Electrochemical chlorine generator preferred for dairy process water disinfection

Control chlorine residual and minimize chlorate

One on-site generator solved multiple problems

Our New Zealand distributor  – Visentia was approached by a dairy processor in New Zealand, to provide a disinfection solution for their process water (used for washing and as an ingredient in their infant formula product).

Two problems existed:

Chlorination of municipal potable supply to factory not reliable

Chlorine residual varied between 0.00 and 1.50 ppm. The customer required very good control of chlorine residual to ensure consistent disinfection performance.

Exisiting disinfection method created too much chlorate by-product

Extremely low chlorate is required in the water and product. Chlorate is a precursor for perchlorate and the presence of either compound is anathema. A previous supplier had sold them a 2-chemical chlorine dioxide generator to improve disinfection, but they had not considered the impact on chlorate formation. Chlorine dioxide reacts slowly with residual chlorine to form chlorite and chlorate. Chlorine dioxide reacts with organic and inorganic demand to form chlorite and chlorate. Some 2-chemical generators produce chlorate in the reactor and chlorate is present in the chlorite precursor. The result – too much chlorate.

Options they considered:

  • Electricide® CDE electrochemical chlorine dioxide generator. The customer already had this generator on site for a different application. Trials were conducted using the 2,000 ppm ClO2 solution to disinfect the water. Result: lower chlorate than the 2-chemical generator, but not low enough to be acceptable.
  • Liquified chlorine gas. They did not want to store chlorine in drums or cylinders on site.
  • 12.5% sodium hypochlorite (bleach). High concentration of chlorate in freshly produced bleach and quick degradation in storage to form more chlorate. This option would only increase chlorate in the water.
  • Calcium hypochlorite. Running cost is too high.
  • Electricide® HG-10-G On-site chlorine generator using Electricide-B1 brine feed. This option ticks all the boxes. Chlorine gas is generated on-site and dosed into the process water main, prior to a large water storage tank. No storage of Dangerous Goods and low running cost. Zero addition of chlorate to the water.

Result

The HG-10-G chlorine generator was installed and has been operating for 12 months. Chlorate concentration in treated water after the generator is extremely low. Chlorine residual is maintained at 0.45 ppm when the free chlorine concentration in the muncipal supply is less than this value. When the muncipal supply concentration is greater than 0.45 ppm, the HG generator is idle. Overall, an excellent outcome.

What is the Electricide® HG Chlorine Generator?

The Electricide® HG chlorine generator is an electrolytic system for converting sodium chloride (salt) into chlorine. Electricide-B1 is a purified brine precursor that is fed into the HG generator at the anode side of the electrolytic cell, where chloride ion is oxidised to chlorine. Chlorine gas is extracted under vacuum and dissolved into water using a booster pump and eductor. Chlorine gas reacts with the water to form HCl and HOCl.  The generator is configured to accept either salt (NaCl) in 20 kg bags or Electricide-B1 solution. The generator is skid mount and easy to install on site.

Chlorine Generation Reactions:

① Anode (oxidation): 2Cl → Cl2 + 2e

② Cathode (reduction): 2H2O + 2e → H2 + 2OH

Chlorine gas is extracted from the anodoe solution (anolyte). NaOH at the cathode (catholyte) is either wasted or re-used for pH correction.

What is good about it?

  • Safety. Only one precursor chemical is required – Salt (NaCl) brine solution and this is non-hazardous. Chlorine gas is produced directly at the generator, on demand and is not stored. It is creation of chlorine gas from a non-hazardous precursor.
  • Stability. There is nothing to degrade. Brine precursor is stable in storage and chlorine gas is generated fresh on demand.
  • Purity. The chlorine gas produced by the HG generator adds zero chlorate, sodium and chloride to the water. This can be important for food production where low chlorate and perchlorate in the food product are important.
  • Simplicity. The generator is simple to operate, install and maintain.
  • Remote access. Web server access using any browser is standard with email alarms.
  • Reliability. High quality components and controlled precursor purity equals excellent reliability.

Interested?

The Electricide® HG generators are available for purchase or rental, direct or through our distributors.

Generators are configured to use vacuum purified granular salt or Electricide-B1 solution.

In most cases, you can install and commission the generator with remote assistance (web or phone). Dioxide Pacific can install and commission the system if desired. Installation is a simple process for mechanical and electrical technicians.

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Contact us for more information or a quotation.

Cannabis powdery mildew and odor control

Greenhouse resolves potential problems with powdery mildew, odor and blocked drippers

The CDEB-2.5 chlorine dioxide generator produces both ClO2 solution and gas

Commercial production of medical cannabis (marijuana) is allowed in many countries and some US States. The plants are often grown in large greenhouses, requiring treatment systems for water and air.

Three risks are managed:

Air can contain powdery mildew spores which damages final product for the growing operation

Chlorine dioxide destroys powdery mildew spores. This produces a quantifiable $$ saving for the operation, to justify its use. Chlorine dioxide gas is extracted from the CDEB generator and dosed into ducts feeding air to various locations in the greenhouses. Through a proprietary method, the concentration of ClO2 is maintained within the optimal band between underdosing (no effect) and overdosing (phytotoxicity – damage to plants).

Result: Cannabis powdery mildew control.

Air exhausted from the greenhouse contains odors which require treatment

Greenhouses can be located near residential developments and odorous air may cause complaints. Chlorine dioxide oxidises organic isoprene odors at low concentration. Odor control is a side-benefit of powdery mildew control.

Result: Odor reduction to acceptable standards.

Irrigation water can grow biofilm and block drippers

Chlorine dioxide is excellent for biofilm control at low residual. Chlorine dioxide solution at 2,000 ppm (2 g/L) is produced in the generator and stored in a small batch tank. This solution is dosed by metering pumps into the water reticulation pipework. Control is by automatic flow pacing.

Result: Excellent biofilm control.

Other options they considered:

  • Manual preparation of ClO2. There are methods for preparation of ClO2 where two precursor chemicals are mixed in a tank by hand. This is dangerous as operators are exposed to ClO2 gas at the preparation tank. ClO2 gas is not directly available with this method

Interested?

The Electricide® CDE generators are available for purchase or rental, direct or through our distributors.

In most cases, you can install and commission the generator with remote assistance (web or phone). Dioxide Pacific can install and commission the system if desired. Installation is a simple process for mechanical and electrical technicians.

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Contact us for more information or a quotation.

NSF/ANSI 61 & 372 Certified Chlorine Dioxide Generators

Perfect for Potable Water and Health Care Use

NSF/ANSI 61 & 372 Mark Truesdail US and Canada

Who certified the generators?

Truesdail Laboratories Inc. (now part of ALS Global) has certified the generators.

View our certification here.

Which models are certified?

The following Electricide® electrochemical chlorine dioxide generators models to NSF/ANSI 61 & 372:

  • CDEB-2.5  Capacity: 47 g/hr = 2.5 lb/day
  • CDE-10  Capacity: 189 g/hr = 10 lb/day
  • CDE-25  Capacity: 472 g/hr = 25 lb/day
  • CDE-50  Capacity: 945 g/hr = 50 lb/day
  • CDE-100  Capacity: 1,890 g/hr = 100 lb/day
  • CDE-200  Capacity: 3,780 g/hr = 200 lb/day
  • CDE-300  Capacity: 5,670 g/hr = 300 lb/day
  • CDE-400  Capacity: 7,560 g/hr = 400 lb/day
  • CDE-500  Capacity: 9,450 g/hr = 500 lb/day
  • CDE-600  Capacity: 11,340 g/hr = 600 lb/day
  • CDE-700  Capacity: 13,230 g/hr = 700 lb/day
  • CDE-800  Capacity: 15,120 g/hr = 800 lb/day
  • CDE-900  Capacity: 17,010 g/hr = 900 lb/day
  • CDE-1000  Capacity: 18,900 g/hr = 1,000 lb/day

Which applications require certification?

Applications related to municipal potable water and health care water treatment (hot and cold water systems in hospitals and aged care facilities) require NSF/ANSI 61 & 372 certification for chemical generators. Dioxide Pacific has obtained this certification to ensure the above-mentioned generators can be installed and operated in these applications.

What is NSF/ANSI 61 & 372?

The aim of NSF/ANSI 61 is to ensure that the generator does not add any undesired health related compounds to the water via the chemical it generates. NSF/ANSI 372 ensures that no lead is added to the generated ClO2 solution.

Note: NSF/ANSI 61 addresses health effects only and does not address the disinfection efficacy of the product

Why is it important?

Many States in the US require NSF/ANSI 61 & 372 certification for chlorine dioxide generators. Even if it is not peremptory, this certification is reciprocal in other countries as recognition of high chemical generation purity and therefore lowest risk for potable water and water for use as an ingredient in food products or for washing.

How do the generators work?

The Electricide® electrochemical chlorine dioxide generators produce 2,000 ppm chlorine dioxide solution which can be dosed and controlled to 3 dosing points. The generator PLC/HMI  automatically measures ClO2 residual and controls dosing of ClO2 solution to ensure accurate disinfection. Generators are equipped with secure remote access capability to view, operate and receive email alarm notification.

Contact us for further information and pricing.

Electricide Chlorine Dioxide and Chlorine Generators CE Marked

Suitable for European Use

The Dioxide Pacific Electricide® CDE, CDEB, HG and HGB Chlorine Dioxide and Chlorine Generators are now CE Marked. This marking ensures their suitability for sale and operation in Europe.

We are looking forward to expanding our customer and distributor base throughout Europe for many and varied applications related to water disinfection and treatment.

Interested? Contact Us

CE Mark

Generate Hypochlorite from Salt – Safe and Clean in Food Environment

Safety concerns with using 12.5% sodium hypochlorite

Safety is always a concern to plant managers

Recently, we received an inquiry from a customer indirectly servicing the food industry. Their water is used for washing and must be clean and disinfected. They were looking for a disinfection method that would minimize their safety risk on site. Filtration+UV was chosen as the primary method although they realized it would not be sufficient on it’s own as the reticulation pipework would require a chemical residual of either chlorine (hypochlorite) to prevent biofilm growth.

Chlorine Considerations

This is how the customer perceived the various alternatives:

What is the Electricide® HGB Hypochlorite Generator?

The Electricide® HGB chlorine generator is an electrochemical system for converting sodium chloride (salt) into chlorine. Electricide-B1 is a purified brine precursor that is fed into the HGB generator at the anode side of the electrolytic cell where chloride ion is oxidised to chlorine. Chlorine combines with the hydroxide formed at the cathode to make sodium hypochlorite solution at 5-25 g/L (as NaOCl). The generator is skid mount and easy to install on site. Electricide-B1 chemical is available ex stock from Dioxide Pacific.

Chlorine Generation Reactions:

① Anode (oxidation): 2Cl → Cl2 + 2e

② Cathode (reduction): 2H2O + 2e → H2 + 2OH

① + ② (combined) 2Cl + 2H2O → Cl2 + H2 + 2OH

Chlorine reacts with caustic catholyte to form sodium hypochlorite and salt.

Cl2 + 2NaOH → NaCl + NaOCl

What is good about it?

  • Safety. Only one precursor chemical is required – Electricide-B1 and this is non-hazardous. The hypochlorite solution produced is 5-25 g/L at pH 9 – 9.5. This compares with commercial bleach at 12.5% (125 g/L) at pH 12. The lower concentration hypochlorite is much safer to handle and store.
  • Stability. The lower concentration hypochlorite produced by the HGB generator is 25 times more stable in storage than commercial bleach. Longer life means lower cost.
  • Purity. The hypochlorite solution produced by the HGB generator is extremely low in chlorate, sodium and chloride. This can be important for food production where low chlorate and perchlorate in the food product are important.
  • Simplicity. The generator is simple to operate, install and maintain.
  • Remote access. Web server access using any browser is standard with email alarms.
  • Reliability. The generator membrane cell is guaranteed when Electricide-B1 is used as the precursor.

Interested?

The Electricide® HGB generators are available for purchase or rental. Rental can include maintenance.

Electricide-B1 chemical is available in IBC’s (totes), 200L (55 gal) or 15L (5 gal) drums.

Dioxide Pacific can install and commission the system if desired. Installation is a simple process for mechanical and electrical technicians.

Download the Brochure pdf-icon-aa-30x30

Contact us for more information or a quotation.

Dairy Processor Replaces 2-Chem Chlorine Dioxide Generator

Electricide Electrochemical Chlorine Dioxide is Preferred Choice

Background – Chlorine Dioxide Disinfection

Dioxide Pacific recently provided an Electricide CDE-25 (472 g/hr – 25 pounds per day) electrochemical chlorine dioxide generator and dosing system to replace a traditional 2-chemical generator utilising 33% HCL and 25% sodium chlorite. This Australian dairy processor treats four water streams from the one generator including mains water and condensate.

Why Change?

The 2-chemical generator had ongoing reliability issues, plant room corrosion from HCL fumes and reduction in water alkalinity (pH). After an extensive evaluation process by an external consultant, the Dioxide Pacific Electricide electrochemical generator was chosen as the preferred replacement.

Advantages

The pertintent advantages of the Electricide generator are:

  • Use of only one precursor chemical
  • No acid – existing acid storage can be removed
  • Lower reduction in alkalinity (reduction in caustic use for pH correction)
  • Higher purity chlorine dioxide – no sodium, chlorite, chloride, chlorate added from the generator
  • Production of consistent 2,000 ppm ClO2 solution for dosing
  • Remote access via web server

System Description

In this system, chlorine dioxide solution at 2,000 ppm is produced in the generator solution tank and transferred via level control to a 1,500L FRP external storage tank. Four metering pumps dose from the outlet of this external tank to the four dosing points. Dosing is controlled from the generator HMI/PLC using different modes. There are three water storage tanks which are circulated. Each of the three tanks is controlled to a set ClO2 residual using PID control. One tank (mains water) also has flow paced dosing. Water entering the tank is dosed via flow pacing and the mains water in the tank is dosed to a PID setpoint. The combination of flow paced and PID provides accurate residual control.

Dioxide Pacific provided the complete system including generator, metering pumps, residual analyzers, chemical transfer system and storage tanks. Metering pumps with isolation valves, load valves, pressure relief valves and gauges were assembled on a skid. Analyzers and probe holders were mounted on a backboard. Electricide-P1 chemical is provided by Dioxide Pacific in IBC’s (totes). This chemical is formulated to provide chlorine dioxide conversion and long life for the electrolytic cell. The system was installed inside a purpose built shed by the customer.

Does this sound like something you could use?

Chlorine dioxide is ideal for disinfection of water used in food & beverage processing. You may be using chlorine or a 2-chemical chlorine dioxide generator for your water disinfection. If this information has piqued your interest, contact us for more information or a quotation.

Dioxide Pacific CDE-25 electrochemical chlorine dioxide generator.

Dioxide Pacific CDE-25 electrochemical chlorine dioxide generator. Generation of chlorine dioxide solution from single precursor chemical: Electricide-P1.

Electricide Electrochemical Chlorine Dioxide Generator for water disinfection

Electricide chlorine dioxide generator, dosing system and residual analyzers

Chlorine dioxide solution dosing skid

Chlorine dioxide solution dosing skid

Chlorine Dioxide for CIP Sanitization

Dioxide Pacific has supplied Electricide electrochemical chlorine dioxide systems for CIP sanitization in food and beverage applications with great results. In many cases, chlorine dioxide has replaced peracetic acid mixes. Typically, chlorine dioxide is applied at 1-3 ppm and can be dosed into the sanitisation rinse (flow paced) or made up as a 1-3 ppm solution (PID controlled) and pumped to through the system. Peracetic acid is typically used at 50-100 ppm.

One such food ingredient producer has been using the Electricide CDE10 generator for 3 years. They were using peracetic acid dosed from a tote (IBC) using a metering pump and paying $80k per year for chemicals. During connection of a tote, an operator came into contact with the chemical. Peracetic acid has a pungent vinegar smell which aggravates eyes and burns the skin (peroxide ingredient). Management decided to look around for an alternative and decided chlorine dioxide should be trialed. After 3 months of successful operation, the system was purchased and installed. Current yearly running costs are around $10k and the capital purchase was paid back in less than 1 year. The customer is happy with the improved safety aspects of chlorine dioxide as Electricide-P1 (the chlorine dioxide precursor) has no vapor and is easy to connect to the Electricide generator. Chlorine dioxide solution at 2,000 ppm is pumped to a CIP make-up tank where 3 ppm solution is made-up and controlled. The 2,000 ppm solution is safe to pump through UPVC pipe and the 3 ppm solution has no corrosion issues in stainless steel tanks and pipework. One benefit of the Electricide electrochemically generated chlorine dioxide is the purity of the solution produced – no chloride and close to neutral pH. Other methods of chlorine dioxide generation produce chlorine dioxide with low pH and high chloride which increase the risk of stainless steel corrosion.

Chlorine dioxide can be used as a final rinse as it will not react to form any odor or taint producing by-products in food and beverage products. This aspect will save a lot of water and energy. Usually, peracetic acid requires a lot of water as a post-rinse to remove the chemical. Chlorine dioxide does not require this post-rinse.

If you have a CIP sanitization application and would like to do the numbers on chlorine dioxide, contact Dioxide Pacific. Take a look at the features of the Electricide generator.