropylene, polyester, polyamide, etc., have appeared in the water treatment market. They mainly carry out microfiltration and ultrafiltration and play an essential role in separating larger quantities of water.

Specification & Maintenance

A proper water filter media performs its function based on the following specifications:

• Surface Area

  The total surface area available for filtration affects the flow rate and quality of the filtered water. Water filter sands have different sizes of particles. The smaller particles create more surface area, but they reduce the flow rate.

• Porosity

  The percentage of empty spaces in the media impacts the retention of contaminants. High porosity media can hold more particles but might get saturated faster.

• Retention Capacity

  This is the amount of contaminants water filter media can retain before it needs cleaning or replacement. Loading up to 30% of its capacity is efficient. If the media retains more than 30%, it will have to be cleaned or replaced.

• Storage and Shipping

  Water filter media storage and shipping is important so that customers get the product in a good state. During storage, the product should not get wet. When transporting it, cover the bulk bags with tarps.

Maintenance of Water Filter Media

Water filter media needs cleaning on a periodic basis so that the quality of water remains good. Water filtration systems flush out contaminants and then send clean water back into the system. Flushing is not enough. Vacuuming or air scouring is also necessary to remove settled or attached particles that do not leave the system by flushing alone.

Dust and dirt enter the water media filter and settle in different sections of the filter. Flushing out water does not remove all types of pollutants. Some contaminants remain inside the filter and do not leave even after flushing. Air scour or vacuuming can remove these settled contaminants.

Post backwashing of water filter media, the system performs better because of improved flow rates, filtrations efficiency and drain times. The tasks also extend the life of the filter media as it helps to maintain its integrity. Flushing out the system also helps in the even distribution of water across the surface of the filter.

Backwashing of the water filter media is important to flush out waste from the system. During the process, water moves in the reverse direction, flushing out suspended particles and debris. Using air in the process enhances the cleaning process as it lifts the debris to the surface, letting it to be washed away easily.

Backwashing has other benefits. It helps to prevent the formation of biofilm or any kind of organic matter that can decay inside the media. The organic matter not only damages the media but could also cause damage to the health of people using the filtered water.

Scenarios of water filter media

Water filter media is widely used in various fields to develop and maintain a sustainable society and environment.

• Municipal water treatment

  Water filter media is an essential part of the municipal water treatment plant. It is installed in the filtration system to clean the drinking water for the whole city. Using different kinds of water filter media at different stages can help deal with various kinds of impurities to guarantee that the water residents get is safe and protects their health.

• Industrial wastewater treatment

  Industries usually use water filter media to deal with their wastewater. By using these media, factories can ensure that their wastewater is properly processed, and the environment is not harmed. Additionally, the treated water can be reused inside the factory through this process, thus greatly reducing the industry's water consumption.

• Global water crisis solution

  In some parts of the world that are struggling with a shortage of water resources, such as arid areas, desert regions, or island countries, water filter media still play an essential role. They are often used inside rainwater harvesting systems or desalination devices. By using water filter media, the limited water resources can be effectively utilized, greatly alleviating the pressure on regional water supply.

• Aquarium filtration

  Water filter media also play an important role in maintaining life in aquariums. Regardless of whether it is a home-based aquarium or a public display aquarium, these media can ensure that the fish live in a clean and suitable environment.

• Hydroponics and recirculating aquaculture systems

  Water filter media also play an important role in recirculating aquaculture systems and hydroponic systems. They ensure that the nutrient solution and water carefully preserve valuable components to maintain the stable operation of the system.

• Food industry

  Food and beverage manufacturing companies usually have to comply with strict standards in terms of purity and quality. Thus, the water filter media is used in the production process to make sure that everything from raw materials to final products is well-filtered water, thereby guaranteeing the safety and quality of the products.

How to choose water filter media

• Source:

  Whether natural or manufactured, each water filter media source has distinct benefits and levels of pollution removal capacity. For instance, sand, a natural media, is quite effective at removing specific contaminants due to its widespread use in diverse geographic areas. On the other hand, synthetic media like anthracite might offer more uniform filtration characteristics, making them suitable for particular applications.

• Contaminant removal:

  It's essential to match the media's removal capabilities with the specific contaminants present in the source water. For instance, while activated carbon excels at removing organic compounds and chlorine, sand primarily captures larger sediments and particles.

• Filtration rate:

  The speed at which water passes through the filter, known as the filtration rate, can influence the effectiveness of filtration. High rates might cause media disruption, leading to reduced filtration efficiency. It's vital to maintain optimal filtration rates for each media type to ensure proper functioning and contaminant removal.

• Compatibility with existing systems:

  When selecting water filter media, it's essential to ensure that the chosen media is compatible with current filtration systems. Whether installing a new filter or upgrading the existing one, the selected filter media should work effectively with the existing setup to ensure optimal performance.

• Cost:

  Although the initial media purchase cost is vital, it's equally crucial to factor in long-term expenses like maintenance, replacement, and potential system upgrades. Some filter media might be cheaper initially but require more frequent replacements or incur higher maintenance costs.

FAQ

Q1: Can filter media remove dissolved solids in water?

A1: Generally, filter media can only remove suspended solids and some large molecules through physical straining. Activated carbon can remove some chemicals through absorption. To remove dissolved solids, one needs to use ion-exchange resins.

Q2: What is the life span of water filter media?

A2: It depends on the type. For sand and gravel, the life span can be several years. Activated carbon has a life span of 6 months to 2 years. Ceramic media can last up to 5 years. Synthetic polymer media can last up to 10 years. Plastic media has an indefinite life span.

Q3: Can water filter media be reused?

A3: Some filter media, such as activated carbon and sand, can be cleaned and reused. Others, like activated carbon, ceramic, and plastic media, can be used repeatedly but are not cleaning easily.