skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Investigation of mechanics of mine acid formation. Volume 1

Technical Report ·
DOI:https://doi.org/10.2172/5358807· OSTI ID:5358807

The objective of the contract was to determine, by the combination of laboratory experiments and mine samplings, the kinetics and mechanisms of the various reactions that produce mine acid drainage. To achieve this goal, primary investigations were performed utilizing pure iron disulfide in the form of pyrite and marcasite, free from coal. The effects of temperature, concentration, surface area, media nature, oxygen, presence of additional ions and bacterial action with respect to dissolution rates were measured. Thiobacillus ferrooxidans and T. thiooxidans were included in this study, both as purchased cultures and freshly isolated from mine samples. Mine samplings were performed to determine the type and quantity of bacteria present, the effect of weathering upon coals' propensity to produce acid and other drainage, the effect of other minerals and the nature of the mine water upon ion liberation, and the effect of the different kinds of bacteria upon the above process. It was established that both pyrite and marcasite, provided sufficient surface area is exposed, will produce hydrogen, sulfate, and iron ions. This process is accelerated in the case of pyrite and marcasite by the presence of T. ferrooxidans and ferric ions. T. thiooxidans accelerates marcasite solubilization and the dissolution of iron disulfide present in coal, but had no effect on museum grade pyrite.

Research Organization:
Ultrasystems, Inc., Irvine, CA (USA)
DOE Contract Number:
ET-78-C-01-8977
OSTI ID:
5358807
Report Number(s):
FE-8977-T1
Country of Publication:
United States
Language:
English