What's new in production

For many in this business, there’s no question about it—offshore is the glamorous star of the global petroleum industry, while land operations—its plainer-looking co-star—are in a supporting role.

Even within land “productions,” there are stars and supporting players. For the moment, at least, shale is the prima donna of terra firma. Playing second banana to the star on this stage is heavy oil.

This is no cameo. Extra-heavy oil accounts for approximately 20% of the world’s petroleum resources, equivalent to about 15 additional years of hydrocarbon reserves. The volume of oil-in-place is estimated to be between 3 trillion and 4 trillion bbl, for potential reserves of around 500 Bbbl. Proved global reserves of conventional oil amount to 1.3 trillion bbl—enough for up to 40 years of supply at the current rate of production. As output from conventional acreage declines at a rate of about 5% per year, global demand is rising. In this environment, extra-heavy oil can play a major role in reserves replacement.

While the spotlight may be on the leading lady, our producers (these Hollywood allusions are hard to resist) are giving the rest of the cast more prominence, even in the face of a few unfavorable reviews. So, while the spotlight shines elsewhere, to further flog the metaphor, it may be informative to drop in on a few studios, where some interesting scripts are in rehearsal.

The heat is on. Heavy oil and SAGD seem as intertwined as movies and sound. But, another promising thermal recovery technique is warming up, so to speak.

That would be electromagnetic heating. The authors lay out the case for it in “Electromagnetic heating: A SAGD alternative strategy to exploit heavy oil reservoirs” (Pasalic, et. al.), a paper prepared for presentation at the World Heavy Oil Congress in Edmonton, Alberta, Canada, this past March, parts of which are summarized here.

Thermal recovery is one of the most important approaches in recovering heavy oil or bitumen. Radio frequency (RF) energy has been considered for downhole heating since the 1970s, without significant commercial success. The underlying scientific premises are sound (and simple), confirmed by basic experiments.

The technology uses an antenna downhole to radiate an RF field into an oil-bearing formation. The electromagnetic energy is dissipated, raising the temperature of the fluids and rock, thus enabling production. We simulate the RF phenomenon, solving the Maxwell equations in tandem with a thermal reservoir simulator. The software does this job by integrating the reservoir simulation code and advanced EM simulators.

Study cases suggest that RF heating could produce similar volumes of heavy oil, in similar periods of time, as SAGD. The main application of this technology is heavy oil/bitumen reservoirs, where steam injection is difficult to apply or not applicable (thin or shallow reservoirs, reservoirs with poor cap rock, etc). This technology could save important volumes of water and reduce CO₂ emissions, when compared to SAGD.

The authors point out that the main advantage of RF heating technology, compared with other electrical heating processes, is that the RF process heats the reservoir volumetrically, while the heater relies only on conduction to propagate heat through the reservoir. They also note that in many cases, RF heating technology will need to be applied, together with another process, for pressure support. Heating, alone, may not be sufficient to produce oil at commercial rates. For a design similar to a SAGD process, gas injection seems to work effectively and could be cheaper than other fluid injection.

Jet transportation. According to Canadian company Fractal Systems, asphaltenes are the heaviest and most polar fraction of oil. They tend to agglomerate or overlap. In crude oil, they are surrounded by a sea of maltenes. The spatial organization of maltenes and asphaltenes results in the macro and micro structural properties, with the macromolecular organization causing the high viscosities.

Rather than breaking the larger molecule structures by thermal action (leading to de-alkylation, cracking and coke formation), the company uses a hybrid approach. Thermal disorder is first introduced, and through a combination of solvation, high shear forces, and near-sonic velocities, kinetic energy is transformed into chemical energy. The consequence is that the oil is structurally modified. These reactions are carried through well-engineered, orifice-restricted jet nozzles. Other parts of the process are proven, “off-the-shelf” equipment, such as high-pressure, positive displacement pumps and heat exchangers.

The company says its Jetshear technology can dramatically reduce the amount of diluent required to transport heavy oil to market. It can be applied in a thermal operation, where it may displace a trim blending facility, and can also be placed in a midstream operation to improve the efficiency of blending operations.

A recent demonstration of this technology for transporting heavy oil or bitumen through pipelines shows promise. In the demonstration, a 1,000-bpd facility operated for approximately one year. During this period, the facility processed over 100,000 bbl of partially diluted bitumen.

The goal of the project was to: 1) meet processing objectives with commercial-sized nozzles; 2) achieve desired nozzle life performance; 3) meet facility operability and throughput expectations with no safety or environmental incidents; and 4) achieve certain product quality targets (product stability, H₂S content, acidity, and liquid yield). All key targets were met or exceeded, and the demonstration was deemed a success by the partnership.

Bravo. Both of these performances are worthy of praise by the critics. And, other talented players are surely waiting in the wings, waiting for a chance to star.