Trash to Treasure: REUSE Creates Feedstock from Plastic Waste
ARPA-E recently released a funding opportunity to develop innovative new technologies that would convert waste into fuel feedstock. Please visit ARPA-E’s funding portal to submit an application, read our white paper for more detailed technical information, or watch a recorded webinar on the topic featuring ARPA-E Program Director Jack Lewnard.
Today, the U.S. is awash in discarded plastic. The Environmental Protection Agency (EPA) estimates that in 2017[1], the country produced 34.8 million metric (MM) tons of municipal solid waste (MSW) plastic. 26.3MM tons of that ended up in domestic landfills. Some countries that previously imported a wide range of U.S. recycled plastic have refused lower-grade materials for the last few years; and prices for some grades of recycled plastics have dropped to zero, making it literally worthless. Like plastic, U.S. paper has also experienced waste import bans. Paper waste exports dropped from 21 MM tons in 2018 to 18 MM tons in 2019, and the amount of paper going to landfills has consequently increased.
Unfortunately, MSW doesn’t just sit inertly in landfills. It has significant embedded energy and is estimated to release significant greenhouse gas (GHG) emissions of 1.4 x 106 metric tons of methane.[2] ARPA-E is therefore looking for technologies that would divert MSW from landfills (to avoid emissions) and instead take advantage of embedded energy and/or value-add products and convert them to a high-energy content liquid product.
Recently, we had an opportunity to sit down with Dr. Jack Lewnard, program director for ARPA‑E REcyle Underutilized Solids to Energy (REUSE) program to discuss the transformation from plastic and paper trash to energy treasure.
In 2013, China began restricting imports and in 2018, completely banned several types of imported waste, including plastics. This action greatly affected recycling industries worldwide. How has this specifically impacted the U.S.?
After China banned almost all waste imports in 2018, many countries, including the U.S., began to divert their plastics to new destinations in Southeast Asia. Then those new destinations began to follow China’s lead. Countries including Malaysia and Vietnam have cut back on plastic and paper imports. As a result, the U.S. needs to take more responsibility for more of our own plastic and paper waste, which now ends up in landfills.
Plastics and paper sent to landfills come from diverse sources, and amount estimates vary. The REUSE program is focusing on materials sent to landfills from industrial facilities and the approximately 300 Material Recycle Facilities (MRFs), which sort “blue bin” recyclables. MRFs are currently sorting and baling a variety of plastic and paper grades, some of which are being landfilled since markets have collapsed.
ARPA-E has been looking at several Waste-to-Energy (WTE) technologies. What are some of other program topics ARPA-E is considering?
In addition to REUSE, ARPA-E is seeking novel ideas and transformational technology in the following areas:
a) Converting Solids Waste to Energy-Intensive Materials seeks technical pathways that can transform waste-to-materials and energy processes into viable options for the U. S. For details from the November 2019 workshop, please see https://arpa-e.energy.gov/events/converting-solid-waste-energy-intensive-materials-workshop.
b) Waste-To-Carbon (WTC) technologies such as enhanced/catalyzed hydrothermal carbonization of unsorted MSW and/or municipal wastewater (MWW, or sewage) to produce carbon/char-like products (This program is in early stages, so stay tuned for updates.)
What does ARPA-E aim to achieve with REUSE?
ARPA-E seeks to support the development of technologies to convert high-energy materials—certain plastics (#1-7 polymers, rubber, and composites) and paper—currently going to landfills into a high-energy content liquid product. In particular, ARPA-E is interested in technologies that would lead to economically viable “liquefaction processes” that create a high-energy content liquid that can be easily shipped to, and stored at, central locations. The liquid product could be used as a fuel blend stock or an intermediate for further conversion to fuels or chemicals. It does not need to be a highly refined fuel such as gasoline or diesel. The ultimate end products could come from up- or down-cycling the feedstocks. (Up-cycling is when the process converts feedstock into new products or better-quality products. Down-cycling is when the process converts feedstock (e.g., plastic) into a product that is of lower quality, functionality, or cost than what was originally used as feed. )
Deployment of multiple low-cost, simple, flexible, small-scale (100-500 ton per day) regional facilities using modular plants is anticipated. This scale is consistent with the sources for high-energy materials, which include the ~300 MRFs and industrial waste sources.
Why are the target high-energy materials limited to the items listed?
The larger objective of REUSE is to prevent plastic and paper from being sent to landfills. ARPA-E does not intend to compete with current recycling businesses. PET (polyethylene terephthalate) and HDPE (high-density polyethylene) bottles are economically attractive to MRFs due to the rising profitable markets resulting from newer recycling technologies. For example, PET can be recycled into new PET containers, carpet, clothing, packaging, automotive parts, etc. And many grades of paper are very attractive for recycling today.
However, the situation for other plastics and mixed paper is not as positive. The market for “#3-7” plastics (PVC, LDPE, PP, and PS, or polyvinyl chloride, low-density polyethylene, polypropylene, and polystyrene, respectively, as well as non-categorized plastics) has effectively collapsed due to bans by waste-importing countries. Recently the price of mixed plastic dropped to zero.[3] Many MRFs do not accept #3-7 plastics, and the low price has led some communities to suspend their collection of them.[4] Similarly the price for mixed paper is now negative.
Considering that recyclers were willing to ship these same materials overseas, is using small-scale regional facilities to recycle the plastics economical?
REUSE is focused on screening technologies that can work at small scale. Plastic and paper wastes are readily available in 100-500 ton/day quantities from MRFs; industrial facilities such as plastic processing plants, autoshredders, and tire recycling facilities; and agricultural sources, which produce about a half-million tons of plastic per year. Regional facilities minimize transportation and storage of waste materials, have smaller environmental footprints than large central plants, and help communities achieve sustainability goals locally, versus sending waste to neighboring communities or other countries. If REUSE technologies can work at a small scale, they will certainly be economical at larger scale, and smaller number of large-scale plants could be built near the largest population centers in the U.S.
Why is the focus of the liquid product fuel blend stock or an intermediate for further conversion to fuels or chemicals versus gasoline or diesel fuel?
Higher-grade end products like gasoline and diesel fuel have stringent fuel standards requiring high stable end product quality assurance. Plastic and paper feedstocks are known to be heterogeneous and varying in terms of the components. Producing products with tight specifications from highly variable feeds at a small facility will require high capital and operating costs. It’s more economical to produce intermediates, and ship these to large downstream facilities that already have the necessary separation and upgrading equipment.
Why is REUSE not encouraging proposals for pyrolysis (decomposition brought about by high temperatures), torrefaction (a mild form of pyrolysis) solvolysis (a chemical reaction in which the solvent is one of the reagents and present in greater excess than required for the reaction), and hydrothermal liquefaction (a process in which hot compressed water is used to convert biomass a liquid biocrude)?
There is extensive research that has been done on pyrolysis, solvolysis, and hydrothermal liquefaction of composites, plastics, cellulosic materials, and mixtures of plastics and cellulosic materials. Additionally, the Department of Energy’s Bioenergy Technology Office (BETO) has invested resources and has active programs for these technologies. As a result, ARPA-E is not encouraging submissions for these processes, unless applicants can demonstrate a disruptive aspect of their technology, and/or a significant techno-economic breakthrough compared with the current state of the art.
If I have a team that can provide either testing or process modeling and techno-economic analysis but not both, is there still an opportunity for me to participate?
ARPA-E is encouraging proposals from teams that have interesting technologies. ARPA-E can assist applicants who need access to process modeling and/or costing tools.
[1] “Waste-to-Energy from Municipal Solid Wastes” Report U.S Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy BETO, August 2019. Powell J.T & Chertow M.R. “Quantity, Components and Value of Waste Materials Landfilled in the United States” Journal of Industrial Ecology 23.2 (2018) 466-479.
[2] Powell J.T & Chertow M.R. “Quantity, Components and Value of Waste Materials Landfilled in the United States” Journal of Industrial Ecology 23.2 (2018) 466-479.
[3] Update on International & Domestic Recycling Markets, J Semrau, MRF Stakeholder meeting Oct 7, 2019
[4] How recycling has changed in all 50 states, WasteDive, Nov 15, 2019