Patent USRE29783E successfully refreshed from Google Patents.
USRE29783E
Expired / Lapsed
US
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Process for treating aqueous chemical waste sludges and compositions produced thereby
Assignee: CONVERSION SYSTEMS Inc A CORP OF
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Filing: 1977-02-08
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Granted: 1978-09-26
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Expires: 1997-02-08
Abstract
Abstract Waste sludges containing small amounts of certain types of reactive materials are treated by adding to such sludges materials capable of producing aluminum ions, lime and/or sulfate bearing compounds to produce a composition having a sufficient concentration of sulfate ions, aluminum ions and equivalents thereof, and calcium ions and equivalents thereof. Fly ash is preferred source of aluminum ions for this purpose. Over a period of time such compositions harden by the formation of calcium sulfo-aluminate hydrates. Hardening of the sludge facilitates its disposition and may permit the reclamation of the land now occupied by large settling ponds for such sludge. Still further, the solidification of such settling ponds may provide permanent land fill which permits immediate use of the land without the necessity for removal of the sludge. Aggregate materials may also be incorporated in the solidified waste.
Inventors
- 👤 Charles L. Smith
- 👤 William C. Webster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:47
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/02; C04B28/06; C04B28/065; C02; C02F; C02F1/00; C02F1/66; C02F11/00; C02F11/008
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
211 words
The method of treating .Iadd.an .Iaddend.aqueous chemical waste .[.sludges.]. .Iadd.sludge including a sulfate compound .Iaddend.comprising adding to said .[.sludges.]. .Iadd.sludge .Iaddend.sufficient lime, .[.aluminum-containing material.]. .Iadd.fly ash .Iaddend.and water soluble sulfate compound to produce a composition having available sulfate ions, a second type of available ion selected from the group consisting of aluminum and ferric ions, the concentration of which is expressed in Al 2 O 3 equivalents, and a third type of available ions selected from the group consisting of calcium and magnesium, the concentration of which is expressed in CaO equivalents, wherein the composition, including available ions in said added lime, .[.aluminum-containing material.]. .Iadd.fly ash .Iaddend.and water soluble sulfate compounds includes at least 0.5 weight percent .[.--SO 4 .]. .Iadd.(--SO 4 ) -2 , .Iaddend.at least 0.2 weight percent Al 2 O 3 and equivalents thereof, and at least 0.5 weight percent CaO and equivalents thereof, .Iadd.the fly ash being present in said composition in an amount of at least 20% by weight of the amount of sludge in said composition, said composition being cementitiously hardenable through chemical reactions the products of which include calcium sulfo-aluminate hydrate or calcium alumino-sulfate hydrate, and allowing said composition to harden by chemical reaction to develop penetration resistance therein under atmospheric conditions. .Iaddend. .[.
Claim 2
Independent Claim
211 words
The method of treating .Iadd.an .Iaddend.aqueous chemical waste .[.sludges.]. .Iadd.sludge including a sulfate compound .Iaddend.comprising adding to said .[.sludges.]. .Iadd.sludge .Iaddend.sufficient lime, .[.aluminum-containing material.]. .Iadd.fly ash .Iaddend.and water soluble sulfate compound to produce a composition having available sulfate ions, a second type of available ion selected from the group consisting of aluminum and ferric ions, the concentration of which is expressed in Al 2 O 3 equivalents, and a third type of available ions selected from the group consisting of calcium and magnesium, the concentration of which is expressed in CaO equivalents, wherein the composition, including available ions in said added lime, .[.aluminum-containing material.]. .Iadd.fly ash .Iaddend.and water soluble sulfate compounds includes at least 0.5 weight percent .[.--SO 4 .]. .Iadd.(--SO 4 ) -2 , .Iaddend.at least 0.2 weight percent Al 2 O 3 and equivalents thereof, and at least 0.5 weight percent CaO and equivalents thereof, .Iadd.the fly ash being present in said composition in an amount of at least 20% by weight of the amount of sludge in said composition, said composition being cementitiously hardenable through chemical reactions the products of which include calcium sulfo-aluminate hydrate or calcium alumino-sulfate hydrate, and allowing said composition to harden by chemical reaction to develop penetration resistance therein under atmospheric conditions. .Iaddend. .[.
Claim 3
Dependent Claim
16 words
A method, as recited in claim 1, wherein said aluminum ion yielding material is fly ash..].
Claim 4
Dependent Claim
62 words
A method, as recited in claim 1, wherein the weight ratios of available ions in said composition are in the range (Al +3 and Ca +2 include Al +3 and Ca +2 equivalents, respectively): Al +3 :Ca +2 from 1:10 to 1:2 Al +3 :(SO 4 ) -2 from 1:2 to 1:10 Ca +2 :(SO 4 ) -2 from 1:2 to 2:1
Claim 5
Dependent Claim
23 words
A method, as recited in claim 1, wherein said water soluble sulfate is calcium sulfate anhydrite, calcium sulfate hemihydrate, or calcium sulfate dihydrate.
Claim 6
Dependent Claim
37 words
A method, as recited in claim 1, wherein said sludge is the waste product of an acid making plant, said method consisting of adding lime and fly ash to obtain a composition as recited in claim 1.
Claim 7
Dependent Claim
38 words
A method, as recited in claim 1, wherein said sludge is the pickle liquor waste product of a steel plant, said method consisting of adding lime and fly ash to obtain a composition as recited in claim 1.
Claim 8
Dependent Claim
256 words
A composition comprising the reaction product of an aqueous chemical waste sludge .Iadd.including a sulfate compound .Iaddend.and selected additive materials said additive materials being selected so that the total composition of said additive materials and said sludge includes .Iadd.fly ash in a proportion of at least 20% of said sludge, .Iaddend.available sulfate ions, a second type of available ion selected from the group consisting of aluminum and ferric ions, the concentration of which is expressed in Al 2 O 3 equivalents, and a third type of available ions selected from the group consisting of calcium and magnesium, the concentration of which is expressed in CaO equivalents, wherein the composition includes at least 0.5 weight percent .[.--SO 4 .]. .Iadd.(--SO 4 ) -2 , .Iaddend.at least 0.2 weight percent Al 2 O 3 and equivalents thereof, and at least 0.5 weight percent CaO and equivalents thereof, wherein the weight ratios of available ions in said composition are in the range (Al +3 and Ca +2 includes Al +3 and Ca +2 equivalents, respectively): Al +3 :Ca +2 from 1:10 to tol: 2 Al +3 :(SO 4 ) -2 from 1:2 to 1:10 Ca +2 :(SO 4 ) -2 from 1:2 to 2:1, .Iadd. said composition, prior to reaction, being cementitiously hardenable through chemical reactions the products of which include calcium sulfo-aluminate hydrate or calcium alumino-sulfate hydrate, and allowing said composition to harden by chemical reaction to develop penetration resistance therein under atmospheric conditions. .Iaddend. .[.8. A composition, as recited in claim 7, wherein said aluminum ions yielding
Claim 9
Dependent Claim
13 words
material is fly ash..]. 9. A composition as recited in claim 7, wherein
Claim 10
Dependent Claim
25 words
said sludge is the waste product of an acid making plant. 10. A composition as recited in claim 7, wherein said sludge is the pickle
Claim 11
Dependent Claim
214 words
liquor waste product of a steel plant. 11. The method of making a cementitious composition comprising adding .[.the.]. .Iadd.to an .Iaddend.aqueous chemical waste .[.sludges.]. .Iadd.sludge including a sulfate compound, .Iaddend.sufficient lime, .[.aluminum-containing materials.]. .Iadd.fly ash .Iaddend.and water soluble sulfate compound to produce a composition having available sulfate ions, a second type of available ions selected from the group consisting of aluminum and iron ions, the concentration of which is expressed in Al 2 O 3 equivalents, and a third type of available ions selected from the group consisting of calcium and magnesium, the concentration of which is expressed in CaO equivalents, wherein the composition includes at least 0.5 weight percent .[.--SO 4 .]. .Iadd.(SO 4 ) -2 .Iaddend. at least 0.2 weight percent Al 2 O 3 and equivalents thereof, and at least 0.5 weight percent CaO and equivalents thereof, .Iadd.the fly ash being present in said composition in an amount of at least 20% by weight of the amount of sludge in said composition, said composition being cementitiously hardenable through chemical reactions the products of which include calcium sulfo-aluminate hydrate or calcium alumino-sulfate hydrate, and allowing said composition to harden by chemical reaction to develop penetration resistance therein under atmospheric conditions. .Iaddend. .[.12. A method, as recited in claim 11, wherein said aluminum
Claim 12
Dependent Claim
59 words
ion yielding material is fly ash..]. 13. A method, as recited in claim 11, wherein the weight ratios of available ions in said composition are in the range (Al +3 and Ca +2 include Al +2 and Ca +2 equivalents respectively): Al +3 :Ca +2 from 1:10 to 1:2 Al +3 :(SO 4 ) -2 from 1:2 to 1:10
Claim 13
Dependent Claim
27 words
Ca +2 :(SO 4 ) -2 from 1:2 to 2:1 14. A method, as recited in claim 11, wherein said water soluble sulfate is calcium sulfate anhydrite,
Claim 14
Dependent Claim
37 words
calcium sulfate hemihydrate, or calcium sulfate dihydrate. 15. A method, as recited in claim 11, wherein said sludge is the waste product of an acid making plant, said method consisting of adding lime and fly ash to
Claim 15
Dependent Claim
191 words
obtain a composition as recited in claim 11. 16. A method, as recited in claim 11, wherein said sludge is the pickle liquor waste product of a steel plant, said method consisting of adding lime and fly ash to obtain a composition as recited in claim 11. .Iadd. 17. A method, as recited in claim 11, wherein said composition is damp and compactible. .Iaddend..Iadd. 18. A method, as recited in claim 11, wherein said composition is pourable. .Iaddend..Iadd. 19. A method, as recited in claim 11, wherein the ratio of calcium and magnesium ions in said composition to sulfate ions in said composition is in the range of from 2:1 to 1:2. .Iaddend..Iadd. 20. A method, as recited in claim 1, wherein said composition includes from 0.5 to 4 parts fly ash per part sludge (by weight). .Iaddend..Iadd. 21. A composition, a recited in claim 7, wherein, prior to reaction, said composition includes from 0.5 to 4 parts fly ash per part sludge (by weight). .Iaddend..Iadd. 22. A method, as recited in claim 11, wherein said composition includes from 0.5 to 4 parts fly ash per part sludge (by weight). .Iaddend.
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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) | 1981-09-25 | 1982-03-27 | 1982-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-25 | 1986-03-27 | 1986-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-25 | 1990-03-27 | 1990-09-26 | $7700.00 | Window Closed / Lapsed |