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US 2019/0100684 A1Published application
Method of drilling a subterranean geological formation with a drilling fluid composition comprising copper nitrate
AssigneeKing Fahd University of Petroleum and Minerals
InventorsSalah El-Din Elkatatny, Reyad Awwad Shawabkeh, Mohamed Ahmed Nasr El-Din Mahmoud
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Abstract
A drilling fluid composition comprising an aqueous base fluid, a viscosifier, and a H2S scavenger comprising copper nitrate, wherein the drilling fluid composition has a H2S sorption capacity from about 4.0 to about 6.0 gram per one milliliter of the drilling fluid composition; and a method of drilling a subterranean geological formation using thereof are provided. Various embodiments of the drilling fluid composition and the method are also provided.
Claims8
1:
- A method of drilling a subterranean geological formation, comprising:
- driving a drill bit to form a wellbore into the subterranean geological formation thereby producing a formation fluid that contains H2S;
- and
- injecting a drilling fluid composition into the subterranean geological formation through the wellbore,
- wherein the drilling fluid composition comprises
- an aqueous base fluid,
- a viscosifier, and
- a H2S scavenger comprising copper nitrate, and
- wherein copper nitrate present in the drilling fluid composition reacts with H2S present in the formation fluid to form copper sulfide;
- recovering the copper sulfide from the drilling fluid composition;
- and
- treating the copper sulfide with nitric acid to regenerate copper nitrate while concurrently forming elemental sulfur.
9 more elements
2:
- The method of claim 1, wherein the wellbore is a horizontal or a multilateral wellbore.
3:
- The method of claim 1, wherein a temperature of the wellbore ranges from 50 to 200° C.
4:
- The method of claim 1,
- wherein the wellbore contains a casing that is made of at least one metal selected from the group consisting of stainless steel, aluminum, and titanium, the casing is exposed to a gaseous mixture containing up to 12 vol % of H2S, and
- wherein a corrosion rate of the casing is no more than 0.0006 lb/ft2 after 6 hours of contacting with the drilling fluid composition.
5:
- The method of claim 4, wherein the corrosion rate of the casing is no more than 0.00084 lb/ft2 after 24 hours of contacting with the drilling fluid composition.
6:
- The method of claim 1,
- wherein the formation fluid is produced for at least 1 hour but no more than 4 hours, and
- wherein a concentration of H2S in the formation fluid is no more than 40 ppm.
7:
- The method of claim 1, further comprising:
- circulating the drilling fluid composition within the wellbore for at least 30 minutes but no more than 3 hours, after the injecting.
8-20. (canceled)