The objective of this topic is to seek proposals to demonstrate and validate alternative cleaning methods and alternative solvents for use in the maintenance cycle of DoW assets, including cleaning and surface preparation, application, and removal of adhesives, sealants, and coatings.
The alternative cleaning method and solvent alternative should have the following general characteristics:
- Eliminate or significantly reduce the use of chemicals with risk evaluations under TSCA1 for a targeted application.
- Reduce or eliminate the use of CERCLA hazardous substances.
- Not contain the use of per- and polyfluoroalkyl substances (PFAS), perfluorinated oligomers, and polymers or other chemicals or materials that have been the subject of extensive replacement and/or cleanup efforts.2
- Reduce or eliminate hazardous air pollutant (HAP).
- Reduce or eliminate volatile organic compound (VOC).
- Maintain low flammability or reduce flammability.
- Reduce the risk of harmful workplace exposures and the need for personal protective equipment (PPE).
- Cause no damage to or degradation of the substrate material.
- Alternative solvents for a targeted application must be compatible with the substrates used. Substrates include steel, aluminum, titanium, or magnesium alloys or polymer matrix composites, depending on the application.
- Alternative solvents should be relatively safe with lower toxicity relative to the incumbent solvent.
- Alternative solvents should be scalable and relatively cost effective.
- Equipment for alternative cleaning methods should be able to fit within a DoW production line.
- Additional specific characteristics for targeted DoW application should be identified in the proposal, rationale for the alternatives to meet those requirements should be provided, and work to develop the solvents to meet those requirements should be proposed. Example key requirements are repainting effectiveness (time required and percent removal) and no increases in susceptibility to hydrogen embrittlement.
The project must demonstrate that the commercial solution is less impactful to the environment relative to the currently used technology. The project must also demonstrate that the technology will result in reduced cost to maintain the weapons system or platform while also having reasonable initial acquisition costs.
The materials and processes to be demonstrated/validated should already be developed to a minimum Technology Readiness Level (TRL) of 4, and the proposed project should bring them to TRL 7 or higher. Field testing in military depots on general military weapons systems and platforms components, parts, sub-systems, or sections should be included in the proposed project. Alternative solutions should be production-level materials rather than laboratory-scale samples. Projects must demonstrate producibility, defined as the ability to be produced in the near term to meet the current weapons systems and platforms requirements.
For solvent formulations, proposals should include an assessment of the human health and environmental impacts of proposed ingredients, formulations, and byproducts if such testing has not already been completed. Any completed testing on human health and environmental impacts of the corrosion inhibiting formulations components and formulations should be summarized in the proposal. Proposals should also include a plan to conduct an appropriately-scaled life cycle analysis3,4 to inform financial decisions regarding incumbent and alternatives to aid in technology transition.
The project team must include DoW personnel or DoW prime contract companies that manufacture DoW weapons systems and platforms and are considered stakeholders for the intended application. Proposals should indicate the involvement of other DoW stakeholders at the consultant level and higher.
Identifying and developing alternatives to currently used cleaning methods and solvents would reduce supply risk to DoW operations and lead to improved process viability, including reduced time and costs associated with personal protective equipment usage and facility controls. Reducing hazardous emissions can lead to increases in production throughput to enable increased readiness.
Solvents are used in various aspects of the maintenance cycle, including cleaning and surface preparation, application, and removal of adhesives, sealants, and coatings. Solvent usage is applied to small parts, medium-sized parts, and large parts or sections of weapons systems. Cleaning can be performed via dip tank, vapor degreasing, spray applied, or hand applied via cleaning rag. Solvent-based coatings, adhesives, and sealants are applied by spray, caulk tube applicator, and roll on methods. Solvent-based coating removal can be performed via dip tank, spray applied, or hand applied. Adhesive, sealant, and coatings are typically governed by military or commercial specification requirements. Solvents that are chosen must be compatible with those specifications, or a path needs to be identified to enable revision of the relevant specification to enable use of alternative solvents.
Examples of regulated solvents include methylene chloride, trichloroethene (TCE), tetrachloroethene (PCE), dichloroethene, d-limonene, methyl isobutyl ketone, N-methyl pyrrolidone, benzene, toluene, and xylene.
