Leather vacuum drying machine with safe explosion-proof function

Abstract

The invention relates to the technical field of leather vacuum dryers, and discloses a leather vacuum dryer with a safe explosion-proof function, the leather vacuum dryer comprises a vacuum dryer body and a condensing device, the condensing device comprises a bottom plate, the upper surface of the bottom plate is fixedly connected with a mounting rack, and the middle part of the inner surface of the mounting rack is fixedly connected with a buffer tank; a rotary-vane vacuum pump is fixedly connected to the outer surface of the side, close to the vacuum dryer body, of the mounting frame, an air inlet of the rotary-vane vacuum pump is communicated with a drying cavity of the vacuum dryer body through a connecting pipe, an air outlet of the rotary-vane vacuum pump is communicated with a buffer tank, and an air outlet of the buffer tank is communicated with a roots vacuum pump through a vacuum pipeline. A gas outlet of the roots vacuum pump is communicated with a condenser through a pipeline, and a liquid outlet of the condenser is communicated with a closed recovery tank through a pipeline; through cooperation of the structures, the vacuum stability of the vacuum dryer body can be maintained, meanwhile, leakage of liquefied organic solvent is avoided, explosion is prevented, and safety is improved.

Description

Technical Field

[0001] This invention belongs to the technical field of leather vacuum drying machines, specifically a leather vacuum drying machine with safety and explosion-proof functions. Background Technology

[0002] During the vacuum drying process of leather, the liquefied liquid typically contains a mixture of organic solvents, such as ethanol, acetone, and water. This is because organic solvent-based chemicals are widely used in leather processing stages, such as finishing and tanning. These solvents evaporate during drying and are captured and liquefied by the condensation system.

[0003] During the vacuum drying process of leather, organic solvents such as ethanol and acetone often remain on the surface of the leather. These solvents have significantly lower boiling points under vacuum conditions and are easily vaporized to form flammable gas mixtures.

[0004] The existing technology has the following key problems: 1. Significant explosion risk: The lower explosion limit is low when solvent vapor mixes with air, and traditional dryers lack a sealed design for the condensation recovery system, which can easily lead to vapor leakage.

[0005] 2. Conventional single-stage vacuum pumps are difficult to operate at the same pace as rapid air extraction, which affects drying efficiency and deep vacuum, resulting in high solvent residue and increased risks in subsequent processing.

[0006] 3. Lack of inerting protection: Most equipment is not equipped with oxygen concentration monitoring and inert gas injection systems, which cannot dynamically suppress the formation of flammable atmosphere.

[0007] Therefore, we propose a leather vacuum dryer with safety and explosion-proof functions. Summary of the Invention

[0008] The purpose of this invention is to provide a leather vacuum dryer with explosion-proof function in order to maintain the vacuum stability of the vacuum dryer body, prevent the leakage of liquefied organic solvents, prevent explosions, and improve safety.

[0009] The technical solution adopted in this invention is as follows: A leather vacuum dryer with explosion-proof safety features includes a vacuum dryer body and a condensing device. The condensing device includes a base plate, a mounting frame fixedly connected to the upper surface of the base plate, a buffer tank fixedly connected to the center of the inner surface of the mounting frame, and a rotary vane vacuum pump fixedly connected to the outer surface of the mounting frame near the vacuum dryer body. The inlet of the rotary vane vacuum pump is connected to the drying chamber of the vacuum dryer body via a connecting pipe, and the outlet of the rotary vane vacuum pump is connected to the buffer tank. The outlet of the buffer tank is connected to a Roots vacuum pump via a vacuum pipe, and the outlet of the Roots vacuum pump is connected to a condenser via a pipe. The liquid outlet of the condenser is connected to a closed recovery tank via a pipe.

[0010] In a preferred embodiment of the invention, the closed recycling tank is fixedly installed in the middle of the upper surface of the base plate.

[0011] In a preferred embodiment of the invention, a nitrogen cylinder is mounted on the lower end of the side of the mounting bracket away from the condenser, and the nitrogen pipe of the nitrogen cylinder is connected to the exhaust port of the condenser via a three-way valve.

[0012] In a preferred embodiment of the invention, the number of nitrogen cylinders is several, and the several nitrogen cylinders are arranged equidistantly on the outer side of the mounting frame.

[0013] In a preferred embodiment of the invention, the input terminals of the Roots vacuum pump and the rotary vane vacuum pump are electrically connected to an external power source.

[0014] In a preferred embodiment of the invention, a cabinet door is installed on the left side of the vacuum dryer body.

[0015] In a preferred embodiment of the invention, a controller is mounted on the upper front side of the vacuum dryer body, and the output of the controller is electrically connected to the Roots vacuum pump and the rotary vane vacuum pump.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. In this invention, during leather drying, a rotary vane vacuum pump is used to quickly extract air and water vapor from the drying chamber initially, establishing a basic vacuum environment to create conditions for subsequent high vacuum. The rotary vane vacuum pump is connected to the inlet of a buffer tank via a vacuum pipeline, where the pre-compressed gas is temporarily stored. Simultaneously, a Roots vacuum pump is connected in series with the outlet of the buffer tank to extract the pre-compressed gas and connects to the condenser inlet. When the vacuum level drops below 1 kPa, the Roots vacuum pump automatically starts, raising the vacuum level to 10 mbar, accelerating the movement of water vapor into the condenser. The pressurized vapor is then directionally transported to the condenser for liquefaction. The liquefied organic solvent can flow into a closed recovery tank through a bottom pipeline, preventing leakage and potential explosion. This combination of structures maintains the vacuum stability of the vacuum dryer while preventing leakage of liquefied organic solvent, thus preventing explosions and improving safety.

[0017] 2. In this invention, the exhaust port of the condenser is connected to a nitrogen pipeline in parallel through a three-way valve. When the oxygen concentration is detected to be high, nitrogen can be injected into the condenser through a nitrogen cylinder for purging to prevent it from accumulating in the vacuum chamber and forming a flammable atmosphere, thereby reducing the risk of combustion and explosion. Attached Figure Description

[0018] Figure 1 This is a perspective view of the present invention; Figure 2 This is a rear view of the condensation device in this invention; Figure 3 This is a front view of the condensation device in this invention; Figure 4 This is a top view of the condensation device in this invention.

[0019] Explanation of reference numerals in the attached drawings: 1-Vacuum dryer body; 2-Condensing device; 11-Cabinet door; 12-Controller; 21-Base plate; 22-Mounting bracket; 23-Buffer tank; 24-Connecting pipe; 25-Roots vacuum pump; 26-Closed recovery tank; 27-Nitrogen cylinder; 28-Rotary vane vacuum pump; 29-Condenser. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] The following will combine Figures 1-4A detailed description is provided of a leather vacuum dryer with explosion-proof safety features according to an embodiment of the present invention. Example 1

[0022] Reference Figures 1-4 A leather vacuum dryer with explosion-proof safety features includes a vacuum dryer body 1 and a condensing device 2. The condensing device 2 includes a base plate 21, a mounting bracket 22 fixedly connected to the upper surface of the base plate 21, a buffer tank 23 fixedly connected to the middle of the inner surface of the mounting bracket 22, and a rotary vane vacuum pump 28 fixedly connected to the outer surface of the mounting bracket 22 near the vacuum dryer body 1. The air inlet of the rotary vane vacuum pump 28 is connected to the drying chamber of the vacuum dryer body 1 through a connecting pipe 24, and the air outlet of the rotary vane vacuum pump 28 is connected to the buffer tank 23. The air outlet of the buffer tank 23 is connected to a Roots vacuum pump 23 through a vacuum pipe. 5. The outlet of the Roots vacuum pump 25 is connected to the condenser 29 via a pipe, and the outlet of the condenser 29 is connected to the closed recovery tank 26 via a pipe. Specifically, during leather drying, the rotary vane vacuum pump 28 is used to quickly extract air and water vapor from the drying chamber initially, establishing a basic vacuum environment to create conditions for subsequent high vacuum. The rotary vane vacuum pump 28 is connected to the inlet of the buffer tank 23 via a vacuum pipe, and the pre-compressed gas is temporarily stored in the buffer tank 23. At the same time, the Roots vacuum pump 25 is connected in series with the outlet of the buffer tank 23 to extract the pre-compressed gas in the buffer tank 23 and connects to the inlet of the condenser 29. When the vacuum degree reaches 1 kPa... The Roots vacuum pump 25 will automatically start, raising the vacuum level to 10 mbar, accelerating the movement of water vapor into the condenser 29. The pressurized vapor is then directed to the condenser 29 for liquefaction. The liquefied organic solvent can flow into the closed recovery tank 26 through the bottom pipe, preventing leakage and potential explosion. The combination of the above structures can maintain the vacuum stability of the vacuum dryer body 1 while preventing leakage of liquefied organic solvent, thus preventing explosion and improving safety. Example 2

[0023] Reference Figures 1-4 A closed recovery tank 26 is fixedly installed in the middle of the upper surface of the base plate 21. A nitrogen cylinder 27 is installed at the lower end of the side of the mounting bracket 22 away from the condenser 29. The nitrogen pipeline of the nitrogen cylinder 27 is connected to the exhaust port of the condenser 29 through a three-way valve. There are several nitrogen cylinders 27, and the several nitrogen cylinders 27 are equidistantly arranged on the outer side of the mounting bracket 22. Specifically, the exhaust port of the condenser 29 is connected to a nitrogen pipeline in parallel through a three-way valve. When the oxygen concentration is detected to be high, nitrogen can be injected into the condenser 29 through the nitrogen cylinder 27 for purging to prevent it from accumulating in the vacuum chamber and forming a flammable atmosphere, thereby reducing the risk of combustion and explosion.

[0024] Reference Figures 1-4The input terminals of the Roots vacuum pump 25 and the rotary vane vacuum pump 28 are electrically connected to an external power supply. A cabinet door 11 is installed on the left side of the vacuum dryer body 1, and a controller 12 is installed on the upper front side of the vacuum dryer body 1. The output terminal of the controller 12 is electrically connected to the Roots vacuum pump 25 and the rotary vane vacuum pump 28. Specifically, the controller 12 uses a single-chip microcomputer as the main control chip, and its model is STC89C51. After opening the cabinet door 11, the leather that needs to be dried can be placed inside the vacuum dryer body 1 for drying.

[0025] The implementation principle of the leather vacuum dryer with explosion-proof safety function in this application is as follows: When using this device, first connect an external power source. Place the leather to be dried inside the vacuum dryer body 1. A rotary vane vacuum pump 28 initially and rapidly extracts air and water vapor from the drying chamber to establish a basic vacuum environment, creating conditions for subsequent high vacuum. The rotary vane vacuum pump 28 is connected to the inlet of the buffer tank 23 via a vacuum pipe, temporarily storing the pre-compressed gas in the buffer tank 23. Simultaneously, a Roots vacuum pump 25 is connected in series with the outlet of the buffer tank 23 to extract the pre-compressed gas and connects to the inlet of the condenser 29. When the vacuum level drops below 1 kPa, the Roots vacuum pump 25 automatically starts, raising the vacuum level to 10 mbar, accelerating the movement of water vapor into the condenser 29. The pressurized vapor is then directionally transported to the condenser 29 for liquefaction. The liquefied organic solvent can flow into the closed recovery tank 26 through the bottom pipe, preventing leakage and potential explosion. This combination of structures maintains the vacuum stability of the vacuum dryer body 1 while preventing leakage of liquefied organic solvent, thus preventing explosions and improving safety.

[0026] On the other hand, the exhaust port of the condenser 29 is connected to a nitrogen pipeline in parallel through a three-way valve. When the oxygen concentration is detected to be high, nitrogen can be injected into the condenser 29 through the nitrogen cylinder 27 to purge it, preventing it from accumulating in the vacuum chamber and forming a flammable atmosphere, thereby reducing the risk of combustion and explosion.

[0027] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0028] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A leather vacuum dryer with explosion-proof safety function, comprising a vacuum dryer body (1) and a condensation device (2), characterized in that: The condensing device (2) includes a base plate (21), a mounting bracket (22) is fixedly connected to the upper surface of the base plate (21), a buffer tank (23) is fixedly connected to the middle of the inner surface of the mounting bracket (22), a rotary vane vacuum pump (28) is fixedly connected to the outer surface of the mounting bracket (22) near the vacuum dryer body (1), the air inlet of the rotary vane vacuum pump (28) is connected to the drying chamber of the vacuum dryer body (1) through a connecting pipe (24), the air outlet of the rotary vane vacuum pump (28) is connected to the buffer tank (23), the air outlet of the buffer tank (23) is connected to a Roots vacuum pump (25) through a vacuum pipe, the air outlet of the Roots vacuum pump (25) is connected to a condenser (29) through a pipe, and the liquid outlet of the condenser (29) is connected to a closed recovery tank (26) through a pipe.

2. A leather vacuum dryer with explosion-proof safety function according to claim 1, characterized in that: The closed recycling tank (26) is fixedly installed in the middle of the upper surface of the base plate (21).

3. A leather vacuum dryer with explosion-proof safety function according to claim 1, characterized in that: A nitrogen cylinder (27) is installed on the lower end of the side of the mounting bracket (22) away from the condenser (29). The nitrogen pipe of the nitrogen cylinder (27) is connected to the exhaust port of the condenser (29) through a three-way valve.

4. A leather vacuum dryer with explosion-proof safety function according to claim 3, characterized in that: The number of nitrogen cylinders (27) is several, and the several nitrogen cylinders (27) are arranged at equal intervals on the outer side of the mounting frame (22).

5. A leather vacuum dryer with explosion-proof safety function according to claim 1, characterized in that: The input terminals of the Roots vacuum pump (25) and the rotary vane vacuum pump (28) are electrically connected to an external power source.

6. A leather vacuum dryer with explosion-proof safety function according to claim 1, characterized in that: The vacuum dryer body (1) is equipped with a cabinet door (11) on its left side.

7. A leather vacuum dryer with explosion-proof safety function according to claim 1, characterized in that: A controller (12) is installed on the upper front side of the vacuum dryer body (1), and the output end of the controller (12) is electrically connected to the Roots vacuum pump (25) and the rotary vane vacuum pump (28).

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