Development of system for semi-continuous monitoring of salinity in well streams to remove volume measurement errors and detect water breakthrough

Información del proyecto

SALINITYSCAN

Identificador del acuerdo de subvención: 262646

Proyecto cerrado

Fecha de inicio 1 Enero 2011

Fecha de finalización 31 Marzo 2013

Financiado con arreglo a

• Specific Programme "Capacities": Research for the benefit of SMEs

Coste total € 1 445 007,60

Aportación de la UE € 1 131 294,00

Coordinado por

TEKNOLOGISK INSTITUTT AS
Norway

Final Report Summary - SALINITYSCAN (Development of system for semi-continuous monitoring of salinity in well streams to remove volume measurement errors and detect water breakthrough)

Executive Summary:
Development of system for semi-continuous monitoring of salinity in well streams to remove volume measurement errors and detect water breakthrough

Salinityscan – an FP7 Project

The idea behind the Salinityscan project, finalized in March 2013, was to develop a subsea sampling and analysis system capable of monitoring the salinity of produced water, thus greatly improving well management and reducing errors in subsea flow measurement. The project has developed a sample and analysis system for installation upstream from MPFMs on subsea manifolds. Integrated in the flow line, the system can sample the multiphase production from the well, allow the fluid to separate into its single phases by electrostatic coealescing and measure the salinity of the water fraction.

Technological challenges addressed by Salinityscan
Multiphase flow meters (MPFMs) are used in the oil and gas industry to measure the individual phase flow rates of oil, gas and water produced during oil production processes. Most MPFMs are based on technology that is heavily influenced by variations in salinity. Thus, variations in salinity may cause erroneous flow rate data, which causes suboptimal well management and less-effective topside processing of the multiphase flow. The SalinityScan system is intended to be integrated in the multiphase flow line from a single well, upstream from the flow meter, where it will sample the flow at user-defined intervals. The sample is separated into its individual phases using an electrostatic separator, and the separated water is analysed. An ultrasound level sensor is implemented to gauge the gas/water/oil volume fraction. Production flow is maintained through a bypass to prevent production stops. The SalinityScan data will be used to update the flow meter calibration parameters, thereby removing the offset caused by the change in salinity. Additionally, by semi-continuously monitoring the salinity it becomes much easier to detect water breakthroughs, which occur when the well starts to produce seawater that has previously been injected into the well to increase pressure or water that has penetrated the oil-carrying layer in the reservoir. By measuring the early onset of formation-water production, as a result of water breakthrough, the operators can take preventative or remedial action, such as injecting the right amount of corrosion inhibitor or, more drastically, choking the well or instigating zonal isolation2. All wells will, as they mature, start to produce increasing amounts of water, but by increased instrumentation, of which monitoring the salinity is an important part, it is possible to keep these wells in operation for longer, thus increasing profits.


Summary of industry benefits gain through the SalinityScan system
- Reduction of errors in multiphase flow measurements induced by variations in produced water salinity
- More efficient use of chemicals used to curb corrosion and scaling by adjusting inject amounts to salinity level of produces water
- Provide reference data on liquid fraction volumes for verification of MPFM data
- Earlier detection of water breakthrough

The SalinityScan project was initiated in answer to the lack of instruments providing this kind of functionality available for installation on existing MPFMs.

Project Results:

• Analysis chamber capable of:
 Separating multiphase fluid
 Measuring salinity
 Measuring volume of phases
• Test system simulating analysis chamber in use, all fitted in a small container for portable presentation

Industrial Participants:

• Tool-Tech AS, Norway (SME)
• Euro Technique Industries, France (SME)
• Intelmec ingeniería S.L Spain (SME)
• SubC Solutions AS, Norway (SME)

R&D Institutions:

• Teknologisk Institutt AS, Norway (RTD Performed & Coordinator)
• Fraunhofer IGB, Germany (RTD)
• Robert Gordon University, UK (RTD)

Finacial support: EU FP7 Research for the Benefit of SMEs
Duration: 27 months
Start Date: January 1st 2011

Further information:

Jon Sletvold, Group Leader, Teknologisk Institutt as
Phone: [phone]
Email: [e-mail]

Or visit our website www.salinityscan.com

Project Context and Objectives:
The objective of the SalinityScan project was to develop a subsea sampling and analysis system capable of monitoring the salinity of the water fraction in the multiphase flow from oil and gas wells. Enabling sampling of the salinity will increase the accuracy in subsea flow measurements and consequently improve well management.

The present-day solutions for monitoring subsea multiphase flow are insufficient for the growing subsea instrumentation market. In response to this, it was proposed to develop a novel sampling and analysis system for installation with multiphase flow meters (MPFM) subsea, which would provide reference data for flow meter calibration and verification of flow data, particularly focusing on measurement of produced water salinity, a known cause of flow meter measurement offsets. The Salinitysscan solution is based on the development of an analysis chamber with built-in coalescent functionality, equipped with level measurement and salinity sensors for analysis of the separated multiphase fluid. An extensive control system has been designed for operating the sampling and release operation. The system shall provide end user with an easy way of ensuring increased flow assurance and enabling further improvement to well exploitation.

Multiphase flow meters (MPFMs) are used subsea to measure the individual flow rates of oil, gas and water in the well stream. Most MPFMs are based on technology that is heavily influenced by variations in salinity. Thus, variations in salinity may cause erroneous flow rate data, which causes suboptimal well management and less-effective topside processing of the multiphase flow.

The SalinityScan sampling system is integrated in the multiphase flow line, where it will sample the flow at user-defined intervals. The fluid is separated into its single phases and the salinity of the water fraction is then measured. The SalinityScan data is used to update the flow meter calibration parameters, thereby removing the offset caused by the change in salinity. Additionally, by semi-continuously monitoring the salinity it becomes easier to detect water breakthroughs. Water breakthroughs occur when the well starts to produce seawater that has previously been injected into the well to increase pressure or water that has penetrated the oil-carrying layer in the reservoir.
Further application of the Salinityscan technology is investigated using measurement of salinity as a tool for determining the need for injection of chemicals (MEG) to inhibit hydrate formation.

The overall project objective was to develop a prototype of the SalinityScan sampling and analysis system by developing an analysis chamber with built-in coalescent functionality, equipped with level measurement and salinity sensors for analysis of the separated multiphase fluid as well as a control system for operating the sampling and data collection. A test setup to show the proof of principle of the system has been built at TI’s Gas Centre in Haugesund. The goal was to test the principle on land under dry conditions. Any subsea test had been out of scope for the project resources available.

The milestones reflect the most important success criteria for project:

MS1: Functional requirements established
MS2: Completion of coalescent unit
MS3: All subcomponents integrated into one test setup
MS4: Verified proof of principle for SalinityScan system by testing of system

The main project objectives were:

Scientific objectives
• Enhanced understanding of electrostatic coalescing and its use in offshore separation of oil and water?
• Understanding of ultrasound level measurement procedures and principles to be used in gauging single phase volumes in analysis tank
• Extensive knowledge of requirements and regulations related to subsea instrumentation and processing of multiphase fluid.

Technological objectives
• Design and construction of electrostatic coalescing unit capable of efficient separation of oil and water under high pressure
• Development/modification of sensors fulfilling system requirements for accuracy in salinity, level, temperature, pressure and other measurements
• Development of control system able to control valve functionality and coealsing unit, while reading data from all sensors in the system

• Development of analysis chamber for use under pressure, housing coalescing unit and instrumentation required for separation and characterising multiphase fluid.
• Successful integration of subcomponents and subsequent testing



Project Results:
The result and foreground is closely related to the work performed under the different work package comprising the work plan of the project. The main results and foregrounds are described in the following:

Functional Requirements
The process of defining the functional requirements for SalinityScan was led by Teknologisk Institutt. However the whole consortium participated actively in the process that led to the final list of requirements for the product. In the initial phase of the project it was not possible to set a specific requirement and values for all parameters. When it was not possible to set a specific value on the parameters it was concluded on a statement e.g. electrostatic coalesce need to fit the analysis chamber perfectly. In the process of defining the functional requirements, the SalinityScan system was assessed on a component by component basis:

a) Electrostatic Coalescent,
b) Analysis chamber,
c) Control System,
d) Salinity measurement sensors,
e) Level measurement and
f) Test setup.

Results:
a) Electrostatic Coalescent: The coalescent unit separates the water from the oil. The electrostatic coalescent unit is integrated in the analysis chamber and it was therefore important that it fitted perfectly.

b) Analysis chamber: The chamber is designed to bypass a choke valve on the subsea manifold, thereby being part of the flow line without demanding large modifications subsea when installing the system. The physical specification of for the analysis chamber is that the volume should be between 10 litre and 70 litre. The target was to minimize the volume of the analysis chamber. See deliverable 1.1 for details.

c) Control system: A PLC based control system ensuring a robust and reliable solution during validation has been developed. The control system controls inputs and outputs necessary for operation of valves, activation of coalescent and reading of sensors.

d) Salinity measurement sensors: The analysis chamber contains sensors for measuring the salinity of the water content in the multiphase flow.

e) Level measurement sensors: It was originally planned that ultrasound should be used for level measurements. However, it was concluded later on that ultrasound would not be the best option for the SalinityScan system. Further work was done by investigating a radio-based Time Domain Reflectometry (TDR) sensor.

f) Test setup: The most complex and costly part of the project was the test setup, into which the analysis chamber and all other components was placed in order to verify the proof of principle of the SalinityScan concept. It was the specification of this part of the work that took the most time and resources in the specification phase of the project. It was concluded by the SME partners that they would gain any additional results by doing submerged testing. In submerged testing the prototype unit would have been placed in a system in which there was pressure applied both outside and inside the analysis chamber. However as it is only the internal pressure that influences the performance of the system a submerged test would not give any extra value to the test results. It was agreed in the consortium that the economic resources in the project should be fully concentrated on dry test where it was only the inside of the chamber that is pressurized.

The basic principle of the test system is to create a flow loop using a circulation pump, thus creating a controlled flow through the analysis under test. Crude oil is supplied from accumulators as necessary. A pressure difference across the analysis unit is created to simulate the differential pressure across a choke valve. Pneumatic controls are used where possible to reduce the gas hazard. An inlet valve for MEG for flushing the system after use was included. The flow loop was intended for circulation of crude oil at 210 bars of pressure. At these conditions, condensate is in liquid form and highly flammable if released to atmospheric conditions. The hazardous gas requirements for the SalinityScan test system have been thoroughly evaluated.

Multiphase Separations
Fraunhofer carried out a literature study aimed to define a technological framework, based on coalescence mechanisms, able to separate diverse water-crude oil emulsions. The objectives were outlined to: a) investigate the strength of electrocoalescence mechanisms in comparison with other techniques and its suitable degree of application on subsea conditions; b) check whether the gravel/sand content bring about concerns to the electrocoalescence unit performance; c) define the optimal electric field supply related to the highest degree of process efficiency and d) identify an optimal technological solution which picture a suitable liaison between complexity and performance of the further developed system.

Results:
a) For the breakdown of water/oil emulsion and further separation, various kinds of mechanisms have been revised such as: chemical, electrochemical, thermal, physical (enlisted as means for breakdown of emulsions) and skimming, filtration/decantation, sedimentation, centrifugation, flotation (enlisted as means for water/oil phases separation). Due to subsea limitations, physical mechanisms coupled with sedimentation were found to be the appropriate process for this application. Within physical mechanisms, along liphophilic materials, adsorption, flotation, ultrasound, microwaves, and freezing/thawing, electric field proved to be the best alternative to the given boundary conditions both in terms of process efficiency and operational difficulty and costs.

b) Solid matters like sand, silt, shale particles, crystallized paraffin, iron, zinc, aluminium sulphate, calcium carbonate, iron sulphide and similar materials can act as emulsifiers, inhibiting the coalescence of the dispersed phase. Considering these, carried out laboratory tests on the further designed electro coalescent unit in order to define the extent of influence of gravel/sand upon its performance.

c) The dominant influence on water/oil phase separation relies on electrostatic coalescent design (together with electrode design). The design has to exploit efficiently the electric field mechanisms and it must be appropriate to the given operational circumstances. Other electro coalescent factors are: fractional volumetric hold-up of dispersed phase, type of applied electric field (DC and AC and pulsed AC and pulsed DC), applied frequency, application time, type and concentration of surfactant. Coalescence rate improves as the applied field strength is increased. Typically electric field strength of 100 kV/m was applied. The coalescence rate can as well be improved as the applied frequency is increased. The maximum value suggested was 1 kHz. Increasing pulse DC duration increased the coalescence rate, if pulse interval was constant.

d) Apart from understanding theoretically the strength of electric field application, its functionality was as well tested in a preliminary designed laboratory scale set-up. In comparison with the separation by gravity, the output by this preliminary test had a better quality and resulted in much less process time. Together with this early experiment, electro coalescent factors were delineated clearly in: a) operational such as electric field strength (kV/m), type of applied current (DC and AC and pulsed AC and pulsed DC), operational volume, emulsion making (by stirrer or ultrasound) and b) process such as emulsion content (water/crude oil fraction, salinity (g/l), type and concentration of chemicals), emulsion stability (defined by water cut volume %/ time, droplet sizes), crude oil properties (density, viscosity). Given the diverse interrelationships between the two categories of parameters, electro coalescent unit design must cope with a complex operational framework. A good performance of the electrostatic coalescent requires firstly to understand the complexity of operational and process interrelationships, and secondly, to apply efficiently the electro coalescent mechanisms within the developed unit.

Level Measurement

RGU did carry out a review of different sensing mechanisms for salinity and fluid level measurements. The methods used for level and interface level measurements in the oil industry are limited because of the request on high reliability, variety of multiphase fluids, harsh environments and intrinsic safety issues. The environment for level sensors varies from vacuum to high pressure and from below zero Celsius degree to high temperature. Because of the involvement of different situations, many types of level sensors have been developed over time. The following level and interface level measurement methods were identified as the most promising for SalinityScan.

The suitability of these different methods was thoroughly assessed.
a) ULTRASONIC,
b) VARIATION IN HEAT TRANSPORT,
c) CAPACITANCE,
d) GAMMA RAY SENSORS,
e)MICROWAVE/RADAR both GWR[Guided Wave Radar] and Non-contacting radar

Results:
a) ULTRASONIC: The advantages are that it is non-intrusive and easy to install on existing and new separators, and no calibration is needed. This system is in commercial use. The disadvantages are that it has difficulty in monitoring emulsion and foam. Also, the presence of gas bubbles in the liquid attenuates/scatters the ultrasound waves. It becomes a big problem when a significant amount of solution gas is present in the liquid. The presence of sand and debris also causes problems.

b) VARIATION IN HEAT TRANSPORT: Thermal measurement involves measuring of different thermo-dynamic properties of the liquid surrounding a thermal sensor. This type of sensor can be intrusively present in the salinity scan chamber. The inner part of this system, which consists of a rod, is kept at a constant temperature by continuously circulating a liquid with temperature control. The disadvantages of this technique are intrusiveness and involvement of the continuously circulating liquid which makes its application in the SalinityScan difficult.

c) CAPACITANCE: There are two basic types. One is based on measuring the capacitance between electrodes, and the other is based on measuring the capacitance between an electrode and infinity or a separator wall. Measurements are usually limited to a couple fluid levels. To overcome this problem, Multi-electrode capacitance level sensors were developed. With this method sharp interfaces can be easily identified. One problem associated with this method is that if a detection electrode is merged in a highly conductive liquid, such as saline water, short circuit to the electrode would happen because of the high conductivity.

d) GAMMA RAY SENSORS: A typical example of a commercial device is the Tracerco Density Profiler. This system is easy to install. Since it has no moving parts, essentially no maintenance is required. The Geiger detectors are rugged and can be useful in measuring the vertical distribution of the various phases in a vessel. Also, it gives information regarding inter-phase mixing. The disadvantage with the nucleonic type interface level sensor is the presence of hazardous nucleonic radiation.

e) MICROWAVE/RADAR
- GWR[Guided Wave Radar]
- Non-contacting radar
Microwave is a new method for simultaneous and independent on-line determination of bulk density and content in particulate and fluid materials by measurements of the relative complex permittivity.
Both the Guided Wave radar technique [GWR] and the Non-Contacting Radar (NCR) technique are based on the principle of time domain reflectometry (TDR). With GWR, a low-energy electromagnetic pulse is guided along a probe. When the pulse reaches the surface of the medium being measured, the pulse energy is reflected up the probe to circuitry that then calculates the fluid level based on the time difference between the pulse being sent and the reflected pulse received. The NCR technique functions in much the same way, but without the probe.

The recommended level measurement sensors types in order of priority are:
a. Option 1 ; Non-Contacting Radar[ Based on Dielectric Constant Principle]
b. Option 2 Guided Wave Radar Transmitter
c. Option 3: Multiple Electrode Capacitance
Option 4: Non-Intrusive Ultrasonic

Related deliverable: D1.2 Investigations into level measurement and electrostatic coalescing


Design of Multiphase Separation Unit

In Work package 2, Fraunhofer carried the following tasks: a) design and construct an electro coalescence unit capable of separating efficiently diverse water-crude oil emulsions under the functional requirements given in Tasks 1.1 Task 2.2) test the built unit to optimising its performance considering various types of emulsions, Task 2.3) finalize a design suitable for integration with the analysis chamber.

Results:
Three concepts for the electro coalescing unit were designed and tested considering the electrodes design, namely: cylindrical reactor with electrodes in horizontal position, rectangular reactor with electrodes in vertical position, cylindrical reactor with electrodes in concentric position. The operational volume was fixed to 1,5 litres. Various fundamental tests were performed in order to decide upon: a) the electrodes dimensions, the position of the high-voltage electrode, the electrodes material, and distance between electrodes, the electrodes material and where necessary, the coating material type and design; b) the type of electric field (DC, AC, pulsed DC), appropriate to the highest degree of process efficiency.

The process time in all tests was limited to two hours. The process efficiency was measured by water cut volume % (residual water content in the emulsion). Stainless steel was chosen as suitable for the electrodes material. Especially when working with high salinity content (35 g/l NaCl), coating material (PVC, HALAR ECTFE) was found as a good alternative in avoiding short-circuits between the electrodes, and thus having a better control of the applied electric field strength. The inter electrode gap, related to the electrodes design, was tested (varied from 1 to 10 cm) according to the aimed electric field strength and type of electric field. Three different types of electric field were applied: direct current (0 – 35 kV), alternative current (125 – 375 kHz), pulsed direct current (0 – 35 kV, mHz).

Results:
All three designed electro coalescing units were tested with diverse emulsion qualities. Three different crude oils was used. In order to characterize them, relevant physical characteristics, such as density, viscosity and chemical characteristics, such as asphaltenes content (colloidal particles present in the crude oil considered as main contributor to emulsion stability) were determined. Similar characteristics for the three crude oils resulted: an average viscosity of 4 mPa*s (at 20°C) and an average density of 800 kg/m3(at 20°C) and an average low content of asphaltenes (around 1 wt. %). Significant differences were notified when determining the water-crude oil emulsion stability, measured by water cut volume % / time. Therefore, water cut volume % becomes a key parameter both for the process fluid quality and for the assessment of operation efficiency. Tests were done with emulsions: a) containing various volume ratios of 10 – 90 % for both water and crude oil, b) being prepared by different mechanisms: stirrer and ultrasound (which offer a wide droplet size distribution), c) with various salinity (related to 1, 10 and 35 g/l NaCl). The best performance was obtained when using the cylindrical reactor with electrodes in concentric position together with alternative current, in which case process efficiencies for diverse qualities of emulsions of 70 -100% was obtained. It couples the alternative current (160 - 200 kV/m, 40 – 73 kHz) and makes use of dielectrophoresis and dipole coalescence, employing an inhomogeneous electric field. From the experimental work, it was shown that it operated efficiently for the emulsions prepared by stirrer (30 µm average droplet size) and with water content from 30 – 40 vol. %) with an efficiency degree of 86%. For the emulsions with water content lower than 20 vol. %, and for the emulsions prepared by ultrasound procedure it has been registered a lower efficiency, less than 50%. These results were expected due to the calculations performed. According to calculations, emulsions with high water content are successfully separated. Besides, Fraunhofer IGB findings upon geometry and structural material influence on the electric field distribution, electro coalescent respectively were proved through the simulations performed.

‘Prepare for Integration of Separation Unit into Analysis Chamber’

Results:
For the Task 2.3 Prepare for Integration of Separation Unit into Analysis Chamber, discussions in this regard were held together with TI and the other partners in order to bring together all the technical specifications and to build the best appropriate testing unit. Technical aspects such as test loop concept, suitable ways of integration of electro coalescing unit into analysis chamber, requirements of the structural materials for analysis chamber, electrode connections, and sensors integrations were thoroughly discussed through E-mails, Skype Meetings and workshop.


‘Level Measurement’

RGU procured and tested two different types of sensors after a detailed technical review of available sensors in the market. These sensors, Rosemount 5000 GWR and Rosemount 5300 non-contacting radar, were procured from Emerson Process Engineering Limited. The overall purpose of the testing programs was to evaluate the two sensors with a view to determining the one that would be more appropriate for use in the project.

Stage 1:
1: Investigation of the effects of salinity on level measurement using brine solution of different concentrations.
2: Effect of predefined height on the accuracy of interface measurements.
3: Investigation of the possible application of echo curve and interface level to estimate emulsion level.
4: Effect of dielectric constant value of oil on the accuracy of interface level.

Stage 2:
5: Effect of predefined height and emulsion on the accuracy of interface measurement.
6: Interface measurement in the absence of emulsion and effect of dielectric constant.
7: Effect of changes in changes in water salinity on level measurement using the GWR.

Stage 3:
6: Effect of salinity on interface measurement using the GWR.
7: Oil level measurement using the GWR.
8: Level measurement using the non-contacting radar instrument.
9: A case study on changes in dielectric constant in a well stream of a typical North Sea production process.

Results:

Stage1:
• The level measurements with the GWR sensor were generally accurate with very little step changes in level. At this stage it was somewhat unclear if these changes could be attributed to salinity effect.
• The relative height of the oil and water phase could affect the accuracy of the GWR sensor. It was noted at this stage that the configuration where oil /water height ratio was 1:3 produced most accurate results. It was also noted that this finding was not conclusive at this stage.
• The level of emulsion formed by the physical interaction between the oil and water phase can be roughly calculated using the echo curve and measured interface level.
• It appeared the accuracy of the interface level was strongly dependent on the oil level (thickness) which was used in estimating the dielectric constant of the oil.

Stage 2:
• The measured level and interface could be accurately measured irrespective of percentage of water content (25% to 75%).
• There was a slight variation in dielectric constant of oil that produced these satisfactory results.
• The presence of emulsion layer did not prevent the GWR from functioning.
• Absence of emulsion would give a clear interface signal at any time.
• The accurate value of dielectric constants of the upper product must be known for accurate volume measurements.
• The level decreases as the salinity increases.
• The signal strength increases as the brine concentration.

Stage 3:
• Measured oil and water levels were reasonably accurate irrespective of the water salinity.
• Generally, the GWR was accurate for level measurement; however, knowledge of the fluid phase(s) was essential for calibration purposes.
• The non-contacting radar was unsuitable for the salinity scan project.
• Knowledge of the changes in dielectric constant of the particular fluid with process condition was essential for the calibration of the GWR sensor.
• The effect of pressure changes on the dielectric constant of a gas was more significant than the effect of changes in temperature.

Conclusion:
• Knowledge of the changes of dielectric constant of a fluid with changes in process temperature and pressure was essential for the calibration of the GWR sensor.
• The effect of pressure changes on the dielectric constant of a gas was more significant than effect of changes in temperature.
• There was a particular difficulty in knowing the precise value of the dielectric constant of fluids, however, it was believed that coalescence unit of the salinity scan could be the key to obtaining this information through the tracking of the echo curve analyser of the GWR sensor.



Development of control system

Activity/Results:
The SalinityScan Control System was built with industry standard components following normal rules for electrical systems of this kind. The system was built as a prototype but the design is well suited for series production. Adequate documentation was made to accommodate series production. The PLS, IO cards etc is made by Saia Burgess, a well-established Swiss manufacturer of programmable logic systems.

It was important to include safety switches and logic for decreasing risk for human injury from electricity, temperature and substances under high pressure. The system includes an advanced data logging system that is particularly useful in research projects to collect data and gain experience with the process. The system has gone through Module Test at TI’s facilities in Oslo and it has been tested “on-site” as a part of the complete SalinityScan process in suitable facilities at TI’s Gas Centre facilities at Haugesund. The tests completed successfully.

Design of analysis Chamber

The work with the design of the analysis chamber started in the second period, but the main steps in the work were presented for the consortium at the 9 Month meeting.

The design process followed these main steps:
• Establish task plan
• Review/update specifications
• Concept design/integration with coalescer and sensors
• Construction/dimensioning/analysis
• Production drawings for prototype
• Manufacturing
• Inspection
• Testing

The mechanical and automation teams at TI worked together with Fraunhofer to secure proper integration. The design of the analysis chamber affects both the coalesce and the sensor designs.

All steps were carried out with collaboration of the SMEs. The final production drawings prior to the production was presented to the consortium and approved. An external testing facility performed the necessary pressure tests of the chamber after production for approval.

Results:
All necessary components were included in the prototype:
• Analysis chamber (inner volume)
• The coalesce unit inside (developed by IGB in collaboration with TI)
• Inlet and outlet valves
• Salinity sensors (pH)
• Level sensor (GWR, tested and approved by RGU)
• Temperature sensors


Design and Construction of Test Setup

The project had a thorough evaluation of where the test setup of the project should be located. Several alternatives were visited and the most promising were to set it up at the RTD partner RGU’s facilities in Aberdeen or at TI’s Gas centre facilities in Haugesund. It was decided by the industrial partners that they wanted to use the facilities at TI Haugesund.

In June 2012 the first meeting was held at TI Haugesund to establish task groups and responsibilities. The Version 1 task plan was established. Version 1 P&ID proposal was drafted by TI and the version 1 was reviewed in a phone meeting in September 2012. The P&ID was reviewed further according with input from partners and the outcome was the second and final version.

The test-loop was realized as a joint effort between Tool-Tech and TI. After the second P&Id was done, TI Gas center was in charge of specifying the production and get the quotations for building the test setup inside a 20 feet container.

The production was followed up closely and pressure, leakage, and functionality tests were performed.

Results:
A fully functional test setup was ready for integration in March 2013. Progress was delayed due to an extremely and unusual cold winter. Frost would have been a danger to the test with water because of the possibilities of frost expansion in the pipes during testing.

The test system contains all the necessary features to run tests on the analysis chamber. The system enables filling of the analysis chamber, controlled emptying and cleaning with realistic chemicals like MEG and methanol.

The test system has a higher pressure specification (100 bar) than the analysis chamber (40 bar) and can therefore be used on a possible upgraded analysis chamber.

Integration

Activity:
The integration was divided in two main sections in the project.
1. The integration of the coalescent function was integrated with the analysis chamber. This process started already at the start of the development of the analysis chamber. The integration has been a co-development between TI and Fraunhofer. A plan and sketches of the analysis chamber was worked out together. The basis for the chamber was set and the link for integration determined. The specifications from IGB were included in the analysis chamber development. Final technical drawings were approved by the whole consortium.
2. The second integration was the total test system assembly. The test loop was built in Haugesund under surveillance and specified by TI Gas centre.

After the test loop was ready the automation and electronics was integrated. The PLS was built at TI in Oslo and moved to Haugesund for integration. The system was fully integrated when the analysis chamber was produced and delivered. Adjustments and preparations were done for the system to be finalized.

Results:
The final result of the integration was the complete and fully functioning test system.

The system was ready for testing with the following integrated features:

• Pressure approved analysis chamber with coalescent features closely integrated in the design.
• A power generator connected to the coalescent unit able of adjusting to desired inputs for a large variety of test settings
• All sensors integrated in the analysis chamber
• Level sensor for measuring multiphase levels after separation and functioning as a grounded electrode in the coalescent unit
• pH sensors for measuring the salinity in the water phase after separation
• Temperature sensors for monitor the temperature development during analysis and possibly detecting pressure changes
• Additional pressure sensors are placed in the test loop surrounding the analysis chamber
• The level sensor is connected to its one program for monitoring the level post treatment
• A complete test loop with piping, reservoirs, valves and pumps all connected to the PLS
• The complete system is fitted in a 20 feet shipping container


Testing

Several preliminary tests were performed to make sure that the prototype and the test loop functioned properly and safely:

• Initial pressure test of analysis chamber after production
• Dry test of test loop components
• Water pressure test of the test loop
• Water test loop test to check all test cycles functioning
• PLS booting and function test
• Testing and calibration of sensors

The testing of the test loop led to several minor adjustments and changes. After these adjustments the system was approved and ready for next step.

Testing of the system fully integrated
• Filling of the chamber with crude oil
• Test of mixing fluids inside the test loop
• Running of all test loops with integrated analysis chamber
• First testing of separation of fluid with the electro coalescent

Results:
The preliminary testing results:
• Analysis chamber approved up to 40 bar post production. It is dimensioned to 100 bar but due to the level sensor flange connection only approved to 40 bars by the supplier, higher pressure approval was unnecessary. If in a later stage post project it is desired to have a higher pressure new testing must be done, although the chamber is theoretically tested to 100 bar by a finite element analysis
• All components were dry tested post production with minor errors corrected
• The test loop was pressurized before connecting the analysis chamber. The leaks and pressure valve errors were corrected
• A manual test of the different test loops were performed with success
• The PLS was integrated with the system successfully after a thorough work adjusting and fitting the systems together. Changes in the PLS program were and can be done online form anywhere
• Testing and calibration of the sensors were performed without any major problems

Full scale testing:

Activity and results
The first test was run with 20 liters of crude oil and 3 liters of salt water. The results showed some separation of the fluids. However most of the separation was still in the emulsion phase. The conclusion from the first test is that the time used was not completely and the test period should have been extended for a better result. The power input was probably also too low. And this needed to be investigated further.

The second test was run with 16 liters of crude oil and 7 liters of salt water. The test ran for 4 hours. The level sensor indicates a 10 mm height of salt water and rest is oil on top. The analysis chamber was emptied after test for control measurement. The fluid phases were at 350 ml of salt water, 600 ml of emulsion and 2400 ml of oil.

As the results was not fully satisfactory there is a need for adjustments to sensors and power supply. It appeared that the frequency settings should have been adjusted on the power generator and that an adjustment to frequency would have fixed the problem with too low power output. Regarding the level sensor this is controlled with a high voltage relay. The purpose of the sensor is both giving a high voltage output and performing level measurements. It appeared that the switching in the relay was a problem and that this problem may be solved by checking the SW controlling the sensor. This will be verified in new tests and should be relativity easy to fix.

The test system ran with fully integrated components and functioning control system. The conclusions from the test are that the complete test loop itself worked satisfactory. However sensors/relay and power/frequency problems must be corrected and adjusted for a fully successful validation. There are no indications that there are any particular problems with the sensor in itself or the coalescent unit and its functioning. The test has shown where the problems are. They has been isolated and can be investigated individually. A solution should be expected to be found with relatively little effort. Even with the problems encountered in the tests we maintain that the overall solution, design and functioning of the test rig is successful. Further test must be done post project as the tests ran all to the end of the project period and no more test were possible within the project period.

With respect to the separation unit this has been successfully tested separately and there is no reason to believe that it should not perform satisfactory also in the integrated unit.

SEE ALSO the attachment provided by Fraunhofer IGB on how to fix the control of the separation unit. This is further described in Deliverable 5.2 as well.
Related deliverable: D5.2 Test report

Potential Impact:
With some more testing and validation of the test rig the results of the SalinityScan project will give the SMEs in the project an opportunity to produce and market a product which does not exist in the current subsea instrumentation industry. This is planned to be done and funding for further validations are available. Combining the output data from the SalinityScan instrument with existing MPFMs opens up a new world of benefits and possibilities for the industry. The uniqueness of the system brings about great commercial opportunities. The SalinityScan system allows petroleum engineers to regularly update the calibration parameters of MPFMs to adjust for variations in salinity, thus reducing measurement errors significantly. The development of the SalinityScan system will consequently aid in improving well management and increasing the recovery factor of subsea oil wells. Due to very high subsea production, these two effects undoubtedly have a significant economic impact. The need for salinity monitoring derives from the fact that most MPFMs use measurement principles that are affected by the level of salinity differing from that of the reference fluid used in initial calibration of the system. The variation incurs a measurement error that may significantly offset the volume fraction measurements of the oil, water and gas, with the production implications and economic loss this brings. To provide an example of the economic loss, consider a typical subsea well in the North Sea. It produces 3782 barrels/well/day, which, given an oil price of €47 per barrel results in a well per hour production value of €7406. Given a 2% error in the oil fraction measurement, this may lead to a loss of €148 per hour per well. Accumulated over a year this signifies a considerable loss, €1.296 million. The savings incurred by fixing measurement errors are substantial, but adding to this is the potential increased profits related to increased life of wells achieved by the improved well management, possible through semi-continuous salinity measurement. Early detection of water breakthrough enables early intermittent or permanent shutdown of wells that start producing large amounts of water. These further increases the potential savings made possible by the SalinityScan system.

Benefits by combining SalinityScan with a MPFM unit;
• Improves confidence in flow meter readings
• Provides reference data for calibration of Multi-Phase Flow meters and monitoring of changes in reservoir conditions.
• Increases revenues through correct data from flow meter
• Improves life-of-field reservoir management
• Improved diagnostic abilities, at a lower cost
• Reduces use of chemicals to prevent scaling through measurement of salinity and pH of produced water.
• Increases information flow from subsea well sensors. Reference data to compare with continuous flow monitoring.
• Retrofitting: Can be retrofitted on existing subsea systems and flow meters
• New-built: Can be combined with Multiphase flow meter of choice in new installations
• The system can be combined with a multiphase meter and provide added functionality that enables update of flow meter calibration set-up with changes in produced water salinity.
• The instrumentation technology used in the reference system is relatively simple and will provide accurate data at moderate system cost.
• With the on-line sampling and analysis system, it will not be necessary to take samples with intervention vessel and send to laboratory – This represents a huge saving.
• Online system – Sampling and analysis available at all times.
• Verification of liquid fractions in multi-phase flow for comparison with multiphase meter readings.

The International Energy Agency (IEA) estimates that approximately 64 million barrels a day (b/d) in added capacity is needed to fill the demand for oil in 2030. A considerable part of this demand will be covered by subsea wells. The number of subsea oil and gas wells is increasing, and the growth is estimated to reach 1000 per year in 2014. Important emerging deepwater markets are in Brazil, Gulf of Mexico and the Barents Sea, of which Brazil is the largest, by
far. Petrobras alone are reported to have a shopping list of 3930 X-mas trees (one per subsea well) from 2008-2015 (that is 500 a year, or 50% of the market). There is a significant trend that subsea wells are more heavily instrumented, promising a considerable increase in market for multiphase flow meters (MPFM).

Markets
The primary market for the SalinityScan system is retrofitting existing installations where multiphase flow meters are employed with this novel measurement sample and analysis unit. Since the unit has the basic functionality of a choke valve when not in measurement mode, the concept idea is to bypass the existing choke valves on subsea manifolds with the sampling system. Effort has been put into enabling easy adaptation to most existing choke valves. This replacement may be performed during routine replacement or maintenance operations on the subsea installations, thus decreasing the installation costs.

A secondary market will be targeting new subsea oil and gas field developments in which multiphase flow meters are installed. It is estimated that this market will grow rapidly and the market potential is considerable. A possible market share in the subsea market for this invention depends on the future development and implementation of multiphase flow monitoring in those markets.

Final commercialization
Based on the feedback from potential clients and market as a whole, a commercial strategy will be developed.

Pilot installation topside for an oil company is seen as a next step before a pilot installation subsea is possible. The plan is to approach Statoil when the concept has been further developed and verified through testing. Statoil is a major oil and gas producer and the biggest operator in Norway.

The consortium will have meetings at 6-12 months intervals to make sure the plan is followed post project.

Patenting
The original idea to Salinityscan is patented by ToolTech. However the Salinityscan project has come up with several new inventions that modify the original idea. Supplements or a new patent will therefore be filed. Until this is done the project is very careful in not revealing too much of its innovations.

Further funding
The project partners have got funding from the Fondation Franco-Norvégienne (FNS) over 3 years in total NOK 2.4 mill. This is a very good start for the post project work. The funding will be used to bring the technology to the next step i.e. a topside installation in cooperation with an oil and gas producer, most likely Statoil.


Dissemination activities

The project and in particular the owners of the foreground, the SMEs have been very restrictive and careful about not revealing the Salinityscan technology before it has reached a mature level and is functioning properly. The restrictive approach has been a core idea from the start of the project. The value of the results is in a validated technology that can be presented to the customers. The technology must also be protected before it can be disseminated.

An approach where the technology is not validated and presented to customers has been view as a very big risk for failing in the market as the whole concept may be turned down by potential buyers. This again may lead to problems in getting a second opportunity and that the ideas of the project may be copied by the customers piece by piece. Any advantage of being first in the market may also be lost. The partners are also dependent of further funding or co-funding by a third party for getting the Salinityscan technology set into production. Starting cooperation too early with a customer is not wanted as the value of the project may be set too low and the commercial upside for the SMEs may be lost or minimal.

Unfortunately the project did not manage to fully validate the technology within the project time and with the resources available. It is a strong belief among the partners that the project is a success, even if some validations are still needed. In this situation the dissemination activities have been further postponed. This in line with the project partners strategy but has led to a situation where the dissemination activates have been limited concerning the concrete promotion of the Salinityscan results.

On the general level the partners have been active in the market monitoring competing solutions, attending seminars and exhibitions as well as having dialogs with major players about current technology status in the field.

The partners Tooltech and SubC are two companies that have their full businesses connected to the oil and gas industry. The have therefore an excellent overview of what is going on in the market and what are the needs of the major players that may be the customers of the Salinityscan system. They therefore also communicate regularly with their potential customers and know the market situation very well. A leaflet has been produced and will be used at exhibitions and in communication with potential customers.

When the innovations are protected, the new scientific knowledge created by the project will be actively disseminated amongst academic communities to validate it. Hence, the full range of scientific, technological and product/process/system specific dissemination activities can be enabled without compromising the protection of the foreground IPR.

The Consortium Agreement covers the dissemination and exploitation of all the project results to companies outside of the consortium. If needed the CA will be further updated. The agreement will cover the collaboration between the partners to facilitate exploiting of the foreground. This will encompass agreements in respect to the patent application made, and go on to detail the terms and conditions under which licensing of the technology will take place. This licensing to third parties is seen as critical to the rapid roll out of the technology across the EU and beyond, speeding the proliferation of the technology and penetration of markets sectorally or geographically distant from the partners.

List of Websites:
http://www.salinityscan.com

Documentos relacionados

• final1-leaflet-salinityscan.pdf