Copper Concentrate

Introduction

Copper extraction techniques refer to the methods for obtaining copper from its ores. This conversion consists of a series of chemical, physical, and electrochemical processes. Methods have evolved and vary with country depending on the ore source, local environmental regulations, and other factors.

As in all mining operations, the ore must usually be beneficiated (concentrated). To do this, the ore is crushed then it must be roasted to convert sulfides to oxides, which are smelted to produce matte. Finally, it undergoes various refining processes, the final one being electrolysis. For economic and environmental reasons, many of the byproducts of extraction are reclaimed. Sulfur dioxide gas, for example, is captured and turned into sulfuric acid — which is then used in the extraction process.

Most copper ores contain only a small percentage of copper metal bound up within valuable ore minerals, with the remainder of the ore being unwanted rock or gangue minerals, typically silicate minerals or oxide minerals for which there is often no value. The average grade of copper ores in the 21st century is below 0.6% copper, with a proportion of economic ore minerals (including copper) being less than 2% of the total volume of the ore rock. A key objective in the metallurgical treatment of any ore is the separation of ore minerals from gangue minerals within the rock.

Copper concentrate is the first commercial product of the copper production line and is composed of approximately equal parts of copper, iron and sulfide. Concentrates are the raw material for all copper smelters, which by processing it obtain an impure form of metallic copper, anode or blister copper, which is later used to produce high purity refined copper. The production of concentrates implies the crushing and later milling of the ore down to a particle size allows releasing copper by flotation. The concentrates from different regions have approximately between 24% up to 36% of copper. Copper concentrates are then submitted to a final filtration and drying process to decrease the humidity to 8-9%.

Shipping and Logistic

When copper concentrate has been packed in properly closed drums it can be stowed on deck or below deck, and in this case, it will not be necessary to take special precautionary measures.

In order to counter possible temperature increases bagged copper concentrate (also if lined with plastic inner bags) should be stowed with internal ventilation ducts in ventilated containers. Containers with copper concentrate (in jute bags) may only be stowed in accessible locations. During the voyage temperatures in this cargo to be taken daily. If the temperature within the container is higher than outside forced ventilation is to be applied.

Stuffing possibly carried out under supervision of a cargo surveyor. This person also has to determine the moisture content. The cargo surveyor shall have to submit a survey report of which the ship must receive copy before departure. Metal surfaces contaminated with copper concentrates can be cleaned by rust cleaner (32% Phosphoric Acid).

Specification