Energy Efficiency Survey Asarco, Hayden and Ray Mines, AZ


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.


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.