This Exploratory Topic works to advance the improvement of the physical or chemical properties of Municipal Solid Waste Incineration (MWSI) ash into valuable products. Teams will explore real-time, cost-effective characterization techniques for the MSWI ash output stream, the feasibility of adding co-feeds to waste pre-combustion, or to the MSWI ash post-combustion to yield a consistent product independent of Municipal Solid Waste (MSW) composition variability, and cost-competitive technologies for the upcycling of MSWI ash fractions into novel valorized products.
The U.S. Environmental Protection Agency estimates that more than a half of MSW generated every year in the U.S. is sent to landfills with the remainder being diverted to recycling, composting, and waste to energy (WTE) processes. Additionally, while the U.S. recycling rate is estimated to be close to 25% of MSW produced, recycling has limitations as a waste disposal process resulting from consumer compliance and confusion, contamination of materials, challenges within recycling markets, and cost-effectiveness generally. These complications can often lead to the problem of “wishcycling” where sorted and processed recyclable materials end up being landfilled or combusted as opposed to actually being recycled. Teams in this Exploratory Topic will address these issues and the challenges associated with recycling and landfilling, focusing on the possibility of generating a significant amount of energy via WTE, and the potential for reducing embodied energy in commonly used materials via the use of end-products.
Projects Funded Within This Exploratory Topic
WASTE-TO-ENERGY (WTE)-DERIVED LOW-CARBON-FOOTPRINT CONCRETE (LCFC)
Rutgers University (RU) aims to produce concrete from incinerator ash and concrete rubble (CR). RU will use its proprietary low-cost technology to create a low carbon footprint concrete. Assuming only electricity for crushing and milling, CR contributes a 5% carbon footprint to an adaptive cement that can be cured one of two different ways. Curing with CO2 will create a -5% carbon-negative carbonate-cement-concrete. Curing with water will create a +6% carbon footprint hydraulic concrete. Both sustainable technologies exact a reduction of 90+% for CO2 emissions and 100% for fossil fuel use. This program will bring cement production capability to states lacking cement mills, reducing CO2 emissions and freeing landfills of CR and WTE-ash.
CITY UNIVERSITY OF NEW YORK: CITY COLLEGE
GYPSUM & CLAY-BASED ADDITIVES TO MSW FOR PRE-COMBUSTION ENHANCEMENT OF SYNGAS AND SOLID RESIDUE IMPROVEMENT
Currently spent fluid catalytic cracking catalysts are classified as non-hazardous. The quantity is significant at nearly 400,000 tons produced annually, which are sent to landfills. Gypsum waste is estimated at 13 million tons annually with only 2% recycled into new wallboard. If these materials can be profitably combined with the nearly 30 million tons of municipal solid waste (MSW) annually processed in waste-to-energy (WTE) facilities, it will increase the MSW going to thermal processing facilities and recover materials currently being landfilled. City College proposes to study the impacts of the chosen co-feeds with MSW on syngas and residual properties. The result will be the production of value-added materials.
GLASS WRX SC
INDUSTRIAL-SCALE UPCYCLING OF MUNICIPAL SOLID WASTE INCINERATOR ASH INTO ENGINEERED CELLULAR MAGMATICS
Glass WRX SC’s technology transforms post-consumer waste glass stored in landfills into porous ceramics called engineered cellular magmatics used in a wide variety of applications. By incorporating municipal solid waste incinerator (MSWI) ash into their existing and new processes, they will introduce industrial-scale upcycling into MSWI operations. MSWI will become “beyond zero waste,” eliminating landfilling ash byproducts of the incineration process and landfill space currently taken up by unrecycled glass at the same time. Glass WRX SC estimates the incorporation of MSWI ash into its existing synthesis techniques could generate an average of $10M+ in revenue per year per incinerator.
UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
RAPID AI-BASED DISSECTION OF ASHES USING RAMAN AND XRF SPECTROSCOPY (RADAR-X)
Municipal solid waste (MSW) management involves three primary practices: landfilling, recycling, and incineration for energy recovery (waste-to-energy or WTE). WTE is a potentially sustainable method of MSW management because it reduces landfilling and generates energy. Incineration reduces input waste mass by 70%. The remaining 30%—in the form of bottom and fly ashes—has to be discarded or landfilled. A main barrier to beneficial use of these ashes is the variability in their composition, which renders them as an unreliable byproduct. The University of Illinois aims to design a low-cost and rapid real-time AI-based ash analysis technology that accurately predicts ash composition and its performance as a potential byproduct.
DESIGNS BY NATURAL PROCESSES
MAKING CEMENT AT AMBIENT TEMPERATURE USING 55% MUNICIPAL SOLID WASTE ASH
Designs by Natural Processes, Inc., aims to make novel cement at ambient temperature using 55% municipal solid waste (MSW) incinerator ash. The team will add low-cost chemicals to better sequester environmentally problematic combustion gases, chemicals, and heavy metals during incineration, eliminating undesired chemicals in the ash-rich cement leachate. The team's objective is to develop an alternative to traditional ordinary Portland cement (OPC), which cannot sequester nearly as much ash (16%). OPC requires a temperature of 1300°C for its manufacture, and sets up in about a month for a compressive strength of approximately 3000 psi. In contrast, the novel cement uses more ash, is chemically based, uses no heat, gives off no CO2, hardens quickly, and averages high strength.