WO2025027238A1 - Method for measuring the pour point of a liquid body, and system for measuring the pour point of a liquid body - Google Patents

Abstract

The invention relates to a method for measuring (100) the pour point of a liquid body (2) using at least one microfluidic chip (10) comprising at least one microchannel (1), said method (100) comprising: - a step (110) of bringing the liquid body (2) into contact with a gas (3) inside the at least one microchannel (1) so as to form a liquid/gas interface (4); the gas (3) being at a predetermined pressure and the liquid body (2) being at an injection temperature; - a step (120) of measuring the movement of the interface (4), as a function of at least one predetermined temperature and at least one prestress; - a step (130) of determining the pour point of the liquid body (2) as a function of the at least one predetermined temperature and of an evolution in the movement of the interface (4).

Description

Description

TITLE: METHOD FOR MEASURING A POUR POINT OF A LIQUID BODY, AND SYSTEM FOR MEASURING A POUR POINT OF A LIQUID BODY

Technical field

[001] The invention relates to the field of microfluidics. In particular, the invention relates to a method for measuring a flow point of a liquid body.

[002] The invention further relates to a system for measuring a pour point of a liquid body.

Previous technique

[003] Hereinafter we describe the known prior art from which the invention was developed.

[004] In order to measure a pour point of a liquid body, the ASTM D97 standard and in particular the ASTM D97-2022 standard are known.

[005] In this standardized method, the sample is placed in a bath at controlled temperature (cold) and left to cool. Every 3 degrees the sample is removed and the bottle is turned over by a maximum of 90° (horizontal). The operator then checks whether the fluid flows or not under its own weight; the stress undergone by the liquid is therefore propositional to the density of said liquid, the diameter of the bottle and gravity. The pour point is defined as the temperature at which the fluid no longer flows.

[006] The main disadvantages of such a method, although standardized, lie in particular in a slow measurement which requires a full-time operator. The operator manually checks whether the fluid is flowing or not at regular temperature intervals. In addition, such a manual method centered on an operator is therefore unreliable, not very reproducible and not very repeatable.

[007] There is currently no standardized method or measurement method for automated measurements of a fluid pour point.

[008] Microfluidics allows to study the behavior of fluids in microchannels. A fluid can be described as simple or complex, single or multiphase. Thus, it is possible to study fluids and in particular the analysis of fluids at the micrometric scale. In particular, at this scale, the study of fluids is facilitated.

[009] In order to implement micrometric dimensions, microfluidic chips have appeared. They consist of microchannels connected together so as to perform a function. The microchannels are connected at the macroscopic scale using input and output ports. The diversity of chips currently lies in the design of the microchannels and in particular in the materials used to make them (glass, polymer, silicon). However, there are limits to the fluid handling capabilities, or to the design of complex chips, for example integrated into systems or with variable geometry.

[010] Documents have revealed the usefulness of microfluidics in the characterization of fluids.

[011] For example, document EP3047101 proposes a system for detecting the wax onset temperature (WAT) of a hydrocarbon fluid sample. However, this document is not interested in the behavior of the fluid and in particular its pour point.

[012] Similarly, document WO2022129400 proposes a system for controlling the temperature of a microfluidic chip comprising a Peltier module. Temperature can be a key parameter in determining the pour point of a fluid. However, this document does not make it possible to measure a pour point of a fluid.

[013] Document EP2954344 proposes a microfluidic device for parallelizing a pressure-volume-temperature analysis so that the pressure, temperature and volume analysis is carried out separately. Although this document allows for parallelization of measurements, it does not allow for measuring a flow point in an automated manner.

[014] Finally, document EP2384429 proposes a microfluidic device for regulating the movement of fluid in the channels. The movement is then regulated by a valve in order to be able to link the microfluidics to the sequencing of nucleic acids. However, this document is in no way interested in the flow point and even less in the measurement of a flow point. [015] Thus, today, current methods only consider the macroscopic scale to measure a pour point. In addition, these methods require the presence of an operator, numerous manipulations that can alter the results, little precision and relatively long measurement times. Furthermore, current developments in microfluidics that can provide the precision of their scale do not allow the measurement of a fluid pour point, nor the automation and parallelization of measurements. Indeed, microfluidics focuses on the analysis of fluids in various fields.

[016] Thus, there is a need for new methods of measuring a pour point at the micrometric scale which are automated, parallelized, precise and reproducible while avoiding the presence of an operator and particularly long measurement times (compared to the ASTM D97 standard).

[017] The invention aims to remedy the drawbacks of the prior art. In particular, the invention aims to propose a method for measuring a pour point, said method being automated, rapid, reliable, reproducible, repeatable and making it possible to measure a pour point on a micrometric scale while avoiding the continual presence of an operator.

Summary of the invention

[018] The invention aims to overcome these drawbacks. The following presents a simplified summary of selected aspects, embodiments and examples of the present invention for the purpose of providing a basic understanding of the invention. However, this summary does not constitute an exhaustive overview of all aspects, embodiments and examples of the invention. Its sole purpose is to present selected aspects, embodiments and examples of the invention in a concise form as an introduction to the more detailed description of the aspects, embodiments and examples of the invention which follow the summary.

[019] The invention relates in particular to a method for measuring a flow point of a liquid body using at least one microfluidic chip comprising at least one microchannel, said measurement method comprising:

- A step of bringing the liquid body into contact with a gas within the at least one microchannel so as to form a liquid/gas interface; the gas being at a predetermined pressure and the liquid body being at an injection temperature, A step of measuring the movement of the interface, as a function of at least one predetermined temperature and at least one constraint pressure;

A step of determining the flow point of the liquid body as a function of at least one predetermined temperature and a change in the movement of the interface during the step of measuring the movement of the interface.

[020] The applicant has developed a method for measuring a flow point of a liquid body taking microfluidics into consideration.

[021] Such a method makes it possible to determine a pour point of a liquid body. Furthermore, such a measurement method is capable of meeting the needs of the field. In particular, a measurement method according to the invention is reliable, reproducible and repeatable. It makes it possible to parallelize the measurements and automate them without the intervention of an operator. Furthermore, a method according to the invention is precise. Such a method makes it possible to do without the need for an operator. Furthermore, the method makes it possible to increase the prediction by increasing the statistics of the measurements. Such a method according to the invention therefore makes it possible to obtain statistically significant results. A method according to the invention is also faster because it makes it possible to carry out several measurements in a single operation.

[022] Thus, a method according to the invention makes it possible to monitor the evolution of an interface. In addition, such a method makes it possible to reduce the volumes used compared to the standardized method. The method makes it possible to guarantee the relevance and robustness of the measurements while being suitable for all formulations.

[023] Advantageously, such a method can also make it possible to measure other parameters such as precipitation and/or crystallization.

[024] According to other optional features of the method, the latter may optionally include one or more of the following features, alone or in combination:

- the liquid body is selected from a pure liquid, a mixture of liquids, a liquid solution, a dispersion and/or their mixture,

- the injection temperature is selected from an ambient temperature, a temperature between a solidification temperature of the liquid body and a boiling temperature of the liquid body, - the contacting step includes a gas injection step,

- the gas injection step is carried out co-currently, counter-currently, or perpendicularly to the flow of the liquid body,

- the gas is selected from rare gas, air, CO2, nitrogen, sulfur hexafluoride, and/or their mixture,

- the motion measurement step includes a gas injection stop step,

- the movement measurement step includes a step of modifying the temperature until a predetermined temperature is reached,

- the temperature modification step comprises cooling or heating the microfluidic chip and/or the at least one microchannel so as to reach the at least one predetermined temperature,

- at least one predetermined temperature is lower or higher than the injection temperature,

- the at least one predetermined temperature is a temperature gradient,

- at least one predetermined temperature is a constant temperature,

- the interface movement measurement step includes a gas reinjection step,

- the gas reinjection step is carried out at a constraint pressure, preferably at constant pressure,

- the step of measuring the movement of the interface comprises at least one step of at least one measurement of the evolution of the interface, the step of measuring the evolution of the interface comprises at least one comparison of the revolution of the interface as a function of at least one predetermined temperature,

- the interface motion measurement step is selected from optical detection, electrical detection, thermal detection and/or acoustic detection,

- the interface motion measurement step is repeated until a comparison of the interface evolution includes a measurement of the absence of interface evolution, - the pour point determination step includes measuring the absence of change in the liquid/gas interface,

- the pour point determination step is selected from optical detection, electrical detection, thermal detection and/or acoustic detection.

[025] According to a second object, the invention relates to a system for measuring a pour point comprising:

At least one microfluidic chip comprising at least one microchannel configured to bring a liquid body and a gas into contact according to a predetermined injection temperature and pressure, said at least one microchannel being further configured to convey a liquid/gas interface according to at least one predetermined temperature and a constraint pressure,

- At least one thermalization element configured to impose at least one predetermined temperature on said microfluidic chip or on at least one microchannel,

- At least one interface motion detection device configured to measure the evolution of the interface,

- At least one pour point determining device configured to measure the pour point of the liquid body.

[026] A system according to the invention makes it possible to measure a pour point.

[027] A system for measuring a pour point considering microfluidics makes it possible to determine a pour point of a liquid body whose measurements are precise, reliable, reproducible and repeatable. Such a system makes it possible to parallelize the measurements and automate them without the intervention of an operator. Furthermore, the system according to the invention makes it possible to do without the need for an operator. The system according to the invention also makes it possible to increase the prediction by increasing the statistics of the measurements and therefore makes it possible to obtain statistically significant results. The system according to the invention makes it possible to obtain measurements more quickly because it makes it possible to carry out several measurements in a single operation.

[028] Thus, a system according to the invention makes it possible to monitor the evolution of an interface. In addition, it makes it possible to reduce the volumes used compared to existing systems. The system according to the invention makes it possible to guarantee the relevance and robustness of the measurements while being suitable for all formulations.

[029] Advantageously, such a system can also make it possible to measure other parameters such as precipitation and/or crystallization.

[030] As further optional features of the system, the system may optionally include one or more of the following features, alone or in combination:

- the at least one input is configured to comprise a liquid body injection device and/or a gas injection device,

- the gas injection device is configured to be arranged in co-current, counter-current or perpendicular to the flow of the liquid body injection device,

- the at least one microchannel is configured to be wider than thin,

- the at least one microchannel is configured so that its width is strictly greater than its height,

- the at least one microchannel is configured so that its length is strictly greater than its width.

Brief description of the drawings

[031] Other characteristics and advantages of the invention will be better understood upon reading the description which follows and with reference to the appended drawings, given for illustrative purposes and in no way limiting.

[032] [Fig. 1] Figure 1 shows a diagram of a method for measuring a pour point according to one embodiment of the invention.

[033] [Fig. 2] Figure 2 represents a diagram of a contacting step according to an embodiment of the invention.

[034] [Fig. 3] Figure 3 shows a diagram of a motion measurement step according to one embodiment of the invention.

[035] [Fig. 4] Figure 4 shows a diagram of a system for measuring a point flow according to one embodiment of the invention.

[036] [Fig. 5] Figure 5 shows a diagram of a system for measuring a pour point according to one embodiment of the invention.

[037] [Fig. 6] Figure 6 shows a diagram of a system for measuring a pour point according to one embodiment of the invention.

[038] [Fig. 7A] Figure 7A shows a movement of an interface at constant temperature.

[039] [Fig. 7B] Figure 7B represents a movement of an interface according to a temperature gradient.

[040] [Fig. 8A] Fig. 8A shows a graph of one embodiment of a stepwise temperature change, the predetermined temperature being a constant temperature.

[041] [Fig. 8B] Fig. 8B shows a graph of one embodiment of a constant temperature change, the predetermined temperature being a temperature gradient.

[042] The figures do not necessarily respect the scales, in particular in thickness, and this is for illustration purposes.

[043] Aspects of the present invention are described with reference to flowcharts and/or functional diagrams of methods, apparatuses (systems) according to embodiments of the invention.

[044] In the figures, flowcharts and block diagrams illustrate the architecture, functionality and operation of possible implementations of systems, methods according to various embodiments of the present invention. In this regard, each block in the flowcharts or block diagrams may represent a system, a device, a module for implementing the specified function(s). In some implementations, the functions associated with the blocks may appear in a different order than that shown in the figures. For example, two blocks shown in succession may, in fact, be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order, depending on the functionality involved. Description of the embodiments

[045] Below, we describe a summary of the invention and the associated vocabulary, before presenting the drawbacks of the prior art, and then finally showing in more detail how the invention remedies them.

[046] The expression “predetermined pressure” may correspond to a pressure equal to, greater than or less than the constraint pressure.

[047] The expression “injection temperature” may correspond to a temperature equal to, greater than or less than a predetermined temperature.

[048] The term “fluid” within the meaning of the invention may correspond to a gas and/or a liquid.

[049] The term “liquid” within the meaning of the invention corresponds to any body capable of flowing under its own weight.

[050] The invention proposes to take into consideration the drawbacks of current methods for measuring a pour point. In particular, the invention proposes a method for measuring a pour point of a liquid body. For this, the invention proposes to implement microfluidics.

[051] Thus, the invention relates to a method for measuring a pour point of a liquid body using at least one microfluidic chip comprising at least one microchannel. The invention is neither limited by the size of a microfluidic chip nor by the number of microchannels. A method for measuring a pour point can be illustrated in connection with FIG. 1.

[052] A method 100 for measuring a flow point of a liquid body 2 using a microfluidic chip 10 comprising at least one microchannel 1 may comprise a step 110 of bringing a liquid body 2 into contact with a gas 3, a step 120 of measuring movement and a step 130 of determining the flow point of the liquid body 2.

[053] Furthermore, a method 100 for measuring a pour point of a liquid body 2 may comprise a step 105 for preparing a liquid body 2, a step 140 for controlling temperature, a step 150 for controlling pressure, and a step 160 for measuring time. [054] A method 100 for measuring a pour point of a liquid body 2 may comprise a step 105 for preparing a liquid body 2. A step 105 for preparing a liquid body 2 may be implemented using glassware and/or means commonly used in the field.

[055] A step of preparing 105 a liquid body 2 may comprise any means for obtaining a liquid. Preferably a liquid body at ordinary pressure and temperature, that is to say more preferably at atmospheric pressure and room temperature.

[056] Furthermore, a step of preparing 105 a liquid body 2 may comprise a step of mixing at least two liquids, at least one liquid and one gas, at least one liquid and one solid, at least one gas and one solid, at least two gases, at least two solids. Thus, a liquid body 2 may be simple, i.e. comprising a single element (a gas, a solid or a liquid) or complex, i.e. comprising at least two elements (identical or different). The invention is not limited by the number of elements present in the liquid body 2, however and preferably a liquid body 2 comprises at most 100 elements.

[057] Thus, a step 105 of preparing a liquid body 2 may comprise a melting, a liquefaction or even a sublimation followed by a liquefaction and/or a condensation followed by a melting or any other reaction making it possible to obtain a liquid. Obviously, if the liquid body 2 is already in the liquid state, it is not necessary to implement a step making it possible to obtain a liquid. Furthermore, a step 105 of preparing a liquid body may comprise a mixing step, preferably when the liquid body 2 is complex. Thus, preferably, a liquid body may be selected from a pure liquid, a mixture of liquids, a liquid solution, a dispersion (suspension, emulsion, foam), and/or their mixture.

[058] Furthermore, the invention is not limited by the type of body as long as it is liquid. For example, a body can be selected from a material, water, hydrocarbon, biological material, gas preferably CO2, bacterial suspension, food product, cosmetic product, and/or construction product.

[059] A preparation step 105 of a liquid body 2 makes it possible to obtain a body in its liquid form.

[060] A method of measuring 100 a pour point of a liquid body 2 can comprise a step of bringing the liquid body 2 into contact 110 with at least one gas 3, preferably with a gas 3. A step of bringing into contact 110 can be illustrated in connection with FIG. 2.

[061] A contacting step 110 makes it possible to form a liquid-gas or gas-liquid interface 4 preferably between the liquid body 2 and the gas 3. It should be noted that the expressions liquid/gas interface or gas/liquid interface within the meaning of the present invention can be used in a similar manner.

[062] A contacting step 110 may comprise a step 111 of injecting the liquid body 2 at an injection temperature, preferably into the microfluidic chip 10 and more preferably at at least one inlet 5 configured to receive a liquid body 2. The step 111 of injecting the liquid body 2 makes it possible to introduce a liquid body 2 into the microfluidic chip 10, preferably into the at least one microchannel 1. Advantageously, an injection temperature may be an ambient temperature or a temperature between a solidification temperature of the liquid body and a boiling temperature of the liquid body. Preferably, the injection temperature is a constant temperature.

[063] A contacting step 110 may comprise a step of verifying the homogeneity 112 of the liquid body, preferably in the case of a complex liquid body 2. Such verification may be selected from optical detection, electrical detection, thermal detection and/or acoustic detection.

[064] A contacting step may comprise a step 113 of injecting at least one gas 3, preferably a gas 3, preferably at a predetermined pressure and preferably into the microfluidic chip 10, preferably into the at least one microchannel 1 and more preferably at at least one inlet 5 configured to receive at least one gas 3. Advantageously, a predetermined pressure may correspond to a pressure allowing the injection of the gas 3. For example, a predetermined pressure may be at least 5 mbar, preferably at least 50 mbar. For example, a predetermined pressure may be at most 10 bar, preferably at most 5 bar. A predetermined pressure may for example be selected from values ranging from 5 mbar to 10 bar, preferably ranging from 50 mbar to 5 bar. Preferably, the injection step 113 of the gas 3 is carried out at controlled pressure, preferably at constant pressure and even more preferably at atmospheric pressure (for example close to 1 bar at atmospheric pressure +/- 15% or approximately 2 bar of absolute pressure). The person skilled in the art will however know that such a predetermined pressure can be adapted according to the viscosity of the liquid body, the length of the at least one microchannel 1, the material(s) constituting the chip 10, the geometry of the at least one microchannel 1, etc. The step 113 of injecting a gas 3 makes it possible to introduce a gas 3 into the microfluidic chip 10, preferably into the at least one microchannel 1. This step 113 of injecting gas 3 can be carried out in co-current, counter-current or in a current perpendicular to the flow of the liquid body 2.

[065] Furthermore, a gas 3 can be selected from a non-reactive gas (i.e. inert) with the liquid body 2. Preferably, a gas 3 that is little or not at all miscible with the liquid body 2. For example, a gas 3 can be selected from a rare gas (Helium, Neon, Argon, Krypton, Xenon, Radon), air, CO2, nitrogen, sulfur hexafluoride, and/or their mixture.

[066] A contacting step 110 may also comprise a step 114 of verifying the formation of the liquid/gas interface 4. A step 114 of verifying the formation of the liquid/gas interface 4 may be selected from: electrical detection, optical detection, thermal detection and/or acoustic detection.

[067] A method 100 for measuring a pour point of a liquid body 2 may comprise a step 120 for measuring movement of the interface 4, preferably as a function of at least one predetermined temperature and at least one constraint pressure. A step 120 for measuring movement of the interface 4 may be illustrated in connection with FIG. 3.

[068] A motion measurement step 120 may include a step of stopping injection 121 of gas 3. This makes it possible to define a location of the interface 4.

[069] A motion measurement step 120 may comprise a step 122 of modifying the temperature, preferably the injection temperature, until a predetermined temperature is reached. A predetermined temperature may be higher, lower or equal to the injection temperature, preferably lower or higher than the injection temperature. Thus, a step 122 of modifying the temperature may allow cooling, heating or maintaining the temperature of the at least one microchannel 1 and/or the microfluidic chip 10 so as to reach a predetermined temperature. A constant temperature may correspond to a precise temperature value as opposed to a temperature gradient which may correspond to an interval (i.e. set of values) of temperature. Furthermore, a step 122 of modifying the temperature may be a constant or gradient modification of the temperature. Thus, a predetermined temperature can be a temperature gradient or a constant temperature. Advantageously, a predetermined temperature can be determined by successive testing up to the step 130 of determining the pour point of the liquid body 2. Furthermore, in a particular but non-limiting embodiment of the invention, the aging of a liquid body 2 whose structure changes over time can also be studied (i.e. freezes at the same injection temperature). An example of a step 122 of modifying the temperature until a predetermined temperature is reached can be illustrated in connection with FIG. 8A or 8B. In FIG. 8A, the temperature is modified in stages, the predetermined temperature then corresponds to a constant temperature. In FIG. 8B, the temperature is modified constantly, the predetermined temperature then corresponds to a temperature gradient.

[070] Advantageously, a movement measurement step 120 can comprise a latency step 123 until stabilization of the modified temperature (reaching of at least one predetermined temperature).

[071] A step of measuring movement 120 of the interface 4 may comprise a step of reinjection 124 of gas 3, preferably after the latency step 123. This makes it possible to create or not a movement in the at least one microchannel 1 of the interface 4 preferably as a function of the modified temperature. Advantageously, the step of measuring movement 120 and preferably of reinjection 124 of gas 3 may be carried out at a constraint pressure. A constraint pressure may be a constant pressure. A constraint pressure may be greater than, less than or equal to a predetermined pressure. Advantageously, the constraint pressure may be close to (i.e. less than 15% variation, preferably less than 10% variation) a pressure standardized according to the ASTM D97 standard and preferably ASTM D97-2022. Preferably, the constraint pressure is a function of the constraint at the interface 4, for example ranging from 10 to 1000 Pa.

[072] The movement measurement step 120 may comprise at least one step 125 of at least one measurement of the evolution of the interface 4. By evolution, is meant within the meaning of the invention a movement, that is to say a displacement or the absence of displacement. Preferably, the step 125 of at least one measurement of the evolution of the interface 4 may comprise at least one comparison 126 of the evolution of the interface 4 as a function of the modified temperature and of the constraint pressure, preferably as a function of the modified temperature and more preferably as a function of the modified temperature until reaching the predetermined temperature. The comparison may be carried out by relative to the displacement of the interface 4 between each gas injection step 3 and as a function of the modified and/or predetermined temperature.

[073] For example, at the start of the measurement method, the interface 4 is formed in the contacting step 110, then in the measurement step, the gas injection is stopped and the temperature is changed until reaching a predetermined temperature. The movement or absence of movement of the interface 4 is then determined. The movement measurement step 120 of the interface 4 can be selected from optical detection, electrical detection, thermal detection and/or acoustic detection.

[074] Furthermore, the step of measuring movement 120 of the interface 4 can be repeated OK until the step of comparing 126 the evolution of the interface 4 includes a measurement of the absence NOK of evolution of the interface 4. The comparison can be carried out by optical detection, electrical detection, thermal detection and/or acoustic detection.

[075] Thus, the step of measuring movement 120 of the interface 4 can comprise, as disclosed above, a step of stopping 121 the injection of gas 3 and of reinjection 124 of gas 3 at each new measurement of movement 120 of the interface 4. Also, the step of measuring movement 120 of the interface 4 can comprise a step of modifying the temperature or the predetermined temperature at each new measurement of movement of the interface 4. Thus, the step of measuring movement 120 of the interface 4 can comprise a modification of the temperature and preferably of the predetermined temperature until reaching a new predetermined temperature at each new measurement of movement of the interface 4. Advantageously, the latency step 123 is also repeated for each new measurement of movement of the interface 4.

[076] An example may be illustrated in connection with Figure 7A or Figure 7B.

[077] A method 100 for measuring a pour point of a liquid body 2 may comprise a step 130 for determining the pour point of the liquid body 2, preferably as a function of at least one predetermined temperature and of the evolution of movement of the interface 4 during the step 120 for measuring movement of the interface 4.

[078] The determining step 130 may also be a function of the constraint pressure. A determining step 130 of the pour point of the liquid body 2 may also be illustrated in connection with FIG. 3. [079] A step 130 of determining the pour point of the liquid body 2 may comprise a step of measuring the absence of movement and preferably the absence of evolution 131 of the interface 4. Advantageously, the step 130 of determining the pour point of the liquid body 2 may be selected from optical detection, electrical detection, thermal detection and/or acoustic detection.

[080] Again, an example may be illustrated in connection with Figure 7A or Figure 7B.

[081] An optical detection can be selected from: refraction, reflection or diffraction of a light source (e.g. diiodine, laser, mono or polychromatic light), video analysis, image analysis (by difference or correlation), by colorimetry

[082] An electrical detection can be selected from: measurement of resistance, capacitance, impedance or conductivity at zero frequency or at a finite frequency.

[083] Thermal detection can be selected from: infrared absorption or emission, by thermocouple, thermal conductivity, specific heat, thermal resistance.

[084] An acoustic detection can be selected from: ultrasound, attenuation, re-election, election or diffraction of a sound or ultrasonic signal, reverberation, sound resonance.

[085] In addition, optical, thermal, electrical and/or acoustic detection may be continuous and/or local (one-off).

[086] Returning to FIG. 1 , a method 100 for measuring a pour point of a liquid body 2 may comprise a temperature control step 140 . A temperature control step 140 may be implemented by any means for controlling the temperature, for example, a Peltier assembly, a Peltier element, a temperature probe, and/or a thermostatted bath. Furthermore, the temperature may correspond to the injection temperature, the modified temperature, and/or the predetermined temperature.

[087] A method 100 for measuring a pour point of a liquid body 2 may also comprise a pressure control step 150. A pressure control step 150 may be implemented by any means making it possible to control the pressure, for example, a pressure controller linked to a pressure sensor. Furthermore, the pressure may correspond to the predetermined pressure and/or the constraint pressure.

[088] A method 100 for measuring a pour point of a liquid body 2 may also comprise a time measurement step 160. A time measurement step 160 is preferably carried out between the step 120 for measuring movement of the interface 4 and the step 130 for determining the pour point of the liquid body 2. This makes it possible to specify the method 100. This also makes it possible to specify the durations of application of pressure and/or temperature. Furthermore, such a step 160 may be implemented by any means for measuring time, for example using a stopwatch, a clock, preferably an electronic clock.

[089] Furthermore, and in a completely advantageous manner, the method 100 for measuring a pour point of a liquid body 2 can preferably be repeated for the same liquid body 2. This makes it possible to ensure the precision, reproducibility and repeatability of the method. The method 100 can for example be repeated according to a repetition ranging from 1 to 3 times, preferably from 1 to 5 times and more preferably from 1 to 10 times. Advantageously, the method may not be repeated while being precise, reproducible and repeatable. Indeed, the method makes it possible to carry out several measurements at different temperatures in a single operation. Also, the measurement method makes it possible to carry out several measurements at different temperatures and to replicate each of these measurements in a single operation.

[090] Advantageously, a method for measuring 100 a pour point of a liquid body 2 can be an automated method. This also makes it possible to contribute to saving time and to the need of an operator.

[091] Advantageously, a method for measuring 100 a pour point of a liquid body can be a parallel method.

[092] A measurement method 100 according to the invention makes it possible to increase the statistics of the measurements and consequently their predictive nature. A method according to the invention also makes it possible to carry out several tests at different temperatures in a single operation. A method 100 according to the invention makes it possible to carry out several measurements at different temperatures and to replicate each of these measurements in a single operation.

[093] According to another aspect, the invention relates to a system for measuring a pour point of a liquid body. [094] A system for measuring a pour point of a liquid body may be illustrated in connection with Figure 4, 5 or 6.

[095] A system 200 for measuring a pour point of a liquid body may comprise a microfluidic chip 10.

[096] A microfluidic chip 10 may be configured to comprise at least one microchannel 1 configured to bring a liquid body 2 and a gas 3 into contact. A microchannel 1 may be configured to convey a liquid/gas interface 4 according to at least one modified and/or predetermined temperature and/or according to at least one predetermined pressure and/or a constraint pressure.

[097] A microfluidic chip 10 may be configured to comprise at least one inlet 5. An inlet 5 may be configured to introduce a liquid body 2 and/or a gas 3 into said microfluidic chip 10, preferably into the at least one microchannel 1. Advantageously, an inlet 5 may be configured to comprise a device 51 for injecting a liquid body 2. Advantageously, an inlet 5 may be configured to comprise a device 52 for injecting a gas 3. A device 52 for injecting a gas 3 may be configured to be arranged in co-current, counter-current or perpendicular to the flow of the device 51 for injecting a liquid body 2.

[098] A microfluidic chip 10 may be configured to comprise at least one outlet 6. An outlet 6 may be configured to discharge a liquid body 2 and/or a gas 3 from the microfluidic chip 10.

[099] A microfluidic chip 10 may be configured to comprise at least one microchannel 1 , preferably at least 2 microchannels 1 , more preferably at least 5 microchannels 1 and more preferably at least 10 microchannels 1 . A microfluidic chip 10 may be configured to comprise at most 1000 microchannels 1 , preferably at most 800 microchannels 1 and more preferably at most 500 microchannels 1 . A microfluidic chip 10 may be configured to comprise between 1 and 1000 microchannels 1 , preferably between 2 and 800 microchannels 1 , more preferably between 5 and 500 microchannels 1 and more preferably between 10 and 500 microchannels 1 .

[100] Furthermore, the at least one microchannel 1 may be configured to be wider than thin (i.e. wider than thick, the thickness of which is less than the width). Preferably, the width/height ratio may be greater than or equal to 0.1. The width/height ratio may be less than or equal to 20, preferably less than or equal to 10. Furthermore, the at least one microchannel 1 can be configured so that its width is strictly greater than its height. The at least one microchannel 1 can be configured so that its length is strictly greater than its width.

[101] At least one microchannel 1 may be configured to comprise at least one injection hole 53 (figure 6), preferably the at least one injection hole 53 is configured to be arranged perpendicular to the flow of the liquid body 2.

[102] In a particular but non-limiting embodiment of the invention, the at least one microchannel 1 can be configured to be arranged in a rectilinear manner between the at least one inlet 5 and the at least one outlet 6.

[103] In a particular but non-limiting embodiment of the invention, a microfluidic chip 10 can be configured to comprise n microchannels 1, said microchannels 1 being able to be configured to be arranged in a rectilinear manner between the at least one inlet 5 and the at least one outlet 6 and in a parallel manner between them and/or equidistant from each other or two by two.

[104] Furthermore, a microfluidic chip 10 is not limited within the meaning of the invention by its dimensions.

[105] A microfluidic chip 10 may be disposable or reusable.

[106] A system 200 for measuring a pour point of a liquid body 2 may comprise at least one thermalization element 7. A system for measuring a pour point of a liquid body may comprise at most 4 thermalization elements 7. A system for measuring a pour point of a liquid body may comprise between at least one thermalization element and at most 4 thermalization elements 7, preferably between at least one thermalization element 7 and at most 3 thermalization elements 7 and more preferably between at least one thermalization element 7 and at most 2 thermalization elements 7. At least one thermalization element 7 may be configured to impose at least one predetermined temperature on the microfluidic chip 10 and/or on the at least one microchannel 1 and/or to modify at least one temperature, preferably at least one predetermined temperature. A thermalization element 7 can be selected from: a Peltier element, a Peltier assembly, liquid nitrogen and/or a thermostatic bath.

[107] A system 200 for measuring a flow point of a liquid body may comprise at least one device 11 for detecting movement of the interface 4. A A motion detection device 11 of the interface 4 may be configured to measure the evolution of the interface 4. A motion detection device 11 of the interface 4 may be selected from an optical detector, an electrical detector, a thermal detector and/or an acoustic detector.

[108] A system 200 for measuring a pour point of a liquid body may comprise at least one device 14 for determining a pour point of a liquid body. At least one device 14 for determining a pour point of a liquid body may be configured to measure the pour point of a liquid body. A device 14 for determining a pour point of a liquid body 2 may be selected from an optical detector, an electrical detector, a thermal detector and/or an acoustic detector.

[109] In a non-limiting embodiment of the invention, the device 11 for detecting movement of the interface 4 and the device 14 for determining the flow point of a liquid body 2 are configured to be common or distinct.

[1 10] A system 200 for measuring a pour point of a liquid body may comprise a device 13 for controlling the homogeneity of the liquid body 2. A device 13 for controlling the homogeneity of a liquid body 2 may be configured to check the homogeneity of a liquid body 2, preferably when a liquid body 2 is said to be complex within the meaning of the invention.

[1 11 ] A system 200 for measuring a pour point of a liquid body may comprise a control device 12 of the interface 4. A control device 12 of the interface 4 may be configured to verify the formation of a gas/liquid interface 4.

[1 12] A system 200 for measuring a pour point of a liquid body may comprise a temperature control device 8. A temperature control device 8 may be configured to check and/or measure at least one injection temperature and/or at least one modified temperature and/or at least one predetermined temperature.

[1 13] A system 200 for measuring a pour point of a liquid body may comprise a pressure control device 9. A pressure control device 9 may be configured to check and/or measure at least one predetermined pressure and/or a constraint pressure.

[1 14] The invention may be the subject of numerous variants and applications other than those described above. In particular, unless otherwise indicated, the different structural and functional features of each of the implementations described above should not be considered as combined and/or closely and/or inextricably linked to each other, but on the contrary as simple juxtapositions. Furthermore, the structural and/or functional features of the different embodiments described above may be the subject in whole or in part of any different juxtaposition or any different combination.

Claims

Claims 1. Method for measuring (100) a flow point of a liquid body (2) using at least one microfluidic chip (10) comprising at least one microchannel (1), said measuring method (100) comprising: A step of bringing (1 10) the liquid body (2) into contact with a gas (3) within the at least one microchannel (1) so as to form a liquid/gas interface (4); the gas (3) being at a predetermined pressure and the liquid body (2) being at an injection temperature, A step of measuring movement (120) of the interface (4), as a function of at least one predetermined temperature and at least one constraint pressure; A step of determining (130) the flow point of the liquid body (2) as a function of at least one predetermined temperature and a change in movement of the interface (4) during the step of measuring movement (120) of the interface (4). 2. Measuring method (100) according to claim 1 characterized in that the liquid body (2) is selected from a pure liquid, a mixture of liquids, a liquid solution, a dispersion and/or their mixture. 3. Measuring method (100) according to claim 1 or 2 characterized in that the injection temperature is selected from an ambient temperature, a temperature between a solidification temperature of the liquid body (2) and a boiling temperature of the liquid body (2). 4. Measuring method (100) according to one of the preceding claims, characterized in that the contacting step (110) comprises a step of injecting (113) a gas (3). 5. Measuring method (100) according to claim 4 characterized in that the gas injection step (113) is carried out in co-current, counter-current, or current perpendicular to the flow of the liquid body (2). 6. Measuring method (100) according to one of the preceding claims, characterized in that the gas (3) is selected from rare gas, air, CO2, nitrogen, sulfur hexafluoride, and/or their mixture. 7. Measuring method (100) according to one of the preceding claims, characterized in that the movement measurement step (120) comprises a step of stopping (121) the injection of gas (3). 8. Measuring method (100) according to one of the preceding claims, characterized in that the movement measuring step (120) comprises a step of modifying (122) the temperature until reaching at least one predetermined temperature. 9. Measuring method (100) according to claim 8 characterized in that the step of modifying (122) the temperature comprises cooling or heating the microfluidic chip (10) and/or the at least one microchannel (1) so as to reach the at least one predetermined temperature. 10. Measuring method (100) according to one of the preceding claims, characterized in that the at least one predetermined temperature is lower or higher than the injection temperature. 11. Measuring method (100) according to one of the preceding claims, characterized in that the at least one predetermined temperature is a temperature gradient. 12. Measuring method (100) according to one of the preceding claims, characterized in that the at least one predetermined temperature is a constant temperature. 13. Measuring method (100) according to one of the preceding claims, characterized in that the step of measuring (120) the movement of the interface (4) comprises a step of reinjection (124) of gas (3). 14. Measuring method (100) according to claim 13 characterized in that the step of reinjection (124) of gas (3) is carried out at a constraint pressure, preferably at constant pressure. 15. Measuring method (100) according to one of the preceding claims, characterized in that the step of measuring (120) the movement of the interface (4) comprises at least one step (125) of at least one measurement of the evolution of the interface (4). 16. Measuring method (100) according to claim 15 characterized in that the step of measuring the evolution (125) of the interface (4) comprises at least one comparison (126) of the evolution of the interface (4) as a function of at least one predetermined temperature. 17. Measuring method (100) according to one of the preceding claims, characterized in that the step of measuring movement (120) of the interface (4) is selected from optical detection, electrical detection, thermal detection and/or acoustic detection. 18. Measuring method (100) according to one of the preceding claims, characterized in that the step of measuring movement (120) of the interface (4) is repeated (OK) until a comparison (126) of the evolution of the interface (4) includes a measurement of the absence (NOK) of evolution of the interface (4). 19. Measuring method (100) according to one of the preceding claims, characterized in that the step of determining (130) the pour point comprises a measurement of the absence of evolution (131) of the liquid/gas interface (4). 20. Measuring method (100) according to one of the preceding claims, characterized in that the step of determining (130) the pour point is selected from optical detection, electrical detection, thermal detection and/or acoustic detection. 21. System (200) for measuring a pour point comprising: At least one microfluidic chip (10) comprising at least one microchannel (1) configured to bring a liquid body (2) and a gas (3) into contact according to a predetermined injection temperature and pressure, said microchannel (1) being further configured to convey a liquid/gas interface (4) according to at least one predetermined temperature and a constraint pressure, At least one thermalization element (7) configured to impose at least one predetermined temperature on said microfluidic chip (10) or on the at least one microchannel (1), At least one detection device (11) for movement of the interface (4) configured to measure the evolution of the interface (4), - At least one pour point determination device (14) configured to measure the pour point of the liquid body (2). 22. System (200) for measuring a pour point according to claim 21 characterized in that the at least one microfluidic chip (10) comprises at least one inlet (5) configured to comprise a device (51) for injecting a liquid body (2) and/or a device (52) for injecting a gas (3). 23. System (200) for measuring a pour point according to claim 22 characterized in that the gas (3) injection device (52) is configured to be arranged in co-current, counter-current or perpendicular to the flow of the injection device (51) of a liquid body (2). 24. System (200) for measuring a pour point according to one of claims 21 to 23, characterized in that the at least one microchannel (1) is configured to be wider than thin. 25. System (200) for measuring a pour point according to one of claims 21 to 24, characterized in that the at least one microchannel (1) is configured so that its width is strictly greater than its height. 26. System (200) for measuring a pour point according to one of claims 21 to 25, characterized in that the at least one microchannel (1) is configured so that its length is strictly greater than its width.