A compact and containerized rock treatment unit using high intensity microwaves is available for installation into existing and new process circuits for the enhancement of mining processing.
The processing of metal ores in mining can be enhanced by injecting focused and highly energetic beams of microwaves into broken rock to crack it to expose the valuable minerals making recovery faster and cheaper. Using applicator technology originally designed for a mobile microwave preconditioning robot, OffWorld has developed a conveyor-based rock processing unit built into a shipping container enclosure as a product to be installed at a mine.
Solid-State Microwave Generation...
as part of the revolution in power electronics semiconductors, the latest generation of Gallium Nitride (GaN) components allow microwaves to be produced precisely.
This allows for cheaper and faster excavation that also improves all the later processing steps required to extract the valuable metals from the rock.
Decades of research around the world in the application of microwaves into materials have enabled the introduction of a working microwave applicator system to pre-condition rock making it easier to break.
As part of its Directed Energy program pursing high tech tools for small form factor swarms of mining robots, OffWorld began a development project in 2017 to create a highly portable microwave “gun” to fire a small but intense beam of energy into a large solid mass of rock. The intent was to install this onto a mobile robot that would be able to treat a rock face with microwave energy to pre-condition and weaken the surface so that it can be excavated using small and lower force tools but also purposefully increasing the excavation rate of these tools to make them more productive.
In 2020, this technology development was accelerated with the deployment of a 100 kW microwave robot applicator system 1 km deep underground in an operating mine. This system was operated for five months underground proving that an industrial microwave system could be integrated and operated in the harsh conditions of a mine environment. The device was designed to trial preconditioning a rockface in advance of a rock cutting machine. In applying the microwave energy to a cut rock face, reductions in strength of at least 30% were achieved.
This was a very successful test campaign which set the stage for significant investment in subsequent mine trials.
UPGRADED FOR DEPLOYMENT
The system was repackaged and upgraded in 2021 for deployment.
It was deployed into a surface mine where it operated for more than one year on a variety of different rock types. Again, meaningful weakening was measured which pointed to the ability to enhance the production rate of existing rock cutting tools and which may enable other types of tools to be used productively on significantly harder rocks.
INTEGRATION OF MICROWAVES
Extensive work has been done looking at the integration of microwaves in various machines and techniques.
These include Tunnel Boring Machines, underground rock cutting machines, and for improving conventional Drill and Blast techniques. OffWorld maintains a number of solutions for these various machines, all of which can be used creatively for other existing and new machine designs. Prospective applications can be investigated with a client.
Microwave generator technology has also been rapidly improving. OffWorld has been at the forefront of driving industrial improvements in the use of phased array and solid-state technologies, and the pursuit of highly compact generator and power conditioning designs suitable for mobile applications.
A lot of this is proprietary. If you have an application, we have most likely thought of a solution.
IMMEDIATE INDUSTRY VALUE
With an eye on the rapid deployment of solution to bring value into the mining industry, we integrated an applicator into a conveyor system.
OffWorld has just integrated their patented high intensity applicator device into a conveyor system to demonstrate a modular microwave treatment system to precondition pre-crushed rock so that all subsequent crushing, grinding, and liberation can be improved meaningfully: lowering both costs and the overall energy consumed to mine and process future minerals.
RAPIDLY IMPROVING TECHNOLOGY
Microwave generator technology has also been rapidly improving.
The passage of a conveyored stream of broken rock through a very high energy density field of microwaves creates a thermal shock which is enhanced when different minerals are embedded in the same rock. Large rock structures and pieces of broken rock accumulate damage at the microscale through the formation of grain sized cracks that can turn very hard rock into soft rock.
NOVEL AND PATENTED SYSTEM
OffWorld has applied their patented applicator system.
This system can create a stable injection of this microwave energy into rock under a range of conditions, allowing for the rapid treatment of the material. As more energy is applied faster, the more efficient the process becomes.