issue 57

spring 2008

Water calibrations for cryogenic applications Can flowmeters for application in cryogenic conditions be successfully calibrated using water at ambient conditions?

CONTACT: Asaad Kenbar - [email protected] www.flowprogramme.co.uk/projects

TUV NEL is currently collaborating with industry to address this question through a research programme which is designed to establish a framework of measurement standards for cryogenic liquids such as LNG.This research programme is fully supported by DIUS. A major milestone in the project was achieved recently with the completion of a test programme using a 2-inch Coriolis mass flowmeter. The flowmeter was initially calibrated at ambient conditions with water and then at cryogenic conditions with liquid nitrogen.

CONTD on page 2 … JOINT INDUSTRY PROJECTS

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A FLARE FOR MEASURING EMISSIONS

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UTILITY METERING

New research programme proposal

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CONTACT: Jane Sattary - [email protected] www.flowprogramme.co.uk/formulation

The DIUS National Measurement System’s Engineering and Flow Programme now has a rolling programme of research work so it is never too late to submit any flow-related issues that you feel the programme may be able to address. The formulation process has to date produced a full Engineering and Flow Programme proposal document for 2008 which is available for comment until Wednesday 30th April. This proposal document incorporates some of the key issues identified to date, however you are encouraged to continue to submit flow-related issues via the website for inclusion in further projects as part of the rolling formulation process.

CONTD on page 2 …

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Water calibrations for cryogenic applications

CONTD from front page

Flowmeter on test, courtesy of Krohne UK Ltd

The results using water as the calibration fluid at ambient temperature showed that the flowmeter performed well within its specified accuracy. The results from the liquid nitrogen measurements at -193°C initially showed that the flowmeter gave a consistent error of about 2 per cent throughout the test range, indicating a calibration shift. However, the performance of a Coriolis meter depends on the Young’s Modulus of elasticity of the vibrating tube, and this has a non-linear dependence on temperature. When the Young’s Modulus was corrected to the operating temperature of -193°C, the flowmeter produced measurements very close to its claimed accuracy of around 0.2 per cent (see graph).

A key conclusion is that the only correction that needs to be made in transferring water calibrations of Coriolis flowmeters to cryogenic flow measurements is to allow for the non-linear temperature dependence of the Young’s Modulus of elasticity of stainless steel.The results shown for the 2-inch test meter may well apply to a larger scale flowmeter which has the same material of construction, same tube shape and calibrated in the same way. However further tests are required to validate this conclusion.

The results from this research were presented at TUV NEL’s inaugural Production and Upstream Flow Measurement Workshop held in Houston recently. The full paper is available in workshop proceedings by contacting the events team: [email protected].

New research programme proposal

CONTD from front page

Over the past two years a number of priority flow-related topics have been identified through an extensive consultation with industry. Activities include formulation at: • dedicated formulation focus group meetings (e.g. North Sea Flow Measurement Workshop) • flow network and club meetings (e.g.Water Industry Flow Club) • conferences and exhibitions (e.g. Pharmatex)

• sector and international events (e.g. European Energy and Environmental Measurement Roadmapping event).

The formulation page on the website has been used throughout to keep stakeholders informed of progress and to identify industry needs.

Issues identified include improving the security of the UK’s energy supply by improving flowmetering for cryogenic fuels and high viscosity oil, and supporting environmental and regulatory compliance by addressing the flow measurement issues surrounding emissions and fluid properties. If you wish to provide feedback on the document for public comment please email: enquiry.nms@ dius.gsi.gov.uk.

www.flowprogramme.co.uk

TUV NEL – flow t i d ing s

Industry and research organisations continue to benefit from the world class facilities at TUV NEL through Joint Industry Projects (JIPs) designed to meet current and future measurement challenges.

TUV NEL is currently running a number of JIPs utilising the technical expertise of their staff and the unique test facilities. One of these, Multiflow III, is directed towards multiphase flowmeters used in the oil and gas industry.

Multiphase meters can improve well testing and field management operations by providing valuable real time production data, eliminating the time lag involved when using test separators. This can lead to significant cost savings in a number of areas, such as judging the timing of well shut-ins and optimising gas lift operations.

● The Engineering and Physical Science Research Council (EPSRC) has posted its three-year Delivery Plan. The specific research themes to be supported are Energy, The Digital Economy, Nanoscience and Next Generation Healthcare.

● The White Paper, Innovation Nation, published on 13 March 2008, sets out the Government’s aim to make the UK the best place in the world to run an innovative business or public service. ● OTC (Offshore Technology Conference) takes place from 5 – 8 May in Houston, Texas. Visit TUV NEL at stand number 2363-5.

● Technology Programme Calls: Applications for Phase 3 of the Autumn 2007 Competition for Funding close on 8 May 2008. The technology priorities in this phase are “Gathering Data in Complex Environments” and “Creative Industries”.

Clearly, multiphase flow measurement presents many operational and financial benefits over conventional measurement systems however there is still considerable uncertainty surrounding the suitability and performance of multiphase flowmeters in many applications.

The key overall objective of the Multiflow III JIP is to provide independent data and information on the performance and application of these flowmeters. The results from the project will assist engineers to make informed decisions when considering the potential benefits of multiphase flowmeters.

Robert Webb who is measurement and allocation advisor at BP America Inc. has recently commented that the tests currently being planned and undertaken by TUV NEL on the Mulitflow III JIP are “a primary foundation for subsea metering. This work will progress the industry a long way in understanding multiphase metering capability.” This JIP is now well underway with the testing of multiphase flowmeters such as the Flowatch from Pietro Fiorentini and the MPM meter from Multi Phase Meters AS.

New JIPs planned to commence this year focus on technically challenging areas such as non-invasive flow measurement, heavy oil flow measurement and validation of crude oil expansion coefficients. It’s not too late to participate in any of these JIPs - please contact Mark Roscoe for further information.

www.flowprogramme.co.uk

● The output from the recent event “Measurement Metrology Opportunities in the Hydrogen Economy” was captured in a series of mindmaps which are now available on the website. Some of the opportunities may form the basis of future collaborative projects in the Engineering and Flow Metrology Programme.

● The eighth All-Energy will be held at AECC, Aberdeen on 21 and 22 May 2008. It combines a major renewable energy exhibition and a conference covering all renewable sources and the challenges and opportunities facing the industry. TUV NEL will be exhibiting on Stand E29.

Further details on the above items and web links can be found at www.flowprogramme. co.uk/news

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CONTACT: Mark Roscoe - [email protected]

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Joint industry projects in 2008 NEWS

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A flare for measuring emissions

TUV NEL has been working closely with industry to examine the methods used to determine emissions from industrial flares and stacks, with the underpinning focus being on the difficulties and challenges associated with uncertainty assessment.

CONTACT: Jeff Gibson - [email protected] www.flowprogramme.co.uk/projects

The EU EmissionsTrading Scheme (EU ETS), and other key environmental legislation, place an obligation on energy intensive industries, such as the oil and gas industry, to accurately report greenhouse gas emissions. Although the monitoring and reporting guidelines are prescriptive in many aspects, there is a lack of detailed guidance on measurement methodology and the calculation of uncertainty.

The measurement of emissions from gas flares is one area which is proving to be somewhat troublesome. For reporting purposes, both the quantity of gas flared and the emission factor are needed to determine the amount of CO2 released. However, due to the hostile and unpredictable operating conditions experienced in flares, especially those located offshore, these parameters can be extremely difficult to monitor and sample.

TUV NEL has undertaken a number of flare measurement case studies within the oil and gas sector to evaluate the difficulties inherent in calculating and meeting the measurement uncertainty targets laid down in the associated legislation. Installations surveyed included the offshore Cormorant Alpha and Piper Bravo platforms, operated by Shell and Talisman Energy (UK) Limited respectively, and the onshore Kinneil Crude Stabilisation & Gas Processing terminal near Grangemouth operated by BP.

Through ongoing consultation with industry and focused research, TUV NEL plans to continue to tackle the complex issues involved with the measurement of emissions in order to assist industry in meeting its environmental commitments.

New flare gas standard

CONTACT: Jeff Gibson - [email protected]

TUV NEL’s expert on gas flow, Jeff Gibson, has recently drafted Energy Institute Guideline HM58 - The Determination of Flare Quantities from Upstream Oil and Gas Facilities.The document has been prepared in close collaboration with the upstream Hydrocarbon Management Committee Working Group (HMC 7) which includes representatives from the major oil and gas operating companies, technical consultants and equipment suppliers. Although aimed primarily at UK oil and gas operators, it is also expected to be a valuable aid to operators in other countries where similar controls on flaring are being enforced. The draft has been sent to the members of the HMC and HMC 7 Working Group for ballot, the deadline of which is 28th April 2008. Comments have also been invited from the American Petroleum Institute (API) Committee on Gas Fluids Measurement (COGFM) with a view to expanding the applicability of the document for global use in the future.

www.flowprogramme.co.uk

TU V N EL – flow t iding s

The application and importance of flow measurement cannot be underestimated when tackling environmental pollution. Its uses span from monitoring oil and produced water discharges to sea, to measuring greenhouse gas emissions to atmosphere.

The need to report this information accurately is reflected in supporting environmental legislation, where uncertainty of measurement continues as the main focal point.

However, feedback received by TUV NEL from industry and recent independent studies, shows that these measurement uncertainty limits are extremely difficult to achieve. Due to the nature of environmental reporting, the measurement conditions experienced are often unique and outside the scope of proven technologies.

A laboratory research project within the National Measurement System’s Engineering and Flow Programme aims to address some of these issues associated with emissions from flaring. The key objective is to test the latest measurement and modelling technologies against realistic field conditions. The results will provide both industry and equipment manufacturers with a broader insight and understanding into how installation effects can impact on flow measurement.

The work will also make available critical reference data to assist in the calculation of measurement uncertainty and give a level of confidence in the use of computational modelling techniques for the purpose of quantifying emissions.

Emissions – dates for your diary!

CONTACT: Lynn Hunter - [email protected] www.flowprogramme.co.uk/networks

Oil & Gas Emissions Seminar 11 June 2008, Aberdeen In what is proving to be a crucial and challenging year for environmental regulation, TUV NEL is pleased to announce its 2008 Oil and Gas Emissions Seminar.This one- day seminar will take a close look at the difficulties associated with reporting atmospheric emissions under the various environmental legislations.The seminar will investigate how industry can meet its obligations costeffectively using current technologies and how future technologies may be developed to achieve emissions reductions and improve monitoring techniques.

Measurement Uncertainty Training in Environmental Emissions 12 June 2008, Aberdeen With measurement uncertainty underpinning the whole credibility of environmental reporting, this one-day training course is designed to fully equip industry with

www.flowprogramme.co.uk

the fundamentals necessary for calculating measurement uncertainty. The course will include an interactive afternoon session focusing specifically on the application of measurement uncertainty for environmental emissions reporting.

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CONTACT: Lynn Hunter - [email protected] www.flowprogramme.co.uk/projects

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Flow measurement protects the environment

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Utility metering challenges for production lines

CONTACT: Emmelyn Graham - [email protected] www.flowprogramme.co.uk/projects

There are increased pressures on production industries by regulators to demonstrate energy efficiency and improvements within their systems. This greatly affects the food and drink manufacturing industry as it is the single largest manufacturing sector in the UK.

The DIUS Engineering & Flow Programme has responded to some of the issues with the launch of a collaborative project focusing on production line measurements to monitor and improve the efficiency and energy consumption within the food and drink sector.

Collaborators in this project are from companies interested in process improvements. These include large food producers, meter manufacturers and instrumentation companies. A recent collaborators’ meeting initiated the generation of industry case studies. These will highlight the potential benefits to companies of implementing effective monitoring of production lines to reduce utility consumption, in addition to general cost-saving strategies.The case studies will draw on the experiences of the members to address current barriers and provide much needed justification for the increased use of metering technology to monitor production lines. Although the project is already making good progress, new members are still welcome to join. Information can be obtained from the website or by contacting Emmelyn Graham.

Hydrocarbon flow measurement in South East Asia

CONTACT: Susan Tough - [email protected] www.tuvnel.com/events.aspx

Over 140 of the world’s leading oil & gas measurement specialists met at a top-level international conference recently.

The International South East Asia Hydrocarbon Flow Measurement Conference, hosted by TUV NEL, was supported by a technical committee that includes representatives from Petronas, BP, Chevron, Saudi Aramco, Roxar, Schlumberger, BHP Billiton and Shell.

The Workshop was opened by Zainal Din from Petronas, and the topic of his keynote speech was “Upstream Oil and Gas Measurement in Malaysia Today”. He highlighted the rapid progress over recent years in measurement technology in Malaysia’s upstream sector, and also focused on new measurement challenges in subsea and deepwater developments.

The papers presented during the Workshop sessions covered new applications and technologies, calibration methods and new calibration facilities. A recurring theme was the application of single and multiphase flow meaurement to challenging fluids such as viscous oils, emulsions, and fluids with high asphaltene content. Six papers reflected continuing development and refinement of ultrasonic flowmeter technology and calibration.

The prize for best paper was awarded to Nick Paris, BHP Billiton, for his paper on “Applications of Subsea Multiphase Flow Meters in the Development of Oil with Emulsion Forming Tendency”. This paper was a good example of combining tests in TUV NEL’s multiphase flow facility with exploitation of the results in specifying and selecting subsea flowmeters for a number of production wells. Copies of the proceedings can be obtained by contacting the Events Team: [email protected].

www.flowprogramme.co.uk

TUV NEL – flow t i d ing s

A number of ISO Technical Reports relating to and supporting the standard on differential pressure flow measurement (ISO 5167) are currently being progressed.

A Code of Practice (ISO/TR 9464) for ISO 5167 is expected to be published later this year. It provides users with further guidance on the use of the standard. In particular, it gives a simplified formula (developed under the NMS Flow Programme) for the Joule-Thomson coefficient used in temperature correction across an orifice plate. This formula is easier to use because it avoids the need to know the gas composition. It is the same formula that the UK Oil & Gas Regulator already expects Operators of all UK Terminals to be using for Sales Gas Flow (see Policy Statements on www.og.dti.gov.uk/upstream/measurement ).

A relatively inexpensive method of measuring the flow of gas with small amounts of liquids is to use an orifice plate with a liquid by-pass. Recent data obtained under the current DIUS programme of flow research has provided good supporting data to give confidence in the use of this method. An amendment to the relevant ISO Technical Report on orifice plates with drain-holes (ISO/TR15377) will promote the use of this cost-effective method of measurement.

The ISO Standards Committee responsible for Flow Measurement (ISO/TC 30) have given their approval for the production of a new ISO Technical Report (TR) on wet gas flow measurement. It is expected that this TR will make recommendations on the correlations to be used for the over-reading in gas flow caused by the liquid phase. Further work on developing and confirming these correlations is planned. The TR will also provide guidance on installation and operating procedures for achieving improved measurement accuracy.

Anyone interested in contributing to the above mentioned activities or seeking further information on flow measurement standards activities should contact Dr Reader-Harris, Chairman of the British Standards Committee on differential pressure flow measurement (BSI CPI 30/2) and Convenor of the Wet Gas Measurement Working Group of the equivalent ISO Technical Committee (ISO/TC 30/SC 2).

Transport Minister visits TUV NEL

The Rt. Hon. Rosie Winterton MP, Minister of State at the Department for Transport, recently visited TUV NEL and Ecebs, another East Kilbride based company, to find out about their work on future transport systems.

During her visit to TUV NEL she found out about the company’s involvement in developing technology to reduce the impact of transport on the environment and measurement research into fuels of the future.

www.flowprogramme.co.uk

From left to right: Bob Holmes, Head - Business Development, TUV NEL; Rt Hon Adam Ingram, MP; Rt Hon Rosie Winterton MP; David Braddock, Managing Director, Ecebs

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CONTACT: Dr Michael Reader-Harris, [email protected] www.flowprogramme.co.uk/networks/standards

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Flow measurement standards - update

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Events in the pipeline

www.flowprogramme.co.uk/events

Produced Water Workshop, 23-24 April 2008, Aberdeen

This event is for interested parties to find out and keep abreast of the latest technological and legislative developments, as well as current practices and trends in produced water management, treatment and handling.

Principles and Practice of Flow Measurement, 6-8 May 2008, East Kilbride

This three-day course is designed for the engineer who needs to gain a sound knowledge of flow measurement methods, to know how to choose the best flowmeter for a particular need and how to get the best from the meter when in service.

Oil & Gas Emissions Seminar, 11 June 2008, Aberdeen Key environmental legislation places an obligation on energy intensive sectors to report their greenhouse gas emissions effectively.The oil & gas industry faces challenges and difficulties in meeting obligations.This one-day seminar aims to bring industry together to share knowledge to help establish solutions. Measurement Uncertainty Training Course, 12 June 2008, Aberdeen

With measurement uncertainty underpinning the whole credibility of environmental reporting, this one-day training course is designed to equip industry personnel with the fundamentals necessary for calculating measurement uncertainty.

Oil-in-Water Monitoring Workshop, 18 September 2008, Aberdeen

This one-day Workshop will present the latest technological and legislative developments as well as current practices and trends in oil-in-water analysis, monitoring and measurement.

26th International North Sea Flow Measurement Workshop, 21-24 October 2008, St Andrews

This Workshop is the premier world event where specialist engineers, involved with all aspects of oil & gas production, meet to review flow measurement methods, techniques and advances.

Introduction to Flow Measurement, 11-12 November 2008, East Kilbride

This two-day training course is intended for anyone who is new to flow measurement or who wants to refresh their basic understanding of flow measurement.

Forthcoming meetings

Oil & Gas Focus Group, 23 April 2008, Aberdeen http://ogfg.flowprogramme.co.uk Produced Water Club, 25 April 2008, Aberdeen www.producedwaterclub.com Oil & Gas Focus Group, 4 June 2008, Norwich http://ogfg.flowprogramme.co.uk Water Industry Flow Club, 5 June 2008, Birmingham http://wifc.flowprogramme.co.uk

Recent publications

www.flowprogramme.co.uk/publications

Report No. 2007/186: Parametric Study for Ultra-low Liquid Flow in Micro-conduits Report No. 2007/239: Assessment of Calibration and Traceability Requirements for Ultralow Flowrates Report No. 2007/76: Application of MEMS Ultrasonic Transducers to Flow Measurement

East Kilbride, Glasgow G75 0QF, United Kingdom Tel: + 44 (0) 1355 220222 Fax: + 44 (0) 1355 272999 email: [email protected] web: www.tuvnel.com Flow Tidings is a quarterly publication of TUV NEL, sponsored by DIUS’s Engineering & Flow Programme. The articles in Flow Tidings are intended to inform the reader but do not represent the opinion or policy of DIUS and TUV NEL. For mailing list corrections or additions, please contact Susan Tough, Tel: +44 (0) 1355 272858 Fax: +44 (0) 1355 272999 e-mail:[email protected]

issue 58

summer 2008

Live crude oil density characterisation

CONTACT: Mark Roscoe - [email protected] www.flowprogramme.co.uk/projects

In view of the major economic impact of any errors in determination of crude oil volumes, there is an urgent requirement to check the validity of generic expansion coefficients applied to live crudes.

Measurements of crude oil volumes at elevated temperatures and pressures are converted to standard conditions for trading purposes using these generic crude oil expansion coefficients. However the data on which the coefficients are based may not be representative of current live crude oils containing substantial amounts of water or natural gas liquids.

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CONTD on page 2 … NON-INVASIVE FLOW METERING

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TOMOGRAPHY APPLICATIONS

National Wind Energy Metrology Centre established

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CONTACT: Alistair Mackinnon - [email protected] www.flowprogramme.co.uk/projects

The Government’s recent announcement that an additional 7,000 wind turbines are to be built across the UK by 2020 indicates the significance of wind energy in helping to meet the UK CO2 reduction targets. In addition, the Government is encouraging wider utilisation of microgeneration technologies and small wind turbines will be a key part of this. To support Government policy, TUV NEL has established a National Wind Metrology Centre (NWMC) with support from the Department for Innovation, Universities and Skills National Measurement System (NMS) Innovation R&D Programme and the renewable energy sector.

TUV NEL’s wind turbine test site

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Live crude oil density characterisation

CONTD from front page

Crude oil is traded in units of the volume it would occupy at standard conditions (15°C and 1.01325 bar) of temperature and pressure. Often, this standard volume must be calculated from a value of the oil density measured at high temperature and pressure. This calculation is usually done by applying generic expansion coefficients developed by the American Petroleum Institute (API) to the measured density. However the API expansion coefficients were derived from data that may not be fully representative of typical live crudes containing substantial amounts of water or natural gas liquids.

Clearly, since crude oil is traded in large volumes of increasingly high value, the economic impact of using inappropriate expansion coefficients could be very significant. There is therefore a requirement for accurate density data for live crude oils to allow operators to assess their financial exposure resulting from errors in the API coefficients. TUV NEL has recently launched a Joint Industry Project (JIP) to address this need. TUV NEL’s unique measurement facilities will be used to accurately measure the densities of live crude oils as functions of temperature and pressure. Staff expertise in thermophysical property modelling will be applied to analyse the data and assess the impact of differences between the data and the API expansion coefficients.

This work will follow on from the current successful Liquid Densitometer Calibration JIP operated by TUV NEL and sponsored by a number of key companies in the oil and gas industry. The objective is to develop a calibration procedure that links traceably to National Standards, thus increasing confidence in liquid densitometer measurements. Fourteen operators, a densitometer manufacturer and the UK oil and gas regulator (part of the Department for Business, Enterprise and Regulatory Reform) are participating in this work.

The key task in the current JIP is the detailed characterisation of densitometers in well-controlled conditions, making use of accurately-characterised transfer standard fluids that cover the density and viscosity ranges that are encountered across the full temperature and pressure range of operation of UK offshore oil facilities. This work is now approaching completion, but the pressing issue of the use of inappropriate methods to account for the effects of temperature and pressure on crude oil volume has been identified. If you are interested in becoming involved in the new JIP, please contact us.

National Wind Energy Metrology Centre established The NWMC will address a range of measurement issues in wind turbines (both onshore and offshore applications) and also in small wind turbines. The NWMC will utilise existing test facilities within the Energy Technology Centre at TUV NEL and its wind turbine test site at Myres Hill near East Kilbride.

CONTD from front page

The size of large wind turbines is increasing, possibly up to six or seven MW for offshore applications. This will place increasing emphasis on measurement systems for structural condition monitoring and for remote wind speed sensing.

Small wind turbines up to 100 kW operate at variable rotational speeds in response to transient wind conditions. The UK has international leadership in this sector, so the NWMC initiative is timely in addressing measurement issues relating to transient wind speed, power output and noise. Because small wind turbines may be mounted adjacent to residential properties, the measurement of noise for different wind turbine designs is a critical factor.

The NMS support, together with extensive collaboration and co-funding from industry, will help to secure the small wind sector as a key strength in the UK economy.

www.flowprogramme.co.uk

Accounting for energy use within entire process plants has become more established due to the increased pressure for energy efficiency and compliance with environmental regulations. However, understanding energy and raw material consumption at production line level still remains to be addressed.

TUV NEL in collaboration with industry has been focusing on utility consumption at the production line level, addressing some of the issues using flow metering. Case studies are providing vital evidence to justify the installation of metering technology on individual production lines. Information from the measurements can be a fundamental requirement for process optimisation, reducing utility consumption and for complying with ever increasing environmental regulations. The many barriers to the use of metering technology within individual production lines are also being actively explored.

● The North Sea Flow Measurement Workshop will be held in St Andrews, Scotland from 21 to 24 October 2008. The event focuses on the application and development of flow measurement methods. Online booking is now open. ● The World Bank, who manage the Global Gas Flaring Reduction (GGFR) Partnership, are seeking feedback on their new draft guidelines covering flare and vent measurement. Feedback can be provided via the TUV NEL Emissions Club.

● UK Trade & Investment (UKTI) and TUV NEL are working closely to promote flow measurement in the Latin America region. A heavy oil workshop in conjunction with Petrobras and local universities will take place early in December 2008 in Brazil. ● ONS, a world leading exhibition for the energy business, will take place from 26 to 29 August 2008 in Stavanger, Norway. The event provides direct access to an offshore sector where investment worldwide is set to reach record levels over the next few years. ONS attracts international attention with sectors including Liquified Natural Gas and Arctic Exploration and Production.

One case study with a multi-national food manufacturer is focused on the complexities of metering steam used for heating and sterilising foods. The study includes improvements made following calculations of energy flows and losses from actual measurements. Areas have been identified for further improvements and where additional cost-effective measurements could be advantageous in improving overall process efficiency.

Instrumentation or process companies requiring further information of the benefits or wish to join the collaboration should contact TUV NEL.

www.flowprogramme.co.uk

● TUV NEL has been awarded a contract by Expro to carry out calibration of Petrotech wet gas flowmeters (now part of Expro) within the wet gas flow measurement facility.

Further details on the above items, contacts and web links can be found at www.flowprog ramme .co.uk/ news

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CONTACT: Emmelyn Graham – [email protected] - www.flowprogramme.co.uk/projects

NEWS

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Managing utility consumption within process industries

TUV NEL – flow t i d ing s

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Non-invasive flow metering

The use of non-invasive flow metering techniques potentially offers significant benefits, but there is currently little comparative data available to confirm the claims of accuracy and suitability being made by meter manufacturers. A TUV NEL led Joint Industry Project aims to increase the confidence in the use of non-invasive flow measurement which offers significant benefits.

The primary benefit is that production is not interrupted. Other benefits include no contact with hostile fluids, no moving parts to wear or break, no fluid leakage or process contamination and no pressure drop or energy loss. In addition there are operational benefits such as the ability to cope with change of use of plant or pipeline and ease of removal for maintenance, recalibration or replacement.

The aim of the research is to assess and compare the performance and possible roles of different non-invasive flow metering technologies. In addition to ultrasonics, other technologies such as nucleonic, sonar, acoustic emission, pulse-echo and ECT tomography will be considered.

Thirty years and still flowing CONTACT: Susan Tough - [email protected] www.flowprogramme.co.uk/events

Understanding the importance of selection, installation, calibration and maintenance of flowmeters requires a basic knowledge of flow metering technology.

TUV NEL’s premier and established Principles and Practice of Flow Measurement Course was held in May at its facilities in East Kilbride. This intensive and comprehensive course attracted the highest-ever attendance in its 30-year history. A total of 13 countries were represented, from as far afield as Kenya, United Arab Emirates, South Africa and Canada.

TUV NEL staff, all of whom are experts in their technical fields, provided in-depth coverage of metering technologies through a series of lectures and hands-on training within the National Flow Measurement Standard Facilities. The demonstrations assisted delegates to put into practice what they had learned from the lectures and to help in their understanding of the theoretical principles of flow measurement. Delegates were able to see how different types of flowmeters should be selected, calibrated, installed and maintained. The highly positive feedback from delegates included the following comments: “an excellent course with excellent presenters”, and “the course was greatly relevant to my job”.

The Introduction to Flow Measurement Course which is aimed at engineers who are relatively new to flow measurement will be held from 11-12 November 2008. The 2009 Principles and Practice of Flow Measurement Course will take place from 12-14 May.

www.flowprogramme.co.uk

TU V N EL – flow t iding s

ConocoPhillips was one of the first partners to sign up to the JIP. Gordon Stobie, supervisor of Flow Measurement Engineering within ConocoPhillips’s Production Technology Group, comments: “We believe that this new technology will prove very valuable to major operators such as ourselves as more marginal fields come on stream and primary assets mature as we can ensure accurate flow measurement without the need for costly intervention.

“The TUV NEL JIP is a very important part of ensuring that the benefits of non-invasive flow metering are realised by the industry.”

A number of British and international standards for ultrasonic flowmeters are currently being progressed.

The revised standard (BS 7965) on ultrasonic flowmeters for industrial gas is out for public comment and BS 8452 on clamp-on meters for liquids is under revision with a possible extension of scope to cover meters for liquids and gases. The International Standard ISO 17089-1 on ultrasonic meters for custody transfer and allocation of gas is due for ISO TC30 committee vote in the near future. In addition API Manual of Petroleum Measurement Standards 5.8 (2005) on measurement of liquid hydrocarbons has been submitted as a new work item for possible adoption as ISO 18313.

Tomography applications in flow measurement The UK has a worldwide lead in process tomography, the application of which provides imaging techniques that enable chemical process manufacturers to estimate the spatial distribution of phases and chemicals inside vessels. These techniques could also lead to major advances in flowmeter calibrations.

CONTACT: Norman Glen – [email protected] – www.flowprogramme.co.uk

The UK has a strong academic track record in the development of tomography, with several universities active in this area, particularly in its application to chemical process monitoring. In chemical processes, knowledge of the spatial distribution of phases and chemical species is generally important rather than Image courtesy of ITS determination of flow rates inside reactor vessels. However, tomographic techniques can be used to improve flow measurement in complex systems such as wet gas, multiphase and high viscosity fluids, by providing information on flow patterns and phase distributions. Such information can be used to improve the performance of existing flowmeters and assist the development of new measurement techniques.

Image courtesy of ITS

www.flowprogramme.co.uk

Advanced flow metering techniques will have an important role in new developments aimed at ensuring the continued security of the UK’s energy supply, for example through the use of cryogenic fuels and high viscosity oils. TUV NEL will therefore be evaluating applications of innovative tomographic techniques to enhance the UK National Flow Measurement Facilities at East Kilbride.

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A particular issue to be studied is how these techniques can be used either to supplement each other or to supplement embedded meters. Evaluation is planned in single and multiphase flows. In relation to ultrasonics, the novel aspect of the project is associated with assessing to what extent the accuracy of single-path clamp-on meters can be improved by using them in distributed multi-path groups rather than at a single point.

flowt id ing s

CONTACT: Richard Whitson - [email protected] www.flowprogramme.co.uk/projects

Progress of documentary standards

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T U V N E L – f l ow t i d i n g s

Water Industry Flow Club ‘energy and flow’ meeting CONTACT: [email protected] – www.flowprogramme.co.uk/networks

Water Industry Flow Club members attended their latest meeting in Birmingham to discuss the energy challenges facing the water industry. Recent increases in energy prices, together with ongoing concerns on climate change and global warming, gave a sharp and timely focus to their June meeting on “Energy and Flow”.

Presentations at the meeting covered carbon accounting, small-scale hydro-electric power in water networks, energy savings in rotodynamic pumping systems, and water resourcing in new urban developments.

Carbon accounting is now a mandatory part of a water company’s business plan that is submitted to the regulator, Ofwat, as part of the five-year pricing review. One of the presentations gave an excellent practical illustration of how carbon accounting is done in a water industry application. A worked example of a simple pumping station with a connecting pipeline was used to show how to calculate the equivalent tonnes of carbon dioxide that would be produced over the lifetime of the asset.

The other interesting presentations highlighted diverse aspects of energy saving and usage, for example:

● using a turbine in a water network to generate power in the 30 – 150 kW range for sale into the grid.

● large energy savings in rotodynamic pumping systems through use of variable speed drives and improved system

design

● potential reduction in carbon emissions through improved management of the demand for water

Understanding such calculations can have a significant influence on the commercial viability of plant operators.

For further information on the Club and a closer look at the individual presentations go to the Club website.

Water industry events – dates for your diary Water Industry Flow Club Meeting 18th September 2008 Marston’s Beer Company, Burton upon Trent The theme for the next meeting is “Water abstraction flow”. This will include a morning of presentations followed by a tour of Marston’s brewery. Items on the agenda include a presentation by Marston’s on brewery abstraction and measurement of the water flow, and a presentation on groundwater modelling for informing water abstraction issues.

WWEM 2008 5th & 6th November 2008 Telford International Centre, Telford. TUV NEL will be presenting at the Water, Wastewater and Environmental Monitoring 2008 event promoting the activities of Water Industy Flow Club and future research in the Engineering and Flow Programme. The output from the recent project to obtain total daily uncertainty in measurement of open channel flow will be highlighted.

www.flowprogramme.co.uk

TUV NEL – flow t i d ing s

TUV NEL’s inaugural Emissions Seminar, held in Aberdeen recently, was a highly successful event and attracted a wide range of delegates from across the oil and gas sector and representatives from the World Bank Group’s Global Gas Flaring Reduction Partnership (GGFR). The event provided a focused opportunity at this crucial time for industry to share its experiences in controlling and reporting atmospheric emissions to meet the growing environmental legislative requirements. With the main theme of the event being the EU Emissions Trading Scheme (ETS), leading oil and gas companies and industry experts discussed changes and approaches necessary to meet the extensive monitoring and reporting requirements. As well as outlining the main challenges and difficulties facing the industry, the seminar allowed an insight into the latest techniques being used to improve the measurement of emissions from flares, which remains the most challenging area in the EU ETS.These included calibration using radioactive tracers and a novel verification technique for ultrasonic flare gas meters.

Other topics included offshore fuel emissions monitoring of combustion plant TUV NEL representatives with speakers and chairpersons from BP Exploration and Production to comply with the requirements of the Ltd, GE Sensing, ISR Consultants Ltd, Performance Improvements Group (PI) Ltd, RSK Group, StatoilHydro and Tracerco. recently expanded Offshore Combustion Installations (Prevention and Control of Pollution) Regulations. Establishing Best Available Techniques (BAT) to meet these Regulations continues as a main priority for the offshore sector.

The seminar prompted much discussion and debate throughout the day and highlighted the need for across-theboard collaboration to meet the top level requirements of current legislation and to prepare industry for the changes anticipated to meet future environmental legislation. The oil and gas industry will continue to tackle much of these issues and challenges through the work of the TUV NEL Emissions Club, to establish cost-effective solutions and industry best practices.

Website publications database

CONTACT: Christina Emans - www.flowprogramme.co.uk/publications

The Programme website offers a catalogue of flow metering research papers spanning more than 20 years, fully searchable by keyword, author or phrase. Papers presented at TUV NEL events and other flow workshops and conferences are also listed in the database as a key source for industry. This catalogue of papers is regularly updated. Flow Research reports, Guidance Notes and Best Practice Guides are also available from the publications page of the website and are fully downloadable.

www.flowprogramme.co.uk

p a ge 7

CONTACT: Lynn Hunter – [email protected] www.emissionsclub.com

flowt id ing s

Emissions seminar brings industry together

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flowt id ing s

T U V N E L – f l ow t i d i n g s

Events in the pipeline

www.flowprogramme.co.uk/events

Oil-in-Water Monitoring Workshop, 18 September 2008, Aberdeen This one-day Workshop will present the latest technological and legislative developments as well as current practices and trends in oil-in-water analysis, monitoring and measurement. Measurement Uncertainty Training Course, 20 October 2008, St Andrews

Measurement is fundamental to the control of quality, efficiency and safety. Designed to impart an understanding of measurement uncertainty using examples tailored to the oil and gas sector, delegates will receive practical guidance on the design of measurement techniques for improved uncertainty.

Thermodynamics of Fluid Systems Training Course, 20 October 2008, St Andrews

This one-day course is intended for those who are new to the thermodynamic behaviour of fluids or who wish to refresh their basic understanding of the subject.

26th International North Sea Flow Measurement Workshop, 21-24 October 2008, St Andrews

This Workshop is the premier world event where specialist engineers, involved with all aspects of oil & gas production, meet to review flow measurement methods, techniques and advances.

Introduction to Flow Measurement, 11-12 November 2008, East Kilbride

This two-day training course is intended for anyone who is new to flow measurement or who wants to refresh their basic understanding of flow measurement.

Produced Water - Best Management Practices, 26-27 November 2008, Kuala Lumpur, Malaysia

This event is designed for those who are concerned with oil & gas production processing, in particular produced water management, treatment and handling.

The Americas Workshop, 3-5 February 2009, Houston, USA

Following the success of the inaugural Workshop earlier this year, this three-day event will address the changes in flow measurement practice and technology which affect North, South and Central America.

Principles and Practice of Flow Measurement Course, 12–14 May 2009, East Kilbride

This three-day course is designed for the engineer who needs to gain a sound knowledge of flow measurement methods, to know how to choose the best flowmeter for a particular need and how to get the best from the meter when in service.

Forthcoming meetings

Oil & Gas Focus Group, 10 September 2008, Aberdeen http://ogfg.flowprogramme.co.uk Water Industry Flow Club, 18 September 2008, Burton upon Trent http://wifc.flowprogramme.co.uk Oil-in-Water Club, 19 September 2008, Aberdeen http://www.oiwclub.com Emissions Club, 9 October 2008, Aberdeen http://www.emissionsclub.com

Recent publications

www.flowprogramme.co.uk/publications

Report No. 2007/186: Assessment of Calibration and Traceability Requirements for Ultralow Flowrates Report No. 2007/76: Application of MEMS Ultrasonic Transducers to Flow Measurement Report No. 2007/186: Parametric Study for Ultra-Low Liquid Flow in Micro-Conduits East Kilbride, Glasgow G75 0QF, United Kingdom Tel: + 44 (0) 1355 220222 Fax: + 44 (0) 1355 272999 email: [email protected] web: www.tuvnel.com Flow Tidings is a quarterly publication of TUV NEL, sponsored by DIUS’s Engineering & Flow Programme. The articles in Flow Tidings are intended to inform the reader but do not represent the opinion or policy of DIUS and TUV NEL. For mailing list corrections or additions, please contact Susan Tough, Tel: +44 (0) 1355 272858 Fax: +44 (0) 1355 272999 e-mail:[email protected]

NATIONAL MEASUREMENT SYSTEM FLOW NEWSLETTER

ISSUE 59 AUTUMN 2008

Programme of change for a brighter future Our economy has never been more influenced by global issues than it is now. In the next few years, energy supply and environmental management are likely to be two of the most talked about subjects in the UK and in most other developed countries. Continued on Page 2

INSIDE>>

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HEAVY OIL LAUNCH OF NEW JIP

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UK GAS DISTRIBUTION

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AMERICAS WORKSHOP ANNOUNCED

www.flowprogramme.co.uk Continued from Page 1

Programme of change for a brighter future

www.flowprogramme.co.uk/news

With high oil prices, international carbon commitments and an increasing reliance on imported energy, accurate flow measurement will be more important than ever before. A new programme of flow research commenced on October 1, 2008, which will build on the world leading research made in recent years in areas such as the flow metrology of emerging energy sources, including heavy oils and liquefied natural gas (LNG), whilst also introducing important new areas of flow research. Flow measurement technologies that support the ability to measure emissions to the environment have a key role in ensuring that the UK meets its environmental emissions targets. Projects in the new Programme will address a range of topics including fuel and flare gas emissions and issues associated with carbon capture and storage. The new Programme will also progress the flow measurement of complex flows, which have traditionally been difficult to quantify, and will address the measurement challenges of open channel flow. Overall, there is a clear focus in the new Programme to assist UK industry in addressing new challenges in flow measurement over a broad spectrum.

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The new Programme will help in the continued development of the National Flow Measurement Standards facilities which aid the advancement of flow measurement technologies, techniques and practice. It will also ensure industry has access to the best flow metering R&D, calibration and testing facilities, together with a knowledge base at the forefront of worldwide capabilities.

As worldwide reserves of light crude oil diminish rapidly and alternative sources of renewable energy remain in their infancy, attention is being turned to the world’s vast deposits of heavy oils and tars. Recovery and processing of these viscous hydrocarbons creates fresh challenges for accurate measurement of the produced fluids. A new JIP at TUV NEL will assess the readiness of our flow metering technologies for this demanding and developing market. The accuracy of traditional flowmeters in high viscosity fluids has yet to be fully tested, although it is reasonable to suspect that different technologies will be affected in different ways. Heavy oils do not flow easily, leading to higher pressure losses across bends and restrictions. In addition, they more readily entrain secondary components such as gas or sand, and can build up in layers on contact surfaces. Their velocity profiles (which describe the variations in fluid speed that develop over the pipe cross-section) can also differ markedly from those of low-viscosity products like kerosene. Such effects have a direct impact on the performance of the metering technologies employed. These issues were addressed by TUV NEL in a recentlycompleted National Measurement System (NMS)

ISSUE 59 AUTUMN 2008

Heavy oil research continues with the launch of a new JIP

NEWS

Further details on any of our News items and links can be found at www.flowprogramme.co.uk/news

■ UKTI & TUV NEL are working closely to promote flow measurement expertise in the Latin America region. A Heavy Oil Workshop in conjunction with Petrobras and PUC-Rio will take place on 4 - 5 December 2008 in Brazil. ■ The Water Industry Focus Group will present ‘Facing Challenges in the Water Industry’ at WWEM, Telford 5-6 November. ■ The Energy Institute Awards Dinner Ceremony takes place on 19 November in London. The Awards categories include Environment, Innovation, Technology and Communication. ■ BWEA will be hosting one of the largest renewable energy conferences ever held in the UK at the ExCeL Centre in London’s docklands from 21-23 October. TUV NEL will be exhibiting on stand number 315.

www.flowprogramme.co.uk/projects

research project, where the performance of a selection of Coriolis and ultrasonic flowmeters was investigated at fluid viscosities up to 300 cSt and in the presence of up to 10 per cent by volume of entrained gas. The results suggest that the transfer of these traditional technologies from low-viscosity to high-viscosity service may be far from straightforward. A frequent claim made for Coriolis meters is their low sensitivity to the fluid viscosity. However, in the tests conducted at TUV NEL a number of observations were made – such as apparent “zero offset” variations – that merit further exploration before such meters can be confidently applied, without adjustment, in high or varying viscosity conditions. Pressure loss, due to the reduced bore and convoluted shapes of their internal flow tubes, was also shown to be a limiting factor on the flowrates achievable with the Coriolis meters at higher fluid viscosities.

■ Valve World 2008 Conference and Expo will take place in Maastricht, The Netherlands, from 4-6 November 2008. The event is an international platform where piping, valve and flow control professionals can update their knowledge of valve applications in a variety of industries.

Pressure loss was less of an issue for the non-intrusive ultrasonic devices. However, since they operate by sampling the fluid velocity at only discrete points within the pipe cross section, their basic response was shown to be highly sensitive to the precise shape of the velocity profile. Accurate modelling or actual measurement of this important parameter will clearly be vital to maintain metering accuracy under elevated (and potentially changing) viscosity conditions. The uncompensated flowrates reported by both types of meter showed significant deviations in the presence of gas, even at quantities as low as one per cent by volume. Awareness of such issues is growing steadily among manufacturers and end-users alike, with significant research now being focused on their correction or mitigation. To continue the process of evaluation, a new Joint Industry Project has been set up by TUV NEL to explore the capabilities of the new generation of metering technologies. Other conventional devices, which show potential for the heavy oil market, will also be considered. This JIP will extend the previous programme of work to even higher viscosities (600 cSt) and to even more demanding viscous flow conditions.

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© BP p.l.c.

www.flowprogramme.co.uk

www.flowprogramme.co.uk/projects

UK gas distribution-going the extra mile National Grid is an international electricity and gas company and one of the largest investor-owned energy companies in the world. The company owns and operates the National Transmission System (NTS) for gas distribution throughout Great Britain. Its distribution networks comprise almost 50 per cent of Britain’s gas distribution system which receive an average of 200 million cubic meters per day of gas into the NTS. Gas is distributed over a network of approximately 82,000 miles, and local distribution networks deliver gas to some 11 million meters in homes and businesses in Britain.

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National Grid plc has entered into a partnership with TUV NEL to further increase accuracy and confidence in flow measurements in the UK’s gas distribution system. They have also provided substantial co-funding to the DIUS National Measurement System (NMS) programme of work on orifice flowmetering.

The challenges of delivering a reliable gas supply in the face changing patterns of supply and demand require the highest level of accuracy and confidence in the flowmeters installed throughout the gas distribution system. The most common flowmeter type used by National Grid is the orifice meter, which accounts for some 90 per cent of all distribution flowmeters. The orifice plate is a simple and cost-effective flowmeter when installed under ideal flow conditions. However, contaminants in gas streams, such as grease, particulate solids or sludge, can degrade the meter’s performance. Under the current NMS programme of work, TUV NEL has already developed a predictive model to determine the effects of contamination on the performance of orifice meters. The additional programme of experimental work agreed with National Grid will allow further development and verification of this model for orifice flowmetering.

ISSUE 59 AUTUMN 2008

Flowmetering paves the way for spot trading of LNG Traditionally liquefied natural gas (LNG) has been traded on the basis of long-term contracts using tank volume measurements. However flow metering will be much more appropriate if LNG is increasingly traded on the basis of spot prices in the same way as crude oil. The complexities and expense of producing and shipping LNG has meant that it has traditionally been traded on the basis of long term contracts, with measurements made by tank volume. However, as production of LNG grows, it is likely to be traded internationally on the basis of short-term (spot) prices in a similar way to crude oil. In such circumstances the established method of measuring LNG by tank volume becomes impractical. As a result flow metering, the accepted method of measuring crude oil, will need to be adopted at receiving terminals for custody transfer of LNG. TUV NEL is currently undertaking research to help establish a framework of LNG measurement standards

and flowmeter capabilities supported by the UK government’s National Measurement System under the Department for Innovation, Universities and Skills. The project started with a review of the existing methods of LNG measurement systems, calibrations and uncertainties and progressed to testing proven flowmeter technologies under cryogenic conditions. It has concluded that one of the most established and widely used methods of flow metering in other applications – Coriolis mass flow measurement – has the potential to be an accurate and a suitable method of measuring LNG flows. The research programme is now currently focusing on multi-path ultrasonic flow metering technology. Tests with one particular instrument are planned at cryogenic conditions and the results will be reported in the near future. Results from the Coriolis and ultrasonic flowmeter tests will be utilised in the development of general calibration concepts for these flow metering technologies.

A new generation of engineers

To meet the growing demand for flow measurement expertise and environmental research, TUV NEL has strengthened its team of technology specialists. Building on existing links with universities, a number of engineering graduates have recently joined TUV NEL to expand and enhance its capabilities and skill base, in particular in the areas of energy and emerging technologies.

A mentoring and training programme has been established with the aim of developing these graduates into the experts of the future. This initiative complements the company’s scholarship scheme which provides undergraduates with industrially relevant projects for their degree course, and of course valuable work experience. For more information on our graduate recruitment and student placement schemes please contact us.

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www.flowprogramme.co.uk

Update on metrology and ‘standards’ in Europe The UK has recently moved to a key position to support and develop this process for flow measurement within Europe and internationally by the appointment of Richard Paton from TUV NEL to the position of Chairman of the Technical Committee for Flow (TC-Flow).

www.flowprogramme.co.uk/networks/standards

The role of metrology is vital in supporting world trade and depends on international agreement for consistent standards of measurement. The European Association of National Measurement Institutes (EURAMET) aims to ensure consistency in measurements and standards through comparisons and collaborations between other National Measurement Institutes within Europe.

The International Committee for Weights and Measures (CIPM) allows the worldwide development of international standards leading to measurement consistency across the world. TUV NEL, representing UK, will play an active and key influencing role in the decision-making committee of the CIPM Working Group for Fluid Flow in addition to representing EURAMET TC-Flow. An interesting development within EURAMET is the development of the European Metrology Research Programme (EMRP) to enable focused collaborative R&D projects involving the National Measurement Institutes within Europe.The projects will be large cross-disciplinary collaborative projects to establish infrastructure and solutions to metrological challenges. It is anticipated that the projects will attract significant EU funding. The European flow community is poised to interact and lead development in one of the key funding areas of energy.

2009 Americas Workshop announced TUV NEL has announced plans for its 2009 Americas Workshop. The event builds on the success of the inaugural US based Workshop on Production and Upstream Flow Measurement in 2008 which TUV NEL organised, in conjunction with leading Texas-based organisations, in February this year. The 2009 Americas Workshop will take place on 3 – 5 February in Houston, Texas. The Workshop will be the only major forum in 2009 to address changes and developments in practice and technology that affect North, South and Central America. The success of this year’s Workshop shows that flow monitoring, measurement and management are clearly issues that are high on the industrial agenda. With an increased number of oil companies sharing infrastructure such as platforms and pipelines, it has never been more important to ensure that accurate and reliable metering technology is available. The 2009 Workshop will be a week-long forum including two supplementary training courses and an accompanying exhibition of technology.

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The main content of the Workshop will be technical papers presented by experts from operators, regulators, engineering contractors, service companies and research organisations. These will be supplemented by shorter

www.flowprogramme.co.uk/events

experience-based overviews, providing opportunities to develop engineers. Submissions are anticipated over a broad range of applications and technologies, including metering and production, subsea metering systems, downhole technology, high viscosity fluids, flaring and venting, high pressure/high temperature conditions, PVT, sampling, and performance of 3-phase meters operating in a single or 2-phase environment, and real time data acquisition. More information on the 2009 Americas Workshop and TUV NEL’s events in general can be found by following the Events link on the website.

ISSUE 59 AUTUMN 2008

UK manufacturing benefits from European R&D funds Manufuture and FP7 are two European initiatives to promote manufacturing industry in the EU. Manufacturing is a cornerstone of the European Economy, contributing over €6,500 billion in GDP and providing 20 per cent of all employment. In addition, manufacturing enables Europe to play a vital role in the global economy with over 42 per cent of world-wide manufacturing exports and 18 per cent of global trade volume.

www.flowprogramme.co.uk/projects

Facility for flare gas flowmeter testing TUV NEL has expanded its portfolio of flow measurement services by developing a facility for assessing in-service performance of flare gas flowmeters. This facility has been developed in response to increasing demands on industry to reduce atmospheric emissions and improve the accuracy to which they are measured.

Manufuture is a cross industry European Technology Platform which helps to drive and support innovation, competitiveness and sustainability in manufacturing. TUV NEL is actively participating in Manufuture, in collaboration with the Innovative Manufacturing and Construction Research Centre at Loughborough University and The Welding Institute. The team is promoting the UK’s manufacturing vision to help influence the European Research Agenda (ERA) and drive public sector support for manufacturing across all industry sectors. The Manufuture Technology Platform helps UK manufacturing to speak with one voice and acts as an active network for manufacturing and research organisations across Europe. Manufuture is an important

The emissions experts at TUV NEL are already using the facility to assess the impact of installation effects on ultrasonic meters in flare gas measurement applications. However, the facility has much wider application. The test facility measures air flow at atmospheric pressures with pipework typically in the range 200 to 300mm (8 to 12 inch) diameter, although larger or smaller sizes can be accommodated on request. The facility can accommodate flows from 20 l/s up to 4000 l/s (14,400 m3/hr), depending on pressure drops in the system. It is therefore well suited to testing and evaluating flowmeters and assessing installation effects in flare-gas and other gas flow applications. The uncertainty associated with the measurement of volume flow in this facility is 0.5 per cent. The latest data acquisition and processing systems similar to those in the water and oil National Flow Measurement Facilities mean that it is quick and easy for flowmeters to be set up and results obtained. The facility can be used to assess the performance of a range of flowmeter types with the recommended or with non-standard installations. It can also be used to assess the performance of other pipework components and devices.

www.flowprogramme.co.uk/news

forum for participants to share, learn and develop new business models, and it supports agile manufacturing and sustainability in a non -competitive way. The ERA is supported by the European Union’s Seventh Framework Programme (FP7) for research and technological development. The FP7 Programme runs from 2007 - 2013 and has a budget of over €50 billion to develop or maintain the EU as a world leader in key thematic areas such as Energy, Environment, Nanotechnology, ICT, and Health. TUV NEL manages and delivers the FP7 National Contact Point service within the UK for several of the thematic areas. A recent survey carried out by TUV NEL revealed that 81 per cent of those surveyed reported that participation within the Framework Programme had helped their organisation to grow. This was largely due to formation of new alliances, access to new technology and entrance to new markets or regions.

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EVENTS IN THE PIPELINE

FORTHCOMING MEETINGS

www.flowprogramme.co.uk/events

www.flowprogramme.co.uk/events

Measurement Uncertainty Training Course

Emissions Club

20 October 2008, St Andrews Measurement is fundamental to the control of quality, efficiency and safety. Designed to impart an understanding of measurement uncertainty using examples tailored to the oil and gas sector, delegates will receive practical guidance on the design of measurement techniques for improved uncertainty.

Thermodynamics of Fluid Systems Training Course

20 October 2008, St Andrews This one-day course is intended for those who are new to the thermodynamic behaviour of fluids or who wish to refresh their basic understanding of the subject.

26th International North Sea Flow Measurement Workshop 21-24 October 2008, St Andrews This Workshop is the premier world event where specialist engineers, involved with all aspects of oil & gas production, meet to review flow measurement methods, techniques and advances.

LDT O S OU

9 October 2008, Aberdeen www.emissionsclub.com

Produced Water Club

29 October 2008, Aberdeen www.producedwaterclub.com

Water Industry Flow Club 5-6 November 2008,Telford The Club will be presenting at the WWEM Conference on “Facing Challenges in the Water Industry”. http://wifc.flowprogramme.co.uk

Introduction to Flow Measurement

11-12 November 2008, East Kilbride This two-day training course is intended for anyone who is new to flow measurement or who wants to refresh their basic understanding of flow measurement.

Oil and Gas Focus Group 3 December 2008, Aberdeen http://ogfg.flowprogramme.co.uk

Produced Water - Best Management Practices

26-27 November 2008, Kuala Lumpur, Malaysia This event is designed for those who are concerned with oil & gas production processing, in particular produced water management, treatment and handling.

The Americas Workshop

3-5 February 2009, Houston, USA Following the success of the inaugural event earlier this year, the second Workshop is a major forum for operators, equipment manufacturers and other interested parties such as fiscal bodies, to examine the flow measurement challenges that the oil and gas industry in North, South and Central America face now and in the future.

8th South East Asia Hydrocarbon Flow Measurement Workshop

4-6 March 2009, Kuala Lumpur This Workshop is now established as one of the main events in the region for flow measurement technology. It brings together operators, regulators, equipment suppliers, engineering contractors, service companies and researchers to share information and experience. It is the only major forum to address the changes in flow measurement practice and technology that affect the region.

RECENT PUBLICATIONS www.flowprogramme.co.uk/publications

Parametric Study for Ultra-low Liquid Flow in Micro-conduits Assessment of Calibration and Traceability Requirements for Ultralow Flowrates Application of MEMS Ultrasonic Transducers to Flow Measurement

Principles and Practice of Flow Measurement Course

12-14 May 2009, East Kilbride This three-day course is designed for the engineer who needs to gain a sound knowledge of flow measurement methods, to know how to choose the best flowmeter for a particular need and how to get the best from the meter when in service.

For enquiries on any of the articles please contact: [email protected] Tel: + 44 (0) 1355 593745

®

East Kilbride, Glasgow G75 0QF, United Kingdom Tel: + 44 (0) 1355 220222 Fax: + 44 (0) 1355 272999 www.tuvnel.com

Flow Tidings is a quarterly publication of TUV NEL Ltd, sponsored by the UK Government’s Department for Innovation, Universities and Skills under the National Measurement System’s Engineering and Flow Programme. The articles in Flow Tidings are intended to inform the reader but do not represent the opinion or policy of DIUS and/or TUV NEL Ltd.

EVENTS IN THE PIPELINE

FORTHCOMING MEETINGS

www.flowprogramme.co.uk/events

www.flowprogramme.co.uk/events

The Americas Workshop

Oil and Gas Focus Group

3-5 February 2009, Houston, USA Following the success of the inaugural event earlier this year, the second Workshop is a major forum for operators, equipment manufacturers and other interested parties such as fiscal bodies, to examine the flow measurement challenges that the oil and gas industry in North, South and Central America face now and in the future.

8th South East Asia Hydrocarbon Flow Measurement Workshop

4-6 March 2009, Kuala Lumpur This Workshop is now established as one of the main events in the region for flow measurement technology. It brings together operators, regulators, equipment suppliers, engineering contractors, service companies and researchers to share information and experience. It is the only major forum to address the changes in flow measurement practice and technology that affect the region.

Principles and Practice of Flow Measurement Course

12-14 May 2009, East Kilbride This three-day course is designed for the engineer who needs to gain a sound knowledge of flow measurement methods, to know how to choose the best flowmeter for a particular need and how to get the best from the meter when in service.

Oil in Produced Water Training Course

28 April 2009, Aberdeen This one-day training course will enable delegates to gain a good understanding of the definition of oil-in-produced water, analysis and measurement methods available.

25 March 2009, Aberdeen http://ogfg.flowprogramme.co.uk

Emissions Club

9 April 2009, Aberdeen www.emissionsclub.com

Produced Water Club

1 May 2009, Aberdeen www.producedwaterclub.com

RECENT PUBLICATIONS www.flowprogramme.co.uk/publications

Improvements in the Measurement of Gas Flows with Entrained Liquids Using Orifice Meters

Produced Water Workshop

Application of MEMS Ultrasonic Transducers to Flow Measurement

Produced Water Training Course

The use of Hydraulic Structures for Open Channel Flow Measurement

29-30 April 2009, Aberdeen This event is for interested parties to find out about and keep abreast of the latest technological and legislative developments, as well as current practices and trends in produced water management, treatment and handling. 1 May 2009, Aberdeen This one-day training course will help delegates in their understanding of practices and trends in measurement of produced water.

Measurement Uncertainty Training Course

10 June 2009, Aberdeen With measurement uncertainty underpinning the whole credibility of environmental reporting, this one -day training course is designed to equip industry personnel with the fundamentals necessary for calculating measurement uncertainty.

Oil & Gas Emissions Seminar

11 June 2009, Aberdeen Key environmental legislation places an obligation on energy intensive sectors to report their greenhouse gas emissions effectively. The oil & gas industry faces challenges and difficulties in meeting obligations. This one-day seminar aims to bring industry together to share knowledge to help establish solutions.

For enquiries on any of the articles please contact: [email protected] Tel: + 44 (0) 1355 593745 East Kilbride, Glasgow G75 0QF, United Kingdom Tel: + 44 (0) 1355 220222 Fax: + 44 (0) 1355 272999 www.tuvnel.com Flow Tidings is a quarterly publication of TUV NEL Ltd, sponsored by the UK Government’s Department for Innovation, Universities and Skills under the National Measurement System’s Engineering and Flow Programme. The articles in Flow Tidings are intended to inform the reader but do not represent the opinion or policy of DIUS and/or TUV NEL Ltd.

NATIONAL MEASUREMENT SYSTEM FLOW NEWSLETTER

ISSUE 60 WINTER 2008

Combating climate change - carbon capture and storage With fossil fuels remaining the main source of energy for many decades to come, reducing associated carbon dioxide (CO2) emissions using Carbon Capture and Storage (CCS) technologies is seen as one of the greatest solutions in combating climate change.

Continued on Page 2

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STACK EMISSIONS

www.flowprogramme.co.uk Continued from Page 1

Combating climate change - carbon capture and storage

www.flowprogramme.co.uk/projects

This is reflected in the UK Government’s current stance on CCS and forthcoming legislation which will make CCS compulsory for all new power plants, and CCS provisions (‘CCS ready’) necessary for all new combustion plants. The inclusion of CCS in Phase 3 of the EU Emissions Trading Scheme will also impact on many industrial sectors. A new project within the Engineering and Flow Programme is currently underway at TUV NEL to investigate the measurement issues and challenges associated with the accurate monitoring of CO2 for different CCS applications. It is anticipated that the accurate measurement of CO2 to meet legislative requirements will present many challenges. Several organisations currently engaged in CCS projects and CO2 measurement have identified problematic behaviour of CO2 under high pressure conditions. CO2 is unusual because of the relationship and closeness of its triple point and critical point to the temperature and pressures commonly found in industrial processes. At the pressures and temperatures necessary to pump CO2 into oil fields and for sequestering CO2 from CCS applications, the CO2 is compressed between phases, from a gas to a liquid to a supercritical fluid, where it then behaves in ways analogous to a gas but with densities more associated with liquids. Due to its physical properties it can also undergo rapid phase changes which can make the measurement of flow rate extremely difficult. To date there has been limited experience and information relating to the performance and accuracy of flowmeters in various CO2 phases and transitions. The project, currently underway at TUV NEL, will involve collaboration with industry to identify CCS measurement requirements and needs, and to identify and assess the suitability of existing metering technologies to accurately measure CO2 under given conditions.

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Energy companies recognise the need to define the applicability of crude oil expansions coefficients for a wider range of crude oil density measurements. The need to account for the effects of pressure and temperature on the volume occupied by a given mass of hydrocarbon liquid is a universal one in this industry. Current industry practice is to use three laboratory-derived standards to quantify these effects - API 2540 (which deals with the effect of temperature) and either API 11.2.1.M or IP Paper 2 to account for the effect of pressure. There is growing awareness within the upstream oil and gas industry that these standards were derived from the analysis of a fairly small set of crude oils, the condition of which was not particularly representative of the crude oils encountered in typical applications in the North Sea and elsewhere. The crude oils tested had been allowed to stabilise, and were comparatively (or completely) dry. In contrast, most measurement systems in the upstream sector operate on ‘live’ crude with sometimes significant water content. A new TUV NEL Joint Industry Project (JIP) will investigate the significance of these differences. The more a crude oil differs from the ‘test’ crudes, the more its ‘true’ pressure and temperature coefficients will differ from the generic ones determined by the API and IP standards. The effect of the use of generic coefficients will therefore vary from field to field. However, in view of the increasing water cuts of many

ISSUE 60 WINTER 2008

Research on crude oil expansion coefficients

NEWS

Further details on any of our News items and links can be found at www.flowprogramme.co.uk/news

■ The Engineering & Flow Programme welcomes industry input to help with the formulation of the 2009 Programme. Register your contribution on the website or contact TUV NEL. ■ The Technology Strategy Board has just (January 2009) launched a new research & development competition for funding entitled “Maximising Recovery of UK’s Oil & Gas Resources”. ■ Information on the winners of The Energy Institute Awards, with categories including innovation, communication, environment and technology, is available on the website. ■ The Institution of Engineering and Technology (IET) Innovation Awards for 2008 have been announced. See website for more information.

www.flowprogramme.co.uk/projects

mature assets in the North Sea and the advent of High Temperature/High Pressure fields, these generic coefficients are likely to be less representative than ever before. This JIP and the Traceable Density Measurement JIP are excellent examples of Government departments and industry working together to solve generic industry issues. DIUS’s Engineering and Flow Programme provides the underpinning support for the facilities. Industry commitment will ensure that proposed solutions are tailored to specific needs; a number of companies have already indicated significant interest in collaborating on this project. Potential Misallocation

■ The 9th Advanced Power Technology Forum Workshop on “Carbon abatement technologies for fossil fuels: Development and implementation of future UK strategy” will take place on 11-12 February, London. ■ Final report by TUV NEL on international key comparison of liquid hydrocarbon flow facilities is available from Metrologia.

for a 2°C difference between flowmeter and densitometer (densitometer at 50°C and 30 bar) 4.0

■ OTC (Offshore Technology Conference), the premier world offshore industry event, takes place from 4-7 May in Houston, Texas.

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North Sea Workshop a sell-out success Europe’s largest gathering of oil and gas industry flow metrologists took place recently at the International North Sea Flow Measurement Workshop in St. Andrews. The sold-out, four day event involved more than 300 delegates from across the globe. The TUV NEL organised event focused on the challenges facing flow metrology and presented delegates with an opportunity to set an agenda for future flowmeter technology development. The proven formula of technical and poster presentations from major producers, gas distributors and equipment suppliers from across the globe combined with networking events and opportunities, and JIPs focusing on industry critical issues ensured a thought-provoking and inspiring programme. In addition, the event was preceded by two optional courses allowing attendees to benefit from training on measurement uncertainty or thermodynamics of fluid systems.

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Papers were presented on key flowmeter topics including complex well metering, the application of Coriolis and ultrasonic meters with viscous flow, the challenges of multiphase flows, the impact of pressure and temperature on flowmeters, computerised allocation systems and the measurement of wet-gas. The 2008 Best Paper Prize was awarded by the Technical Committee to Phillip Stockton of

Smith Rea Energy Limited for his paper entitled “Features of Allocation Systems Incorporating Long Pipelines.” Presentations and subsequent discussions allowed the exploration and examination of various new and potential flow metering technologies and their in-field application, with field performance data featuring highly at the event. Key themes emerging from the Workshop included discussions on a robust methodology for geometry related pressure and temperature compensation for gas ultrasonic flowmeters, the effect of high viscosity oils on single and multi-phase metering technologies, new selfdiagnostic techniques for metering technologies and the benefits, challenges and limitations associated with the deployment of multiphase meters in complex applications. In addition, allocation systems received worthwhile and overdue attention. The need for forward thinking and continuous improvement in the flow metering industry was expressed by a number of the delegates. The Workshop presented an ideal forum to consolidate and help ensure flowmeter research and technology development is aligned to industry needs. The effective utilisation of forums, such as the North Sea Flow Measurement Workshop, improves understanding and assists in the evolution of this critical industry sector. The 2009 Workshop will take place in Norway, with the UK hosting again in 2010.

ISSUE 60 WINTER 2008

Ultrasonic flowmeter pressure and temperature corrections In ultrasonic flowmeters, operating at pressure and temperature conditions that differ from the calibration conditions introduces two sources of error: firstly, a path velocity error and secondly, a flow area error. Geometry related pressure and temperature corrections (i.e. ones that correct for meter body growth or shrinkage) have been applied for a number of years to different types of flowmeters but with little consistency between reference documents and lack of traceability in the actual formulae used. If uncorrected, these errors introduce a bias error in the metered flow rate. TUV NEL has used a first principles, traceable approach to develop a simple method of estimating the magnitude of these pressure and temperature corrections for any body type and has presented this in a paper at the 2008 North Sea Flow Measurement Workshop. The method allows the severity of the likely error to be assessed against given meter

categories and allows the user to make an informed decision as to whether or not more detailed modeling, for example Finite Element analysis, is justified. The method is incorporated in full in the recently released ISO/DIS 17089-1 (Ultrasonic metering of gas at fiscal and allocation level) and as a first-level check in the imminent revision of BS 7965 (Ultrasonic metering for industrial gas applications).

www.flowprogramme.co.uk/projects

Challenges of heavy oil Heavy oil and multiphase meters were high on the agenda at this year’s North Sea Flow Measurement Workshop. The challenges of heavy oil metering and the investment being made to develop and test both single and multiphase meters needed for future heavy oil production were described at this year’s North Sea Flow Measurement Workshop. Upstream metering in heavy oil applications faces a number of technical challenges. Traditional test separators for example are difficult to operate at the higher viscosities involved due to vessel instability, foaming and separation issues. In addition, retention times are often higher, and emulsion formation more likely, while the inclusion of trapped gas bubbles inside the liquid phase can lead to the over estimation of liquid volume flow rate. As a consequence, many industry experts believe that the future of heavy oil measurement will rely heavily on multiphase metering. Research, including the TUV NEL Joint Industry Project focusing on the effect of high viscosity oil on single-phase meters, and a Technology Programme collaborative project focusing on higher viscosity multiphase flow effects, is currently underway.

www.flowprogramme.co.uk/projects

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www.flowprogramme.co.uk

CFD at the extremes TUV NEL is continuing to build capability and experience in applying CFD to industrial problems. CFD skills are combined with engineering and fluid dynamics knowledge to generate solutions in extreme applications. To date, CFD has been effectively employed in a variety of areas including multiphase and wet gas Venturi meters, drain holes, installation errors, plate reversal and contamination in orifice plates, and water purification. It has been used on very large and very small scales from hot air blowing over a process plant to microfluidic channels. www.flowprogramme.co.uk/networks/standards

TUV NEL demonstrates how faster computers are making CFD simulations of increasingly complex problems viable. Recent projects highlight the contrasting and extreme conditions to which CFD can now be applied.

Currently, TUV NEL is using CFD to assess insulation requirements for subsea wellheads 1200m underwater. However, recent simulations have modelled flows as deep as thousands of metres under the ground and have been used to assess erosion in valves and sand screens in highrate gas wells. In the near future CFD simulations involving multiphase flows, fluid-structural interaction, moving boundaries and multiphysics will become commonplace. TUV NEL is actively engaged in assessing how best to apply these techniques to provide a wide range of engineering solutions.

Ground-based wind speed measurements Assessing the likely annual energy yield is an important step in the selection of a suitable location for the development of a new wind farm. Site terrain can be complex and, conventionally, wind speed data are gathered using a number of cup-type anemometers mounted on a tall mast. This can involve a lengthy planning and installation process. Also, the mast has to be left in position for long enough to enable a reliable estimate of the site’s annual wind energy yield to be obtained. Two ground-based measurement technologies have been developed for measuring wind speeds over a range of heights above ground level: • Sound detection and ranging (SODAR) • Light detection and ranging (LIDAR) Before these instruments are likely to be accepted as an alternative to cup-type anemometers, their performance relative to these has to be verified. This has been accomplished by TUV NEL in a recently completed measurement campaign at its Myres Hill wind turbine test site in which SODAR and LIDAR measurements were compared with data from nine anemometers positioned on an 80 metre mast.

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The results of this international project will be used to demonstrate the application of SODAR and LIDAR instruments in the wind energy sector.

www.flowprogramme.co.uk/news

ISSUE 60 WINTER 2008

Metrology challenges in microfluidics systems

Accurate measurement of stack emissions www.flowprogramme.co.uk/projects

Microfluidics is enabling organisations to have enhanced control over fluid conditions in addition to the numerous other benefits associated with working at small scales. However, use of this relatively new technology has introduced new challenges.

Expertise and Capability for Microfluidic Systems Analysis

Emmelyn Graham and Norman Glen, TUV NEL, Scotland Computational Fluid Dynamics (CFD)

• Expertise in fluid modelling for microfluidic systems using commercially available packages including Comsol and Fluent • Assessing capability and suitability of commercial packages for microfluidic applications • Extensive validation of commercial packages against experimental data • Identifying limitations of packages • Provide modelling solutions and identify areas for further research

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Contours of mass fraction on slices through a T-mixer at 10 µl/min

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Predicted methanol mass fraction on slices through T-mixer at a flowrate of 10 µl/min: a) gravity off, b) gravity on and 75 µl/min: c) gravity off, d) gravity on

Heat Transfer and Thermophysical Properties

Experimental Validation Expertise

• Accurate predictions of a range of key parameters required in fluid modelling using specialised software (PPDS) developed and maintained by TUV NEL for industrial process chemistry applications • For mixtures of fluids data provided includes – – – – –

fluid viscosity density thermal conductivity heat capacity data uncertainty bands

• Expertise in advanced fluorescence imaging techniques including Fluorescence Lifetime Imaging Microscopy (FLIM) – in full field imaging using epifluorescence microscopy – confocal imaging to provide 3D optical sectioning • Quantitative mapping of fluid composition for evaluation of mixing efficiency within commercial micromixers • fluid temperature distribution within microfluidic systems • Micro Particle Imaging Velocimetry (Micro-PIV) to map and quantify fluid flow characteristics within devices

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• Experience of heat transfer analysis and interpretation

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Design Optimisation Capability

Ability to evaluate and optimise the designs of microfluidic systems using existing capability and expertise in fluid flow modelling e.g. CFD, fluid properties database, heat transfer etc.

• Extensive experience in fluid flow measurement and calibration for liquid and gas flows • Collaborations and extensive flow research networks within Europe through EURAMET (European Association of National Measurement Institutes) Technical Committee of Fluid Flow and worldwide contacts • Primary flow measurement standards for the UK

FLIM has been used to monitor the mixing of MeOH and a H2O/MeOH mixture over a range of flowrates and positions in a simple T-shaped micromixer.

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Flow Measurement Expertise

FLIM technique

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         mixing of wo solutions in a microfluidic system

Research and Reviews

Swirl through pipe bends

Publications

• Quantitative spatial mapping of mixing in microfluidic systems, Angew. Chem. Int. Ed. 2005, 44, 6512 –6516 • Quantitative comparison of thermal and solutal transport in a T-mixer by FLIM and CFD, Microfluid. Nanofluid. 2008, 5, 603-617 • A study of diffusive mixing in a microfluidic T-mixer device using commercial CFD modelling packages, submitted to J. Micromech. Microeng. • Traceable flowrate measurements for microfluidic systems, Proceedings of ICNMM2008 Conference

• Assessment of calibration and traceability requirements for ultra-low flowrates – assessed the need for traceable ultra-low flowrate measurements covering microfluidic applications in both academic and industrial environments within the UK • Parametric study for ultra-low liquid flow in micro-conduits – highlights and explains key computational issues associated with CFD simulations of liquid flow in micro-conduits • Review of fluid flow in microfluidic devices – review of the current state of the art in relation to knowledge, experience and measurement of fluid flow in microfluidic systems. • State of the art review of microfluidics – individual reports produced in 2006, 2007 and 2008 covering advancements and metrology challenges within microfluidic related areas

To identify these emerging issues and barriers to the use of this technology a highly successful one-day Metrology for Microfluidics Workshop was held recently by TUV NEL on behalf of DIUS in Loughborough. Over 40 UK and international delegates from industry and academia attended the event and actively contributed to discussion sessions to identify the current and future challenges. Presentations covered the fundamental design, measurement and manufacture of devices through to the end applications driving the technology. A report summarising the challenges and issues identified is available from the website.

The accurate measurement of emissions from industrial stacks is necessary to monitor harmful pollutants and to comply with environmental legislation, such as the EU Emissions Trading Scheme and IPPC Directive. Pitot tubes are commonly used in emissions monitoring to determine gas flow in the stack. Although cost effective and relatively simplistic in design and installation, the Pitot tube has a very limited range of operation where it can be used with an acceptable level of confidence. Furthermore, laboratory calibrations which are carried out at single point and under perfect flow conditions, are generally not comprehensive enough or representative of the true conditions found in stacks. Previous studies have indicated a need for further research into the use of Pitot tubes for stack emissions monitoring applications to validate performance and accuracy when used outside the accepted range. TUV NEL has recently initiated a study to investigate these issues. This will include evaluating a wide range of representative stack conditions using computer modelling and analysis software to assess how various flow conditions impact on measurement uncertainty. The work will provide better insight into the flow measurement issues surrounding Pitot tubes and help establish useful reference data and correction factors to assist industry in emissions measurement calculations. If you are interested in contributing to this review, please contact TUV NEL.

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