What is the Electrochlorination Process?

What is the Electrochlorination Process?

The electrochlorination process

What is the Electrochlorination process?

Electrochlorination is the process of applying an electrical current to salt water to produce dilute sodium hypochlorite (bleach) and hydrogen gas. The resultant sodium hypochlorite solution contains between 0.7%-1% chlorine. This low concentration is considered non-hazardous to humans yet still destroys viruses, bacteria, and other harmful microorganisms present in the water, making it safe to drink and preventing the spread of diseases. 

Unlike other chlorination methods, such as chlorine gas or commercial hypochlorite solutions, electrochlorination doesn’t generate any toxic by-products, nor does it require staff to handle hazardous chemicals, such as chlorine or sodium hypochlorite in high concentrations. The only by-product is hydrogen gas and there are processes to manage and disperse this safely.

Electrochlorination is therefore a highly effective and economical technique for disinfecting water. Unsurprisingly, it’s used all over the world, at all scales, from personal electrochlorination units carried by campers in remote locations to giant industrial plants treating potable water for an entire city. 

Electrochlorination produces sodium hypochlorite on site on an “as needed” basis. If required, electrochlorination can function as part of a responsive system that automatically generates a dosage of sodium hypochlorite depending on the existing levels of free chlorine or organic matter in the water. Here at ProDose, we install electrochlorination apparatus ranging in dosing capacity from 25 grams per hour right up to 10 kilograms per hour.

 

What’s involved in the Electrochlorination Process?

In very basic terms, electrochlorination is the electrolysis of salt water. This can be natural seawater or artificial brine produced by adding sodium chloride, or pure vacuum dried salt, to fresh water. In all brine based systems the incoming water (used to dilute the brine and dissolve the salt) is softened.This reduces calcium and magnesium salts dissolved within the water and prevents the build up of harmful scale deposits around the electrical components and within pipes. This improves the reliability of the system.

After cleaning, the filtered brine flows through a series of electrodes within an electrolytic cell. A low voltage DC current is passed through the solution. At the positive anode, chloride ions are oxidized to produce chlorine. At the negative cathode, the salt water is reduced to sodium hydroxide and hydrogen. The liberated chlorine reacts instantly with the sodium hydroxide to produce sodium hypochlorite, while the hydrogen gas is released. 

The chemical reaction is:

NaCl + H2O + ENERGY NaOCl + H2

The sodium hypochlorite solution flows onwards to a separate chamber or tank, where it is separated from the by-product, hydrogen gas.The sodium hypochlorite is typically low strength, with a moderate pH value. From here, it can be stored in the short term or immediately injected into the main water system where it goes to work, either as a continuous supply or a shock dose.

Would you like to find out more about our premium quality range of Electrochlorination systems?

Safe Dispersal of Hydrogen

The by-product hydrogen is highly flammable and has no smell. Therefore it should not be permitted to build up in significant quantities around the electrochlorination equipment as it could explode. Some kind of degassing system needs to be built into the process to make sure the hydrogen disperses safely. Prodose advocates the use of dual containment and force air ventilation of all hydrogen containing components within a plant room. This ultra safe method ensures that in the event of a leak of hydrogen (cracked pipe or leaking fitting) the hydrogen is immediately diluted with air to a concentration significantly below the 4% explosive threshold.

Choosing an Electrochlorination System

The ProDose team of experts has specified and installed more than 100 electrochlorination systems in the UK and worldwide. Our experience covers a variety of industries and applications, from food production to school swimming pools to drinking water treatment. We offer a range of AMPRO electrochlorinators to suit every operation, footprint, and budget, and we always include a full after-sale support package.

  • MPS Model – A simple wall mounted, lower capacity electrochlorination system, with self-cleaning electrode technology.
  • MP Models– Available in three capacities these electrochlorinators feature auto brine dilution, hydrogen degassing and force air ventilation, all in one compact wall mounted assembly. With an intelligent colour touchscreen control panel, operators can access running parameters, help screens and system diagnostics with ease.
  • MPI Models – Available in five larger capacities these floor mounted electrochlorinators are supplied fully assembled and ready for integration at site. These also feature auto brine dilution, hydrogen degassing, force air ventilation and intelligent touchscreen control panel as per the MP range.

Call us today to discuss your electrochlorination needs, whether you’re considering upgrading your existing system or installing an entirely new one.

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What is the Electrochlorination Process?

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Chlorine Dioxide and Legionella Control

Chlorine Dioxide and Legionella Control

Chlorine Dioxide and Legionella control

Chlorine Dioxide and Legionella Control

Legionella is a bacterium found in soil and water. When it occurs outdoors, it usually does so in low concentrations and doesn’t cause problems. However, when it grows inside artificial water systems, such as hot tubs, hot water tanks, swimming pools, decorative fountains, or cooling towers, it can multiply to dangerous levels and result in Legionnaires disease in humans. This is a serious form of pneumonia which can be fatal.

There are, in an average year, around 200-250 confirmed cases of Legionnaires disease in England and Wales. Approximately half these cases are the result of local contamination, while the rest can be traced to overseas travel. As it’s a major public health concern, the relevant local authorities must be notified of any Legionnaire’s disease diagnosis so the original source of infection can be investigated and eradicated.

As it’s such a serious health and safety issue, building owners and managers must stay on top of monitoring water supplies for the bacteria and administer treatments as necessary. In the UK, there are very specific health and safety regulations detailed in HSG274. Chlorine dioxide is one of the chemical treatments recommended for making water safe and protecting customers, staff, and residents from Legionnaires’ disease.

 

Why is Legionella so Dangerous?

Legionnaires disease is spread when people breathe the bacteria in via microscopic water droplets (aerosols), which then infects their lungs and/or respiratory system. It’s not passed from person to person, instead people moving through the same location are likely to become infected at the same time. 

Legionella outbreaks can occur in industrial, commercial, hospital, or even domestic settings, in fact anywhere where quantities of water are stored within the temperature range 30-42ºC. It becomes dormant at lower temperatures, but can revive as soon as the water warms up again. With the right nutrients, the Legionella population can double every 3-4 hours. It thrives in water systems where the usual flow (which disturbs colonies’ growth) is halted for a period of time, such as an office building that has been closed during a pandemic.

Cases of Legionnaires disease can be particularly dangerous in patients who are over 50, smokers, or have an underlying immunodeficiency disorder. Initial symptoms include cough and headache, but this can rapidly progress to chest pains, vomiting, and mental confusion. If left untreated, it may result in respiratory failure, septic shock, or acute kidney failure.

Looking for an efficient way to control the risk of Legionella in your premises?

How does Chlorine Dioxide Destroy Legionella?

Legionella bacteria develops inside a protective polysaccharide slime, or biofilm. This layer of microorganisms forms on surfaces that come into contact with water. At even a low concentration of 0.1 ppm, chlorine dioxide penetrates both the biofilm and the bacteria cell walls. It oxidizes the amino acids in the cytoplasm within cells, effectively destroying the bacteria and the nutrients they feed off. Chlorine Dioxide works rapidly and is effective over a wide temperature and pH range.

How is Chlorine Dioxide added to the Water System?

Chlorine dioxide is a volatile gas, which is difficult and potentially dangerous to store. Therefore it’s usually generated on site, as needed, in a stable solution form that is much safer to handle. Chlorine dioxide solution can be derived in a number of different ways, one of the most common is the controlled reaction of low strengths solutions of sodium chlorite NaClO2 and hydrochloric acid. The resultant chemical reaction forms chlorine dioxide (ClO2) and salt and water. As this solution is fresh, precise doses can then be injected into the water system as and where required, so the biocidal action can begin.

The team at ProDose has many years of experience with Legionella prevention and eradication. We can advise you on your level of compliance with the current Approved Code of Practice L8 for control of Legionella bacteria in water systems. We also have a great deal of expertise in designing and maintaining safe water treatment strategies for a variety of buildings, including offices, universities, hospitals, factories, schools, and sports stadiums. We can help you upgrade your existing system or provide you with the latest state-of-the-art equipment. The first step is to give us a call and set up a consultation.

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What is the Electrochlorination Process?

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If you are interested in upgrading your existing system or are looking for state-of-the-art equipment, please get in touch with us at Prodose. We’d be very happy to talk to you confidentially and on a no-pressure basis.

Chlorine Dioxide and Water Treatment for Plant Nurseries

Chlorine Dioxide and Water Treatment for Plant Nurseries

Chlorine Dioxide and water treatment for plant nurseries

Chlorine Dioxide and Water Treatment for Plant Nurseries

Horticultural facilities, such as plant nurseries, face many of the same water sanitation issues as their agricultural counterparts. These issues include keeping ornamental and food plants healthy, maintaining sanitized equipment, especially irrigation and water recycling systems, and controlling the growth of algae and other harmful microbes.

Treating water with chlorine dioxide solves these problems. It’s also safe, effective at a wide pH range (4-10), and cost efficient for most installations. Finally, chlorine dioxide is odor free, which means it in no way interferes with customers’ experience as they visit a nursery to pick out their plants.

Chlorine dioxide is easy to use. It is a water soluble gas that can be generated on site, as required, then injected directly into irrigation lines. It is an effective disinfectant at a low concentration, below 1.0ppm.

 

Chlorine Dioxide and Maintaining Plant Health

Most plant nursery owners would agree that keeping plant stock healthy (and therefore attractive to customers) is a big priority. Chlorine dioxide water treatment can be a powerful tool in the fight against plant disease. Even in relatively low amounts, chlorine dioxide added to water can protect against plant pathogens .

For instance, research has shown that chlorine dioxide prevents the spread of Fusarium oxysporum in daffodils during hot water treatment. When used as a dipping agent, it is also effective in reducing Botrytis grey mould in roses. If added to irrigation water, such as that gathered from collection ponds, it kills other pathogens such as Thieloviopsis basicola, Botrytis cinerea, and Clavibacter michiganesis. Chlorine dioxide is effective both if added in small amounts to the regular supply, or as a “shock treatment” at a higher concentration (20-50ppm) in order to target a specific outbreak of a pathogen, or as a periodic cleanse.

Chlorine dioxide is especially useful as a disinfestant as it can be used to control plant diseases during production and post-harvest.

 

Chlorine Dioxide and Eliminating Biofilm and Algae

The layer of green slime sometimes visible inside a water treatment system is known as biofilm, and it consists of a living mass of organic and inorganic elements that cluster together for survival. Unfortunately, biofilm and the organisms lurking within it thrive on any surface that is in regular contact with water, and that includes the irrigation and return lines, holding and mixing tanks, and containment vessels of typical plant nursery irrigation equipment. Biofilm also grows quickly inside liquid fertilizer lines. If its development is left unchecked, it can block pipes, affecting water flow and pressure, as well as spreading pathogens among plants.

Once again, chlorine dioxide water treatment solves the problem. Once dissolved in water, chlorine dioxide moves freely within the irrigation system. It attacks the surface of the biofilm, destroying it right down to the surface it sits on and, if part of a constant injection system, stops it from re-establishing itself. Chlorine dioxide prevents biofilm regrowth at concentrations as low as 0.25ppm in irrigation water.

Looking for an easier way to generate Chlorine Dioxide on site? 

Chlorine Dioxide and Irrigation, Runoff, and Water Recycling

Chlorine dioxide can be added to a plant nursery irrigation system with minimal environmental consequences— as long as levels are constantly monitored. When it reacts with microbes, chlorine dioxide does not form any harmful compounds such as trihalomethane, chloramines, chloroform or other halogenated disinfection by-products (DBPs). It dissipates swiftly once water is exposed to air. This means that treated run-off water can continue to circulate within the irrigation system, reducing labour and waste costs. As chlorine dioxide functions as a disinfectant in such a dilute form, it’s not necessary to clean the system after its use with aggressive chemicals, which may corrode plastic pipes and limit equipment life.

If you’re interested in learning more about chlorine dioxide as a water sanitization solution for plant nurseries and other horticultural businesses, please contact the team at ProDose. We have many years of experience in this specific field and can design, install and maintain every element of your irrigation system, as well as supplying all necessary chemicals. Give us a call today!

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Keeping it clean: the use of Chlorine Dioxide in the Food and Beverage Sector

Keeping it clean: the use of Chlorine Dioxide in the Food and Beverage Sector

keeping-it-clean

Keeping It Clean: the use of Chlorine Dioxide in the Food and Beverage Sector

Chlorine dioxide is rising in prominence as the best water treatment additive for the food and drinks industry. It’s powerful and economical, and may be a more practical solution for food-grade facilities than other options such as chlorine or bromine. Chlorine dioxide is also relatively odorless, another big plus for this sector.

What is Chlorine Dioxide (ClO2)?

Chlorine Dioxide is a fast acting disinfectant, used in many different water treatment systems around the world. It’s a yellow or reddish-yellow gas, which breaks down into chlorine gas and oxygen when heated. Chlorine dioxide is quite volatile so it is usually manufactured as a stable solution on site and on demand to avoid some of the issues associated with safe storage.

How is Chlorine Dioxide solution made?

Chlorine dioxide solution can be derived in a number of different ways, one of the most common is the addition of sodium chlorite NaClO2 and hydrochloric acid. The resultant chemical reaction forms chlorine dioxide (ClO2) and salt and water.

Alternatively, a stabilized chlorine dioxide solution can be activated by small doses of a strong acid at timed intervals. This will release low quantities of gaseous chlorine dioxide.

How does Chlorine Dioxide work?

Once added to water, Chlorine Dioxide goes to work very quickly. It remains stable in solution (unlike Chlorine) and therefore remains effective over a wide pH range. It doesn’t react with background organic matter in water (again unlike Chlorine) so it reaches the bioorganisms it’s designed to kill in larger quantities, more immediately.

Chlorine dioxide works as a bactericide, fungicide and antimicrobial agent, eliminating pathogens from the water and from the surface of washed produce. First, chlorine dioxide penetrates the biofilm, the protective polysaccharide “glue” that holds clusters of microbes together. As it doesn’t react with the inert sugars in this layer, it remains at full strength for the next stage. It then works by attacking the microbe’s amino acids and RNA, breaking down cell walls and preventing any further growth.

How does Chlorine Dioxide affect water?

Chlorine dioxide sanitizes water without generating the same environmentally damaging byproducts as its competitors. For instance, chlorine bleach and bromide produce carcinogenic trihalomethanes when added to water. By contrast, Chlorine Dioxide breaks down to water, oxygen and common table salt, making clean-up much easier.

Chlorine dioxide is effective as a disinfectant across a wide range of water pH values. This means it’s suited to the closed loop systems commonly used by the food and drinks industry. When it reacts with bioorganisms, there is no resultant taint or odour – again crucial when washing meat, poultry, fish, or produce.

Looking for an easier way to generate Chlorine Dioxide on site? 

How does Chlorine Dioxide affect equipment?

Chlorine dioxide is an effective sanitizer at concentrations as low as 5 parts-per-million (ppm). As well as making it environmentally friendly, this means it’s much less corrosive to the stainless steel equipment vital to any food processing or washing plant . By contrast, systems that use hypochlorite solution often operate at much higher residual levels, and at these levels there can often be a detriment corrosive reaction with steels. This leads to extra repair and replacement costs, not to mention down time. Chlorine dioxide is also a very fast acting disinfectant, which makes it ideal for short contact cleaning, further reducing the wear and tear on a water treatment system.

Can an existing water treatment system be converted to Chlorine Dioxide use?

If you have questions about the use of Chlorine Dioxide as a disinfectant in your specific water treatment system, please contact us here at ProDose. Our team of experts have many years of experience with chlorination processes and have installed sanitization systems in many different food and drink production facilities. We’re more than happy to discuss your options, from designing and installing a new system, to adapting and maintaining your existing set up. We also supply chemicals. Call or email us to schedule an appointment to discuss your water treatment needs.

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read more

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Chlorine Dioxide: the practical choice for water treatment in the UK

Chlorine Dioxide: the practical choice for water treatment in the UK

Chlorine Dioxide the practical choice for water treatment in the UK

Chlorine Dioxide: the practical choice for water treatment in the UK

What is Chlorine Dioxide?

Chlorine dioxide (ClO2) is a yellow or reddish-yellow gas. It’s a highly reactive compound, especially when heated. When exposed to the air, sunlight breaks it down into chlorine gas and oxygen. Chlorine gas is toxic if inhaled. Chlorine dioxide turns to liquid below 11ºC   and can be frozen into an orange-colored solid, for instance for shipping, although it must be carefully monitored during transit.

As chlorine dioxide is such a volatile compound, difficult to store or transport safely, it is usually manufactured in solution form at the point of use, as and when required. It does not occur naturally. Chlorine dioxide, when dissolved in water, is an efficient disinfectant and is used around the world to make drinking water safe. Chlorine dioxide solution has many other industrial and agricultural applications, including bleaching paper and fabric, and disinfecting food processing equipment.

How is Chlorine Dioxide made?

Chlorine dioxide can be explosive and cause burns in gas form, so it is most commonly manufactured as a stable solution. Chlorine dioxide solution is generated through the acidification of sodium chlorite. This process involves adding sodium chloride crystals or flakes to water (producing sodium chlorite NaClO2) and a food-grade acid (e.g., phosphoric acid, hydrochloric acid, citric acid, malic acid, or sodium hydrogen sulfate). This combination generates chlorous acid (HClO2), which decomposes to a specific and controlled mix of chlorite (ClO2), chlorine dioxide (ClO2) and chloride (Cl ̄).

Alternatively, a stabilized chlorine dioxide solution is “activated by adding small doses of a strong acid. This releases low quantities of gaseous chlorine dioxide over a period of time.

Why is Chlorine Dioxide such an effective water treatment?

Although chlorine is usually the chemical associated with water treatment, chlorine dioxide is a better choice for many reasons. Both chlorine and chlorine dioxide are highly reactive, but chlorine dioxide has the advantage in that it only reacts with a narrow range of chemicals. It remains stable across a wider range of pH values than chlorine: it’s only active in the pH4-10 range. It does not react with the vast majority of organic compounds therefore it is easier to control and has more of an effect at lower residual levels than either chlorine or another competitor, ozone.

One of the main reasons for sanitizing the water supply is to destroy biofilms, the slimy collection of molds, viruses, and bacteria that may be found growing on the surface of equipment. Biofilms often build up in pipework, or in the warm environments offered by hot and cold water systems in buildings and cooling towers.

The microorganisms in biofilms include disease-causing pathogens such as E.coli, Salmonella, Campylobacter and Listeria so it’s important to prevent their development and stop the spread of any spores. The microorganisms cluster together and secrete a protective polysaccharide “glue” that helps them to resist outside elements.

Chlorine dioxide penetrates this slimy outer layer by breaking down the inert sugars. Unlike other biocides, chlorine dioxide then continues reacting with the proteins that the microorganisms are built from, disrupting cell function and preventing them from reproducing. Chlorine dioxide is particularly effective at preventing the build-up of Legionella, Giardia Lambia and Cryptosporidium oocysts in public drinking water supplies.

Another reason to choose chlorine dioxide over chlorine is that it does not form disinfection by-products (DBPs) such as chloramines and halogenated compounds (Trihalomethane or THMS). Chloramines can taint the water, causing an unpleasant taste and/or odour. Obviously, it’s crucial that the water used in agricultural and food processes is odourless and tasteless so it doesn’t contaminate the product. Chlorine dioxide disinfects without side-effects.

Finally, chlorine dioxide oxidises swiftly as it only reacts with a narrow range of chemicals. This means it goes to work on the problem more quickly than other disinfectants and at lower residual levels. Chlorine dioxide is a much more precise, fast-acting water treatment solution than chlorine and its other competitors. 

Looking for Chlorine Dioxide Generators? 

What is Chlorine Dioxide?

Chlorine dioxide (ClO2) is a yellow or reddish-yellow gas. It’s a highly reactive compound, especially when heated. When exposed to the air, sunlight breaks it down into chlorine gas and oxygen. Chlorine gas is toxic if inhaled. Chlorine dioxide turns to liquid below 11ºC   and can be frozen into an orange-colored solid, for instance for shipping, although it must be carefully monitored during transit.

As chlorine dioxide is such a volatile compound, difficult to store or transport safely, it is usually manufactured in solution form at the point of use, as and when required. It does not occur naturally. Chlorine dioxide, when dissolved in water, is an efficient disinfectant and is used around the world to make drinking water safe. Chlorine dioxide solution has many other industrial and agricultural applications, including bleaching paper and fabric, and disinfecting food processing equipment.

How is Chlorine Dioxide made?

Chlorine dioxide can be explosive and cause burns in gas form, so it is most commonly manufactured as a stable solution. Chlorine dioxide solution is generated through the acidification of sodium chlorite. This process involves adding sodium chloride crystals or flakes to water (producing sodium chlorite NaClO2) and a food-grade acid (e.g., phosphoric acid, hydrochloric acid, citric acid, malic acid, or sodium hydrogen sulfate). This combination generates chlorous acid (HClO2), which decomposes to a specific and controlled mix of chlorite (ClO2), chlorine dioxide (ClO2) and chloride (Cl ̄).

Alternatively, a stabilized chlorine dioxide solution is “activated by adding small doses of a strong acid. This releases low quantities of gaseous chlorine dioxide over a period of time.

Why is Chlorine Dioxide such an effective water treatment?

Although chlorine is usually the chemical associated with water treatment, chlorine dioxide is a better choice for many reasons. Both chlorine and chlorine dioxide are highly reactive, but chlorine dioxide has the advantage in that it only reacts with a narrow range of chemicals. It remains stable across a wider range of pH values than chlorine: it’s only active in the pH4-10 range. It does not react with the vast majority of organic compounds therefore it is easier to control and has more of an effect at lower residual levels than either chlorine or another competitor, ozone.

One of the main reasons for sanitizing the water supply is to destroy biofilms, the slimy collection of molds, viruses, and bacteria that may be found growing on the surface of equipment. Biofilms often build up in pipework, or in the warm environments offered by hot and cold water systems in buildings and cooling towers.

The microorganisms in biofilms include disease-causing pathogens such as E.coli, Salmonella, Campylobacter and Listeria so it’s important to prevent their development and stop the spread of any spores. The microorganisms cluster together and secrete a protective polysaccharide “glue” that helps them to resist outside elements.

Chlorine dioxide penetrates this slimy outer layer by breaking down the inert sugars. Unlike other biocides, chlorine dioxide then continues reacting with the proteins that the microorganisms are built from, disrupting cell function and preventing them from reproducing. Chlorine dioxide is particularly effective at preventing the build-up of Legionella, Giardia Lambia and Cryptosporidium oocysts in public drinking water supplies.

Another reason to choose chlorine dioxide over chlorine is that it does not form disinfection by-products (DBPs) such as chloramines and halogenated compounds (Trihalomethane or THMS). Chloramines can taint the water, causing an unpleasant taste and/or odour. Obviously, it’s crucial that the water used in agricultural and food processes is odourless and tasteless so it doesn’t contaminate the product. Chlorine dioxide disinfects without side-effects.

Finally, chlorine dioxide oxidises swiftly as it only reacts with a narrow range of chemicals. This means it goes to work on the problem more quickly than other disinfectants and at lower residual levels. Chlorine dioxide is a much more precise, fast-acting water treatment solution than chlorine and its other competitors.

What are the types of chlorination used in water treatment?

There are three main methods of chlorinating water, depending on the strength of the disinfectant required. Chlorine compounds can be added to the water as:

  • Liquid (in the form of sodium hypochlorite);
  • Solid, in the form of powder, granules, or tablets, made from calcium hypochlorite, chlorinated isocyanurates or lithium hypochlorite;
  • Gas (highly toxic and only used under special conditions).

When chlorine or a chlorine compound is added into water it releases hypochlorous acid, HOCl. The hypochlorous acid commonly disassociates into other forms, such as the chlorite ion, OCl-, depending on the pH of the water. The amount of chlorine in the water in these forms is referred to as Free Chlorine. The reaction of chlorine with organics to form compounds such as chloramines is referred to as combined chlorine.

How is Chlorine Dioxide applied in water treatment?

Chlorine dioxide water treatment is a versatile process that can be adapted to many different types and sizes of facilities. Depending on the strength and speed of biocidal action required, chlorine dioxide can be generated on site and on demand from tablets, solutions, or via electrochlorination. This allows the operator to control the concentration of chlorine dioxide within their water system. The most common type of generators form chlorine dioxide as an aqueous solution of consistent product strength from the controlled reaction of Hydrochloric Acid and Sodium Chlorite.

As mentioned above, chlorine dioxide can also be stored and used in the form of Stabilised Chlorine Dioxide. This is an aqueous buffered solution of chlorine dioxide, activated through the addition of an additional acid solution. Some facilities find this to be a more convenient method of chlorination. 

What are the benefits of Chlorine Dioxide water treatment to industry?

As a swift and efficient biocide, chlorine dioxide has many applications. It destroys bacteria, viruses, fungi and other pathogens on hard surfaces and within water supply systems. It can be added to any hot or cold water system, including cooling towers, swimming pools, and spas to destroy problem bacteria and viruses such as Pseudomonas, MRSA, E-coli, and cryptosporidium. 

Chlorine dioxide is a vital component of the sanitization process at every stage of agricultural production, storage, and distribution. It’s also valued as a disinfectant for large buildings, such as office blocks, hotels, laboratories, and hospitals – especially those which might be vulnerable to legionella growth within their water supply. It’s employed across the hospitality sector as an all-round sanitizer and antimicrobial agent.

If you have questions about the use of Chlorine Dioxide in water treatment, please contact us. The Prodose team has more than ten years of expertise in this area and we can advise on all aspects of your water disinfection system. We offer end-to-end water treatment service, designing and installing your system, supplying chemicals, and servicing. Prodose is your one-stop shop for Chlorine Dioxide water treatment.

 

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What is the Electrochlorination Process?

What is the Electrochlorination process? Electrochlorination is the process of applying an electrical current to salt water to produce dilute sodium hypochlorite (bleach) and hydrogen gas. The resultant sodium hypochlorite solution contains between 0.7%-1% chlorine....

read more

Chlorine Dioxide and Legionella Control

Chlorine Dioxide and Legionella Control Legionella is a bacterium found in soil and water. When it occurs outdoors, it usually does so in low concentrations and doesn’t cause problems. However, when it grows inside artificial water systems, such as hot tubs, hot water...

read more

Chlorine Dioxide and Water Treatment for Plant Nurseries

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read more

If you are interested in upgrading your system in this way, please get in touch with us at Prodose. We’d be very happy to talk to you confidentially and on a no-pressure basis.

Is Sodium Hypochlorite The Best Way To Treat Water For The Food Industry?

Is Sodium Hypochlorite The Best Way To Treat Water For The Food Industry?

Is Sodium Hypochlorite The Best Way To Treat Water For The Food Industry?

Is Sodium Hypochlorite The Best Way To Treat Water For The Food Industry?

Sodium hypochlorite (NaOCl) is a greenish-yellow liquid produced by combining chlorine and sodium hydroxide. Commercial sodium hypochlorite is manufactured by adding chlorine gas to caustic soda, which produces sodium hypochlorite, water and salt. Alternatively, when smaller amounts are required, sodium hypochlorite can be produced on site by dissolving salt in softened water. This results in a concentrated brine which can be electrolyzed to form a sodium hypochlorite solution.  

How is Sodium Hypochlorite currently used in the food industry?

Sodium hypochlorite has many applications in agriculture, food and beverage industries. Sodium Hypochlorite maintains water quality through oxidation or disinfection. It destroys harmful microorganisms and prevents algae or shellfish from growing in stored water. It’s an essential component in many sanitisation processes, including washing fruits and vegetables, and the preparation of meat and fish for consumption. As it’s the main ingredient in household bleach, it’s used on factories and farms for cleaning and disinfecting equipment. It’s widely used to disinfect potable water and wastewater in certain countries.  It’s an effective treatment for private water supplies from boreholes, also called wells, and where water is stored prior to use in industry.

How does Sodium Hypochlorite work as a disinfectant?

Sodium hypochlorite functions as a disinfectant in a similar manner to chlorine and is very effective against viruses, bacteria and fungi as it strips away microbial cell walls and renders nucleic acids non-functional, preventing these organisms from reproducing. When added to water, it forms hypochlorous acid (HOCl) and a chlorite ion (OCl-) otherwise known as free chlorine. 

The ratio between HOCl and OCl- depends on the pH and the temperature of the water. At 25°C and pH 7.5, the chlorine is divided equally between HOCl and OCl-. It may be necessary to acidify the water as part of the process in order to get the desired proportions – ideally with more hypochlorous acid in the mix as this is the best disinfectant. As the hypochlorite ion is negatively charged, it bounces away from microbial cell walls, which are also negatively charged. The chlorite ion is also bigger than the HOCl molecule so it diffuses more slowly. Hypochlorous acid is usually the best option as it’s a stronger oxidising agent than the hypochlorite ion.

Hypochlorous acid degrades rapidly when it comes into contact with organic matter so it does not have a lasting environmental impact. As with other forms of chlorine, regular testing of the pH and chlorine levels in treated water is necessary to ensure that local quality standards are being met. 

What precautions should be taken when storing commercially available Sodium Hypochlorite? 

The sodium hypochlorite solution normally available from chemical suppliers is safer and more convenient to store than chlorine gas, but it breaks down if exposed to sunlight, high temperatures, or vibrations. When it’s stored for a long period of time the solution degrades, so good stock management is essential. The higher the original concentration of the solution, the more rapidly it breaks down. It should be stored in a cool room in an opaque (ideally black) container. Sodium hypochlorite is caustic and can irritate, even burn, the eyes and skin on contact, so it needs to be handled by trained staff using protective gear.

The need for controlled storage is one of the main drawbacks of using Sodium Hypochlorite, along with the health and safety protocols involved. It can be difficult and expensive to store large amounts over time. In order to maintain standards, an agricultural production company might need to keep large quantities of other chemicals like chlorine dioxide and peracetic acid on site for washer disinfection. This means placing regular orders with a chemical supplier, costing upwards of £100K per annum.

Is there an alternative to bulk storing Sodium Hypochlorite?

At Prodose, we have developed a unique electrochlorination system that uses common salt, water and electricity to dispense a low pH Sodium Hypochlorite into your water supply as and when required. No hazardous chemicals are needed for this reaction, so storage isn’t a problem. It’s a much safer process than chlorination using commercial sodium hypochlorite as the solution remains below the 5% concentration threshold considered hazardous by the UK Health and Safety Executive. 

Our electrochlorination systems are geared to the size of your operation and range in dosing levels from 100 grams per hour up to 10 kilograms per hour. This simplifies the production process with increased automation, saves on running costs (chemicals cost around £10K per annum), and improves efficiency. We’ve installed these electrochlorination systems in a wide range of facilities, including cleaning in place (CIP) for a leading soft drinks company.

To learn more about the latest water treatment techniques, including alternatives to Sodium Hypochlorite, please contact the team of expert chemical engineers at Prodose. We specialise in developing unique solutions to your water treatment problems, and electrochlorination may well be the technology you’re looking for.

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If you are interested in upgrading your system in this way, please get in touch with us at Prodose. We’d be very happy to talk to you confidentially and on a no-pressure basis.