Filtration of natural and colloidal matter is an essential process in today's water treatment processes. The colloidal matter is retained with the help of micro- and nanoporous synthetic membranes. Colloids are retained in a "cake layer"--often coined fouling layer. Membrane fouling is the most substantial problem in membrane filtration: colloidal and natural matter build-up leads to an increas...

AIMS To develop an anti-microbial filter media using an attached quaternary ammonium compound (QAC) and evaluate its performance under conditions relevant to household drinking water treatment in developing countries. METHODS AND RESULTS Silica sand was coated with dimethyloctadecyl [3-(trimethoxysilyl) propyl] ammonium chloride via covalent silane chemistry. Filter columns packed with coated...

In this paper, we characterize the filtration and deposition profiles of a recombinant analog of Norwalk virus, an important waterborne pathogen, in packed beds of saturated quartz sand under both ‘clean-bed’ and ‘dirty-bed’ conditions. Under clean-bed conditions with NaCl as the electrolyte, the retained Norwalk virus particles decline like a power-law with depth. The power-law decay in retain...

Pumice and the Moringa oleifera (MO) seed were investigated as alternative natural materials for drinking water treatment based on problems identified at the Stretta Vaudetto water treatment plant in Eritrea. Lab and pilot scale studies showed that pumice was a suitable alternative material for dual media filtration. Conversion of the sand filters at Stretta Vaudetto to pumice-sand media would ...

The functioning of ecosystems results from the interplay between living organisms and their surroundings. Therefore, our ability to predict eco system functioning depends on our understanding of interactions between dynamic biotic and abiotic variables. Biodiversity can be influenced by the changes in the environment and can also influence ecosystem functioning, but our understanding of how env...

Pharmaceutically active compounds (PhACs) and drugs of abuse (DAs) are two important groups of emerging environmental contaminants that have raised an increasing interest in the scientific community. A number of studies revealed their presence in the environment. This is mainly due to the fact that some compounds are not efficiently removed during wastewater treatment processes, being able to r...

comin the case of pharmaceutical processes, the presence of preservatives can be problematic and the quantity is subject to stringent standards. so, the aim of this study is to quantify the removal of glycerin contained in ultrafiltration flat sheet membranes by filtration and soaking. this is carried out over a wide range of membranes with different characteristics. the selected flat sheet mem...

In petroleum production, Produced Water Re-Injection (PWRI) has earned much interest among disposal methods of the produced water. However, presence of the contaminants in the produced waters usually results in formation damage in well bores and their surrounding fracture systems. In the present study, modeling of external cake formation on a fracture in unsteady-state conditions i...

Continuous exposure to low levels of Cryptosporidium oocysts is associated with production of protective antibodies. We investigated prevalence of antibodies against the 27-kDa Cryptosporidium oocyst antigen among blood donors in 2 areas of Scotland supplied by drinking water from different sources with different filtration standards: Glasgow (not filtered) and Dundee (filtered). During 2006-20...