VOC is the abbreviation of Volatile Organic Compound. In a general sense, it refers to all volatile organic compounds. But in the sense of environmental protection, it refers to a class of volatile organic compounds with active chemical properties. They are also the kinds of VOC that can cause harm to human health. All VOC are organic compounds with high vapor pressure at room temperature that can participate in atmospheric photochemical reactions. They can be aromatic hydrocarbons, hydrocarbon or aldehydes, etc. Formaldehyde that we all know is a type of VOC. In addition, VOC also includes benzene, toluene, n-butyl acetate, ethylbenzene, styrene and other compounds. Although these compounds have different chemical properties, one thing they have in common is that they all cause environmental problems and can have a significant impact on human health. Faced with VOC problems, there are many ways to deal with them. But among these methods, VOC removal with ozone is the topic that we will talk about today. We believe that ozone treatment is currently the best solution to the VOC-related problems. Please read on and learn why.

Sources and Hazards of VOC

The main source of VOC is divided into two types, namely outdoor and indoor. The outdoor source of VOC is mainly automobile exhaust, while indoor VOC mainly comes from coal and natural gas combustion, smoking, kitchen odors, the introduction and use of building materials, furniture and chemical cleaning products. When the VOC content in the living environment reaches a certain amount, it will lead to headache, nausea, fatigue, vomiting and other symptoms. In serious cases, VOC can also cause coma and convulsions, damage the liver, kidney and nervous system, and cause memory loss.

Among the sources of VOC mentioned above, the most closely related to our daily life is the presence of VOC in construction, decoration materials and interior coatings. It is estimated that 4.3 million people worldwide die from indoor air pollution each year, and a large proportion of these deaths are due to VOC. In addition to the above problems, the prevalence of VOC increases the risk of leukemia in humans. In particular, the effects of VOC on the health of infants may be greater than that of adults. This is because infants spend more time in their rooms than adults, and their liver, kidney and nervous systems are more vulnerable than adults.

Advantages of VOC Removal with Ozone over Other Methods

Common VOC treatment methods include active adsorption with activated carbon, diatomite, zeolite, high-altitude emission, combustion, biological treatment, HAP solvent method and the solution with ozone.

Activated carbon, diatomite, zeolite and other materials have good adsorption effect on VOC molecules. But these active adsorption methods involve the replacement of the materials at a regular basis, which results in a high maintenance cost. Part of the exhaust gas containing VOC emitted from high altitude will finally return to the ground due to airflow. In biological treatment, VOC treatment demands the construction of a large number of biological filters. This would require a long construction cycle and a huge economic cost. The use of HAP solvents can realize the prompt construction of the treatment facilities. But what is well known is that HAP solvents contains toluene, xylene and other harmful components. They will cause secondary pollutions.

Compared with the above treatment methods, VOC removal with ozone will take the treatment to a new level. For more information about Ozone, please refer to our Blog: An Introduction of Ozone. The strong oxidization of ozone can play an important role in the elimination of VOC in indoor environment. Moreover, compared with other methods, ozone solution has several significant shining points, which are mainly reflected in the following aspects:

• Ozone exists in the form of gas. So, it can be easily piped to many places where it will be used.
• An ozone generator, which is the generating equipment of ozone, does not need to be placed into the treatment environment. It can be isolated from the environment to be treated. By doing this, the reaction between the high-pressure arc generated during the use of ozone generators and VOC molecules in the air can be prevented from happening. This will help to ensure the safety and stability of the operation.
• Ozone is suitable for the removal of VOC molecules in humid gas. When ozone is dissolved in water within the air, hydroxyl radicals will be produced, which are highly oxidizing. This helps to achieve a better removal effect by ozone.
• Compared with other methods, VOC removal with ozone is also more economical and environment-friendly. It can be used for as long period of time as months or even years. Even a small amount of ozone can achieve a better treatment effect than other solutions. And no residues will be produced in the treatment process.
• Ozone gas dehydrated by driers can significantly reduce the maintenance cost of the equipment. With the hydration treatment, the equipment can guarantee a stable operation for several years.

VOC Removal with Ozone and UV

If higher requirements for VOC removal are required, then additional means of treatments can be applied to optimize the process. And UV is one of the most common additional treatment means. UV can react with ozone and produce hydroxyl radicals. Hydroxyl radicals react more actively with VOC molecules. In addition, there will be chain reaction in the process of VOC treatment with hydroxyl radicals, which can improve the oxidation of VOC molecules.

In addition to VOC, ozone also has a good effect on the treatment of chemical odors in the indoor environment. For details, you can refer to our previous Blog: Keep Away from Chemical Odors with Ozone. Ozone has a wide range of applications in odor removal, sterilization and water treatment, etc. You can go to our Ozone Applications to learn more.