The new Advanced Multiphase Facility will provide cutting-edge facilities necessary to address the technical challenges of extreme subsea operating conditions. The facility is a pressurised, closed loop flow circuit that offers a range of operating conditions for single-phase, multiphase and dry gas test applications.

Glasgow-based TÜV SÜD NEL, which provides flow measurement standards for the UK’s National Measurement System, began constructing the base building that will house its £16 million Advanced Multiphase Facility (AMF) in September 2017. Building work was completed in May 2018, and an extensive fit-out has commenced since.

Scottish Enterprise has supported the development of the AMF with £4.9m. Alongside the grant, TÜV SÜD NEL’s parent company, TÜV SÜD AG, is investing £11.1m –  the largest capital investment to date in the company’s UK business. The facility will span 1,600 m2, and contain a £1.45 million, full production scale separator, with an operating weight of 270 tonnes and operating at pressures up to 150 bar. The facility will be capable of calibrating and verifying flow meter performance, ranging from 2in pipe, up to more than 14in.

“This is by far the most unique facility relating to fluid mechanics research, enabling flow rates that are 20 times greater than the performance of any other test facility in the world,” says Anna Pieper, multiphase flow leader at TÜV SÜD NEL. The facility will allow testing at wide-ranging flow rates under high operating pressures and temperatures. Most importantly, it will allow the evaluation of meters at the conditions in which they are used in the field.  

The centre will focus predominantly on the £50-billion-per-annum global subsea sector, production, and wet gas business. It will facilitate company-led industrial projects and product development, hands-on industry training, and academic research. The facility will also undertake dry gas calibration work.

The organisation already has a comprehensive range of flow testing facilities at the campus. “The new facility will augment these, offering research facilities and a breadth of capability unmatched anywhere else in the world,” adds Pieper. “It will also support Scotland’s oil and gas sector to maximise its global competitiveness and position Scotland as a global leader in multiphase flow measurement. The North Sea is also the home of the most advanced technologies used in challenging conditions offshore. Aberdeen is within reach, and is the capital of the oil industry in the UK.”

Addressing challenges

In the current climate of minimising production costs and ensuring that production remains economically viable, the measurement of multiphase flows is a key factor in understanding the performance of production operations and improving the recovery factor.

“Significant remaining production opportunities are to be found in extreme environments with higher operating pressures and temperatures,” explains Pieper. “These conditions can impact significantly the performance of multiphase flow measurement devices, and this needs to be properly quantified or demonstrated to government authorities to ensure there is no bias in the production and taxation process. TÜV SÜD NEL is a playing a key role as a fair and impartial arbiter.”

AMF will support current and future measurement challenges, from well optimisation production to fiscal accounting and reservoir management. The facility, with additional high pressure and high flowrate capabilities, is built for a range of services. These, according to Pieper, include single phase calibration or meter verification; multiphase and wet gas testing, seamlessly, from one domain to the other (put simply, from oil wells to gas wells and everything in the boundary zone); research into flow measurement and flow regimes; and understanding flow structures using novel research techniques. The facility is also built for technology development; supporting SMEs; largest multiphase flow rates in the world for the combination of gas, oil, and water; and impartial, and independent laboratory certified ISO17025.

The services are aimed at a range of audiences, including:

● Oil and gas companies who are end-users of flow metering equipment and who require accurate measurement;

● Governments who wish to ensure that taxes are paid correctly and fairly;

● Multiphase solution developers needing validation/performance certification;

● Universities developing software and who require flow modelling understanding;

● And engineering, procurement and construction firms that build entire structures, and wish to select appropriate equipment and ensure it meets specifications.

To the future

Two joint industry projects (JIP) and one joint research project (JRP) have already been initiated and will take place in the AMF. Current projects include:

● JIP: Oil & Gas Industry Verification of Flow Meters and The Use of Such Equipment – the financial exposures for oil/gas firms means that they have to ensure, validate, and rank products on the market. The right meter needs to be selected from day one.

● JIP: Water Cut Meter Performance – this is a recurring issue in oil and gas companies, with roughly 3.5 times more water than oil produced. There is a cost associated process and dispose of the water.

● JRP: Flow Mapping, Flow Structure, and Flow Regimes – as the oil and gas industry moves towards digital solutions, this requires a greater understanding of fluid mechanics and flow structures and how to model them.

“There will also be opportunities for universities to access the facility through collaborative work, which can help to improve understanding of fluid mechanics, and modelling and software development,” concludes Pieper.

Main equipment on site


● The gravity separator is a horizontal, cylindrical pressure vessel with specialist separation internals. The main body is 33m long. Its internal diameter is 2.6m, with a 10m inlet pre-stratification section. The operating weight is 270 ton and pressurised permanently to 150 bara. The size allows for a very large retention time and proper separation of the three phases: oil, water, and gas (technical specifications at www.is.gd/najexa).

● Each liquid stream has two identical inverter-driven centrifugal pumps provided by Pumping Technical Services to allow more than 83,000 bpd (barrel per day) for each line.

● The gas line is equipped with two large blowers, with capacity reaching up to 350MMSCFD (million standard cubic feet per day) of gas.

● The entire facility will require more than 3MW power when at full capacity. This requires a large heat exchanger to cool down the fluids and keep them within a range of 15°C to 45°C.

● The main liquid flow references are Coriolis meters, with each stream comprising four parallel meters of ascending size. The gas reference section is constructed with two ultrasonic meters and two Coriolis meters, again all in parallel, and of various sizes to provide full flow range.

● Liquid thermal conditioning is provided by slipstream recirculation of the water and oil bulk volumes from the separator through dedicated shell and tube cooling heat exchangers, and electrical heating units. Gas cooling is carried out using an in-line shell and tube aftercooler.

● The piping system is generally of carbon steel construction with ANSI class 900 flanges, switching to stainless steel of the same rating for the two test sections (6” and 10”). A large manifold is present to ensure the relevant mixing process in one of the two permanently mounted lines. The piping can be changed to accommodate any equipment with pipe diameter from two to more than 14in.

● The supervisory system data acquisition software is TÜV SÜD NEL FlowStudio. It records pressure, temperature, and flow, among other information at multiple points. An Air Products liquid nitrogen plant provides pressurised gas to the loop.

 

By Adam Offord