Foam Favorable for Oil Extraction Over Water

Rice University Researchers Demonstrate That Foam may be a Superior Fluid to Extract Oil than common Techniques Involving Water

Foam Floods In Micromodels - See Video

A Rice University laboratory has provided proof that foam may be the right stuff to maximize enhanced oil recovery (EOR).

In tests, foam pumped into an experimental rig that mimicked the flow paths deep underground proved better at removing oil from formations with low permeability than common techniques involving water, gas, surfactants or combinations of the three.

The open-access paper led by Rice scientists Sibani Lisa Biswal and George Hirasaki was published online today by the Royal Society of Chemistry journalLab on a Chip.

Oil rarely sits in a pool underground waiting to be pumped out to energy-hungry surface dwellers. Often, it lives in formations of rock and sand and hides in small cracks and crevices that have proved devilishly difficult to tap. Drillers pump various substances downhole to loosen and either push or carry oil to the surface.

Biswal's lab haslearned a great deal about how foam forms. Now, with an eye toward EOR, she and her colleagues created microfluidic models of formations — they look something like children's ant farms — to see how well foam stacks up against other materials in removing as much oil as possible.

The formations are not much bigger than a postage stamp and include wide channels, large cracks and small cracks. By pushing various fluids, including foam, into test formations, the researchers can visualize the ways by which foam is able to remove oil from hard-to-reach places. They can also measure the fluid's pressure gradient to see how it changes as it navigates the landscape.

The team determined the numbers are strongly in foam's favor. Foam dislodged all but 25.1 percent of oil from low-permeability regions after four minutes of pushing it through a test rig, versus 53 percent for water and gas and 98.3 percent for water flooding; this demonstrated efficient use of injected fluid with foam to recover oil.

The less-viscous fluids appear to displace oil in high-permeability regions while blowing right by the smaller cracks that retain their treasure. But foam offers mobility control, which means a higher resistance to flow near large pores.

Source: Rice University

Read More Related Content On This Topic -Click Here

Media

Taxonomy

• Job Function
• Research