Chemical Additives for Dust Control: What We Have Used and What We Have Learned

Abstract

The Pacific Northwest region of the USDA Forest Service has been using chemical additives for dust abatement for many years. The traditional additives include dust oils, lignin sulfonate, and chlorides. Increased product costs, environmental concerns, and the continual quest for improved performance has led to consideration of other additives, including synthetic polymer emulsions, tall oil emulsions, clay additives, and penetrating asphalt emulsions. Some road tests have been performed to evaluate their suitability and cost-effectiveness. From these tests and experience, it has been learned that lignin sulfonate, chlorides, and clay additives, when properly matched to the site, have a consistent and predictable performance; polymer and tall oil emulsions, based on limited use, have provided inconsistent performance. The reason for this inconsistency has not been addressed other than the speculation that in some situations the additive did not completely cure, that the cured additive may be water soluble, or there might be variability in the quality of the manufactured product.