A pilot scale test program was conducted to evaluate the size reduction performance of HPGR (High Pressure Grinding Rolls) operating in different circuit configurations. For this purpose a series of pilot-HPGR locked cycle tests were performed with medium and high pressures to simulate the HPGR operation in closed circuit with a screen, with partial product recycle, and with edge recycle. Logged instrumentation data such as roller speed, working gap, operating pressure, and power draw were used in combination with material test results such as particle size distributions, flake density, flake thickness, and bulk density of the feed for calculation of HPGR operational parameters. The paper reports the results from the pilot HPGR test work. The analysis reported herein includes an evaluation and comparison of different circuit configurations of the HPGR operation in terms of energy consumption, capacity and product fineness and also discusses the benefits of various circuit arrangements.
comminution; HPGR; classification; circuit configuration