the precipitation of calcium carbonate by bacteria isolated from submerged fixed-film bioreactorused for the treatment of urban wastewater in both natural and artificial media was studied. however, carbonate precipitation was detected only when the bacteria grow in media added with calcium. precipitation took place rapidly, and crystal formation began 3 d after inoculation and the percentage of...

This paper provides an integrated framework handling discrete events for the biological systems. The living organism involves various conditions including discrete phenomena. To enhance the performance and productivity of biological systems, discrete variables play a significant role in designing and operating the biological facilities such as the bioreactor. This study focuses on the algae gro...

Thiobacillus ferrooxidans was used in fixed-film bioreactors to oxidize ferrous sulfate to ferric sulfate. Glass beads, ion-exchange resin, and activated-carbon particles were tested as support matrix materials. Activated carbon was tested in both a packed-bed bioreactor and a fluidized-bed bioreactor; the other matrix materials were used in packed-bed reactors. Activated carbon displayed the m...

A flow-through biosensor consisting of a fixed bed bioreactor was employed to detect the insecticideparaoxon. Based on the inhibition of organophosphorous insecticide to the enzymatic activity of acetylcholinesterase (AChE), using paraoxon as a model compound, the condition for detection of the insecticide were optimized. The influence of enzyme loading on the packing surface was studied ...

A micro-capillary film has been developed that offers the potential for an at-line analytical tool for rapid aggregate analysis during biopharmaceutical antibody production. A non-porous walled micro-capillary film (NMCF) with cation exchange functionality was demonstrated to act as a chromatography medium that could be operated with high linear fluid velocities and was highly resistant to bloc...

On-site biological treatment has been used for groundwater cleanup from industrial and agricultural chemicals. The pump-and-treat efficiency is controlled by retardation of contaminants by sorption onto the saturated subsurface solids and by the presence of non-aqueous-phase liquids in the aquifer. On-site bioreactors have been widely used for treatment of contaminants such as petroleum hydroca...

the hydraulic characteristic of an up-flow anaerobic sludge blanket fixed film (uasb-ff) were studied by changing two important hydraulic factors that can impact significantly on the hydraulic regime of the uasb-ff bioreactor: the up-flow velocity (vup) and biogas production rate (qg). the analysis of the reactor hydraulic performance was performed by studying hydraulic residence time distribut...