As rates of textile manufacturing and disposal escalate, the ramifications to health and the environment through water pollution, microplastic contaminant concentrations, and greenhouse gas emissions increases. Discarding over 15.4 million tons of textiles each year, the U.S. recycles less than 15%, sending the remainder to landfills and incinerators. Textile reuse is not sufficient to de-escalate the situation; recycling is necessary. Most textile recycling technologies from past decades are expensive, create low quality outputs, or are not industry scalable. For viability, textile recycling system designs must evolve with the rapid pace of a dynamic textile and fashion industry. For any design to be sustainable, it must also be flexible to adapt with technological, user, societal, and environmental condition advances. To this end flexible and sustainable design principles were compared: overlapping principles were combined and missing principles were added to create twelve overarching sustainable, flexible design principles (DfSFlex). The Fiber Shredder was designed and built with flexibility and sustainability as its goal and evaluated on how well it met DfSFlex principles. An evaluation of the Fiber Shredder's performance found that increased speed and processing time increases the generation of the desired output - fibers and yarns, manifesting the principles of Design for Separation in design and Facilitate Resource Recovery in processing. The development of this technology, with the application of sustainable and flexible design, fiber-to-fiber recycling using mechanical systems appears promising for maintaining value while repurposing textiles.
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Low-Pressure Hydrothermal Processing of Disposable Face Masks into Oils
A total of 5.4 million tons of face masks were generated worldwide annually in 2021. Most of these used masks went to landfills or entered the environment, posing serious risks to wildlife, humans, and ecosystems. In this study, batch low-pressure hydrothermal processing (LP-HTP) methods are developed to convert disposable face masks into oils. Three different materials from face masks were studied to find optimal processing conditions for converting full face masks into oil. The oil and gas yields, as well as oil compositions, depend on the feedstock composition, particle size, and reaction conditions. Yields of 82 wt.% oil, 17 wt.% gas, and minimal char (~1 wt.%) were obtained from full masks. LP-HTP methods for converting face masks have higher oil yields than pyrolysis methods in the literature and have lower operating pressures than supercritical water liquefaction. LP-HTP methods for face masks can increase net energy returns by 3.4 times and reduce GHG emissions by 95% compared to incineration. LP-HTP has the potential to divert 5.4 million tons of waste masks annually from landfills and the environment, producing approximately 4.4 million tons of oil.
more » « less- Award ID(s):
- 2112554
- PAR ID:
- 10529174
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Processes
- Volume:
- 11
- Issue:
- 10
- ISSN:
- 2227-9717
- Page Range / eLocation ID:
- 2819
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/pr11102819
