Achievements in fine particle recovery and associated environmental benefits, representing decades of work led by University Distinguished Professor Roe-Hoan Yoon of Virginia Tech, has garnered him the 2014 Lifetime Achievement Award from the 27th International Mineral Processing Congress.

The award was announced at its meeting being held in Santiago, which is only held once every three years.

Since the 1980s, Yoon, a member of the a National Academy of Engineering, and his colleagues in Virginia Tech's College of Engineering have developed various advanced separation processes for the minerals and coal industries, including microbubble flotation, dewatering aids, hyberbaric centrifuge, and hydrophobic-hydrophilic separation (HHS).

The first three have been commercialized, and the last will soon be tested at a pilot scale, an essential step before commercialization. 

"With this new technology, with a patent pending, industry will be able to recover the ultrafine coal that has previously thought to be unrecoverable," Yoon said. This development also means less coal will be lost to the environment and help companies' finances.

The new advanced technology is becoming available at a time when the public is increasingly concerned about the environmental impacts associated with developing and accessing new energy resources, such as gas pipelines, fracking, and off-shore drilling, to name a few.

For Yoon, his life's work started after he learned in a high school chemistry class how detergents remove dirt from clothes. He was hooked on the "why factor." He took this teenager's fascination with bubbles, and in the 1980s developed the microbubble flotation process, a term he coined to advocate the use of small air bubbles to separate fine coal from mineral matter and recover the valuable energy resource better. 

He secured research funding from the U.S. Department of Energy and the Virginia Center for Innovative Technology to develop and patent the microbubble flotation process, which has been marketed commercially under the name Microcel. The coal industry regards it as one of the best technologies separating fine particles.

His primary collaborators in the 1980s remain his colleagues today. Jerry Luttrell, at one time his Ph.D. student, is now the E. Morgan Massey Professor of Mining and Minerals Engineering at Virginia Tech and a member of the National Academy of Engineering. Greg Adel is a professor and head of the Department of Mining and Minerals Engineering, and all three have sent myriads of highly-trained graduates out into the professional world. Many of them have become industry leaders.

During the last 15 years or more, Yoon and his colleagues have also been developing advanced technologies for separating water from fine coal.

"This was a missing link, and we took this on as a challenge," Yoon said. As he described it, as coal fines dispersed in water are cleaned with Microcel, or the likes, the clean coal product obviously becomes wet. Therefore, it is important to remove the water before shipping and utilization.

One of the advanced dewatering technologies developed at Virginia Tech involves the use of specialty chemicals that can be used to help reduce the moisture associated with fine coal. This technology has been licensed to Nalco, a subsidiary of Ecolab, a $12 billion company, for worldwide distribution.

To facilitate the marketing and sales of the specialty chemicals and others, Nalco opened a laboratory at Virginia Tech's Corporate Research Center and hired two of Yoon's former Ph.D. students

It appears that advanced separation technologies developed by Yoon and his colleagues at Virginia Tech will also be used in developing countries like India and China to reduce the emission of carbon dioxide, the major green house gas. Burning cleaner coal produces less greenhouse gas. 

"In developing countries, they will continue to use coal -- the cheapest energy source -- for a while. Helping them burn cleaner coal should help them in more ways than one," Yoon said.

Yoon said he "is most excited about the recent development of the hydrophobic-hydrophilic separation process."

It has been licensed to Minerals Refining Company in Richmond, Virginia, for worldwide distribution. The process has been tested successfully last year in Blacksburg. Based on the test results, MRC is in the process of building a pilot-scale demonstration plant in Lee County, Virginia.

If the tests are successful, construction of full-scale commercial plants will follow. Yoon added he "is proud of the fact that the new technology has been developed on the basis of his basic research in hydrophobic interaction."

His lifetime award lecture was titled "From Science to Design of Flotation Circuit Design."

Yoon received his Ph.D. in metallurgical engineering from McGill University and a bachelor's degree in mining engineering from Seoul National University.

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