Waste-To-Energy (WTE) technologies offer promising solutions to alleviate environmental problems associated with landfilling of Municipal Solid Wastes (MSW) generated during wastewater treatment processes while promoting resource and energy recovery. However, these technologies are crucially affected by the uneven mixing of combined MSW compositions. Some of the possible problems caused by the use of MSW for these WTE technologies include contaminated products, low product values, pollutant emission during processing, reactor clogging, corrosion, and catalyst poisoning. The objective of this project is to develop a pretreatment process for combined MSW to produce biorefinery chemicals, higher quality syngas or pyrolysis oil, and fewer pollution byproducts. The success of the project could lead to an innovative green WTE technology that can convert non-recyclable MSW to a domestic source for energy and valuable chemicals, thus, benefiting society by reducing the pressure of MSW landfills. Producing biorefinery chemicals, in addition to high-quality syngas or pyrolysis oil from abundant MSW, can provide an opportunity to lower the feedstock cost in biorefining and improve the economic sustainability of biorefineries while reducing the Nation's dependency on fossil fuels.
Co-mingled MSW can consist of nearly 60% cellulosic wastes, making these wastes a potential source of low-cost biorefinery chemicals. This research proposes a two-step conversion to recover the economic value from the polysaccharides in these wastes as well as to produce better quality syngas or pyrolysis oil products from these wastes. The proposed approach to properly integrate polar-aprotic solvolysis pretreatment of co-mingled MSW with subsequent thermal conversion by gasification or pyrolysis will transform the detrimental characteristics of MSW materials into assets that increase product values and reduce pollutant emissions. Specifically, the proposed approach will utilize the contaminant acids as catalysts and the feedstock moisture as a co-solvent to produce biorefinery chemicals in addition to cleaner and higher BTU syngas or pyrolysis oil. The environmental and economic benefits of the proposed approach will be further enhanced by the use of recyclable biobased green-solvents. The main focus of the proposed research is to gain new insights into the interdependency among the solvent pretreatment, the selectivity of biorefinery chemicals, the quality of syngas/pyrolysis oil, and contaminant formation and transport on MSW conversion. The research outcomes will provide important fundamental mechanisms and insights pertinent to the required reactions, product transport, and product recovery during the polar-aprotic solvent-based conversion of co-mingled organic and synthetic waste materials. The knowledge obtained during this research will lay a strong foundation for the development of a novel WTE strategy for non-recycled co-mingled MSW to achieve high-quality products while reducing pollutants.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
