The recent revolution in the production of oil and gas from shale formations has led to a new era of energy prosperity and energy security in North America. However, the primary technology utilized today for shale production -- hydraulic fracturing -- is under heavy scrutiny and potential political/regulatory risk, primarily because it utilizes large volumes of water; injects chemicals into underground formations that some deem to be dangerous; requires treating and disposing large volumes of fracturing wastewater; and requires a very large number of water/wastewater truck trips per well.
Expansion Energy determined that the use of water is at the root of the main problems/threats associated with hydraulic fracturing, and therefore embarked on a path of innovation to develop a fracturing technology that eliminates the use of water and chemical additives while lowering total costs, maintaining or increasing well productivity, and enabling a range of additional benefits.
The outcome of this endeavor is our patented "VRGE(TM)" (pronounced "VeRGE") "dry fracturing" technology (US Patent # 8,342,246) -- available for license. Instead of water, VRGE utilizes cryogenically processed natural gas from nearby wells or from the targeted hydrocarbon formation itself as the fracturing medium and as part of a proprietary, non-toxic proppant-delivery system.
In addition to its applications for fracturing new wells, VRGE can also be used for recompletions, lifting or enhanced oil recovery (EOR).
VRGE creates "CCNG(TM)" (cold compressed natural gas) at the well site, ideally by using Expansion Energy's "VX Cycle" small-scale LNG/CCNG technology. Expansion Energy refers to the CCNG as "Metacritical(TM)" phase natural gas. The Metacritical(TM) NG (CCNG) is then pumped to high pressure before expanding it into high-pressure CNG and blending it with a proprietary, foam-based proppant delivery system. (Pumping a quasi-liquid like CCNG requires far less energy than compressing a gas.) This "gas-energized" fluid is then sent down-hole where it fractures the formation and holds open the fissures in the formation with proppant delivered by the foam system. "Energized" fracturing fluids (such as those using CO2 or nitrogen) have been shown to increase well production.
Most of the chemicals used in standard hydraulic fracturing are necessary to mitigate the negative impacts of water on the targeted hydrocarbon-bearing formation. Water "swells" the formation and creates surface tension, both of which inhibit the flow of oil & gas. In contrast, VRGE does not require these chemical additives because VRGE requires no water.
Importantly, natural gas used by VRGE for fracturing eventually resurfaces and can be sold to the market or used for additional VRGE fracturing. As a result, there is no economic loss from using natural gas as the fracturing medium.
Utilization of the VRGE approach does not require any changes to the pre-fracturing stages of a well's development -- i.e., the drilling and perforation of the well bore -- which are conducted exactly the same as for today's hydraulically fractured wells. Moreover, after VRGE completes the fracturing of the formation, the well can be operated just like today's hydraulically fractured wells.
After fracturing is complete, the CCNG plant (e.g., VX Cycle) can either be moved to the next well site for fracturing or it can remain at the original well site to produce LNG for the market on an ongoing basis. Additionally, the deep refrigeration of the CCNG plant can be used to extract natural gas liquids (NGLs) -- such as propane, butane and ethane -- from the gas stream. The CCNG plant can also be used to capture associated gas from oil wells that would otherwise be flared, and convert that gas into LNG for easier transport to market.
For a detailed overview of the VRGE waterless fracturing technology and its many advantages, please download the VRGE PowerPoint presentation provided below.
VRGE In the News
Expansion Energy is actively seeking licensees, co-marketers and demonstration opportunities for its VRGE Waterless Fracturing technology. Interested parties are invited to contact us for discussions.