MillSlicer PMC Phalaborwa AG Mill Ini4al Installa4on Trends and Results

Transcription

1 MillSlicer PMC Phalaborwa AG Mill Ini4al Installa4on Trends and Results The following items obtained from the first couple days of system installaion are presented in the next several slides: I. PMC Single Page (double sided) Operator s Guide for understanding the new MillSlicer signals. A. Polar Plots are shown that illustrate the toe movement between an empty and full mill. B. The toe 4-20mA signal along with the new inlet, shell and outlet fill level signals. C. A basic control strategy using the toe signal and how to increase/decrease the auto- control set point. II. III. IniIal PMC Trend Data running under manual control the first day of MillSlicer operaion. A. Toe, Inlet, Outlet and Shell Fill level signals along with the usual process control variables. B. Brief ObservaIons. IniIal Trends running under auto- control (using the toe 4-20mA signal) the second day of MillSlicer operaion. A. Toe, Inlet, Outlet and Shell Fill level signals along with the usual process control variables. B. Brief ObservaIons and Summary NW 40 th Terrace, Suite 1 Gainesville, Florida USA

2 Operator s Guide - MillSlicer Polar Plot Toe Posi4on (PMC AG Mill #1 Data) Under- filled Mill 0 o Mill Rota4on Full Mill 0 o Mill Rota4on 90 o 90 o Real- Ime Toe Angle 180 o Toe = 152 o 180 o Toe = 136 o Note: As the mill fills, the load shiks up on the liner. Toe Angle 0 degrees = 4 ma, Toe 360 degrees = 20 ma Shell Fill Level (teal) Toe = 152 o Inlet Fill Level (blue) Outlet Fill Level (green) Toe = 136 o NW 40 th Terrace, Suite 1 Gainesville, Florida USA Water Mill Power Page 1 of 2

3 PMC Operator s Guide MillSlicer Toe Posi4on Auto Control Strategy Toe = 152 o Toe = 144 o Fill Level Signals: Shell (teal) Basic Automa4c Control Strategy: 1. Empty mill start- up set- point for Toe Angle = 145 o. Enter this set point and start auto- feed control. 2. As the mill fills, observe how bearing pressure & power increase over Ime (see trends). 3A. If power or bearing pressure begin to reach their maximum limits, increase the toe set point. i.e. change toe angle set point from 145 o to 147 o. This should now reduce the feed and empty the mill. 3B. If power or bearing pressure are significantly below their maximum limits, decrease the toe set point. i.e. change toe angle set point from 145 o to 143 o. This should now increase the feed and fill the mill. Note: Upon start- up, it is recommended that the operator run the mill in manual control to more quickly bring the mill up to the desired power/pressure operaing point and then switch to auto- control. Page 2 of 2

4 Ini4al MillSlicer Toe and Typical Process Signals 1 st Day Manual Control Only (3 hour Trend Dura4on) Toe Fill Level Signals: Shell (teal) 1. Drops in feed are due to metal detected on the feeder. Metal must be cleared before feeders re- start. 2. Shell vibraion signal (Teal) does not show much variaion over the 3 hour interval. 3. and vibraion signals vary with mill load but remain constrained between 55-80%. The Outlet has the greatest dynamic range and should be able to detect a blockage very quickly. Unfortunately the operator confidence is quite low (and problems with metal in the feed) mean that the mill is typically being run in an under- loaded condiion. 4. Toe shows the greatest variaion of all the new MillSlicer signals.

5 Ini4al MillSlicer Toe and Typical Process Signals 2 nd Day Morning Auto Control (2 hour Trend Dura4on) Fill Level Signals: Shell (teal, top) Toe (orange) Toe, Power & Pressure all show the mill filling while shell and inlet show the mill emptying slowly. 2. Outlet remains relaively constant (no problems). All three vibraion signals run in parallel. 3. Toe set- point for auto control is 146 degrees which we briefly adained so feed was cut and then increased as the Toe increased back up. Note: The actual feed delivered versus the auto control desired amount was found to be many Imes 5-10% off. i.e. Desired 700 TPH, Actual 630 TPH (10% off)

6 Ini4al MillSlicer Toe and Typical Process Signals 2 nd Day AKernoon Auto Control (2 hour Trend Dura4on) Fill Level Signals: Shell (teal, top) Toe (orange) More trouble with the feeders iniially. Auto Control is asking for a conservaive 850 TPH and actual is over 1000 TPH for the clipped periods of Ime. 2. Toe set point for auto control is kept at 146 degrees. We go below this point ager ~30 minutes and so the feed is gradually decreased. Mill Power & are kept away from their max limits and so the control room is impressed. 3. First night of the night shig operator using the new signals, record producion is recorded for the shig % improvement in overall producion since installaion is reported by Ensight mining consultants given the task to opimize power consumpion and producion via new automaion technologies.