Water can dissolve just about anything—from sugar to cement. One thing it cannot dissolve, however, is oil… thus the old adage, “Water and oil don’t mix.” The electrons of the water molecule are similar to those of sugar or cement; therefore, the substance will become soluble at some point. On the other hand, the electrons in the molecules of hydrocarbons such as oil are not similar to water and, therefore, they repel one another.
For example, if oil is added to a bottle of water and shaken, one will notice the molecules of each substance separate from one another. Oil will float because hydrocarbons are lighter than water. In a pool or hot tub, oil can be introduced in a number of ways—suntan lotions, sunscreens, deodorants, makeup, and hair care products. Almost everything people apply to their skin contains oil. Further, natural body oils from bathers can also be drawn into the water as well.
Oil in pool water can cause numerous problems. It will combine with small particles of dirt and debris to form scum that will stick to the waterline and filter media, requiring additional work and maintenance. Oil in pools and spas/hot tubs have been an ongoing problem for more than 50 years. It becomes more prevalent, however, during the summer months with the increase in use of sunscreens and other sundry products.
In the last 30 years, two naturally based technologies have led the way in fighting and removing oils along with the problems they cause. One is chitosan and the other is enzymes. This article will look at these two technologies and discuss their similarities and differences, as well as how they can work together.
What are enzymes?
Biologically speaking, enzymes are catalysts or agents of change. Their purpose, on a cellular level, is to accelerate chemical reactions quickly. Enzymes are actually non-living proteins that speed up the break down process so that reactions, which would normally take much longer to accomplish, can be produced at a faster rate.
How do they work?
The main job of enzymes in living organisms is to reduce the level of toxins and enable the production of adenosine triphosphate (ATP), which is the prime ingredient for energy and muscle growth in living animals.
Enzymes work in the digestive system to break down foods into absorbable units that can be better assimilated into the body. They have also been used for many years in water treatment systems, including pool and spa/hot tub water. In recreational aquatics, enzymes act like chemical knives cutting up and reducing oils, greases, and proteins to their elemental building blocks of carbon dioxide and water. A good broad-spectrum enzyme formula will include many types of enzymes to deal with numerous non-living organics that can lead to common pool maintenance issues.
Types of enzymes
- Lipase—to break down fats and greases.
- Protease—to break down proteins.
- Cellulase—to break down cellulose.
- Amylase—to break down starches and carbohydrates.
Naturally based or manufactured enzymes?
The best type of enzyme for pool water are those made from a natural fermentation process that results in broad spectrum and naturally balanced-based enzymes, as they serve to rapidly break down non-living organic material. Non-living organic material can be things like soaps, sweat, lotions, and pollen. There are also manufactured formulas which tend to have higher concentrations of smaller amounts of unbalanced, enzymes that can be unstable and break down each other—even in the container. Manufactured enzyme products may be less effective on the broad range of non-living organics commonly found in pool water.
The wonder hidden within the shell of crustaceans
In the late ’70s, nearly six- to eight-million tons of waste, from the processing of crustacean shells, was being dumped into bays and landfills annually. This was primarily from seafood processors from Seattle to Alaska. The Environmental Protection Agency (EPA) stepped in and deemed the shell waste a pollutant and ordered seafood processors to find a more useful way to dispose of it. As a result, a team of research scientists were brought in to solve the problem and they discovered that within the shell of crustaceans (e.g. like crab, shrimp, and lobster) was something very similar to cellulose from plants. Chitin, a long-chain polymer derived from glucose, which is also found in the cell walls of fungi like mushrooms, gives the armor plating to the shell of crustaceans. Through a simple process, researchers found they could create a highly effective formulation of chitosan.
Chitosan is a naturally based, biodegradable biopolymer. It acts as a cationic (positively charged) polyelectrolyte. As a result, the molecule is an extremely long straight chain with high molecular weight and dense electrical charges.
It has been used throughout history for many things, including the varnish for Stradivarius violins, burn-wound bandages, contact lenses, and for clarifying beer and wine during the brewing process. More recently, chitosan has been used as a dietary supplement source of fiber and for weight loss. Chitosan is effective at grabbing fats and oils in the digestive system and removing them to waste before the body absorbs them.
Chitosan in water
Chitosan is a long-chain polymer with strong positive-charged hooks along the chain. It is because of this structure that chitosan is such an effective flocculant. Most micron-sized suspended particles in water have a negative charge. The chitosan molecule sweeps the smaller micron materials and causes them to become filterable and easily removed from the water.
Chitosan in pool water
Chitosan in a liquid or dry form can be used as a powerful water clarifier. There are also two things that make chitosan different from the synthetic clarifiers that are currently available. First, most synthetic formulas contain some petroleum (i.e. oil) which gathers dirt and non-living organics but can lead to clogged filters and unsightly scum lines. The unique structure of a chitosan clarifier has the ability to not only gather but also completely remove non-living organics and hydrocarbons.
Understanding the difference between a coagulant and a flocculant
Most synthetic clarifiers are strictly coagulants meaning they are effective at grabbing negative-charged micron particles and forming coagulated larger particles. These larger particles may or may not be removed by filtration. The micron limit of the filter being used determines if the coagulated particles are capable of being removed. One example would be a high-rate sand filter that is only capable of removing particles down to 25 microns. Therefore, any smaller coagulated materials could continue to pass through.
A strong polyelectrolyte such as chitosan has the ability to not only coagulate but also form bridges that gather several coagulated particles onto an aggregate known as a floc. The flocs formed by chitosan are termed ‘neutrally buoyant.’ This means the flocs of chitosan are so near the weight of water that they neither sink nor float, but are held in suspension to be removed by the filter. As chitosan is a non-petroleum clarifier, it is much more effective at removing the highest amount of non-living organic material using a complete flocculation method. The result is clearer water and cleaner filters.
A great synergy for clean water
Which is better… a broad spectrum enzyme or a chitosan-based clarifier? The answer is both. When enzymes are used in conjunction with chitosan, there is a synergistic clearing of the water. While enzymes are working to quickly break down non-living organics, chitosan is working to gather and flocculate materials as well. Also, chitosan is more tolerant to higher chlorine levels and can act as a backup to enzymes when a pool or spa/hot tub is being shocked.
Many pool professionals who have incorporated a maintenance system comprising chitosan and enzymes have reported improved water clarity. Incorporating both enzymatic digestion along with highly effective flocculation removal of non-living organic particles leads to excellent water clarity. The cost to integrate an enzyme and chitosan clarifier is very minimal compared to the savings in time and labor involved to frequently clean filters and waterlines. The removal of non-living organic particles also means a better swimming experience for bathers with better feeling water and the reduction of unpleasant odors.
Today, there are now many blended enzyme and chitosan clarifier products available on the market. These products provide a double-edged sword approach for pool and spa/hot tub professionals in making sure their customers have the clearest water possible. These unique technologies can accomplish so much together and are worth incorporating into a pool and/or spa/hot tub maintenance program.
This article was written by Terry Arko and originally appeared on Pool & Spa Marketing [link].