WO2019132657A1 - Sampling device and method for sampling a cryogenic fluid for measuring at least one property - Google Patents

Abstract

The invention provides a sampling device for sampling a cryogenic fluid for measuring at least one property, said sampling device comprising: - a cold section comprising a sample probe extending into said cryogenic fluid for retrieving a quantity of said cryogenic fluid, said sample probe fluidly coupled to a flow control section, said flow control section comprising a cold fluid line for transferring said quantity of said cryogenic fluid to an outlet end of said fluid control section, said cold fluid line allowing splitting off a part of said quantity of said cryogenic fluid, leaving a sample, and vaporization said part of said quantity of said cryogenic fluid for cooling said sample and thus preventing boiling of said remaining sample in said cold fluid line; - a heating section, fluidly coupled to said cold fluid line of said cold section for receiving said sample and comprising a heating device for bringing said sample in a gaseous phase at an outlet end, and said outlet end fluidly coupled to a measuring device for measuring said at least one property of said sample in said gaseous phase.

Description

SAMPLING DEVICE AND METHOD FOR SAMPLING A CRYOGENIC FLUID FOR

MEASURING AT LEAST ONE PROPERTY

5 Field of the invention

The invention relates to a sampling device for sampling a cryogenic fluid, and a method for sampling a cryogenic fluid.

Background of the invention

0 A cryogenic fluid, like for instance liquid natural gas (LNG), is extracted from a process by means of a sampling device. Such a sampling device is provided for taking a representative sample of the fluid. In particular, sampling often take place in a transfer line. The sample is then to be transferred to a measuring device for determining for instance the composition of the sample or its physical properties.

5 Taking or collecting a representative sample can in many processes be challenging, but this certainly is the case in cryogenic fluids, and more in particular if such sampling is to take place in-line and continuously or with relatively small time intervals.

In the art, many devices and methods have been proposed.

0 US9097695 to SGS North America, Inc., in its abstract states“Composite sampling of a fluid flowing through a conduit includes collecting, in a vessel coupled to the conduit through which the fluid is flowing, a first discrete sample of fluid from the conduit, the first discrete sample having a first selected volume, and collecting, in the vessel and at a first interval from the first sample, a second discrete sample of the fluid5 from the conduit, the second discrete sample having a second selected volume, thereby forming a composite sample in the vessel while the vessel is coupled to conduit. The composite sample includes the first discrete sample and the second discrete sample, and may include one or more additional discrete samples.; An apparatus for collecting the composite sample includes a gas chromatograph, and is arranged such that the composite0 sample is provided to the gas chromatograph without removing the composite sample from the apparatus or transporting the composite sample.”

US8210058 to Welker, Inc., in its abstract states“A sampling cylinder for LNG (liquefied natural gas) is provided. The sampling cylinder includes a piston cylinder arrangement having opposite end members closing the chamber inside the cylinder. Various porting arrangements are provided for allowing fluid to be fed into a chamber inside the cylinder on opposite sides of a piston. A sample chamber is provided at one end member of the cylinder. The end member containing the sample chamber is also provided with a heat exchanger that may be connected to a source of coolant and preferably the LNG to be sampled to effect cooling of the end member at least partially prior to the sample chamber having a sample of LNG injected thereinto.”

W02006/002030 to Mustang Engineering, L.P., in its abstract states“Method and apparatus for vaporizing cryogenic fluids in which an intermediate heat transfer fluid is first heated across a heat transfer surface with ambient air, and then the heat transfer surface provides heat to vaporize the cryogenic fluid.”

US9285299 to Mustang Sampling LLC, in its abstract states“System and method for natural gas liquid sample pressure regulating vaporizer system including a vented cabinet having a gas sample input, a pressure regulator, a single path vaporizer, a liquid block, a heated regulator and a gas sample outlet, and a communications assembly including a temperature controller, a communication outlet, and a power input electrically connected via appropriate secure feedthroughs to the cabinet.”

US9459185 to Mustang Sampling, LLC, in its abstract states:“Provided herein is a solar powered system for a gas sampling and analysis for placement and operation remote from conventional infra-structure that utilizes a minimum of power to obtain a sample extracted from a source such as a pipeline or well-head, conditions the extracted sample, transmits the conditioned sample through vacuum jacketed tubing to an analyzer while maintaining the sample at a temperature and pressure preventing phase transition, condensation or component partitioning.”

JPS57165737 of 1982 in its abstract states“PURPOSE: To make it possible to perform sampling without discharging a specimen to the outside of a system, by providing a cooling line and the like which is arranged on the path from a drum through a pump and a liquid extracting device to said drum, to the storing drum of the liquid mixture. CONSTITUTION: The sampling device is provided with the storing drum 5 of the liquid mixture, the cooling line which is arranged on the path from said drum through the pump 6 and the liquid extracting device 1 to said drum, a sampling line which is arranged on the path from said liquid extracting device through a valve 12 and a vaporizer 2 to said drum, and a side pipe (f) having a sampling nozzle 4 and a valve 13 at the downstream from the vaporizer on said sampling line. The part of the component of the specimen has a very low boiling point and its entire components are evaporated by heating. Therefore said device can sample the specimen very easily and highly accurately, without discharging the specimen to the outside of the system.”

A disadvantage of the prior art is that often a sample is not representative of the material to be measured, taking a sample takes much time, required a large volume of material. It was found that partial evaporation of the sample causes problems. The devices that are proposed in many examples are complex or require complex handling.

Summary of the invention

Hence, it is an aspect of the invention to provide an alternative sampling device, which in various embodiments preferably further at least partly obviates one or more of above-described drawbacks.

There is currently provided a sampling device for sampling a cryogenic fluid for measuring at least one property, said sampling device comprising:

- a cold section comprising a sample probe extending into said cryogenic fluid for retrieving a quantity of said cryogenic fluid, said sample probe fluidly coupled to a flow control section, said flow control section comprising a cold fluid line for transferring said quantity of said cryogenic fluid to an outlet end of said fluid control section, said cold fluid line allowing splitting off a part of said quantity of said cryogenic fluid, leaving a sample, and vaporization said part of said quantity of said cryogenic fluid for cooling said sample and thus preventing boiling of said remaining sample in said cold fluid line;

- a heating section, fluidly coupled to said cold fluid line of said cold section for receiving said sample and comprising a heating device for bringing said sample in a gaseous phase at an outlet end, and said outlet end fluidly coupled to a measuring device for measuring said at least one property of said sample in said gaseous phase.

The invention further pertains to method for measuring a property of a flow of cryogenic fluid, comprising:

- providing a sample probe into said flow of cryogenic fluid for retrieving a quantity flow of flow of cryogenic fluid and which is representative of said flow of cryogenic fluid;

- transferring said quantity flow to a flow control section; - vaporizing a part of said quantity flow, with a remaining flow forming a sample flow, said vaporizing cooling said sample flow for preventing boiling of said sample flow.

It was found that a part of the problems in the prior art was due to partial evaporation. The current sampling device provides fast sampling. In embodiments, it was found that the sampled material was representative of the material. Using part of the material and allowing it to evaporate (vaporize or expand) in a controlled manner in order to cool further sample provides a more representative sample.

In an embodiment, the fluid line comprises a flow control branching line for said splitting off a part of said quantity of said cryogenic fluid, said flow control branching line comprising a vaporizing end for vaporizing at least part of said part of said quantity of said cryogenic fluid for cooling said sample downstream of said flow control branching line. For example, the flow control branching line comprises one or more nozzles. In fact, the fluid line may comprises more than one branching lines or at least one branch. In an embodiment, the or a vaporizing provision provides the cooling vapor to cool the remaining sample. In an embodiment, a chamber or enclosure is provided surrounding at least part of the fluid line. The vapor provision provides the vapor in the chamber or enclosure, thus cooling the remaining sample.

The current sampling device can be used for cryogenic fluids, but may also be used for other fluids that need to be sampled close to their critical stage. Using phase changing of part of the fluid for preventing boiling of the remaining sampled fluid proved an effective measure.

Furthermore, in a further embodiment the design of the sample probe allows retrieving a representative sample from a flow of fluid.

In an embodiment, the sampling device further comprises a thermal expansion section having an inlet end fluidly coupled to an outlet end of said flow control section and an outlet end fluidly coupled to an inlet end of said heating section, said thermal expansion section comprising an insulation coupling coupled to said flow control section and said heating section, and a flexible fluid line fluidly coupling said thermal expansion inlet and outlet and running inside said insulation coupling and comprising at least one bend for absorbing expansion and shrinkage between the flow control section and the heating section.

In an embodiment, the sample probe comprises an inlet end and an outlet end, said inlet end comprising a fluid inlet and a fluid outlet which open in functionally opposite directions, a fast loop channel connecting said fluid inlet and said fluid outlet, and a sampling channel for retrieving said quantity of cryogenic fluid from said fast loop channel, said sampling channel comprising a sampling channel outlet at or near said sample probe outlet end. This, the probe uses a difference in dynamic pressure for sampling.

In an embodiment, the sampling channel has a smaller cross sections area than a cross sectional area of said fast loop channel. In an embodiment, the sampling channel has a cross sectional area which is 0.2-0.5 times said cross sectional area of said fast loop channel. In an embodiment, the ratio is 0.25-0.35 times.

In an embodiment, the sample probe has an elongated shape having a longitudinal axis, wherein said fast loop channel comprises a first branch, a U turn and a second branch, said sampling channel at one end fluidly coupled to said U-turn.

In an embodiment, the sample probe comprises a sample loop for said fluid, said one end of said sample loop comprising a first opening and an opposite end of said sample loop comprising a second opening, wherein said first and second opening are in line.

In an embodiment, the flow control section comprises a metal core comprising a fluid channel providing said flow control section fluid line, a branching line provided with a restriction at or near its end and a container providing an evaporation space around said metal core, in particular said restriction provided at said inlet of said flow control section and inside said container.

In an embodiment, the thermal expansion section comprises a fluid line having a length which is longer than a direct line connecting said flow section outlet and said heater section inlet, in particular said fluid line has at least one bend, in particular has an S-shaped for in operation absorbing and eliminating forces and material tension due to large temperature differences, in particular said fluid line has a cross sectional area which is between 0.1 and 0.01 times smaller than a cross sectional area of said flow control section fluid line.

In an embodiment, the heating section is adapted for flash vaporizing said fluid sample, wherein heater section fluid line provides a cross section increase of between 10-100 times, in particular said heater section fluid line is coiled and is adapted for providing a zero dead volume accumulator. In an embodiment, the heater section in operation is filled with a thermal oil and comprises an immersion heater for heating.

In an embodiment, the heater section fluid line comprises a staggered static mixers for distributing heat of said thermal oil to said incoming and vaporized fluid, for mixing said vaporized fluid into a homogeneous gas sample.

The terms“upstream” and“downstream” relate to an arrangement of items or features relative to the flow of fluid, flowing from“upstream” to“downstream”. In the current device, sampled fluid flows and is transported from a source of fluid, and passes through various sections to a measuring device. During transportation, the sampled fluid sample should be and remain representative of the fluid sampled. The sampled fluid thus flows from upstream at the fluid source downstream to a measuring device that measured a property of the fluid.

The term“substantially” herein, such as in“substantially all emission” or in “substantially consists”, will be understood by the person skilled in the art. The term “substantially” may also include embodiments with“entirely”,“completely”,“all”, etc. Hence, in embodiments the adjective substantially may also be removed. Where applicable, the term“substantially” may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. The term“comprise” includes also embodiments wherein the term“comprises” means“consists of’.

The term "functionally" will be understood by, and be clear to, a person skilled in the art. The term“substantially” as well as“functionally” may also include embodiments with “entirely”, “completely”, “all”, etc. Hence, in embodiments the adjective functionally may also be removed. When used, for instance in“functionally parallel”, a skilled person will understand that the adjective“functionally” includes the term substantially as explained above. Functionally in particular is to be understood to include a configuration of features that allows these features to function as if the adjective “functionally” was not present. The term“functionally” is intended to cover variations in the feature to which it refers, and which variations are such that in the functional use of the feature, possibly in combination with other features it relates to in the invention, that combination of features is able to operate or function. For instance, if an antenna is functionally coupled or functionally connected to a communication device, received electromagnetic signals that are receives by the antenna can be used by the communication device. The word“functionally’' as for instance used in“functionally parallel” is used to cover exactly parallel, but also the embodiments that are covered by the word“substantially” explained above. For instance,“functionally parallel” relates to embodiments that in operation function as if the parts are for instance parallel. This covers embodiments for which it is clear to a skilled person that it operates within its intended field of use as if it were parallel.

Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

The devices or apparatus herein are amongst others described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation or devices in operation.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "to comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the device or apparatus claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

The invention further applies to an apparatus or device comprising one or more of the characterising features described in the description and/or shown in the attached drawings. The invention further pertains to a method or process comprising one or more of the characterising features described in the description and/or shown in the attached drawings. The various aspects discussed in this patent can be combined in order to provide additional advantages. Furthermore, some of the features can form the basis for one or more divisional applications.

Brief description of the drawings

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

Figure 1 schematically depicts an embodiment of the sampling device, indicating the cold section, and the heating section;

Figure 2 schematically shows a sample probe, and

Figure 3 schematically shows the sample probe in more detail.

The drawings are not necessarily on scale

Description of preferred embodiments

Figure 1 schematically depicts an sampling device 1 showing various sections. The schematic drawings shows the sampling device 1 coupled to a transfer line 2 as a source of fluid. The sampling device 1 comprises in the depicted embodiment a sample probe 3 extending into transfer line 2. Sample probe 3 is in the current embodiment at an outlet end fluidly coupled to a process insulation valve 4. Via this process insulation valve 4, the sample probe 3 can be de-coupled from the rest of the sampling device 1, allowing removal of large part of the sampling device 1, i.e. the part downstream of the valve 4, without disturbing the transfer line 2.

The process insulation valve 4 is fluidly coupled to a flow control section 5. The sampling device 1 further comprises a heating section 6 for heating and vaporizing a representative sample of the material in the transfer line 2. In the current embodiment depicted in figure 1, the flow control section 5 is fluidly coupled to the heater section 6 via a thermal expansion section 7. The thermal expansion section 7 in this embodiment comprises an insulation jacket 8 enclosing in the current embodiment a fluid line 9 which comprises a bend and which can absorb expansion and shrinkage between the flow control section 5 and the heater section 6 which occurs due to temperature differences between these sections. In an embodiment, the fluid line 9 has a cross sectional area which is smaller than the cross sectional area of the incoming line. This increases fluid flow velocity and increases the mechanical flexibility of the fluid line 9. Furthermore, as will be explained further on, some of the fluid that is captured by the sample probe will be evaporated in the flow control section. Thus, a reduction in cross sectional area further prevents boiling or other inhomogeneous effects. In an embodiment, the cross sectional area of fluid line 9 will be 0.5-0.01 times the cross sectional area of the flow control section fluid line 23. In an embodiment, the cross sectional area of fluid line 9 will be 0.2-0.02 times the cross sectional area of the flow control section fluid line 23. In the current embodiment, about 0.03 is selected.

Furthermore, the fluid line 9 comprises at least one bend. This allows some change in the distance between the flow control section 4 and the heater section 6 due to temperature changes and differences. It can also absorb other causes of mechanical stress. The length of the fluid line is this larger than a distance between the outlet of the flow control section 22 and the inlet of the heater 29.

Next, the sample is introduced into the heater section 6. Here, the sample which was up to then in a liquid phase is brought into a gaseous phase. The thermal expansion section 7 can in fact also provides an insulation between the flow control section 5 and the heater section 6. From the heater section 6, the sample that is now a gas flow advances to a measuring device. At this stage, volume increases at least 100 times. For LNG, for example, volume increase will be 600-700 times. Such a measuring device can in fact comprise any device measuring a property of a gas. An example is a gas chromatograph (GC) or a caloric value determining device (CVDD).

In an embodiment, the heater section 6 comprises an oil heater 10 with a conduit spiralling around it. A cross sectional area of the heater conduit fluid line 28 in an embodiment is between 10-100 times a cross sectional area of the fluid line of the thermal expansion section 7. In an embodiment, the cross sectional area of the heater section fluid line 28 is between 15-75 times a cross sectional area of the fluid line 9 of the thermal expansion section 7. In the current embodiment, about 64 times is selected. The heater section fluid line 28 provides a zero dead volume accumulator by means of an integrated static mixer.

In figure 2, in more detail a schematic drawing is shown, in which the process insulation valve 4 is shown with a sample probe attached to it. Here, the process insulation valve 4 is a ball valve of a type that is known as such. Connected to the process insulation valve 4 is a sample tap or process connection 1 1, that is fluidly coupled to the cryogenic fluid source. The cryogenic fluid can freely flow into the process connection 11. The process connection 1 1 may comprise a further insulation jacket surrounding it.

Inside the process connection 1 1, the sample probe 3 extends into the cryogenic fluid, here into the cryogenic transfer line 2. The sample probe 3 is fluidly coupled to the process insulation valve 4 which in turn is fluidly coupled to the flow control section 5. The cryogenic fluid in the process connection 1 1 keeps the sample probe 3 at cryogenic fluid temperature, preventing undesired boiling of cryogenic fluid in the sample probe 3. In figure 2, a flow direction F of the fluid has an arrow that points into two direction, to indicate that the probe in this embodiment works with both flow directions in the way it is drawn. The ball valve may comprise a restriction with respect to its usual flow-through area. The resulting channel or conduit 31 is indicated, fluidly coupled to the probe 3.

In figure 3, the sample probe 3 is discussed in more detail. Sample probe 3 is in particular suited for sampling in a flow of cryogenic fluid, or retrieve a sample from a flow of cryogenic fluid, as will be clear from the explanation below.

The sample probe 3 has an inlet end 12 and an outlet end 13. Outlet end 13 can be fluidly coupled to the process insulation valve 4 as indicated in figure 2, but may also be directly fluidly coupled to the flow control section 5. In figure 3, the fluid flow direction is indicated with a vector F, directing in two opposite directions. This is to indicate that the sample probe as depicted here works optimal in both flow directions. At its inlet end 12, the sample probe 3 has a fluid inlet 14 and a fluid outlet 15. In the current embodiment, the fluid inlet 14 and fluid outlet 15 open in opposite directions, and are in line, indicated by dotted line S. The fluid inlet 14 and fluid outlet 15 are here in line. Furthermore, in this embodiment the fluid inlet 14 and fluid outlet 15 have functionally the same cross sectional area, and in fact they here have the same shape. In the drawing, an inlet and an outlet are specifically references, but it should be clear that in fact in operation the opening that opens in the direction of the fluid flow is the inlet, and the opposite opening is the outlet. Thus, for optimal operation the dotted line S should be functionally parallel to the actual flow direction F. In this way, the inlet experiences an increased pressure due to the dynamic pressure, and the outlet would experience a reduced pressure due to the dynamic pressure. As a consequence of this, an increased fluid pressure exists at the fluid inlet, and a reduced fluid pressure exists at the fluid outlet 15. The fluid inlet 14 and fluid outlet

15 are fluidly coupled via a fast loop channel 16. The pressure differences urge the fluid through the fast loop channel 16.

Sample probe 3 in the current embodiment is elongated, with said fast loop channel running in a first branch 17 from the fluid inlet 14 to the sample probe outlet end 13. The fast loop channel 16 then makes a U-turn 18. Subsequently, the fast loop channel

16 has a second branch 19 that runs back to the sample probe inlet end 12 where it fluidly couples to the fluid outlet 15. Here, the first branch 17 and second branch 19 are straight channels. Furthermore, the first branch 17 and the second branch 19 run parallel. The sample probe 3 is elongated and has a longitudinal axis. The first branch 17 and second branch 19 here run parallel to the longitudinal axis. In the current embodiment, the sample probe 3 is cylindrical, in particular circle cylindrical.

With the fluid inlet 14 and the fluid outlet 15 in operation positioned as explained, the cryogenic fluid is urged through the fast loop channel 16. In this way, the composition of the fluid in the fast loop channel 16 is representative of the fluid in the fluid flow.

A sampling channel 20 is fluidly coupled to the fast loop channel 16, in particular at the U-turn 18. Sampling channel 20 has an outlet at the sample probe outlet end 13. In order to prevent pressure loss, causing boiling, and to provide sampling speed and thus potentially measuring speed, a cross sectional area of the sampling channel 20 is smaller than the cross sectional area of the fast loop channel 16. Furthermore, the sampling channel is straight, further reducing its volume. Sampling channel 20 is fluidly coupled, here via process insulation valve 4, to the flow control section 5.

We turn again to figure 1. The sampling channel 20 is fluidly coupled, here via the process insulation valve 4, to a flow control section inlet end 21. The flow control inlet end 21 is fluidly coupled to flow control outlet end 22 via flow control fluid line 23. At or shortly downstream of the inlet 21 of the flow control section 5, the collected fluid flow is here divided into a sample stream via conduit 23 and a further stream. That further stream ends in a restriction 24 to control its flow. The further stream is allowed to expand and vaporize in vaporizing space 25. The expanded and thus cooled vapour contacts the fluid line 23 in a heat-exchanging contact. Flow control fluid line 23 thus comprises at least one flow control branching line 24. Here, part of the quantity of sample fluid is allowed to vaporize onto a vaporizing space 25 of the flow control section 5. This controlled vaporization causes a cooling of the vaporizing space 25 and this prevents fluid in the flow control fluid line 23 from boiling. The flow control section further comprises a boil off gas outlet 26 for removing the vaporized part of the quantity of sample fluid. A sample of fluid at the flow control outlet 22 is subsequently provided to the heater section 6 via the thermal expansion section 7.

At the heater section 6, an oil heater is provided comprising an oil container 27 with a heater 10 extending in the oil container 27. A heater section fluid line 28 advances through the heated oil in the oil container 27. In an embodiment, the heater section fluid line at heater section inlet 29 has an expanding cross sectional area. In combination with the heated oil, this causes a flash vaporization of the sample flow. Via the heater section fluid line 28, the gaseous sample flow is transported to a measuring device 30.

It will also be clear that the above description and drawings are included to illustrate some embodiments of the invention, and not to limit the scope of protection. Starting from this disclosure, many more embodiments will be evident to a skilled person, like for instance kinematic reversal. These embodiments are within the scope of protection and the essence of this invention and are obvious combinations of prior art techniques and the disclosure of this patent

Reference numbers

1 sampling device

2 transfer line

3 sample probe

4 process insulation valve

5 flow control section

6 heater section

7 thermal expansion section

8 insulation jacket

9 fluid line

10 heating device

11 sample tab/process connection

12 sample probe inlet end

13 sample probe outlet end

14 fluid inlet

15 fluid outlet

16 fast loop channel

17 first branch

18 U turn

19 second branch

20 sampling channel

21 flow control section inlet end

22 flow control section outlet end

23 flow control section fluid line

24 flow control section restriction or orifice

25 flow control section vaporizing space

26 flow control section boil off gas outlet

28 heater section fluid line

29 heater section inlet

30 measuring device

31 valve flow channel or conduit L sample probe longitudinal direction F fluid flow direction

S sample probe inlet/outlet line

Claims

Claims

1. A sampling device for sampling a cryogenic fluid for measuring at least one

property, said sampling device comprising:

- a cold section comprising a sample probe extending into said cryogenic fluid for retrieving a quantity of said cryogenic fluid, said sample probe fluidly coupled to a flow control section, said flow control section comprising a cold fluid line for transferring said quantity of said cryogenic fluid to an outlet end of said fluid control section, said cold fluid line allowing splitting off a part of said quantity of said cryogenic fluid, leaving a sample, and vaporization said part of said quantity of said cryogenic fluid for cooling said sample and thus preventing boiling of said remaining sample in said cold fluid line;

- a heating section, fluidly coupled to said cold fluid line of said cold section for receiving said sample and comprising a heating device for bringing said sample in a gaseous phase at an outlet end, and said outlet end fluidly coupled to a measuring device for measuring said at least one property of said sample in said gaseous phase.

2. The sampling device according to claim 1, wherein said fluid line comprises a flow control branching line for said splitting off a part of said quantity of said cryogenic fluid, said flow control branching line comprising a vaporizing end for vaporizing at least part of said part of said quantity of said cryogenic fluid for cooling said sample downstream of said flow control branching line.

3. The sampling device according to any one of the preceding claims, further

comprising a thermal expansion section having an inlet end fluidly coupled to an outlet end of said flow control section and an outlet end fluidly coupled to an inlet end of said heating section, said thermal expansion section comprising an insulation coupling coupled to said flow control section and said heating section, and a flexible fluid line fluidly coupling said thermal expansion inlet and outlet and running inside said insulation coupling and comprising at least one bend for absorbing expansion and shrinkage between the flow control section and the heating section.

4. The sampling device according to any one of the preceding claims, wherein said sample probe comprises an inlet end and an outlet end, said inlet end comprising a fluid inlet and a fluid outlet which open in functionally opposite directions, a fast loop channel connecting said fluid inlet and said fluid outlet, and a sampling channel for retrieving said quantity of cryogenic fluid from said fast loop channel, said sampling channel comprising a sampling channel outlet at or near said sample probe outlet end.

5. The sampling device of claim 4, wherein said sampling channel has a smaller cross sections area than a cross sectional area of said fast loop channel, in particular said sampling channel has a cross sectional area which is 0.2-0.5 times said cross sectional area of said fast loop channel, more in particular 0.25-0.35 times.

6. The sampling device of claim 4 or 5, wherein said sample probe has an elongated shape having a longitudinal axis, wherein said fast loop channel comprises a first branch, a U turn and a second branch, said sampling channel at one end fluidly coupled to said U-tum.

7. The sampling device according to any one of the preceding claims, wherein said sample probe comprises a sample loop for said fluid, said one end of said sample loop comprising a first opening and an opposite end of said sample loop comprising a second opening, wherein said first and second opening are in line.

8. The sampling device according to any one of the preceding claims, wherein said flow control section comprises a metal core comprising a fluid channel providing said flow control section fluid line, a branching line provided with a restriction at or near its end and a container providing an evaporation space around said metal core, in particular said restriction provided at said inlet of said flow control section and inside said container.

9. The sampling device according to any one of the preceding claims, wherein said thermal expansion section comprises a fluid line having a length which is longer than a direct line connecting said flow control section outlet and said heater section inlet, in particular said fluid line has at least one bend, in particular said fluid line has an S-shaped for in operation absorbing and eliminating forces and material tension due to large temperature differences, in particular said fluid line has a cross sectional area which is between 0.1 and 0.01 times smaller than a cross sectional area of said flow control section fluid line.

10. The sampling device according to any one of the preceding claims, wherein said heating section is adapted for flash vaporizing said fluid sample, wherein heater section fluid line provides a cross section increase of between 10-100 times, in particular said heater section fluid line is coiled and comprises a static mixer adapted for providing a zero dead volume accumulator.

11. The sampling device according to any one of the preceding claims, wherein said heater section in operation is filled with a thermal oil and comprises an immersion heater for heating.

12. The sampling device according to any one of the preceding claims, wherein said heater section fluid line comprises a staggered static mixers for distributing heat of said thermal oil to said incoming and vaporized fluid, for mixing said vaporized fluid into a homogeneous gas sample.

13. A method for measuring a property of a flow of cryogenic fluid, comprising:

- providing a sample probe into said flow of cryogenic fluid for retrieving a quantity flow of flow of cryogenic fluid and which is representative of said flow of cryogenic fluid;

- transferring said quantity flow to a flow control section;

- vaporizing a part of said quantity flow, with a remaining flow forming a sample flow, said vaporizing cooling said sample flow for preventing boiling of said sample flow.

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