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1	High-Temperature Steam Gasification of Agricultural and Municdipal Solid Waste and Converstion to Energy System Skip Ingley, Jacob N. Chung University of Florida The University of Florida researchers will conduct a one-year project researching the feasibility of high temperature (super-critical) steam gasification of municipal solid waste (MSW) and Florida farm biomass waste. The research will center on the use of a bench scale gasifier which was just recently used to investigate the high temperature steam gasification of woody biomass as the feedstock. This new research effort will allow the researchers to investigate the use of MSW and farm biomass feedstock resources to produce synthetic fuels. This innovative high-temperature steam gasification research with MSW and farm biomass will provide a platform for the demonstration of these renewable energy technologies and establish their commercial feasibility. The bench scale gasification system is comprised of several modules including a biomass/MSW material handling module, an innovative, state-of-the-art high-temperature steam generation module, several gasification modules (interchangeable) and a gas clean-up and residual collection module. The researchers will conduct experiments with the bench-scale gasifier using synthetic mixtures of typical MSW and farm wastes. The composition of gasifier outlet stream will be analyzed for several operational conditions to determine the effects of feed composition on the gasification products. A gas chromatograph/mass spectrophotometer will assist the researchers in quantifying the effluent gas stream from the gasifier. This study will address many of the technical, economic, and environmental challenges in the process of utilizing biomass fuels. The project demonstrates a unique innovation of using super critical high-temperature steam as both the heat source and the gasification agent in an oxygen-starved (air free) environment.. The impact on the environment in terms of air pollution and global climate control is minimized. The advanced technology developed in this project will help ensure the availability of a highly efficient technology to meet the cost-effective biomass to hydrogen mandate for future energy sources.
2	Characterization and Leachability of Coal Combustion Residues in Florida Lena Ma University of Florida Solid waste management and recycling are of major environmental concerns in Florida as well as in the nation. This project addresses an important solid waste in Florida, i.e., coal combustion residues (CCR) detailed in #2-4 of the current Center’s Research Agenda. CCR are the second largest waste streams generated in the US. Over 500 power plants nationwide generate >130 million tons of CCR each year. They are either recycled or disposed in landfills and on-site storage ponds. However, there are some concerns about the potential impacts of trace metals in CCR on the environment and ecosystem. The CCR spill in Kingston promoted USEPA to draft a proposed rule to regulate CCR under RCRA. The objectives of this research are two fold: 1) to collect and characterize CCR produced by major utilities in Florida including basic characterization and total elemental concentrations; and 2) assess the leachability and mobility of Hg and As in CCR when disposed on land or in ash ponds. We will employ EPA methods to assess Hg and As leachability when disposed on land under equilibrium conditions using batch experiments. For Hg and As mobility, we will use column experiments simulating ash slurry stored in ash ponds. Our research should greatly benefit FDEP, the public and utility industries.
3	Onsite Treatment of Leachate Using Energized Processes Daniel E. Meeroff Florida Atlantic University FAU has pioneered the advancement of landfill leachate treatment systems using the photochemical iron-mediated aeration process and the TiO2 photocatalytic process at lab scale in previous research funded by the Hinkley Center. In 2011, the Bill Hinkley Center for Solid and Hazardous Waste Management issued a research grant to FAU Lab.EES to continue to develop advanced oxidation processes for detoxification of landfill leachate. Previous work funded by the Center has led to the development of reactor prototypes for pilot scale testing. These include a plug flow coil reactor and a falling film reactor. The objective of the proposed research is to test the prototype reactors at pilot scale for the removal of COD/BOD, ammonia, heavy metals, color, and pathogens. Another important aspect will be to develop a method to recover the photocatalyst for reuse, prior to safe discharge of the treated leachate. If this process is found is as cost effective as the laboratory bench scale version, a potential for large cost savings in leachate management can be realized.
4	Pump and Treat Aerobic Flushing Bioreacator Landfill-Year2 Debra Reinhart University of Central Florida Conventional landfilling will leave the majority of waste constituents for later release; bioreactor landfilling will leave significantly less, but recalcitrant organics and ammonia remain problematic. The proposed Pump and Treat Aerobic Flushing Bioreactor Landfill (PTAFBL) will reduce the potential for pollutant leaching, dramatically shortening the post-closure care period and reducing the potential for long-term adverse environmental impact. The goal of this proposed research is to define the technological requirements of a PTAFBL as a means of sustainable landfilling of municipal solid waste through laboratory-scale simulation of the process. Results will permit quantification of the economics, pollution reduction potential, and energy consumption of the process in comparison with traditional and bioreactor landfills.
5	Exploring Pathways and Limitations to Recycling Combustion Residues in Florida Timothy Townsend University of Florida This study aims to identify the current limitations to combustion residue reuse in Florida, as well as investigate possible pathways to facilitate the recycling of these materials. The end goal is to outline practical steps needed to foster combustion residue recycling or to evaluate whether such recycling should be a desired practice in Florida’s future. In detail, this research will be conducted to meet the following specific objectives: 1) compile and critically assess the state of science and practice with regard to the recycling of combustion residues, 2)form a working group of experts and foster a dialogue (through face to face meetings) on the current status and future of combustion residue recycling in Florida, 3) collect additional research data to assess fundamental questions regarding the potential for combustion residue based on critical data gaps identified in meeting objective 1 and based on feedback from the working group, and 4) produce a white paper that summarizes the research and the consensus of the working group, including recommendations for practical future steps needed to foster combustion residue recycling or to evaluate whether such recycling should be a desired practice in Florida.
6	Bioremediation of Landfill Leachate and Co-production of Biodiesel-Year 2 Ann Wilkie University of Florida The purpose of this research project is to identify algae that can effectively remediate landfill leachate. The study will characterize native Floridian algae for their tolerance of landfill leachate, effectiveness at remediating the landfill leachate, and the potential use of the algal biomass as a feedstock for biodiesel production. The research conducted under this project will lay the biological foundation for implementing algal bioremediation of landfill leachate in Florida.
7	Slag Quality and Air Emissions From Plasma Arc Gasification of MSW: Bench-Scale Investigation Timothy Townsend University of Florida Plasma technology has been proposed for municipal solid waste (MSW) treatment in several municipalities in Florida. Although a limited number of small-scale projects utilize plasma technology for MSW and other wastes in different parts of the world, this technology has not been used at the large scale being proposed in Florida. This reearch will provide data on the emissions and risks associated with solid and gaseous products of this technology.
8	Diverting Food Waste From Landfills Dr. Ann C. Wilkie University of Florida Food waste represents a significant proportion of Florida’s municipal solid waste. Currently the vast majority of food waste is landfilled, where it can create many problems for solid waste handlers including methane emissions, nutrients and organic matter in leachate, and odor and vermin problems. This project examines the possibilities of diverting this food waste from landfills for anaerobic digestion.
9	Tool for Assessing Potential Iron Exceedances in Groundwater at Landfill Sites Timothy G. Townsend University of Florida Ongoing research and groundwater monitoring data from landfill sites indicate that iron contained in soils and aquifer media can be mobilized as a result of landfill construction and operation, a result of a process known as reductive dissolution. Research is now underway (funding from the Hinkley Center) to develop a tool that can be used to assess the potential for naturally occurring iron to be released into groundwater at landfill sites. The fundamental objective of this proposal is to build upon recent research conducted on iron at Florida landfills to develop an approach for evaluating future landfill sites for their potential to result in elevated iron concentrations in groundwater. This research will combine existing (and new) laboratory data with fate-and-transport modeling output to develop a methodology that would allow an engineer/geologist to predict the extent and degree of iron impact in the groundwater downgradient of a landfill.
10	Siloxanes in MSW: Quantities in Waste Components, Release Mechanisms during Waste Decomposition and Fate in the Environment Berrin Tansel Florida International University Use of siloxanes in consumer products (i.e., fabrics, paper, concrete, wood, adhesive surfaces) have significantly increased in recent years due to their excellent water repelling and antimicrobial characteristics. Air samples collected near landfills show that siloxanes are released to the environment via landfill gas (LFG) and transported with wind currents. Siloxanes contain silicon atoms attached to organics; hence, they are converted to silicates (SiO2 or SiO3) during combustion. Some waste to energy (WTE) facilities have installed gas treatment processes (e.g., carbon adsorption, silica gel adsorption) to reduce deposit formation in engine parts. However, the addition of gas treatment systems increases the energy recovery costs at WTE facilities operated with LFG. Objectives of this research are to evaluate: 1. Current and projected quantities of siloxane containing wastes entering landfills, 2. Release mechanisms of siloxanes from waste components, 3. Fate of siloxanes released to environment from landfills, 4. Human health concerns associated with disposal of siloxanes.
11	Drinking Water Sludge Characterization Study Timothy Townsend University of Florida To characterize drinking water sludge from Florida water treatment facilities for the total and leachable concentrations of inorganic elements of potential concern. This work will expand upon previous work for the Hinkley Center regarding drinking water sludge by (i) examining the characteristics of sludge produced from facilities that include multiple chemicals in the treatment process (e.g., lime softening plus ferric coagulation) and (ii) conducting a more robust set of leaching experiments that will allow better assessment of potential risk posed by disposal in submerged conditions.
12	Sustainable Management of Pollutants Underneath Landfills Daniel Meeroff Florida Atlantic University High concentrations of iron, and perhaps other constituents of concern such as arsenic, have been observed in groundwater and soils around municipal solid waste landfills in Florida and elsewhere. The levels have been attributed to reductive dissolution of the native chemistry in the soil perhaps caused by a shadowing effect of the landfill liner, which inhibits the reaeration of the shallow aquifer beneath a properly lined landfill. In this study, the research team will evaluate the validity of this hypothesis;refine a preliminary list of potential engineering management alternatives for controlling the release of contaminants in-situ, and conduct laboratory experiments on management methods for dealing with this issue. In a previous research grant, “Management of subsurface reductive dissolution underneath landfills,” funded by the Hinkley Center, an innovative groundwater circulation well technology was investigated for control of iron releases.
13	Multi-Objective Agent-based Modeling and Optimization of Single Stream Recycling Programs Nurcin Celik University of Miami In this research, the goal is to develop an agent-based simulation-based decision making and optimization framework for the effective planning of single stream recycling (SSR) programs. The proposed framework will be comprised of two main modules: 1) the simulation module, and 2) the fleet utilities optimization module. The simulation module is where various sources of system uncertainties will be parameterized and incorporated into the simulation model of SSR. Alternatives of SSR with respect to characteristics, cost, environmental impacts, location, materials addressed, types and capacities of the processing facilities needed, government practices, collection frequencies, convenience for public participation factors will also be evaluated at this module. In the fleet utilities optimization module, we will formulate the multicriteria problem of allocation of limited resources. Then, the optimum combination of parameters will be determined via the embedded optimization mechanism for the state of FL to reach its 75% recycling goal. Here, the optimum solution is considered as the combination of parameter which will lead to highest recycling percentage with minimum cost and maximum benefits. Using the proposed tool, the stakeholders will be able to test several “what-if” scenarios in their system before reaching to a conclusion.