The Board of Directors of the Environmental Research and Education Foundation (EREF) is pleased to announce the award of three research grants for solid waste research, which were awarded from submissions made to the foundation in January 2015 after a robust vetting process. EREF is the only private, grant making institution with a national and international scope whose sole mission is to support solid waste research and education initiatives. EREF’s research grants program is led by its Research Council, a body of volunteers consisting of technical experts in industry, academia and consulting. The work of the Council is guided by a long range strategic plan with the goal to achieve greater sustainability, good environmental stewardship, higher process efficiency and increased knowledge. Council recommended projects are then reviewed by EREF’s Board of Director’s Projects Committee for a final review and funding allocation.
Design of Waste Transfer Station Concrete Overlays against Premature Deterioration
Investigator: Mohammad Pour-Ghaz, North Carolina State University
Start Date: September 2015
Award Amount: $160,000
The premature deterioration of concrete overlays in waste transfer stations is a major concern for the owners and operators of these facilities. Overlay replacement in these facilities has significant economic impacts including direct costs, operational delays, and planning hurdles. While the overlay deterioration is mainly attributed to the abrasion caused by scraping solid waste, anecdotal evidence suggests that other factors might equally contribute to the deterioration of the overlays. Some of these factors may include contact with acidic leachate from fresh waste, the type and operation of equipment used for handling waste, the amount of waste handled, and the lack of systematic structural design that accounts for concrete material deterioration. If the main contributing factors to deterioration are identified, these overlays can be designed against deterioration, resulting in better long-term performance and predictability, and consequently, reduced life cycle cost for owners and operators. The main objectives of this research are therefore (i) to identify the contributing factors to the premature deterioration of concrete overlays in transfer stations, and (ii) to establish a structural design methodology for the concrete overlay based on the observed degradation mechanism and operational conditions.
Geopolymer-Based Solutions for Coal Combustion Product Solidification and Stabilization
Investigators: Maria Juenger & Lynn Katz, University of Texas at Austin and Gaurav Sant, University of California, Los Angeles
Start Date: September 2015
Award Amount: $285,000
Coal burning power plants produced about 115 million tons of CCPs in 2013 in the US, less than 50% of which found beneficial reuse (http://www.acaa-usa.org). Much of the landfilled or ponded material contains trace elements that are highly soluble and present groundwater contamination concerns. Stabilizing waste residues using CCPs from the power plants themselves to make geopolymers. The objective of the research is to design and evaluate geopolymer mixtures made with coal combustion products (CCPs) to solidify/stabilize flue gas desulfurization (FGD) residues, water treatment residues (WTRs) and other wastes, particularly those that cannot be beneficially used and which present environmental hazards. Geopolymers are solid materials made by reacting aluminosiliceous powders with caustic solutions; these present a potentially more stable alternative to solidification/stabilization (S/S) of CCPs with commercially-produced portland cement and can be made almost entirely with wastes produced by power plants themselves.
Methane Oxidation: Field-Scale Test Sections Experiment
Investigators: Tarek Abichou & Jeff Chanton, Florida State University
Start Date: August 2015
Award Amount: $70,000
The newly published EPA rules provide an option for site-specific methane oxidation values other the default value of ten (10) percent and can range from 0% to 35% depending on the methane flux and the cover type. Such a flux reflects the conditions at the landfill and the thickness of soil cover over majority of the landfill. However, there are 3 key challenges in these new rules that might make it difficult to actually use the higher methane oxidation values in the range that EPA has provided:
- The new rule requires that a ZERO oxidation value is to be used for landfills that have a geomembrane (synthetic) cover with less than 12 inches of cover soil for the majority of the landfill area containing waste.
- A 10% oxidation value is assigned for landfills that do not have a geomembrane with a 12 inches of cover soils, and do not have a soil cover of at least 24 inches for a majority of the landfill area containing waste.
- Higher oxidation values of 35% can only be used for landfills that have a soil cover of at least 24 inches for a majority of the landfill area containing waste and for which the methane flux rate is less than 10 and grams per square meter per day (g/m2/d), and the higher value of 25% can only be used for landfills that have a soil cover of at least 24 inches for a majority of the landfill area containing waste and for which the methane flux rate is between 10 and 70 grams per square meter per day (g/m2/d).
However, the actual effect of the conditions noted in the EPA rules have not been fully explored. The primary objective of this study to measure methane oxidation under different cover conditions and calibrate a methane oxidation model already developed by the research team. The collected data will also provide additional information on methane oxidation in 6” to 18” soil covers under different or varying methane loading. It will also provide data to quantify the additional methane oxidation by a 12” thick compost biocover placed on a 6” daily cover. The proposed field study will evaluate methane oxidation capacities on three previously constructed test sections. The three test sections represent a unique opportunity where LFG is being introduced into soil profiles at a controlled rate. The methane loading to the test sections will be controlled to match the recently published EPA rule on methane oxidation as follows:
- Below 10 g/m2/day
- 10 to 70 g/m2/day
- Above 70 g/m2/day
The results from this research will allow for a comparative analysis of the new EPA requirements with actual field data.
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