When faced with a particularly challenging request to support a Colombian nickel-laterite mine, McLanahan was able to offer a unique solution.
According to McLanahan Mechanical Design Manager Ben Freeburn, the company was tasked with designing something unique while having to overcome the challenge of distance in a COVID world.
As a leading manufacturer of rotary equipment used by multiple mineral processors worldwide, McLanahan was well positioned to meet the requirements of this demanding project.
“We needed to draw on our experience in rotary equipment, specifically Rotary Scrubbers, Trommels, Screens and Rotary Breakers, to design a bespoke solution, said Freeburn. “There really wasn’t an alternative OEM that could offer such a unique solution as this. The tight timeframe and design specifications meant we had to select the best manufacturing locations for each of the main components."
Recently delivered and installed in the nickel laterite open-cut mine in Colombia, McLanahan’s newly designed piece of equipment is a customized Rotary Scrubber, nicknamed the “Rubbler”.
The need for this type of equipment was part of a long-term process improvement project and an upgrade to the customer’s current process flow. This new process involves feeding oversized material, that was previously going to the waste stockpile, into the McLanahan Rotary.
The Rotary Scrubber removes the outer layer of the material to extract additional nickel-rich material, which is then fed into the leaching process. This prevents valuable material entering the waste stockpile, saving the customer money.
Scrubbing for Success
The demand for reliable and quality rotary equipment is critical to increasing mineral processing efficiencies. It’s about achieving longer life from your equipment and reducing operating costs per ton of production.
This is certainly the case when it comes to maximizing the recovery of nickel laterite from the ore.
Scrubbing is a process that removes deleterious materials and coatings from minerals prior to the downstream process. McLanahan’s solution utilizes material-on-material attrition to separate the valuable product from the deleterious material. This means removing waste fractions such as dust and dirt, tough clay and soft rock from the nickel laterite.
According to Freeburn, the customer’s material recovery rates were fairly low using the previous system they had in place.
“They realized the valuable product was actually on the outer skin of the ore, which was unusual as they didn't actually want to crush and mill the ore to recover the nickel laterite or send it to their leach process. They just wanted the outer coating of the material so they could recover as much of the material as possible,” he said.
“It wasn't like scrubbers or wet processing systems where you mine the ore and it's covered in clay and dirt, and then it gets washed. This machine wasn’t doing any of that, it was dry processing without any water being introduced.”
The McLanahan team had to effectively create a customized machine that integrated the features of several other machines. This meant configuring the Rotary Scrubber from scratch by using proven technologies.
“We worked diligently with the customer’s process engineers to ensure our product was customized to their specific application,” said Freeburn.
Delivering on a Global Scale
McLanahan was able to manage the difficult process of sourcing the required parts from multiple locations around the world including Brazil, Europe, China and Australia. The tight delivery envelope necessitated a degree of site assembly. This did not lend itself to consolidating globally supplied components in a single assembly shop only to be disassembled to meet the delivery window.
“Because of the multi-location supply, we had to fast-track the verification process of all the parts. Using templates and jigs allowed us to create sub-assemblies as opposed to full assembly,” said Freeburn.
Another significant logistical challenge for McLanahan proved to be the location of the project, being in Colombia, and the subsequent impact on transport.
“The design was impacted by delivery requirements, so we had to ensure the components could fit into purpose-built containers with maximum width, height and mass limits,” Freeburn said. “We had a 25-tonne limit and a much narrower dimensional envelope for transport. We knew we had to come up with modular sub-assemblies, and ingenuous frames that allowed the customer to use as assembly jigs, ones that featured lift points for transportation in a single orientation and could then stand up for a four metre barrel.
Freeburn said the objective was to deliver a machine that was configurable to have greater operating volume for more efficiency or lower operating volume for less, depending on tests carried out during commissioning.
“In the end, the McLanahan designed Rotary Scrubber is something truly unique,” shared Freeburn. “It was a collaborative effort across our three global operations in Australia (engineering design and project management), Chile (sales and supervision) and America (installation and commissioning services).”