Rotating biological contactor

Schematic diagram of a typical rotating biological contactor (RBC). The treated effluent clarifier/settler is not included in the diagram.

A rotating biological contactor or RBC is a biological fixed-film treatment process used in the secondary treatment of wastewater following primary treatment.[1][2][3][4][5] The primary treatment process involves removal of grit, sand and coarse suspended material through a screening process, followed by settling of suspended solids. The RBC process allows the wastewater to come in contact with a biological film in order to remove pollutants in the wastewater before discharge of the treated wastewater to the environment, usually a body of water (river, lake or ocean). A rotating biological contactor is a type of secondary (biological) treatment process. It consists of a series of closely spaced, parallel discs mounted on a rotating shaft which is supported just above the surface of the wastewater. Microorganisms grow on the surface of the discs where biological degradation of the wastewater pollutants takes place.

Rotating biological contactors (RBCs) are capable of withstanding surges in organic load. To be successful, micro-organisms need both oxygen to live and food to grow. Oxygen is obtained from the atmosphere as the disks rotate. As the micro-organisms grow, they build up on the media until they are sloughed off due to shear forces provided by the rotating discs in the sewage. Effluent from the RBC is then passed through a clarifier where the sloughed biological solids in suspension settle as a sludge.[6]

  1. ^ C.P. Leslie Grady, Glenn T. Daigger and Henry C. Lim (1998). Biological wastewater Treatment (2nd ed.). CRC Press. ISBN 0-8247-8919-9.
  2. ^ C.C. Lee & Shun Dar Lin (2000). Handbook of Environmental Engineering Calculations (1st ed.). McGraw Hill. ISBN 0-07-038183-6.
  3. ^ Tchobanoglous, G., Burton, F.L., and Stensel, H.D. (2003). Wastewater Engineering (Treatment Disposal Reuse) / Metcalf & Eddy, Inc (4th ed.). McGraw-Hill Book Company. ISBN 0-07-041878-0.{{cite book}}: CS1 maint: multiple names: authors list (link)
  4. ^ Frank R. Spellman (2000). Spellman's Standard Handbook for Wastewater Operators. CRC Press. ISBN 1-56676-835-7.
  5. ^ Mechanical Evolution of the Rotating Biological Contactor Into the 21st Century by D. Mba, School of Engineering, Cranfield University
  6. ^ Steel, E.W.; McGhee, Terence J. (1979). Water Supply and Sewerage (Fifth ed.). New York: McGraw-Hill Book Company. ISBN 0-07-060929-2.: 492–493