Ingot - Slabs - Billits - Wire Rod

Copper cathode is the primary raw material input for the production of copper rod for the wire and cable industry. Copper is also used in the production of brass, copper tube, copper sheet products, and found in over 450 alloys. Copper cathodes are used as a raw material feed for the production of high purity copper and copper alloy products. It is therefore essential that, during shipping and transportation, they are not contaminated with any extraneous materials

The main difference between copper and electrolytic copper is “Purity”, where copper obtained through traditional mining and smelting processes may contain impurities, whereas copper cathodes have a higher level of purity, typically greater than 99.95%

In order to produce market-grade copper cathodes, blister copper must first be cast into anodes and treated electrolytically. Immersed in a tank of copper sulfate and Sulphuric acid, along with a pure copper cathode starter sheet, the blister copper becomes the anode in a galvanic cell

As a current is introduced, copper ions begin to migrate to the cathode, or starter sheet, forming 99.9-99.99% pure copper cathodes. Individual cathode sheets are manufactured to different dimensions by different suppliers in the range of 0,5 m2 to 1 m2 and 3 to 20 mm thick, with or without ‘ears’

Copper is found mainly in sulfide minerals and oxide minerals, which are crushed before being sent to a concentrator. The concentrate is then pumped to our smelter where flash smelting and flash converting furnaces generate copper matte and copper blister. Anodes are then cast and sent to our refinery.  At the refinery, the anodes are plated to starter sheets in an electrolytic process to produce copper cathode

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From its original home buried underground in a mine to its use in a finished product such as wire or pipe, copper passes through a number of stages. When it is recycled, it can pass through some repeatedly…

1. Mining, Crushing

The beginning for all copper is to mine sulfide and oxide ores through digging or blasting and then crushing it to walnut-sized pieces

2. Grinding

Crushed ore is ball or rod-milled in large, rotating, cylindrical machines until it becomes a powder usually containing less than 1 percent copper. Sulfide ores are moved to a concentrating stage, while oxide ores are routed to leaching tanks

3. Concentrating

Minerals are concentrated into a slurry that is about 15% copper. Waste slag is removed and Water is recycled. Tailings (left-over earth) containing copper oxide are routed to leaching tanks or are returned 

to the surrounding terrain. Once copper has been concentrated it can be turned into pure copper cathode in two different ways: Leaching & electrowinning or smelting and electrolytic refining

4a. Leaching

Oxide ore and tailings are leached by a weak acid solution, producing a weak copper sulfate solution

5a. Electrowinning (SX/EW)

The copper-laden solution is treated and transferred to an electrolytic process tank. When electrically charged, pure copper ions migrate directly from the solution to starter cathodes made from pure copper foil. Precious metals can be extracted from the solution

OR

4b. Smelting

Several stages of melting and purifying the copper content result, successively, in matte, blister and, finally, 99% pure copper. Recycled copper begins its journey to finding another use by being remelted

5b. Electrolytic Refining

Anodes cast from the nearly pure copper are immersed in an acid bath. Pure copper ions migrate electrolytically from the anodes to "starter sheets" made from pure copper foil where they deposit 

and build up into a 300-pound cathode. Gold, silver and platinum may be recovered from the used bath

6. Pure Copper Cathodes

Cathodes of 99.9% purity may be shipped as melting stock to mills or foundries. Cathodes may also 

be cast into wire rod, billets, cakes or ingots, generally, as pure copper or alloyed with other metals

7. Cathode is then converted into:

Wire Rod 

Coiled rod about 1/2" in diameter is drawn down by wire mills to make pure copper wire of all gages

Billet 

30' logs, about 8" diameter, of pure copper are sawed into these shorter lengths which are extruded 

and then drawn as tube, rod and bar stock of many varied sizes and shapes. 

Rod stock may be used for forging

Cake 

Slabs of pure copper, generally about 8" thick and up to 28' long, may be hot- and cold-rolled 

to produce plate, sheet, strip and foil

Ingot 

Bricks of pure copper may be used by mills for alloying with other metals 

or used by foundries for casting

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Bundles of cathode sheets are usually between (1 & 4 MT) and are held together by steel strapping and are shipped unpackaged 

Care should be exercised during handling to avoid straps breaking which cause the bundles to become unstable with potential separation and loss of some sheets

Electrolytic copper cathodes are usually bought upon a weight basis, and are normally shipped unpacked, often bound together with metal bands

During handling of bundled cathodes, care should be taken that rough handling does not cause breakage of metal bands

It is quite common for cathodes to have surface excrescences arising out of the process of manufacture, in the nature of small ‘pimples or warts’ 

Handling in the course of transit may result in these surface irregularities being broken down and the cathodes delivered with a smooth surface. This may result in a difference between the shipped and delivered weights

Cathodes are manufactured with ‘ears’ for hanging purposes and frequently these ‘ears’ are knocked off, resulting in further loss of weight 

If over-stowed, care should be taken that other cargo does not cause deleterious contamination of copper

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