(591c) Characterizing and Modeling of Particle Size Distributions from Propellant Open Burning or Open Detonation (OB/OD)

The US Department of Defense (DoD) demilitarization activities conducted at the Utah Test and Training Range (UTTR) include destruction of ballistic missile motors, which contain solid propellants, by open burning or open detonation (OB/OD). Detonations and burns of these solid propellants generate alumina-based particulate matter (alumina particulate) as an emission. Airborne particulate matter (PM) generated by OB/OD, such as PM2.5 (any PM with a diameter less than or equal to 2.5 microns) and PM10, is regulated as a pollutant emission. The data historically used for permitting activities at the UTTR do not provide test-based particle size information (fraction of PM2.5 and PM10), and no modeling approach is known for the prediction of particle size distributions (PSDs) or PM emission rates.

A predictive particle model was developed with two primary components: the Cheetah combustion model, and a MATLAB stochastic particle model. The predictive particle model uses an incremental time step approach to address nucleation, coagulation, and surface growth of alumina particulate in the detonation plume.

Laboratory work has been performed to validate sampling methodologies for measurement of pollutant emissions and PSDs from solid propellant OB/OD at the Utah Test and Training Range. Preliminary PSD and PM emission rate data have been acquired for small-scale burns of a surrogate propellant. Sub-scale detonation data will be used to refine and validate the particle prediction model.

These initial project phases are directed towards development of a data set to support a model of OB/OD phenomena that is acceptable to regulators and is sufficient to predict environmental emissions.