ASTM D6970

Collection of Calcined Petroleum Coke Samples for Analysis

Applicability: ASTM D6970 applies to calcined petroleum coke (CPC) used as a primary raw material in the manufacture of carbon anodes for aluminum smelting and graphite electrodes for electric arc furnaces. It covers the collection of representative samples from bulk lots including conveyor belts, bucket elevators, pneumatic transfer systems, and stockpiles. The practice is specific to calcined material and is not intended for sampling green (uncalcined) petroleum coke or other carbonaceous feedstocks covered by separate ASTM sampling practices.

Purpose: ASTM D6970 establishes systematic procedures for collecting representative bulk samples of calcined petroleum coke using increment-based sampling from moving streams or stationary lots, with guidance on the number and frequency of increments required to achieve representative sampling precision for the lot size. Proper sample collection is the critical first step in ensuring that subsequent analytical determinations of real density, electrical resistivity, sulfur and vanadium content, and Vibrated Bulk Density (VBD) are representative of the entire lot and support acceptance testing by carbon and graphite electrode manufacturers.