Air Disinfection

How does Ozone work?

After much research, the coronavirus responsible for the current pandemic is known to spread mainly from person to person through respiratory droplets. The greatest spread of respiratory droplets usually occurs when a person sneezes or coughs. Infected droplets land in the noses or mouths of uninfected individuals, causing the lungs to take in the virus immediately. Due to this method of transmission, COVID-19 is spreads mostly when people are in close contact with each other. The CDC has recently determined that the coronavirus does not typically spread on contaminated surfaces although it is not impossible.

Based on the CDC’s statements regarding the coronavirus’ airborne method of transmission, an HVAC system, either specified or retrofitted with an air disinfection and purification system, could help reduce dangerous, airborne pathogens. There are many variables involved in altering existing HVAC systems that will impact the efficacy of the presented technologies.

Another method to improve indoor air quality and reduce airborne pathogens is to increase outside airflow and/or increase the number of air change rates. These two alternatives were not considered in this system design since most HVAC systems typically do not have the heating and cooling capacity to increase supply or outside airflow. This brochure focuses on “add-on” upgrades to existing HVAC systems.

What is Ozone?

Ozone (O3), sometimes called “activated oxygen,” contains three atoms of oxygen rather than the two atoms we normally breathe. Ozone is the second most powerful sterilant in the world and can be used to destroy bacteria, viruses and odors. Interestingly, ozone occurs quite readily in nature, most often as a result of lightning strikes that occur during thunderstorms. In fact, the fresh, clean, spring rain smell that we notice after a storm most often results from nature’s creation of ozone. However, we are probably most familiar with ozone from reading about the “ozone layer” that circles the planet above the earth’s atmosphere. Here ozone is created by the sun’s ultraviolet rays. This serves to protect us from ultraviolet radiation.

Ozone can be either good or bad, depending on where it is found in the environment.
  • Bad ozone: You may have heard of ozone being in the Earth’s lower atmosphere, near the surface level of the ground. One way that ozone is developed is when emissions by chemical plants, industrial boilers, power plants, vehicles and other sources react in the presence of sunlight. Thus, ozone at ground level is a pollutant, part of what is more commonly known as smog.
  • Good ozone: Approximately 6-30 miles above the Earth’s surface, our Earth has a protective ozone layer that shields us from the sun’s harmful ultraviolet rays. Man-made chemicals are known to destroy this beneficial ozone to us. Hence, in 1987, the U.S. along with over 180 countries adopted a treaty called the Montreal Protocol to phase out the production and use of substances that can deplete the ozone layer.

Link to full article from KXAN Austin view

How does Ozone work?

The third oxygen atom of ozone is extremely reactive because it is unstable. This atom readily attaches itself to other odor molecules. When contaminants such as odors, bacteria or viruses make contact with ozone, their chemical structure is changed to less odorous compounds. As more ozone attacks the remaining compounds, the odor is eventually destroyed. This process is called oxidation. Ozone essentially reverts back to oxygen after it is used. This makes it a very environmentally friendly oxidant.

Ozone not only destroys bacteria cells, but it does it without leaving a residual affect.

How is Ozone produced?

There are basically two methods of producing ozone:

  • Corona Discharge
  • Ultra-violet

Corona discharge creates ozone by applying high voltage to a metallic grid sandwiched between two dielectrics. The high voltage jumps through the dielectric to a grounded screen and in the process, creates ozone from oxygen present in the chamber. This also occurs naturally during lightning storms.

Ultra-violet (UV) light creates ozone when a wavelength at 254 nm (nanometers) hits an oxygen atom. The molecule (O2) splits into two atoms (O) which combine with another oxygen molecule (O2) to form ozone (O3). This also occurs naturally through the sun rays.

How long does Ozone last?

As soon as ozone is formed in a generator and dispersed in a room, some of it reverts back into oxygen (O2). This step occurs by several processes including the following:

Oxidation reacts with an organic material such as odors or smoke. Reactions with bacteria etc., which again consumes ozone by oxidation reactions.
Additionally ozone breaks down thermally. Higher temperatures destroy ozone quicker than lower temperatures. The ozone that remains is referred to as Residual ozone. “Residual” ozone created will return to oxygen usually within 30 minutes, in amounts equal to half its level. What this means is that after each subsequent 30 minute period there would be half as much residual ozone left at the end of the period as was present at the beginning of the period. This is similar to a geometric progression of 16; 8; 4; 2; 1. In practice, the half life is usually less than 30 minutes due to temperature, dust and other contaminants in the air.

Therefore, ozone, while very powerful, doesn’t last long. It does its job and then disappears back into safe oxygen.

How does Ozone Solutions' equipment work?

Ozone Solutions designs and manufactures ozone generators that incorporate the most sophisticated technologies available. Ozone Solutions offers one of the largest ranges of ozone generators in the market. From the small residential scale to large remediation trailers, these systems are sure to exceed your expectations. All Ozone Solutions’ systems have a variety of technical features developed to simplify installation and maintenance and offer the best integration into your current process.

Our knowledgeable staff provide services that utilize both corona discharge and ultra violet ozone generators for odor, surface decontamination, germ and bacteria removal. This gas is considered the most powerful oxidant for disinfecting water or sanitizing surfaces. As part of our services, we use our scientific calculations to determine ozone dosage based on several factors (temperature, flow rate, etc.).

Ozone effects on Pathogens
How does Ozone kill bacteria?

Ozone kills bacteria by destroying the cell wall of the bacteria. Once the cell wall is destroyed, the bacteria will be unable to survive. For more details, please check out our page on the Effect of Ozone on Bacteria.

Industrial Applications
  • HVAC Applications:
    The yield of any grains or feeds is hindered by mold growth, aflatoxins, vomitoxins, insects, and much more. Ozone is a chemical-free solution to these problems that will significantly reduce, or eliminate their presence to meet regulations and increase profitability.
  • Zoo and Aquaculture Applications:
    Ozone is used in aquaculture, and zoos, due to its numerous advantages over traditional water treatment methods.
  • Biofuel Applications:
    Ideal for additional uses in the biofuel industry, including CIP (Clean in Place), exterior pipe washing / general area cleaning, and HVAC systems.
  • Cooling Tower Applications:
    Ozone has been proven a valuable tool as a biocide for the treatment of industrial and utility cooling water systems.
  • Livestock Applications:
    Clean ozonated water improves water consumption, animal growth, and reproduction while lowering the number of illnesses and deaths. Ozone dissolved in cold water destroys organic matter such as bacteria and viruses.
  • Dairy Applications:
    Ozone dissolved in cold water destroys organic matter such as bacteria, viruses, milk solids, and calcium layers. There is no need for thermal energy or chemicals, resulting in no residuals.
  • Grain & Feed Remediation:
    The yield of any grains or feeds is hindered by mold growth, aflatoxins, vomitoxins, insects, and much more. Ozone is a chemical-free solution to these problems that will significantly reduce, or eliminate their presence to meet regulations and increase profitability.
  • CIP (Clean in Place) Systems:
    Ozone is an environmentally friendly disinfectant that leaves no residual, or by-products. Ozone is a safe sanitizer with no need for chemical storage, or handling, thus eliminating the related safety issues.
  • Hydraulic Fracturing Applications:
    When utilizing ozone in groundwater remediation, the ozone is injected into the groundwater to oxidize most of the hydrocarbons (such as Benzene, Toluene, Xylene, and Ethylbenzene) into carbon dioxide, water, and oxygen. Utilizing Ozone Solutions’ industry leading technology onsite typically reduces treatment time by 25% to 85% depending on site conditions.
  • Pools, Spas, Waterparks & Spas:
    Ozone is an effective disinfectant killing bacteria, viruses, spores, mold, and algae. Ozone can be used alone to treat pools and spas or can be combined with sodium bromine to provide a residual in pools that are not continuously recirculated.
  • Pulp & Paper Mills:
    Ozone is considered, from an ecological point of view, to be the best candidate for the bleaching of both hardwood and softwood pulp by replacement of chlorine, in a combination-competition approach with other bleaching chemicals, such as chlorine dioxide, hydrogen peroxide, and per-acetic acid.
  • Semiconductor Production:
    For decades now, semiconductor industry researchers have investigated the use of ozone for wafer-cleaning and resist-stripping applications. To lower chemical consumption and disposal costs as well as to improve cleaning efficiency, ozone has been used as an alternative to traditional cleans using basic (SC-1) and acidic (SC-2) hydrogen peroxide mixtures.
  • Surface Sanitation:
    Not only can ozone be used to sanitize the surfaces of your facility and equipment, but it can also be used to disinfect the surfaces of your products, produces, and meats. You can properly sanitize your surfaces with both gas and aqueous ozone.
Research on Ozone Disinfection