SIC 3331 Primary Smelting and Refining of Copper
SIC 3331
This industry consists of companies that smelt copper from ore and refine copper by electrolytic or other processes. Those establishments engaged in rolling, drawing, or extruding copper are classified in SIC 3351: Rolling, Drawing, and Extruding of Copper.
331411
Primary Smelting and Refining of Copper
Copper has excellent properties that make it useful to many industries. As a base metal, copper is used both alone and in alloyed combinations with other metals. The electrical, communications, and construction industries use copper in many of their products. Approximately 70 percent of U.S. copper consumption is for electrical and electronic uses, according to the U.S. Geological Survey. Copper faces increasing competition, however, from other materials such as plastics and other highly engineered materials in electronics and electrical applications.
The value of industry shipments declined significantly in the late 1990s, falling from $6.1 billion to $2.4 billion between 1997 and 2000. Employment in the industry followed suit, dropping from 7,360 workers to 2,859 workers over the same time period.
Companies engaged in smelting and refining copper create products for a variety of national and international industries. End-use markets for copper and copper alloy can be categorized into five different functional uses. In 1994, 55 percent of copper products were used for electrical purposes and 25 percent of the products were used because they were corrosion resistant. Another 11 percent of copper products were used in heat transfer functions, while 8 percent went toward structural purposes. The final functional use is the aesthetic use of copper products, which accounted for only 2 percent of the total number.
The end-use markets for copper were primarily building related or industrial machinery and equipment related. For 1994, the 10 largest copper markets in the United States were: heating and plumbing, with 16 percent of the market share; building wire, 14 percent; commercial refrigeration and air conditioning and power utilities; each 8 percent; automotive electrical, telecommunications, and in-plant equipment, each 7 percent; electronics, 5 percent; and industrial valves and fittings and automotive nonelectrical, each 4 percent. The remaining 21 percent of the United States copper market was unspecified.
Copper in the United States went from the mines to the smelters. In some cases, the same company owned both, and in some cases, the mining and smelting were performed at nearby facilities. The mining and smelting companies are the producers of copper materials, while the wire rod mills, brass mills, and foundries work with copper and prepare the metal for delivery to manufacturers in various industries.
Mining companies process copper ores, most of which are retrieved from open-pit mines. These ores are refined and sometimes alloyed with other elements, such as zinc or beryllium. A primary smelting reactor such as a reverberatory furnace produces copper sulfide from concentrated ore. Some reverberatory furnaces were replaced by oxygen/flash smelting, which created less air pollution. The final step in smelting and refining work involves an electrolytic or other refining process. The resulting copper is often close to 100 percent pure.
Copper mining had origins in the Middle East, but reached its zenith in America. In the mid-eighteenth century, miners in the colonies discovered copper ores in what is now the northeastern United States. They mined these ores, but English law prohibited the establishment of smelting works in the colonies, so the ore was sent to England for smelting and refining.
After the American Revolution, miners and smelters moved to the newly created United States and began working in American mines and refineries. Copper sheathing began to be used on wooden ships as early as the 1790s. The copper protected the ships from the pressure and corrosive effects of the ocean. Great...
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