Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Evaluation of the effect of coal cleaning on fugitive elements. Final report: Phase II. Part III. State-of-the-art: fate of trace elements in coal during mining, preparation, and utilization. [1076 references]

Technical Report ·
OSTI ID:5273275

Cleaning is particularly effective in removing those trace elements not associated with the organic fraction of the coal. Elements which often have a high organic association include germanium, beryllium, gallium, titanium, boron, and vanadium. Problem elements that are significantly removed by cleaning include arsenic, chromium, cobalt, copper, fluorine, lead, manganese, mercury, nickel, vanadium, and zinc. The principal release of trace elements to the environment during cleaning is in the drainage from refuse-disposal sites. During coal combustion for power generation, the trace elements present in coal are incorporated into the bottom ash, fly ash, or the flue gas. The degree of partitioning varies with the physical and chemical properties of the element, the type and operating conditions of the combustion unit, etc. In general, mercury, chlorine, bromine, and fluorine are discharged as vapors. Aluminum, barium, calcium, cesium, cobalt, iron, mercury, potassium, lanthanum, magnesium, manganese, rubidium, scandium, silicon, samarium, tantalum, thorium, and thallium show little preferential partitioning between slag or fly ash. Arsenic, cadmium, copper, gallium, molybdenum, lead, antimony, selenium, and zinc are nore concentrated in fly ash. The atmospheric emissions of trace elements resulting from coal combustion are limited to those elements which leave the stack as vapors and those incorporated into that fly ash which is not collected by particulate control devices.Recent evaluations reveal that levels of trace-element emission are at or well below levels considered acceptable and sufficient to protect human, animal, and aquatic life.

Research Organization:
Bituminous Coal Research, Inc., Monroeville, PA (USA)
DOE Contract Number:
AC22-77EV04427
OSTI ID:
5273275
Report Number(s):
DOE/EV/04427-53; COO-4427-53; ON: DE82009852
Country of Publication:
United States
Language:
English