Sampling is a difficult but essential part of the coal production process. ASTM International Committee D05 on Coal and Coke hopes to streamline that process with the publication of new standard D 7256/D 7256M, Practice for Mechanical Collection and Within-System Preparation of a Gross Sample of Coal from Moving Streams. Practice D 7256/D 7256M is under the jurisdiction of Subcommittee D05.23 on Sampling.
Coal is hard to sample for a variety of reasons. The composition of coal can vary widely from noncombustible particles to those that can be burned completely. Other complicating factors are the type of sampling equipment available, the quantity to be represented by the sample and the degree of precision required. Despite these difficulties, the data obtained from coal sampling is essential for establishing price, controlling mine and cleaning plant operations, allocating production costs and determining plant or component efficiency.
“Most commerce in coal is governed by mechanical sampling for both quality control and payment at some point in the process,” says Paul Reagan, Sampling Associates International. “However, due to the historical evolution of the sampling standards within ASTM, the rules governing the mechanical sampling of coal were contained in a number of different standards, most notably D 2234, Practice for the Collection of a Gross Sample of Coal, and D 2013, Practice for Preparing Coal Samples for Analysis.” Practice D 7256/D 7256M now contains these mechanical sampling rules within one standard.
Reagan notes that Practice D 7256/D 7256M will be an important standard for quality control personnel at coal mines, power plants, steel mills and other industrial locations, as well as at independent testing organizations.
Subcommittee D05.23 plans to continue refining the methods covered in Practice D 7256/D 7256M and invites any interested parties to participate in future revisions of the standard. “Participation by the key players in the industry is critical to the quality of the standards produced,” says Reagan. Reagan also points out that a separate task group maintains another important mechanical sampling standard that those in the industry should be familiar with, D 4702, Practice for Quality Assurance of a Mechanical Sampling System.
ASTM International standards are available for purchase from Customer Service (phone: 610/832-9585; email@example.com) or at www.astm.org. For further technical information, contact Paul M. Reagan, Sampling Associates International, Newport News, Va. (phone: 757/928-0484; firstname.lastname@example.org). Committee D05 meets Oct. 22-25, at the October Committee Week in Atlanta, Ga. For membership or meeting information, contact Scott Orthey, manager, Technical Committee Operations, ASTM International (phone: 610/832-9730; email@example.com).