Edward H. Greenwald
Engineering at Nancy Ln, Canonsburg, PA

4537599, Aug 27, 1985

Apr 16, 1984

6/598979

Edward H. Greenwald - McMurray PA

C10L 902

44 1SR

A process is disclosed for removing sulfur and ash, particularly clay and pyrite from coal particles having a mesh size of 30 or less. A slurry of coal particles is agitated in an ultrasonic mixer to separate the contaminants from the coal and weaken chemically-bonded contaminants on the coal surface. The clay and pyrite particles are dispersed as a colloid in the aqueous medium of the slurry. Treatment of the slurry with sonic energy also subdivides the particles along ash or clay seams. The slurry is then separated in a centrifuge and in froth-flotation cells so that coal particles greater than 2 microns are recovered and a slurry is again formed. The repulped slurry is then treated with sonic energy and ozone to release further quantities of surface components from the coal particles. The slurry is again treated in a centrifuge and coal particles 2 microns and greater are recovered. The slurry is normalized before each treatment with sonic energy and ozone to a pH of 6-9 to maintain the released contaminants as colloids suspended in the aqueous medium of the slurry.

4662894, May 5, 1987

Jul 18, 1985

6/756183

Edward H. Greenwald - McMurray PA

C10L 132

44 51

A process for producing a coal-water mixture includes forming dilatant coal particles in an aqueous coal feedstock mixture by treatment with ozone and classifying the coal feedstock mixture by treatment with ozone and classifying the coal feedstock to form first and second coal feed streams each comprised of differently-classified coal particles. Separate surge vessels receive the coal particles in a liquid medium forming each coal feed stream is determined and an electrical signal is delivered to a microprocessor for controlling the portions of each stream which are mixed together in the presence of a dispersing agent to form a coal-water mixture. The coal-water mixture is comprised of at least 65% by weight coal particles, preferably 70%. The coal content may be increased and flow properties of the coal-water mixture improved by removing a minus 2-micron particle fraction which is predominantly clay from the feedstock and mixing a minus 2-micron fraction of coal particles with quantities of the first and second feed streams.

5236596, Aug 17, 1993

Jul 24, 1991

7/735386

Edward H. Greenwald - McMurray PA

B03D 300, B01D 2100, B01D 2128, C10L 910

210696

A method and apparatus for dewatering an aqueous coal slurry includes imparting high shear forces to the aqueous coal slurry in the presence of a peptizing agent to render coal particles hydrophobic by stripping clay from the coal particles and peptizing the clay in the aqueous medium of the slurry. The slurry is separating to recover coal particles and the aqueous medium is draining medium from the hydrophobic surface of the coal particles.

5795484, Aug 18, 1998

May 8, 1995

8/436761

Edward H. Greenwald - McMurray PA

B03D 300, B01D 2100, B01D 2128, C10L 910

210696

An ultra-fine coal particle fraction forms a coal product with particles that are dilatant due to the mechanical stripping of the clay contaminates from the coal surface and the subdividing of the clay to clay platelets which are peptized to maintain discreetness in an aqueous slurry. The coal particles are unflocculated and can produce an aqueously permeable barrier on a sieve. The ultrafine coal product has an increase of 100-150 BTU per pound and when combusted reduced Nox production of 20-40% is realized. In a 15. times. 0 micron coal fraction, the sulphur content is significantly reduced.

4521218, Jun 4, 1985

Feb 21, 1984

6/581538

Edward H. Greenwald - McMurray PA

C10L 132

44 51

A process for producing a coal-water mixture includes classifying a coal feedstock to form first and second coal feed streams each comprised of differently-classified coal particles. Separate surge vessels receive the coal particles to form separate feed streams. The distribution of coal particles in a liquid medium forming each coal feed stream is determined and an electrical signal is delivered to the microprocessor for controlling the portions of each stream which are mixed together in the presence of a dispersing agent and a stabilizing agent to form a coal-water mixture. The coal-water mixture is comprised of at least 65% by weight coal particles and this may be increased to about 82% by controlling the distribution of coal particles in the liquid medium forming each of the coal feed streams.

5413703, May 9, 1995

Jul 22, 1993

8/095862

Edward H. Greenwald - McMurray PA

B03D 300, B01D 2100, B01D 2128, C10L 910

210205

A method and apparatus for dewatering an aqueous coal slurry includes imparting high shear forces to the aqueous coal slurry in the presence of a peptizing agent to render coal particles hydrophobic by stripping clay from the coal particles and peptizing the clay in the aqueous medium of the slurry. The slurry is separating to recover coal particles and the aqueous medium is draining medium from the hydrophobic surface of the coal particles.