Conversion of Paper and Food-rich Municipal Solid Waste Streams to Ethanol through Bioprocessing

Abstract

This article provides a method to convert landfill-designated municipal solid waste (MSW, paper-rich and food-rich) to bioproducts through integrated bioprocessing, also a way of improving the MSW diversion rate to reduce environmental stress. Compositional analysis, bacterial community profiling, homogenization, enzymatic hydrolysis, and yeast fermentation were performed on the collected MSW samples. Results show that these two types of MSW streams are potential feedstock sources for biorefineries based on their abundance, carbohydrate composition, and bioconversion yield. Addition of selected enzyme cocktails to the homogenized substrates resulted in coproduction of C6/C5 sugars and organic acids in the hydrolysates. Maximum 81% glucose and 100% xylose yields were achieved in the paper-rich MSW-derived hydrolysate (PDH). A glucose yield of 96.7% was obtained in the food-rich MSW-derived hydrolysate (FDH). Sugars in PDH and FDH were readily fermentable without detoxification and solid separation. Preliminary fermentation attained 17.7 g/L ethanol from the PDH (69.4% theoretical yield) and 8.9 g/L ethanol from FDH (70.3% theoretical yield), respectively, both comparable with the Avicel-derived hydrolysate (67.6% theoretical yield) used as the control.

Review and Perspectives of Emerging Green Technology for the Sequestration of Carbon Dioxide into Value-Added Products: An Intensifying Development

“…Examples include hydrothermal treatment and torrefaction. However, this process requires a high degree of integration of various process steps and need to be operated under optimal conditions to ensure high yield and quality of the final products …”

“…However, this process requires a high degree of integration of various process steps and need to be operated under optimal conditions to ensure high yield and quality of the final products. 18 The currently suggested strategy for reducing CO 2 concentrations in the atmosphere is implemented with climate change mitigation alternatives such as carbon collection, utilization, and storage systems. 19 Precombustion, postcombustion, and oxyfuel combustion are three different routes used in carbon capture and storage (CCS) technology to reduce CO 2 emissions from power generation and other industrial processes.…”

Thermochemical upcycling of food waste into engineered biochar for energy and environmental applications: A critical review

“…The major upcycling approaches include thermochemical conversions (e.g., hydrothermal carbonization (HTC), pyrolysis, and gasification) and biological conversions (e.g., anaerobic digestion (AD)) [4,5]. AD is extensively investigated for transforming food waste into valueadded products, owing to its considerable advantages of cost-effectiveness, mild operating conditions, and relatively low energy consumption [6][7][8][9]. However, AD generally requires a long residence time and a high-quality feedstock [10].…”