Equipment Specs
Content
Languages

Morenci Copper Mine

From RitchieWiki

Projects > Mines
Morenci Copper Mine - Metcalf section
The Morenci Copper Mine is one of the largest open-pit copper mines in the world. Located in the state of Arizona, 9.9 miles (16 km) south of Silver City, Arizona, the mine first opened for operation in 1872 and has since closed and reopened, where it is presently being worked in different stages. The Morenci is the largest producer of copper in North America.

Morenci Copper Mine is owned by Freeport-McMoRan, one of the world's largest producers of copper, gold & molybdenum, as well as a leading manufacturer of copper strip, cadmium copper, copper wire and bars. Over 380,000 tons of copper is produced per year in this large-scale open-pit mine which marked its beginnings as an underground mine.

The mine employs approximately 2,000 people to operate heavy equipment such as drills, Caterpillar trucks, copper recovery equipment, crushing equipment, and processing equipment.

Contents

[edit] Construction History

Copper was first discovered in Morenci by a regiment of California Volunteer in 1865. What was detected turned out to be a major source of copper that reached across an entire mountain. Seven years later, mining of the underground portion of the Morenci Mine commenced, and continued until the 1930s. In approximately 1937, the operation was converted into an open-pit mine. In the conversion, the open-pit mine was made operational with rail haulage.

The mine was purchased by Copper Queen Consolidated Mining, which changed its name to Phelps Dodge in 1917. More than 90 years later, Phelps Dodge engaged in a merger agreement with Freeport McMoran Copper & Gold in an agreed takeover.

Today the pit is mined in three parts: the Metcalf, which is the original Morenci pit; the NWX, a northwest extension; and the Coronado. The three pits measure 1.5 by 1.4 miles (2.5 by 2.2 km) in total.

Morenci Copper Mine - Coronado section
The pit is mined with a number of Bucyrus blasthole drills, electric rotary rigs and a P&H 3100 and 2800 series electric rope shovels that strip the overburden that is then loaded and transported. More than 60 Caterpillar units are incorporated into the project’s daily operations, a 793 and a 797 model, with the capacity of 218 tons and 272 tons, respectively. When the pit needs to be filled, waste is used and the valuable ore is hauled to an in-pit primary crusher that grinds down the ore to the desired size.

The primary crusher has the capacity to crush 63,500 tons of ore per day. After the initial crushing stage is complete, the copper undergoes secondary crushing where it is loaded on a conveyor system and shipped to the Stargo dump-leaching site. The ore is separated into two groups by Racho mobile stacking units and the leaching of the ore takes place.[1]

Processing the ore that is received from the Morenci and Metcalf involves utilizing conventional concentrators provided by the Phelps Dodge private smelter system, which was operational until 1984. Afterwards, the ore began being processed at other Phelp smelters. The ore undergoes hydrometallurgical processing at two mills, which involves two leaching and solvent and extraction operations, as well as one electrowinning tankhouse. The MFL conversion was expanded, yielding 365,000 tons per year of cathode copper, an expansion that led to closing the Metcalf concentrator. The Morenci Mine was subsequently closed in 1989 and open only for maintenance.

In 2005, discussion began between Sumitomo and Phelps Dodge about reopening the mine for production. In October, they reached an agreement to restart the copper concentrator and construction of a copper concentrate leaching facility. The US$210 million for this project was expected to bring in 70,000 tons of electrolytic copper from the newly built facilities. The facilities were the first to contain a commercial copper concentrate leaching facility.[2]

The pit opened once again in 2006 and mined 247 metric tons of ore, milling 4.1 metric tons, grading 0.56 percent copper, and placing 230.70 metric tons of ore onto leach pads, from which 14,993 tons of concentrate copper was recovered.[3]

[edit] Equipment Used

[edit] Unique Facts

  • In October 2003, the Morenci Mine caught fire by kerosene. The fire was contained the same evening and the miners did not suffer any serious injury.[4]

[edit] Additional Photos

Morenci Copper Mine - Coronado section
Morenci Copper Mine - Coronado section
Morenci Copper Mine - Coronado section
Morenci Copper Mine - Coronado section
Morenci Copper Mine - Coronado section

[edit] References

  1. Morenci Copper Mine, Arizona, USA. Mining-Technology.com, 2008-09-25.
  2. Sumitomo Metal Mining, Sumitomo Corp. and Phelps Dodge Restart Copper Concentrator and Construct Copper Concentrate Leaching Facility at Morenci Mine. Japan's Corporate News, October, 2005. (accessed: 2008-09-25)
  3. Morenci Copper Mine, Arizona, USA. Mining-Technology.com, 2008-09-25.
  4. Kamin, John; Mares, Walter. Kerosene fire erupts at Morenci copper mine. Eastern Arizona Courier, October, 2003. (accessed: 2008-09-25)