Measurement Library

North Sea Flow Measurement Workshop Publications (2017)

The Search for Gas Chromatograph Operational Nirvana
Author(s): Anwar Sutan Brge Olafsen Andrew Runcie
Abstract/Introduction:
In the summer of 2017, the author went for a holiday with his family and was lucky to stay in a hotel which got to be pretty close, in authors notion, to what is often called a Nirvana. It was not only because the whole complex was amazingly beautiful and the tropical Island itself was gorgeous, but mainly because of the feelings experienced by guests when they see what happened around them when some imperfections or nuisances occurred. Responses of the hotel staff to all emerging shortcomings were practically instant. All hotel employees have been seemingly trained to immediately spot weak issues: they just know when wet towels are to be replaced, empty glasses to be filled, rooms to be tidied, etc. If the guests looked a bit confused, the help was there at once as if the crew can read the guests minds and were ready, just like angels, to fulfil every need of each hotel guest.
Go to Download Page
Email Reference
Document ID: 353B66A3

Flare header gas sampler at atmospheric pressure
Author(s): Ole-John Melkevik
Abstract/Introduction:
At Karst we do have 5 flare stacks. Into these flare headers there are 7 ultrasonic flaremeters. The Government Norwegian Environment Agency demand that there must be documented whats on the inside of the flare lines. It is accepted to take spot samples once a month to verify that the meters are operating correctly. Therefore, there is a need for a reliable sample system to get the spot sample out of the flare header without contaminating it with air or any other unwanted components. Also have a working environment that is acceptable 2017. When having a permanent sampling system the quality of the sample will also have reduced uncertainty. In addition the sampling will be done faster which means that one will save time.
Go to Download Page
Email Reference
Document ID: 883077FB

Instrument Performance Evaluation, comparing ISO 10723 and NORSOK I-106
Author(s): Paul Holland
Abstract/Introduction:
Overview of presentation Importance of the GC and its performance Importance of a good quality calibration gas Introduce Norsok I-106 test & ISO 10723 and highlight different evaluation approaches Highlight some of the additional benefits from the ISO approach Results of using an ISO 10723 to generate a Norsok test report Summary
Go to Download Page
Email Reference
Document ID: 2AE0C9B1

Joining efforts between operators within multiphase metering technology
Author(s): Eirik bro Jean Paul Couput Rick de Leeuw
Abstract/Introduction:
For many years, operators have been using various multiphase and wet gas metering techniques. One of the reasons for implementing multiphase metering solutions were to develop subsea tie-ins, achieve cost reduction and to improve production optimization. More recently the discussion arose that some joint efforts would be valuable in which the operators would share and discuss experiences and needs combine efforts to improve multiphase and wet gas flow measurement. The idea to share some information between users was more recently discussed in conferences like the NSFMW. A first meeting was organized during the NSFMW 2015 in Norway between several operators to discuss about needs, technology status and standardization.
Go to Download Page
Email Reference
Document ID: 22A3A735

New Generation Vibrating Tube Sensor for Density Measurement under Process Conditions
Author(s): Alfred Rieder Paul Ceglia
Abstract/Introduction:
Density is one of the most prominent means to classify the physical properties of crude oil and refined products and as such, accurate density measurement has significant importance and value to the hydrocarbon processing industry. Continuous density measurement is used in the determination of quantities for custody transfer and allocation measurements, inventory control, product quality control, blending applications as well as interface detection. The most stringent density performance requirements for accuracy, repeatability, linearity and reproducibility are normally found in custody transfer applications and those applications impacting financial reporting or taxation. Custody transfer systems require both a density and a volume or mass component of sufficient accuracy to determine fiscal quantities. Furthermore, determination of quantities by inferred mass, where metering is done on a volumetric basis but reporting is in mass terms, require the lowest density uncertainties due to the direct first order effect of the density measurement uncertainty to the overall uncertainty of the reported quantity.
Go to Download Page
Email Reference
Document ID: CD33C7E0

Fiscal Metering Systems Mismeasurement Management Experiences in Petronas
Author(s): Wan Adrie Wan Ahmad Han van Dal
Abstract/Introduction:
Mismeasurement management is about the detection and correction of systematic measurement errors in hydrocarbon quantities reported by a custody transfer flow metering system. A systematic (deterministic) error is due to an assignable cause, such as a transmitter failure, a disturbed meter pulse signal, a faulty parameter value or a measurement that fails its validation. This opposed to a non-deterministic error which is caused by natural variance. The correction of a measurement error is not an obvious task and requires in-depth analysis of all available information to determine an accurate substitution for the faulty value. A poor correction could increase the error instead of rectifying it. A separate correction is required for every associated transaction, e g. a transmitter failing its quarterly validation may require the correction of dozens of daily reports.
Go to Download Page
Email Reference
Document ID: 055673CE

Evaluation of Sampler with integrated zero leakage valve on Aker BP ULA platform
Author(s): E. Verloop M.Sc. P. Verloop M.Sc. E. Sveinsvoll S. vreb
Abstract/Introduction:
Automatic Sampling is one of the measurement methods most used to determine the quality of crude oil and condensate feeds, i.e. the water content and crude composition. As with all moving parts, automatic samplers are subject to wear. Especially in the cases of maturing production fields or locations where sand in combination with high pressure can be present, premature leaking of the sampler can occur. A new sampling design containing an innovative zero-leakage-valve was found to cope with these harsh environments. The new sampling technology was tested on multiple locations e.g. on Oselvar tie in to Ula and on Valhall export oil and compared by Aker BP to traditional sampling designs from different brands not having a zero-leakage-valve. Tests were performed on different crude oil/water mixtures.
Go to Download Page
Email Reference
Document ID: A5F67DF5

Lies, Damned Lies, and the Statistics of Data Fitting
Author(s): Richard Steven Eric Harman Terry Cousins
Abstract/Introduction:
A core requirement for achieving low uncertainty flow metering is that each step of the quality control process has integrity and is rigorously adhered to. Calibration is a critical part of many flow meter quality control procedures. The calibration process consists not only of testing the flow meter at a reputable flow laboratory across the appropriate flow conditions, but also of how that recorded data is subsequently implemented into the flow metering systems calculation routine. This second part of the calibration process, often called linearization, curve fitting, or data fitting, is a critical part of flow meter quality control. There are multiple ways of linearizing a flow meter, and yet, few meter manufacturers, end users, standards boards, or regulators have stated comprehensive published rules regarding this process.
Go to Download Page
Email Reference
Document ID: 5F50CCE9

INSTALLATION EFFECTS UFM, SKID CALIBRATION, NONSENSE OR NECESSITY?
Author(s): Marcel Vermeulen Dave van Woensel Sacco Tange Jan Drenthen
Abstract/Introduction:
It is common practice to calibrate custody transfer ultrasonic gas flowmeters with dedicated upstream piping and, in a more conservative approach also with a flow conditioner. Argument is this will create repeatable circumstances, meaning the flow profile in the field will be identical to the one seen during calibration. In recent years this approach has been complemented by a new generation of ultrasonic flowmeters that have reported to possess a very limited impact on measurement uncertainty in case of flow profile variations during, for example, OIML R137 disturbance tests. Despite these arguments a discussion is ongoing whether it makes sense to calibrate entire Z-configuration measurement skids instead of only meters. Thought behind this is it will make the flow profile even more repeatable which could further reduce the measurement uncertainty. To conclude this discussion KROHNE calibrated multiple Z-configuration skids.
Go to Download Page
Email Reference
Document ID: 7E833F5A

Experiences with Permanent Series Connection of Ultrasonic Gas Flow Meters (USM) in the German Gas Market
Author(s): Daniel Heinig Toralf Dietz Jrg Wenzel Claus Girschik
Abstract/Introduction:
In recent years, the benefits of ultrasonic flow meter technology, especially the low pressure drop and diagnostic capabilities, were the driving force to allow series connections of two USM. The series connection of two independent USMs is now the favored solution in many metering stations in Germany. In 2013, the Physikalisch Technische Bundesanstalt (PTB) consolidated end users experience with connecting USMs in series into the technical guidelines TR-G 18 Requirement for permanent series connection of two ultrasonic gas flow meters. This paper offers an overview of typical USM-USM setups and discusses experiences of recent years.
Go to Download Page
Email Reference
Document ID: 4FDF9F05

Turbulence Profile Effects on the Accuracy of Ultrasonic Meters
Author(s): Eric Harman
Abstract/Introduction:
By rotating an upstream flow conditioning plate, an USMs meter factor can shift producing a measurement error. USM meter factor shifts were compared to a theoretical turbulence intensity model of the upstream flow conditioning plate suggesting a correlation. USM meter factor shifts were corrected for using a turbulence correction factor based on turbulent sinuosity.
Go to Download Page
Email Reference
Document ID: C69D8530

The revision of ISO 6976 and assessment of the impacts of changes in this standard on the natural gas industry
Author(s): David Lander Tony Humphreys
Abstract/Introduction:
The natural gas industry is large in 2016 worldwide natural gas consumption was some 24 % of total energy consumption and its production amounted to 3542 bcm (BP, 2017). Accurate determination of energy flows of natural gas is therefore very important to all stakeholders in the natural gas industry and ISO 6976 (Natural gas - Calculation of calorific values, density, relative density and Wobbe indices from composition) is an extensively employed standard. It is widely used to determine calorific value of natural gas and hence to compute the amount of energy traded or consumed. It is therefore a reference standard for many natural gas sales contracts and is critical to gas consumer billing in many countries. In addition to calorific value, ISO 6976 is also employed to calculate other important properties of natural gas, such as Wobbe index - a critical property when considering safe operation of natural gas appliances.
Go to Download Page
Email Reference
Document ID: D99DAC67

Oil & Gas - How to do sustainable business
Author(s): Espen Norheim
Abstract/Introduction:
Norway has a significant trade surplus compared to other countries -both in absolutely terms and in terms of population ?Oil exporting countries create noticeable trade surpluses, e.g. Saudi Arabia, Qatar, Brunei and Kuwait
Go to Download Page
Email Reference
Document ID: 1D959634

Conversion of a large scale orifice measurement station to an ultrasonic measurement station with double capacity
Author(s): Steinar Fosse Frode Bjelland G?nter Buss Rainer Kramer
Abstract/Introduction:
The Ekofisk Field was discovered by Phillips Petroleum Company in 1969. It is located offshore in the southern sector of the Norwegian Continental Shelf. The development of the field started soon after and first oil was tanker loaded on the field in 1971. The permanent oil pipeline (354 km, 34) to Teesside in United Kingdom (UK) was ready for operation in 1975. The permanent gas pipeline (443 km, 36) to Emden in Germany was ready for operation in 1977. See figure 1. Pipeline infrastructure, underneath.
Go to Download Page
Email Reference
Document ID: 860BB946

The Case for Integrated Process Simulations in Allocation Systems
Author(s): Amy Ross Phillip Stockton
Abstract/Introduction:
This paper discusses and makes the case for the use of integrated process simulation models in hydrocarbon allocation systems used by upstream and midstream hydrocarbon processing facilities such as offshore installations and onshore gas plants and oil terminals. The main purpose of simulation models within hydrocarbon allocation systems is to provide information relating to the behaviour of hydrocarbons in a process plant. The use of simulation models ranges from the generation of process information e.g. shrinkage factors, to full integration of the model within the allocation process itself. In the remainder of the paper the outputs from process simulations used in allocation systems have been generically termed process factors. The simualtion model is intended to reflect the changing operating conditions, flow rates and variations in composition experienced in the process, expressed in terms of the process factors.
Go to Download Page
Email Reference
Document ID: 4EF123E8

Lundin Edvard Grieg and Brynhild - Implementation of Topside and Subsea Multiphase Meters, Collaboration for Success
Author(s): Geir Kristensen Sren Forne
Abstract/Introduction:
The purpose of this paper is to provide a practical example for how maximum performance in operation of a multiphase metering system can be achieved. This is demonstrated by describing the ongoing collaboration between Lundin and Emerson/Roxar, and by analysing how this collaboration model works in the follow up of Roxar multiphase meters (MPFM) installed at Brynhild and Edvard Grieg fields in the North Sea. Brief descriptions of the application, and of the applied measurement technology, will be provided as background for the reader, the focus of this paper will be on the collaboration model. We will look at how this cooperation optimises the meter performance and return on investments? Are opportunities for improvements uncovered during the period of cooperation? What are the main benefits for the involved parties?
Go to Download Page
Email Reference
Document ID: E4D06871

Possible installation effects on density meter in a fast loop sampling system.
Author(s): Skule E. Smrgrav Nils Petter Aarstad Steve Watson Gabriel
Abstract/Introduction:
During assembly and testing of a fast loop system we observed readings from the density meters with periodic anomalies. Further examinations were executed on different fast loop systems to collect necessary information for a study of possible installation effects on a density meter in a fast loop system. Tests were initially performed on existing fast loop systems, and later on a test installation consisting of a density meter and an intrusion device which simulates a generic grab sampling device penetrating the fast loop while performing a grab. This test setup will be discussed in more detail and the test results will be explained.
Go to Download Page
Email Reference
Document ID: 7BCB6B9A

Master meter proving with helical blade turbine meter
Author(s): Didier Pabois
Abstract/Introduction:
no paper submitted
Go to Download Page
Email Reference
Document ID: DFF8F741

Flow Testing of a New Method for Formation Water
Author(s): Andrew Baker Harold Solheim Rolf Rustad Alexandre Lipeau
Abstract/Introduction:
Measurement of water flow rate and MEG dosage are often key issues for subsea wet gas wells and distingushing between formation water and condensed water is an important factor.
Go to Download Page
Email Reference
Document ID: BB2CA962

Field Use of a Composite Phase Fraction Meter
Author(s): Alan Parker
Abstract/Introduction:
M-Flow Technologies have developed a phase fraction meter for oil and gas applications based on a unique carbon fibre reinforced thermoplastic pipe technology. The phase fractions measured are the volumetric fractions of oil, water and gas in 3 phase fluids and the volumetric fraction of water in a 2 phase mixture of water in oil. Composite construction allows the sensor elements to lie outside of the flow path, without obstruction or contact with the flow line fluids, and the sensing is capable of measuring the full flow line diameter. This gives significant advantages in terms of meter reliability and performance compared with conventional meter designs. The sensor device is monolithic, suitable for high line pressures and has good sour service performance as standard.
Go to Download Page
Email Reference
Document ID: 4A446722

Field performance evaluation of a non-radioactive MPFM in challenging conditions in the Middle East
Author(s): Hugo Harstad Hamza Fahd Matallah Audun Aspelund Ahcene Nasri Emad Safar Ahmed Aburghiba Fatma Al Hazeem Mouzah Al Khatrash Bohlool Asgar Ali Fateh Samai Antranik Khokazian
Abstract/Introduction:
Production testing using mobile test separators and multiphase flow meters (MPFM) are widely used in KOC, Kuwait. The utilization of multiphase flow meter technology for monitoring well streams can be a supplement to, or in some cases replacement for traditional testing methods, such as test separators. MPFM allows for increase of the measurement frequency or even continuous monitoring, compared to traditional testing methods. The ABBON 3PM non-radioactive multiphase meter provides additional benefits compared to other multiphase meters, as it does not use any radioactive sensors, making it ideal for well surveillance, mobile- and fixed production well testing (see ref. 1). As part of KOCs strategy to introduce and evaluate new oil and gas production measurement technologies, the ABBON 3PM meter was tested to evaluate its suitability.
Go to Download Page
Email Reference
Document ID: A47E7D54

Installation effects on Venturi tubes in wet-gas flow conditions
Author(s): Emmelyn Graham Michael Reader-Harris Claire Forsyth
Abstract/Introduction:
Venturi tubes are one of the most common types of device used for wet-gas flow measurement as they are a simple, robust and cost-effective flow meter. They also form the main component in the majority of commercial wet-gas and multiphase flow meters. There are standards available for their use in wet-gas conditions ISO/TR 11583 and ISO/TR 12748. However, these mainly cover only 2-phase flows and horizontal installation. The performance of Venturis in 3-phase conditions, including the impact from using correlations derived for 2-phase flows, has more recently been investigated.
Go to Download Page
Email Reference
Document ID: 4DCA875F

Quantifying mixing efficiency in Automatic Pipeline Sampling
Author(s): Susithra Lakshmanan Jianbo Huang Wes Maru Andrew Thomas
Abstract/Introduction:
In custody transfer applications, crude oil is mostly transported as an oil-water mixture and the economic importance of quantifying the water-cut accurately has become increasingly significant. We have experimentally investigated the oil-water flow while also characterising the oil-water mixing efficiency of a prototype mixing device with a Jet In Cross Flow (JICF) configuration. As reported in a previous NSFMW (Lakshmanan et al 2015), such characterisation was achieved by commissioning a small multiphase flow loop (SMPFL) with 2.5 nominal pipe diameter at the University of Cambridge Magnetic Resonance Research Centre (MRRC) and by developing a Magnetic Resonance Imaging (MRI) pulse sequence and data acquisition methods. The data was also used to validate our CFD models, which are in turn utilised as a design tool to upscale the SMPFL to a large multiphase flow loop (LMPFL) with 10 nominal pipe diameter. For the industrial scale LMPFL, we developed a novel mixing product (SmartMix).
Go to Download Page
Email Reference
Document ID: 3C8DF5E7

A torsional vibrating mass flowmeter suited for large pipe diameters and high pressure
Author(s): Dag Wang1 Bjrn Erik Seeberg Christopher Grinde1
Abstract/Introduction:
A novel flowmeter is presented. The flowmeter is directly measuring the mass flow as well as the density of the flowing media. The flowmeter extends the operational area of conventional coriolis flowmeters into the large diameter and/or high pressure range. This is achieved through decoupling of the structure used for pressure containment and the structure used for vibrating the fluid. Furthermore, the outer tube of the flowmeter is not moving, therefore the flowmeter is well suited for submerged operation.
Go to Download Page
Email Reference
Document ID: E7F71009

Generalized Wet Gas Venturi Meter Correlations: Assessment and Improvement
Author(s): Martin Bjrnera Philip Fosblb Mads Lisberga Henrik Lisberga
Abstract/Introduction:
The venturi meter is perhaps the most suitable device for gas flow measurements in wet gas streams. As the presence of liquid in the venturi meter increases the differential pressure, a correction term is required to determine the actual gas flow. In this work we assess the associated error of six common wet gas correlations, against experimental venturi meter data from the literature. The results indicate that the Reader-Harris Graham correlation has the smallest deviations from experimental data. At low -ratios (?? ??/??) the de Leeuw correlation achieves similar deviations, but the errors become considerable at high -ratios. The de Leeuw correlation is improved for application with arbitrary -values. A correction term is suggested, to reduce the observed bias at low Lockhart-Martinelli values. Finally, it is shown that the function for n in the Reader-Harris Graham correlation can be approximated by a de Leeuw type correlation with a -dependency.
Go to Download Page
Email Reference
Document ID: 7E230DAF

Systematic bias in pro rata allocation schemes
Author(s): Armin Pobitzer
Abstract/Introduction:
Misallocation due to allocation uncertainty may result in increased exposure to economic risk for owners or stakeholders in hydrocarbon fields. It is often assumed that allocation errors are random and that they will even out over time, irrespective of the system setup and allocation uncertainty. In this paper, we show that this is normally not the case, even for simple allocation systems using standard pro rata allocation. For instance, a two-field pro rata allocation setup with a high measurement uncertainty for one of the meters compared to the other, causes the field with the highest allocation uncertainty to be systematically under-allocated. We show that this misallocation is inherent to the allocation system, and will occur even without any systematic measurement error present.
Go to Download Page
Email Reference
Document ID: B5AE9EA7

System Metering and Monitoring on Edvard Grieg
Author(s): Ausen Havard Berg Kjartan Larsen Marit
Abstract/Introduction:
Validation of multiphase measurements may be challenging. High accuracy measurements are only possible after the fluid has undergone phase transfer, mixing and shrinkage in the processing system. This paper will describe the model based system implemented on Edvard Grieg to monitor measurement inconsistency which shows a total overview of the field status allowing Lundin to produce closer to operating constraints. Comparison with real data will be shown.
Go to Download Page
Email Reference
Document ID: C8471A9E

Evaluation of a radiometric density meter in an export oil application
Author(s): Erik Sveinsvoll
Abstract/Introduction:
A clamp-on radiometric density meter type DT-9315 has been tested on export oil at the BP Ula platform from May 28 to October 5, 2015. The test has been executed in comparison with fast loop-bypass installed Solartron meter(s). Due to a maintenance shut the efficient duration of the test is 105 days. The results show that the radiometric meter provides fast and reliable density values with high correlation to the Solartron meters. With exception of short term process disturbances the daily average density difference throughout the test is 0.19 kg/m. Standard Deviation of the difference is 0.44 kg/m3. The difference increases with higher or lower flowrates outside a middle range, and temporarily after change of Solartron line. No instability or signal drift of the DT-9315 is observed during the test.
Go to Download Page
Email Reference
Document ID: 865DE49A

Operational experience with virtual flow measurement technology
Author(s): Jean Paul Couput Najla Laiani Vanessa Richon
Abstract/Introduction:
Since many years, operators have been using various multiphase and wet gas metering techniques. One of the reasons for implementing multiphase metering solutions was to replace test separator for topside and onshore applications as well as to develop subsea tie-ins by installing individual multiphase metering systems on each well. This has allowed to reduce development costs and to improve production optimization through continuous monitoring. In parallel so called virtual meters combining simple pressure & temperature measurements with flow model equations have been also evaluated and used with variable degree of success. The interest for virtual flow measurement has been re enforced recently with need to optimize metering schemes as well as to find out alternatives or complement to conventional multiphase meters (MPFM ) and wet gas flow meters ( WGFM ) for flow determination .
Go to Download Page
Email Reference
Document ID: 93D677DC

Did we miss anything? An Executive Summary about the Overview about the use of Multiphase Flow Meter: Past, Present, and Future.
Author(s): B. G. Pinguet
Abstract/Introduction:
Over the last 20 years, the development, evaluation, and use of multiphase and wet gas flow meters have been one of the main evolution for well performance against standard equipment (separators). Many metering systems have been developed at the early stage (90s), some died, some have merged to provide most suitable products, and a rationalization have been going on over 10 years (2000-2010), but the last 5 years started to see some new multiphase manufacturer companies emerging on the market from different domains. If it is clearly understood today that none of the technology or multiphase and wet gas meters on the market are capable to handle wide range of fluid types and Gas Volume Fraction (GVF) or Water Cut (WLR) with reasonable accuracy. Most of them cannot cope with all environmental conditions (pressure, temperature, H2S, Salinity, Solid) and therefore caution must be applied when contemplating the use of any Multiphase Flow Meter (MPFM) and Wet Gas Meter (WGM) versus some given applications.
Go to Download Page
Email Reference
Document ID: C00B984A

A Differential Pressure Meter for Low Reynolds Number Applications
Author(s): Craig Marshall
Abstract/Introduction:
Heavy oils are characterised depending on their density rather than their viscosity 1. Although there are various definitions for what constitutes heavy oil it is commonly agreed that the majority contain impurities such as asphaltenes, waxes and carbon residue. The API gravity definition, a common definition used in the oil and gas industry worldwide, states that heavy oil has an upper limit of 22. Figure 1 shows the upper and lower limits of various categories of oil as stated in the API gravity definition.
Go to Download Page
Email Reference
Document ID: 5611DC0B

A Method for Identifying and Reducing Errors in Wet Gas Measurement with Coriolis Meters
Author(s): Justin Hollingsworth
Abstract/Introduction:
Effective reservoir management over the life of a field demands regular measurement of individual producers and injectors. However, the capital cost to enable continuous, high-accuracy measurement is difficult to justify for many assets, and often, measurement is facilitated through permanent or mobile test separation units that provide a snapshot of production character once a month or even less frequently. Whether in its initial production or late in life, a single wells production could change suddenly or dramatically, leaving production engineers scrambling through scarce data to find the culprit well and identify an action plan to return asset production to target rate and/or specification. These searches for the source of a water breakthrough or a failed downhole completion can be tedious and cost up to months of production as data is examined and well tests trickle in. To an increasing degree, operators are driven to consider direct wellhead measurement options to ensure optimal recovery and quick response to individual well production issues.
Go to Download Page
Email Reference
Document ID: 1011DBD7

Application of the Magnetic Resonance Multiphase Flowmeter to Challenging Process Conditions
Author(s): Jankees Hogendoor Andre Boer Mark van der Zande
Abstract/Introduction:
Multiphase applications in the upstream oil and gas industry are renowned for the wide range of process conditions that can be encountered. To be able to measure multiphase flowrates under these challenging process conditions, KROHNE has developed a multiphase flowmeter based on magnetic resonance. In the current poster, some examples of applications are given, and the results obtained with the magnetic resonance multiphase flowmeter are discussed.
Go to Download Page
Email Reference
Document ID: BB03062A

Coriolis and ultrasonic flow meters in phase-contaminated oil flows
Author(s): Dennis van Putten Rene Bahlmann
Abstract/Introduction:
Oil and gas operators today are facing several significant measurement challenges in their efforts to optimize production and generate more from their reservoirs. One main challenge is how to deal with the measurement of multiphase flows. The application of multiphase flow meters (MPFMs) has increased significantly over the last decades to overcome this challenge. These MPFMs have in principle the capability of covering the entire multiphase flow regime, but may not be the best choice when considering costs and accuracy in specific regions of the multiphase flow domain.
Go to Download Page
Email Reference
Document ID: 55E229F6

USMs and Heavy Oil applications -The Woes of Transition and laminar Flow Measurement
Author(s): T. Cousins
Abstract/Introduction:
Heavy oil has three issues that can create measurement problems for liquid USMs. A. High viscosity causes low Reynolds number flows in the transition and laminar flow regimes. B. Temperature gradients, and therefore viscosity gradients, are common in laminar flows. C. High viscosity causes enhanced attenuation of ultrasonic waves. The paper explains these three issues in a practical simple way. By understanding these fundamental phenomena it becomes clear what the underlying implications to measurement are. For example, an USM may be linearized in the laminar / turbulent transition region produced by a volume flow rate at given flow conditions during a laboratory or field prover calibration. However, this transition zone is not fixed by a set volume flow range. The transition region is affected by various influences, such as installation affects, bulk fluctuations in fluid properties (e.g. temperature or composition changes), and local radial temperature / velocity gradients. Hence, a meter calibrated and linearized across one flow conditions volume flow transition region can have significant flow rate prediction biases if the meter is subsequently operated in other flow conditions (which shift the transition region). It is a challenge to predict the point at which a field installed meter will be influenced by transition. Transitional flow adversely affects the path taken by an ultrasound wave, and hence the USM performance.
Go to Download Page
Email Reference
Document ID: 06A2BE2F

Virtual Flow Meter - Sensitivity Analysis
Author(s): Stian Tangen Roar Nilsen Kristian Holmas
Abstract/Introduction:
Virtual flow metering becomes increasingly reliable and accurate enough to be accepted as an option to the physical flow meter. In order to prove the concept and to get an objective measure about the accuracy and the sensitivity, Kongsberg Digital has developed a new method for validating the design and securing a better understanding of the varying relationships for the system. This method indicates which parameters are the most important for a virtual flow meter to give an optimal accuracy. By using the latest technology within multiphase flow simulation and dynamic process simulators, a digital twin (virtual plant) can be utilized to replicate the behavior for the entire production unit. A virtual flow meter is then connected to this solution, with the same data exchange used for the real plant. Utilizing this method, a controlled environment (i.e. the virtual plant) is obtained while keeping the real plant behavior in abnormal or failure modes. The sensitivity analysis then introduces known and traceable errors / malfunctions in the virtual plant and monitors the Virtual Flow Meters ability to handle abnormal measurements and signal failures.
Go to Download Page
Email Reference
Document ID: 25B6928F

DP Meter Verification System - Operator Field Results and Practical Use
Author(s): Jennifer Rabone Kim Lewis
Abstract/Introduction:
Verifying the performance of any on line flow meter has its challenges. Standards are published in order to minimise the risk of unacceptable and unaccounted for measurement errors by offering clear and consistent requirements, specifications and guidelines in order to safeguard good meter performance. Operator specific guidelines are often used in addition to the standards. Site specific maintenance / inspection procedures are enforced in order to minimise the risk of financial exposure resulting from unforeseen or unpredictable problems which may cause an error or bias in meter system output. The majority of standards, guidelines and procedures were written on the assumption that it is not possible to verify the meter system performance in situ without external cross checks (e.g., pay and check meters or mass balance checks) and scheduled spot checks (e.g., calibrations and inspections). Cousins et al 1 highlighted the inefficiencies of such traditional verification methods which are not only financially costly but are often performed unecessarily, are performed too late to save a significant mis-measurement or are inconclusive and unhelpful.
Go to Download Page
Email Reference
Document ID: A7757390


Copyright © 2018