Method of producing free flowing solids

• US 4,546,612 A
• Filed: 02/21/1984
• Issued: 10/15/1985
• Est. Priority Date: 02/21/1984
• Status: Expired due to Fees

• Current Assignee: Arthur D. Little, Inc.
• Original Assignee: Arthur D. Little, Inc.
• Inventors: Santhanam, Chakra J.
• Primary Examiner(s): Sever, Frank
• Application Number:
  US06/581,704
• Time in Patent Office: 602 Days
• Field of Search: 62/46, 62/47, 62/48, 62/55, 423/437, 137/13, 406/197, 406/154
• US Class Current: 62/54.1
• CPC Class Codes: B01J 2/30 using agents to prevent the granules sticking together; Rendering particulate materials free flowing in general, e.g. making them hydrophobic
• CPC Class Codes: Y10T 137/0391 Affecting flow by the addition of material or energy

Abstract

A process as disclosed forming a non-agueous, free-flowing composition. The process involves treating a finely divided inorganic or organic material with liquid carbon dioxide to form a slurry. The treated material is separated from the slurry and shows suprising free-flowing, nonagglomerated behavior.

Claims

1. A process comprising forming a dry free-flowing composition substantially free of flow promoting and anti-agglomerating agents by

a. providing an organic or inorganic material in finely divided form;

b. mixing said material with liquid carbon dioxide to form a slurry; and

c. separating said mixed material from said slurry.

2. The process in accordance with claim 1 wherein said slurry has a temperature of between about -20°

C. to about 30°

C. and a pressure of between about 20 and about 100 atmospheres.

3. The process in accordance with claim 2 wherein said finely divided materials have particles sized to pass a U.S. 100-mesh screen.

4. The process in accordance with claim 3 wherein the volume percent of finely divided material in said slurry is between about 30 and about 70 percent.

5. The process in accordance with claim 1 wherein said material is selected from iron ore, limestone, sulfur, potash, copper concentrate, or gelsonite.

6. The process in accordance with claim 1 wherein said separating occurs by expanding said slurry with the addition of heat.

7. The process in accordance with claim 6 wherein said expanded and heated slurry is passed into a cyclone separator having a bag filter mounted thereon and in fluid communication therewith whereby the expanded and heated slurry passes first through the cyclon separator, then through the bag filter.

8. The process in accordance with claim 1 wherein the finely divided material has a particle size distribution of from about 300 μ

m in diameter to about 40 μ

m in diameter.

9. The process in accordance with claim 1 wherein said separated material is pneumatically conveyed, the ratio of gas to treated material being from about 1:

5 to about 1;

50.

10. The process in accordance with claim 9 wherein said pneumatically conveyed material is a fire extinguishant.

11. The process in accordance with claim 1 wherein said material is coal.

12. The process in accordance with claim 11 wherein said separating of said mixed material from said slurry comprises expanding the slurry from a pressure of from about 900 to about 1000 psig. to a pressure of about 300 to about 600 psig. and then heating the slurry to form a gas-solid mixture.