Brasil
China
Germany
India
JapanNo matter your application, De Nora has the filtration solution for you. Common municipal applications include filtration of drinking water, pre-treatment of seawater for desalination, and tertiary treatment of wastewater. Industrial applications include both gravity and pressure filtration, with a focus on steel industry applications that require removal of high concentrations of oil and grease and mill scale solids.
DE NORA TETRA® Filter Underdrain
De Nora has more than 50 years of experience and > 1,300 installations providing media filtration solutions to both municipal and industrial markets. A variety of filtration products allows De Nora to customize filter design for optimal performance in a particular application. Common municipal applications include pre-treatment of seawater for desalination, filtration of drinking water sources, and tertiary treatment of wastewater. Industrial applications include both gravity and pressure filtration, with a focus on steel industry applications that require removal of high concentrations of oil and grease and mill scale solids.
Easy to Operate and Maintain
Cost Saving
Reliability / Equipment Longevity
Low Profile Designs
Why DE NORA TETRA filter underdrains?
For municipal drinking water, desalination pre-treatment and wastewater applications where plants use gravity filters, the filter underdrain is one of the most important components contributing to overall system performance and operation — whether a new filter design or retrofitting an existing filter.
Drinking water
Dual parallel lateral underdrain products including DE NORA TETRA U, LP, and Anchor-Rite® Blocks are ideal for common applications such as drinking water treatment and other pretreated water sources.
History of proven performance:
- Excellent distribution of backwash air and water keeps filter media clean
- Suitable to retrofit any air / water backwash scheme
- Low profile for better filtration performance and longer filter runs
- Reliably strong resistance to underdrain uplift pressure
- Low operating costs and minimal maintenance
Wastewater filtration
DE NORA TETRA SNAP T® Block filter underdrains provide a unique non-clogging underdrain for heavily loaded wastewater applications. Even water sources with oils, grease and mill scale solids can be effectively treated with this underdrain.
- Media selection can be customized to further fine-tune filter performance
- Excellent distribution of backwash air and water for efficient bed cleaning and low filter operating costs
- New or retrofit applications are ideal candidates
- Simple to install
- Minimal maintenance, no moving parts
Want to learn more about our DE NORA TETRA® Media Filtration Solutions?
How do DE NORA TETRA filter underdrains work?
DE NORA TETRA filter underdrain technology is a key component of water treatment and filtration systems, and it primarily serves to support the filtration process by providing a stable and efficient foundation for filter media. Here's how it works:
1. Filter Bed: In water treatment, a filter bed is a layer of granular filter media, such as sand, anthracite, or activated carbon, through which water passes. This filter bed traps and removes impurities, suspended particles, and contaminants from the water. The filter bed is typically housed in a filtration tank or vessel.
2. DE NORA TETRA filter underdrain system: The DE NORA TETRA filter underdrain consists of a series of plastic blocks that are placed in rows along the bottom of the filter bed to form a floor for the filter to support the media. DE NORA TETRA blocks have a unique and carefully engineered design that offer.
- Even Distribution: The design of the DE NORA TETRA filter underdrain ensures the even distribution of water throughout the filter bed. It helps prevent channelling or uneven flow that can occur in traditional filter systems, which can lead to poor filtration efficiency.
- Durability and Longevity: DE NORA TETRA underdrain systems are known for their robust construction and long lifespan. They are resistant to corrosion and other environmental factors, making them suitable for various water treatment applications.
Rapid Gravity Filtration: Rapid gravity filtration is a common water treatment process that relies on gravity to push water through the filter bed. Here's how it works:
- 1. Inlet: Contaminated water is introduced into the filtration tank, where it enters from the top and flows downward through the filter bed.
- 2. Filter Bed: As water passes through the filter bed, suspended particles and impurities are trapped by the filter media. The filter bed effectively acts as a physical barrier, removing impurities from the water.
- 3. DE NORA TETRA filter underdrain: The DE NORA TETRA filter underdrain system plays a crucial role in this process. It evenly distributes the water throughout the filter bed, ensuring that every part of the bed is involved in the filtration process. This uniform flow helps optimize the filtration efficiency.
- 4. Outlet: Clean, filtered water exits the filter bed at the bottom and is collected for further treatment or distribution to consumers.
In summary, the DE NORA TETRA underdrain technology enhances the performance of water treatment systems by providing even water distribution through the filter bed, ensuring efficient removal of impurities and contaminants. Rapid gravity filtration is just one of the applications where this technology is beneficial, and it contributes to the durability and longevity of water treatment processes.
Applications
