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Treatment Process
First Stage Treatment is also known as preliminary treatment.
Bar Screens
There are two bar screens that have 5/8 inch openings and six feet width. The bar screens remove materials that flow into the sewer system with the wastewater, such as:
- Bottles
- Cans
- Paper
- Plastic
- Rocks
- Etc.
Parshall Flume
After screening, the wastewater goes through a four foot measuring device called a Parshall Flume. The flow is measure to adjust the treatment means in the plant. From here, the abrasion to the pipes and valves in the treatment system.
Secondary Stage Treatment is a form of biological treatment in the oxidation ditch.
Oxidation Ditches
There are two oxidation ditches with an approximate capacity of 8.42 million gallons with an average detention time of 13.5 hours at an average flow rate of 15 million gallons per day. Bacteria are the biological means used to remove organic material, ammonia and phosphorus. Four aerators with 150 horsepower motor turn turbine like impellers to add oxygen and velocity to the micro organisms in the water.
Clarifiers
Five clarifiers perform a liquid/solid separation. The clarifiers also use physical means. They are 12 feet in depth and 100 feet in diameter. The clarifiers have a total capacity of 3.52 million gallons. Overflow from the clarifiers goes to the Third Stage of Treatment.
Rapid Sand Filtration
Rapid Sand Filtration filters the clarifier effluent through sand media and porous plastic plate. There are 6 filters that are 62 feet in length and 16 feet wide and approximately 11 inches of media. This media is very similar to sand on the beach.
Ultraviolet Disinfection
After the third stage treatment, wastewater is disinfected through ultraviolet disinfection. There are 1,312 light bulbs submersed in water and having a wavelength of 253.7 nanometers that penetrates cell walls of bacteria that can cause diseases. This type of treatment disrupts the DNA change thus killing the microorganisms and disinfecting without harming the environment through the use of harsh chemicals.
Bio-Solids / Sludge Dewatering
Also, bio-solids or sludge dewatering is conducted with 2 belt presses, approximately 2 meters wide and operated 6 hours daily.