Characterization of Emissions from Laser Ablation of Painted Surfaces
Recycling can have unintended air quality and human exposure impacts. An industrial packaging company planned to use laser ablation to prepare painted steel drums for recycling and reuse. However, they were concerned about possible human health or environmental risks associated with the laser ablation process. They needed fast answers to understand their potential risks and ensure that their process would meet regulatory emissions standards.
Battelle was able quantify emission factors for volatile, semivolatile, and particulate species generated during the laser ablation of the paint from drums. First, we gathered baseline air quality data without activating the laser ablation process. Then, we collected emissions during laser ablation of five different paints and coatings using stainless steel sampling probes positioned directly above and downstream from the ablation process. We looked for four types of emissions: carbonyls, volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), and particle-bound metals. We were also able to estimate the particle size distribution (PSDs) of the combustion effluent from the metals sample. Analysis was completed using mass spectrometry, high performance liquid chromatography, and low resolution GC/MS with multiple ion detection (MID).
We ultimately analyzed concentrations of 22 different metals, 63 VOCs, 3 carbonyl compounds and 18 PAHs both before and during the ablation process. As a result, we were able to quantify the increase in concentration for each specific metal or compound as a result of the laser ablation process. We identified several species that could present health or environmental risks and pose problems for regulatory compliance.
This quick turn-around study demonstrated possible regulatory risks involved with the laser ablation process. The company was able to use the study results to inform the selection of a lower risk alternative drum-cleaning method.