US3978197A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wood fly ash reduction method
Assignee: Individual
•
Filing: 1975-08-25
•
Granted: 1976-08-31
•
Expires: 1995-08-25
Abstract
Abstract A method is disclosed for substantially reducing the potassium oxide context of wood fly ash contained in the combustion products generated during the burning of wood particles. The method disclosed involves mixing an alkali metal silicate, a secondary alkali metal compound and silica with the wood particles, burning the mixture, and withdrawing a stable, potassium oxide containing silicate product from the flue gases.
Inventors
- 👤 Erwin C. Betz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:23
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/20; C01B33/32; Y; Y02; Y02E; Y02E50/00; Y02E50/10; Y02E50/30
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
160 words
A method for reducing the potassium oxide content of the wood fly ash contained in the combustion products generated by the burning of wood particles, which comprises: mixing with the wood particles, an alkali metal silicate having a melting point below 1200° C, a secondary alkali metal compound having a melting point below 1200° C, and silica; burning the mixture; and withdrawing a stable potassium oxide containing silicate product having a melting point below 1200° C from the combustion products as a molten slag; wherein the alkali metal silicate, the secondary alkali metal compound, and the silica are present in amounts effective to form the stable silica product in the presence of wood particles containing potassium oxide; wherein the secondary alkali compound has a melting point not greater than the melting point of the stable silicate product; and wherein the mixture is kept deficient in alkali metal silicate in order to withdraw the potassium oxide from the wood fly ash.
Claim 2
Independent Claim
160 words
A method for reducing the potassium oxide content of the wood fly ash contained in the combustion products generated by the burning of wood particles, which comprises: mixing with the wood particles, an alkali metal silicate having a melting point below 1200° C, a secondary alkali metal compound having a melting point below 1200° C, and silica; burning the mixture; and withdrawing a stable potassium oxide containing silicate product having a melting point below 1200° C from the combustion products as a molten slag; wherein the alkali metal silicate, the secondary alkali metal compound, and the silica are present in amounts effective to form the stable silica product in the presence of wood particles containing potassium oxide; wherein the secondary alkali compound has a melting point not greater than the melting point of the stable silicate product; and wherein the mixture is kept deficient in alkali metal silicate in order to withdraw the potassium oxide from the wood fly ash.
Claim 3
Dependent Claim
29 words
The method of claim 1, wherein the alkali metal silicate, the secondary alkali metal compound, and the silica are mixed with the wood particles as they are being burned.
Claim 4
Dependent Claim
27 words
The method of claim 1, wherein the alkali metal silicate, the secondary alkali metal compound, and the silica are mixed with the wood particles prior to burning.
Claim 5
Dependent Claim
29 words
The method of claim 1, wherein the alkali metal silicate is selected from the group consisting of potassium tetrasilicate, potassium metasilicate, potassium disilicate, sodium lithium metasilicate, and sodium disilicate.
Claim 6
Dependent Claim
30 words
The method of claim 1, wherein the secondary alkali metal compound is selected from the group consisting of alkali metal carbonates, alkali metal hydroxides, and a second alkali metal silicate.
Claim 7
Dependent Claim
25 words
The method of claim 1, wherein the secondary alkali metal compound is selected from the group consisting of lithium carbonate, sodium carbonate, and potassium carbonate.
Claim 8
Dependent Claim
24 words
The method of claim 1, wherein the stable potassium oxide containing silicate product is a potassium lithium silicate or a sodium potassium lithium silicate.
Claim 9
Dependent Claim
52 words
The method of claim 7, wherein the stable potassium oxide containing silicate product is selected from the group consisting of 2K 2 O.Li 2 O.6SiO 2 , 5K 2 O.Li 2 O. 4SiO 2 , K 2 O.Li 2 O.4SiO 2 , and Na 2 O.K 2 O.Li 2 O.6SiO 2 .
Claim 10
Dependent Claim
53 words
The method of claim 1, wherein from 0.5 to 3 moles of the alkali metal silicate, from 0.5 to 1.5 moles of the secondary alkali metal compound, and from 2 to 6 moles of the silica are mixed with the wood particles per mole of potassium oxide present in the wood fly ash.
References Cited (Backward Citations)
US1668643A
Cited
US1955574A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-31 | 1980-03-01 | 1980-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-31 | 1984-03-01 | 1984-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-31 | 1988-03-01 | 1988-08-31 | $7700.00 | Window Closed / Lapsed |