Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Microwaves could take the grind out of the rock business

16.05.2003


The feasibility of using microwaves to extract minerals from rocks has been demonstrated by UK researchers.



This revolutionary technique could cut mining and mineral processing industry costs, and make it viable to process previously uneconomic mineral reserves. It could also help the environment by saving energy as 3 – 5% of the world’s entire electrical energy output is used for the size reduction of rocks and minerals.

The technique has been developed by engineers at the University of Nottingham, with funding from the Swindon based Engineering and Physical Sciences Research Council.


Conventional practice is to crush chunks of mined ore (containing copper or zinc, for example) and then grind them into smaller pieces using energy-hungry grinding mills. Typically, only 1% of the energy consumed in rock grinding actually results in size reduction, making the process very inefficient.

The new research has investigated the use of microwaves to weaken mineral ores prior to the grinding mill stage. It has focused on the principle that rocks are made up from many constituent minerals, some of which heat rapidly and expand when subjected to microwaves, while others do not heat and expand at all. This stress causes the rock to weaken and crack. It will then fall apart much more easily in the grinding mill.

The research team has looked at the best way to microwave different rock types. This has involved using computer simulations to calculate the timing and power of microwaving required, and then testing these calculations in a microwave cavity where the rocks are exposed to the microwaves. The team has found that some rocks need to be microwaved for less than a tenth of a second to produce the desired effect.

The work has attracted considerable interest from the mining industry and a major company plans to put it into practical application, if further tests prove successful.

The research has been led by Dr Sam Kingman of the University’s School of Chemical, Environmental and Mining Engineering. Dr Kingman says: “Grinding accounts for over half of the operating costs in a typical metal ore mine. The new technique could reduce these grinding costs by over 50%”.

Jane Reck | alfa
Further information:
http://www.epsrc.ac.uk

More articles from Process Engineering:

nachricht Design treatment of advanced metals producing better sculpting
08.03.2019 | Purdue University

nachricht Laser Processes for Multi-Functional Composites
18.02.2019 | Fraunhofer-Institut für Lasertechnik ILT

All articles from Process Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The taming of the light screw

DESY and MPSD scientists create high-order harmonics from solids with controlled polarization states, taking advantage of both crystal symmetry and attosecond electronic dynamics. The newly demonstrated technique might find intriguing applications in petahertz electronics and for spectroscopic studies of novel quantum materials.

The nonlinear process of high-order harmonic generation (HHG) in gases is one of the cornerstones of attosecond science (an attosecond is a billionth of a...

Im Focus: Magnetic micro-boats

Nano- and microtechnology are promising candidates not only for medical applications such as drug delivery but also for the creation of little robots or flexible integrated sensors. Scientists from the Max Planck Institute for Polymer Research (MPI-P) have created magnetic microparticles, with a newly developed method, that could pave the way for building micro-motors or guiding drugs in the human body to a target, like a tumor. The preparation of such structures as well as their remote-control can be regulated using magnetic fields and therefore can find application in an array of domains.

The magnetic properties of a material control how this material responds to the presence of a magnetic field. Iron oxide is the main component of rust but also...

Im Focus: Self-healing coating made of corn starch makes small scratches disappear through heat

Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.

Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...

Im Focus: Stellar cartography

The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.

A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...

Im Focus: Heading towards a tsunami of light

Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.

"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Modelica Conference with 330 visitors from 21 countries at OTH Regensburg

11.03.2019 | Event News

Selection Completed: 580 Young Scientists from 88 Countries at the Lindau Nobel Laureate Meeting

01.03.2019 | Event News

LightMAT 2019 – 3rd International Conference on Light Materials – Science and Technology

28.02.2019 | Event News

 
Latest News

Solving the efficiency of Gram-negative bacteria

22.03.2019 | Life Sciences

Bacteria bide their time when antibiotics attack

22.03.2019 | Life Sciences

Open source software helps researchers extract key insights from huge sensor datasets

22.03.2019 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>