Tag Archives: Gerena

Open-pit mining to recommence at FQM Las Cruces copper operation

The Andalusia Government has authorised the resumption of exploitation work at the Las Cruces copper mine in Gerena, Spain, following a pit wall slide that occurred back in January, the operating subsidiary, Cobre Las Cruces (CLC), says.

In an announcement translated from Spanish to English and dated July 12, the company said it was in a position to immediately restart mining operations in the open pit, after receiving the corresponding authorisation from the Ministry of Finance, Industry and Energy of the Junta de Andalucía.

Open-pit mining at Las Cruces, owned by First Quantum Minerals through its ownership in CLC, was temporarily suspended as a result of a landslide that occurred on the northern slope of the pit on January 23.

The stoppage of the open pit has previously led First Quantum Minerals to warn investors the operation could lose around 25,000 t of copper output in 2019, followed by a further 25,000 t in 2020.

Since open-pit mining stopped, the operation has been feeding the hydrometallurgical plant with stockpiled ore to keep up throughput.

The approval to restart activity at the mine follows the company enacting its recovery and insurance plan at the open-pit site. This has seen CLC rebuild and reinforce the pit wall, as well as employ a georadar and laser scanner to scan the slopes of the mine in real time. A seismograph has also been employed to detect possible vibrations in the terrain.

Open-pit mining will resume in the eastern area of the open pit, CLC said. This is where the last phase of mining (phase 6) of the current open-pit plan is due to take place before the deposit is exhausted.

Las Cruces produced 70,738 t of copper cathode in 2018, slightly behind the 73,664 t it posted in 2017.

First Quantum Minerals reports land slippage at Cobre Las Cruces copper mine

First Quantum Minerals reports that during the early morning hours of January 23, a land slippage occurred on the slope of the northern zone of the open-pit mine in the Cobre Las Cruces mining hydrometallurgical complex, in Gerena, Spain.

The company clarified that the slippage did not cause harm to any persons nor any impact on any third-party facilities or land.

First Quantum said: “The company has immediately activated the established safety and environmental emergency procedures, evacuating the area and isolating the incident. Furthermore, the relevant administrations have been informed without delay, and the company is in constant communication with them.”

At the present time, production in the CLC hydrometallurgical plant has been temporarily suspended while investigations are being conducted, the company said.

“The company is monitoring the situation continuously and is taking all the necessary measures to resolve the incident and will provide updates as appropriate.”

The CLC operation produced 70,738 t of copper cathode in 2018, slightly behind the 73,664 t produced in 2017.

The operation uses conventional open-pit mining, based on hydraulic shovels and trucks, with drilling and blasting in the lower marls and ore zones. The project has a relatively high stripping ratio supported by the high-grade ore, according to First Quantum, and uses contract miners for all mine production.

The CLC metallurgical plant relies on an atmospheric leaching process to recover copper from the rich Las Cruces chalcocite ore. A unique feature of the plant is the use of eight OKTOP agitated reactors to dissolve the copper under conditions of high temperature and high acidity. Oxygen is also added into the reactors to complete the reaction. The feed to the leaching reactors is mined ore that has passed through three stages of crushing and a single stage of grinding.

Once leached, the liquid is separated from the ground solids to become PLS, the feed for the solvent extraction (SX) area. In the SX area, the copper is passed to an organic solution and then to the electrolyte that feeds the electrowinning cells. The electrowinning cells produce LME-grade copper cathodes.