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US4296813A Expired / Lapsed US ⏱️ 0.0 years remaining

Well cementing

Assignee: REED LIGNIN Inc A CORP OF DE
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Filing: 1977-02-07
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Granted: 1981-10-27
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Expires: 1997-02-07
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Abstract

Abstract Wells and like borings into the earth's surface, especially those for the production of petroleum and gas, are very well and efficaciously cemented with cement compositions or pastes containing, as their effective gel control and cement set retardation agent, an additive that is a resulfonated, alkaline oxidized, hydrolyzed, partially desulfonated lignosulfonate product.

Inventors

  • 👤 William J. Detroit
  • 👤 Michael E. Sanford

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 06:18
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/42; C09K8/46; C04; C04B; C04B24/00; C04B24/16; C04B24/18

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 131 words
In the process of drilling wells and borings into the earth's surface, including the injection of a hydraulic cement mixture thereinto, the improvement that comprises including in said hydraulic cement mixture, between about 0.05 percent and about 3 percent by weight of the resulting mixture, of a retarding agent composition for said hydraulic cement mixture that is an alkaline oxidized, hydrolyzed, partially desulfonated and subsequently resulfonated lignosulfonate, said resulfonated lignosulfonate having substituted therein as the resulfonation units, those of the formula: --SO.sub.3 H, said resulfonated lignosulfonate containing, on a percent by weight basis, based on composition weight, between about 11/2 weight percent and about 15 weight percent of total sulfur in combined organic sulfonic sulfonate form; said lignosulfonate prior to resulfonation having a relative molecular size of substantially 1,000 to 20,000.
Claim 2
Dependent Claim 131 words
In the process of drilling wells and borings into the earth's surface, including the injection of a hydraulic cement mixture thereinto, the improvement that comprises including in said hydraulic cement mixture, between about 0.05 percent and about 3 percent by weight of the resulting mixture, of a retarding agent composition for said hydraulic cement mixture that is an alkaline oxidized, hydrolyzed, partially desulfonated and subsequently resulfonated lignosulfonate, said resulfonated lignosulfonate having substituted therein as the resulfonation units, those of the formula: --SO.sub.3 H, said resulfonated lignosulfonate containing, on a percent by weight basis, based on composition weight, between about 11/2 weight percent and about 15 weight percent of total sulfur in combined organic sulfonic sulfonate form; said lignosulfonate prior to resulfonation having a relative molecular size of substantially 1,000 to 20,000.
Claim 3
Dependent Claim 26 words
A process as claimed in claim 1, wherein said retarding agent composition includes between about 23/4 and about 10 weight percent of said total combined sulfur.
Claim 4
Dependent Claim 26 words
A process as claimed in claim 1, wherein said retarding agent composition includes about 41/2 weight percent and about 61/2 weight percent of total combined sulfur.
Claim 5
Dependent Claim 22 words
A process as claimed in claim 1, wherein said retarding agent composition is present in the form of an alkali metal salt.
Claim 6
Dependent Claim 14 words
A process as claimed in claim 4, wherein said salt is a sodium salt.
Claim 7
Dependent Claim 36 words
A process as claimed in claim 1, wherein said composition is further characterized by a relatively constant relative molecular size range with a molecular size variation within said range of not more than about 20 percent.
Claim 8
Dependent Claim 20 words
A process as claimed in claim 6, wherein said relative molecular size range variation is not more than 10 percent.
Claim 9
Dependent Claim 55 words
A process as claimed in claim 1, wherein said retarding agent composition is further characterized in having the introduced sulfonate units substituted at least substantially, in the resulfonated, alkaline oxidized, hydrolyzed, partially desulfonated lignosulfonate material, in one or more of the ortho or para positions on the aromatic rings of the lignin molecules present therein.
Claim 10
Dependent Claim 30 words
A process as claimed in claim 8, wherein said substituted introduced sulfonate units are located predominantly in the ortho or para, or both, positions of said aromatic lignin molecule rings.
Claim 11
Dependent Claim 32 words
A process as claimed in claim 1, wherein said combined organic sulfonic sulfur is present upon completion of resulfonation in an amount by weight of from 2.75 percent to about 10 percent.
Claim 12
Dependent Claim 31 words
A process as claimed in claim 9, wherein said combined organic sulfonic sulfur is present upon completion of resulfonation in an amount of from about 4.5 percent to about 6.5 percent.
Claim 13
Dependent Claim 41 words
A process as claimed in claim 1, wherein said resulfonation is undertaken in an aqueous medium and in the presence of a reactant composition comprising about 5 percent to 40 percent, by weight of said desulfonated lignosulfonate, of alkali metal sulfite.
Claim 14
Dependent Claim 15 words
A process as claimed in claim 12, wherein said sulfite is an alkali metal bisulfite.
Claim 15
Dependent Claim 13 words
A process as claimed in claim 13 wherein said sulfite is sodium bisulfite.
Claim 16
Dependent Claim 36 words
A process as claimed in claim 1, wherein said lignosulfonate after resulfonation is characterized in being substantially completely soluble in each of aqueous saline solutions and acid media having a pH of at least about 1.5.
Claim 17
Dependent Claim 55 words
A process as claimed in claim 1, wherein said lignosulfonate prior to resulfonation is characterized by a pH in aqueous solution of 8.5 percent to 9.2 percent; a total sulfur content of 2.5 percent to 2.9 percent by weight; the absence of reducing sugars; and a lignosulfonate content of at least 99 percent by weight.
Claim 18
Dependent Claim 18 words
A process as claimed in claim 16, wherein said resulfonated lignosulfonate has a relative molecular size of 4200.
Claim 19
Dependent Claim 19 words
A process as claimed in claim 16, wherein said resulfonated lignosulfonate has a relative molecular size of about 3500.

References Cited (Backward Citations)

US3100526A Cited
US3582375A Cited
US3754953A Cited
US3723145A Cited
US3748159A Cited
US4047567A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-10-26 1985-04-27 1985-10-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-10-26 1989-04-27 1989-10-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-10-26 1993-04-27 1993-10-27 $7700.00 Window Closed / Lapsed

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