Compositions and methods for well completions
US-9139476-B2 · Sep 22, 2015 · US
US9975807B2 · US · B2
| Field | Value |
|---|---|
| Publication number | US-9975807-B2 |
| Application number | US-201113881709-A |
| Country | US |
| Kind code | B2 |
| Filing date | Oct 28, 2011 |
| Priority date | Nov 5, 2010 |
| Publication date | May 22, 2018 |
| Grant date | May 22, 2018 |
A practical reading order for non-experts. Skip the full description unless you need deep technical detail.
What the patent document calls the invention.
A short plain-language summary of the technical disclosure.
Who owns or filed the patent and who is credited as inventor.
Filing, priority, publication, and grant dates set the timeline.
The legal scope of protection — read this for what is actually claimed.
Technology tags used to group this patent with similar filings.
Prior art links and similar publications in this corpus.
Official abstract text for this publication.
Cement retarders are based on blends of lignosulfonate compounds, borate compounds and gluconate compounds. The compounds are present in certain ratios that allow the retarders to operate at temperatures and pressures up to and exceeding about 176° C. and 152 MPa. The retarders may also be provided in liquid form, improving their suitability for use at offshore well-site locations.
Opening claim text (preview).
The invention claimed is: 1. A method for cementing a subterranean well, comprising: (i) providing a well-cementing composition comprising Portland cement, water and a retarder comprising a lignosulfonate compound, a borate compound and a gluconate compound, wherein the lignosulfonate compound and the borate compound are present in the composition at a lignosulfonate compound:borate-compound concentration ratio that is lower than 0.75:1, and the lignosulfonate compound, the borate compound and the gluconate compound are present in the composition at a lignosulfonate compound:borate compound:gluconate compound concentration ratio that is between 0.1:1.0:0.1 and 0.5:1.0:0.5 by weight; and (ii) placing the composition in the well, wherein the lignosulfonate compound is an oxylignin and the borate compound is sodium tetraborate decahydrate, sodium pentaborate decahydrate or both; wherein the composition further comprises AMPS-acrylamide copolymer or styrene butadiene latex. 2. The method of claim 1 , wherein the lignosulfonate compound comprises sodium lignosulfonate, and the gluconate compound comprises sodium gluconate. 3. The method of claim 2 , wherein the sodium lignosulfonate and sodium gluconate are present at a sodium lignosulfonate:sodium gluconate concentration ratio between 70:30 and 30:70 by weight. 4. The method of claim 1 , wherein the retarder is provided in liquid form. 5. A method of retarding a Portland cement slurry, comprising: mixing a blend comprising a lignosulfonate compound, a borate compound and a gluconate compound with a Portland cement slurry, wherein the lignosulfonate compound and the borate compound are present in the blend at a lignosulfonate compound:borate-compound concentration ratio that is lower than 0.75:1, and the lignosulfonate compound, the borate compound and the gluconate compound are present in the blend at a lignosulfonate compound:borate compound:gluconate compound concentration ratio between 0.1:1.0:0.1 and 0.5:1.0:0.5 by weight, wherein the lignosulfonate compound is an oxylignin and the borate compound is sodium pentaborate decahydrate, sodium tetraborate decahydrate or both; wherein the composition further comprises AMPS-acrylamide copolymer or styrene butadiene latex. 6. The method of claim 5 , wherein the lignosulfonate compound comprises sodium lignosulfonate, and the gluconate compound comprises sodium gluconate. 7. The method of claim 6 , wherein the sodium lignosulfonate and sodium gluconate are present at a sodium lignosulfonate:sodium gluconate concentration ratio between 70:30 and 30:70 by weight. 8. The method of claim 5 , wherein the blend is provided in liquid form.
Portland cements · CPC title
Premixtures of ingredients · CPC title
containing additives for specific purposes · CPC title
Methods or devices for cementing, for plugging holes, crevices or the like · CPC title
Set retarders · CPC title
Related publications grouped by family.
Answers are generated from the same data shown on this page.