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Energy efficiency is not usually associated with laundering the many different types of linen that pass through health care facilities. Hygienically clean linens are a necessity, and the traditional means of getting them clean involves many chemicals, hot water, and high sewage costs. However, ozone laundering, a relatively new method used in all major upcoming countries, is changing the perception of laundry as a non energy-efficient necessary evil.
The concept of washing clothes with the aid of ozone (O3) gas dissolved in ambient temperature water was first introduced to the American laundry industry in 1991. The system touted the capability of reducing energy use and traditional wash chemicals while recycling most of the wash water for reuse. Since that time, the number of laundries embracing this technology has grown dramatically. Ozone occurs in nature as a result of electrical discharge (for example, lightning), ultraviolet radiation, or the photochemical action of sunlight on atmospheric oxygen. European scientists learned how to recreate these reactions in controlled laboratory experiments in the latter part of the 19th century and by the turn of the century the first ozone generators were being produced commercially in France and Germany.
Ozone is a colorless gas that in low concentrations has a slight odor, most often described as the smell of fresh air after a thunderstorm. Extremely unstable, ozone cannot be stored and must be generated on site. It is one and a half times as dense as oxygen and about 13 times more soluble in water. Table 1 shows ozone to be second only to fluorine in its oxidizing potential and 150% more powerful in its disinfecting capabilities than chlorine.
In an aqueous solution, it is an effective biocide, capable of destroying bacterial and viral colonies. It is also effective against molds and fungi and as a deodorizer of air and water. Ozone works well as a disinfectant because upon disintegration it reverts to its original form, oxygen (O2). It dissipates quickly in water temperatures more than 38ºC (104ºF), which mandates the use of lukewarm water. Ozone has been utilized for more than 100 years in Europe in positive applications as diverse as primary disinfection of municipal drinking water supplies, aquaculture, and pulp bleaching. Its widespread use in the United States has been hampered by the preference for inexpensive chemicals (especially chlorine) compared with the expensive, generally unreliable ozone-generating equipment. But with mounting federal government pressure to reduce chemical pollution of the environment, coupled with the development of cost-efficient, reliable, and low-maintenance ozone-generating systems, these systems are gaining popularity. The main benefits of Laundering with ozone are as follows:
Cost Saving Advantages
Hot Water (Energy) Savings (70% - 90%)
Conventional washing methods require that 70% of wash water be heated to temperatures in ranges of 60º to 82ºC (140º to 180ºF) for proper stain removal when used in conjunction with conventional chemicals. With the ozone washing system, no water is heated to more than 32ºC to 35ºC (90ºF to 95ºF), and then only in heavily soiled wash loads.
In warmer climates such as Florida's, where groundwater temperatures are already elevated, no additional heat is required. While there is more electrical consumption and cost associated with this system, the cost increase is small when compared with the savings resulting from the reduction or elimination of hot water.
Note : In certain states (New Hampshire, Washington, California [where the regulation is under review for repeal], and Pennsylvania [where it is unenforced], acute care facilities* are required to use 71ºC (160ºF) wash-water temperatures and keep the linen immersed in these temperatures for a minimum of 24 minutes. This regulation was originally enacted nationally in 1938 as a result of studies by L.A. Arnold, which demonstrated that exposure to water temperatures of 71ºC for 24 minutes would kill nearly all bacterial forms other than spores. Laundering at lower temperatures was less effective because the tallow-based soaps and other detergents in use at that time required hot water for proper emulsification. It was not until energy costs began to rise in the early 1970s that this issue was revisited. Extensive testing performed by the Veterans Administration proved that modern detergents coupled with water dilution in the wash wheel, chlorine bleach, the mechanical action of the washer, and the heat contact of dryers or ironers produced "hygienically clean" linen (virtually free of pathogenic microorganisms). There are no documented cases of nosocomial infection being spread via processed hospital laundry. At this time, with the exception of the few states noted above, there are no regulations regarding the use of water temperature in health care facilities.
Chemical Cost Reduction (60% - 65%)
Ozone enhances the power of detergents by breaking water surface tension and nullifying the water-hardening effects of Calcium and Magnesium. Ozone makes water soft without the use of traditional water softening equipment. Your laundry detergent will go a lot farther. When you first switch to a Water Energy Ozone Standard, unless you have brand new linens, you will have suds whether or not you add any soap for the next 4 or 5 times you wash them. There is so much residual soap and chemicals that you will be amazed at how many suds you get without adding any soap! This should clearly illustrate just how much soap remains in your linens with traditional laundering methods. Switch to ozone and greatly reduce the amount of chemicals needed to provide superior results. Stop all those chemicals from getting on your guests or patients. The linens smell and feel like new instead of having that 'odd' smell and scratchy feel characteristic of towels in a hotel or hospital.
Typical laundry produces wastewater that is high in BOD (biological oxygen demand - food for bacteria) high in COD (chemical oxygen demand) and low in DO (dissolved oxygen). This is to be expected with the nature of the soil and chemical contaminants found on dirty linen. The soil consists of body oils and other secretions, food and other organic waste, organic stains like blood and grass stains, etc. Chemicals found in a laundry's wastewater include the strong alkali described above, hefty amount of chlorine bleach, lots of detergent, acid, fragrances, softeners, and more. All of this adds up to mean the wastewater coming from a typical laundry is not very nice. The high BOD, COD and low DO are all counter-productive to what they are trying to accomplish down at the local wastewater treatment plant. They are trying to lower the BOD and COD and raise the DO so when they discharge the water, it won't damage the receiving stream's water habitat. Or put more simply, it won't kill the fish! The negative factors of a laundry's wastewater (BOD and COD) support the growth of algae in rivers which consumes all of the dissolved oxygen (DO) and thereby suffocates the fish. Who would have known! So, laundries must go to expensive measures to 'buffer' their wastewater and reduce its negative aspects before releasing it to the sewer. If they don't, in some cases the laundry owner can be charged additional fees by the sewer provider or fined for unacceptable wastewater discharge. Some companies pay a lot of money in fines or impact fees because of their poor quality wastewater.
With a Water Energy ozone standard in your laundry, the ozone replaces most of the chemicals needed to provide a superior finished product. Ozone, being made purely of oxygen, first oxidizes and destroys odors, stains, bacteria, viruses, parasites, cysts, oils and greases and reduces them to carbon dioxide, inert material and water. Think about it, all organic substances are made of long-chain carbon molecules. Stains, odors, living organisms, oils etc. are all made of these molecules. Water with high concentrations of dissolved ozone is full of Hydroxyl Radicals and on contact, they clip the molecules and instantly attach to the Carbon to form something else, the most of which is CO2 or Carbon Dioxide gas. This Carbon Dioxide gas floats harmlessly into the air - the same gas that comes out of a newly-opened soda or out of your mouth when you breathe. What is left is certainly not a stain or odor or living organism.
These Hydroxyl Radicals are OH molecules that have an insatiable desire to bond with something else. Each time they do, they are delivering oxygen to the material that creates the BOD (biological oxygen demand) and neutralizing the oxygen demand. What a win-win situation. The OH is happy and now the wastewater people are happy. Also, any remaining ozone, oxygen or OH molecules after all the work is done simply raise the DO (dissolved oxygen) content in the water. Wow, that's a win-win-win situation there and the fact that this is all superlatively green in nature (adding oxygen to the environment instead of who knows what chemicals) you've got a win-win-win-win situation!!! There aren't too many of those in this Old World these days. Now that you've eliminated the BOD & COD and raised the DO, your laundry wastewater will actually benefit the process down at the local wastewater treatment plant.
Eliminating Chlorine and other harmful chemicals and reducing the amount of detergent used to process your linens will greatly improve the air quality in and around your laundry facility. Eliminating the use of Chlorine means the elimination of huge amounts of VOC's coming from your laundry! No more acid and greatly reduced alkali means your linens will last much longer and not shed as much lint in the dryers. This will greatly reduce the amount of airborne particles coming from your dryer vents which will greatly reduce the volume of particulates in the air. Particulates are a major source of pollution that pervades our environment today. You won't be able to see the improvement to your air quality but knowing you aren't discharging the typical load of environmentally hazardous chemicals to the air will give you peace of mind and much cleaner air.
Greatly Extend The Life Of Valuable Linens
Reap huge savings by extending the life of your valuable linens from 2 to 7 times. A Water Energy Ozone Laundry Standard will greatly extend the life of your valuable linens by eliminating the harsh chemical treatments found in traditional wash chemistry. Ozone very effectively oxidizes soil, oils & greases, bacteria, viruses and other contaminants in your linens without the need to subject them to the typical hellish mixture of chemicals in the washer. A pH of 11+ is enough to cause permanent injury to your eyes, skin, hair, etc. so you can imagine what it is doing to your fabric. Huge swings in pH cause untold wear and tear on your expensive linens. Very high pH causes fibers to swell unnaturally which leads to cracks in the fibers themselves. These cracked fibers shatter and are carried away by your dryer. Your expensive linens are being reduced to fuzz every time you wash them.
With ozone, your pH stays near neutral and that's exactly what your body is and your linens are - neutral. By eliminating all of the harsh chemicals in the wash, you eliminate the harsh residue in the finished product. In laundry, you never actually get everything out in the rinse. A rinse simply serves to dilute the contaminants. When you add a lot of alkali and then acid to neutralize it, that doesn't mean it just disappears, actually it creates a mineral salt that remains in the fabric. The rinse cycle only reduces the concentration of this residue, it does not eliminate it. These residual salts are made up of crystals deposited in the fabric and their sharp edges accelerate the destruction of your valuable fabrics during the drying process. This mineral salt also remains in the towels and sheets after drying and ends up on your body when you use them. Most of us don't stay in bed long enough for the mineral salts to cause any real damage to our skin but bed-ridden patients in Nursing Homes and Hospitals are subject to skin eruptions, boils and other skin ailments that lead to bed sores and have a negative impact on their overall health. When you adopt a Water Energy Ozone Laundry Standard, you truly eliminate the chemical residues in the finished product because you've eliminated the chemicals altogether.
Superior Finished Product, No Chemical Residues
Your linens will feel and smell fantastic! With all the focus on comfy bedding in hotel rooms these days, why wouldn't you want the outdoor-fresh smell of linens processed in a laundry with a Water Energy Ozone Standard? Stop producing flat, crusty-feeling towels with chemical-smelling residues in your laundry. Ozone is 100% natural and it's Nature's way of cleaning the Earth. Why not insist on it in YOUR laundry? Towels laundered with ozone will be 30 to 50% fluffier. This is because all of the chemical residues that tend to make fibers stick together are eliminated Of course that means you will need more space to store and distribute linens but the bottom line is that your guests will have much fluffier towels to wipe their faces and other body parts with and that will be a better experience for them. Soon, customers are going to demand linens of this quality and greenness. Converting to a Water Energy Ozone Laundry Standard now will put you ahead of the curve and the competition when your guests realize your high-quality linens are the product of an extremely 'green' laundry practice you have adopted in your laundry.
Wash-Cycle Time Reduction = Increased Production (10% - 45%)
The ozone washing system can, almost without exception, reduce the wash-formula time of any laundry facility. In most cases 25%-30% of wash time is spent rinsing or filling and draining the washer while different chemistry is being applied to the linen. Because ozone requires fewer products (and less of the ones that it uses) than does traditional laundering to achieve similar results, wash times can be shortened. This enables facilities to increase the production of the washers. It also increases the useful washer life and reduces the electric energy necessary to produce similar volume.
Shorter Drying Times
Ozone laundry boosts extract efficiency and lowers water retention. Less water in the linens going to the dryers means it takes less time to dry them. This adds up to a huge savings in labor and energy. Water hardness is most often caused by Calcium and Magnesium being dissolved in the water. These dissolved minerals along with Chlorine and other chemicals present in tap water and chemicals used on linens to increase their sheen and to repel soil all cause fabrics to be Hydrophobic. This means they repel water. That's not a good thing when you need to wash them using water. Chemical companies have developed detergents using powerful wetting agents that work well in water having these natural disadvantages. These chemicals cause fabric to act like a water magnet. Although these chemicals have worked well to improve the quality of textile care, they cause more water to be retained in the linen after extraction. More water in the linen means more time and energy are required to dry them.
Dissolved ozone in your wash will eliminate the need for wetting agents and greatly reduce the amount of chemicals you must use. Dissolved ozone acts like a water softener because it breaks surface tension on water. This neutralizes the tendency for water to bead instead of penetrating cloth. This softening effect boosts chemical performance and reduces chemical demand. Ozone also oxidizes or hydrolyzes Calcium and Magnesium which greatly reduces their hardening effect on the water. This greatly boosts chemical performance and reduces chemical demand. (This also greatly reduces the accumulation of minerals in linen which causes them to look dull and dingy over time) Ozone also neutralizes Chlorine and its water-hardening effects. This boosts chemical performance and reduces chemical demand. Fewer chemicals, softer water and no wetting agents mean better rinsing and more efficient extraction. More efficient extraction means less water remaining in the linens. All together this means measurably shorter drying times for your linens and a big savings on labor and energy when you switch to an ozone standard.
Commercial washing machines for years have offered a spin or extract cycle with about a 110 g's of force to extract the water in the linen before sending them to the dryer. As we are so used to in Today's World, things get better over time. Modern washers can provide 350 g's of extraction force and more. This is such an incredible amount of force that it can get your remaining water weight down below 40%. With ozone, the same force can get your water weight down below 20%. Below 20% is better because it gives you the least amount of water to evaporate in the dryers. Your sheets can go directly to the ironer without pre-conditioning first in the dryer - saving more energy. Usually sheets need to go into the dryer for a few minutes to remove enough of the remaining water so they dry thoroughly in an ironer. Water Energy Ozone Laundry Systems deliver all of these drying advantages saving you substantially on labor and energy. It takes 2,000 Btu's to evaporate one pound of water from linens. Most linens coming out of a slow speed extract washer using traditional chemicals will retain at least 80% or more water weight. That means 100 pounds of linens will have at least 80 pounds of water in them. That means your dryer will need to consume a minimum of 160,000 Btu's of energy to get them dry. With a high-speed extract machine using the proper chemicals and ozone you can get out a lot more water. Your remaining water weight would be down around30% which would mean that you would need only 60,000 Btu's or a little more than 1/3 of the energy required in the typical scenario to get your linens dry. Even using ozone with slow-speed extract machines will allow you to reduce your remaining moisture content.
A dryer cycle that is typically 45-55 minutes can be reduced to 27-33 minutes simply by reducing the remaining water weight (water retention) by 1/3. A reduction of 2/3 in water retention would shorten this cycle to below 20 minutes. You can clearly see how a reduction in water weight in linens coming from a washer/extractor will greatly reduce the amount of time and energy required to dry them. A Water Energy Green Laundry System will cut your moisture retention by as much as 75% depending on your laundry's current level of modernization. That's what building a green laundry is all about.
Extension Of Linen Life (25% - 50%)
Degradation of the textile traditionally takes place (1) during routine use; (2) in the wash wheel, where hot water and a variety of caustic chemicals abrade the fabric in the soil removal process; and (3) in the dryer or ironer, where high heat further degrades the textile, especially if there are residual chemicals, such as bleach or alkali, left over after the rinsing process is complete. While ozone washing cannot affect the level of linen degradation that takes place during normal use, it does reduce degradation in the wash wheel and drying processes by curtailing the chemicals placed in the wash wheel and by decreasing the water temperature. Eliminating chemical residue allows more of the water to be released from the fabric in the spin (extraction) cycle of the washer. By reducing retained moisture, the system dries the linen faster at the same temperature (time savings) or at a lower temperature in the same amount of time (energy savings). Specifically, the linen exhibits less chemical residue in the cross-hatching of the textile weave, permitting hot air in the dryer to pass virtually unimpeded through the fabric. Independent laboratory tests on 40 washings in an ozone-processed, heavy-soil formula versus 40 traditional washings have resulted in a more than 50% reduction in fabric degradation.
Huge Labor Savings
Labor is arguably one of if not the most expensive component of any operation including commercial laundry. Many advances have been made over the years in automation technology to speed up a laundry's production rate and reduce the amount of labor required. A Water Energy Ozone Laundry System when integrated properly can drastically reduce the amount of labor required to process linens as compared to traditional methods.
Ozone laundry wash cycles are measurably shorter than traditional wash cycles due to the fact that some of the old, necessary steps in the wash process have been eliminated. This advantage is more thoroughly detailed in the 'Shorter Wash Cycles' and 'Reduced Water Footprint' sections. This reduction in wash cycle times accelerates the work flow and production rate which translates to a savings on labor. The faster you can complete the day's production requirements, the less hours of labor you will need to do it. Water Energy Laundry Consulting and Design relies on its vast experience to specify exactly how to build a laundry facility. Many things must be considered to design a plant that will deliver peak efficiency. One of the most important factors to consider is the orientation and placement of every piece of equipment relative to the rest of the equipment in the laundry. A properly arranged laundry plant will always deliver the highest and most efficient throughput. High efficiency in a laundry will serve to increase PPOH or Pounds per operator hour. PPOH is one of the most important statistics you can calculate for your laundry facility. This value represents just how much linen each operator can do each hour. You take the volume of linen processed, divided by the number of hours needed to process it divided by the number of employees you have doing the work. The higher the number, the higher efficiency you have in your laundry. The higher the number, the lower your labor cost is. PPOH is absolutely a function of how well your laundry is designed. You want employees to be able to accomplish the work with the least amount of movement to do it. This is achieved by strategic placement of the laundry equipment within the laundry and this is achieved by having many years of experience with how to design a laundry for optimum efficiency.
No matter how efficient your equipment is and how much energy you eliminate from the process, your biggest savings by far will always come from reducing the number of hours or amount of labor needed to process your linens. That is a very hard fact. We all know how modern advances help to reduce the amount of labor required to deliver a product. Better equipment and computer controls have enabled companies to provide higher quality products and services with less and less labor. Your laundry is not any different. Labor is your most expensive component.
Water Energy Ozone Laundry Systems only connect to the existing water lines going to your washers. Our equipment can be installed next to the washers or in the next room if need be. We will never drill a hole into one of your washers or connect to any other piece of equipment in your laundry with one of our ozone laundry systems. There will be no recirculating pumps, lint screens or shock-hazard contraptions sitting behind your washers because we don't need them. Our systems deliver active, dissolved ozone to the wash wheel in concentrations of 1.5 to 3ppm and higher where it begins to work immediately. Water treatment is the backbone of the ozone laundry process. The objective is to get the proper dose of dissolved ozone to the wash wheel when needed - at the beginning of the wash cycle. Our ozone laundry systems' primary role is to produce water with a high level of dissolved ozone and have enough of it available at all times to satisfy washer demands. A washer properly outfitted for use with a Water Energy Green Laundry System will have 3 water inlets. One of them specifically for the water with dissolved ozone. When the washer needs more ozone, it opens the valve connected to the ozone laundry system. You teach the washer how to do this when you create the wash programs. This separation of equipment and the laundry room can save floor space in tight laundries and it can give you added security if your laundry is run by people you want to keep away from the ozone equipment.
Ozone is truly a green laundry chemical. Ozone is a clean gas made entirely of pure oxygen which is available all around us. You won't have to store large amounts of hazardous chemicals on site at your facility any more. Big reservoirs of Chlorine, Alkali and Acid are no longer needed because ozone will be doing most of the dirty work. The detergent you use should be a biodegradable surfactant that will easily break down in the environment or can be easily removed by our water reuse system. The use of our ozone laundry system will cause your wastewater quality to go up a million-fold and every living creature on the Planet will be better off for it. High concentrations of dissolved ozone will lead to the creation of Hydroxyl Radicals or OH molecules at a pH as low as 8 instead of the astronomically high 11 normally seen in traditional laundering methods. This fact is the Holy Grail of laundry wastewater treatment. You get an equal or greater amount of cleaning power as with the traditional soup of caustic chemicals without all the chemicals! You only need a tiny bit of alkali to increase the pH enough to create an OH molecule and get your linen clean.
An OH Radical is #2 on the scale of most powerful oxidizers in the Universe. The only compound more powerful is Fluorine gas and it is highly toxic. You could never use it for anything relating to laundry. Therefore, Hydroxyl Radicals are the safest and most effective things to use at removing stains and odors and for killing bacteria and viruses. When a high dose of dissolved ozone is delivered to your wash wheel, you will actually have 4 of the top oxidizers on the list working for you. Hydroxyl Free Radicals, Atomic Oxygen, Ozone and Molecular Oxygen will all be present and active. Ozone is a triple Oxygen (O3) molecule and is highly reactive on its own. As ozone breaks down, it releases a single Oxygen atom (O1) and Molecular Oxygen (O2). These single oxygen atoms instantly bond with the first thing they come into contact with. This means they instantly neutralize stains, odors and biological contaminants. These free Oxygen atoms also bond with Hydrogen Ions provided by the alkali and form Hydroxyl Free Radicals (OH). When you have ozone applied in the proper concentration, you get a quartet of powerful and environmentally friendly agents working together to clean your linens.
Chlorine Bleach oxidizes Carbon molecules much more slowly than and not as completely as Hydroxyl Radicals and ozone. In the process it also creates a dizzying array of toxic chemicals called Disinfection By-Products (DBP's) including Formaldehyde and Chloroform. These DBP's are part of a family of nasty chemicals called THM's or Tri-Halo Methanes (halogenated compounds) that you want absolutely no part of if at all possible. There is no question that these compounds are carcinogenic. Chlorine is also the single most damaging element to the Earth's ozone layer and our use of it should be curtailed wherever possible. The old staple Chlorine is located at #16 down the list of most powerful oxidizers and that's what we've always depended on to get our whites white and our germs killed. The reason people haven't used ozone much before is because it is much harder to generate, dissolve in water and make use of as opposed to Chlorine. You just pour some Chlorine in very hot water and that's it. With ozone, there are many issues to address when using it in your laundry. Our 20+ years of experience working with ozone at NASA and 10+ years working with ozone in the laundry industry has given us the expertise to do it very effectively, efficiently and dependably.
Adopting a Water Energy ozone laundry standard in your laundry will allow you to reduce your total chemical costs by 50% or more. You will eliminate most of your alkali, only use a fraction of the detergent you were using before and do away with Chlorine and acid all together. You don't need the acid because you have eliminated most of the alkali. Normally after you've raised your pH above 11 with plenty of alkali (as described earlier), you would use acid to bring the pH back down to a more hospitable level - one that the public sewer utility will allow you to send down the drain. A wastewater plant operator will not allow you to discharge water with such an extremely high pH without buffering it first with acid. This process is similar to adding acid to a pool to bring the pH down closer to neutral. If laundry plant operators do happen to send these 'spikes' of caustic water down the sewer, certain impact fees or fines could be levied against their laundry. Wastewater from a laundry with a Water Energy Ozone Laundry System is of vastly higher quality than wastewater from a traditional laundry operation and will NEVER incur any impact fees. Elimination of those fees (or the possibility thereof) could pay for your ozone system many times over.
How The Ozone Washing System Works
Closed-Loop (Recycling Process)
The closed-loop ozone laundering system starts at the contact (process) tank, where clean water is injected via ventury with ozone gas, creating microscopic bubbles. A "process" water pump flows these small bubbles into the bottom of the tank; as they rise and make contact with the water; they create an ozone residual in the water. When washing machine signals for water, a transfer pump delivers the ozone-filled water to the washer, where it interacts with the oxidizable soils in the linen. Surfactant and bleach are added according to pre-set formulas from an installed chemical pumping system. The mechanical action of the washer assists in separating the soil from the textile. When the washer drains, the water is collected in the sump or drain area. As the sump fills, a water-level switch activates a sump pump, which delivers the soiled water though a screen or coarse bag filter designed to remove larger particulate (75 micron or larger) and lint from the water. The water then drops into a screen-filter holding tank. A second-level switch in the screen-filter tank activates a transfer pump, passing the water through an automatic back-washing multi-media filter that removes waterborne particulate larger than 20 microns.
The water then flows to the storage tank, which is injected with ozone gas via ventury. The resulting bubbles enter the bottom of the tank. As they rise to the surface, the bubbles float and carry smaller remaining particulate and oil and grease molecules to the tank surface, a process termed "induced air flotation." When the storage tank is full, the particulate and oil film on the water are channeled to a collecting weir, which drains to the sewer. The dissolved ozone in the storage tank's water supply oxidizes odor molecules, viruses, bacteria, and other organic contaminants. Upon demand, a water transfer pump sends water from the storage tank to the contact or process tank and the entire process starts all over again. As water is lost in the system through evaporation and filter back wash, additional water is supplied to the system from the "make-up" water line into the storage tank, which comes from the facility's normal incoming water line. (A water softener may be required if the water is from a well or of the city water supply is over hard.) A computerized diagnostic control panel guides the system, interfacing between the washing equipment and the various pumps, level switches, and other ozone system components. The panel also serves as a troubleshooting center to isolate potential problems in the system for maintenance and repair. Override valves installed at each washer water inlet allow for conventional or ozone washing on any combination of washers. The ozone generation equipment consists of an ozone generator cabinet, an air preparation system that concentrates oxygen from the atmosphere to supply the generator, and an air compressor if needed.
An automatic air quality sensor is installed near each source of ozone generation and is preset to shut down electrical power to the system if any elevations of ozone gas are detected in the ambient air. If this should occur, ozone generation ceases immediately and remaining levels of gas revert back to an oxygen state. This meets OSHA requirement 1915.1000, which states that ozone in the air must be kept to 0.1 ppm.
Open-Loop (Non-Recycling Process)
The open-loop system starts at the incoming water line. The water (softened as needed) enters the contact tank from the facility's water supply. An ozone generator system similar to the closed-loop system delivers ozone gas to the contact tank via ventury injection, forming microscopic bubbles, which are pumped to the bottom of the bank. When the bubbles contact the water, they create a dissolved ozone presence. The ozone-filled water is then transferred to the washer on demand with a transfer pump. At the end of the wash process, the water drains to the sewer. As in the closed-loop system, similar additives are placed in the washer, as needed, particularly in heavy soil situations.
Open and closed-loop ozone washing systems are now in place and processing linen on a daily basis in hotels, prisons, commercial laundries and nursing homes in eight states. More than 40 million pounds of textile have been washed with the systems. Most environmental technologies are extremely capital intensive. While there is certainly a cost associated with implementing ozone-washing systems, in most cases, the return on capital investment can be completed in 8 to 10 months, wholly derived from a combination of savings. In these days of mounting health care costs, the health care administrator needs to look to innovative technologies that reduce overhead while improving quality of service. Ozone washing provides a financially attractive and proven alternative to conventional linen processing while preserving the environment.