Tag Archives: DELKOR

Ukraine iron ore miner cuts electricity consumption, process water use with DELKOR thickeners

As part of its modernisation drive, a mining and processing plant recently installed 3 x 62 m diameter DELKOR high-rate thickeners with a view to reducing electricity consumption by one and a half times for the pumping of tails, as well as rationalising the use of process water.

The project concerns the design, engineering and supply of three DELKOR 62 m high-rate thickeners for the dewatering of iron ore tailings as part of the processing plant’s modernised slurry thickening complex.

This modern complex, of which construction was completed in 2020, has now done away with outdated slurry pump stations, adopting, instead, the efficient process of thickening, hydraulic transport and storage of slurries.

Employing DELKOR’s latest generation feedwell design that comes with improved flocculation together with improved flocculant and slurry kinetics, these elevated thickeners boast large feedwells, which rank as some of the largest ever built, DELKOR says.

Ramesh Mahadevan, Regional Managing Director – DELKOR, had this to say upon successful commissioning of the thickeners: “This project is a very important reference for us in Ukraine. Given current global conditions, working with a new end user is a noteworthy achievement and one for which our entire DELKOR team must be commended.”

TAKRAF, the owner of DELKOR, meanwhile, says there has been strong demand for DELKOR technology in Latin America, noting a recent order for TAKRAF Peru for the supply of 2 x 38 m paste tailings thickeners with a capacity of 455-623 t/h.

The order, placed by a Peruvian entity processing tailings from a nearby iron ore mine, forms part of an expansion to develop a second plant. This will enable the entity to handle more tailings from the mine, according to TAKRAF.

Design requirements for the thickeners include accommodating the process demands for a paste application with a target of 65% +/- 3% solids content for the underflow. This required an equipment configuration that allowed it to operate under an expected yield stress of 200 Pa in the underflow material, the company noted.

Evolution Mining studying open-pit, underground expansion options at Cowal

Evolution Mining says it is embarking on a prefeasibility study to further expand its Cowal open-pit mine as part of a plan to build towards 350,000 oz/y of sustainable, reliable, low-cost gold production from the New South Wales operation.

Currently on the E42 stage H cutback, Evolution said during a recent site visit that there is potential to further the life of the open pit by accessing feed from the E41 and E46 satellite pits. The study looking into a possible expansion is due later this year, with the company saying it could provide long-term base load ore feed for the operation.

The mine produced 262,000 ounces in Evolution’s 2020 financial year.

The Stage H cutback the company is currently pursuing is expected to see increased ore volumes and grade mined in the first six months of this year, with the strip ratio to fall below 1:1 in its 2023 financial year, Evolution said. It also says an equipment strategy review is underway, with opportunities to “rationalise fleet” with reduced re-handling.

The haulage and loading fleet at Cowal currently consists of 20 Cat 789C dump trucks, three Cat 785C trucks, four excavators (one Liebherr 9400, one Liebherr 994B, one Liebherr 9200 and one Hitachi EX1200), plus three Cat 992G wheel loaders. It also has six hired Epiroc SmartROC surface drills at the operation, one Drill Rigs Australia GC600 drill rig, five Cat D10T tracked dozers and one Cat 834H wheel dozer.

The open-pit expansion is only part of the expansion story at Cowal, with a feasibility study underway on an underground operation. This is factoring in 3 Moz of resources and 1 Moz of reserves, with high-grade orebodies open at depth, the company says.

A second decline (Galway) is due to be developed at Cowal this year, with diamond drilling set to commence next month. The 14,300 m of planned drilling will, the company says, help confirm optimal grade control parameters and convert resources to reserves.

Evolution Mining also has a permit to increase processing capacity at Cowal to 9.8 Mt/y, with near-term incremental improvements targeting a circa-9 Mt/y rate.

The process flowsheet at Cowal includes primary crushing with a Metso Outotec 54-75 Superior MK-II gyratory, grinding with an FLSmidth 36 ft (11 m) x 20.5 ft (6.2 m) SAG mill and FLSmidth 22 ft x 36.5 ft ball mill, and screening with Schenck and Delkor screens. Sandvik H6800 hydroconecone crushers, Metso Outotec flotation cells, a Metso Outotec Vertimill, and Metso Outotec stirred media detritors also feature.

Evolution also said it is testing technology that uses glycine and cyanide during the cyanidation process of gold ore at Cowal for potential significant cost savings and environmental benefits.

Lab trials with the GlyCat™ technology from Australia-based Mining and Process Solutions have been completed successfully, it said, with the next phase being pilot plant trials to assess variability tests and long-term environmental impacts.

Tenova TAKRAF proves dry stack tailings credentials at Uzbekistan gold mine

Tenova TAKRAF says it recently installed three DELKOR overhead filter presses at a gold mine’s processing plant in Uzbekistan as part of its wider tailings dewatering system.

The system comprises three DELKOR overhead filter presses each processing around 120 m3/h of gold tailings. Each machine contains 177 mixed membrane filter plates with a size of 2 m x 2 m, and includes a high-pressure cloth washing system.

These filter presses form an important part of Tenova TAKRAF’s complete Dry Stack Tailings (DST) technologies solution, which covers processes from sedimentation to filtration and material handling, the company said.

The supply also included several pieces of ancillary equipment, including belt conveyors for cakes discharged from the filter press (each machine is equipped with a cake breaker), pumping skids for membrane inflation, filter cake washing pumps and high-pressure cloth washing pumps.

“The entire scope of supply, including the slurry feed pumps, is fully controlled and managed by state-of-the-art software,” the company said.

It added: “The complexity of the dewatering process required by this project clearly highlights DELKOR’s filter press potential across the dewatering spectrum. In fact, the filter press cycle includes filter cake squeezing, filter cake washing and filter cake air blowing, with the filter cakes washed with process water in order to remove unwanted residual cyanides from the dewatered cakes.

“Importantly, the required residual moisture content within the dewatered cakes was achieved immediately during start-up.”

Marco Zeni, Tenova DELKOR Project Manager, said: “Notwithstanding demanding site conditions, installation and commissioning, together with the required operational training, was successfully completed. With this project, we take another important step towards firmly establishing DELKOR also as a provider of filter presses to round up the filtration product portfolio and once again demonstrating that: it pays to talk to a specialist.”

Tenova DELKOR shows off sedimentation specialism at Morocco silver project

Tenova DELKOR says it has successfully supplied and carried out mechanical completion of seven DELKOR thickeners, together with its flocculation system and a DELKOR Pinned Bed Clarifier (PBC) for a silver leaching plant project in Morocco.

The thickeners are to be employed in the counter current decantation circuit of the plant, with the project including the design, fabrication and supply of thickeners, flocculation plant and PBC, supervision of installation and performance guarantee.

The PBC is a unique process for hydrometallurgical plants where solution clarity is important, according to the company. “A technology for polishing feed solutions for solvent-extraction plants, the unit offers low suspended solids counts in overflows, regularly achieving clarities of less than 50 ppm solids, and as low as 20 ppm.”

Benefits of the PBC technology, according to Tenova DELKOR, include low capital expenditure for comparative clarifying technology; no moving parts, virtually eliminating the need for maintenance; robust and stable performance; it is optimised to minimise flocculant consumption, and; a small footprint.

Ramesh Mahadevan, DELKOR India Managing Director, said: “As the industry specialist in sedimentation, DELKOR offers a range of thickeners and clarifiers catering to various applications across the minerals, chemical, industrial and water management industries with designs of up to 100 m in diameter.

“Successful hand over of this important project only serves to strengthen our capabilities in the North African region and is a true testament that.”

TAKRAF to focus on HPGR, technical studies and data collection at Bauma

Tenova TAKRAF says the company’s high pressure grinding roll (HPGR) technology, among other developments, will be highlighted at the upcoming Bauma fair in Munich, Germany, on April 8-14.

The company said, for the first time, show visitors will be able to have a complete overview of the company’s entire service portfolio, which ranges from project development services to technical studies on comminution and minerals processing, innovative fabrication solutions, various technical services and comprehensive after-sales support.

“With a view to further developing their capabilities within the market of the comminution industry, TAKRAF continues to develop their range of roller presses, with a scale model of a HPGR on display at the booth (pictured),” the company said.

Two of these machines are being manufactured at the company’s specialised fabrication facility in Lauchhammer, Germany. These machines can each handle more than 907 t/h of cement clinker, with each machine incorporating rolls with a diameter of 1,800 mm and a weight of more than 450 t per roller.

“In order to meet the challenging longevity requirements of such a machine, each roll surface is protected from wear by weld hardfacing for cement applications, and with tungsten carbide inserts for ore processing,” TAKRAF said.

The company continued: “With the integration of the well-known DELKOR and Tenova Advanced Technologies (formerly Bateman Advanced Technologies) brand of products into TAKRAF as specialised product lines, the company’s portfolio for the minerals processing and beneficiation sectors has been considerably enhanced.”

At Bauma, visitors will be able to focus upon the company’s capabilities in minerals processing, including solvent extraction and lithium recovery; as well as flotation, thickening, filtration and dry stack tailings, according to TAKRAF.

The company will also use the event to highlight its Mining Technology Centre, TAKRAF said.

“Technical studies, which compare the techno-economic aspects of different system or equipment layouts are an intrinsic part of every investment process. The quality of the study strongly depends on the experience of the study team and the level of customer involvement,” the company said.

“Based upon a common understanding of the weighting of all such decision criteria, the transfer of technical and operational experience and expertise, even beyond their own portfolio, is a key driver in enabling the customer to make a competent decision regarding the optimal solution for the specific conditions of their particular mine.

“More and more customers appreciate the added value provided by the studies as part of the engineering service portfolio, and for this reason, the company has decided to restructure and tailor their services even better in order to best meet customer requirements.

“TAKRAF’s Mining Technology Centre will be present and on hand to present the myriad of possibilities and benefits of innovative study approaches to demonstrate they are pursuing this strategy together with their customers.”

TAKRAF said, in order to provide additional benefits and services to the company’s customers based on new digital technologies, several R&D projects in the field of the industrial internet of things have also been advanced.

“In an attempt to find the most suitable technology, which results in the greatest possible benefit for the customer, first pilot machines were equipped with remote data collection and evaluation systems.

“Utilising a combination of edge computing and a proprietary azure-based platform established by Tenova, TAKRAF is able to develop applications that provide valuable insights of the company’s machines through modern and intuitive interfaces across any remote location.

“First results evince that this information can greatly assist in reducing downtime by identifying problems before they escalate into major issues and optimizing machine design, operation and performance.”

Implementation of more advanced analytics and machine learning strategies are currently on the company’s R&D agenda, TAKRAF said. “In addition, remote support solutions can also be offered.”

The company said: “This enables a remote experts-team to provide on-site assistance to the local commissioning or maintenance personnel using smart glasses and an appropriate software tool.

This is a great solution for reducing reaction times and as a side effect for reducing or even avoiding costs for expensive and time-consuming trips to the destination area.”

The company’s stand will be located in hall C2, stand 349 at Messe München in Munich, Germany, during the event.