Well cementing
AssigneeAmerican Can Company
InventorsWilliam John Detroit, Michael Elliot Sanford
Life of this patent
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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.
Claims30
In a cementing composition comprised of a hydraulic cement, a retarding agent additive therefor which is, in an amount between about 0.05 percent and about 3 percent based on cement composition weight;
- an alkaline oxidized, hydrolyzed, partially desulfonated and subsequently resulfonated lignosulfonate, said resulfonated lignosulfonate having substituted herein as the resulfonation units, those of the formula:
- --(CH.sub.2).sub.x --SO.sub.3 H, wherein x has a numerical integral value from 0 to 3, and alkali metal salt derivatives thereof;
- said resulfonated lignosulfonate containing, on a percent by weight basis, based on lignosulfonate weight, between about 11/2 percent and about 15 percent of total sulfur in combined organic sulfonic sulfonate form;
- said lignosulfonate prior to resulfonation having a relative molecular size of substantially 1000 to 20,000.
A method or preparing cementing compositions which comprises adding to and dispersing in a hydraulic cement mixture of at least about 0.05 percent, based on resulting composition weight, of a retarding agent for the composition which is
- an alkaline oxidized, hydrolyzed, partially desulfonated and subsequently resulfonated lignosulfonate, said resulfonated lignosulfonate havine substituted therein as the resulfonation units, those of the formula:
- --(CH.sub.2).sub.x --SO.sub.3 H, wherein x has a numerical integral value from 0 to 3, and alkali metal salt derivatives thereof;
- said resulfonated lignosulfonate containing, based on lignosulfonate weight, between about 11/2 percent and about 15 percent of total sulfur in combined organic sulfonic sulfonate form.
In a cementing composition comprised of a hydraulic cement, a retarding agent additive therefor, in an amount of at least 0.05 percent based on cement composition weight, which is
- a lignosulfonate derived from sulfite waste liquor that has been subjected to alkaline oxidation, hydrolysis and partial desulfonation with subsequent resulfonation;
- said lignosulfonate prior to resulfonation containing combined organic sulfonic sulfur after partial desulfonation of between about 0.5 percent and about 5.0 percent when calculated on the basis of the amount of sulfur present by weight in said lignosulfonate and containing from about 1.5 percent to about 15 percent by weight upon completion of said resulfonation.
Dependencies are inferred from the claim text.