Development of coatings for protection of coal during transport and storage. Final report, December 15, 1977--September 15, 1978

Abstract

The use of coatings to prevent dust emissions and leachates from coal stockpiles was studied under sponsorship of the Department of Energy, Division of Environmental Control Technology. The coatings considered included compositions formed of a filler such as pulverized coal and a binder consisting of a combination of waxes and plastics. Various latex emulsions, both with and without fillers, were also evaluated. The purpose of coal coatings is to seal the surface of the stockpile. This prevents water penetration into the coal. By sealing the surface of the pile, dust losses are prevented and leachate formation is minimized. Air circulation through the stockpile is also greatly reduced. This yields the added benefits of reduced oxidation of the coal and prevention of spontaneous ignition. Cold weather handling characteristics of the coal are also improved. Physical properties of the coatings were measured. Included were such characteristics as resistance to water penetration and degradation as a result of thermal cycling. Application techniques were also evaluated. Both hot-applied and cold-applied coatings were considered. Protective coatings appear to be an attractive means of prevention of fugitive emissions from coal stockpiles. The economic benefits from reduced oxidation and improved handling more than off-set the cost ofmore » application. Use of coatings on unit trains or barges may also be attractive.« less