Patent DE1014167B successfully refreshed from Google Patents.
US4238430A
Expired / Lapsed
US
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Method for forming expanded cellular volcanic ash
Assignee: United States Vacuumite Corp
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Filing: 1979-07-30
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Granted: 1980-12-09
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Expires: 1999-07-30
Abstract
Abstract Disclosed is an apparatus and method for expanding particulate volcanic ash to produce an expanded substantially monocellular product having a loose bulk density of about 0.5 to about 15 pounds per cubic foot. The apparatus includes an enclosed vessel containing a zone heated to about 930° C. to about 1100° C. by a substantially horizontally projecting flame. The flame may be deviated from horizontal to control the residence time of the ash particles in the heated zone. The pressure in the vessel is maintained at least 10 millimeters of mercury less than atmospheric.
Inventors
- 👤 Harold L. Phillips
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:03
CPC Classifications
C; C04; C04B; C04B20/00; C04B20/02; C04B20/04; C04B20/06; C04B14/00; C04B14/02; C04B14/04; C04B14/14; C04B14/16
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
81 words
The method of forming expanded hollow substantially spherical bodies of volcanic ash comprising the steps of (a) dropping particulate bodies of volcanic ash through a substantially horizontally extending flame to thereby momentarily heat said particulate bodies to a temperature between about 930° C. and about 1100° C.; (b) thereafter immediately cooling said particulate bodies to a temperature below about 900° C.; and (c) maintaining the environment surrounding said particulate bodies during said heating and cooling at a pressure less than atmospheric.
Claim 2
Independent Claim
81 words
The method of forming expanded hollow substantially spherical bodies of volcanic ash comprising the steps of (a) dropping particulate bodies of volcanic ash through a substantially horizontally extending flame to thereby momentarily heat said particulate bodies to a temperature between about 930° C. and about 1100° C.; (b) thereafter immediately cooling said particulate bodies to a temperature below about 900° C.; and (c) maintaining the environment surrounding said particulate bodies during said heating and cooling at a pressure less than atmospheric.
Claim 3
Dependent Claim
38 words
The method set forth in claim 1 wherein said particulate bodies of volcanic ash have a loose bulk density of about 40 to about 65 pounds per cubic foot and contain less than about 15% water by weight.
Claim 4
Dependent Claim
37 words
The method set forth in claim 1 wherein the environment surrounding said particulate bodies during said heating and cooling is maintained at a pressure of from about 10 to about 15 millimeters of mercury less than atmospheric.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-09 | 1984-06-09 | 1984-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-09 | 1988-06-09 | 1988-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-09 | 1992-06-09 | 1992-12-09 | $7700.00 | Window Closed / Lapsed |