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Environmental engineers tackle the problem of water reuse in Centre County and around the world
Water is our most valuable commodity. It’s a lot easier to get along without gasoline or heating oil than without a consistent supply of clean, safe drinking water. It is generally recognized that the big improvements in human health and life expectancy are due to removal and treatment of wastes and to provision of safe drinking water.
We need at least a few liters of water a day to sustain our bodies, but we also need water for personal hygiene, cooking, and washing. We use about 600 liters per capita per day in the U.S. The number is much smaller in locations where clean water is less available because of poor supply or water quality problems.
Penn
State researchers, Dr. Brian Dempsey, professor of environmental engineering and associate director
of PSIEE; Major Tom Timmes, Ph.D. candidate; and Dr. Hyunchul Kim, visiting scholar from the
Korean Institute of Science and Technology, have been working to develop ways to provide
safe drinking water in difficult environments such as post-Katrina Mississippi or in remote
Army installations. Delivery of water to locations with a damaged or nonexistent infrastructure
is huge problem. Improved water treatment makes it possible to use contaminated local sources
of water and avoid long transports.
The researchers are investigating electro-coagulation along with membrane filtration for an operationally simple but reliable method for removal of chemical and biological contaminants. The technique has several potential advantages: the electrodes are 100% iron or aluminum in a solid form as opposed to 8 to 15% metal in conventional liquid coagulants; coagulant can be accurately dispensed by controlling the current, or energy can be produced along with coagulant by using the electrodes in a battery arrangement; additional purification of water occurs because oxidants are produced during electro-coagulation; and the electro-coagulation floc does a better job of removing the organic materials that frequently foul membrane filters.
The researchers also are finding better ways to recycle and reuse water here in Centre
County, PA. The need for reuse of water in Centre County is driven by environmental concerns.
Local wastewater authorities have a limit on the total discharge to Spring Creek, one the best
trout streams in the country, but the population and economic activity in the area are growing.
Cleaning the water so that it can be reused by local industries is the solution, but this requires
effective and reliable technologies. Kim, Dempsey, and Timmes are identifying the organic components
in wastewater that are most likely to foul membranes, and then devising coagulation strategies
that are good for removal of those components.
Contributed by Brian Dempsey, professor of environmental engineering and associate director of PSIEE; Email: bdempsey@psu.edu.