Please enable JavaScript for this site to function properly.
OnePetro
  • Help
  • About us
  • Contact us
Menu
  • Home
  • Journals
  • Conferences
  • Log in / Register

Log in to your subscription

and
Advanced search Show search help
  • Full text
  • Author
  • Company/Institution
  • Publisher
  • Journal
  • Conference
Boolean operators
This OR that
This AND that
This NOT that
Must include "This" and "That"
This That
Must not include "That"
This -That
"This" is optional
This +That
Exact phrase "This That"
"This That"
Grouping
(this AND that) OR (that AND other)
Specifying fields
publisher:"Publisher Name"
author:(Smith OR Jones)

Mechanistic Understanding of Microbial Plugging for Improved Sweep Efficiency

Authors
Greg Gandler (The University of Texas at Austin) | Akpobari Gbosi (The University of Texas at Austin) | Steven Lawrence Bryant (U. of Texas Austin) | Larry N. Britton (U. of Texas Austin)
DOI
https://doi.org/10.2118/100048-MS
Document ID
SPE-100048-MS
Publisher
Society of Petroleum Engineers
Source
SPE/DOE Symposium on Improved Oil Recovery, 22-26 April, Tulsa, Oklahoma, USA
Publication Date
2006
Document Type
Conference Paper
Language
English
ISBN
978-1-55563-157-4
Copyright
2006. Society of Petroleum Engineers
Disciplines
2.2.2 Perforating, 1.10 Drilling Equipment, 5.7.2 Recovery Factors, 1.6.9 Coring, Fishing, 4.3.4 Scale, 5.4.1 Waterflooding, 2.4.3 Sand/Solids Control, 5.3.1 Flow in Porous Media
Downloads
3 in the last 30 days
344 since 2007
Show more detail
View rights & permissions
SPE Member Price: USD 8.50
SPE Non-Member Price: USD 25.00

Abstract

Microbial plugging has been proposed as an effective low cost method of permeability reduction. To optimize the field implementation, better mechanistic and volumetric understanding of biofilm growth within a porous medium is needed. In particular, the engineering design hinges upon a quantitative relationship between amount of nutrient consumption, amount of growth, and degree of permeability reduction. As a first step toward such a relationship, a Pseudomonas aeruginosa culture was inoculated into columns of glass beads and Berea sandstone cores. A growth substrate with acetate as carbon and energy source was injected continuously. Growth substrate utilization and permeability changes were used to track growth, and post-experiment in situ staining of biomass provided visual evidence of colonization and growth. Growth was observed as grainy coatings but in a spatially complex and unpredictable manner. Permeability was reduced noticeably in each experiment, but replicate experiments exhibited different growth rates and ultimate growth-induced permeability reduction. The experiments demonstrated that microbial growth is effective for reducing flow in porous media. Obtaining a mechanistic interpretation of the behavior will require a better understanding of the variability in microbe growth at the grain scale. 

Introduction

United States onshore oil fields have undergone extensive waterflooding. Many fields reach an economic limit at high watercuts because of the increased costs of lifting large amounts of fluids with only a small amount of produced oil. In many cases, high permeability thief zones contribute much of the produced water. Bypassed oil remaining in the lower permeability reservoir rock can be mobilized if injected fluids are effectively diverted from the thief zones to the remaining areas of the reservoir. Microbial plugging has been touted as a low cost, potentially high reward technology for increasing sweep efficiency by occluding thief zones in mature oil fields. Stimulating the growth of indigenous microbes is a particularly attractive version of this idea. This circumvents the twin challenges of cultivating a strain that will thrive at reservoir conditions and of propagating organisms to useful distances within the formation. This approach has been implemented with technical and economic success in the North Blowhorn Creek Unit (Vadie et al, 2002).

Quantitative modeling of the behavior of this and other microbial EOR techniques is difficult. In particular the relationship between the rate of consumption of microbial nutrients (e.g. acetate, dissolved oxygen) and the mechanism of permeability reduction (e.g. incremental growth of biofilms on all grain surfaces vs. local growth of colonies that block pores) is not well understood.

The aim of this study is to quantify biofilm induced permeability reductions for a model microbe in porous media columns. Permeability reductions were measured during flow experiments employing a single, well-characterized microbial species growing in a defined growth medium. Carbon source utilization and flow pressures were monitored concurrently. Images of the biofilms within the porous media were acquired by two methods to better understand biofilm location within the pores. Traditional batch growth experiments (no porous media) were conducted to determine growth kinetics independently of the flow experiments. 

Previous Work

Microbial induced permeability reductions in porous media have been verified on several fronts within many fields of science. Most experiments have shown that permeability reductions are normally between 65% and 95%. Cunningham and Characklis (1991) created a series of experiments in which several porous media of large permeability (between 98 and 2127 Darcy) were inoculated with Pseudomonas aeruginosa and permeability reduction was measured as biofilm grew. After growth was complete each sample had a permeability in the range of 3 to 7 Darcy. Their results indicated that final biofilm-altered permeabilities were similar, despite large differences in original permeability.

File Size  271 KBNumber of Pages   8

Other Resources

Looking for more? 

Some of the OnePetro partner societies have developed subject- specific wikis that may help.


 


PetroWiki was initially created from the seven volume  Petroleum Engineering Handbook (PEH) published by the  Society of Petroleum Engineers (SPE).








The SEG Wiki is a useful collection of information for working geophysicists, educators, and students in the field of geophysics. The initial content has been derived from : Robert E. Sheriff's Encyclopedic Dictionary of Applied Geophysics, fourth edition.

  • Home
  • Journals
  • Conferences
  • Copyright © SPE All rights reserved
  • About us
  • Contact us
  • Help
  • Terms of use
  • Publishers
  • Content Coverage
  • Privacy
  Administration log in