Tag Archives: Doppelmayr

Doppelmayr ropeway tackles mine backfill task at Buriticá gold operation

A Doppelmayr ropeway is now up and running at the Buriticá underground gold mine in northwest Colombia, navigating mountainous terrain to transport backfill material from the bottom of the valley to the mouth of the mine.

In October 2017, Austria-based Doppelmayr was awarded the contract to build a 1.4 km long ropeway with material buckets for a transport capacity of 175 t/h. The system was conceived as a continuous bi-cable ropeway, with a fixed tensioned track rope for the material buckets with their carriage to travel on. The buckets are driven by the continuously moving haul rope loop to which they are attached via detachable grips.

The area where the mine, owned by Zijin Mining, is located is mountainous and therefore logistically challenging. The reusable residues of the gold extraction process are used as underground backfill, which is why they must be taken from the bottom of the valley to the mouth of the mine at 1,700 m above sea level, thereby covering a difference in altitude of approximately 646 m. What would be an arduous and long journey for trucks, with plenty of exhaust emissions, becomes a swift and efficient job if a material ropeway is used, Doppelmayr says.

To allow for the haul rope to be run at a constant speed, the buckets are detached from the loop in the stations and slowed down before they are loaded via a chute. Once a bucket has been filled, it is accelerated to running speed again and re-attached to the haul rope before leaving the station.

In the unloading station, the bucket is once more taken off the haul rope. At the designated unloading point a special mechanism unlocks the latch on the bucket, the bucket is tipped, and the material is safely transferred onto another chute. The bucket then returns to its original position. It is locked again and re-attached to the haul rope before travelling back into the valley empty.

In the past, continuous bi-cable ropeways have often been used for material transport applications, the company explained.

“For the Buriticá project, Doppelmayr’s engineers have revised the design and mechanics of continuous bi-cable ropeways from scratch and optimised it for the transport of material in buckets,” it said. “The system complements Doppelmayr’s portfolio of material transport solutions.”

Put into service in February 2021, the solution has a transport capacity of 175 t/h of gold residues, a running speed of 6 m/s, and comes with 20 carriers and one tower.

Kinross Gold weighs SART plant and rope conveyors for Lobo-Marte development

Kinross Gold has announced the results of a prefeasibility study for its Lobo-Marte project in Chile, which includes consideration of sulphidisation, acidification, recycling and thickening (SART) technology, as well as the use of rope conveyors.

The open-pit, heap leach operation would produce around 4.5 Moz of gold at average all-in sustaining cost of sales of $745/oz, according to the study. It would operate for 15 years, which includes 12 years of mining followed by three years of residual processing.

The initial estimated capital cost for the project is $765 million, plus around $230 million in contingency, Kinross said. The estimated capital costs includes mine equipment, crushing and storage facilities, conveyors, and site utilities and infrastructure.

The most interesting processing aspect is the use of a SART plant in the mine’s design. Kinross has previously used SART technology successfully in the region at its former-operating Maricunga mine, which BioteQ Environmental Technologies (now named BQE Water) installed.

The company also plans to use rope conveyors, such as those provided by Doppelmayr at the likes of Torex Gold’s ELG mine in Mexico.

Subject to a positive development decision, the study estimates Lobo-Marte project construction beginning in 2025, with first production expected in 2027. Production would commence after the conclusion of mining at the company’s La Coipa project (pictured), which is located some 50 km northwest of Lobo-Marte, and where the company is continuing to explore opportunities to extend mine life.

Back in February, Kinross announced it is proceeding with the La Coipa Restart project to mine the Phase 7 deposit. The La Coipa restart is expected to generate strong returns and produce a total of around 690,000 oz of gold from 2022 to 2024. The project plan includes refurbishing the existing process plant, camp and other infrastructure, as well as the mine fleet from the Maricunga operation that has recently been placed on care and maintenance.

The company plans to commence a feasibility study on Lobo-Marte later this year, with scheduled completion in the December quarter of 2021. The feasibility study is expected to provide the detailed engineering and project description required for permitting and submission of an Environmental Impact Assessment, Kinross said.

“The Lobo-Marte project provides Kinross with an excellent, organic development option that has attractive all-in sustaining costs and offers substantial upside leverage to the gold price, without increasing project cost requirements and risk,” Paul Rollinson, Kinross President and CEO, said. “The project represents a potential synergistic, long-term mine life extension in a favourable mining jurisdiction and delivers a significant 6.4 Moz addition to our current gold reserve estimates, increasing the company’s overall reserve mine life.

“As we move forward with the feasibility study for this longer-term project, we will continue to prioritise balance sheet strength and disciplined capital allocation.”

Doppelmayr overcomes backfill hurdles at UK quarry with RopeCon system

A Doppelmayr RopeCon® system is to help Aggregate Industries with an innovative backfill solution at its Bardon Hill quarry, in Leicestershire, England.

Aggregate Industries has recently developed a new quarry extension at this strategically important site, one of the UK’s oldest continuously operated quarries, extending mineral production for a further 27 years, according to Doppelmayr.

During the initial 14 years of production, over 12 Mcu.m of overburden must be progressively extracted. This will be processed and conveyed for emplacement within the existing exhausted quarry to a depth of 125 m.

A road haulage solution was not permitted due to the generation of considerable CO2 emissions, while a conventional conveyor system would have been very costly due to the length and number of transfer points required to navigate the existing quarry haul roads, according to Doppelmayr.

“An innovative and sustainable solution was therefore required to minimise the impact upon local residents, wildlife and the environment,” it said.

Other operational constraints included the requirement to minimise the drop height from material discharged into the quarry and to allow continuous operation of the delivery conveyor without compromising the use of heavy mobile equipment to handle and place the delivered overburden.

To address these complex requirements of Aggregate Industries, Austria-based Doppelmayr has developed a novel solution for the backfill system. The proven RopeCon system, a combination of ropeway technology and conventional conveying technology, will span 850 m across the entire pit with track ropes. The belt, which transports the overburden, moves on these steel wire track ropes and the material can be transferred onto a second belt directly in the rope span.

“This creates a second discharge point at a distance of approximately 100 m from the first discharge point,” Doppelmayr said. “Depending on where the material is needed, either the first or the second discharge point can be used.”

To solve the problem of the drop height, a concept has been developed that gradually reduces the sag as the backfill progresses. The drop height can thus be kept below 45 m at all times to minimise the impact from noise and dust during operation of the system, Doppelmayr said.

The contract was signed in March 2019 and the system is due to be operational in December 2020 where it will transport approximately 1,000 t/h of overburden over a distance of 500 m.

Doppelmayr opens up vertical transport options in underground mining

Doppelmayr has turned its RopeCon® system on its head, designing a new vertical material transport concept for the underground mining space called the Vertical Shaft Conveyor.

Unveiling the concept at the AIMEX 2019 event in Sydney, Australia, the company said the Vertical Shaft Conveyor “opens up new material transport options for underground mining and gives the chance to reduce the haul truck fleet and exhaust emissions”.

Doppelmayr has become synonymous with its RopeCon installations at global mine sites across the globe. These innovative continuous conveyors (pictured) can be adapted to uneven terrain, transporting material on a flat belt with corrugated side walls, elevated off the ground on tower structures. Installations include the ELG gold complex in Mexico (Torex Gold) and Booysendal South in South Africa (Northam Platinum).

The Vertical Shaft Conveyor, meanwhile, comes with a vertical lift capability of up to 750 m, a conveying capacity of 2,000 t/h, a maximum lump size of 150 mm and clear shaft diameter requirement of 3.5 m. The company pointed out these specifications are all dependent on the material specifications and operating conditions with, for example, a 700 m vertical lift application coming with a conveying capacity of 700 t/h.

System advantages the company stated included:

  • No access to shaft required – neither for installation nor operation;
  • Maintenance can be carried out in the terminals;
  • Re-use of existing ventilation shaft is possible;
  • Continuous material flow, and;
  • Heat development is reduced with the main drive installed above ground.

The company says: “Maintenance is simple and cost effective, as all moving parts are mounted to the belt and will pass the terminals at regular intervals. Ropes and shaft are inspected by a camera system which is attached to the belt.”

Like a conventional conveyor, the system can be loaded by transfer conveyor or by an ore pass, with the material transported to the surface on a conveyor belt.

“This belt is equipped with side walls and cleats, forming pockets for the material,” Doppelmayr says. Above ground, the material is transferred to another conveyor, another RopeCon installation or discharged onto a stockpile.

The company puts the vertical lift capabilities down to, among other things, the belt being turned after discharge. This sees the entire belt tension deflected via on return drum, with the entire belt width can be used as a bearing surface.

Another reason for the lift capability is the wheel sets run on guiding rails at the loading terminal, which safely guide the belt into the shaft. Ropes in the shaft always guide the belt during operation.

Doppelmayr RopeCon transporting the tonnes at Guatemala cement operation

Doppelmayr Transport Technology has come up with an innovative way to connect Cementos Progreso SA’s crusher with its new San Gabriel cement plant using RopeCon® material transport technology.

The San Gabriel cement plant is located some 35 km northwest of Guatemala City, Guatemala, where Cementos Progreso produces some 2.2 Mt/y of cement for the local market. The limestone needed for the process is mined in a quarry around 200 m lower than the cement plant, with the terrain between the crusher in the quarry and the plant being hilly and wooded and stretching over a distance of 1.58 km.

The company had been planning to build a new cement plant for some time yet, among other things, the project required an innovative solution to transport the limestone and marl from the crusher over the hilly terrain to the processing plant.

By using RopeCon to transport the limestone between the crusher and the processing plant Cementos Progreso is able to cross the terrain in a straight line despite the topographical situation. This means that a gradient of 22° is reached where the terrain is steepest.

Because the RopeCon belt is fitted with axles with running wheels at regular intervals, no additional cleats were required to tackle that gradient.

The system requires no more than four towers over its entire length and, thanks to the long rope spans between the towers, the amount of space required on the ground can be reduced to a minimum.

The need to interfere with vegetation remains limited to a small number of points and the track does not represent an insurmountable obstacle for wildlife or humans, according to Doppelmayr.

The RopeCon installation has now taken up operation. The material is loaded onto RopeCon by a feeder conveyor and unloaded at the unloading station via a housed-in chute. Some 2,100 t/h of limestone and marl is transported to cover the demand for cement production using a 1,680 kW motor operating at a speed of 3.6 m/s.

RopeCon has been developed by Austrian ropeway manufacturer Doppelmayr to offer the benefits of a belt conveyor as well as those of a cable car by “successfully combining what is best in both technologies”, according to the company.

The system is currently in use for a variety of material transport applications and consists of a cross-reinforced continuous flat belt with corrugated side walls driven and deflected by a drum in the head or tail station. The belt is fixed to axles arranged at regular intervals, which support the belt. Running wheels are fitted to either end of the axles. These run on track ropes with fixed anchoring and guide the belt.

The three track rope pairs form the line structure for the system and are elevated off the ground on tower structures. The system, therefore, requires only a minimum of space on the ground and is ideally suited for difficult terrain and to cross obstacles of all kinds.