US5245121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reduced leaching of heavy metals from incinerator ashes
Assignee: Phillips Petroleum Co
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Filing: 1991-08-08
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Granted: 1993-09-14
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Expires: 2011-08-08
Abstract
Abstract A waste material which contains chromium and/or lead impurities is treated by mixing the waste material with diatomaceous earth and/or sodium borate and then heating the mixture in a free oxygen containing gas at about 500°-1500° C., preferably in the presence of steam.
Inventors
- 👤 James W. Gall
- 👤 Ollie G. Buck
- 👤 Dennis R. Kidd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:55
CPC Classifications
A; A62; A62D; A62D3/00; A62D3/30; A62D3/33; A62D3/38; F; F23; F23G; F23G5/00; F23G5/02; A62D2101/00; A62D2101/20; A62D2101/24; A62D2101/40; A62D2101/43; A62D2203/00; A62D2203/04; A62D2203/10; F23G2201/00; F23G2201/70; F23G2201/701; Y; Y10; Y10S; Y10S588/00; Y10S588/901
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
72 words
A process for treating a waste material which contains at least one heavy metal containing impurity selected from the group consisting of chromium metal and chromium compounds comprising the steps of (a) mixing said waste material with an additive consisting essentially of diatomaceous earth and calcium hydroxide; and (b) heating the mixture obtained in step (a) with a free oxygen containing gas at a temperature of about 500° to about 1500° C.
Claim 2
Dependent Claim
72 words
A process for treating a waste material which contains at least one heavy metal containing impurity selected from the group consisting of chromium metal and chromium compounds comprising the steps of (a) mixing said waste material with an additive consisting essentially of diatomaceous earth and calcium hydroxide; and (b) heating the mixture obtained in step (a) with a free oxygen containing gas at a temperature of about 500° to about 1500° C.
Claim 3
Dependent Claim
19 words
A process in accordance with claim 1, wherein said waste material additionally contains at least one combustible carbonaceous material.
Claim 4
Dependent Claim
27 words
A process in accordance with claim 1, wherein said waste material is solid and said at least one heavy metal impurity is at least one chromium compound.
Claim 5
Dependent Claim
75 words
A process in accordance with claim 1, wherein the weight ratio of said diatomaceous earth to said at least one heavy metal, expressed as elemental metal, contained in said waste material is in the range of about 20:1 to about 200:1, and the weight ratio of said calcium hydroxide to said at least one heavy metal, expressed as elemental metal, contained in said waste material is in the range of about 0.5:1 to about 15:1.
Claim 6
Dependent Claim
22 words
A process in accordance with claim 1, wherein step (b) of said process is carried out for at least about 0.5 minute.
Claim 7
Dependent Claim
30 words
A process in accordance with claim 1, wherein step (b) of said process is carried out at a temperature in the range of about 700° C. to about 900° C.
Claim 8
Dependent Claim
24 words
A process in accordance with claim 6, wherein step (b) of said process is carried out for about 20 minutes to about 120 minutes.
Claim 9
Dependent Claim
15 words
A process in accordance with claim 1, wherein said free oxygen containing gas is air.
Claim 10
Dependent Claim
23 words
A process in accordance with claim 1, further comprising the step of disposing the solid residue obtained in step (b) in a landfill.
Claim 11
Dependent Claim
75 words
A process for treating a waste material which contains at least one heavy metal containing impurity selected from the group consisting of chromium metal and chromium compounds comprising the steps of (a) mixing said waste material with an additive consisting essentially of diatomaceous earth and calcium hydroxide, and (b) heating the mixture obtained in step (a) with a free oxygen containing gas and added steam at a temperature of about 500° to about 1500° C.
Claim 12
Dependent Claim
75 words
A process for treating a waste material which contains at least one heavy metal containing impurity selected from the group consisting of chromium metal and chromium compounds comprising the steps of (a) mixing said waste material with an additive consisting essentially of diatomaceous earth and calcium hydroxide, and (b) heating the mixture obtained in step (a) with a free oxygen containing gas and added steam at a temperature of about 500° to about 1500° C.
Claim 13
Dependent Claim
19 words
A process in accordance with claim 10, wherein said waste material additionally contains at least one combustible carbonaceous material.
Claim 14
Dependent Claim
27 words
A process in accordance with claim 10, wherein said waste material is solid and said at least one heavy metal impurity is at least one chromium compound.
Claim 15
Dependent Claim
75 words
A process in accordance with claim 10, wherein the weight ratio of said diatomaceous earth to said at least one heavy metal, expressed as elemental metal, contained in said waste material is in the range of about 20:1 to about 200:1, and the weight ratio of said calcium hydroxide to said at least one heavy metal, expressed as elemental metal, contained in said waste material is in the range of about 0.5:1 to about 15:1.
Claim 16
Dependent Claim
22 words
A process in accordance with claim 10, wherein step (b) of said process is carried out for at least about 0.5 minute.
Claim 17
Dependent Claim
30 words
A process in accordance with claim 10, wherein step (b) of said process is carried out at a temperature in the range of about 700° C. to about 900° C.
Claim 18
Dependent Claim
23 words
A process in accordance with claim 15, wherein step of said process is carried out for about 20 minutes to about 120 minutes.
Claim 19
Dependent Claim
34 words
A process in accordance with claim 10, wherein the volume ratio of said added steam to oxygen contained in said free oxygen containing gas is in the range of about 0.1:1 to about 2:1.
Claim 20
Dependent Claim
15 words
A process in accordance with claim 10, wherein said free oxygen containing gas is air.
Claim 21
Dependent Claim
23 words
A process in accordance with claim 10, further comprising the step of disposing the solid residue obtained in step (b) in a landfill.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-09-13 | 1997-03-15 | 1997-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-09-13 | 2001-03-15 | 2001-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-09-13 | 2005-03-15 | 2005-09-14 | $7700.00 | Window Closed / Lapsed |