How to Select the Right-Sized Ozone Generators

Seeking guidance on sizing your ozone system and comprehending ozone generators? This informative article offers valuable insights to help you choose the appropriate ozone generator, calculate the required ozone amount, establish the ideal ozone concentration, and determine the optimal ozone exposure time for your needs. Should you require further assistance in selecting an ozone generator, our friendly team is readily here to provide expert support.

Ozone Generator

An ozone generator is a device that generates ozone by dissociating oxygen (O2) molecules into individual atoms, which then combine with other oxygen molecules to create ozone (O3). The equipment functions by applying an electrical charge to the oxygen molecules (O2) as air flows through it, resulting in the temporary separation and recombination of oxygen atoms with other oxygen molecules, thereby producing ozone (O3). In some cases, the ozone generator may also utilize an oxygen concentrator to feed enriched oxygen, leading to higher concentrations and increased ozone production.

Plasma Ozone Generators are commonly used for industrial ozone generation. Operating on the principle of dielectric barrier discharge, these generators ionize oxygen gas through an electrical charge until it reaches a conductive state, resulting in the formation of Plasma. Through this process, Plasma ozone generators can produce ozone gas at concentrations ranging from 10 to 15%.

Ozone generators are classified based on their ozone production, measured in grams per hour (or pounds per day). You can find smaller units with nominal ozone production starting from 15 g/h, while more powerful ones can generate up to 200 g/h. It is crucial to understand that the amount of ozone produced in a specific time period can vary significantly depending on the oxygen flow rate. For instance, the production of 15 g/h of ozone with an oxygen flow rate of 4 LPM will result in a higher concentration compared to the production of 15 g/h with a flow rate of 12 LPM. Therefore, knowing the ozone concentration is essential. If a performance table is absent, it might indicate that the ozone generator is not performing well. Ozone concentration is measured as the ratio of total feed gas to ozone production, expressed in g/m³ or wt%.

Ozone Mass Transfer

Ozone mass transfer involves the transfer of a gas phase into water. In most ozone applications, ozone needs to be dissolved in water. Ozone gas is only partially soluble in the liquid, but high mass transfer efficiencies can be achieved through proper methods and equipment. Two common methods for transferring ozone to water are bubbling and using a venturi mass transfer system. Initially, diffusion stones were commonly used for transferring ozone mass to water, but currently, venturi-based mass transfer systems are preferred due to their simplicity, cost-effectiveness, and effectiveness. A venturi injector can reach about 90% efficiency and even up to 99% efficiency at dissolving ozone into the water.

Select the Right Size Ozone Generator

To determine the appropriate size of an Ozone Generator for Water Treatment, the following information is essential:
● Water Quality and Ozone Demand (via Water Sample Analysis)
● Choose the Right Ozone Dosage
● Flowrate
● Inline Pressure
● Water Volume for recirculating systems

Water Quality and Ozone Demand

In order to effectively remove contaminants from water using ozone, it is crucial to consider how the amount of ozone required is influenced by the ozone demand. Since ozone is non-selective, it reacts with various "contaminants" in the water, impacting the necessary ozone dosage. To ensure the correct dosage is applied, an analysis of the water sample is necessary. For your reference, the following are the typical demand required for different contaminants.
Iron: 0.14 to 0.50 mg/l
Manganese: 0.88 mg/l
Hydrogen Sulfide: 3.0 mg/l
The ozone dosage required per mg/liter of contaminant is as follows. This figure must be added to the target dosage to ensure sufficient ozone is used for effective treatment:

DOSAGE

Dosage refers to the required amount of ozone, and it is commonly expressed in mg/l or ppm. Both values are equivalent.
Various applications necessitate different dosages of ozone as shown in the following:
Bottled water: 0.05-0.3 ppm
Cooling towers: 0.05 – 0.3 ppm
Reclaimed water: 0.2 – 0.5 ppm
Bacteria & Virus: 0.2 – 1.0 ppm
To calculate the ozone dosage (g/h) for single-pass applications, simply multiply the dosage required by the contaminant level by the flow rate.
As an illustration, if the dosage required is 2 ppm, the contaminant level (demand) is 8 mg/l, and the flow rate is 4000 liters per hour:
2 (mg/l) x 8 (mg/l) x 4000 (l/h)
= 64000 (mg/h) + 25% safety factor
= 80000 (mg/h)
= 80 (g/h)
There are two critical points to consider. Firstly, ozone in an aqueous solution undergoes self-decomposition, which is temperature-dependent. To illustrate, for every additional 6 degrees in water temperature, you should add 25% more ozone. For further details on sizing ozone equipment for your pool and how to compensate for the half-life of ozone in water, as well as the half-life of ozone, please refer to the provided link.
Another important aspect is that it is not feasible to dissolve all the ozone produced in water. The mass transfer efficiency increases with higher ozone levels. For instance, if you need 8g/h of ozone dissolved in water, it does not necessarily mean you require an 8 g/h ozone generator. An air-feed ozone machine generates ozone at low concentrations, which may not be beneficial for industrial applications. Hence, it is crucial to select a high-performance ozone generator to achieve the desired results.

Ask Sihon-Ozone for Help

Please feel free to Reach Out to Us for further information on how to properly size ozone equipment for your specific needs. Welcome to visit Sihon-Ozone and check our Ozone Generators. There, you will find a wide range of types for a wide range of ozone applications. No matter how demanding your purchasing needs are, I believe you will find what you need there. Our team will be glad to assist you and provide the necessary guidance.