Steinert implements testing plant in Namibia

6 years ago, the team at Navachab gold mine started to employ sensor-based ore sorting technology to upgrade the gold grade and remove useless material that would not burden the following processes and result in cost savings.

Since 2016, two STEINERT XSS-T X-ray transmission bulk sorting systems have been installed in a 200 tph production plant to upgrade the low grade stockpile material.

“What has amazed us is that the machine is very robust. We are getting a good reliability on the units and 80 – 90% running time is absolutely possible,” said Hildebrand Wilhelm, Ore Processing Manager for QKR Namibia Navachab operations. “I think it is a challenge to pursue new technologies in a very conservative mining environment. It is very important that you are confident of the people that you work with.”

“We have set up the plants such that we get about a 25% mass-pull to concentrate and we get an average of 70% gold recovery with this kind of set up – that makes sense to us. That is a profitable operation. We treat the material to the XRT machines and in general we double the grade of our input material and that is where the value is generated because then with the doubled grade the material can be profitably treated by the processes that come after that.”

Located in Namibia and onsite, John Knouwds, Steinert’s Area Sales Manager for Southern Africa, can assist miners who would like to test what sorting can do for their processes in the on-site test plant.

Knouwds believes that not only other miners, but also the environment can benefit with the possibility of complete dry beneficiation from the technology. He commented: “Preconcentration saves a lot of energy, water and thus money because one downstream equipment only processes material with valuable minerals.”

The set up at the Navachab plant will enable Steinert to continue testing for various mines and processing projects throughout Southern Africa. The Navachab plant itself will be capable of conducting feasibility or sighter tests, which are a way to analyse the sensors’ ability to classify mineralised and non-mineralised material, as well as the efficiency of a theoretical separation. The test plant will provide tangible data of improved and sustainable production expectations for investors, and improve economic insights to better determine the opportunities associated with investments.

It is a combination unit, capable of handling a throughput of between 5 tph and 100 tph with a 1 m working width. The unit includes an X-ray transmission sensor (XT) to identify atomic densities, two optical sensors – a colour sensor (C) and a laser sensor for 3D shape information (L) – and an induction sensor (I) that detects metals. The unit was developed as a response to increasingly complex requirements in material separation.

Specially developed Steinert software also allows for the design of new detection-algorithms, which can be implemented as needed to cope with new challenges.

 

Read the article online at: https://www.globalminingreview.com/handling-processing/05032021/steinert-implements-testing-plant-in-namibia/