Что фактически перемещается
Sulfide copper has to be smelted, and more than half the world's smelting capacity is on the other side of the Pacific. So Chilean concentrate — about 30% copper and 70% something else — sails 19,000 km to be turned into metal, and the by-products in it become somebody else's gold, silver and tellurium.
- Материал
- Copper
- Разновидность
- Chalcopyrite concentrate from a porphyry, roughly 0.5% Cu ore grade
- Начальная точка
- Chile — Escondida, 3,100 m up in the Atacama
Шаг за шагом, граница за границей
Chile · Escondida, Antofagasta хранится у BHP as operator, with Rio Tinto and JECO (Горнодобывающая компания)
Moving a mountain for half a percent
Drilled, blasted and hauled from an open pit. At about 0.5% copper, 995 kg of every tonne is waste before processing even begins.
Почему именно здесь: A porphyry orebody, and desalinated seawater pumped 180 km uphill to process it.
Chile · Concentrator хранится у BHP (Горнодобывающая компания)
Grinding and floating
Ground to a powder and floated: air bubbles carry the sulfide minerals to the surface while the rock sinks. The result is a concentrate of about 30% copper.
Что произошло с остатком: 984 tonnes to the tailings dam. Grinding is the largest single electricity consumer on any copper mine.
Почему именно здесь: Always at the mine. Shipping 1,000 tonnes to recover 5 would be indefensible.
China · Antofagasta to Chinese smelter ports хранится у Traders and smelters (Трейдер)
Down to the coast and across the Pacific
Concentrate moves by truck or slurry pipeline to the port, then in the hold of a bulk carrier. Treatment charges — what the smelter is paid to process it — are negotiated annually and are one of the industry's most watched numbers.
Почему именно здесь: Because the smelters are there. Chile smelts a minority of its own concentrate.
China · Guixi, Jiangxi хранится у Smelter (Рафинировщик)
Smelting
Melted with oxygen. Iron and sulfur oxidise away; the sulfur is captured as sulfuric acid rather than released. What is left is blister copper at about 98%.
Что произошло с остатком: The captured sulfur becomes sulfuric acid — often sold onward to leach nickel or phosphate somewhere else entirely.
Почему именно здесь: Smelting needs scale, an acid plant, an acid market and a permit. China assembled all four.
China · Tankhouse хранится у Refiner (Рафинировщик)
Electrorefining, and the slime at the bottom
Blister is cast into anodes and dissolved electrolytically over about two weeks; pure copper plates onto cathodes. Gold, silver, selenium, tellurium and platinum-group metals do not dissolve and settle as anode slime.
Что произошло с остатком: That anode slime is where a large share of the world's tellurium and selenium comes from. The by-products of this step are a whole industry.
Почему именно здесь: Refining follows smelting; the two are almost always on the same site.
China · Rod mill and cable plants хранится у Cable and equipment makers (Производитель)
Rod, wire, and a grid
Cathode is melted and drawn into rod, then wire, then cable. 4.6 tonnes is roughly the copper in one large wind turbine, or a few hundred metres of subsea export cable.
Почему именно здесь: Copper is one of the few materials here that can be recycled endlessly without losing quality. This tonne will outlive the mine.
Это разработанный пример. Он прослеживает заявленное исходное количество материала через типовые опубликованные выходы и коэффициенты извлечения, поэтому соотношения поддаются проверке; это не запись о конкретной отгрузке. Данные о маршруте — какие страны, какие процессы и почему материал не может быть переработан в другом месте — собраны из общедоступных источников.