Electrolysis Disinfection

The nt-CLE system is the result of two decades of our research, development and continuous optimization. We have already produced the nt-CLE series ranging from 0.5 to 120kg/h (NaClO active ingredient) per electrolysis unit, which generates doses of up to 0.8% NaClO solution on site. All nt-CLE systems are planned, built, installed and delivered ready-to-use and with the necessary training and customized to the needs of the customer by taking the technical and climatic conditions and the quality of raw materials (water and salt) into account.

In addition to the large nt-CLE systems, newtec also has developed the compact series nt-BlueBox for salt water electrolysis with the following capacities: 3g/h, 5g/h, 30g/h, 60g/h, 90g/h, 200g/h and 300g/h.

Application of salt water and seawater electrolysis

The Salt water electrolysis with nt-CLE systems is mainly used in large waterworks, cooling towers, industrial process water plants, sewage treatment plants and agriculture. The nt-BlueBox is used in smaller cooling towers, wet separators, in greenhouses and in water installations of buildings treating legionella.

The seawater electrolysis with nt-CLE-S systems is mainly manufactured for large cooling towers in power or chemical plants on the shore for seawater desalination for LNG stations and seawater swimming pools.

Process

The nt-CLE series uses membraneless electrolysis tube cells and produces a sodium hypochlorite (NaClO) solution with a concentration of up to 0.8% for the active ingredient. According to Regluation (EU) No 1272/2008 (CLP) NaClO solutions with concentrations below 1% are not hazardous and are biodegradable.

For the production of 1kg NaClO approx. 3.5kg NaCl and 4kW are needed. During the electrolysis, a theoretical maximum of 0.35 liters of hydrogen is produced. The practical hydrogen emissions are far below this value. The ventilation system, which uses a large supply of fresh air to dilute the hydrogen, is designed to maximize hydrogen production (up to a safe concentration) for maximum safety.

There are basically two variants:

  1. Salt water electrolysis using salt and drinking water
  2. Seawater electrolysis utilizing the natural salinity of seawater

Salt water electrolysis

A plant for salt water electrolysis nt-CLE consists of a water softener, a brine tank, an electrolysis unit with rectifier, a product tank, metering and controls.

Capacity of the nt-CLE for salt water electrolysis: 0.5 to 40kg/h per electrolysis unit.
Concentration of the on-site produced NaClO solution: 0.5% to 0.8% active NaClO
Consumption (per kg NaClO): up to 3.5kg NaCl, 4kWh

Seawater electrolysis

The seawater electrolysis plants nt-CLE-S consist of submersible pumps, self-cleaning filters, an electrolysis unit with rectifier, a product tank, dosing pumps and controls as required.

Capacity of the nt-CLE-S series for seawater: 0.5 to 120kg / h per electrolysis unit
Concentration of the on-site produced NaClO solution: up to 0.25% active NaClO
Consumption (per kg NaClO): up to 4.0 kWh, no salt

Advantages of on-site electrolysis

Since 2000, newtec has continuously optimized the membraneless tubular cell electrolysis in order to achieve a maximum of customer satisfaction and adapt to the changing regulations in different countries through its own research, development and experience from the completion of more than 200 projects - including many large-scale projects worldwide.

Main advantages

  • Inexpensive on-site production of the active chlorine compound, minimal by-products such as chlorates through optimized electrolysis parameters; high effectiveness through immediate use
  • Legally compliant with the new EU biocides directive (No 528/2012), further product certification of the nt-CLE series in progress
  • The modern and flexible design ensures the best adaptation to the general conditions and customer requirements, e.g. electrodes with a particularly large distance
  • Best quality according to German standards, with a 5-year warranty for electrodes
  • Saving up to 20% of the electrolysis energy through integrated heat exchangers
  • Sensor-monitored and PLC-controlled automatic process with visualization of the overall process and logging of all important parameters and alarm signals
  • User-friendly operation and monitoring of the entire process is also possible for mobile devices such as tablet PCs or mobile phones
  • Consultation in the planning and support after commissioning, reliable complete service from a single sourced

Security

The electrolysis system nt-CLE is our solution to replace the dangerous liquid chlorine disinfection. Transport, storage, handling and dosage of barrels with liquid chlorine gas are subject to the highest hazard class. Serious accidents during transport, storage, handling and dosage kept occurring.

Before with liquid chlorine

Hazards during transport, storage, handling and dosage

Afterwards with our electrolysis

Free from the handling of hazardous substances

Maximum safety with newtec electrolysis on site

  • Without transport, storage or handling of hazardous chemicals such as chlorine gas / liquid chlorine or highly concentrated sodium hypochlorite (NaClO> 10%)
  • Our NaClO solutions up to 1% are according to Regulation (EU) No 1272/2008 (CLP) not hazardous and are biodegradable
  • Automatic monitoring of individual system components with different warning options and levels
  • Immediate hydrogen dilution to below 1%, with H2-Sensor monitoring, automatic monitoring with switching to a stand-by fan system
  • Operator training, in addition to safety measures, normally with testing and certificate from newtec

Example projects salt water electrolysis

Southern waterworks St. Petersburg, Russia

In 2006, the world's first large-scale on-site production facility for 0.8% of a safe sodium hypochlorite solution was built as a turnkey solution by newtec for the St. Petersburg waterworks in Russia.

newtec was responsible for the planning and construction of the plant as well as the delivery of the system, installation, commissioning and training. Since then, the plant has been working around the clock with a total capacity of 8 electrolysis units per 40 kg / h for the disinfection of 1.3 million m3 drinking water a day.

The application of the newtec technology and thus the elimination of hazardous liquid chlorine in one of the largest waterworks for the first time proves the feasibility and superiority of our technology, even for large waterworks.

Salt water electrolysis in the southern waterworks in St. Petersburg
Rectifier with utilization of waste heat in the southern plant

Northern waterworks St. Petersburg, Russia

In 2008, another plant with 5 electrolysis units per 40kg /h NaClO for the disinfection of 850,000 m³ of drinking water per day was handed over to customers by newtec.

With our nt-CLE plants, the drinking water of the entire city of St. Petersburg is disinfected with a daily volume of 2.15 million m³. Liquid chlorine depots have since been decommissioned. The taste and smell of the drinking water has been improved.

Salt water electrolysis in the northern waterworks in St. Petersburg

PJSC «Kazanorgsintez» Kazan, Tatarstan/Russia

In September 2017, newtec handed over a salt water electrolysis plant with 3 nt-CLE 40000 for drinking water disinfection to the customer. It was designed and built by newtec according to the new Russian electrolysis standard (Regulation No 554 of 20th November 2013).

At PJSC in Kazan / Russia, with 3 pcs nt-CLE 40000

Waterworks in Helsingborg, Sweden

Since 2013, a nt-BlueBox 90 has been used for the mobile drinking water disinfection of 20-100m³ / h and for the degradation of biofilms in pipelines of the distribution network for drinking water.

Waterworks in Helsingborg, Sweden

Example projects seawater electrolysis

Zhejiang Taizhou 2. powerplant, China

Seawater electrolysis 2x 50kg / h for cooling water disinfection in the 2x 1000MW power plant Taizhou, in operation since 2015.

Vizag thermal power station, India

Seawater electrolysis 3x 120kg / h for cooling water disinfection in the 2x 520MW power plant, in operation since 2012.