ASTM D7582

Proximate Analysis of Coal and Coke by Macro Thermogravimetric Analysis

Applicability: This procedure applies to the determination of moisture and the inorganic residue as ash in the analysis of coal, coke, soil, solid fuels, and solid waste samples received or generated by Conti Testing Laboratories, Inc. (CTL), Pittsburgh, Pennsylvania. Volatile Matter is not being determined on the TGA’s at this time.

Purpose: In thermogravimetric analysis, the mass of a sample in a controlled atmosphere is recorded repeatedly as a function of temperature or time, or both. A sample size of approximately 1 g is used while the temperature is normally ramped from ambient to a specific temperature and held at that temperature for a prescribed length of time. The mass change is recorded repeatedly during the entire procedure. The samples for moisture and ash analyses are complete when the sample reaches a constant mass as defined in the instrumental operating parameters. Moisture is determined by measuring the loss in mass of the sample when heated under specified conditions of temperature, time, atmosphere, and equipment specifications. Ash is determined by measuring the mass of the residue remaining after burning the sample under specified conditions of temperature, time, atmosphere, and equipment specifications. Moisture and ash can be determined sequentially or in separate determinations.