Table of Contents
Electrical tomography can be easily deployed to solve problems other technologies are not suitable for, especially in a case of heterogeneous process conditions:
What is Tomography?
Tomography is the technology that allows us to provide solutions that see inside pipes and separators/tanks, removing doubt from your multiphase flows to cut downtime and optimize your production.
The general idea in tomographic measurements is to expose the target of interest to a physical stimulus, e.g. electromagnetic waves, radiation beam, acoustic waves or electrical signals, and measure the response caused by the target. From the response signals it is possible, with the aid of mathematical models, to infer the distribution of different material within the target. Results of tomographic measurements are displayed as an online cross-sectional or 3D image of the target and indices.
Rocsole’s process imaging solutions are based on a tomographic technology called Electrical Tomography (ET). The basic idea in Electrical Tomographic image construction is to find a permittivity/conductivity distribution for which the observations predicted by the model are in good agreement with actual ET measurement data. See illustration how the principle of Electrical Tomography is applied Rocsole's Pipe and Probe Sensors.
Why Tomography in Oil & Gas?
Rocsole’s solutions are based on Electrical Tomography (ET), which enables whole volume imaging of a process pipe or separator/tank without using a radioactive source. Indices, such as a percentage of free volume in a pipeline with deposition growth, are calculated from the image.
One of the main advantages of the technology is that it can differentiate all the fluid (oil, gas, water) and solid (waxes, scales, hydrates, sand) phases inside pipelines and tanks—even when there is deposition present on the sensor. Using tomographic technology to address flow assurance challenges that have been previously unsolved, Oil & Gas operators can now see and monitor—in real-time—deposition and flow regimes inside pipes and interfaces and the emulsion layer inside separator tanks. From the image, we can crosscheck the accuracy of the indices. Other monitoring technologies—that do not have the benefit of the image—require a blind trust of the index alone.
Read more about our use of tomography in industry articles: Eyes in the Pipe and New Instrumentation Effectively Monitors & Manages Scale and by checking application examples on our application pages.
Tomography versus Nuclear
While safety can be a concern, the cost of ownership is the most significant drawback to nuclear technology. Costs and associated challenges include:
Tomography versus Pressure Loss Monitoring
An increasing loss of pressure in a pipeline due to increasingly constricted flow can be an indicator of solids deposition in the line. The use of pressure loss in a segment of pipeline, however, is poor indication of deposition. First, the loss of pressure, or pressure drop, in multiphase flow can be attributed to a number of causes, such as changes in flow regime, liquid viscosity, gas fraction, water fraction, etc., so an increase in pressure drop doesn’t necessarily point to flow constriction caused by solids. Second, in cases where there has been deposition, we repeatedly see there must be a substantial reduction in flow path cross-sectional area to give a significant pressure drop versus time signature. In essence, as a lagging indicator, monitoring pressure drop in a pipeline is not a very good method to detect solids deposition, except to warn of the final closure of the flow path.
Tomography's Improvement of Fluid Modeling
Modeling to predict solids appearance is widely practiced in some sectors of the industry, but is currently done without deposition measurement data. A fluid model is most often the best indicator—or only indicator—an operator has to predict deposition growth rate. Instrumented pigging or permanent pipe sensor measurement can provide key data to tune and improve models for more effective management strategies. The combination of measurement and modeling is better than either effort alone.
Rocsole: The Tomography Pioneer in Oil & Gas
We are a leading provider of tomography technology for industrial purposes. Established in 2012, and venture-backed by Shell and Repsol, we serve some of the world's largest oil and gas companies, along with other heavy industries.
Excerpt from press release.
Rocsole's Pipe Deposition Scanning Technology Secures Shell Investment
”Rocsole’s smart pig sensor could change the way we inspect subsea pipelines by allowing us to quickly obtain flow and deposition insights using their non-invasive and accurate analytics,” says STV Managing Director Geert van de Wouw. “Their tomographic imaging techniques mean that measurements can be conducted from inside the actual pipe without damaging or disturbing it. Technology that can reduce down time and optimize production is critical for Shell operations, both for on- and offshore.”
Read the full press release.
Harness the Power of Tomography
For Flow Assurance and Process Engineering
Finally, there's a real eye opener. By seeing inside pipes and tanks in real time, Rocsole's systems allow you to overcome tough and costly flow assurance challenges such as deposition and undesired flow regimes in pipes or the emulsion layer in separator tanks. Delivering practical value, our Oil & Gas products offer numerous unmatched benefits with examples of applications showing how each innovative solution has helped overcome real challenges.
By monitoring deposition such as wax, scale and ashphaltenes in pipelines, you can:
Monitor flow regimes such as slugging, water breakthrough and homogeneity in pipelines in order to:
Quantify the actual percentage of sand in your pipeline while monitoring the sand layer in multiphase flow containing gas.
By monitoring your separator tank's emulsion layer thickness and interfaces, you are now able to:
Pipeline Deposition and Tank Content Scanning Services
As the pioneer of tomographic technology in Oil & Gas, Rocsole also offers:
For Instrumentation and Measurement
Rocsole's Tomographic Systems
Designed for demanding industrial conditions, our systems are as useful as they are user-friendly. Convenient features include:
Learn more about Rocsole's sensors and tomographical systems.
For Facilities and Maintenance
Keep your facilities running and minimize downtime with services from Rocsole. Through patented tomographic technology, we deliver the vital information you need to optimize maintenance activities such as pipe and tank cleaning. Facilities and maintenance professionals in the Oil & Gas industry count on big benefits from our innovative services:
Learn more about our Pipeline Deposition Scanning Service.
Learn more about our Tank Content Scanning Service.
For continuous monitoring of deposition, flow regimes and sand in pipelines as well as emulsion and interfaces in separator tanks, Rocsole has pioneered Oil & Gas applications.
For Research and New Application Development
For the first time, you'll now be able to answer the most relevant flow assurance questions. By seeing inside pipes and tanks, Rocsole's systems help Research and New Application Development professionals discover previously unavailable information about the flow, such as variety of flow regimes and deposition growth in pipelines and emulsion in tanks. In addition, our systems provide feedback to flow and deposition models.
Have a process monitoring problem without a solution?
Let us know. Utilizing process visualizing tomographic technology, Rocsole collaborates with customers to develop new applications that deliver real value.
Case Study: Boundary Phase Monitoring Solution
Download the case study to see how we developed a boundary phase monitoring solution that led to zero failures in phase separation during decantation.