§
Luxuse
Patent Intelligence
Sign In
← Back to Patent Explorer
US4417976A Expired / Lapsed US ⏱️ 0.0 years remaining

Dewatering of petroleum-containing sludges with recovery of the oil component

Assignee: BASF SE
•
Filing: 1981-12-22
•
Granted: 1983-11-29
•
Expires: 2001-12-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A process for dewatering petroleum-containing sludges by a two-stage method using finely divided additives and organic flocculants, wherein (a) finely divided additives, such as ash, coal, sand or mixtures of these, in a free-flowing form or as an aqueous suspension, are homogeneously dispersed in the petroleum-containing sludge, in an amount such that the total solids content of the resulting mixture is from 10 to 30% by weight, especially from 12 to 20% by weight, (b) this sludge mixture is treated with an aqueous solution of an organic flocculant, preferably of anionic nature, (c) the greater part of the sludge water is removed by gravity filtration, (d) the pre-dewatered sludge mixture is treated with an aqueous solution of aluminum salts or trivalent iron salts and (e) this mixture is substantially dewatered by pressure filtration, in the course of which the greater part of the petroleum present is also removed.

Inventors

  • 👤 Bruno Sander
  • 👤 Friedrich Hovemann
  • 👤 Kurt Scherling

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 17:43
CPC Classifications
C; C10; C10G; C10G33/00; C10G33/04; B; B01; B01D; B01D17/00; B01D17/02; B01D17/04; B01D17/047; B01D17/08; B01D37/00; B01D37/03; C02; C02F; C02F11/00; C02F11/12

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 131 words
A process for dewatering petroleum-containing sludges by a two-stage method using finely divided additives and organic flocculants which comprises: (a) homogeneously dispersing in the petroleum-containing sludge finely divided additives selected from the group consisting of ash, coal, sand or mixtures of these, in a free-flowing form or as an aqueous suspension, in an amount such that the total solids content of the resulting mixtures is from 10 to 30% by weight, (b) treating the sludge mixture with an aqueous solution of an organic flocculant, (c) removing the greater part of the sludge water by gravity filtration, (d) treating the pre-dewatered sludge with an aqueous solution of aluminum salts or trivalent iron salts and (e) pressure filtering the resulting mixture from step (d) to separate the petroleum and water from the solids.
Claim 2
Dependent Claim 131 words
A process for dewatering petroleum-containing sludges by a two-stage method using finely divided additives and organic flocculants which comprises: (a) homogeneously dispersing in the petroleum-containing sludge finely divided additives selected from the group consisting of ash, coal, sand or mixtures of these, in a free-flowing form or as an aqueous suspension, in an amount such that the total solids content of the resulting mixtures is from 10 to 30% by weight, (b) treating the sludge mixture with an aqueous solution of an organic flocculant, (c) removing the greater part of the sludge water by gravity filtration, (d) treating the pre-dewatered sludge with an aqueous solution of aluminum salts or trivalent iron salts and (e) pressure filtering the resulting mixture from step (d) to separate the petroleum and water from the solids.
Claim 3
Dependent Claim 44 words
The process of claim 1, wherein a part of the filter cake obtained from the pressure filtration is mechanically loosened, brought into a finely divided form and then dispersed homogeneously as an additive, in place of ash, coal or sand, in the petroleum-containing sludge.
Claim 4
Dependent Claim 24 words
The process of claim 1, wherein the solids content of the resulting mixtures formed in step (a) is from 12% to 20% by weight.
Claim 5
Dependent Claim 13 words
The process of claim 3, wherein the organic flocculant is of anionic nature.

References Cited (Backward Citations)

US1093098A Cited
US1547712A Cited
US1569695A Cited
US1887774A Cited
US2973314A Cited
US3165465A Cited
US3931005A Cited
SU520390A1 Cited
US4122009A Cited
US4299690A Cited
JPS54124559A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-11-28 1987-05-30 1987-11-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-11-28 1991-05-30 1991-11-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-11-28 1995-05-30 1995-11-29 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag