Abstract
Recent research has identified that the major fraction of chemical oxygen demand in domestic wastewaters is in particulate form. The research presented herein develops the kinetics of particle removal as a response to bioflocculation at the surface of aerobic biofilms. This study focuses on the removal of particles that are maintained in aqueous suspension after 30 minutes of gravity settling. It is helpful to consider the particulate organics removal process in biofilms as the sum of four steps, namely (1) external transport of the particles to the biofilm surface, (2) bioflocculation, (3) organic particulate hydrolysis, and (4) diffusion and reaction of the solubilized organics by the bacterial cells comprising the biofilm. Organic (native corn starch) and inorganic particle (Min-U-Sil 10 [U.S. Silica Company, Berkeley Springs, West Virginia]) suspensions, with micronutrients, were continuously fed to a rotating disc biofilm reactor to verify a first-order kinetic expression that has been used to describe bioflocculation and to demonstrate that bioflocculation is the primary particle removal mechanism. Extracellular polymeric substances were extracted and quantified to describe the role they play in the bioflocculation process.
Original language | English (US) |
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Pages (from-to) | 725-735 |
Number of pages | 11 |
Journal | Water Environment Research |
Volume | 79 |
Issue number | 7 |
DOIs | |
State | Published - Jul 2007 |
Externally published | Yes |
Keywords
- Biofilm
- Bioflocculation
- Extracellular polymeric substances
- Kinetics
- Particles
- Particulate chemical oxygen demand
- Suspended solids
- Wastewater
ASJC Scopus subject areas
- Environmental Chemistry
- Ecological Modeling
- Water Science and Technology
- Waste Management and Disposal
- Pollution