Since the horizontal well boom began, production technology has advanced exponentially. But despite these advances, there remains an arduous and persistent problem which plagues both conventional and unconventional wells alike — paraffin and scale buildup.
Treating paraffin with Magnetic Fluid Conditioning
Magnetic Fluid Conditioning (MFC) is not new to the oilfield. Historically, though, the process hasn’t been trusted as an effective paraffin treatment method due to design flaws, often a result of inadequate engineering. While MFC treatments have been utilized on conventional vertical wells with great success, the technology has yet to become common practice when treating horizontal wells, which produce inherently higher volumes of oil, gas and water.
In recent months, Pioneer Natural Resources and Energy & Exploration Partners Operating LP (ENXP) each chose a horizontal well to run trials with Flo-Rite MFCs installed downhole. Before the MFC trial began, both the Pioneer well, located in the Permian Basin, and the ENXP well, located in the Eagleford, required hot-oil/watering every two to three weeks due to paraffin buildup.
After installation of the MFCs, the buildup in the flowlines was inspected in two week intervals. After 10 weeks, the downhole MFCs indicated success, and inspections showed the tools on both wells not only prevented further buildup, but removed accumulated paraffin, eliminating the need for routine hot oil treatment.
Selecting the right MFC for your well
Not all MFCs are created equal. Following an intensive re-engineering phase and frequent updates, Flo-Rite received several U.S. Patents for its unique and varied designs. When choosing which MFC to install on a horizontal well, there are several key differentiators to consider when selecting the tool best suited for wells with persistent paraffin buildup.
Size and shape
For magnetic fluid conditioning to be effective, the mixture of hydrocarbons and water flowing to the surface must pass through the tool at a specific velocity. If the annulus of the tool isn’t sized properly, the magnetic forces acting on the fluid passing through the MFC aren’t as strong, resulting in lower cloud points and higher crystallization rates.
Also, not all shapes are created equal, especially when fluid conductivity and electro-hydrodynamics are taken into account. During the redesign phase of Flo-Rite’s MFC technology, the team discovered that by flowing the fluid through a precisely-sized annulus and into a rectangular structure, the molecules passed through the MFC’s alternating magnetic fields at right angles. When compared to tools using circular structures, the rectangular shape ensures that the magnetic forces properly interact with the dipolar nature of the fluid passing through the device.
In-line vs. clamp-on
Clamp-on MFC tools on the market are designed to clamp onto the outside of existing flowlines on a producing well. Clamp-on MFCs are ineffective because they only have a single magnetic field and the distance separating the north and south poles create a force that is too weak to exert its polarizing and stabilizing effect on the molecules traveling through the tool. The clamp-on MFC’s exert most of their magnetic strength onto the ferritic carbon steel of the flowline which treats only the surface the device is attached to, not the production.
Flo-Rite’s in-line design allows the production to travel through an inner annulus where the magnetic strength is at its highest. Directing the path through this inner annulus exposes 100 percent of the fluid to the strongest part of the magnetic poles, allowing every drop to be treated.
Paraffin buildup only becomes an issue when hydrocarbon fluids begin their journey to the surface. As temperature decreases while the forces of friction and pressure change, particulate matter such as paraffin and asphaltenes begin to crystallize and accumulate. Installing an MFC downhole and in-line with production flow ensures that the tool exerts its attractive force on 100 percent of the fluid passing through the MFC prior to the cloud point and crystallization.
Additionally, by placing an MFC downhole, remedial paraffin control methods such as chemical treatments are required less often, resulting in lower operating costs. Placing the tool downhole alleviates the need for other frequent treatments such as hot-oiling and wire-line paraffin cutting, which can ultimately damage and compromise the integrity of a horizontal well’s cement.
The engineering team found that most existing MFCs used in the oil and gas market were constructed using ferritic carbon-steel. This type of steel, while common and inexpensive, absorbs most of the magnetic field and doesn’t allow the full strength of the magnetic force to be applied to the fluid passing through the tool.
Stainless steel was deemed necessary by Flo-Rite because of its molecular structure and high chromium content. This composition provides strength, is corrosion resistant, and is more conductive and better able to transfer the higher energy magnetic force required for effective fluid treatment.
Types of magnets used
Much like the difference between using stainless steel instead of carbon steel, the type of magnets used in an MFC are a good indicator of how effective a tool will be. By utilizing powerful rare-earth magnets the MFC is guaranteed to exert the Lorentz Force on every drop of the fluid passing through the tool.
But, like the difference between a rectangular and a round design, the configuration of these strong, permanent magnets is paramount for proper treatment. The Flo-Rite team found that by strategically placing an array of these magnets so the magnetic currents alternate as fluid moves through the device, the dipolar molecules are run through a series of magnetic fields. Once passing through these alternating fields, the molecules are properly polarized, forcing the once chaotic movement of fluid into a more lattice like molecular structure, preventing the accumulation of unwanted particulate matter by minimizing the size of crystallization points.
Money Saving Guarantee – The Flo-Rite 30-day trial
Although MFC technology is not new to the oilfield, the Flo-Rite team recognizes that not all products, and not all treatments, are created equal. Sourced from decades of experience treating paraffin buildup in conventional vertical wells, Flo-Rite is seeking to bring MFC technology to the forefront of the unconventional world of horizontal well producing.
As a display of confidence, the Flo-Rite team encourages you to test their devices for free. To witness the cost saving results firsthand, and for more information about Flo-Rite’s 30 day free trial offer, visit the Flo-Rite website or contact Flo-Rite Fluids Inc. by phone at 325-893-0069, or by email at firstname.lastname@example.org.