Description:
OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Weapons, Information Systems
OBJECTIVE: The goal of SaFE is to develop practical; low-cost; small size, weight, and power; non-isotopic sources for food irradiation and other applications requiring pathogen sterilization, supporting ubiquitous treatment at points of production and points of distribution, particularly in austere or compromised environments (e.g., expeditionary operations, humanitarian relief, or disaster response).
DESCRIPTION: This SBIR XL topic will focus on the development of compact, low-cost, high efficiency, and economically viable electron accelerator systems. The topic is composed of two linked subtopics: Subtopic 1 will develop accelerator technology, and Subtopic 2 will focus on distributed system designs and pilot demonstrations.
Accelerators developed as part of the first subtopic will be capable of generating continuous, high current electron beams at 2 to 10 MeV energies using 10 kW electric sources. 10 kW generators are commonly used in deployed support operations such as those found in containerized kitchens. Specifically, this subtopic will explore recent innovations resulting in accelerator designs that can be produced for tens of thousands of dollars compared to millions of dollars for traditional high power accelerators such as Rhodotrons and S-band LINACs, while being suitable for new distributed system architectures. High-gradient direct current (DC) accelerator structures, novel voltage multiplier designs, and new innovations in dielectric materials may provide viable technical approaches. Further, new solid state amplifiers could provide a potential path for radiofrequency (RF) approaches. Such configurations could present the highest potential for compact, low-cost, high wall-plug efficiency accelerator designs.
The second subtopic, system studies, will initially focus on two use cases: (1) a single 10 kW system for deployed or austere environments and (2) multiple distributed 10 kW systems for point of packaging applications. Subtopic 2 performers will conduct detailed economic analysis including capital costs and operations and maintenance costs. The analysis will define minimum viable product and systems characteristics that can be economically produced and address the maximum number of applications for wide-spread use while still achieving treatment and throughput requirements. Further, practical issues such as radiation shielding, automation, and regulatory concerns will be addressed. These analyses will be informed by strong food industry, U.S. Army Natick Soldier Center, Food and Drug Administration (FDA), and U.S. Department of Agriculture (USDA) engagements. Systems work will culminate in a proof-of-concept pilot demonstration of the specific subtopic accelerator technology. Such a demonstration aims to establish broader adoption of food irradiation and enhance food safety and security for both deployed and domestic applications. In addition, secondary applications such as sterilization and remediation will be examined.
It is envisioned that between the two subtopics, technical, economic, and regulatory hurdles currently hindering food irradiation adoption will be fully addressed. This, in turn, will jumpstart commercial activity in this sector leading to viable products, new industrial development, and overall greater food safety and security.
PHASE I: This topic is soliciting Direct to Phase II (DP2) proposals only. There is no Phase I; however, proposers must provide evidence of approach feasibility with results at a level commensurate with the conclusion of a Phase I effort. Examples of such evidence are included below for each subtopic.
Proposers to Subtopic 1 are required to provide documentation outlining success in high efficiency accelerator component technologies. Achievements must be substantial. For example, a key component for a DC accelerator could be a Cockroft-Walton voltage ladder. Such a ladder showing 1 MV and an efficiency of >70% into a representative load would be considered sufficient.
Proposers to Subtopic 2 are required to provide documentation outlining success in prior end-to-end system design, demonstration of hands-on work with analogous technologies (including core competencies with accelerator technologies), and experience working with regulatory agencies – specifically the FDA and state regulatory bodies for machine-produced radiation sources.
PHASE II: SaFE is composed of two linked subtopics over an anticipated 3-year period of performance. The period of performance is divided into a 12-month base and two 12-month option periods. Proposers may apply to one or both subtopics.
Subtopic 1: Accelerator technology development. The overall goal of Subtopic 1 is to produce and demonstrate a turn-key high efficiency, low cost, reasonably compact, irradiation accelerator prototype at technology readiness level 6 with the following characteristics:
Parameter Threshold Objective
Tunable electron energy range (MeV) 2-5 2-10
Max x-ray energy (MeV) 5 7.5
Wall plug efficiency (Pbeam/Pwall) > 0.3 > 0.7
Unit cost ($) < $100,000 < $50,000
The accelerator must make use of 10 kW electric generator output such as 120V@100A or 208V@50A. The complete, turn-key system including controls, accelerator, RF generation (if appropriate), shielding, beam steering, and target must be compatible with a single 463L pallet. Additional suitability metrics include a removable x-ray converter (such as tantalum) to support x-ray production, continuous or near continuous operation, and targets compatible with conveyer-based operations.
The 12-month base period will focus on accelerator design, modeling, and component development. The design will progress through typical processes including a system requirements review, preliminary design review, and a critical design review. Components will be developed and tested supporting the overall accelerator design.
Base period (12 month) milestones:
• Month 1: Kickoff materials. Slide deck summarizing technical approach to meet overall goals, risks, and risk mitigations and quantified milestone schedule
• Month 3: System Requirements Review
• Month 6: Preliminary Design Review
• Month 12: Critical Design Review
During the 12-month Option 1 period, components will be refined and integrated into a prototype system. This system will be tested to verify performance and ultimately used in Subtopic 2’s pilot system demonstration.
Option 1 period (12 month) milestones:
• Month 6: Complete Accelerator Prototype
• Month 9: Test and Eval of Prototype
• Month 10: X-ray Target Assessment
• Month 12: Integrated T&E of Prototype
During the 12-month Option 2 period, support will be provided to Subtopic 2’s pilot system demonstration and the accelerator will be further refined to a minimum viable product using feedback from Subtopic 2.
Option 2 period (12 month) milestones:
• Month 6: Accelerator Integration Report
• Month 12: Final Accelerator and System Design
Monthly written technical progress reports will supplement the above milestones (see template under SBIR/STTR BAA DOCUMENTS at https://www.darpa.mil/work-with-us/for-small-businesses/participate-sbir-sttr-program).
Subtopic 1 performers are expected to collaborate with subtopic 2 performers in this program.
Subtopic 2: Irradiation system design and proof-of-concept pilot demonstration
Subtopic 2 will complete system studies for two use cases using the accelerator technology of Subtopic 1. As mentioned above, the first use case will examine operation in deployed or austere environments. Food-based logistical support aims to feed 300 troops from mobilized trailers or 800 troops from containerized kitchens. About 32 lbs. of food supplies (including packaging) are needed per troop per week. This is about 2 kg/day at an average density of ~0.5 g/cc. Detailed modeling and analysis will be carried out on various objects and package configurations, and optimization studies will be conducted to provide effective treatment per object at maximum throughput. In addition, Monte Carlo analysis will be used to study radiation shielding. Such shielding could make use of supplied or indigenous materials or combinations of both to minimize size and weight. Handling systems will also be developed and included in the design studies. Metrics for this use case are described in the table below.
Parameter Threshold Objective
Size and weight (463L pallets) < 2 < 1
Throughput (kg/hr) > 50 > 180
Dose/item (kGy) > 0.4 > 1
Dose uniformity ratio < 2.5 < 1.4
Size and weight metrics include the full accelerator of Subtopic 1. Object and packaging details as well as feedback on aspects of practical system suitability are anticipated through discussions with performer(s) and DoD stakeholders during the base period.
The second system study will examine using the accelerator of Subtopic 1 in a distributed architecture at the point of packaging. Perishable food such as lettuce or ground beef and associated packaging will be analyzed. Detailed technical analysis, economic analysis, and commercialization plans for the system will be completed with the goal of minimizing overall system costs. The specific use case will be proposed by the performer. Metrics for this use case are described in the table below.
Parameter Threshold Objective
Throughput (kg/hr) > 1,000 > 3,600
Dose (kGy) > 0.4 > 1
Dose uniformity ratio < 2.5 < 1.4
In addition to system studies, Subtopic 2 will develop and demonstrate a proof of concept pilot for both of the use cases described above. This includes addressing all regulatory requirements and potentially crafting petitions to regulatory bodies describing the specific needs of distributed systems.
The 12-month base period will focus on separate design studies for the use cases described above and progress through typical design review elements, including a system requirements review and preliminary design review. In addition, all relevant regulations will be identified.
Base period (12 month) milestones:
• Month 1: Kickoff materials. Slide deck summarizing approaches to meet overall goals, risks, and risk mitigations and quantified milestone schedule
• Month 3: System Requirements Review
• Month 9: Preliminary Design Review
• Month 12: Final base period report and design update
During the 12-month Option 1 period, systems will be refined through a critical design review. A minimum viable product will be defined for the accelerator system of Subtopic 1. Pilot plans will be progressed and address all regulations.
Option 1 period (12 month) milestones:
• Month 3: 1) Critical Design Review, including summary of minimum viable product findings for accelerator technology, and 2) Preliminary pilot plan
• Month 6: Interim pilot plan
• Month 12: Final pilot plan
During the 12-month Option 2 period, the accelerator from Subtopic 1 will be used to complete a concept pilot demonstration.
Option 2 period (12 month) milestones:
Month 3: Initial pilot operation report
Month 6: Interim pilot operation report
Month 12: Final pilot operation report
Monthly written technical progress reports will supplement the above milestones (see template under SBIR/STTR BAA DOCUMENTS at https://www.darpa.mil/work-with-us/for-small-businesses/participate-sbir-sttr-program).
Subtopic 1 and 2 are linked. Monthly coordination meetings between the teams are anticipated to facilitate communication and successful completion of overall program goals.
PHASE III DUAL USE APPLICATIONS: While the U.S. food supply is among the safest in the world, the FDA estimates that there are about 48 million cases of foodborne illness annually—the equivalent of sickening 1 in 6 Americans each year. And each year these illnesses result in an estimated 128,000 hospitalizations and 3,000 deaths. More significantly, the USDA estimates that food waste is between 30 and 40 percent of the U.S. food supply, with spoilage being a significant contributor. Based on estimates from USDA’s Economic Research Service of 31 percent food loss at the retail and consumer levels, this corresponded to approximately 133 billion pounds and $161 billion worth of food in 2010. Globally, about 1.4 billion tons of food is wasted every year. From a food security perspective, the U.S. imports 94% of its seafood, 55% of fruit, and 32% of vegetables, while the FDA is only able to inspect 1-2% of these foodstuffs. Lastly, there is a need to treat food for improved safety and stability during expeditionary operations or in environments where food quality may be compromised, such as in disaster response or humanitarian relief operations. Development of “in-house,” port-of-entry, or expeditionary irradiation capabilities would provide a new means to avoid or significantly improve these food safety and waste issues. For food safety applications, the availability of in-house technologies will help reduce and control costs, provide greater flexibility in managing inventory, facilitate new product formulations, protect against supply chain disruption, and decrease the impact of waste management. Being able to cold pasteurize food at points of production, import, or distribution and in austere environments could present a transformational ability to improve food safety and security and reduce the threat from natural, accidental, or intentional food contamination. Further, these sources could also be used for a range of other applications. For example, low-cost e-beam technology can be employed to remediate urgently needed capabilities to degrade per– and polyfluoroalkyl substances (PFAS) in groundwater and soils. In-situ sterilization of medical devices is a further need for such sources. Overall, advancement in improving food safety, availability, and security could have global impacts and significantly advance U.S. national security agendas. By enabling safe and secure food supplies in underdeveloped countries, there are new opportunities for the U.S. to provide additional stability in these regimes.
Successful proposals for this SBIR offering must make significant arguments supporting the commercial viability of their approach. Hence, proposals to Subtopic 1 must provide initial evidence that their technical approach will allow accelerator structures that are much lower cost to produce (>10-100x) and operate (>10x) than traditional accelerator systems such as S-band LINACs and rhodotrons, while still achieving required beam powers for high throughput food treatment. Proposals for Subtopic 2 must make arguments that, should the above accelerator technology be available, it would enable highly economic treatment of foodstuffs at points of production/packaging and ports of entry. Transition and commercialization (T-C) milestones have been added as part of the option phases to aid in assuring commercial viability.
REFERENCES:
1. https://www.aiche.org/resources/publications/cep/2016/november/introduction-electron-beam-food-irradiation
2. https://www.armytimes.com/news/your-army/2019/10/07/the-plan-to-give-soldiers-a-days-worth-of-mres-in-one-ration-seven-days-of-food-weighing-less-than-10-pounds/
3. https://www.fda.gov/food/consumers/what-you-need-know-about-foodborne-illnesses#
4. https://www.usda.gov/foodwaste/faqs#
5. https://www.rts.com/resources/guides/food-waste-america/
6. https://www.ers.usda.gov/amber-waves/2022/february/india-and-mexico-top-sources-of-pathogen-based-u-s-food-import-refusals/
7. https://doi.org/10.1016/j.radphyschem.2021.109705
8. https://www.osti.gov/servlets/purl/1774110
KEYWORDS: Food irradiation, cold pasteurization, medical sterilization, x-rays, linear accelerators, radiation dose
