State Water Resources Research Institute Program
Project ID: 2009AK79B
Title: Effect of raw water quality and membrane characteristics on membrane fouling and effluent quality for filtration of surface water with high organic matter content
Project Type: Research
Start Date: 3/01/2009
End Date: 2/28/2010
Congressional District: AK-1
Focus Categories: Treatment, Surface Water, Water Quality
Keywords: membrane filtration, DOM, fouling surface water
Principal Investigator: Schiewer, Silke (University of Alaska Fairbanks, WERC (Water & Environmental Research Center))
Federal Funds: $ 19,935
Non-Federal Matching Funds: $ 8,182
Abstract: In recent years, the use of membrane filtration for drinking water production has increased. Membrane filtration has the advantages of providing effective treatment with high product water quality in a compact setup with very few treatment steps. Especially if the source water has a high content of organic matter, a further advantage of membrane filtration is the reduced potential for the formation of disinfection byproducts, harmful substances that are formed during the reaction of chlorine with organic matter. However, membrane filtration suffers from fouling that can be caused by organic matter present in the raw water.
The goal of the present study is to better understand how properties of the raw water such as pH, ionic strength, concentration of calcium and DOM are related to membrane fouling and to the product water quality. This knowledge will make it possible to use membrane filtration in an effective way, e.g. by choosing the optimal type of membrane, selecting a suitable raw water source, and designing pre-treatment processes if necessary. Overall, this research will facilitate the use of membrane technology in areas with limited source water quality.
For this purpose, experiments are conducted at the pilot and laboratory scale. An existing operational pilot scale treatment plant at Toolik Field Station will be used. Source water and product water quality will be sampled during several field trips in the summer of 2009. The collected water will be characterized in the laboratory and be used for additional laboratory membrane filtration tests with and without modifications of the water. Through this integrated approach scale up of lab results to larger scale will be facilitated.
In laboratory studies, several parameters will be systematically varies such as the type of membrane and water quality. The water samples collected in the field will be modified by changing the pH, ionic strength, and calcium concentration. By removing certain size classes of organic matter their contribution to the overall fouling can be characterized.
The results will be analyzed with the help of appropriate statistical techniques and models.
Recommendations will be made regarding the suitability of surface waters for micro-filtration-based drinking water production. Pretreatment options and suitable membrane types will be recommended for different raw water types.
Progress/Completion Report, 2009, PDF