CryoMet
Metrology for reliable liquefied energy gases measurement
The project has received funding from the European Partnership on Metrology, co-financed by European Union Horizon Europe Research and Innovation Programme and from the Participating States.
Work Packages
The aim of this work package is to determine the measurement reliability and uncertainty of (bio-)LNG flow meters in-field, including 2-phase flow, meter insulation type, reproducibility, and temperature cycles. In addition, to develop traceable (bio-)LNG and LH2 meter diagnostics and to demonstrate, using reference data sets, a target accuracy of 0.5 % for (bio-)LNG flow meters.
WP1 will establish a data set of LNG flow meter calibrations in the SI-traceable LNG facility in the port of Rotterdam (The Netherlands) developed in ENG03 LNG, ENG60 LNG II, and 16ENG09 LNG III. This traceable (to primary level) LNG and liquefied nitrogen flow calibration standard has a 0.17 % (k = 2) uncertainty claim on mass flow.
The calibrations and tests will be performed at a maximum pressure of 1 MPa and a maximum volume flow rate of 165 m3/h (about 75000 kg/h). A systematic investigation into in-field industry LNG flow process variables will be carried out in Task 1.1 and a suitable metering line with LNG flow meters will be designed and built.
The data set from Task 1.1 will then be expanded in Task 1.2 where the uncertainty from LNG terminal installation effects will be determined using a cryogenic LDV (CryoLDV, also known as “RDCL” in French) LNG flow standard (maximum flow rate at 400 m3/h, about 180000 kg/h), which was developed in ENG03 LNG, ENG60 LNG II, and 16ENG09 LNG III.
In Task 1.3, the reference data set will be combined with CFM numerical modelling to extend the range of industrial process condition uncertainty estimation, including extrapolation to LH2 temperatures (-253 °C / 20 K).
Leader: DTU
The aim of this work package is to determine the reliability of (bio-)LNG composition measurements under in-field conditions, including sampling errors, and the achievable accuracy of LNG composition measurement equipment. Then to demonstrate, using reference data sets, a target uncertainty of less than 0.3 % (k = 2) for the online determination of LNG density.
In (large-scale) custody transfer of (bio-)LNG, it is common practice to determine the quantity transferred on a calorific-content basis. Therefore, knowledge of (bio-)LNG composition is essential to calculate properties such as density and heat value. Those properties are required, together with other parameters, to calculate the amount of energy delivered for custody transfer purposes. In Task 2.1 publicly available reference data sets of (bio-)LNG composition measurements will be collected, and new data sets produced where needed, in order to collect input for the uncertainty evaluation of composition measurements and physical properties of (bio-)LNG. (Bio-)LNG composition can be measured directly in the liquid phase or after vaporisation.
When the composition is determined by vaporisation and subsequent gas analysis, sampling is the most critical point of the (bio-)LNG measurement chain as the fluid must be conditioned from its initial state (liquid at low temperature) to a final state (gas at ambient temperature). Analysis onsite with GCs provides results at intervals of minutes and requires calibration at regular intervals. The uncertainty associated with such sampling will be evaluated in Task 2.2. There are several indirect methods to calculate (bio-)LNG density, such as the revised Klosek-McKinley method, and the GERG wide-range EoS method (GERG-2008). The (bio-)LNG density can also be measured directly e.g. using a Coriolis mass flow meter. The aim of Tasks 2.3 and 2.4 is to demonstrate a target uncertainty of less than 0.3 % (k = 2) for the determination of (bio-)LNG density, using indirect and direct methods (respectively).
The aim of this work package is to determine the accuracy of (bio-)LNG in-field temperature measurements, including the impact of static and dynamic effects on the temperature measurement system. Then to demonstrate, using SI-traceable reference data sets, a target uncertainty up to 0.5 °C (k = 2), for in-field conditions and for cryogenic temperatures down to -253 °C (LH2).
Task 3.1 aims to measure and simulate the static and dynamic errors of a representative sensor used in the VSL LNG facility. The behaviour of the sensor immersed in different liquefied gases will be modelled. Task 3.2 aims to produce methods for traceable calibration of the temperature sensors used to measure liquefied gases (LH2 and (bio-)LNG). In addition, to evaluate the extrapolation uncertainty (target uncertainty up to 0.5 °C, (k = 2) at -253 °C (20 K) for sensors calibrated in the temperature range from 0 °C (273 K) to -196 °C (77 K). This is in order to reduce the calibration temperature range using extrapolation methods that extend the usable range of the sensors to lower temperatures. In Task 3.3 a comprehensive uncertainty budget will be created for a representative sensor used in the VSL LNG facility (i.e. a typical sensor used for temperature measurements of liquefied energy gases under in-field process conditions) with a target uncertainty ≤ 0.5 °C, (k = 2).
The aims of this work package are:
- to perform SI-traceable flow and temperature measurements in LH2 conditions and to develop SI-traceable calibration procedures for LH2 flow, isomer composition, and temperature measurement systems.
- to verify the performance of the developed (bio-)LNG and LH2 metrological infrastructure developed, comprised of calibration procedures and existing LH2 calibration standards, including through inter-comparisons of the SI-traceable calibration systems.
In Task 4.1, the methods and results from WP1, WP2 and WP3 will be progressed into SI-traceable calibration procedures for liquefied gas flow, density, and temperature measurements. Task 4.2 is dedicated to the determination of LH2-composition, i.e., the hydrogen isomer composition (para- and ortho-hydrogen), and its uncertainty because there is a clear knowledge gap in science and, therefore, also in the industry. Obtaining SI-traceability for LH2-composition determination will also be tackled.
The second aim will be achieved in Task 4.3 by performing and analysing inter-comparison data obtained from existing SI-traceable liquefied gas calibration standards from WP2, WP3, and Tasks 4.2 and 4.3.