After primary treatment, wastewater/sewage is sometimes subjected to a secondary biological solid membrane treatment, using rotating biological contactors (RBCs).
Sand and coarse suspended solids are removed by screening as part of the pre-treatment process, and then the suspended solids are sedimented. Before being released into the environment—typically a body of water (river, lake, or ocean), treated wastewater/sewage undergoes the RBC process, which filters out pollutants by contacting it with a biological film.
Objective of rotating biological contactors
Wastewater is cleaned in the Rotating Biological Contactor using disk-mounted membranes. With around 40% of their surface area buried in the wastewater, the disks gently rotate.
Pollutants are broken down aerobically by absorbing oxygen from the air and contaminants from the wastewater. Older bacteria whose activation has decreased fall off the disks, as fresh germs continuously multiply on them.
What is the Process of rotating biological contactors in STP?
1: Microorganisms must have food to grow and oxygen to survive in order to prosper. Oxygen is drawn from the atmosphere while the disc spins. When the microbe develops, it builds up on the medium until it is ejected into the wastewater, by the revolving disc's shear forces.
2: The RBC's wastewater is next processed by a purifier, where sludge is formed when flaky biological particles collect in suspension.
3: Rotating disc packages, often known as "media," revolve between 2 and 5 times per minute in tanks or tabs. Polyethylene, PVC, and Styrofoam are often used plastics for media.
4: A number of packing’s are often connected to create the sewage pipe, and the shaft is positioned so that it rotates at a right angle, to the sewage stream. Wastewater is present on the disk surface to a depth of around 40%.
5: A coating of mucus is formed on the disc's surface as a result of biological growth deposition. As it rotates, the disc exposes wastewater to the atmosphere for oxidation.
6: Rotation aids in loosening surplus solids. Daisy-chaining the disc mechanism allows for practically any level of residence, or removal that is needed.
7: Later phases of culture can get used to progressively decaying materials, thanks to the system's layering.
What components make up rotating biological contactors?
It is made up of several parallel, dense discs that are fixed on a revolving shaft, which is borne slightly above the sewage surface. On the surface of the glass, where biological breakdown of wastewater contaminants occurs, microorganisms flourish. In the case of organic loads, the Rotary Biological Contactor (RBC) can sustain overvoltage.
How does RBC’s attain nitrification of wastewater?
To achieve nitrification of wastewater, the majority of RBC systems have at least four or five modules connected in series. There is a visible color change from grey/beige to brown as the biofilm biomass transitions, from carbon metabolism to nitrification.
The biofilm's gradual transition from grey/beige to brown, from left to right, represents a movement from bacteria that metabolize carbon to those that metabolize nitrogen.
The organic matter in the wastewater, which is measured as BOD-5, is absorbed by the biofilm, a biological growth that adheres to the window. A revolving procedure called aeration is used to help the contaminants removed from the water, decompose by exposing the media to air when it comes into contact with sewage.
The surface area of the medium, along with the kind and volume of incoming wastewater, all affect how much of it is treated.
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We have become a leading manufacturer thanks to the Rotating Biological Contactor's outstanding durability and wastewater purification capabilities. We have created and implemented new technologies in sewage and effluent treatment. For further information, contact us at +91 9650608473 or enquiry@netsolwater.com
