Pueblo Viejo Archives - International Mining

Martin Engineering, a leader in bulk material handling technologies and training, has announced the availability of two rugged secondary conveyor belt cleaners, both engineered for fast and easy maintenance.

The innovative design of the DT2S and DT2H reversible cleaners from Martin Engineering reduces system downtime and labour for clean up or service, while helping to prolong the service life of other conveyor components, the company says.

The models feature a unique split-track blade cartridge that slides in and out on a stainless steel mandrel, meaning the cleaners can be serviced or replaced without stopping the belt when on-site safety approvals are in place, Martin Engineering claims.

Dave Mueller, Conveyor Products Manager for Martin Engineering, says: “Even when the cleaner is encrusted with material, one half of the split frame can be removed so the cartridge can be changed in just five minutes. This allows users to have a spare cartridge on hand and quickly change it out when the blades need replacement. Then they can take the used cartridge back to the shop, clean it up and change the blades so it’s ready for the next service.”

These secondary cleaners serve a wide variety of applications, including mining. Both products significantly reduce material carryback, and arr engineered to accommodate reversing conveyors to avoid damage to the belt or splicing, the company says. With steel blades and tungsten carbide tips set into a flexible base, the DT2 cleaners offer simple, effective solutions that can solve a number of carryback-related problems.

Martin DT2H Reversing Cleaner XHD

Designed for particularly demanding conditions, the DT2H Reversing Cleaner XHD is suited for heavy material loads on belts ranging from 400 to 2,400 mm wide that operate at speeds up to 6.1 m/s.

The company explains: “Carryback accumulations along the return run of the conveyor can occur when the cleaning systems on a conveyor fail to remove most of the material that adheres to the belt after unloading its cargo. Increased build up results in unnecessary labour costs for clean up, and can lead to premature failure of conveyor components if left unchecked.”

Mueller said: “Carryback can have an extremely sticky texture and abrasive nature, which can muck up conveyor components and contribute to premature failure. One key to the success of these cleaners is the blade’s negative rake angle (less than 90 degrees). With a negative angle, you get a ‘scraping’ action that mitigates potential belt damage, while delivering outstanding cleaning performance.”

Martin DT2S Reversing Cleaner

Like its larger counterpart, the Martin DT2S reversing cleaner can be installed on belts ranging from 400 to 4,800 mm wide. But, unlike the DT2H, the DT2S is designed for a lower maximum belt speed of 4.6m/s on belts with vulcanised splices. Mueller pointed out that this is primarily due to the difference in applications: “The DT2S has a slim frame that allows it to fit in spaces as narrow as 7 in (178 mm). As a result, the DT2S can be attached to belts that may be too small for primary cleaners.”

Both of the DT2 cleaners can be used in medium- to heavy-duty environments, providing a lasting solution to a diverse array of complex problems that are caused by carryback and minimising fugitive material, the company says.

Pueblo Viejo case study

An example of the cleaners’ performance can be found at the Pueblo Viejo Dominicana Corporation (PVDC) mine in the province of Sanchez Ramirez, about 89 km northwest of the city of Santo Domingo in the Dominican Republic. Operators at the operation, majority owned by Barrick, were experiencing excessive carryback and dust on its conveyor system, resulting in expensive equipment failures, unscheduled downtime and increased maintenance. Production is 365 d/y, but, between April and October, moisture can cause cohesion in fine clay particles, causing the cargo to become sticky. The substance had the consistency of thick toothpaste, which was also able to adhere small chunks of aggregate to the belt, causing destructive carryback that damaged pulleys and headers.

In just two weeks, Martin Engineering technicians replaced the existing belt scrapers at 16 locations with Martin QC1 Cleaner XHD primary cleaners fitted with low-adhesion urethane blades specifically designed for tacky material loads, along with DT2H secondary cleaners. The secondary cleaner blades can endure hot summer temperatures, high moisture content and constant production schedules, according to the company.

Following the upgrades, operations are now cleaner, saferand more productive, giving executives and stakeholders more confidence in the sustained operation of the mine, which is projected to be profitable for the next 25 years or more.

Barrick Gold says the Pueblo Viejo power plant is expected to receive its first natural gas in the March quarter as it looks to lower greenhouse gas emissions and cut costs, in line with the group’s clean and efficient energy strategy.

Pueblo Viejo entered into a 10-year supply agreement with AES Andrés DR, SA, in May 2018, for the provision of natural gas and the construction of a gas pipeline from the AES gas terminal to the Quisqueya I power plant for the mine. This is also expected to benefit the San Pedro region which has not previously had access to this cleaner alternative fuel, the company said.

Owned 60% by Barrick and 40% by Newmont Goldcorp, Pueblo Viejo is expected to produce 550,000-600,000 oz of gold in 2019 at all-in sustaining costs of $610-650/oz.

Barrick President and Chief Executive, Mark Bristow, says, since the commissioning of the Quisqueya I power plant, in 2013, Pueblo Viejo has looked for ways to reduce the impact of its air emissions on the environment and the cost of energy production.

“The conversion of Quisqueya I to natural gas will help reduce Pueblo Viejo’s power generation costs by some 30%. Greenhouse gases will also be cut by 30% and nitrogen oxide by 85%, and the mine’s dependence on oil will be significantly decreased,” he said.

The gas pipeline is facilitating the conversion of other power plants in the region to translate into further reduction in greenhouse emissions and significant savings in energy costs within the Dominican national grid, according to Barrick. Recently other power producers in the area have announced the conversion into natural gas of an additional 525 MW, it said.

Barrick said: “Pueblo Viejo is also contributing to the Dominican electricity sector with the construction of the Bonao III power substation as part of a public/private alliance with the Dominican Transmission Entity and Empresa Generadora de Electricidad Haina (EGE Haina) which owns the power plant Quisqueya 2 located next to Quisqueya I. The substation is expected to help to provide more stability to the country’s national grid. Finalisation is scheduled for mid-next year.”

Bristow noted: “The conversion agreement, the natural gas pipeline and the Bonao III substation represent a step forward, not only for Pueblo Viejo but for the Dominicans, as it shows not just environmental benefits, but also a significant reduction of the country’s electricity cost, less dependency on crude oil and more stability for the national power grid.”

Martin Engineering cleans up conveyor operations with DT2S, DT2H

Barrick Pueblo Viejo natural gas plant about to power up