Real-time nondestructive monitoring device for moisture occurrence form of sample in heat-moisture treatment process

Abstract

The utility model discloses a real-time lossless monitoring device for the moisture occurrence form of a sample in the heat-moisture treatment process, the monitoring device comprises a nuclear magnetic resonance spectrometer (N1), a hot and humid air flow generating unit (N2) and an upper computer (N3), the hot and humid air flow is introduced into a probe part of the nuclear magnetic resonance spectrometer, and the moisture occurrence form of the sample can be monitored in real time on the premise of realizing the pretreatment of the lossless sample. On-line monitoring of the change rule of the proton relaxation spectrum of the sample under the conditions of specific temperature and humidity in the processes of thermophysics, thermochemistry and the like is carried out, so that the structure-function relationship between internal component migration, structural change and the like of the sample under the same environmental conditions in each process is disclosed; and environmental condition regulation and control and component migration process monitoring of the sample in a specific heat-moisture treatment process are facilitated. The humidity and temperature of the humid and hot airflow generated by the humid and hot airflow generation unit can be controlled in real time through the upper computer, so that the occurrence form of moisture in the sample in different humid and hot treatment processes is investigated.

Description

Technical Field

[0001] The utility model relates to the field of tobacco processing technology, in particular to a real-time non-destructive monitoring device for the moisture storage form of a sample during a wet heat treatment process. Background Art

[0002] Nuclear magnetic resonance technology is an effective tool for qualitative or quantitative analysis of the composition, structure, and tissue morphology of the sample to be tested based on the proton's absorption level of radio frequency radiation. According to Bohr's quantum theory, each atom consists of a positively charged nucleus and a number of negatively charged electrons moving around the nucleus. The magnetic nucleus has a spin magnetic field. When there is no external magnetic field, the nuclear spin is disordered and the macroscopic magnetic moment of the spin system is zero; when there is an external magnetic field, the microscopic magnetic moment is arranged in order along the direction of the magnetic field and has a macroscopic magnetization intensity along the direction of the external magnetic field. When the external action stops, the non-equilibrium state of the spin system cannot be maintained and it recovers to the equilibrium state. The process of restoring the spin system from an unbalanced state to an equilibrium state is called a relaxation process, and the time required for the recovery process is the relaxation time. The difference in relaxation time can be used to distinguish the water storage form in the sample.

[0003] In the fields of biomass, food, medicine, tobacco, etc., raw materials will go through multiple wet heat treatment processes, such as common extraction, drying, moisture resurgence, baking, mildew protection, etc., and the moisture content of tobacco in each process changes nonlinearly and time-varyingly. In addition, under special conditions such as ocean transportation, high temperature and high humidity environment, storage and transportation, and shelf life product quality are closely related to environmental conditions. Therefore, studying the moisture storage form and migration process in the wet heat treatment process of samples, and revealing the migration laws of various forms of moisture in samples under specific environmental conditions from a molecular level, is of great significance to achieve precise control of wet heat treatment processing technology and improve product quality assurance capabilities.

[0004] The existing nuclear magnetic resonance technology can meet the needs of sample testing under room temperature conditions, but cannot realize the function of online monitoring of the proton relaxation spectrum of samples under a certain temperature and humidity environment, that is, it lacks the ability to evaluate the moisture storage form and migration process in the sample wet heat treatment process.

[0005] Therefore, it is desirable to use nuclear magnetic resonance technology to detect the moisture storage form and migration process in real time during the wet heat treatment process of samples.

[0006] In order to solve the above problems, the present utility model is proposed. Utility Model Content

[0007] The monitoring device of the utility model includes a nuclear magnetic resonance instrument, a moist and hot airflow generating unit and a host computer. By introducing moist and hot airflow into the probe part of the nuclear magnetic resonance instrument, it can realize the online monitoring of the proton relaxation spectrum change law of the sample under specific temperature and humidity conditions during the process of thermal physics, thermochemistry, etc. without damaging the sample pretreatment, thereby revealing the structure-activity relationship between the environmental conditions and the internal component migration and structural changes of the sample in each process, which is helpful to carry out the environmental condition regulation and component migration process monitoring of the sample in a specific moist and hot treatment process. The humidity and temperature of the moist and hot airflow generated by the moist and hot airflow generating unit can be controlled in real time through the host computer, so as to examine the water storage form in the sample during different moist and hot treatment processes.

[0008] The utility model provides a real-time nondestructive monitoring device for the moisture storage form of a sample during a wet heat treatment process, which comprises a nuclear magnetic resonance instrument N1, a wet heat airflow generating unit N2 and a host computer N3.

[0009] The nuclear magnetic resonance instrument N1 includes a nuclear magnetic resonance instrument probe; the nuclear magnetic resonance instrument probe includes a probe tube 1 and a sample chamber 2 located in the probe tube 1, the sample chamber 2 contains a sample to be tested, and the bottom of the probe tube 1 has an air flow inlet 3;

[0010] The humid hot airflow generating unit N2 generates humid hot airflow, which enters the probe tube 1 through the airflow inlet 3 and contacts the sample to be tested in the sample chamber 2 to perform humid heat treatment on the sample. This enables real-time non-destructive monitoring of the moisture state of the sample during the humid heat treatment process;

[0011] The host computer N3 controls the temperature and humidity of the hot and humid airflow generated by the hot and humid airflow generating unit N2.

[0012] The humid hot air flow refers to gas with a certain humidity and temperature. The humidity and temperature of the humid hot air flow are determined according to actual needs during the specific test process.

[0013] Preferably, the hot and humid airflow generating unit comprises a water tank 13, a bubble generating device 14, a mixing chamber 15, a first heater 16 and a hot and humid airflow output pipeline 17;

[0014] The bubble generating device 14 is located at the bottom of the water tank 13, and the bubble generating device 14 is used to generate gas;

[0015] The water tank 13 contains water for generating saturated wet steam at a specific temperature;

[0016] The first heater 16 is located in the water tank 13 and is used to provide heat to the water and regulate the water temperature in the water tank 13;

[0017] The mixing chamber 15 is used to gather the humidified and heated hot and humid airflow;

[0018] The hot and humid airflow in the mixing chamber 15 is transported to the airflow inlet 3 through the hot and humid airflow output pipeline 17 .

[0019] Preferably, the hot and humid air flow outlet of the hot and humid air flow output pipeline 17 and the air flow inlet 3 are provided with an air flow inlet temperature sensor 5 and an air flow inlet humidity sensor 6, and the air flow inlet temperature sensor 5 and the air flow inlet humidity sensor 6 are respectively connected to the host computer N3, and the air flow inlet temperature sensor 5 and the air flow inlet humidity sensor 6 collect the temperature and humidity parameters of the hot and humid air flow entering the sample chamber 2 in real time, and feed back the temperature and humidity parameters of the hot and humid air flow to the host computer N3, and the host computer N3 controls the hot and humid air flow generating unit N2 to adjust the temperature and humidity parameters of the generated hot and humid air flow in real time.

[0020] Preferably, the air flow inlet temperature sensor 5 and the air flow inlet humidity sensor 6 are fixed by a sensor fixing ring 12 and / or a sensor fixing tube 20. The fixing form of the sensor can be selected according to the actual situation.

[0021] Preferably, the hot and humid air flow output pipeline 17 also has a delivery pipeline temperature sensor 19 and a delivery pipeline temperature controller 22, and the delivery pipeline temperature sensor 19 and the delivery pipeline temperature controller 22 are connected to the host computer N3. The delivery pipeline temperature sensor 19 collects the temperature information of the hot and humid air flow output pipeline 17 in real time, and transmits the collected information to the host computer N3. The host computer N3 further controls the temperature of the hot and humid air flow output pipeline 17 through the delivery pipeline temperature controller 22.

[0022] Preferably, the water tank 13 also has a water tank temperature sensor 23 and a water tank temperature controller 24, and the water tank temperature sensor 23 and the water tank temperature controller 24 are connected to the host computer N3. The water tank temperature sensor 23 collects the temperature information of the water tank 13 in real time and transmits the collected information to the host computer N3. The host computer N3 further controls the temperature of the water tank 13 through the water tank temperature controller 24.

[0023] Preferably, the humid hot air flow generating unit further comprises a second heater 25, which is located in the air chamber and is used to heat the air in the air chamber. The heated dry hot air is delivered to the air flow inlet 3 via an air delivery pipeline 26. A relay 21 is provided between the air delivery pipeline 26 and the humid hot air flow output pipeline 17. The relay 21 is connected to the host computer N3, and the host computer N3 switches the type of gas delivered to the air flow inlet 3 to be humid hot air flow or dry hot air through the relay 21. That is to say, according to demand, the humid hot air flow output pipeline 17 can be opened and the air through the air delivery pipeline 26 can be closed, so as to deliver humid hot air flow to the air flow inlet 3. On the contrary, the humid hot air flow output pipeline 17 can be closed and the air through the air delivery pipeline 26 can be opened, so as to deliver dry hot air to the air flow inlet 3.

[0024] Preferably, the air delivery pipeline 26 is provided with a second flow controller 27, and the second flow controller 27 is used to control the flow rate of the delivered dry hot air gas.

[0025] Preferably, the hot and humid air flow output pipeline 17 is provided with a first flow controller 18, and the first flow controller 18 is used to control the flow rate of the delivered hot and humid air flow.

[0026] Preferably, there is a heat-insulating material outside the humid hot air flow output pipeline 17. The purpose of the heat-insulating material is to keep the humid hot air flow output pipeline 17 warm and prevent the temperature of the humid hot air flow in the humid hot air flow output pipeline 17 from decreasing.

[0027] Preferably, a heat-insulating layer 4 is provided on the outside of the airflow inlet 3 to ensure that there is no heat loss in the process of the airflow entering the probe tube 1 .

[0028] Preferably, the chamber wall and / or bottom of the sample chamber 2 is provided with openings 7, and the airflow enters the sample chamber 2 through the openings 7 and contacts the sample to be tested in the sample chamber 2, so as to facilitate full contact between the sample and the external airflow, and more truly restore the gas-solid two-phase interaction state during the wet heat treatment process.

[0029] Preferably, the shape of the opening 7 includes but is not limited to a circle, a triangle or a quadrilateral.

[0030] Preferably, the probe tube 1 is further provided with a heat tracing aid 8 on one side close to the airflow inlet 3, and the heat tracing aid 8 can provide heat to prevent the humid hot airflow from condensing after entering the sample chamber 2, thereby ensuring that the humid hot gas and the sample to be tested can fully contact each other.

[0031] Preferably, the shape of the sample chamber 2 includes but is not limited to a cylinder, a cube, etc.

[0032] Preferably, the probe tube 1 also has an insulating tube 9 and a heat tracing tube 10 on its periphery. The insulating tube 9 is used to keep the hot and humid airflow in the probe tube 1 warm, while the heat tracing tube 10 is used to provide heat. The two tubes together ensure the temperature of the hot and humid airflow in the probe tube 1, thereby ensuring the temperature of the hot and humid airflow that enters the sample chamber 2 and contacts the sample to be tested. In addition, another function of the insulating tube 9 is to protect the magnet of the nuclear magnetic resonance instrument from being affected by the temperature of the hot and humid airflow in the probe tube, thereby ensuring that the magnet of the nuclear magnetic resonance instrument is in a reliable and stable operating state.

[0033] Preferably, the NMR probe further comprises a probe extension tube 11. In order to ensure that the hot and humid airflow can fully contact the sample to be tested in the sample chamber and ensure the stability of the test conditions, the length of the probe tube can be appropriately extended by the probe extension tube 11.

[0034] Preferably, the NMR probe also includes: probe frame cover plate, frame plate, sample chamber cover, sample chamber connecting rod, probe frame waveguide, probe frame waveguide cover, cap, positioning block and fixing device and other common parts of NMR probe. In addition, the NMR also includes other common parts such as magnets that generate magnetic fields in addition to the NMR probe.

[0035] The airflow output by the moist and hot airflow generating unit is communicated with the nuclear magnetic resonance instrument probe of the utility model, so as to provide reliable environmental testing conditions for the samples in the sample chamber inside the probe.

[0036] Using the monitoring device of the utility model, the real-time non-destructive monitoring method of the moisture state of the sample during the wet heat treatment process includes the following steps:

[0037] S1, turn on the nuclear magnetic resonance apparatus N1, the hot and humid airflow generating unit N2 and the host computer N3, and check whether the equipment is operating normally;

[0038] S2. According to the experimental requirements, complete the setting of relevant parameters of the temperature, relative humidity and nuclear magnetic resonance real-time non-destructive monitoring device required for the test;

[0039] S3, complete the NMR blank scan without sample loading;

[0040] S4, placing the sample chamber 2 filled with the sample to be tested in the nuclear magnetic resonance probe, and placing the nuclear magnetic resonance probe at the nuclear magnetic resonance testing position;

[0041] S5. Complete sample testing;

[0042] S6. After the test is finished, take out the sample and turn on the nuclear magnetic resonance instrument N1, the hot and humid airflow generating unit N2 and the host computer N3.

[0043] The specific steps are as follows:

[0044] Step 1: Turn on the gas circuit and instrument power switches.

[0045] Step 2: Start the nuclear magnetic resonance real-time non-destructive monitoring device, the hot and humid airflow generating unit and the start control software.

[0046] Step 3: Check whether the communication of each control module is normal. Go to the next step after all devices are communicating normally.

[0047] Step 4: According to the experimental requirements, complete the setting of relevant parameters of the temperature, relative humidity and nuclear magnetic resonance real-time non-destructive monitoring device required for the test.

[0048] Step 5: Complete a blank NMR scan without sample loading.

[0049] Step 6: Place the sample chamber filled with samples in the probe, and place the probe at the NMR test position.

[0050] Step 7: Complete sample testing.

[0051] Step 8: After the test is completed, take out the sample and turn off the nuclear magnetic resonance real-time non-destructive monitoring device, temperature and humidity generating device, etc. in turn.

[0052] The present invention adopts the sample nuclear magnetic resonance online detection technology during the wet heat treatment process to record the online monitoring of the water relaxation spectrum in the sample under the corresponding temperature and humidity conditions. The water relaxation spectrum includes but is not limited to the longitudinal relaxation time T1, the transverse relaxation time T2, and the 2D T1-T2. According to the test results of the water relaxation spectrum, the distribution of the sample water state and the migration law between each state during the wet heat treatment process are obtained.

[0053] Compared with the prior art, the utility model has the following beneficial effects:

[0054] 1. The monitoring device of the utility model includes a nuclear magnetic resonance instrument, a moist and hot airflow generating unit and a host computer. By introducing moist and hot airflow into the probe part of the nuclear magnetic resonance instrument, it can realize the online monitoring of the proton relaxation spectrum change law of the sample under specific temperature and humidity conditions during the thermal physics, thermochemistry and other processes under the premise of non-destructive sample pretreatment, thereby revealing the structure-activity relationship between the environmental conditions and the internal component migration and structural changes of the sample in each process, which is helpful to carry out the environmental condition regulation and component migration process monitoring of the sample in a specific moist and hot treatment process. The humidity and temperature of the moist and hot airflow generated by the moist and hot airflow generating unit can be controlled in real time through the host computer, so as to examine the water storage form in the sample during different moist and hot treatment processes.

[0055] 2. The nuclear magnetic resonance probe of the utility model is particularly suitable for real-time detection of samples during the wet heat treatment of samples. The bottom of the probe tube of the nuclear magnetic resonance probe of the utility model has an airflow inlet, and the airflow enters the probe tube through the airflow inlet, and then enters the sample bin in the probe tube, and contacts the sample to be tested in the sample bin. The airflow inlet has airflow temperature and humidity monitoring. The nuclear magnetic resonance probe of the utility model can collect the temperature and humidity parameters of the airflow entering the sample bin in real time through the temperature sensor and the humidity sensor, and feed the airflow temperature and humidity parameters to the control unit, so as to facilitate real-time regulation of the temperature and humidity of the airflow entering the sample bin, and ensure accurate and effective control of the test environment.

[0056] 3. The airflow inlet of the nuclear magnetic resonance instrument probe of the utility model is also provided with a heat tracing auxiliary on one side, which can provide heat to prevent the humid hot airflow from condensing after entering the sample chamber, thereby ensuring that the humid hot gas and the sample to be tested can be in full contact.

[0057] 4. The probe tube of the nuclear magnetic resonance instrument probe of the utility model also has a heat insulation tube and a heat tracing tube on the periphery. The function of the heat insulation tube is to keep the hot and humid airflow in the probe tube warm, while the function of the heat tracing tube is to provide heat. The two together ensure the temperature of the hot and humid airflow in the probe tube, thereby ensuring the temperature of the hot and humid airflow that enters the sample chamber and contacts the sample to be tested. In addition, another function of the heat insulation tube is to protect the magnet of the nuclear magnetic resonance instrument from being affected by the temperature of the hot and humid airflow in the probe tube, ensuring that the magnet of the nuclear magnetic resonance instrument is in a reliable and stable operating state.

[0058] 5. The wall and / or bottom of the sample chamber of the nuclear magnetic resonance instrument probe of the utility model are provided with openings, and the airflow entering the probe tube can enter the sample chamber through the openings, so that the sample and the external airflow can be fully contacted, and the gas-solid two-phase interaction state during the wet heat treatment process can be more truly restored. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 It is a schematic diagram of the structure of the moist hot air flow generating unit N2 of the utility model.

[0060] Figure 2 Schematic diagram of the structure of the moist hot air flow generating unit N2 in the embodiment.

[0061] Figure 3 Schematic diagram of the NMR probe structure.

[0062] Figure 4 Schematic diagram of the partial structure of the sample chamber of the nuclear magnetic resonance probe.

[0063] Figure 5 Online monitoring diagram of the moisture storage form during the online drying and moisture absorption process of plant fibers in the embodiment.

[0064] The figure marks in the accompanying drawings are: N1-nuclear magnetic resonance apparatus, N2-humid hot air flow generating unit, N3-host computer, 1-probe tube, 2-sample chamber, 3-air flow inlet, 4-insulation layer, 5-air flow inlet temperature sensor, 6-air flow inlet humidity sensor, 7-opening, 8-heating auxiliary, 9-insulation pipe, 10-heating pipe, 11-probe extension pipe, 12-sensor fixing ring, 13-water tank, 14-bubble generating device, 15-mixing chamber, 16-first heater, 17-humid hot air flow output pipeline, 18-first flow controller, 19-delivery pipeline temperature sensor, 20-sensor fixing tube, 21-relay, 22-delivery pipeline temperature controller, 23-water tank temperature sensor, 24-water tank temperature controller, 25-second heater, 26-air delivery pipeline, 27-second flow controller. DETAILED DESCRIPTION

[0065] The utility model is further described in detail below in conjunction with the embodiments.

[0066] Those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be considered to limit the scope of the present invention. If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the field or the product instructions are used. If the manufacturer of the materials or equipment used is not specified, they are all conventional products that can be purchased.

[0067] Those skilled in the art will appreciate that, unless expressly stated otherwise, the singular forms "a", "an", "said" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present utility model refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" to another element, it may be directly connected to the other element, or there may be intermediate elements. In addition, the "connection" used here may include wireless connection.

[0068] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two. The terms "inside", "upper", "lower", etc., indicating positions or state relationships, are based on the positions or state relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operate in a specific position, and therefore cannot be understood as limiting the present invention.

[0069] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "provided with" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention will be understood according to specific circumstances.

[0070] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein, including technical terms and scientific terms, have the same meaning as the general understanding of ordinary technicians in the field to which the utility model belongs. It should also be understood that those terms such as those defined in general dictionaries should be understood to have the same meaning as the meaning in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless defined as herein.

[0071] The present embodiment provides a real-time non-destructive monitoring device for the moisture state of a sample during a wet heat treatment process, which includes a nuclear magnetic resonance instrument N1, a wet heat airflow generating unit N2 and a host computer N3.

[0072] The nuclear magnetic resonance instrument N1 includes a nuclear magnetic resonance instrument probe; the nuclear magnetic resonance instrument probe includes a probe tube 1 and a sample chamber 2 located in the probe tube 1, the sample chamber 2 contains a sample to be tested, and the bottom of the probe tube 1 has an air flow inlet 3;

[0073] The humid hot airflow generating unit N2 generates humid hot airflow, which enters the probe tube 1 through the airflow inlet 3 and contacts the sample to be tested in the sample chamber 2 to perform humid heat treatment on the sample. This enables real-time non-destructive monitoring of the moisture state of the sample during the humid heat treatment process;

[0074] The host computer N3 controls the temperature and humidity of the hot and humid airflow generated by the hot and humid airflow generating unit N2.

[0075] The humid hot air flow refers to gas with a certain humidity and temperature. The humidity and temperature of the humid hot air flow are determined according to actual needs during the specific test process.

[0076] like Figure 1 As shown, the hot and humid air flow generating unit includes a water tank 13, a bubble generating device 14, a mixing chamber 15, a first heater 16 and a hot and humid air flow output pipeline 17;

[0077] The bubble generating device 14 is located at the bottom of the water tank 13, and the bubble generating device 14 is used to generate gas;

[0078] The water tank 13 contains water for generating saturated wet steam at a specific temperature;

[0079] The first heater 16 is located in the water tank 13 and is used to provide heat to the water and regulate the water temperature in the water tank 13;

[0080] The mixing chamber 15 is used to gather the humidified and heated hot and humid airflow;

[0081] The hot and humid airflow in the mixing chamber 15 is transported to the airflow inlet 3 through the hot and humid airflow output pipeline 17 .

[0082] like Figure 2 As shown, the hot and humid air flow outlet of the hot and humid air flow output pipeline 17 and the air flow inlet 3 are provided with an air flow inlet temperature sensor 5 and an air flow inlet humidity sensor 6, and the air flow inlet temperature sensor 5 and the air flow inlet humidity sensor 6 are respectively connected to the host computer N3, and the air flow inlet temperature sensor 5 and the air flow inlet humidity sensor 6 collect the temperature and humidity parameters of the hot and humid air flow entering the sample chamber 2 in real time, and feed back the temperature and humidity parameters of the hot and humid air flow to the host computer N3, and the host computer N3 controls the hot and humid air flow generating unit N2 to adjust the temperature and humidity parameters of the generated hot and humid air flow in real time.

[0083] The airflow inlet temperature sensor 5 and the airflow inlet humidity sensor 6 are fixed by a sensor fixing ring 12 and / or a sensor fixing tube 20. The fixing form of the sensor can be selected according to the actual situation.

[0084] The humid hot air flow output pipeline 17 also has a delivery pipeline temperature sensor 19 and a delivery pipeline temperature controller 22. The delivery pipeline temperature sensor 19 and the delivery pipeline temperature controller 22 are connected to the host computer N3. The delivery pipeline temperature sensor 19 collects the temperature information of the humid hot air flow output pipeline 17 in real time and transmits the collected information to the host computer N3. The host computer N3 further controls the temperature of the humid hot air flow output pipeline 17 through the delivery pipeline temperature controller 22.

[0085] The water tank 13 also has a water tank temperature sensor 23 and a water tank temperature controller 24, which are connected to the host computer N3. The water tank temperature sensor 23 collects temperature information of the water tank 13 in real time and transmits the collected information to the host computer N3. The host computer N3 further controls the temperature of the water tank 13 through the water tank temperature controller 24.

[0086] The humid hot air flow generating unit also includes a second heater 25, which is located in the air chamber and is used to heat the air in the air chamber. The heated dry hot air is transported to the air flow inlet 3 through an air delivery pipeline 26. A relay 21 is provided between the air delivery pipeline 26 and the humid hot air flow output pipeline 17. The relay 21 is connected to the host computer N3, and the host computer N3 switches the type of gas transported to the air flow inlet 3 to be humid hot air flow or dry hot air through the relay 21. That is to say, according to demand, the humid hot air flow output pipeline 17 can be opened and the air through the air delivery pipeline 26 can be closed, so as to transport humid hot air flow to the air flow inlet 3. On the contrary, the humid hot air flow output pipeline 17 can be closed and the air through the air delivery pipeline 26 can be opened, so as to transport dry hot air to the air flow inlet 3.

[0087] The air delivery pipeline 26 is provided with a second flow controller 27, and the second flow controller 27 is used to control the flow rate of the delivered hot dry air.

[0088] The humid hot air flow output pipeline 17 is provided with a first flow controller 18, and the first flow controller 18 is used to control the flow rate of the delivered humid hot air flow.

[0089] The outer side of the hot and humid air flow output pipeline 17 is provided with a heat-insulating material. The purpose of the heat-insulating material is to keep the hot and humid air flow output pipeline 17 warm and prevent the temperature of the hot and humid air flow in the hot and humid air flow output pipeline 17 from decreasing.

[0090] like Figure 3-4 As shown, the airflow inlet 3 has a heat-insulating layer 4 outside to ensure that the airflow does not lose heat when entering the probe tube 1 .

[0091] The sample chamber 2 is provided with openings 7 on the chamber wall and / or bottom, through which airflow enters the sample chamber 2 and contacts the sample to be tested in the sample chamber 2, so as to facilitate full contact between the sample and the external airflow, and more truly restore the gas-solid two-phase interaction state during the wet heat treatment process.

[0092] The opening 7 is circular in shape.

[0093] The probe tube 1 is also provided with a heat tracing aid 8 on one side close to the airflow inlet 3 , which can provide heat to prevent the humid hot airflow from condensing after entering the sample chamber 2 , thereby ensuring that the humid hot gas and the sample to be tested can fully contact each other.

[0094] The sample chamber 2 is in the shape of a cylinder.

[0095] The probe tube 1 also has an insulation tube 9 and a heat tracing tube 10 on its periphery. The insulation tube 9 is used to keep the hot and humid airflow in the probe tube 1 warm, while the heat tracing tube 10 is used to provide heat. The two tubes together ensure the temperature of the hot and humid airflow in the probe tube 1, thereby ensuring the temperature of the hot and humid airflow that enters the sample chamber 2 and contacts the sample to be tested. In addition, another function of the insulation tube 9 is to protect the magnet of the nuclear magnetic resonance instrument from being affected by the temperature of the hot and humid airflow in the probe tube, thereby ensuring that the magnet of the nuclear magnetic resonance instrument is in a reliable and stable operating state.

[0096] The nuclear magnetic resonance instrument probe further comprises a probe extension tube 11. In order to ensure that the hot and humid airflow can fully contact the sample to be tested in the sample chamber and ensure the stability of the test conditions, the length of the probe tube can be appropriately extended by the probe extension tube 11.

[0097] The NMR probe also includes: probe frame cover plate, frame plate, sample chamber cover, sample chamber connecting rod, probe frame waveguide, probe frame waveguide cover, cap, positioning block and fixing device and other common parts of the NMR probe. In addition, the NMR also includes other common parts such as magnets that generate magnetic fields in addition to the NMR probe.

[0098] The airflow output by the moist and hot airflow generating unit is communicated with the nuclear magnetic resonance instrument probe of the utility model, so as to provide reliable environmental testing conditions for the samples in the sample chamber inside the probe.

[0099] Using the monitoring device described in this embodiment, the method for real-time non-destructive monitoring of the moisture state of a sample during a wet heat treatment process includes the following steps:

[0100] S1, turn on the nuclear magnetic resonance apparatus N1, the hot and humid airflow generating unit N2 and the host computer N3, and check whether the equipment is operating normally;

[0101] S2. According to the experimental requirements, complete the setting of relevant parameters of the temperature, relative humidity and nuclear magnetic resonance real-time non-destructive monitoring device required for the test;

[0102] S3, complete the NMR blank scan without sample loading;

[0103] S4, placing the sample chamber 2 filled with the sample to be tested in the nuclear magnetic resonance probe, and placing the nuclear magnetic resonance probe at the nuclear magnetic resonance testing position;

[0104] S5. Complete sample testing;

[0105] S6. After the test is finished, take out the sample and turn on the nuclear magnetic resonance instrument N1, the hot and humid airflow generating unit N2 and the host computer N3.

[0106] The output temperature control accuracy of the moist hot air flow generating unit is ±1.0°C, and the relative humidity control accuracy is 1.5%RH.

[0107] This embodiment uses the above system to monitor the moisture state of plant fibers in the process of online drying in the process of wet heat treatment in real time and non-destructively, and the steps are as follows:

[0108] Step 1: Turn on the gas circuit and instrument power switches.

[0109] Step 2: Start the nuclear magnetic resonance detector, the hot and humid airflow generating unit and the start control software.

[0110] Step 3: Check whether the communication of each control module is normal. Go to the next step after all devices are communicating normally.

[0111] Step 4: Parameter settings of the moist hot air flow generating unit: temperature is 40°C, relative humidity is 90%.

[0112] Step 5: Parameter settings of the nuclear magnetic resonance real-time non-destructive monitoring device: proton resonance frequency 22.4MHz, receiving bandwidth 200kHz, 90° pulse time 9μs, 180° pulse time 25μs, repeated sampling waiting time 1000ms, number of echoes 2000, echo time 0.1ms, RF delay 0.025ms, analog gain 10db, digital gain 3db, repeated scanning times 32 times.

[0113] Step 6: After completing the NMR blank scan, place the sample in the probe at the NMR test position. Perform real-time T2 acquisition using the CPMG sequence, collecting spectra every 2 minutes in the first hour, and then every 5 minutes until the humidification process reaches equilibrium, that is, the T2 signal no longer increases. See the test results. Figure 5 .

[0114] Step 7: Turn off the humidified airflow, end the test, take out the sample and turn off the nuclear magnetic resonance real-time non-destructive monitoring device, temperature and humidity generating device, etc. in turn.

Claims

1. A real-time non-destructive monitoring device for the moisture state of a sample during a wet heat treatment process, characterized in that: It includes a nuclear magnetic resonance instrument (N1), a moist and hot air flow generating unit (N2) and a host computer (N3); The nuclear magnetic resonance instrument (N1) comprises a nuclear magnetic resonance instrument probe; the nuclear magnetic resonance instrument probe comprises a probe tube (1) and a sample chamber (2) located in the probe tube (1), the sample chamber (2) contains a sample to be tested, and the bottom of the probe tube (1) is provided with an air flow inlet (3); The moist hot air flow generating unit (N2) generates a moist hot air flow, and the moist hot air flow enters the probe tube (1) through the air flow inlet (3) and contacts the sample to be tested in the sample chamber (2); The host computer (N3) controls the temperature and humidity of the hot and humid airflow generated by the hot and humid airflow generating unit (N2).

2. The monitoring device according to claim 1, characterized in that: The moist hot air flow generating unit comprises a water tank (13), a bubble generating device (14), a mixing chamber (15), a first heater (16) and a moist hot air flow output pipeline (17); The bubble generating device (14) is located at the bottom of the water tank (13), and the bubble generating device (14) is used to generate gas; The water tank (13) contains water for generating saturated wet steam at a specific temperature; The first heater (16) is located in the water tank (13) and is used to provide heat to the water and regulate the temperature of the water in the water tank (13); The mixing chamber (15) is used to gather the humidified and heated hot and humid airflow; The hot and humid air flow in the mixing chamber (15) is transported to the air flow inlet (3) via the hot and humid air flow output pipeline (17).

3. The monitoring device according to claim 2, characterized in that: An air flow inlet temperature sensor (5) and an air flow inlet humidity sensor (6) are provided at the air flow inlet outlet of the air flow output pipeline (17) and the air flow inlet (3); the air flow inlet temperature sensor (5) and the air flow inlet humidity sensor (6) are respectively connected to the host computer (N3); the air flow inlet temperature sensor (5) and the air flow inlet humidity sensor (6) collect the temperature and humidity parameters of the air flow entering the sample chamber (2) in real time, and feed back the air flow temperature and humidity parameters to the host computer (N3); the host computer (N3) controls the air flow generating unit (N2) to adjust the temperature and humidity parameters of the generated air flow in real time.

4. The monitoring device according to claim 3, characterized in that: The air flow inlet temperature sensor (5) and the air flow inlet humidity sensor (6) are fixed by a sensor fixing ring (12) and / or a sensor fixing cylinder (20).

5. The monitoring device according to claim 2, characterized in that: The humid hot air flow output pipeline (17) is also provided with a delivery pipeline temperature sensor (19) and a delivery pipeline temperature controller (22). The delivery pipeline temperature sensor (19) and the delivery pipeline temperature controller (22) are connected to the host computer (N3). The delivery pipeline temperature sensor (19) collects temperature information of the humid hot air flow output pipeline (17) in real time and transmits the collected information to the host computer (N3). The host computer (N3) further controls the temperature of the humid hot air flow output pipeline (17) through the delivery pipeline temperature controller (22).

6. The monitoring device according to claim 2, characterized in that: The water tank (13) is also provided with a water tank temperature sensor (23) and a water tank temperature controller (24), the water tank temperature sensor (23) and the water tank temperature controller (24) being connected to the host computer (N3), the water tank temperature sensor (23) collecting temperature information of the water tank (13) in real time, and transmitting the collected information to the host computer (N3), and the host computer (N3) further controls the temperature of the water tank (13) through the water tank temperature controller (24).

7. The monitoring device according to claim 2, characterized in that: The humid hot air flow generating unit further comprises a second heater (25), the second heater (25) being located in the air chamber and being used for heating the air in the air chamber, the heated dry hot air being transported to the air flow inlet (3) via an air delivery pipeline (26), a relay (21) being provided between the air delivery pipeline (26) and the humid hot air flow output pipeline (17), the relay (21) being connected to the host computer (N3), the host computer (N3) switching the type of gas transported to the air flow inlet (3) to be humid hot air flow or dry hot air via the relay (21); the air delivery pipeline (26) being provided with a second flow controller (27), the second flow controller (27) being used for controlling the flow rate of the transported dry hot air.

8. The monitoring device according to claim 2, characterized in that: The humid hot air flow output pipeline (17) is provided with a first flow controller (18), and the first flow controller (18) is used to control the flow rate of the humid hot air flow being transported; The outside of the moist hot air flow output pipeline (17) is provided with heat insulation material.

9. The monitoring device according to claim 1, characterized in that: The airflow inlet (3) has a heat-insulating layer (4) on the outside; The sample chamber (2) is provided with an opening (7) on the chamber wall and / or the bottom, and airflow enters the sample chamber (2) through the opening (7) and contacts the sample to be tested in the sample chamber (2); The probe tube (1) also has a heat tracing auxiliary (8) on one side close to the airflow inlet (3); The probe tube (1) also has a heat insulation tube (9) and a heating tube (10) on its periphery; The nuclear magnetic resonance instrument probe also includes a probe extension tube (11).

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