:: JK Research and Consulting Teams ‘Pop The Bubbly’ at Flotation Milestone

As the minerals industry prepares to celebrate the centenary of the industrial application of the flotation mineral separation process, the JKMRC and its tech transfer partner JKTech have reached their own milestone – a decade of successful flotation research and consulting.

Over the past 30 years, the JKMRC has been researching the flotation process with the aim of developing flotation models for flotation circuit optimisation. In recent years, a number of novel methods for measuring industrial flotation sub-processes have been developed and have been shown to be very cost effective for improving plant performance, according to JKTech Managing Director Dr Geoff Gault. These methods include site surveys, bubble surface area flux measurement, froth recovery measurement, ore floatability characterisation, entrainment measurement and residence time measurement. Dr Gault said that in the past ten years the state of the flotation ‘art’ had been significantly advanced, and attributed this to a collaborative research effort between three universities, UCT in South Africa, UQ in Australia and McGill in Canada. Major players in this consortium have been the JKMRC’s flotation research group and the technology transfer arm JKTech, both part of The University of Queensland.

One of several innovations developed in the past decade at the JKMRC is the Air Hold Up Device, pictured, being demonstrated by JKTech’s Principal Flotation Consultant Dan Alexander.

According to the JKMRC’s Mineral Processing Research Manager Dr Emmy Manlapig, the JK had looked at the flotation process in mineral processing well before 1995, but it wasn’t until then that a more comprehensive approach was taken, starting with characterising the effect of the ore and the machine separately. "Over the past ten years we appreciated first of all that we needed to split the system into the ore characteristics and the machine characteristics, and for each one there are separate measurement procedures."

Dr Manlapig said the most important ore characteristic measured is its floatability:  We have two ways of doing this, the floatability component method and the property based method."

He said ‘property’ meant the size and the shape of the particles as well as the amount of minerals and the amount of chemical reagent on the surface of the particles. "In terms of the flotation machinery or cell, flotation begins in the pulp phase, so we started with identifying bubble surface area flux as an important parameter, which led to developing hydrodynamic measurement tools - such as the Jg probe - to characterise this phase," Dr Manlapig said.

The researchers next applied their measuring and modeling know-how to examine the other important phase – the froth phase – which exists on the top of the pulp phases and carries away the valuable minerals, like gold, zinc or copper. "We also measure slurry residence time and other flotation characteristics in the machine after we develop a model of the flotation cells and the circuit," he said.

While carrying out this research, and realising the importance of capturing this knowledge in a practical way, the JKMRC started developing the JKSimFloat flotation circuit simulator.

Dr Manlapig explained that JKSimFloat is a vehicle by which you can simulate and optimise the flotation process. "When you are doing the experiments you go through a sequence of steps, and the JKSimFloat simulator formalises these steps," he said.

JKTech commercialised these findings and allowed them to be easily accessed through new measurement tools, the JKSimFloat software, and ready access to modeling and simulation experts.

JKTech Managing Director Dr Geoff Gault said that since full implementation three years ago, JKTech’s Flotation Optimisation program had enjoyed wide acceptance and adoption throughout the minerals industry. "The demand from the mining industry for this innovation was so high that there was little need for us to do anything by way of advertising or marketing," Dr Gault said.

He said that while the flotation process is celebrating its one hundred years of use this year, 2005, the process itself for many years was not well understood. "The main approach to improving the performance of the separation process was a ‘trial and error’ method applied by each mining operation differently," Dr Gault said. "Often the success of this approach was limited to the experience and expertise of the user, and even with a highly skilled operator, the process was time consuming and costly."

Dr Gault said JKTech’s flotation optimisation methodology is now the leading technology in this area globally. "Projects have been undertaken for the world’s leading mining companies across several continents."

Dr Gault said that JKTech’s role was critical in relation to the supply of expertise to address the growing shortage of professional metallurgists working around the world in the face of rising demand for such expertise and technology.

He said that JKTech would continue working towards improving its services and apply new approaches and technology developed through the JKMRC, presenting many more reasons to celebrate in the future.