Chlorine Generators For Swimming Pools

Chlorine generators are very useful because they eliminate the need to physically store chlorine chemical products. The generator produces chlorine by utilizing a mixture of sodium chloride salt and water. This type of salt water chlorine generation system is one of the first form of alternative pool sanitizer, to be introduced to the swimming pool and spa industry.

Chlorine generation on site, will eliminate the need for you to buy, transport, handle, and store any type of swimming pool chlorine product which can be costly.

How Do Chlorine Generators Actually Work?

There are currently two known methods used in swimming pool chlorine generation. Both of these methods use electrolysis as their main source of chlorine production. Chlorine production in this process, is achieved from the salt (sodium chloride salt) that is added to the pool water.

Through electrolysis, electricity is introduced to the salt water solution in the cell of the generator.

As a result, chlorine gas is produced.

As your pool water passes through the cell of the generator, the electricity is introduced.

The salt in the water is converted into Hypochlorous acid as it passes through the generator cell.

The hypochlorous acid that is produced, is the exact same as that which is produced from other types of chlorine products available, when they are added to water. It does not matter if you use any of the pool chlorines listed below...

Swimming Pool Chlorine Sanitizers

  • Swimming pool chlorine tablets.
  • Swimming pool chlorine sticks.
  • HTH pool chlorine (otherwise known as granular chlorine).
  • Liquid chlorine.

Either way, hypochlorous acid will be created when you add any of these chlorine products to water. When your pool water leaves the cell of the chlorine generator, it will introduce the newly mixed chlorinated water to your swimming pool or spa.

The job of this on-site generated chlorine is the same as the other swimming pool chlorine products that are used in the industry today. What does this means? It means that this generated chlorine will...

  • Help control algae growth.
  • Help control bacteria.
  • Kill off swimming pool pathogens.

Chlorine sanitizers will also create a safe and sanitary swimming environment for you, your family, and friends.

What Actually Happens Inside Pool Chlorine Generators?

Inside the cell of a pool chlorine generator, the saline water solution is sanitized through electrolysis as mentioned earlier. The electrolytic cell breaks down the water into its basic elements. These basic elements are hydrogen and oxygen. This process is achieved by introducing a small electrical charge to the swimming pool or spa water.

Adding granulated salt (similar to regular household salt) as the electrical charge is being introduced, will produce hypochlorous acid. At this point, you are probably asking often will I need to add salt to this type of swimming pool system? Well! Ultimately, this form of pool chlorine generation converts the hypochlorous acid back into salt.

So with a swimming pool chlorine generator system, the salt only has to be topped off occasionally. This is usually once or twice a year.   You may also have to add salt if your pool/spa is used constantly. Reasons for this is due to water splash out and/or backwashing of your swimming pool filters. Still, just having to add salt once or twice a year is a big cost savings for you.

Types Of swimming Pool Chlorine Generators

Presently there are two types of chlorine generation that are used in swimming pool care. The first of these chlorine generation methods is called the In-Line generation method and the second is called the Brine Method. We will now look at each of these methods more closely!

In-Line chlorine generation. In this method, chlorine is produced by utilizing salt that has been dissolved in a pool or spa water system. A low concentration of salt (usually between 3,000 to 3,500 ppm) is added directly to the pool or spa water. Chlorine generation is achieved by electrolysis which like I said before, occurs in an electrolytic cell or in multiple cells. 

These cells are plumbed directly in line in the existing piping or plumbing of your swimming pool water circulation system. Thus the name "In-Line chlorine generation". The internal structure of an in-line chlorine generator, contains two rare-metal plates. These plates are charged by a separate controlled DC voltage supply.

As I mentioned earlier, as your swimming pool water passes through the unit and electrical power is applied, the production of chlorine takes place. During this process, chlorine and sodium hydroxide are dissolved into the water. In addition, The hydrogen gas that is produced during the chlorine production process, escapes directly into the atmosphere.

With this type of pool chlorine generation, the water passing through the water generator cells becomes super-chlorinated. The results of this super-chlorination cause oxidizing of organic material and in-organic combined chlorine as well. Controllers that are normally installed on the swimming pool chlorine generators, routinely reverses the polarity of the electrodes in the generators.

The polarity of the switching is done to prevent any build up scales on the plates of the pool salt water generator. As the generated chlorine performs its duties as a pool disinfectant, it reverts back into salt. Hence, the same salt is used over and over again.

Salt replacement will only be necessary if there is too much water loss or pool dilution. Many in-line swimming pool chlorine generators have a digital control readout. These digital controls will indicate exactly how much salt you need to add for replacement purposes. Therefore adding too much or too little salt is avoidable.

Brine chlorine generation. The brine method of generating chlorine is in fact - a miniature chlorine plant. Brine chlorine generators are actually small boxes that consist of two chambers. The chambers of this chlorine water treatment system are separated by a small membrane.

This membrane allows the passage of sodium ions and electricity but it prevents chloride ions from passing through. So how do brine chlorine generators actually work? Well! The positive electrode (anode), the dissolved salt, and distilled water mixture are located in one chamber. The second chamber house the negative electrode (cathode) and water.

Electricity is applied to the chambers by a control device that converts AC voltage to a DC voltage of 4 to 6 volts. As the electrical current passes through the membrane of the generator, pool sanitizing chlorine is produced. The chlorine is produced as result of the reactions in the two chambers. Chlorine gas is then accumulated at the top inside the brine solution. The accumulation of chlorine gas is on the anodes (positive electrode side) of salt water chlorine generators.

The sodium ions are transported through the membrane and then into the cathode (negative side) chamber.

It is here that reaction takes place with the water. By this reaction, sodium hydroxide and hydrogen gas are produced. In brine chlorine generators - as long as the salt level is correct, your chlorine generation will be be correct also. How does the generated chlorine get into your pool water system you ask?

The chlorine gas that is now located in the anode chamber, will be drawn directly into your pool water circulation system. This is accomplish using a Venturi injector system. This is a device that is also used in an ozone vacuum system as well. At this point, the disinfection process of your swimming pool is the same as if you were using a gas chlorine-feed system.

There are reports that confirm that chlorine generating systems will provide you - with years of safely treated water, giving you a more refreshed feeling after a swim. Reports also have confirm, that the maintenance for salt water chlorine generators is very low.

Therefore, whether your choice is for the In-Line method of generating chlorine or the Brine method, there will be very low maintenance and low cost for your salt water chlorine generators.

Chlorine generators eliminate the need to store chlorine pool chemicals!

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