A method for preparing vitrinite reflectance specimens of loose shale

Abstract

A method for preparing vitrinite reflectance specimens of loose shale, which relates to the technical field of shale specimen preparation; it includes the following steps: S1. Set an inclusion that wraps the shale sample outside the shale sample, and then puncture a plurality of through holes through the shale sample on the shale sample; S2. Dry the shale sample, soak it in glue in a temperature environment of 5-10°C for 2-5 hours, then evacuate it, and soak the shale sample in the glue again for 3-8 hours in a negative pressure environment to further impregnate the shale sample, and then dry and cure it; S3. Cut and polish the shale sample with the glue cured in step S2 to obtain a shale section. By setting an inclusion outside the shale sample and drilling holes in the sample at the same time in the process of evacuation and injection of glue, glue columns can be formed in the holes, which plays a role in enhancing the internal strength, and at the same time supports the strength in a three-dimensional and full-range outside the sample.

Description

Technical Field

[0001] The present invention relates to the technical field of mud shale section preparation, and specifically to a method for preparing vitrinite reflectance sections of loose mud shale. Background Art

[0002] Vitrinite reflectance can intuitively reflect the degree of thermal evolution of strata. China has a variety of shale gas reservoir types with large differences in organic matter maturity, and has strong water absorption, compactness, and low hardness. At present, the preparation samples of mud shale vitrinite reflectance mainly rely on two industry standards: the Geological and Mineral Industry Standard of the People's Republic of China (DZ / T 0275.2-2015) "Technical Specifications for Rock and Mineral Identification - Part 2: Rock Section Sampling" and the Petroleum and Natural Gas Industry Standard of the People's Republic of China (DZ / T 5913-2004) "Rock Section Preparation Method".

[0003] Due to the well-developed bedding in mud shale, high contents of various clay minerals, and loose structure, the current conventional rock section making processes such as sectioning and grinding can damage this relatively loose rock sample of shale. For example, due to physical and chemical reactions with water and clay mineral lattices, the sample will crack, turn into water, collapse, and fall off on a large scale, resulting in sample loss, especially easily causing damage to its bedding structure, and also unable to meet the requirement of the flatness of the polished sample block for section preparation, with a very low success rate of section preparation. How to successfully complete the preparation of loose samples is the basis for smoothly measuring vitrinite reflectance. To avoid the loss of geological information caused by its fragmentation, great attention should be paid to the cementation and polishing of the sample, and necessary measures should be taken to improve the defects of the current mud shale polished section preparation technology.

[0004] For sample blocks (samples drilled at the well site) or cuttings (fragments collected at the well site) that are loose, soft, and have insufficient mechanical strength, in the prior art, they are generally broken, and after being broken, they are subjected to glue curing treatment. After the glue is made, the sample will continue to disperse and dissolve in water during the grinding and polishing process, and the section preparation cannot be completed.

[0005] For sample blocks with a certain strength or the traditional method of boiling with hot glue, this process is prone to the appearance of glue interlayers, and there is no glue penetration in the central area of the clay block. There is no cementing effect in the central part of the sample block (there is no sealing and waterproofing effect produced by the complete penetration and uniform cementation of glue and the sample), and there is no effect of promoting its mechanical strength by curing (grinding and polishing sample slices require a certain hardness. It can be understood by using the Mohs hardness. The sand disk and the sample block rub against each other to achieve a fine polishing effect, and a certain pressure needs to be applied. Many loose samples are directly ground and polished without the corresponding hardness support, so the sample needs to be modified). After the sample block is made, when cutting with a tool to determine the grinding and polishing plane, the part without glue will directly disperse and dissolve in water, and the sample slice preparation fails.

[0006] If the loose sample is perforated and then vacuum-impregnated with glue alone (to improve the impregnation efficiency and effect), practice has proved that it is also very easy for the sample to not withstand mechanical oscillation or pressure, resulting in cracking or fragmentation (the mechanical strength of the initial shale sample is very poor). Summary of the Invention

[0007] The object of the present invention is to provide a method for preparing vitrinite reflectance slices of loose shale, which can effectively solve the problems in the background technology.

[0008] The technical solution to achieve the above object is: a method for preparing vitrinite reflectance slices of loose shale for preparing slices of massive shale, characterized by including the following steps:

[0009] S1. Set an inclusion that wraps the shale sample outside the shale sample, and then puncture a plurality of through holes that penetrate the shale sample on the shale sample;

[0010] S2. Dry the shale sample, soak it in glue in a temperature environment of 5-10°C for 2-5 hours, then evacuate, and soak the shale sample in the glue again for 3-8 hours under a negative pressure environment to make the glue further penetrate the shale sample, and then dry and cure it;

[0011] S3. Cut and polish the shale sample with the glue cured in step S2 to obtain a shale slice.

[0012] Further, the through holes in step S1 are evenly distributed on the largest side of the shale sample and do not cross each other. The diameter of the through holes is 0.3-0.6 mm, and the distance between adjacent through holes is not less than 0.5-3 cm.

[0013] Further, the inclusion is made of 3D printing resin material and is wound around the shale sample by a 3D printing device.

[0014] Further, the glue is epoxy resin glue.

[0015] Further, in step S1, an inclusion structure and a perforating device are used to set an inclusion outside the shale sample and puncture a plurality of through holes.

[0016] Further, the inclusion structure and the perforating device include a housing, a sample positioning and rotation driving mechanism is arranged in the housing, an inclusion structure mechanism is arranged above the sample positioning and rotation driving mechanism, and a sample punching mechanism is arranged below the sample positioning mechanism.

[0017] Further, the sample positioning and rotation driving mechanism includes a rotating rod and a movable rod located on the same horizontal straight line. The shale sample is clamped between the rotating rod and the movable rod. U-shaped pins are arranged at the relative ends of the rotating rod and the movable rod and inserted into the shale sample along both ends.

[0018] The rotating rod is rotatably installed in the shell through a bearing. One end of the movable rod far from the rotating rod is connected with a driving motor for driving the movable rod to rotate. A linear cylinder is installed in the shell below the driving motor through a support. The driving motor is installed on the linear cylinder through a connecting plate. The linear cylinder is used to drive the movable rod in transmission connection with the driving motor to move forward and cooperate with the rotating rod to clamp the sample.

[0019] Further, the inclusion structure mechanism includes a first left-right displacement driving module arranged above the rotating rod and the movable rod. A connecting seat that can displace left and right along the first left-right displacement driving module is connected to the first left-right displacement driving module. A lifting driver with a telescopic end facing down is installed on the connecting seat. The telescopic end of the lifting driver is installed with a printing nozzle through a mounting seat.

[0020] Further, the sample punching mechanism includes a second left-right displacement driving module installed at the bottom of the shell. A front-back displacement module is installed on the slider of the second left-right displacement driving module. A lifting driver is installed on the slider of the front-back displacement module. The telescopic end of the lifting driver is arranged upward and connected with a punching needle located directly below the sample positioned by the sample positioning mechanism.

[0021] Further, in step S2, a sample dipping and drying device is used to soak and dry the shale sample with glue. The sample dipping and drying device includes a vacuum container, a vacuum pumping device, and a glue storage tank. The vacuum container includes a container body with an open upper end and a sealing cover hermetically connected to the container body. A support is arranged in the vacuum container, and a temperature-controlled heating plate is supported on the support. A silica gel cup for placing the sample is arranged above the temperature-controlled heating plate.

[0022] A filter screen for supporting and placing the sample is arranged in the silica gel cup. Lifting drivers are arranged on both sides in the silica gel cup. The tail ends of the lifting drivers are connected to the cup wall of the silica gel cup through connecting blocks. The telescopic ends of the lifting drivers are vertically downward and connected to the filter screen.

[0023] A hot air blower is arranged above the silica gel cup and installed in the vacuum container with the hot air outlet facing downward towards the cup mouth of the silica gel cup.

[0024] Advantages of the present invention:

[0025] The present invention first sets inclusion bodies outside the shale sample to seal and fix the loose sample. The inclusion bodies are polymer materials used in the field of 3D printing, which are highly plastic, environmentally friendly and safe materials commonly used at present. For the loose clay block sample of shale, it is very suitable and can reduce or even avoid the occurrence of fragmentation of the shale sample during the preparation process.

[0026] Since shale is a rock formed by the dehydration and cementation of clay and mainly consists of clay minerals (such as kaolinite and hydromica), it is a porous medium with obvious thin bedding structures and is extremely prone to spontaneous imbibition, simply referred to as the imbibition principle. Therefore, the present invention first immerses it in glue at a temperature environment of 5-10°C for 2-5 hours, so that the porous medium spontaneously sucks in part of the glue under the drive of capillary force. Then, under the action of negative pressure, the air in the capillary is pumped out to ensure that the glue fully penetrates the shale sample.

[0027] The inclusion body is heated and softened outside the sample and closely wraps around the shaped object. Because it can quickly dry and harden, it is integrally wrapped to form an inclusion body. According to the material characteristics, the inclusion body also has a certain amount of stretching elasticity. It is the same polymer resin glue as the glue used in the imbibition treatment by soaking. The material characteristics are relatively similar. By combining these two materials, the process means of using epoxy resin glue to bond mineral samples in the petroleum geology direction, namely, the glue wire mesh shell + liquid impregnated glue bonding, is actively explored and expanded.

[0028] The inclusion body can control the density of the wrapping wire mesh according to the size of the shale sample to enhance the wrapping force. During the imbibition + vacuum pumping process, the vacuum pumping has a certain strengthening imbibition effect on the glue in cooperation with the mesh holes of the inclusion body. After drying, the mesh holes of the inclusion body are adhered to the glue together to form an integral support framework, thus effectively improving the mechanical strength of the shale sample.

[0029] The present invention also drills holes in the sample. Even if cracking or fragmentation occurs during drilling, it is within the comprehensive three-dimensional inclusion body.

[0030] Loose samples are mostly composed of muddy powder texture, which is caused by poor geological diagenesis, cementation and compaction. The purpose of drilling holes in the wrapped rock sample is to promote the further penetration of the glue during the soaking process of the epoxy resin glue. Use a needle to drill holes with a needle punching device, and holes that penetrate the rock sample can be drilled to minimize the impact of mechanical vibration on cracking and fragmentation.

[0031] The present invention simultaneously punches holes in the sample. During the process of evacuating and injecting glue, glue columns can be formed in the holes, which play a role in enhancing the internal strength. At the same time, the strength is supported in the three-dimensional full range outside the sample. Since it becomes an integral part with the sample block after the glue injection and drying, the hardness of the sample block is greatly improved. If the traditional glue-boiling method is used, in practice, it has repeatedly occurred that the sample is quickly cut due to insufficient strength and disintegrates when encountering water. Among them, there is also the phenomenon of disintegration caused by the insufficient infiltration of the glue and the rapid action of a large amount of clay in the shale when encountering water.

[0032] The sample block is solidified and formed by alternately treating it with hot and cold epoxy resin, so that the glue is evenly distributed inside the sample block, increasing the strength. Brief Description of the Drawings

[0033] Figure 1 It is a schematic structural diagram of the inclusion structure and perforating equipment of the shale sample;

[0034] Figure 2 It is a structural diagram of the sample impregnating and drying system;

[0035] Figure 3 It is a schematic diagram of the inclusion with a mesh structure set for the shale sample;

[0036] Figure 4 It is an observation photo of the section prepared in Application Example 1 in Example 1 under the microscope;

[0037] Figure 5 It is an observation photo of the section prepared by the existing process under the microscope. Detailed Embodiment Example 1

[0038] The present invention provides a method for preparing a vitrinite reflectance section of loose shale, and the specific steps are as follows:

[0039] S1. A wrapper that wraps the shale sample is set outside the shale sample. Then, a plurality of through holes that penetrate the shale sample are punctured on the shale sample. The through holes are evenly distributed on the largest side of the shale sample and do not cross each other. The diameter of the through holes is 0.3 - 0.6 mm, and the distance between adjacent through holes is 0.5 - 3 cm;

[0040] S2. The shale sample is dried and immersed in glue at a temperature of 5 - 10 °C for 2 - 5 hours. Then, it is evacuated, and the shale sample is immersed in the glue again for 3 - 8 hours under a negative pressure environment to make the glue further penetrate the shale sample. Then, it is dried and cured;

[0041] S3. The shale sample with the glue cured in step S2 is cut and polished to obtain a shale section.

[0042] In step S1, the inclusion is made of 3D printing resin material, and the inclusion is constructed outside the shale sample by a 3D printing pen. The inclusion 2 can be Figure 3 As shown in FIG. , the shale sample 1 is wound from one end to the other end.

[0043] As a further explanation of this embodiment, the glue is epoxy resin glue produced by Buehler Corporation of the United States, and the specific models are 20-3430-064 and 20-3432-016. When using, 20-3430-064 and 20-3432-016 can be directly mixed according to the proportion.

[0044] The application example of Example 1 is the preparation of shale slices, and the specific steps are as follows:

[0045] S1. Take a block of shale sample, and set an inclusion that wraps the shale sample outside the shale sample. The inclusion is wrapped from one end of the shale sample 1 to the other end. Then, through holes are punctured on the shale sample. The through holes are evenly distributed on the largest side of the shale sample and do not cross each other. The diameter of the through holes is 0.3 mm, and the spacing between adjacent through holes is 0.5 cm.

[0046] S2, drying the shale sample, and soaking it in glue at a temperature of 5-10°C for 3 hours, then evacuating the shale sample, and soaking the shale sample in glue again for 6 hours under negative pressure to allow the glue to further penetrate the shale sample, and then drying and solidifying it;

[0047] S3. Cutting and grinding the mudstone sample after the glue solidifies in step S2 to obtain mudstone slices.

[0048] Figure 4 This is a photo of the shale slice prepared in the application example observed under a microscope. It can be seen from the figure that the polished surface of the slice prepared according to this embodiment has no stains, no needle scratches, no cloth texture, the boundaries between the components are clear, and there are no scratches and pitting.

[0049] Figure 5 This is a photo of a shale slice prepared by the existing process observed under a microscope. It can be seen from the figure that the polished surface of the slice has secondary cracks caused by loose and poorly sealed samples during the grinding process, coarse scratches caused by poor grinding effect, and fine scratches caused by poor grinding effect. Coarse and fine scratches often coexist, which greatly increases the difficulty of the process and greatly reduces the production efficiency. Example 2

[0050] The difference between this embodiment and embodiment 1 is that: in step S1 of embodiment 1, inclusion structures and perforating equipment are used to set inclusions outside the shale sample and puncture multiple through holes, such as Figure 1As shown, the inclusion structure and perforation device includes a shell 1, a sample positioning and rotation drive mechanism 2 is arranged in the shell 1, an inclusion structure mechanism 3 is arranged above the sample positioning and rotation drive mechanism 2, and a sample perforation mechanism 4 is arranged below the sample positioning and rotation drive mechanism 2.

[0051] The sample positioning and rotation driving mechanism 2 comprises a rotating rod 2.1 and a movable rod 2.2 arranged in the same horizontal straight line. The shale sample is clamped between the rotating rod 2.1 and the movable rod 2.2. The opposite ends of the rotating rod 2.1 and the movable rod 2.2 are provided with U-shaped pins 2.5 inserted into the shale sample along both ends.

[0052] The rotating rod 2.1 is rotatably installed in the shell 1 through a bearing, and the end of the movable rod 2.2 away from the rotating rod 2.1 is connected to a driving motor 2.3 for driving the movable rod 2.2 to rotate, and a linear cylinder 2.4 is installed in the shell 1 below the driving motor 2.3 through a support. The driving motor 2.3 is installed on the linear cylinder 2.4 through a connecting plate. The linear cylinder 2.4 is used to drive the movable rod 2.2, which is transmission-connected to the driving motor 2.3, forward to cooperate with the rotating rod 2.1 to clamp the sample.

[0053] The inclusion structure mechanism 3 includes a first left-right displacement driving module 3.1 arranged above the rotating rod 2.1 and the movable rod 2.2. The first left-right displacement driving module 3.1 is connected to a connecting seat 3.2 that can be displaced left-right along the first left-right displacement driving module 31. A lifting driver 3.3 with a telescopic end facing downward is installed on the connecting seat 3.2. The lifting driver 3.3 can be but is not limited to using commonly used linear driving mechanisms such as cylinders, hydraulic cylinders, and electric cylinders. The telescopic end of the lifting driver 3.3 is installed with a printing nozzle 3.5 through a mounting seat 3.4, and the printing nozzle 3.5 is correspondingly connected to a 3D printer host.

[0054] The sample punching mechanism 4 includes a second left-right displacement driving module 4.1 installed at the bottom of the shell 1, and a front-back displacement module 4.4 that can be displaced left-right along the second left-right displacement driving module 4.1 is installed on the second left-right displacement driving module 4.1. A lifting driver 4.2 is installed on the front-back displacement module 4.4, and the telescopic end of the lifting driver 4.2 is arranged upward and connected to a punching needle 4.3 located directly below the sample positioned by the sample positioning mechanism 2.

[0055] Inclusion structure and working process of perforating equipment:

[0056] 1) Place the shale sample between the rotating rod 2.1 and the movable rod 2.2. The linear cylinder 2.4 drives the movable rod 2.2 connected to the driving motor 2.3 forward, so that the U-shaped pins 2.5 at the opposite ends of the rotating rod 2.1 and the movable rod 2.2 are positioned and inserted at both ends of the sample to achieve sample positioning.

[0057] 2) The first left - right displacement driving module 31 and the lifting driver 3.3 cooperate to drive the printing nozzle 3.5 to move to the leftmost or rightmost end of the sample.

[0058] 3) Control the printing nozzle 3.5 to extrude wire. At the same time, the driving motor 2.3 cooperates to drive the sample to rotate, the lifting driver 3.3 drives the printing nozzle 3.5 to lift, and the first left - right displacement driving module 31 drives the printing nozzle 3.5 to horizontally displace, so as to wind the wrapping body from one end to the other end on the surface of the sample.

[0059] 4) After the construction of the wrapping body is completed, the driving motor 2.3 drives the side with the largest side of the sample to face downwards, and the lifting driver 4.2 drives the punching needle 4.3 to pierce through - holes upwards on the shale sample. At the same time, the second left - right displacement driving module 4.1 and the front - back displacement module 4.4 cooperate to drive the punching needle 4.3 to displace in the left - right and front - back directions, so as to perforate the shale sample. Example 3

[0060] The differences between Example 3 and Example 1 and Example 2 are as follows:

[0061] As Figure 2 shown, in step S2, a sample dipping and drying device 5 is used to soak and dry the shale sample with glue. The sample dipping and drying device 5 includes a vacuum - pumping container 5.1, a vacuum - pumping device 5.2, and a glue storage tank 5.3. The vacuum - pumping container 5.1 includes a container body 5.11 and a sealing cover 5.12 sealed and connected to the container body 5.11. A support 5.4 is arranged inside the vacuum - pumping container 5.1. A temperature - controlled heating plate 5.5 is installed at the bottom of the support 5.4. Above the temperature - controlled heating plate 5.5, a silica gel cup 5.6 for placing the sample is arranged. Above the silica gel cup 5.6, a drying device 5.14 is arranged. The drying device 5.14 uses a hot - air blower with the hot - air outlet facing downwards towards the mouth of the silica gel cup.

[0062] The vacuum - pumping device 5.2 is connected to the vacuum - pumping container 5.1. The glue storage tank 5.3 is connected to the silica gel cup 5.6 through a delivery pump 5.8 and a delivery pipeline 5.9. The delivery pipeline 5.9 is hermetically connected to the vacuum - pumping container 5.1.

[0063] A filter screen 5.13 for supporting and placing the sample is arranged inside the silica gel cup 5.6. Lifting drivers 5.10 are arranged on both sides inside the silica gel cup 5.6. The lifting drivers 5.10 can but are not limited to use lifting driving mechanisms such as electric cylinders and hydraulic cylinders. The tail ends of the lifting drivers 5.10 are connected to the cup wall of the silica gel cup 5.6 through connection blocks. The telescopic ends of the lifting drivers 5.10 are vertically downward and connected to the filter screen 5.13.

[0064] The working process of the sample dipping and drying device 5:

[0065] 1) Place the shale sample with the inclusion structure and the sample processed by the perforation equipment on the filter screen 5.13 in the silica gel cup 5.6, and the lifting drive 5.10 drives the filter screen 5.13 to the low position;

[0066] 2) Dry the shale sample with the through-holes punctured by the drying device 5.14;

[0067] 3) The transfer pump 5.8 transfers the glue in the glue storage tank 5.3 to the silica gel cup 5.6 and submerges the sample. The temperature control device 5.5 controls the temperature in the silica gel cup 5.6 at 5 - 10 °C, and then the sample is soaked in the glue at a temperature of 5 - 10 °C for 2 - 5 hours.

[0068] 4) The temperature control device 5.5 controls the temperature in the silica gel cup 5.6 to remain at 5 - 10 °C, and at the same time, the vacuum pumping device 5.2 pumps vacuum to make the pressure in the vacuum pumping container 5.1 reach -0.1 MP, so that the sample is soaked in the glue in the silica gel cup 5.6 under negative pressure for 3 - 8 hours to allow the glue to penetrate the shale sample;

[0069] 5) The lifting drive 5.10 drives the sample on the filter screen 5.13 upward above the glue liquid level, and then dries the sample through the drying device 5.14 to cure the glue in the sample.

Claims

1. A method for preparing slices of loose shale vitrinite reflectance, which is used for preparing slices of massive shale. It is characterized in that The steps include: S1. Arranging an inclusion outside the shale sample to enclose the shale sample, and then piercing a plurality of through holes penetrating the shale sample; S2, drying the shale sample, and soaking it in glue at a temperature of 5-10°C for 2-5 hours, then evacuating the shale sample, and soaking the shale sample in glue again for 3-8 hours under negative pressure to allow the glue to further penetrate the shale sample, and then drying and solidifying it; S3. Cutting and grinding the mudstone sample after the glue solidifies in step S2 to obtain mudstone slices.

2. The method for preparing the vitrinite reflectance of loose shale according to claim 1, Features: The through holes in step S1 are evenly distributed on the largest side of the shale sample and do not cross each other. The diameter of the through holes is 0.3-0.6 mm, and the spacing between adjacent through holes is 0.5-3 cm.

3. The method for preparing the vitrinite reflectance of loose shale according to claim 1, Features: The inclusion is made of 3D printing resin material and is wound around the shale sample through 3D printing equipment.

4. The method for preparing the vitrinite reflectance of loose shale according to claim 1, Features: The glue is epoxy resin glue.

5. The method for preparing the vitrinite reflectance of loose shale according to claim 1, Features: In step S1, inclusion structures and perforating equipment are used to set inclusions outside the shale sample and puncture multiple through holes.

6. A method for preparing a vitrinite reflectance slice of loose shale according to claim 5, Features: The inclusion structure and perforation device comprises a shell, in which a sample positioning and rotation driving mechanism is arranged, an inclusion structure mechanism is arranged above the sample positioning and rotation driving mechanism, and a sample perforation mechanism is arranged below the sample positioning mechanism.

7. A method for preparing a vitrinite reflectance slice of loose shale according to claim 6, Features: The sample positioning and rotation driving mechanism comprises a rotating rod and a movable rod located on the same horizontal line, the shale sample is clamped between the rotating rod and the movable rod, and the opposite ends of the rotating rod and the movable rod are provided with U-shaped pins inserted into the shale sample along both ends; The rotating rod is rotatably installed in the shell through a bearing, and the end of the movable rod away from the rotating rod is connected to a driving motor for driving the movable rod to rotate. A linear cylinder is installed in the shell below the driving motor through a support. The driving motor is installed on the linear cylinder through a connecting plate. The linear cylinder is used to drive the movable rod transmission connected to the driving motor forward to cooperate with the rotating rod to clamp the sample.

8. The method for preparing the vitrinite reflectance of loose shale according to claim 6, Features: The inclusion structure mechanism includes a first left - right displacement driving module arranged above the rotating rod and the movable rod. A connecting seat that can be displaced left and right along the first left - right displacement driving module is connected to the first left - right displacement driving module. A lifting driver with a telescopic end facing downwards is installed on the connecting seat, and a printing nozzle is installed on the telescopic end of the lifting driver through a mounting seat.

9. A method for preparing vitrinite reflectance specimens of loose shale, according to claim 6, characterized in that: The sample punching mechanism includes a second left - right displacement driving module installed at the bottom of the housing. A front - rear displacement module is installed on the slider of the second left - right displacement driving module. A lifting driver is installed on the slider of the front - rear displacement module. The telescopic end of the lifting driver is arranged upwards and is connected to a punching needle located directly below the sample positioned by the sample positioning mechanism.

10. A method for preparing vitrinite reflectance specimens of loose shale, according to claim 1, characterized in that: In step S2, a sample dipping and drying device for glue is used to soak and dry the shale sample. The sample dipping and drying device includes a vacuum container, a vacuum pumping device, and a glue storage tank. The vacuum container includes a container body with an open upper end and a sealing cover hermetically connected to the container body. A support is arranged inside the vacuum container, and a temperature - controlled heating plate is supported on the support. A silica gel cup for placing the sample is arranged above the temperature - controlled heating plate; A filter screen for supporting and placing the sample is arranged inside the silica gel cup. Lifting drivers are arranged on both sides inside the silica gel cup. The tail end of the lifting driver is connected to the cup wall of the silica gel cup through a connecting block. The telescopic end of the lifting driver is vertically downward and is connected to the filter screen; Above the silica gel cup, a hot air blower is installed inside the vacuum container and the hot air outlet faces downwards towards the cup mouth of the silica gel cup.

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