Debswana undertakes advanced diamonds extracting technology

01 Jul 2019

BY PORTIA NKANI

As global demand increases for resources such as diamonds locked deep within the earth, the mining industry is being forced to adopt processes and technologies that streamline every step of the process.

Since the industrial revolution of the mid-1800s, processes and technologies across every sector of the modern economy have developed at a rapid pace.

Local diamond mining company - Debswana MINING Company is reported to have joined the fray and investigating the use of X-ray Transmission (XRT) technology for large diamond recovery prior crushing.

A pilot plant testing is reported to be on-going at one of its mines – Jwaneng.

The technology measures ore's atomic density to identify diamonds early, allowing recoveries of larger stones, while traditional  mining requires multiple crushing and concentration stages.

Agatha Sejoe - Debswana’s Corporate Affairs Manager – External Communication this week confirmed that “XRT technology is also being investigated for other size factions (middlings and fines) through research and development work.”    

Some of Botswana’s junior miners, such as Lucara Diamond also began using the XRT in 2015 and has enabled the company to record diamond recoveries last year (2018), including 33 stones over 100 carats.

Meanwhile, at Debswana Sejoe said the focus is on efficiency improvements in the mining value chain to improve productivity, as well as to enhance safety in its operation.

She added, “We have collision avoidance systems on our mining equipment to reduce metal –to-metal incidents. We are in the process of implementing a fatigue management system in order to enhance further the safety of our employees.”

In terms of processing, currently Run of Mine ore is extracted from the pit and sent to the plant for processing.

Debswana has been using the process since the commissioning of the treatment plants in 1970s at Orapa and 1980s at Jwaneng.

The first stage of the process at the plant is to crush the ore to reduce it to a manageable size for subsequent processing through the plant. Further crushing is done to economically liberate (release/unlock/free) diamonds from the host rock. The gap of the crushers is important to maximize diamond liberation and also minimize chances of breaking free large diamonds into smaller sizes. Further processing involves washing and screening into the right sizes before separation of material according to density at the Dense Medium Separation plant. High density material (diamond concentrate) is then sent to the Final Recovery plant where diamonds are recovered using X-Ray technology.    

The company said it has over the years recovered exceptional stones from their model based on colour, carat, quality and size and continue to be recovered. It however was not in a position to share the caratage and value of the exceptional stones with this publication.

According to Sejoe, the outlook for the company for the second half of the year looks positive on overall performance including safety, production performance and efficiencies.