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Waste acclimation and batch microcosm studies containing digested municipal solid waste were conducted at different temperatures (22, 35, and 45[degrees]C) and gas-phase oxygen concentrations (0.7-100%, by volume) to provide guidance for field-scale implementation of in situ nitrogen removal processes. Results demonstrate that in situ ammonia-nitrogen is feasible in decomposed aerated solid waste environments at the gas-phase oxygen concentrations and temperatures evaluated and the potential for simultaneous nitrification and denitrification in field-scale bioreactor landfills is significant due to the presence of both aerobic and anoxic areas. Small amounts of oxygen were found sufficient for nitrification/ammonia removal to proceed, although removal rates increase with oxygen concentration. Laboratory results suggest field-scale implementation of in situ nitrogen removal occur in small dedicated treatment zones containing previously degraded waste (later in the life of a bioreactor landfill). Model simulations indicate removal of ammonia-nitrogen to low levels can occur with relatively short aeration depths (depth estimates ranged from 1.6 to 7.2 m below the point of leachate injection). Field-scale verification of these depth estimates is required prior to routine acceptance. CE Database subject headings: Landfills; Nitrification; Denitrification; Aerobic treatment; Abatement and removal.

This paper describes the Environments for Fostering Effective Critical Thinking (EFFECTs) pedagogical framework that has been developed and implemented across the civil and environmental engineering curriculum at the University of South Carolina. Thirteen unique EFFECTs have been created to date, impacting seven different courses. This instructional approach has been used in courses at all undergraduate levels, from first-year introduction courses to upper division elective courses. The cumulative application of EFFECTs facilitates the integration of technical and professional skills to meet programmatic student outcomes. This paper provides a map of the ABET and ASCE student outcomes that are addressed with EFFECTs, with appropriate examples from different EFFECTs modules. In terms of professional student outcomes, the EFFECTs framework is designed to enhance student communication skills, teamwork, and knowledge of contemporary issues. In addition to these three core outcomes, each EFFECT can incorporate other professional skills, depending on the nature and content of that particular EFFECT. The implementation of EFFECTs has reached a point where most, but not all, upper division students (seniors) have been exposed to the EFFECT approach at least once during their academic program. Survey results on student self-perceptions of professional skill development are reported in this paper. Based on those findings, teamwork is the highest rated outcome. Professional skill development was also found to improve significantly when students are exposed to EFFECTs in more than one course. [ABSTRACT FROM AUTHOR]

As the exploration of the carbonization of mixed feedstocks continues, there is a distinct need to understand how feedstock chemical composition and structural complexity influence the composition of generated products. Laboratory experiments were conducted to evaluate the carbonization of pure compounds, mixtures of the pure compounds, and complex feedstocks comprised of the pure compounds (e.g., paper, wood). Results indicate that feedstock properties do influence carbonization product properties. Carbonization product characteristics were predicted using results from the carbonization of the pure compounds and indicate that recovered solids energy contents are more accurately predicted than solid yields and the carbon mass in each phase, while predictions associated with solids surface functional groups are more difficult to predict using this linear approach. To more accurately predict carbonization products, it may be necessary to account for feedstock structure and/or additional feedstock properties. [ABSTRACT FROM AUTHOR]