STP661: Correlation of Weathered Lignite with pH and Depth of Cover

    Ginnard, KJ
    Project geologist and vice president, Paul Weir Company, Chicago, Ill.

    Corriveau, MP
    Project geologist and vice president, Paul Weir Company, Chicago, Ill.

    Pages: 9    Published: Jan 1978


    Abstract

    Using the well known relationship of lowered pH with increased oxidation of lignite slurries, a rapid field technique was established correlating the pH of a sample lignite slurry and its depth of cover to the degree of oxidation (or weathering).

    Four relationships were confirmed: (a) calorific content decreases with increased oxygen content, (b) increasing cover corresponds to decreasing oxygen content, (c) megajoule (Btu) content increases with depth of cover, and (d) megajoule (Btu) content increases with corresponding increase in pH of lignite slurry.

    Using this technique and the relationships derived therefrom, a field geologist can quickly estimate as a first order approximation from the depth of coal times pH product whether or not a sample lignite is unacceptably weathered.

    Keywords:

    coal, lignite, weathering, pH, oxidation, field


    Paper ID: STP35765S

    Committee/Subcommittee: D05.28

    DOI: 10.1520/STP35765S


    CrossRef ASTM International is a member of CrossRef.