Source: VIRGINIA POLYTECHNIC INSTITUTE submitted to
PILOT DEMONSTRATION OF A MODULAR BIOPROCESS SYSTEM FOR MANUFACTURING CONSUMER BIOPLASTIC PRODUCTS FROM FOOD WASTES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
ACTIVE
Funding Source
OTHER GRANTS
Reporting Frequency
Annual
Accession No.
1029716
Grant No.
2023-79000-38973
Cumulative Award Amt.
$2,400,874.00
Proposal No.
2022-09359
Multistate No.
(N/A)
Project Start Date
Jan 1, 2023
Project End Date
Dec 31, 2025
Grant Year
2023
Program Code
[BPP]- Bioproduct Pilot Program
Recipient Organization
VIRGINIA POLYTECHNIC INSTITUTE
(N/A)
BLACKSBURG,VA 24061
Performing Department
(N/A)
Non Technical Summary
Most commercial plastics used nowadays are petroleum-based. More than 67% of end-of-life plastics end up in landfills while another eight million tons annually make their way into the ocean where they are not degradable and only accumulate. In the past three pandemic years, the global consumption of the single-use plastics for keeping hygiene have created significant societal and environmental concerns. There is an urgent need for developing biodegradable plastics from renewable sources. The use of plastics is closely linked to another important environmental issue, namely food waste. Nearly 40% of food produced is dumped in landfills, accounting for the single largest component of U.S. municipal solid waste, resulting in not only greenhouse gas emissions but also an annual cost of $165 billion in economic loss including the food itself and associated water, energy, and chemicals spent in the food supply chain. The conversion of food waste to "value-added bioplastic materials" that can be biodegraded in environment may offer a unique solution to both environmental issues.This proposed pilot study targets the production of naturally occurring biodegradable polyesters synthesized by many microbes as the basic materials for producing bioplastics capable of being degraded in various environmental conditions including in the ocean. A three-pronged modular bioprocessing system will be experimented in this study to enable a variety of microbial cultures to convert a wide spectrum of food wastes into bioplastics with productivity high enough to outcompete other bioplastic production technologies. The overall goal of this project is to develop and demonstrate a pilot-scale modular bioprocessing system to produce bioplastics from food wastewith cost competency. This will be the first effort to create a modular bioplastic fermentation system tailored for accommodating the food waste with high property variability. The outcome of this three-year project will be a process that delivers marketable bioplastic products made from food wastes. This circular diversion of food waste for bio-based plastic production holds promise to reduce landfill quantity and waste management cost, offset petroleum-based plastic production and pollution, minimize greenhouse gas emission, and bring environmental justice to disadvantaged communities. This pilot study will be performed in a modular system at the 100 literscale with each component individually optimizable to provide outputs contributing to the best overall economic and environmental results. An interdisciplinary team is assembled from three land-grant universities and a private enterprise to provide all the technological and marketing components required for the success of this advanced modular system. An industrial advisory board consisting of stakeholders and beneficiaries of the technology will also be formed to ensure delivery of the technology with good application relevance.
Animal Health Component
80%
Research Effort Categories
Basic
10%
Applied
80%
Developmental
10%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
40353702020100%
Knowledge Area
403 - Waste Disposal, Recycling, and Reuse;

Subject Of Investigation
5370 - Sewage and waste disposal facilities and systems;

Field Of Science
2020 - Engineering;
Goals / Objectives
The overall goal of this project is to develop and demonstrate a pilot-scale modular bioprocessing system to produce bioplastics from food wastes with cost competency. The supporting objectives and plans to accomplish this project goal include: (1) Food waste inventory check and characterization; (2) Modular design of the pilot scale system; (3) Pilot-scale demonstration of VFA production; (4) Pilot-scale PHA fermentation; (5) PHA extraction and purification; (6) Biomanufacturing and characterization of PHA-derived plastics; and (7) Iterative TEA and LCA to improve and judge the success of this project.
Project Methods
This project will pilot test the food waste-to-bioplastic converstion technology using a modular system at the 100 L scale with each component individually optimizable to provide output contributing to the best overall TEA and LCA results. The project team envisions a sustainable bioplastic production process that combines innovative technologies (arrested anaerobic digestion, thermal hydrolysis pretreatment, as well as lipophilic, consortia, and halophilic PHA fermentation), with cell debris recovery and reuse to create high PHA productivity from different types of food wastes, as well as thefeedback from TEA/LCA models incorporated into each step of the production process to steer the project towards success. To this end, this project will enhance food waste hydrolysis, produce PHAs from VFAs and small chain carbons in hydrolysate using the most economical processing methods, and purify the PHAs using an innovative approach for cell lysis and product recovery. This project will address PHA production limitations by using a novel three-pronged approach with innovations in pretreatment of food waste for high yield PHA production without culture contamination, reducing solvent and sterilization costs as well as the end-of-life impacts and costs of both food waste and plastic pollution management.In particular, the success of the feedstock characterization and preprocessing effort will be evaluated by the comprehensiveness and accuracy of the food waste inventory database to be enriched throughout this project duration, which will be double confirmed by the lab characterization data. The success of the pilot system modular design effort will be evaluated by the punctual delivery of the system setup and installation. The success of the pilot-scale food waste hydrolysis effortwill be measured by the hydrolysis efficiency and the corresponding TEA/LCA results. The success of the pilot-scale PHA fermentation effort will be measured by the cellular PHA contents obtained from the fermentation. The success of the PHA extraction and purification effort will be evaluated by PHA recovery efficiency and PHA purity. The success of thebioplastic product biomanufacturing effort will be evaluated by the quality of both flexible and rigid bioplastic packaging articles such as prototypes of films and containers to be produced from this project. Last but not the least, the overall success of the project will be evaluated by a complete estimation of the bioplastic minimum product-selling price (MPSP) and their global warming potential from food waste under various process parameter combination to be verified in the pilot study.

Progress 01/01/24 to 12/31/24

Outputs
Target Audience:With our efforts of disseminating research outcomes through publication, media outlets, patent filing, attending professional conference and workshops, hosting lab and facility tours, as well as project meetings, we were able to reach out to public audiences such as 1) Waste management professionals who will be benefited from the cost and environmental assessmewannt findings; 2) Food processors who will be benefited from the downstream cell lysis and product recovery techniques developed from this project and also the opportunity to get value-added processing of their food waste to bioplastics; 3) Bioplastic packaging converters and consumers who will be benefited from the products made from the outcomes of this project; 4) general publics who are interested in renewable plastics; 5) news media who are keen on biopalstics production from food waste; 6) Professionals who are working in the field of bioplastic synthesis and food waste valorization, fermentation engineering, biodegradable biopolymer, biodegradable plastics, circular bioeconomy, etc. 7) The consumer packaged goods (CPG) industrial professionals who look for renewable packaging solutions Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?In total, 5 PhD students, 1 MS student, 1 postdoctoral fellow, and 1 undergraduate students have been trained for dark fermentation, PHA production, purification, and extraction, FOG bioconversion, chemical composition analysis, and microbiological techniques for conducting fermentation experiments, biomanufacturing, and LCA/TEA. Moreover, all graduate students have also been trained for writing scientific articles through one-on-one meeting with their respective PDs. In addition, the graduate students were trained in effective communication via oral and poster presentations in professional conferences. How have the results been disseminated to communities of interest?The team has disseminated research results to communities of interest through conference oral and poster presentations,media reports, book chapters,and technical papers publications. Moreover, we also reached out to potential industrial users of the technology and recieve very positive feedback. Two industrial users, namely Dongsung Chemical and CJ Bio, are negociating with VT for obtaining licenses to use our technology. What do you plan to do during the next reporting period to accomplish the goals?Objective 1: Food waste inventory check and characterization More different types of food waste will be collected and characterized for the pilot scale testing. Objective 2: Modular design of the pilot scale system Based on the pilot scale testing results, we may further modify the modular design to enhance the PHA yield and titer. Objective 3: Pilot-scale demonstration of VFA production The dark fermentation conditions will be further tailored towards more C3/C5 VFA production to increase the HV content in the PHBV produced from Haloferax mediterraneifor better TEA results because soft bioplastic made by higher HV content has much higher market value. The VFA yield will also be further increased by mitigating the product inhibition and the corresponding organic loading increase. Objective 4: Pilot-scale PHA fermentation To reduce the production cost for salt usage and salty discharge treatment, both high salinity food waste and salty fermentation broth recycle approaches will be explored in the next step of Haloferax mediterraneifermentation optimization. To further increase the PHA titer, both fed batch cultivation strategy and membrane bioreactor will be researched. To mitigate inhibitors that either came from the dark fermentation or produced during PHA fermentation, a series of inhibitior identification and removalmethods will be developed. Objective 5: PHA extraction and purification The HPH-based PHA extraction and purification process will be optimized to improve medium-chain PHA recovery rate and PHA purity The tangential flow membrane filtration process will be used to further purity the PHA extracted using the HPH methods. Objective 6: Biomanufacturing and characterization of PHA-derived plastics Prototypes of flexible packaging system with both types of short chain and long chain PHAsproduced in this project will be explored for packaging application while improving their physico-chemical properties with a series of biopolymeric ingredients. Multiple combinations with other bioplastics will be tested for understanding the properties and functionalities in terms of packaging systems. Objective 7: Iterative TEA and LCA to improve and judge the success of this project The assessment and sensitivity analysis will be completed. The team will also begin evaluating specific scenarios for the biorefinery deployment in the U.S. locations and evaluate supply chain configurations.

Impacts
What was accomplished under these goals? Objective 1: Food waste inventory check and characterization Food wastes samples were collected from food processing companies, biodiesel facilities, and local restaurants. Food waste characterization, including TS, VS, pH, COD, total nitrogen, ammonia nitrogen, phosphorus, and minerals, were analyzed following standard methods. All the samples were prepared, shipped, and measured following the protocols. Particle size distribution of the food waste before and after wet grinding was also measured. Objective 2: Modular design of the pilot scale system QEG has designed and delivered the modular pilot-scale bioprocessing system based on the inputs from the PD and Co-PDs. The modular design at the pilot scale includes both new and existing bioreactors and tanks from QEG, VT, and UM. The UM 130-liter fermenter has been refurbished and delivered to the VT pilot facility. A 50-liter and a 100-liter glass fermenters were purchased by Quasar for the fermentation using halophilic strains (e.g., Haloferax Mediterranei) to accomondate the high salinity substrates. The two bioreactors have been delivered to VT and has been used for pilot scale testing. VT has purchased a 100-L anaerobic digesterfor dark fermentation, a disc centrifuge for PHA recovery, a high-pressure homogenizer for PHA extraction, and a trangential flow filtration system for PHA purification. We have also compared the separation efficiency between disc centrifuge and rangential flow filtration system in terms of PHA recovery, energy consumption, and solids residues in the permeate. We have collected performance data for each individual module including mass balance and product yields and recoevery at eachstage which was used to finalize our modulardesign for demonstrating PHA productiton from food waste. Objective 3: Pilot-scale demonstration of VFA production VT team has continuously operated the 100 L pilot-scale anaerobic digester in the dark fermentation mode for more than 300 days with food waste as feedstock to produce sufficient VFA broth for subsequent PHA fermentation by Haloferax mediterranei. The loading rate and pH levels have been optimized for maximizing the VFA production. Pilot-scalemicrobial electrolysis cell has also been incorporated into the 100 L digester for further enhancing VFA yield and C3, C5 VFA fractions.Meanwhile, a 30 L anaerobic digester has been operated in the dark fermentation mode for 15 months toprovide seed sludge for the pilot-scale anaerobic digesters. VFA production with high yield has been achieved in the 100 L anaerobic digester. The seperation efficienciesand the harvested VFA composition have been analyzed and used for PHA fermentation as well as TEA and LCA. Objective 4: Pilot-scale PHA fermentation The 130 L fermentor was refurbished and commissioned for the pilot scale testing. A 10 L eppendorf fermenter was operated to provide seed culture. Large quantity of medium chain PHA has been produced from this130 L fermentor with either raw FOG or food waste digestate as feedstock.Meanwhile, more than 10 rounds of50 L PHA fermentation has been accomplished by using Haloferax mediterraneito produce PHBV from high salinity biodesiel wastewater, food waste processing wastewater, and food waste digestate. Very high productivity of PHBV has been produced for downstream processing. Objective 5: PHA extraction and purification A new pilot-scale disc-stack centrifuge was implemented to separate bacterial cells from fermentation broth. A high pressure homogenization (HPH)-based downstream process was employed to break the bacterial cell walls for extracting PHA from the fermentation broth. This method avoids the heavy use of environmentally toxic chemicals and potentially reduces the carbon footprint and the cost of PHA extraction and purification. The HPH-based downstream processing achieved a PHBV recovery efficiency of 85% and a purity of 90%. The extracted PHBV was further purified by ethanol washing to achieve 94% purity. The extracted PHA was thoroughly characterized, and the results showed that HPH extraction did not alter the thermal properties of PHBV, increasing HPH pressure led to a slight reduction in molecular weight. Objective 6: Biomanufacturing and characterization of PHA-derived plastics The potential of using the medium chain PHA produced from food waste as sticky label systems has drawn great attention from packaging industry. Therefore, this researchhas been successfully initiated by Dr. Kim' lab using the medium chain PHA extracted from Objective 5. The further detail process including application study is under exploration. Furthermore, thriple layer, composed of paper, biopolymer, and PHA, has been successfully developed by a novel spray coating procedure. This new approach is in the middle of patent-filing process at Viriginia Tech. Currently, Virginia Tech is in communication with an industrial partner, Dongsung Chemical (a bioplastic converter and manufacturer), to commercialize not only PHAs produced from food wastes but also the novel spray coating biomanufacturing process for application in packaging. Objective 7: Iterative TEA and LCA to improve and judge the success of this project The baseline TEAof the modular bioprocessing system for PHA production from three types of food wastedemonstrated promising economic and environmental outcomes. The study estimates a fixed capital investment of $110 million and an annual operating cost of $105 million. The minimum selling price (MSP) of PHA is estimated to be $3.13/kg, suggesting it could compete within the bioplastics market. LCA highlights environmental benefits, with a global warming potential (GWP) of -3.19 kg CO-eq/kg PHA, emphasizing the advantages of utilizing diverse waste streams and reducing reliance on conventional disposal methods. Other environmental impact assessments further demonstrated sustainability advantages such as acidification potential (AP), eutrophication potential (EP), and photochemical oxidation (PO),indicatingreduced environmental burden. Sensitivity analysis identifies key cost factors, including feedstock price, chemical use, and PHA yield are the most critical parameters affecting MSP. Further optimization efforts, such as improved solvent recovery and in-house microbial culture production, could enhance process efficiency and economic viability. This study underscores the potential of integrating multiple waste streams into a scalable and sustainable PHA production model.

Publications

  • Type: Peer Reviewed Journal Articles Status: Published Year Published: 2024 Citation: Zhang X.Y., An Z.H., Wang J.F., Lansing S., Amradi N.K., Haque M.S., Wang Z.W. (2024) Long-term effects of cycle time and volume exchange ratio on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) production from food waste digestate by Haloferax mediterranei cultivated in sequencing batch reactors for 450 days. Bioresource Technology, 416, 131771
  • Type: Peer Reviewed Journal Articles Status: Published Year Published: 2024 Citation: Zhang X.Y., Wang J.F., Zhang Y.X., Qing W.H., Lansing S., Shi J., Zhang W., Wang Z.W. (2024) Anhydrous volatile fatty acid extraction through omniphobic membranes by hydrophobic deep eutectic solvents: mechanistic understanding and future perspective. Water Research, 257, 15, 121654
  • Type: Peer Reviewed Journal Articles Status: Published Year Published: 2024 Citation: Zhao, F., Wang, Z., and Huang, H. (2024). Physical Cell Disruption Technologies for Intracellular Compound Extraction from Microorganisms. Processes, 12(10), 2059
  • Type: Other Journal Articles Status: Submitted Year Published: 2024 Citation: Zhao, F., Haque,, M.D., Zhang, X., Wang, Z., Y. Kim, Huang, H (2025). Pilot-scale Production of Polyhydroxyalkanoates from Glycerol Waste by Haloferax mediterranei
  • Type: Other Journal Articles Status: Submitted Year Published: 2025 Citation: Cao, C., Kim, YT., Ahn, KY., Hong,SJ (2025). A novel paper coating process with bioplastic compostes fabricated with PLA and PHA
  • Type: Other Journal Articles Status: Under Review Year Published: 2025 Citation: Khatun, S., Ganguly, A. Wang, Z., Mba Wright, M. (2025) Life Cycle Cost and Emissions Analysis of a Modular Bioprocess System for Producing Polyhydroxyalkanoates from Food Waste via Heterogeneous Fermentation. Journal of Cleaner Production
  • Type: Book Chapters Status: Accepted Year Published: 2025 Citation: 1. Chatper 2: Advancements, Applications, and Challenges of Polyhydroxyalkanoates (PHAs) in Packaging as Biodegradable Bioplastics KY Ahn, C.Tayor, YT Kim, in AIBE 10: Sustainable bioplastics production from renewable sources., Edited by Yebo Li. Elsevier
  • Type: Book Chapters Status: Accepted Year Published: 2025 Citation: 2. Chapter 4:Techno-economic and life cycle analysis of PHA production from organic waste. Khatun S., Mba Wright M. in AIBE 10: Sustainable bioplastics production from renewable sources. Edited by Yebo Li. Elsevier
  • Type: Book Chapters Status: Accepted Year Published: 2025 Citation: Zhang X.Y., Zhao F., Wang M., Huang H., Kim Y.T., Lansing S., Wang Z.W. (2025) Haloferax mediterranei for Bioplastics Production from Wasted Materials: Potential, Opportunities, and Challenges. In: Advances in Bioenergy, volume 10, Elsevier Inc., Cambridge, MA.
  • Type: Book Chapters Status: Accepted Year Published: 2024 Citation: 3. Mohandessi, M., Bandara, K., Wan, C.* 2024. Green technologies for recovery of polyhydroxyalkanoates: Opportunities and perspectives. Advances in Bioenergy, Volume 10, in press. Edited by Li, Y., Elsevier, USA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2024 Citation: Zhang X.Y., Hassanein A., Amradi N., Lansing S., Wang Z.W. (2024) Strategy for Haloferax Mediterranei-based PHA production from food waste. 2024 ASABE Annual International Meeting. July 28  31, Anaheim, CA, USA
  • Type: Book Chapters Status: Accepted Year Published: 2024 Citation: Khatun S., Ganguly A., Wang Z., Mba Wright M. Techno-Economic Analysis of a Modular Bioprocess System for Producing Polyhydroxyalkanoates (PHAs) from Food Waste Via Heterogeneous Fermentation. October 28, 2024, San Diego, CA, USA.
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2024 Citation: Yisheng Sun, Yafu Zhong, Caixia Wan. Pilot-scale mcl-PHA production from food wastes. Oral presentation. Denver, Colorado, August 17-22, 2024
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2024 Citation: Caixia Wan. Advancing Circular Bioeconomy through Sustainable Biorefinery Systems. Invited talk, 14th International Conference on Environmental and Public Health Issues in Asian Mega-cities (EPAM 2024), November 13-15, 2024, Univ. of Seoul, Seoul, South Korea
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2024 Citation: 1. Zhang X.Y., Amradi N., Hassanein A., McCoy E.L., Lansing S., Yates M.D., Wang Z.W. (2024), Enhancement of 3-Hydroxyvalerate fraction in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) produced by Haloferax mediterranei fed with food waste digestate as a substrate. WaterJAM 2024, September 9-12, Virginia Beach, VA
  • Type: Book Chapters Status: Accepted Year Published: 2024 Citation: 2. Zhang X.Y., Hassanein A., Amradi N., Lansing S., Wang Z.W. (2024) Long-term stability of continuous PHA production from food waste by Haloferax mediterranei. 2024 ASABE Annual International Meeting. July 28  31, Anaheim, CA, USA
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2024 Citation: F. Zhao, M.D. Haque, Z. Wang, H. Huang. Recovery of polyhydroxyalkanoates from Haloferax mediterranei utilizing glycerol waste. ACS Fall 2024 National Meeting & Expo., Denver, CO, August 2024.
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2024 Citation: Yisheng Sun, Yafu Zhong, Caixia Wan. Pilot-scale mcl-PHA production from food wastes. Sci-Mix Poster. Denver, Colorado, August 17-22, 2024.
  • Type: Websites Status: Published Year Published: 2024 Citation: National Geographic Article: Swartz, A. (2024, July 23). Biodegradable plastic existsbut its not cheap. National Geographic. Retrieved from https://www.nationalgeographic.com/science/article/bioplastic-biodegradable-compostable-plastic-pha
  • Type: Websites Status: Published Year Published: 2024 Citation: Virginia Tech News Article: Esterhuizen, M. (2024, June 5). Virginia Tech researchers work to create biodegradable bioplastics from food waste. Virginia Tech News. Retrieved from https://news.vt.edu/articles/2024/06/cals-bioplastics.html
  • Type: Websites Status: Published Year Published: 2024 Citation: ASABE Blog Post: Hill, S. (2024, March 5). Advancing circularity with bioplastics. Retrieved from https://www.asabe.org/AboutUs/News/ASABE-Blog/Advancing-Circularity-with-Bioplastics
  • Type: Websites Status: Published Year Published: 2024 Citation: Earth.com News Article: Putol, R. (2024, July 11). Transforming food waste into biodegradable bioplastics. Earth.com. Retrieved from https://www.earth.com/news/transforming-food-waste-compost-into-biodegradable-bioplastics/
  • Type: Websites Status: Published Year Published: 2024 Citation: SCI Chemistry and Industry Article: Reade, L. (2024). Trash to treasure: Innovative uses for food waste. Chemistry & Industry, (7-8). Retrieved from https://www.soci.org/chemistry-and-industry/cni-data/2024/7-8/trash-to-treasure-innovative-uses-for-food-waste
  • Type: Websites Status: Published Year Published: 2024 Citation: EurekAlert! Image: Virginia Tech. (2024). Fujunzhu Zhao, a Ph.D. student, works in Zhiwu "Drew" Wang's lab. EurekAlert!. Retrieved from https://www.eurekalert.org/multimedia/1033611


Progress 01/01/23 to 12/31/23

Outputs
Target Audience:With our efforts of disseminating research outcomes through publication and media outlets, attending professional conference and workshops, hosting lab and facility tours, as well as project meetings, we were able to reach out to public audiences such as 1) Waste management professionals who will be benefited from the cost and environmental assessment findings; 2) Food processors who will be benefited from the downstream cell lysis and product recovery techniques developed from this project and also the opportunity to get value-added processing of their food waste to biopaltics; 3) Bioplastic packaging converters and consumers who will be benefited from the products made from the outcomes of this project; 4) general publics who are interested in nenewable plastics; 5) news media who are keen on biopalstics production from food waste; 6) Professionals who are working in the field of bioplastic synthesis and food waste valorization, fermentation engineering, biodegradable biopolymer, biodegradable plastics, circular bioeconomy, etc. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?In total, 3 PhD students, 1 MS student, 1 postdoctoral fellow, and 7 undergraduate students have been trained for dark fermentation, PHA production and extraction, FOG bioconversion, chemical composition analysis, and microbiological techniques for conducting fermentation experiments, biomanufacturing, and LCA/TEA. Moreover, all graduate students have also been trained for writing scientific articles through one-on-one meeting with their respective PDs. How have the results been disseminated to communities of interest?The team will disseminate research results to communities of interest through conference oral and poster presentations, media reports, book chapters, factsheets, and technical papers publications. What do you plan to do during the next reporting period to accomplish the goals?Objective 1: Food waste inventory check and characterization More food waste will be collected and characterized for the pilot scale testing. Objective 2: Modular design of the pilot scale system Based on the pilot scale testing results, we will modifier the modular design which can be used for the design of future commercial scale systems. Objective 3: Pilot-scale demonstration of VFA production 100 L anaerobic digester will be operated in dark fermentation mode to mass produce VFA from food waste after process optimization and troubleshooting. The produced VFAs will be used as feedstock in 130 L fermenter for pilot-scale PHA production. Objective 4: Pilot-scale PHA fermentation Pilot-scale PHA production, including both 50 L using glycerol waste and 100 L using FOG and VFAs will be performed by applying further optimized fermentation parameters, fermenation media, and feeding strategies. A postdoc from University of Missouri will be stationed onsite in the pilot lab at Virginia Tech to work with VT graduate students to conduct pilot-scale PHA production. Objective 5: PHA extraction and purification The HMP-based PHA extraction and purification process will be optimized to improve PHA recovery rate and PHA purity on H. mediterranei and pseudomonas strains. The physical and chemical properties of the extracted PHAs from different processes and strains will be characterized. Objective 6: Biomanufacturing and characterization of PHA-derived plastics Prototypes of rigid packaging system with both types of PHAs (scl-PHAs and mcl-PHAs) produced in this project will be produced and used as an additive to enhance mechanical properties of commercially available PHAs. Multiple combinations with other bioplastics will be tested for understanding the properties and functionalities in terms of packaging systems. Objective 7: Iterative TEA and LCA to improve and judge the success of this project The assessment and sensitivity analysis will be completed. The team will also begin evaluating specific scenarios for the biorefinery deployment in the U.S. locations and evaluate supply chain configurations.

Impacts
What was accomplished under these goals? Objective 1: Food waste inventory check and characterization Food wastes samples were collected from food processing companies, biodiesel facilities and restaurants. Food waste characterization, including TS, VS, pH, COD, total nitrogen, ammonia nitrogen, phosphorus, and minerals, were analyzed following standard methods ASTM STP 1282. All the samples were prepared, shipped, and measured following the protocols. Particle size distribution of the food waste before and after wet grinding was also measured. Objective 2: Modular design of the pilot scale system QEG has designed the modular pilot-scale bioprocessing system based on the inputs from the PD and Co-PDs. The modular design at the pilot scale includes both new and existing bioreactors and tanks from QEG, VT, and UM. The UM 130-liter fermenter has been refurbished and delivered to the VT pilot facility. A 50-liter glass fermenter was purchased by Quasar for the fermentation using halophilic strains (e.g., Haloferax Mediterranei) due to the high salinity substrates. The bioreactor was delivered to VT and has been used for pilot scale testing. VT has purchased a 100-L bioreactor for dark fermentation, a disc centrifuge for PHA recovery, and a high-pressure homogenizer for PHA extraction. We have also compared the separation efficiency between disc centrifuge and membrane separation in terms of PHA recovery, energy consumption, and solids residues in the permeate. We have all the key components for PHA production from food waste via the proposed pathways. After pilot scale testing, quasar will modify the modular design based on the testing results, which can be used for the engineering design of the commercial scale system. Objective 3: Pilot-scale demonstration of VFA production We have designed and manufactured a 100 L pilot-scale anaerobic digester with variable mixing speed and temperature. The stainless steel reactor has been delivered and set up at Virginia Tech for pilot scale VFA production through dark fermentation. Meanwhile, a 30 L anaerobic digester has been operated in the dark fermentation mode for three months to demonstrate stable VFA production and also provide seed sludge for the pilot-scale anaerobic digesters. VFA production with high yield has been achieved in the 30 L anaerobic digester. Objective 4: Pilot-scale PHA fermentation The 130 L fermentor was refurbished and commissioned for the pilot scale testing. The fermentor was converted from its orginal version for cell culture by replacing the existing Mass Flow Controller and motor and fully diagnosed for functioning condition. The upgraded pilot scale fermentor has been delivered to Virgin Tech and is for pilot-scale testing and demonstration. Meanwhile, the first round of 50 L PHA fermentation has been accomplished by using H. Mediterranei and glycerol waste generated from biodiesel industry as feedstock. The cellular PHA content in H. Mediterranei achieved was as high as 61.03% cellular volital solids. In parallel, fermentation technology has also been optimized for upscaled production of medium-chain-length PHAs (mcl-PHAs) using pseudomonas strains and waste cooking oil, a representative feedstock of fat, oil, and grease (FOG) as a feedstock. Two routes have been developed to achieve this PHA fermentation, i.e., direct oil conversion and oil-hydrolyzed fatty acids conversion. Both routes reached industrially relevant cell titers (50-150 g/L) with substantial PHA accumulation. For VFAs to PHA conversion, inhibitory effects of VFAs (C2-C6) and various co-substrates have been identified. It was found that glycerol as a food-waste relevant substrate could potentially help overcome inhibitory effects of VFAs for achieving high PHA yield. These outcomes provided critical baseline data and optimized fermention parameters for scaling up in the 130 L pilot-scale fermenter. Objective 5: PHA extraction and purification A new pilot-scale disc-stack centrifuge has been installed to separate bacterial cells from fermentation broth. A tangential flow filtrationmembrane instrument is being tested to concentrate bacterial cells for downstream processing. A new two-stage high pressure homogenizer has been acquired to break the cell walls of bacterial cells to releasing PHAs from cells. A high pressure homogenization (HMP) -based downstream process was developed to break the bacterial cell walls for extracting PHA from the fermentation broth. This method avoids the heavy use of environmentally toxic chemicals and potentially reduces the carbon footprint and the cost of PHA extraction and purification. By using the HMP-based extraction technique, we have been able to extract over 80% of PHA with 80% of purity from H. mediterranei. Objective 6: Biomanufacturing and characterization of PHA-derived plastics Using commercially available PHAs as a reference for method development, a new multilayer film structure has been successfully developed using a spray coating method leveraged from Dr. Kim's lab. Amorphous PHA (aPHA, CJ Biomaterials) shows elastomer behavior, and it is a typical property of mcl-PHAs in this project. We confirmed the amorphous type of PHA can be easily compounded with both crystalline and semicrystalline types of commercial PHAs and be compatible with the novel spray coating manufacturing process. Furthermore, this elastomer behavior can play the role of plasticizer in bioplastic packaging systems. Objective 7: Iterative TEA and LCA to improve and judge the success of this project The baseline Techno-Economic Analysis (TEA) model has been developed, assuming a plant capacity of 450 metric tons per day. The initial assessments for both fixed capital investment and operating costs have been completed. The fixed capital investment is assessed to be $77 million, with operating costs amounting to $70 million. The minimum selling price for PHAs has been calculated to be $3.67 per kilogram. Equipment expenditures account for $28 million in capital expenses, with the anaerobic digester and fermenter accounting for the majority of that amount. For Operating Costs, utilities and raw materials constitute the major expenses. An initial sensitivity analysis was also performed, which revealed that PHA yield is the most sensitive parameter.

Publications

  • Type: Journal Articles Status: Published Year Published: 2023 Citation: Ge, X., Chen, Y., S�nchez i Nogu�, V. and Li, Y., 2023. Volatile Fatty Acid Recovery from Arrested Anaerobic Digestion for the Production of Sustainable Aviation Fuel: A Review. Fermentation, 9(9), p.821.
  • Type: Book Chapters Status: Accepted Year Published: 2024 Citation: 1. Ge X., Tanvir R. U., Hu, Z., Hassanein A., Lansing S., Yu. Z., Luo, H., Wang Z.. Wan, C., Yang. L., Khanal, S. K. , Li, Y. 2024. Rethinking Anaerobic Digestion for Bioenergy and Biopolymers Production: Challenges and Opportunities. Advances in Bioenergy. Vol 9.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2023 Citation: Wan, C., Mudiyanselage, K.M. 2023. Bioupcycling of Waste Streams into Polyhydroxyalkanoates: Opportunities and Challenges. 4th International Conference on Bioresource Technology for Bioenergy, Bioproducts & Environmental Sustainability, May 14-17, 2023, Lake Garda, Italy, invited plenary talk. Mudiyanselage, K.M., Yisheng Sun, Wan, C. 2023. Waste to Bioplastics: Medium?chain Polyhydroxyalkanoates from Waste?derived Organic Acids. Poster, ASABE, July 9-12, Omaha, NE. Zhang X.Y., Amradi N., Hassanein A., Lansing S., Wang Z.W., (2023) Salty food waste conversion to bioplastics. WEFTEC 2023, Sep.30  Oct. 4, Chicago, IL Zhang X.Y., Amradi N., Hassanein A., Lansing S., Wang Z.W., (2023) Bioplastic production from salty food waste. WaterJAM 2023, September 11-14, Virginia Beach, VA Zhang X.Y., Amradi N., Hassanein A., Lansing S., Wang Z.W. (2023) Bioplastic production from food waste. 2023 ASABE Annual International Meeting. July 9  12, Omaha, NE, USA Zhang X.Y., Amradi N., Hassanein A., Lansing S., Wang Z.W., (2023) Salty Food Waste Conversion to Bioplastics. WaterJAM 2023, September 11-14, Virginia Beach, VA Zhang X.Y., Amradi N., Hassanein A., Lansing S., Wang Z.W. (2023) Conversion of salty food waste to bioplastics. AEESP Research and Education Conference 2023, June 20-23, Boston, MA Zhang X.Y., Amradi N., Hassanein A., Lansing S., Wang Z.W. (2023) Bioplastic production from salty food waste. WEF/IWA Residuals and Biosolids Conference 2023, May 16-19, Charlotte, NC
  • Type: Websites Status: Published Year Published: 2023 Citation: Luke Weir, At Virginia Tech, research is turning food scraps to bioplastic, Jan 16, 2023, Virginia Tech Daily News. https://roanoke.com/news/local/education/at-virginia-tech-research-is-turning-food-scraps-to-bioplastic/article_0f190a3a-905f-11ed-8541- bf88d73dc905.html Sabine Waldeck , US researchers land US$2.4M to turn food waste into affordable bioplastics, 19 Jan 2023, Packaging insights, https://www.packaginginsights.com/news/us-researchers-land-us24m-to-turn-food-waste-into-affordable-bioplastics.html#:~:text=The%20researchers%20use%20microorganisms%20to,can%20be%20processed%20into%20bioplastics. Maya Rodriguez, Researchers turning food waste into biodegradable plastic, Aug 29, 2023, Scripps News, https://scrippsnews.com/stories/researchers-turning-food-waste-into-biodegradable-plastic/ Luke Weir, Virginia Tech research is turning foodscraps to bioplastic, January 21, 2023, The Washignton Post Mizzou engineering researcher helps turn food wastes into biodegradable plastics. March 10, 2023. https://engineering.missouri.edu/2023/mizzou-engineering-researcher-helps-turn-food-wastes-into-biodegradable-plastics/