Sewage treatment by a low energy membrane bioreactor.

A new membrane bioreactor (MBR) was developed for treatment of municipal wastewater. The MBR was mainly made up of an activated sludge reactor and a transverse flow membrane module, with an innovative configuration being in application between them. As a result, the transverse flow membrane module and low recirculation flow rate created advantages, such as lower energy consumption and more resistance to membrane fouling.

Addition of anaerobic tanks to an oxidation ditch system to enhance removal of phosphorus from wastewater.

The oxidation ditch has been used for many years all over the world as an economic and efficient wastewater treatment technology. It can remove COD, nitrogen and a part of phosphorus efficiently. In the experiment described, a pilot scale Pasveer oxidation ditch system has been tested to investigate the removal of phosphorus from wastewater.

Transformation of carbon tetrachloride in an anaerobic packed-bed reactor without addition of another electron donor.

Carbon tetrachloride (52 microM) was biodegraded for more than 72% in an anaerobic packed-bed reactor without addition of an external electron donor. The chloride mass balance demonstrated that all carbon tetrachloride transformed was completely dechlorinated. Chloroform and dichloromethane were sometimes also found as transformation products, but neither accumulated to significant levels in comparison to the amount of carbon tetrachloride transformed.

Partially oxidized polycyclic aromatic hydrocarbons show an increased bioavailability and biodegradability.

Polycyclic aromatic hydrocarbons have a low water solubility and tend to adsorb on soil particles, which both result in slow bioremediation processes. Many microorganisms, known for their ability to degrade polycyclic aromatic hydrocarbons, only partially oxidize these compounds. White rot fungi, for instance, convert polycyclic aromatic hydrocarbons to more water soluble and bioavailable products.

Performance of a styrene-degrading biofilter containing the yeast Exophiala jeanselmei.

A general mathematical model developed for a description of pollutant degradation in a biofilm was used to evaluate the performance of a biofilter for the purification of styrene-containing gas. The biofilter contained perlite as an inert support on which a biofilm was present composed of a mixed microbial population containing the fungus Exophiala jeanselmei as a major styrene-degrading microorganism. Although styrene is a moderately hydrophobic compound, the biofilter was reaction limited at a styrene gas phase concentration of 0.