US4259251A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Treatment of effluent
Assignee: Internationale Octrooi Maatschappij Octropa BV
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Filing: 1980-02-07
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Granted: 1981-03-31
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Expires: 2000-02-07
Abstract
Abstract A process for the production of fatty acid soaps from sludge, especially sewage sludge, comprises extracting sludge having a solids content of at least 15% by weight with a non-polar solvent to provide an extract containing fatty matter, and subsequently saponifying the fatty matter in the presence of a dipolar aprotic solvent having a dielectric constant of at least 15 to produce fatty acid soaps.
Inventors
- 👤 John B. Akers
- 👤 David C. Peters
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:40
CPC Classifications
C; C11; C11D; C11D13/00; C11D13/02; C02; C02F; C02F1/00; C02F1/26; C02F11/00; C02F11/002; C11B; C11B13/00; C11D13/30; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/74
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
67 words
A process for the production of fatty acid soaps from sludge, which comprises the steps of: (i) extracting sludge, having a solids content of at least 15% by weight, with a non-polar solvent to provide an extract comprising fatty matter; and (ii) saponifying the fatty matter in the presence of a dipolar aprotic solvent having a dielectric constant of at least 15 to produce fatty acid soaps.
Claim 2
Dependent Claim
67 words
A process for the production of fatty acid soaps from sludge, which comprises the steps of: (i) extracting sludge, having a solids content of at least 15% by weight, with a non-polar solvent to provide an extract comprising fatty matter; and (ii) saponifying the fatty matter in the presence of a dipolar aprotic solvent having a dielectric constant of at least 15 to produce fatty acid soaps.
Claim 3
Dependent Claim
19 words
The process of claim 1, wherein the sludge has a solids content of from 25 to 50% by weight.
Claim 4
Dependent Claim
40 words
The process of claim 1, comprising the additional preliminary steps of heating sludge to a temperature of at least 100° C. and subsequently separating the heated sludge to provide sludge having a solids content of at least 15% by weight.
Claim 5
Dependent Claim
36 words
The process of claim 1, comprising the additional preliminary steps of contacting sludge with a flocculating agent and subsequently separating the flocculated sludge to provide sludge having a solids content of at least 15% by weight.
Claim 6
Dependent Claim
22 words
The process of claim 1, wherein the non-polar solvent is a hydrocarbon having from 4 to 14 carbon atoms in the molecule.
Claim 7
Dependent Claim
23 words
The process of claim 5, wherein the hydrocarbon is an aliphatic hydrocarbon chosen from hexane, kerosene, petroleum spirit, petroleum ether and mixtures thereof.
Claim 8
Dependent Claim
20 words
The process of claim 5, wherein the hydrocarbon is an aromatic hydrocarbon chosen from benzene, toluene, xylene and mixtures thereof.
Claim 9
Dependent Claim
12 words
The process of claim 1, wherein the dipolar aprotic solvent is acetone.
Claim 10
Dependent Claim
17 words
The process of claim 1, wherein the fatty acid soaps so obtained comprise sodium fatty acid soaps.
Claim 11
Dependent Claim
17 words
The process of claim 1, wherein the fatty acid soaps so obtained comprise calcium fatty acid soaps.
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) | 1984-03-30 | 1984-09-29 | 1985-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-30 | 1988-09-29 | 1989-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-30 | 1992-09-29 | 1993-03-31 | $7700.00 | Window Closed / Lapsed |