Advances in drilling and well stimulation technology continue to be made in oil and gas wells across North America with the purpose of increasing production and improving cost-effectiveness of operations. However, as the quest for new wells stretches farther into uncharted territory, a significant portion of new wells are sited in increasingly remote areas, sometimes at great distances from the existing pipeline structure. A side effect is that, due to the inaccessibility of well sites, excess produced gas must be flared.

GE Oil & Gas’ “CNG In A Box” system allows E&P companies to use and monetize more of their produced gas, even at wells in inaccessible off-grid locations. The first stage of the development of the CNG In A Box system was directed to natural gas vehicle (NGV) refueling, but with a few simple improvements, it turned out to be well suited to “virtual pipeline” applications.

Creating a virtual pipeline

The CNG In A Box system is a virtual pipeline product that aims to help move beyond the physical pipeline network with a modular “plug-and-play” CNG solution when combined with trucks to move gas vs. a traditional pipeline system. This helps operators improve availability, access more customers and monetize their flare gas.

The system delivers exceptional availability and efficiency ensuring continuous, reliable unmanned operation; long intervals between maintenance; and an easy, cost-effective maintenance regimen. The H series high-speed compressor is a reliable proven frame with thousands of hours in the field and a wide install base.

CNG In A Box performance equates to 4,000 gal to 20,000 gal of gasoil equivalent per day for virtual pipelines. It features a portable design, minimal pad, quick installation and highly automated operation. It is ideally suited for rig-site gas distribution, flare capture and storage on remote sites.

The same technology can be used to flare gas, enable onsite power generation and be suited for on-road transportation fueling of NGVs because of the modularity and flexibility of the design.

Developing a fueling technology

GE Oil & Gas has taken its CNG In A Box technology and partnered with Ferus Natural Gas Fuels to provide a reliable, fully integrated natural gas fueling option for some of Ferus’ E&P customers. Where GE Oil & Gas specialized in providing natural gas fueling technologies such as the CNG In A Box system, Ferus specialized in fuel supply, transport and logistics, including the dispensing of fuel onsite, pressure reduction and vaporization solutions.

Together the companies built a fueling technology, eliminating the need for flaring, and instead captured the flare gas and delivered it straight to fueling applications. This fully integrated technology and logistics system was designed to make natural gas fueling available for high-horsepower operations. It did this by taking previously uneconomic natural gas directly from a wellhead or oilfield production site or from a remote pipeline, removing the impurities, compressing it with a CNG In A Box system and delivering the CNG with Ferus’ tankers the final distance to a drilling location to be consumed as fuel, displacing diesel. The aim was to allow cleaner, cheaper fueling, which is economical in the most remote areas for E&P operations while reducing environmental impact.

Working together

The fuel technology was designed to provide customers with a fit-for-purpose turnkey natural gas fuel solution; therefore, early engagement with operator stakeholders was vital to commercial success. First, the process of developing the technology involved developing an operations overview that looked at the priority of the asset and formation, the rig schedule, and the gas source and composition. Second, a fueling strategy was developed that considered fuel selection and aligned clients’ needs with Ferus’ and GE Oil & Gas’ product offerings. Finally, an implementation plan was drawn up that includes the deployment strategy and a logistics plan.

The method

Gas supply at about 1 MMscf/d to 2 MMscf/d during a four-month to 12-month period bypasses flaring and was taken straight to the gas treatment stage. It was then converted to NGL and CNG. These products were then used in gas transport applications, with NGL storage and transport being a locally marketed product and CNG destined for rig and frack fuel as a gas-lift primer and for third-party sales.

The CNG In A Box package was provided with a 400- hp H304 compressor using four throws. While the fourstage unit used was well-suited, it could have been even better for virtual pipeline if it had been configured as a two-stage unit, which was an option.

The package featured onboard priority panel, dryer, cooler and programmable logic controller/human machine interface with remote monitoring and diagnostics capability to support fast commissioning at remote locations. The CNG In A Box technology, however, is flexible and can be provided with a variety of compressors from 100 hp to 400 hp using two or four throws. Much of the onboard equipment is optional, allowing a solution that can be optimized for turnkey remote virtual pipeline locations to less demanding NGV refueling applications. In any case, the CNG In A Box features are designed to simplify and expedite installation for their operators.

The virtual pipeline technology is used by several oil producers in the Bakken, with plans to expand beyond the Bakken into other basins in North America.

Case study

In early 2014 the Ferus/GE Oil & Gas partnership conducted a successful virtual pipeline pilot with Statoil to capture flare gas and use it as an alternative fuel to diesel to power its oilfield operations.

The fueling technology initially captured 2 MMscf/d of natural gas for Statoil, and the number had capacity to grow to 6 MMscf/d. This translates to total emission reductions of 70,000 tons/year, or the equivalent of 17,500 cars in a year. Statoil will use 500 MMscf/year of its own captured natural gas to fuel its operations. When used in place of diesel, it equates to an additional 18,000 tons/year of smog reduction and 4 tons/year of particulate matter reduction.

From an economic perspective this results in $6 million in fuel cost savings. The remainder of the captured natural gas from Statoil’s oil and gas operations will be compressed and sold to third parties either in oil and gas or other high-horsepower markets.

In this case, the virtual pipeline technology enabled Statoil to tackle the challenges related to the lack of pipeline capacity and mobility issues surrounding flaring in the Bakken. As a result of the success of the pilot, the parties are moving into the commercial phase, which involves fueling up to six rigs with natural gas that would have otherwise been flared. The project expansion will be the first step in moving into full commercial adoption of the virtual pipeline technology.

E&P companies can use the CNG In A Box system as part of a virtual pipeline technology to remain compliant with stringent gas flaring standards. Companies also can reduce their emissions profile by eliminating flaring and using the previously wasted natural gas as an alternative fuel to diesel in their drilling and completions operations. This technology can reduce natural gas flaring in North Dakota by 1.6 MMcm/d (60 MMcf/d), or 20%, and has the potential to play a critical role in flare gas reduction in wells beyond the Bakken, including expanding gas processing capability and powering production.