Ozone Properties

 INTRODUCTION

Although the properties of ozone have been known and studied since the mid-19th century, it is only during the last two decades that it has been applied in commercial and industrial contexts. Initially, circa 1906, ozone was used as a clarifying, deodorizing and purifying agent in drinking and waste water treatment plants in Europe, where it gained a level of acceptance over the years. In the late 1970's, its properties were investigated in the US by the Jet Propulsion Laboratory, NASA and various military installations. These studies confirmed the disinfecting and resource conservation benefits of ozone. Despite the broadened interest in ozone during the past two decades, it is only in recent years that interest has shifted to the utility of this substance for the commercial and industrial laundry industries. After several false starts, technology has advanced to the point that ozone can be applied usefully and profitably in this context. Research performed in the development of NuTek International Inc.'s Ozone Laundry Support System' (OLSS) has been instrumental in demonstrating the real benefits that can be achieved. The following sections summarize the results of NuTek's research and development program carried out over a three year period. ©1999 NuTek International, Inc.

PROPERTIES OF OZONE

Ozone is a gas with a pungent odor that is formed by the breakdown of elemental, diatomic Oxygen (02) and the recombination of a percentage of the oxygen atoms into a triatomic molecule (03). Although norrnal oxygen, a component of the atmosphere, is a powerful oxidizing agent in its own right, ozone has much stronger oxidizing properties and reacts more quickly, often in fractions of a second, with a wide range of substances. In addition, it is one of the most effective biocides known to science, better even than chlorine, bromine and other commonly used disinfectants. Unlike the latter substances, however, it does not form hazardous disinfectant by-products (DBP's) such as dioxin and nitrites that are harmful to the environment or are toxic to animals and hurnans. Once ozone has fully reacted with substances in water or air, excess gas decomposes quickly to normal oxygen and is reabsorbed into the atmosphere.

Ozone can be generated from two sources: ambient air or pure oxygen. Because it reacts so easily with other elements and is inherently unstable, it exists for only a short time before combining with another substance or reverting to normal oxygen. Accordingly, it must be generated on-site at the point that it is to be used. Unlike chlorine and other dangerous disinfectants, it does not need to be handled, transported or stored, thereby posing little hazard to personnel at the facility. Finally, when used in proper concentrations, ozone is an effective corrosion inhibitor, and in the wash room context can reduce the need for substances like chlorine, which are extremely corrosive for equipment and fabrics.

BENEFITS IN LAUNDRY

In its role as a powerful oxidant and biocide, ozone works in the context of commercial and industrial laundry wash rooms to boost the cleaning activity of the various chemicals and chemical compounds. It accomplishes this in several ways:

Replenishes oxygen in the wash water

Many chemicals in the wash cycle are themselves oxidants and require oxygen in their reactions with the different types of soils. Ozone, itself a form of oxygen, increases the supply of that substance, thereby increasing those chemicals' effectiveness as cleaning agents.

This allows a reduction of harsh chemicals in the wash cycle. A reduction which lessens cost and increases worker safely.

Purifies the wash water

Ozone oxidizes the soil components of the wash water causing them to form precipitates or to go into suspension so that they can more easily be removed from the wash.

By this process, the chemicals themselves are re-energized and the load on them is reduced, so they can be used in even smaller quantities and still be more effective.

Works at lower water temperature

Because ozone increases the saponification and lubricating effects of the wash chemicals, the wash does not need to be as hot. Instead of washing at the "traditional" temperatures of 140'F to 160'F, NuTek has demonstrated over and over again that comparable or better results can be obtained when the temperature is reduced by as much as 65%.

Cold water means less costly water. Cold water means less wear on the linen.

Disinfects the wash water

As one of the strongest commercially available microbiocides, ozone destroys all bacteria, viruses, blood pathogens and other harmful microorganisms found in the soiled fabrics.

Garinents are not only cleaner, but also do not pose the threat of passing along communicable diseases to either the users or the laundry workers.

Softens the wash water

Intake or source water often contains calcium, magnesium and other dissolved mineral salts that cause hardness. Ozone breaks these compounds into their individual radicals and causes them to form precipitates that can be removed by filtration. The wash is "soft' without the need for additional chemical softening agents.

Soft water means more suds from less detergent and better rinsing.

Decomposes fats, oil and grease (FOG)

Industrial laundries use strong chemicals at high pH levels to remove FOG from uniforms, mats and wipers. By infusing ozone into the wash water, these items are more easily and thoroughly cleaned with smaller quantities of harsh chemicals. The bonds that hold many of the FOG molecules together are broken and the carbon compounds are removed in the break water as dissolved C02.

Broken bonds of the FOG's means that even less detergent is neededfor the same cleaning results.

Replaces Chlorine Bleach

Ozone is a very strong oxidizer and can perform the same role as a bleach as does chlorine, but without creating harmful DBP's such as THM and dioxin. It also works with hydrogen peroxide in the bleach cycle to provide maximum bleaching power without producing dangerous side effects.

What this means is that using the OLSS™ reduces the possibility of side effects from chemicals that can harm employees and the environment.

Prevents Redeposition

Heavily soiled wash water often leads to the redeposition of the soil onto the fabrics being cleaned, causing a noticeable graying and color degradation of the material. By removing the soil elements from the solution and increasing the cleaning power of the chemicals, ozone prevents redeposition and causes a higher proportion of the soil to be removed in the break.

This means that the OLSS™ produces whiter fabries with less bleach.

Efficient Deodorizer

Odor in soiled fabrics is often caused by sulfur and nitrogen compounds or by petrochemicals in the soil. Ozone's ability to break the single and double bonds that hold the molecules together in those compounds allows it to eradicate the odors and, in cases where the latter result from microbes, to prevent them from recurring.

It should be noted that ozone has been used successfully by the dry cleaning industry to remove the smell of smoke, fish and other strong, odors from soiled garments.

Improves fabric "look and feel"

Items washed in ozone treated water come out smelling fresh and clean; even wipers have no oily odor and feel soft.

The overall effects of adding ozone to the wash cycle water are to produce fabrics that are as clean or cleaner than those from systems using conventional formulas, but with dramatically reduced quantities of water, energy, chemicals and formula times. NuTek has documented cases where installation of its OLSS™ has resulted in dramatic savings in all of these areas.