Australian manufacturer impressed by German screening technology

16.02.2021, Perth, Australia

In an official announcement, the Australian graphite producer BassMetals Ltd. recently announced the latest developments of the company to its shareholders. Among them were the convincing results from the RHEWUM technical center.

Currently, BassMetals Ltd. uses three screening machines for producing five different (graphite) products. This procedure is very time-consuming and is to be simplified in the future by producing all separating cuts on only one machine. The company commissioned RHEWUM GmbH to deal with this problem and to find a solution.

Whether as a pencil lead, solid lubricant, material for self-lubricating bearings and seals, or even as the shaft of a golf racket - graphite has many uses. In nature, the mineral occurs in the form of isolated flakes and grains in carbon-rich metamorphic rock and as veins in pegmatite.

The company BassMetals Ltd. owns the Graphmada Large Flake Graphite Mining Complex in eastern Madagascar, in the immediate vicinity of the country's only export port in Toamasina. From there, the mined and processed graphite is shipped primarily to the USA, Europe and India. The mining area has a unique graphite deposit in soft rock (regolith), which is characterized by a proportion of more than 90 percent large-flake graphite. Large-flake graphite occurring in soft rock can be mined cost-effectively and processed economically without the need for drilling, blasting and crushing, which preserves the large-flake graphite during the mining and processing phases. Graphite in hard rock requires more costly drilling, blasting and crushing operations, which significantly reduces the size of the graphite flakes recovered.

The challenge in screening the graphite flakes is that it is a very fine, sticky material with a rather elongated shape, which is also very light. In addition, the customer's requirement was that no product should contain more than 20 percent oversized particles. The graphite flakes are screened in four separating cuts.

For the test screening in the RHEWUM technical center, a RHEWUM screening machine type WA was used. Electromagnets achieve accelerations of 15 g and more on the screen cloth, which are necessary to overcome the adhesive forces of the fine particles. Both the requirements for high product purity and the maximum content of oversized particles of 20 percent were met in the test screening with the RHEsono^®.

In the future, the customer could replace its three screening machines with one RHEsono^® with four decks, while increasing efficiency and saving costs at the same time. According to a recent study by BassMetals Ltd., it would be possible for the company to screen and package up to 20,000 tons of graphite per year with a single RHEWUM screening machine - without any loss of product or quality.

BassMetals Ltd. is enthusiastic about the first-class screening results of the RHEsono^® and very interested in purchasing the screening machine. We at RHEWUM are particularly pleased that German screening technology from Remscheid is also convincing on the other side of the world.