Vacuum roots pump cleaning device for lactide production

Abstract

The utility model provides a kind of vacuum roots pump cleaning device for propylene lactone production, it is related to chemical equipment technical field, mainly for solving the problem that solid crystalline in prior art can make vacuum roots pump wear, leading to serious decline in pumping efficiency.This cleaning device includes the exhaust pipe and exhaust passage being set on vacuum roots pump, detachable liquid discharge tank is set in the bottom of exhaust passage, spray ring is set in exhaust pipe, suction tube and liquid storage box are set outside exhaust pipe, spray ring is communicated with suction tube, for the cleaning fluid in liquid storage box is inhaled into exhaust pipe and forms spray.This cleaning device does not rely on external power, only rely on the negative pressure generated when vacuum roots pump works can realize the cleaning of vacuum roots pump cavity and rotor, prolongs the service life of vacuum roots pump.This cleaning device simple structure, easy to operate, low in manufacturing cost, strong practicality.

Description

Technical Field

[0001] This utility model is specifically a vacuum Roots pump cleaning device for lactide production, which relates to the field of chemical equipment technology. Background Technology

[0002] D- and L-lactide are characterized by their renewability and biocompatibility. As a key precursor of polylactic acid (PLA), lactide is widely used in biodegradable materials, biomedical materials, 3D printing materials and other fields.

[0003] In the production process of lactide, a vacuum Roots pump is required to evacuate the fixed-bed pyrolysis reactor. During this evacuation process, some gaseous reactants inevitably enter the vacuum Roots pump and form solid crystals. The vacuum Roots pump is a type of vacuum pump without internal compression, relying on a pair of figure-eight rotors rotating in opposite directions within the pump chamber to achieve evacuation. A key characteristic of the vacuum Roots pump is that there is no contact between the rotors or between the rotor and the pump casing, with a gap of 0.1–0.5 mm. If the solid crystals are not removed promptly, wear will occur between the rotors and between the rotor and the pump casing, leading to a significant decrease in evacuation efficiency. Therefore, a cleaning device for the vacuum Roots pump used in lactide production needs to be designed. Utility Model Content

[0004] To overcome the shortcomings of the prior art, this utility model discloses a vacuum Roots pump cleaning device for lactide production, which adopts the following technical solution:

[0005] A vacuum roots pump cleaning device for lactide production, the vacuum roots pump including a suction pipe and an exhaust pipe, a spray ring is provided inside the suction pipe, and a suction pipe and a liquid storage box are provided outside the suction pipe. The spray ring is connected to the suction pipe and is used to draw the cleaning liquid in the liquid storage box into the suction pipe to form a spray. A detachable drain tank is provided at the bottom of the exhaust pipe.

[0006] Further improve the technical solution: A connecting pipe is sealed and installed on the suction pipe, and the spray ring is connected to the suction pipe through the connecting pipe.

[0007] Further improved technical solution: The straw is set vertically, and the connecting tube is horizontally connected to the straw, forming a three-way structure with the straw; a nut is screwed to the top of the straw, and the nut has a rubber plug that extends into the straw to close or open the three-way structure.

[0008] Further improve the technical solution: multiple nozzles are evenly distributed at the bottom of the spray ring.

[0009] Further improvement to the technical solution: The drain tank is screwed to the bottom of the exhaust duct.

[0010] Further improve the technical solution: The cleaning fluid is high-temperature water or an organic solvent.

[0011] After implementing the above technical solution, the beneficial effects of this utility model compared to the prior art are:

[0012] This cleaning device has a spray ring inside the suction pipe and a suction tube and a liquid storage box outside the suction pipe. The cleaning liquid in the liquid storage box can be drawn into the suction pipe and formed into a spray by using negative pressure.

[0013] This cleaning device does not require external power; it only relies on the negative pressure generated by the vacuum Roots pump during operation to clean the pump chamber and rotor, thus extending the service life of the vacuum Roots pump.

[0014] This cleaning device has a simple structure, is easy to operate, has low manufacturing cost, and is highly practical. Attached Figure Description

[0015] Appendix Figure 1 The diagram shown is a schematic representation of the overall structure of this vacuum Roots pump cleaning device.

[0016] Appendix Figure 2 The attached image shows the attached image. Figure 1 A partial structural diagram.

[0017] Appendix Figure 3 The attached image shows the attached image. Figure 2 A schematic diagram of the cross-sectional structure of AA.

[0018] Appendix Figure 4 The diagram shows the structure of the cleaning device when cleaning a vacuum Roots pump.

[0019] In the attached diagram: 1. Vacuum Roots pump; 11. Pump body; 12. Suction pipe; 13. Exhaust duct; 14. Exhaust pipe; 2. Spray ring; 21. Nozzle; 3. Connecting pipe; 4. Suction tube; 5. Liquid storage box; 6. Drainage tank; 7. Cleaning fluid; 81. Nut; 82. Connecting rod; 83. Rubber stopper. Detailed Implementation

[0020] The preferred embodiments of this utility model are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of this utility model and are not intended to limit the scope of protection of this utility model. It should be noted that in the description of this utility model, terms such as "front," "rear," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is merely for ease of description and does not indicate or imply that the device or element must have a specific orientation and positional relationship, and therefore should not be construed as a limitation of this utility model. It should also be noted that in the description of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0021] A vacuum roots pump cleaning device for lactide production, relating to the field of chemical equipment technology, is disclosed. It primarily addresses the problem in existing technologies where solid crystals cause wear on vacuum roots pumps, leading to a significant decrease in pumping efficiency. The composition and working principle of this cleaning device are described in detail below.

[0022] See attached document Figure 1 The vacuum Roots pump 1 mainly consists of a pump body 11, an exhaust passage 13, an exhaust pipe 14, and a suction pipe 12. A pair of figure-eight rotors are installed in the pump chamber of the pump body 11. During operation, the air in the suction pipe 12 is drawn into the exhaust passage 13 by the counter-rotation of the pair of figure-eight rotors, and then discharged from the pump through the exhaust pipe 14.

[0023] See attached document Figure 2 and attached Figure 3 To address the problems in the background art, a spray ring 2 is provided inside the suction pipe 12, and a suction pipe 4 and a liquid storage box 5 are provided outside the suction pipe 12. The spray ring 2 is connected to the suction pipe 4 and is used to draw the cleaning liquid 7 in the liquid storage box 5 into the suction pipe 12 to form a spray.

[0024] Specifically, a connecting pipe 3 is sealed and installed on the suction pipe 12. The spray ring 2 is connected to the suction pipe 4 through the connecting pipe 3. Multiple nozzles 21 are evenly distributed at the bottom of the spray ring 2. The suction pipe 4 is vertically arranged, and the connecting pipe 3 is horizontally connected to the suction pipe 4, forming a three-way structure with the suction pipe 4. A nut 81 is screwed to the top of the suction pipe 4. The nut 81 has a rubber plug 83 that extends into the suction pipe 4 to close or open the three-way structure. The rubber plug 83 is connected to the lower end of the nut 81 through a connecting rod 82.

[0025] Existing Roots pumps are U-shaped and lack a drainage structure. To facilitate the discharge of used cleaning fluid, a removable drainage tank 6 is provided at the bottom of the exhaust duct 13. The function of the drainage tank 6 is to collect the used cleaning fluid inside the vacuum Roots pump 1. In this embodiment, the drainage tank 6 is screwed to the bottom of the exhaust duct 13.

[0026] Working principle:

[0027] See attached document Figure 2 When cleaning is not required, turn the nut 81 downwards to seal the tee structure with the rubber stopper 83. At this time, even if a negative pressure is generated in the suction pipe 12, external air will not enter the suction pipe 12, and the cleaning liquid 7 in the liquid storage box 5 will not be able to enter the spray ring 2.

[0028] See attached document Figure 4 When the vacuum roots pump 1 is working, a negative pressure is generated in the suction pipe 12. When cleaning the vacuum roots pump 1 is required, turn the nut 81 upwards to open the rubber stopper 83, which seals the three-way valve. At this time, under the negative pressure in the suction pipe 12, the cleaning liquid 7 in the storage box 5 enters the suction pipe 4 and then enters the spray ring 2 through the connecting pipe 3, ultimately forming a spray through the jet effect of the nozzle 21. The cleaning liquid 7 can be high-temperature water or an organic solvent, such as acetone, ethanol, or chloroform.

[0029] The spray enters the pump chamber with the airflow, cleaning or dissolving solid crystals adhering to the pump chamber and rotor. The cleaning fluid 7 then enters the drain tank 6 through the exhaust duct 13. The drain tank 6 has a limited capacity, so it needs to be disassembled periodically to empty the cleaning fluid inside.

[0030] Summarize:

[0031] As described above, this cleaning device can clean the pump chamber and rotor of the vacuum Roots pump 1 without the need for external power, relying solely on the negative pressure generated by the vacuum Roots pump 1 during operation, thus extending the service life of the vacuum Roots pump 1. This cleaning device has a simple structure, is easy to operate, has low manufacturing cost, and is highly practical.

[0032] It is worth noting that the content not described in detail in the above embodiments is prior art. It is also worth noting that any additions, subtractions, substitutions, and improvements made by those skilled in the art based on the structure and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A cleaning device for a vacuum roots pump used in lactide production, the vacuum roots pump comprising a suction pipe and an exhaust pipe, characterized in that: A spray ring is installed inside the suction pipe, and a suction pipe and a liquid storage box are installed outside the suction pipe. The spray ring is connected to the suction pipe and is used to draw the cleaning liquid in the liquid storage box into the suction pipe to form a spray. A detachable drain tank is installed at the bottom of the exhaust duct.

2. The vacuum Roots pump cleaning device for lactide production as described in claim 1, characterized in that: A connecting pipe is sealed and installed on the suction pipe, and the spray ring is connected to the suction pipe through the connecting pipe.

3. A vacuum Roots pump cleaning device for lactide production as described in claim 2, characterized in that: The straw is vertically arranged, and the connecting tube is horizontally connected to the straw, forming a three-way structure with the straw; a nut is screwed to the top of the straw, and the nut has a rubber plug that extends into the straw to close or open the three-way structure.

4. A vacuum Roots pump cleaning device for lactide production as described in claim 1, characterized in that: Multiple nozzles are evenly distributed at the bottom of the spray ring.

5. A vacuum Roots pump cleaning device for lactide production as described in claim 1, characterized in that: The drain tank is screwed to the bottom of the exhaust duct.

6. A vacuum Roots pump cleaning device for lactide production as described in claim 1, characterized in that: The cleaning solution is high-temperature water or an organic solvent.

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