CDE’S SAND WASHING TECHNOLOGY USED TO GREAT EFFECT LOCALLY

South African construction materials producer Ground Breakers is using UK-based CDE’s Combo all-in-one wet processing and water recycling system to enhance the quality of its products, while lowering operating costs and ensuring greater return on investment.

The Combo has been in use at Ground Breaker’s quarry in Lindley, Gauteng, for a few months, and has already garnered positive results, and serves as a successful case study for other suppliers to emulate.

At a site visit to the quarry on 1 August, Ground Breakers owner Johan Meintjes emphasised that far from the company wanting to have the monopoly on the product in South Africa, it was encouraging other suppliers to also pursue such technology, as it would raise the quality of construction materials available to the market.

CDE already has three Combo plants in the country.

Ground Breakers began producing construction materials at the Lindley quarry in November 2016 using a bucket wheel to transform the quarry’s raw feed of decomposed granite into construction sand and aggregates. The Combo is an upgrade of this system. Ground Breakers sought to replace the bucket and wheel to counteract the loss of valuable materials to ponds and excess moisture in the final products.

The quarry site had limited water sources and space to put up a proper wash plant. Moreover, any silt dams took away valuable mining area.

Ground Breakers also lost a lot of fines to the settling ponds, wasting material that it could not sell without dredging the ponds and reprocessing it through the bucket wheel.

After considering the site’s footprint and Ground Breakers’ requirements, CDE presented the Combo as the ideal solution.

Combo has a capacity range of 50 t to 500 t and boasts a modular design to combine feeding, grading, washing, water recycling and stockpiling onto one compact chassis.

The Combo allows Ground Breakers to produce two high-quality sands simultaneously from the raw feed, including plaster sand and river sand, for a much faster ROI.

Previously, Ground Breakers had been producing only one sand product, therefore, the technology has also expanded its product offering, Meintjes indicated.

The Combo’s high-frequency dewatering screen dewaters the material in one pass, removing the need for re-processing and double handling.

Once the sand slurry with the silt material is discharged from the hydrocyclones, it is delivered to the screen, which is sized according to the customers’ specific capacity requirements.

This enables Ground Breakers to provide a product above the two sand types mentioned earlier.

The Combo has advanced water management which ensures that the final products are dewatered to an average 12% moisture, making them ready for market straight from the belts.

As an added benefit, the fully integrated CDE AquaCycle thickener allows for up to 90% of the process water to be recycled directly into the system for near independence from freshwater supplies.

The more advanced Combo technology addresses the shortcomings of the bucket and wheel system, such as the difficulty to control the volumes of water required for accurate material classification, owing to the limited capacity at the feed point.

It will also engender considerable cost savings for Ground Breakers, as generally, it sells per tonne.

Her Majesty’s Trade Commissioner for Africa at the UK Department for International Trade Emma Wade-Smith, OBE lauded the partnership between Ground Breakers and CDE.

She noted that it was encouraging to see CDE expanding its footprint into Africa and supporting producers with innovative technologies.

Tthis would allow South African producers to be aligned with the latest technologies – even if the construction industry was not ideal at present, it would have quality products once demand picked up, would be ready to serve capacity, and moreover, could export products to other countries where there was demand. https://www.engineeringnews.co.za/article/uk-sand-washing-technology-used-to-great-effect-in-south-africa-2019-08-02