Neves-Corvo mine
P0p2
The Neves - Corvo copper mine is one of the largest copper mines in Europe. The deposit is part of the Pyrite Belt of südiberischen Peninsula and was not discovered until 1977. End products are owned twenty-five and fifty -owned copper concentrate zinc concentrate.
- 3.3.1 Concept Study
- 3.4.1 Copper treatment
- 3.4.2 Zinc treatment
Geographical location
Neves Corvo is located about 100 km north of Faro, in the south of the district of Beja, between the towns Neves da Graça and A do Corvo. The mine is connected via the branch line Ramal de Neves Corvo to the Portuguese railway network.
Geology
The deposit of Neves Corvo is of the type volcanogenic massive sulphide deposits (VMS ). The deposit has Cu on safe and probable reserves of 27.7 million copper ore grading an average of 3.0%, 0.9% Zn, 0.3% Pb, 44 g / t Ag and 23.1 million tonnes. Zn zinc ore with an average grade of 7.3 %, 0.4% Cu, 1.7% Pb, 66 g / t Ag. The deposit is divided into the Lombador and the Semblana camp.
History
Copper mining was started in 1989. From 2006 until November 2008 zinc ore was processed. The zinc production rests since this was set in response to the rapid fall of the zinc prices on the world market. A resumption was planned for 2011. The zinc treatment was changed to copper ore.
Business
Owner of the mine until 2004, was the Somincor - Sociedade de Neves Corvo Mineira, SA until it was sold to EuroZinc, a subsidiary of Canadian- Swedish group Lundin Mining. Lundin holds 100 % of the shares.
Mine
The mine is accessed via a 700 m deep shaft with 5 m diameter. The Santa Barbara - shaft is connected to the 700 - m level and has a production capacity of 4.6 million tons per year. The second access is a ramp.
Mining method
The applied mining methods are Strossenbau with offset and Örterbau with offset. As an offset method backfilling or self- hardening offset is used.
Exploration program
Neves Corvo is deemed not sufficiently explored. Therefore, a total of 80,000 meters of drilling exploration program should be started in 2011. The drilling program has the objective to explore the size of the Semblanalagers and to prove further reserves in Lombadorlager.
Concept study
In order to exploit the deposit optimally, is currently performed a concept study to assess whether the copper-rich storage Semblana can be degraded before the underlying zinc and copper bearing Lombador ( " Lombador Phase II" ). This study compares different Auffahrungsvarianten, including a new shaft, ramps and conveyor mountains together. Investments for 2012 were postponed until the result of the study is present.
Preparation
There are two treatment plants: a copper processing with a capacity of 2.5 million tonnes per year and a zinc treatment, which is currently being expanded to a capacity of one million tons per year. The ores are processed by crushing, grinding and flotation, thickening and filtration. Downstream of the treatment are sludge ponds, which clarify the tailings. The rock is partly added to the offset.
Copper treatment
At present (2011 ) is mainly processed richer copper ore, which leaves spare capacity to recycle even poorer ore with rising copper prices.
Zinc treatment
A further extension of the zinc treatment to 2.5 million tonnes per year, which corresponds to an output of 150,000 tonnes of zinc concentrate per year in the top and an average of 112,000 t, was considered in the feasibility study " Lombador Phase I ", but the to completion concept study reset.
Production targets for 2011
For 2011, an annual production of 70,000 tonnes of copper concentrate and 4,500 tonnes of zinc concentrate was announced.