Drilling mud with enhanced activated sludge additive

Patent metadata

Field	Value
Publication number	US-11639458-B2
Application number	US-201916674043-A
Country	US
Kind code	B2
Filing date	Nov 5, 2019
Priority date	Jul 11, 2017
Publication date	May 2, 2023
Grant date	May 2, 2023

Abstract

In order to substantially reduce friction during drilling operations, specialized lubricants need to be added to drilling fluid recipes. In general, lubricants reduce friction by forming a thin film of liquid that separates the solid surfaces in contact. The primary objective of this research is to evaluate the performance of enhanced activated sludge (EAS) as a lubricant in drilling fluids. EAS is activated sludge rich in lipids. The mixed consortium of microorganism in waste water treatment facilities in grown under a high carbon/nitrogen ratio to trigger lipid accumulation.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 composition of drilling mud comprising:
(a) A fluid;
(b) Weighting materials to obtain a density greater than the fluid; and
(c) Activated sludge, wherein the activated sludge is fermented under stress conditions to produce an enhanced activated sludge with an increased lipid content, wherein said stress conditions include an environment relatively high in carbon to nitrogen.

2. The composition of claim 1 wherein the enhanced activated sludge has a lipid content of greater than five percent dry weight.

3. The composition of claim 2 wherein said drilling mud contains greater than 1 pound per barrel of enhanced activated sludge.

4. The composition of claim 2 wherein said drilling mud contains greater than 3 pound per barrel of enhanced activated sludge.

5. The composition of claim 2 wherein said drilling mud contains greater than 5 pound per barrel of enhanced activated sludge.

6. The composition of claim 1 wherein the enhanced activated sludge has a lipid content of greater than ten percent dry weight.

7. The composition of claim 1 wherein the enhanced activated sludge has a lipid content of greater than fifteen percent dry weight.

Assignees

• Univ Louisiana At Lafayette

Inventors

• Tripuraneni Gopi Chand
• Zappi Mark
• Hernandez Rafael

Classifications

• C09K2208/34

  Lubricant additives · CPC title

• C09K8/487

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

• C09K8/506

  containing organic compounds · CPC title

• C09K8/035 Primary

  Organic additives · CPC title

• C09K8/32

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