De Nora
De Nora at Siewert Equipment & F.R. Mahony
Filtration & Disinfection Technologies for Clean Water & Sustainable Treatment
As a global leader in water and wastewater treatment, De Nora offers a comprehensive portfolio of technologies that protect public health and support environmental sustainability. From TETRA™ media filters and biological treatment systems to UV disinfection and PFAS removal, De Nora provides proven, innovative solutions for both municipal and industrial systems.
Available through Siewert Equipment in Upstate New York and F.R. Mahony in New England, De Nora’s technologies support everything from drinking water filtration and arsenic removal to tertiary wastewater treatment and advanced oxidation.
Engineered for Performance & Protection
De Nora’s filtration and disinfection systems are designed for flexibility, scalability, and
regulatory compliance. Whether your goal is nutrient removal, PFAS treatment, or microbial disinfection, De Nora delivers efficient, low-maintenance, and cost-effective technologies built for long-term success.
With decades of field-proven performance and support from trusted regional partners, De Nora systems are a smart investment in public health and water quality.
Industries & Applications
- Municipal Drinking Water
- Municipal Wastewater Treatment
- Groundwater Remediation
- Industrial Water Reuse
- Nutrient Removal
- PFAS & Emerging Contaminant Removal
- Surface Water Filtration
- Disinfection & Advanced Oxidation
Why Choose De Nora from Siewert or F.R. Mahony?
- Authorized De Nora representatives in NY & New England
- Deep application knowledge in filtration and disinfection
- Full-service support from system design to startup
- Local engineering and technical field services
- Reliable inventory and aftermarket assistance
De Nora Product Offerings
TETRA™ Water Filter LP® & U Block®
- Underdrain systems for gravity filtration
- Even air and water distribution for consistent filter performance
- Ideal for municipal drinking water filtration and pre-treatment
TETRA™ Wastewater Filters
- Low-energy, dual-parallel lateral filter blocks
- Excellent for secondary and tertiary filtration
- Reduces suspended solids, BOD, and phosphorus
TETRA™ DeepBed™ & Denite® Filters
- Granular media deep bed filters for tertiary treatment
- Denite® systems for biological denitrification
- Compliant with low TN and phosphorus discharge limits
TETRA™ SAF® – Submerged Aerated Filters
- Fixed-film biological treatment for BOD and ammonia removal
- Space-saving, energy-efficient nitrification
- Used in secondary and tertiary wastewater applications
TETRA™ ColOX® – Biological Wastewater Filters
- Aerated biofilters for organic and nitrogen removal
- Treats municipal and industrial wastewater
- High-rate performance with compact footprint
SORB™ Adsorptive Media Systems
- Targeted removal of arsenic, nitrate, and fluoride
- NSF-certified media options
- Designed for safe, reliable contaminant reduction
PFAS Treatment Technologies
- Ion exchange systems for PFAS and emerging contaminant removal
- High selectivity and long media life
- Adaptable to new MCLs and evolving regulations
UV Disinfection & AOP (Formerly Calgon Carbon)
- Closed-vessel and open-channel UV disinfection
- UV Advanced Oxidation for trace organic and micropollutant destruction
- Proven in drinking water and reuse applications
What Is UV Advanced Oxidation (AOP)?
UV AOP is a cutting-edge treatment that combines ultraviolet light with hydrogen peroxide or other oxidants to destroy contaminants at the molecular level. De Nora’s AOP systems break down hard-to-remove compounds like 1,4-dioxane, taste & odor compounds, and pharmaceutical residues—offering utilities a future-ready solution for compliance and water safety.
Full-Service Support from Siewert & F.R. Mahony
✔ System evaluation and process recommendations
✔ Pilot testing and performance modeling
✔ Equipment sizing, layout, and specification
✔ Installation support and operator training
✔ Ongoing service, parts, and troubleshooting
Serving municipalities and facilities across Upstate NY and New England.
FAQ: De Nora Systems & Applications
What’s the difference between the TETRA LP® and U Block® underdrains?
- Both offer efficient air and water distribution. U Block® is used in higher-rate filters and provides increased surface area and structural integrity.
How do Denite® filters help with nutrient removal?
- Denite® filters biologically convert nitrate to nitrogen gas, reducing TN in the final effluent to meet stringent discharge permits.
Can SAF® or ColOX® be retrofitted into existing tanks?
- Yes. These fixed-film biofilters are modular and can be adapted to retrofit installations or new construction.
Is UV disinfection effective against viruses and protozoa?
- Yes. De Nora UV systems are validated to inactivate Cryptosporidium, Giardia, and viruses—meeting EPA and state disinfection standards.
What PFAS levels can De Nora’s ion exchange systems achieve?
- They can treat to non-detect or below 4 ppt depending on influent concentration and resin selection.
Are SORB™ media systems NSF certified?
- Yes. SORB™ media is NSF 61 certified and designed for safe use in drinking water systems.
Do these systems require backwashing or regeneration?
- Filtration systems require periodic backwashing; ion exchange and SORB™ media may require replacement or regeneration depending on the application.
Are pilot systems available?
- Yes. Both Siewert and F.R. Mahony can assist with pilot testing and field demonstrations to confirm performance.
What are the footprint requirements?
- TETRA™ filters and biofilters are highly space-efficient and customizable to available footprint and hydraulic profile.
Can these be used in decentralized systems or small municipalities?
- Absolutely. Many De Nora systems are modular and ideal for small- to mid-sized utilities or package plants.
Your Regional De Nora Partners in the Northeast
With strong regional representation, Siewert Equipment and F.R. Mahony ensure responsive, knowledgeable support for De Nora filtration and disinfection technologies. From small town water systems to large municipal treatment plants, we help you select, install, and maintain the right solutions for safe, clean water.
- New York (serving all Upstate NY) through Siewert Equipment, with offices in Rochester, and Albany.
- New England (serving all New England) through F.R. Mahony, with offices in Rockland, and Oxford.
Ready to Improve Your Treatment System?
Contact Siewert Equipment or F.R. Mahony to learn how De Nora technologies can meet your filtration, disinfection, and compliance goals.
De Nora: Trusted Water & Wastewater Treatment Innovations
Choose De Nora for proven treatment systems that deliver results—paired with local expertise from Siewert Equipment and F.R. Mahony.
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