About Us

For more than 35 years, Severn Trent De Nora (STDN) has been a leading provider of water disinfection systems using onsite generated sodium hypochlorite produced from seawater or brine. In fact, our predecessor companies, Eltech Systems Corp., and Industrie De Nora, invented the electrode coatings that created a Dimensionally Stable Anode (DSA®), a non-sacrificial anode technology that permits the on-site generation of sodium hypochlorite.

Severn Trent De Nora is the combination of the onsite sodium hypochlorite generation businesses of Severn Trent Services and Industrie De Nora. The joint venture encompasses the products, services, and operations of their respective subsidiaries, Exceltec International Corp. and De Nora Seaclor, S.r.l. The product lines included are BALPURE®, CECHLO, ClorTec® , MARINER OMNIPURE® Series M55, OMNIPURE™, OMNIPURE™ Series 55/64, SANILEC® and SEACLOR® .

STDN's full range of electrolytic disinfection solutions address global water and wastewater treatment needs and are offered with standardized and accepted international industry standards, documentation packages and services, throughout the life of the installation. STDN also offers a broader range of services including upfront design and optimization assistance, supply of engineered systems, through to installation, erection, commissioning and maintenance.

Markets Served:

  • Coastal Industry
  • Desalination Facilities
  • Marine, General
  • Navies Worldwide
  • Offshore Oil & Gas Facilities
  • Power Generation

Product Lines and their applications:

BALPURE® is a proprietary and Type Approved electrolytic disinfection ballast water treatment system. Using a slip stream approach, the BALPURE system can be remotely mounted away from the main ballast lines. The system is most commonly supplied in six small, sub-assembly components. It can be installed in the most convenient location to suit vessel machinery, minimizing the relocation of other equipment or the need for engineering or ship re-designs. It features low power requirements – less than half of some competing systems; low maintenance requirements; and simple operation. Accommodating ballast water treatment for vessels ranging from 500 to 20,000+ m3/h, the BALPURE system is especially advantageous for crude oil tankers, chemical/product tankers, LNG/LPG carriers, bulk carriers and container ships.

CECHLO electrochlorination systems for the on-site generation of sodium hypochlorite, is a well-established product line in Japan and was developed over 35 years ago. CECHLO-M produces the required amount of sodium hypochlorite through the electrolysis of the seawater. When seawater is not available, brine based electrochlorination systems CECHLO-MS/NS/IS are ideal applications that produce sodium hypochlorite from brine. CECHLO-MS/IS systems employ Ion Exchange Membrane technology to produce sodium hypochlorite at high concentration.

ClorTec® on-site sodium hypochlorite generation systems have a strong reputation as the leading global technology provider with a proven track record of 3,000+ global installations. ClorTec on-site sodium hypochlorite generation systems have been designed, manufactured, installed, operated and serviced since 1995. The ClorTec systems generate a 0.8% sodium hypochlorite disinfection solution, a chlorine equivalent, using three common consumables: salt, water and electricity. ClorTec units range in capacity from up to 1 kg/day or 2 lb/day to 1,360+ kg/day or 3000+ lb/day, while ClorTec systems are engineered and offered to meet any specified application demand. To meet varying application specific conditions, the ClorTec units are available as component-based or skid-based packaged systems.

MARINER OMNIPURE® Series M55 Marine Sanitation Devices offer a fresh approach to sewage treatment in the vessel, workboat and yacht markets while resulting in wastewater effluent quality well below the MEPC.159(55) requirements. The MARINER OMNIPURE Series M55 units incorporate the same electrolytic treatment benefits of any other OMNIPURE unit, but with the added advantages of less maintenance and a small, compact size to fit vessels in the target markets. Systems can accommodate treatment capacities up to 75 persons (black water) and up to 25 persons (black and gray); the largest unit treats a peak flow of 2,160 gallons (8,176 Liters) of human wastewater per day. The MARINER OMNIPURE Series M55 systems have received Bureau Veritas certification for IMO Resolution MEPC.159(55).

OMNIPURE™ systems are the only marine sewage systems that oxidize sewage in the electrochemical cell as well as generate NaOCL for the disinfection of the marine waste streams. OMNIPURE is certified by the United States Coast guard (USCG) and is in compliance with the International Maritime Organization (IMO). Chinese and Russian Authorities have also certified that OMNIPURE meets their stringent environmental standards governing the discharge of wastewater in territorial waters.

OMNIPURE™ Series 55/64 systems are the only marine sewage treatment system that oxidizes sewage in an electrochemical cell as well as generates sodium hypochlorite for the disinfection of the sewage streams. Systems offer effective electrolytic treatment of both black and gray water through a certified process and range in treatment capacities up to 65 m3/day (17,000 gallons/day). Individual units that can be combined for increased capacity. The proprietary OMNIPURE Series 55/64 systems have received Bureau Veritas certification for IMO Resolution MEPC.227(64) and USCG Certificate of Approval to MEPC.227(64).

SANILEC® systems take full advantage of our knowledge and experience in the design of offshore skid mounted units, with strenuous area classification requirements. These systems generate sodium hypochlorite from seawater using an extensively field-proven electrochemical process for the disinfection of both water and wastewater. SANILEC systems range in capacity from 2.8 to 47,620 lb/day (1.2 to 21,600 kg/day), per train.

SEACLOR® systems are the standard for power plants and desalination facilities, as well as coastal installations using seawater for cooling or other process needs all over the world. The extensive installation list as well as the reliable performance makes SEACLOR the preferred electro-chlorinator in the industry. SEACLOR systems range in capacity from 500 to 50,000 lb/day (10 to 900kg/hr), per train.


Severn Trent Services
Severn Trent Services, with global headquarters in Horsham, Pa., USA, is a leading supplier of water and wastewater solutions. The company’s Water Purification business, based in Colmar, Pa., USA, provides innovative disinfection, instrumentation and filtration technologies for the municipal, energy and marine markets. Our water treatment technologies are backed by a global support network of experienced customer service representatives, application engineers and field service technicians. Severn Trent Services is a member of the Severn Trent Plc (London: SVT.L) group of companies. Severn Trent is a FTSE 100 company.

Visit www.severntrentservices.com for more information.

Industrie De Nora
Founded in 1923 as an electrochemical engineering company, Industrie De Nora has become a world leader in engineering, procurement and construction of complete plants for the electrochemical industries. The Group presently operates through ten companies strategically distributed throughout Europe, Asia and America and is the largest world-wide supplier of Dimensionally Stable Anodes DSA® for the chlor-alkali industries. Industrie De Nora has an annual turnover of $600 million and employs a staff of around 1,500 people.