A well water ozone treatment system for the removal of iron, sulfur, and manganese is constructed with three main components. Because ozone is simply a gas that accomplishes the oxidation process, we refer to it as the “ozone system” rather than just “ozone”. These three components include oxidation, aeration, and filtration.

Ozone Treatment Process

Oxidation/injection of ozone is the first step. Oxygen with triatomic atoms has a very high oxidizing power. The chemical reaction produces this gas from air and electric current. Tiny bubbles of ozone are created when ozone is injected into the water, covering every drop in ozone. An immediate oxidation of iron, sulfur and manganese also occurs at this point. A device that produces ozone is the ozone unit (ozone generator).  

Following the production of ozone, the water must be injected with the gas. There are mainly two methods that are typically employed:

1) Ozone Pump – a positive displacement injector that pumps ozone directly into the water, just as chlorine gas is introduced into water through chemical feed pumps

2) Venturi – a device that restricts flow and pressure in order to create a vacuum. Ozone gas is drawn into the water by this vacuum device. It should be noted that insufficient ozone suction will lead to insufficient oxidation due to incorrect sizing.

The second step is aeration. A process of ozone stripping eliminates ozone as well as other gases and odors, such as sulfur. The off-gas tank strips the incoming water of any gas by ozonating the water as it flows down. 

Filtration is the third step. Once the oxidized material has been removed, filtration is the final step. Low water waste (backwash), high service flow, high filtration capacity, and no chemical regeneration are the characteristics of the media to be used.

Ozone Pump vs. Venturi

Injection of ozone into water is only possible using two methods: an Ozone Pump or Venturi. Both methods have advantages and disadvantages.

Ozone Pump

As stated earlier in the article, the ozone pump pumps ozone gas into water via a positive displacement injector that is similar to the chlorine feed pump. The flow and pressure are not restricted, and the volume of gas injected is the greatest.  

Venturi

Before selecting the correct Venturi, you must determine the exact flow rate and recovery pressure of the ozone gas. A poorly sized ozone suction system will lead to an insufficient amount of oxidation, resulting in carry-over of what you are trying to get rid of.

Iron, sulfur, and manganese cannot be removed unless they are oxidized. In order to increase effectiveness, booster pumps increase the pressure prior to the Venturi. However, the disadvantages of having booster pumps include an increase in cost, increased electrical consumption, and noise.

Advantages and Disadvantages of Ozone Pump and Venturi

Venturi

Advantages – Their low cost, lack of moving parts, and low maintenance makes them a great choice.

Disadvantages – A venturi must be sized correctly based on the flow rate and pressure. If not sized properly, ozone injection will be inadequate. Venturis need to be installed in specific locations, before the pressure tank and near the pump. If the venturi is installed in the wrong place, it will not create the proper suction. It is common for pressure and water volume to be lost, which can be extreme. Booster pumps are frequently required, depending on the hydraulics of the system.

Ozone Pump

Advantages – Any location can be injected using Ozone Pumps. As a result of Henry’s Law of Physics, they inject microbubbles in high concentrations at the desired location. With the Ozone Pump, you don’t have to worry about improper sizing or restrictions associated with Venturi and you can inject 2.5 to 4 times as much gas by volume. This eliminates improper sizing and restrictions associated with Venturi.

Disadvantages – In addition to the cost of the machine, moving parts must be replaced periodically. This must depend on the length of time it has been operating and the environmental conditions.