Conceptual engineering to copper concentrate

On December 27, 2014, startup and commissioning of the Teghout Copper-Molybdenum Concentrator Plant resulted in the first concentrates produced and represents a great success story for FLSmidth’s commitment to being a One Source solution and technology provider.

This is a major milestone in the Teghout project life and a huge achievement for FLSmidth and all the people involved.
— Manfred Schaffer President, FLSmidth Minerals Division

The Teghout project is located in the Lori province of northern Armenia and is in close proximity to the borders of Georgia and Azerbaijan. It is unique in that the work started as benchscale testwork at FLSmidth’s metallurgical testing laboratories in Salt Lake City, USA and progressed into a relationship that would involve a variety of people from locations around the world who came together to provide engineering, flowsheet design, equipment and process expertise for a fully operating copper concentrator plant in Armenia.

The project originated in 2007, with FLSmidth working with Vallex Group to design the plant for an initial ore throughput rate of 7 million tonnes per annum (TPA). Expansion of a second ball mill in the grinding circuit would then bring it to over 12 million TPA. After initial consultation, Vallex started the ordering of comminution equipment for the plant in 2008, mainly the SAG and ball mills.

During the early stages of the project, the flowsheet concept being utilized by Vallex was more of a traditional, former Soviet approach to metal recovery. However, in early discussions with the client, FLSmidth process specialists recognized opportunities to streamline the flowsheet and proposed that preliminary testwork be conducted to create a more optimal and efficient solution.

A variety of small-scale tests were conducted by FLSmidth’s Dawson Laboratories in 2009 to validate an alternative flowsheet concept with an objective to process simplification, while still maintaining the customer’s process targets for metal recovery and quality.

Philip Thompson of FLSmidth’s Dawson Laboratories in Salt Lake City, USA, who's globally renowned for his mineralogical and metallurgical expertise, was instrumental in setting up the test plan and overall supervision of the testwork for the Teghout project.

Gillian Hall, FLSmidth process technical advisor on the project, stated, “This was the perfect opportunity to combine multiple facets of FLSmidth into the overall solution.”

The project design was initially conducted out of the United Kingdom. The major equipment sizing and selection, together with the plant layout, was validated by FLSmidth’s Process Technology Group with a close collaboration with various FLSmidth product companies to ensure that each stage utilized complementary equipment to ensure recoveries could be maximized.

“This is a major milestone in the Teghout project life, and a huge achievement for FLSmidth and all the people involved,” said Manfred Schaffer, President of FLSmidth’s Minerals Division. “This represents the first complete concentrator project by FLSmidth that is now in rampup.”

Designing the plant, including engineering, sizing and situating the equipment, represented a number of challenges due to the site’s location and topography; as well as changing the design from more historically set-up concentrators. Through careful analysis and teamwork, the best overall flowsheet was designed and now includes process equipment for crushing, grinding, flotation and regrind, concentrate thickening and filtration, tailings disposal by gravity, and water recovery. The flowsheet also includes a molybdenum separation plant that will be started up once the copper circuit is fully commissioned.

As the project was advanced, detail work was carried out at FLSmidth's minerals technology center in Salt Lake City, USA. This also allowed for key design input around the molybdenum plant to be undertaken, together with drawing in experience from the individual product line managers and their knowledgeable teams who reside at this location.

The overall engineering completion was accomplished in 2013 and included a 3D model of the concentrator facility. A 3D model of the flotation area is shown at the bottom of page 18 and can be compared to the photo of the actual constructed facility shown below.
Commissioning of the Teghout plant started in late September 2014, and after years of hard work and cooperation, ore was introduced into the SAG mill in mid-December. The first concentrate was produced on December 27, 2014. The concentrates were shipped to the nearby Alaverdi smelter in January 2015.

As of early April 2015, more than 1,000,000 tonnes of ore have been processed, with the initial concentrates production being approximately 20,000 tonnes at an assay over 26% Cu. This translates to more than 5,000 tonnes of copper. In the not-too-distant future, the molybdenum section of the plant will also be brought online.

Some of the challenges in the commissioning and ramp-up included what was then an inexperienced local workforce. Once again, FLSmidth personnel were able to assist with hands-on training and guidance to get workers the proper support and create a safe and stable working environment.

Hall commented, “As with many of our systems-type projects, there is a performance guarantee associated with it. The importance of FLSmidth input, process technology guidance in the commissioning, and training requirements cannot be overstated as the plant continues to ramp up to full capacity.”

CONTACT: Gillian Hall