Enhanced activated sludge as drilling mud additive

Patent metadata

Field	Value
Publication number	US-10501674-B2
Application number	US-201816032386-A
Country	US
Kind code	B2
Filing date	Jul 11, 2018
Priority date	Jul 11, 2017
Publication date	Dec 10, 2019
Grant date	Dec 10, 2019

Abstract

Performance of EAS as drilling fluid additive was compared with commercial lubricants in terms of lubricity and flow properties. Lubricants were evaluated using water-based drilling mud at lubricant concentrations of 1.78, 3.11, 4.43, and 6.17 pounds per barrel (ppb). Experiments were carried out in a standard lubricity meter. The lubricity meter tests the ability of the lubricant in the drilling mud to reduce friction. Other parameters measured were plastic viscosity, gel strength, fluid loss, mud cake thickness, sand content, methylene blue test (MBT), alkalinity, and chlorides. These findings show that EAS will improve the properties of water-based drilling mud.

First claim

We claim:

1. A method of producing a drilling mud including the steps of:
(a) Obtaining a source of raw activated sludge;
(b) Fermenting the raw activated sludge under stress conditions to produce an enhanced activated sludge,
wherein said stress conditions include an environment relatively high in carbon compared to nitrogen;

(c) Removing water from the enhanced activated sludge; and
(d) Blending a quantity of the dewatered enhanced activated sludge into a base drilling mud to form a final drilling mud blend.

2. The method of claim 1 wherein said environment consists of a synthetic media with a carbon to nitrogen molar ratio greater than 50 but less than 90.

3. The method of claim 2 , wherein the dewatered enhanced activated sludge content of a final drilling mud blend is greater than 3 pounds per barrel.

4. The method of claim 2 , wherein the dewatered enhanced activated sludge content of a final drilling mud blend is greater than 5 pounds per barrel.

5. The method of claim 2 , wherein the dewatered enhanced sludge content of a final drilling mud blend is greater than 6 pounds per barrel.

6. The method of claim 2 , wherein an API fluid loss reduction is greater than 10 percent when comparing a final drilling mud blend to the base mud.

7. The method of claim 2 , wherein a torque reduction is greater than 30 percent when comparing a final drilling mud blend to the base mud.

8. The method of claim 2 , wherein a decrease in a coefficient of friction is greater than 25 percent when comparing a final drilling mud blend to the base mud.

Assignees

• Univ Louisiana At Lafayette

Inventors

• Tripuraneni Gopi Chand
• Zappi Mark
• Hernandez Rafael

Classifications

• C09K8/035 Primary

  Organic additives · CPC title

• C09K2208/34

  Lubricant additives · CPC title

• C09K8/506

  containing organic compounds · CPC title

• C09K8/32

  Non-aqueous well-drilling compositions, e.g. oil-based · CPC title

• C09K8/487

  Fluid loss control additives; Additives for reducing or preventing circulation loss · CPC title