When I first started in the oil and gas (and geothermal) industry, there were a few very seasoned co-workers, who were dedicated full time to MEOR (Microbial Enhanced Oil Recovery) and the related biosurfactant generation using microbes. It was aggressively hyped up internally, as well as within the industry. Yet, even as an inexperienced engineer involved in stimulation and chemical applications, I was very skeptical—partly because of the chemistry, and partly because of the personalities involved. I have remained skeptical since, over 40 years later. Actually, it has been more rejection than skepticism.
What is MEOR? MEOR is described this way: MEOR is an in-situ process that produces bacterial bioproducts in the reservoir, either by stimulating the indigenous reservoir microbes with nutrients or injecting beneficial bacteria cultivated from the reservoir. The process involves fermenting biobased products in surface facilities, then injecting them with or without the separation of the microbes. The action mechanisms during MEOR floods are obtained by the presence of microbial metabolites in the reservoir. The useful byproducts include biosurfactants, biopolymers, biosolvents or enzymes that work together in a complex manner to reduce interfacial tension and crude oil viscosity, while increasing rock water wettability and water viscosity. These interfacial processes result in enhanced oil flow to the producing wells (paraphrased from The American Oil & Gas Reporter, April 8, 2024).
MEOR is generally a tertiary recovery method, typically a flooding operation, injecting large volumes to enhance recovery beyond what is possible with secondary waterflooding operations.
I had multiple opportunities, over many years, to recommend MEOR implementation in certain oil fields, following vendor meetings and fairly convincing proposals, but I never did so. It was the same with straight biosurfactant generation, from microbial or nutrient injection treatments. It was not because I did not have an appreciation for, or understanding of, oilfield chemical technologies, including those as complex as MEOR and in situ generation of biosurfactants. And I was not dismissive about chemistry, in general, as are many among industry professionals.
It was just that successful applications seemed ultra-specific to well and field conditions; extensive lab testing was needed to design the appropriate application for any particular case; there were “standard” treatments that were difficult to recommend against, and it was too difficult to get others to buy in, for these same reasons. Also, people just don’t like the thought of microbes or bacteria.
What did at least make more sense to me, with respect to microbial/bacterial processes, were smaller-volume, single-well treatments, such as wellbore clean-up, in which bacteria are injected, generating biosurfactants, as well as biosolvents, to remove oil-based drilling fluid damage or paraffin deposits. The generation of acidic byproducts—along with biosurfactants from bacterial processes—also held some apparent merit for well stimulation applications. But again, while there have been successful applications in certain, very specific cases, there have always been cheaper, more established and more proven standard treatments with much greater track records.
A new age of biosurfactants? What finally does have me interested after all of these years, though, is an intriguing line of biosurfactants—specifically “fermentation-produced’ biosurfactants—such as those provided by Locus Bio-Energy. Before biosurfactants, chemically based, synthesized surfactants have of course had—and continue to have—substantial usage in a wide variety of oilfield applications, especially in well production enhancement and in enhanced oil recovery (EOR).
There are a great many more surfactant applications in many other industries, including the food and beverage industries, cosmetics, medicine, pharmaceuticals, agriculture and mining, among others. Biosurfactants are a specific class of biologically-based surfactants. They are naturally derived, not chemically synthesized. Biosurfactants have been around for a long time, too, but they have historically been more costly than chemically synthesized surfactants, not always readily produced in sufficient quantities and—even with their understood environmental advantages—the higher associated costs to purchase and apply them in the oil field naturally discouraged their use.
Per Locus Bio-Energy, regarding fermentation-produced biosurfactants, specifically: Fermentation-produced biosurfactants offer significant advantages over synthetic surfactants and other bio-based surfactants, including enhanced multi-functional performance, greater environmental compatibility, lower toxicity, greater biodegradability, and longer-lasting activity under extreme conditions of salinity, temperature and pH (paraphrased).
Most importantly to the end-user, the Locus Bio-Energy proprietary methodology can produce customized biosurfactants to address the specific needs of a well requiring treatment, at significantly reduced pricing. An additional attractive quality is that no actual bacteria or nutrients are injected into a well or reservoir—just the end-product biosurfactant, delivered from offsite fermentation manufacturing facilities to the well site.
As Locus Bio-Energy says, “In many ways, it [the biosurfactant manufacturing process] is very similar to how your favorite microbrewery ferments a beer.” That is surely better marketing than promoting microbes.
New uses. Customized biosurfactants can now be used in an even broader range of specific applications, too—not only for the reduction of oil-water interfacial tension, formation wettability alteration, drag reduction and paraffin deposit removal. They also can be manufactured to be small enough to penetrate nanopores and natural fractures in tight and unconventional formations.
Locus Bio-Energy provides custom biosurfactant products for direct injection or as additives in EOR, paraffin removal, acid stimulation, and hydraulic fracturing applications. Products are also manufactured for midstream applications such as in pipelines (drag reduction), saltwater disposal, and cleaning.
More detailed information and success cases can be found at www.locusbioenergy.com.
It’s easy to reject new technologies based on old biases, even if those old biases were valid. But things change, and regarding biosurfactants, I’m willing to change my mind. WO
LKALFAYAN@HESS.COM / Leonard Kalfayan has 42 years of oil, gas and geothermal experience. He has worked for Hess, BJ Services, Unocal and as a consultant. He is an SPE Distinguished Lecturer and Distinguished Member. He has authored numerous publications, and he also holds 13 U.S. patents.