Matthew Schnobrich

Stimulating In Situ Hydrogenotrophic Denitrification with Membrane-Delivered Hydrogen under Passive and Pumped Groundwater Conditions

A technology was developed to stimulate autotrophic biological denitrification by supplying hydrogen ( H2 ) to groundwater via gas-permeable membranes. The purpose of this project was to investigate this technology at field scale, determining whether it could be successfully scaled up from the laboratory. The field site was located in Becker, Minnesota and contained high levels of NO 3− ( 22.8±2.0 mg/L-N ) and dissolved oxygen (DO) ( 7±1 mg/L ) . Membranes installed in groundwater wells were successful in delivering H2 to the groundwater over the two-year operating period. Hydrogen stimulated microbial reduction of DO and NO 3− , degrading up to 6 mg/L DO and converting up to 10.0 mg/L NO 3− -N to NO 2− -N when operated passively. When recirculation pumps were installed performance in the field did not improve significantly because of mixing with more oxygenated water. However, complementary modeling studies showed that complete DO reduction and denitrification to N2 was possible but the zone of influence...

Remediation Engineering : Design Concepts, Second Edition

Remediation engineering has evolved and advanced from the stage of being a sub-discipline of environmental engineering into its own engineering discipline supporting the growth of a global industry. This fully-updated second edition will capture the fundamental advancements that have taken place during the last two decades, within the sub-disciplines that form the foundation of the remediation engineering platform. The book will cover the entire spectrum of current technologies that are being employed in this industry, and will also touch on future trends and how practitioners should anticipate and adapt to those needs.