Apparatus for the separation of hydrophobic and hydrophilic particles using microbubble column flotation together with a process and apparatus for generation of microbubbles

Patent 5397001 Issued on March 14, 1995. Estimated Expiration Date:

November 30, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

1240824

1747687

2778499

3012671

3286992

3339730

3371618

3371779

Vortex coagulation means and method for wastewater clarification
Patent #: 4031006
Issued on: 06/21/1977
Inventor: Ramirez , et al.

Flotation method and apparatus
Patent #: 4216085
Issued on: 08/05/1980
Inventor: Chittenden

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Inventors

Assignee

Virginia Polytechnic Institute and State University

Application

No. 982890 filed on 11/30/1992

US Classes:

209/170, Pneumatic209/168, Apparatus210/221.2, And gas injecting means other than by mechanical agitation261/122.1, Submerged screen366/338, Curved deflector surface366/339Helical ribbon or strand

Examiners

Primary: Lithgow, Thomas M.

Foreign Patent References

680576 CA. 02/13/1964
694547 CA. 09/13/1964
3312070 DE. 10/13/1984
3417327 DE 11/13/1985
694918 GB 07/13/2012

International Classes

B03D 001/24
B03D 001/14

Abstract

An apparatus is disclosed for the microbubble flotation separation of very fine and coarse particles, especially coal, and minerals so as to produce high purity and high recovery efficiency. This is accomplished through the use of a flotation column, microbubbles, recycling of the flotation pulp, and countercurrent wash water to gently wash the froth. Also disclosed are unique processes and apparatus for generating microbubbles for flotation in a highly efficient and inexpensive manner using either a porous tube or in-line static generators.

Other References

R. H. Yoon et al "The Effect of Bubble Size on Fine Coal Flotation", Coal Preparation, 1986, vol. 2, pp. 179-192
M. J. Mankosa et al "The Effect of Media Size in Stirred Bull Mill Grinding of Coal", Power Technology, 19 (1986) pp. 75-82
Yoon et al, "Improvements in Recovery and Selectivity with the Microbubble Flotation Process", 2nd Annual Pitts. Coal Conference Sep. 16-20, 1985 pp. 43-55
Sebba et al "The Use of Micron Sized Bubble in Mineral Processing", Interfacial Phenomena in Mineral Processing pp. 161-172
Yoon et al, "Cleaning of Ultrafine Coal by Microbubble Flotation" 1st Annual Pittsburgh Coal Conference, Sep. 17-21, 1984 pp. 891-897
Halsey et al "Cleaning of Fine Coal by Flotation Using Colloidal Gas Aphrons", Preceeding of the Technical Program May 11-13, 1982 pp. 76-80
Yoon, "Flotation of Coal Using Microbubbles and Inorganic Salts", Mining Congress Journal Dec. 1982 pp. 76-80
Yoon et al "A Preliminary Investigation on the Application of Colloidal Gas Aphrons for Fine Coal Cleaning" May 11-13, 1982 pp. 357-36