Services

CASE STUDY

Energy Efficiency Survey Asarco, Hayden and Ray Mines, AZ

Situation

Asarco’s Hayden and Ray facilities (each at 35 MW) are actively involved in developing ways to produce energy-intensive copper at a reduced rate. The Hayden facility operates using a concentrator and copper smelter, an oxygen flash furnace, anode casting, oxygen plant, acid plant, and support facilities. The Ray facility operates using an open-pit mine that includes a concentrator, solvent extraction electro-wining operation, and associated support facilities.

To achieve a significant amount of reduction in the energy budget, Lincus was brought on board to analyze the sites’ energy-consumption and identify cost savings opportunities that could be achieved at both the ASARCO Hayden and Ray Mine facilities.

Solution

Lincus started by conducting a preliminary energy-consumption survey of both sites to uncover the best ways for Asarco to reduce utility bills. The energy conservation measures included:

  • Office Lighting System Upgrade
  • Premium Efficiency Motors
  • Oversize cooling tower at the O2 Plant
  • Heat Recovery at the Acid Plant
  • Plant and System Commissioning
  • Reducing Air Leaks at the SO2 Blowers
  • VFD on the O2 Compressor Motor
  • VFDs on End Pit Conveyor Belts
  • Slip Recovery Technology on Sag Mill Motors
  • Air-Cooled Chiller to Water-Cooled Chiller
  • Replace 200hp cooling tower circulation pump with 150 hp
  • On Peak/Off Peak Oxygen Production
  • Compressed Air System Modification
  • Variable Speed Pumping – Hayden to Ray
  • VFDs on Cooling Tower Fans
  • Combined Heat and Power System at the SX-EW Plant
  • Starter Sheet to Permanent Cathode Technology
  • Replace Standard Efficiency Motors with Premium Efficiency Motors

The Energy Conservation Measures selected for implementation by Lincus’ analysis show an annual energy cost savings of more than $4.0 million at both facilities, an 11% reduction in overall energy costs. The implementation cost for all of the recommended measures was estimated at approximately $16.8 million. The result of this study also indicated a payback of 4.0 and 4.2 years respectively.