Aproject team with mine planning as its core business is best positioned to deliver appropriate, integrated, optimum and executable mine designs, says mining consultancy Ukwazi.

Ukwazi is the largest-capacity mining engineering-focused consulting services provider in Africa and has successfully delivered mine design-related services over the last ten years as a strategic partner and independent adviser to its clients.

“Mine design is about more than the application of expensive software, with some products claiming to have all the solutions,” says Ukwazi director and principal mining engineer Jaco Lotheringen, who adds that, as a focused mining engineering outfit, Ukwazi has the experience to know what products to use for specific purposes, and how to interpret the subsequent results.

In openpit mine planning, the company mostly uses software developer Dassault Systèmes’ GEOVIA Whittle for pit optimisation, GEOVIA Surpac for block modelling and design and software provider RungePincockMinarco products for scheduling, equipment selection and haul simulation.

Mine Configuration Design
“In the world of mine planning, mine configuration and design is a major component for the successful delivery of a mining project,” says Lotheringen. He adds, that in addition to pit design and scheduling, and equipment and cost estimates based on the physical conditions of the orebody, the improved use of infrastructure, keeping the market in mind, acts as a binding element.

Lotheringen says, based on most of the currently available orebodies, the combined effect of all material-modifying factors has to be aligned on a predesign basis for projects to work in the forseeable future.

Modifying factors are not just factors such as losses and dilutions applied to openpit or strip-mine schedules, but are mutually dependent and should be aligned throughout the mining project value chain.

“This not only applies to mining-related modifying factors, but also to those that are not directly related to mining,” he says. The plant design envelope and products delivered in bulk commodity projects are not necessarily the best approach for a seemingly similar orebody and a design approach that worked in the past is not guarenteed to work in the existing market.

Lotheringen emphasises that the project team must demonstrate what the mine should look like, as well as what and how the mine delivers based on physical conditions, processing options and market-related requirements. If appropriately modelled by experienced mining engineers and competent persons, the greater project team in terms of infrastructure and plant development is able to deliver suitable solutions for the project at hand. Lotheringen maintains that it sometimes requires greater effort to determine what to design than to conduct the design and schedule itself.

Mine Planning
By revisiting the ultimate pit selection and pushback approach in openpit mines, and boxcut and ramp placement in opencast strip mines, material value and flexibility can be added, while improving the mine’s ability to execute in line with the plan.

Pragmatic schedules to match the plant design envelope or defined selectivity and stockpiling can greatly enhance project value and reduce risk. Volumes moved, cutoff grade approach and the targeting of appropriate products can also add value. Lotheringen maintains that real value cannot be added by cutting modifying factors, as it merely adds to the investor’s risk and compromises public reporting compliance.

Benefits of the Pit
Some of the challenges to staying competitive encountered by existing openpit operations include inappropriate mine configuration design, when a mine plan is insufficiently aligned with the infrastructure spend. Another challenge is when the pit does not deliver according to its potential, owing to strategic mine planning issues, or underdelivers owing to operational constraints.

An experienced and technical mining engineering team can identify shortcomings and recommend appropriate and proven solutions that can be implemented.

“For example, to increase the mining production rate, it is normally not enough to just throw additional equipment at the problem,” says the company.

Further, the physical pit characteristics, mining face length, pit-room management and pushback selection could add material value and should receive attention during all levels of study. “The risk of a mine plan, notwithstanding external review, will compromise funding and inappropriate infrastructure investment, owing to underdelivery, which is just too great a risk,” says Lotheringen.

Other identifiers for successfully operating openpit and opencast mines are experienced and appropriately sized short- and medium-term planning departments that make a material difference to the sustained delivery of specified products at the planned unit cost and volume.

Ukwazi is currently on site at various operations as part of the owner’s team to deliver these types of short- to medium-term plans.