Thursday 9:30 Michael R. Silsbee, Ph.D., RJ Lee Group, Inc.
A Novel Corrosion Inhibitor for Steel in Concrete Derived from Acid Mine Drainage Sludge
Michael Silsbee, Ph.D.
Acid Mine Drainage (AMD) degrades the quality of water over wide areas of Pennsylvania, West Virginia and Maryland. A common method for dealing with AMD is to neutralize the acid using calcium. Corrosion of steel-reinforced concrete is a major factor that degrades infrastructures. Pennsylvania has more bridges than any other state, hence its highway system is particularly susceptible to the effects of corrosion. Based on a technology developed by Chemydration, LLC, RJ Lee Group, Inc. has confirmed that sludge from (AMD) can serve as a raw material for a corrosion inhibitor that materially increases the service life of concrete. While the composition of the corrosion inhibitor is proprietary, it acts to intercept chloride before the chloride can reach the reinforcing steel and facilitate corrosion. For this reason the inhibitor exhibits performance superior to presently available corrosion inhibitors, such as calcium nitrite. This presentation will discuss aspects of processing the sludge as a raw material, pyro-processing of the sludge to manufacture the corrosion inhibitor and the performance of the corrosion inhibitor in concrete. A preliminary design for a manufacturing facility will be described. Initial estimates show that the market for this corrosion inhibitor in new construction alone could exceed 20,000 tons per year. Dewatered AMD sludge typically has a 20 wt. % solids content translating to 100,000 tons of dewatered sludge consumed each year. The market in repair and rehabilitation has been conservatively estimated as 10 times as large. Thus, production of the corrosion inhibitor potentially offers a large volume use for AMD sludge.
Dr. Michael Silsbee assists with the ongoing efforts to develop new products for the construction industry at RJ Lee Group, Inc. He manages projects involving the evaluation of construction materials, mainly focusing on concrete related projects. Previously, Dr. Silsbee had managed the laboratory facilities at the Materials Research Laboratory at Penn State University. He has worked for the past twenty years investigating cementitious and ceramic materials, which include various techniques to characterize powders. In 1996 Dr. Silsbee and a colleague at Penn State developed an approach to dealing with acid mine drainage that allowed a Pennsylvania firm to win a Governor’s Award for Environmental Excellence. Their work on acid mine drainage abatement was a key factor in Tobyhanna Army Depot winning a Secretary of Defense Environmental Security Award in 1996. More recently Dr. Silsbee was part of the commonwealth’s dirt and gravel road task force that won a second Governor’s award for Environmental Excellence in 2000. Dr. Silsbee also established and served as the first director of the Dirt and Gravel Road center at Penn State. Dr. Silsbee holds a BS degree in Ceramic Engineering from Alfred University and a PhD degree in Solid State Science from Pennsylvania State University.