How bacteria might boost oil recovery
It sounds as unlikely as Jed Clampett shooting the ground and watching ''Texas tea'' gurgle to the surface: pour microscopic bugs down an oil well to boost the amount of crude that can be drawn out.
The idea, affectionately called microbial-enhanced oil recovery (MEOR), has been pursued without much success since the 1940s. But interest in the technology has blossomed in recent years as the hunt for energy sends scientists into more remote corners of the globe and lab.
The technique won't break the United States free of the Mideast petro-sheikhs. Indeed, some doubt it will work at all. But researchers expect to soon put some strains of bacteria to work in the oil patch to help breathe new life into old fields.
''There is tremendous potential for using bacteria in oil production and transportation,'' says Dr. Erle Donaldson, head of geoscience research at the Department of Energy (DOE).
With MEOR, scientists are not trying to alter the genetic nature of bacteria. Instead, they are searching for microbes that already have the desired capabilities. That means ''superbugs'' that can survive the rigors of a subterranean oil tomb and create the right chemicals and gases to force more petroleum to the surface. So far, no commercial brews exist in any abundance.
But scientists at companies and universities are isolating potentially useful bacteria. At Illinois-based Petrogen Inc., for instance, researchers are trying to develop bugs that will eat waxes and paraffins, leaving behind a thinner crude, easier to extract and transport.
Petroleum Bioresources Inc., a Texas firm, will test two types of microbes at wells in Colorado later this month. The hope is that the organisms will create ''soapy'' chemicals to wash oil out of tight cubbyholes in the reservoir. Another aim: that by producing acids and certain gases, the bugs will lower the viscosity of the crude and push more of it above ground.
Other options are being explored at four universities around the country, backed by DOE. A team from the University of Oklahoma, for instance, thinks it has found strains that could plug pores in rock. This would force more of the oil toward the producing well.
There is hope still other microbes will devour pollution-creating sulfur in the crude while it is still in the ground. Canadian researchers want to put bugs to work to tap the country's vast tar sands. ''We should see a proven technology within 11/2 to 2 years,'' predicts James Zajic, president of Petroleum Bioresources.
If any of these efforts do move from the idea shop to the marketplace, there will be plenty of interest. Billions of gallons of oil remain in played-out reservoirs in the US alone. Conventional production techniques typically tap less than half of a field's oil. Enhanced recovery techniques, such as steam or gas injection, can glean another 10 to 15 percent.
Scientists hope to improve on that with ''miracle'' microbes. ''It is not the answer for all enhanced oil recovery,'' cautions Dr. J. Bennett Clark, senior research microbiologist at the Phillips Petroleum Company. But, he adds, fossil fuel is a finite source of energy and eventually companies are going to have to use such technologies.
Still, a tankerful of snags remains. Not the least of them is finding organisms that can withstand the heat, pressure, and briny conditions in deep wells. Then, too, there is no guarantee that the microbes will not multiply and latch onto the walls of the reservoir, sealing it off.
The oil industry, for its part, holds mixed views of the technology. Some firms are actively pursuing microbial research in laboratories. Others have adopted a wait-and-see approach, and a third group remains altogether dubious about its potential.
''The general approach of genetically engineering organisms and putting them down an oil well is not going to pay off this century,'' says John Sibert, Atlantic Richfield's exploratory research manager. But, he adds, biotechnology may be used within the next few years (at the surface) to produce better chemicals for use in conventional enhanced oil-recovery techniques.