ISO 5074

Hard coal — Determination of Hardgrove grindability index

Applicability: ISO 5074 specifies a method for determining the Hardgrove Grindability Index (HGI) of hard coal using a Hardgrove machine, measuring how easily the coal can be pulverized. It applies to hard coals, defined as having a gross calorific value > (moist, ash-free basis), and includes calibration procedures.

Purpose: ISO 5074 specifies the method for determining the Hardgrove Grindability Index (HGI) of hard coal using a Hardgrove machine, which measures how easily coal can be pulverized. It provides procedures for calibrating the test equipment and preparing standard reference samples, essential for optimizing mill operation and designing pulverizers in power plants.