Many of the processes in the repair and maintenance of military equipment by the repair facilities are inefficient and, at the same time, can lead to environmental impacts resulting from the discharge of hazardous air pollutants and volatile organic compounds (VOC). Life cycle assessments (LCA) can be used to mitigate or reduce these impacts while improving efficiency.
The goals of this project were (1) to apply LCA principles to selected Department of Defense (DoD) operations to identify and test potential technic al solutions to reduce reliance on toxic chemicals and solvents in industrial and DoD operations and (2) to generate a design guide for implementing life cycle principles on environmental, performance, and cost considerations as an aid to decision making.
The following two life cycle impact assessments were performed: (1) chemical agent resistant coating (CARC) painting operations and (2) alternative chemical depainting. The resulting impact assessment gave a good comparative basis to test the application of the methodology at distinct sites, providing key information on the validity of our approach.
The National Risk Management Research Laboratory has tested solvent formulations of propylene carbonate, n-methyl-pyrrolidone (NMP), and non-NMP formulations as possible alternatives for MEK and methylene chloride in aircraft radome and fuselage depainting. Army technology demonstrations showed the potential for significant real reductions in the quantity of CARC paint needed to coat military vehicles and demonstrated the fact that painting operations in the field can vary significantly among installations. A life cycle inventory conducted with the Navy and the Department of Energy identified the environmental effects of selected energetic materials.
Applying LCA methodology to CARC resulted in a series of discoveries concerning upstream and downstream impacts, problems in the field not previously known to the designers, variances in procedures, and potential improvements for the system. For example, when the Army changed over to highvolume, low-pressure (HVLP) guns as a pollution prevention measure years ago, they did experience a decreased use of CARC paint via improved transfer efficiency, but that impact was offset by an increase in organic solvent usage and extended cleaning operations. The result was an increase in VOC emissions from CARC painting operations. The LCA indicated that this may not have been a very good trade-off, particularly since VOC emissions are a major health concern. The LCA identified a new alternative, the turbine HVLP, which dramatically improved transfer efficiencies above those of the conventional HVLP, resulting in a 40 percent reduction in product use. The life cycle cost evaluation identified a savings of $230,000 per year over the conventional HVLP system used at a Ft. Eustis-sized facility.
A life cycle engineering guide is available from the National Technical Information Service library. It represents a guidance document for conducting integrated LCAs of DoD and related industrial operations to improve design and process efficiencies. This project was completed in FY 1998.
Anticipated benefits of this project include the elimination of VOC emissions and methyl ethyl ketone (MEK) from the radome depainting process. While CARC undergoes tests and reformulation to reduce VOC content, this project shall generate guidance with applicability to facility CARC painting operations DoD-wide. Techniques and product improvements were implemented to ensure that more paint meets the truck, generating cost savings and operational efficiency.