Anti-cavitation system of formic acid centrifugal pump

Abstract

The utility model discloses a formic acid centrifugal pump anti-cavitation system which comprises two sets of bottom pump systems connected in series through a second communication stop valve (107), the first set of bottom pump system comprises a first bottom pump (103) and a second bottom pump (203) which are arranged in parallel, and the second set of bottom pump system comprises a third bottom pump (303) and a fourth bottom pump (403) which are arranged in parallel. According to the device disclosed by the utility model, through the pipeline arrangement, when the whole system is in high-load operation, low-concentration and low-temperature formic acid materials from the first group of bottom pump systems are conveyed to the second group of bottom pump systems, so that the concentration and the temperature of pumped materials of the second group of bottom pump systems are reduced, and blades in pumps are protected. According to the device, the cavitation problem of the centrifugal pump is solved by utilizing a system optimization method, and the device has a good application prospect.

Description

Technical Field

[0001] The utility model relates to the technical field of centrifugal pump anti-cavitation systems, in particular to a formic acid centrifugal pump anti-cavitation system. Background Art

[0002] Pumps are commonly used equipment in chemical engineering, and their operating status is crucial to the stability of the entire plant. Cavitation is a common problem during pump operation, severely impacting pump performance and lifespan.

[0003] Cavitation, also known as cavitation, refers to the phenomenon of cavernous corrosion damage on metal surfaces in contact with fluids under conditions of high-speed flow and varying pressures. This phenomenon often occurs in the high-speed, reduced-pressure zone at the blade tips of centrifugal pumps. Cavitation is characterized by the initial formation of numerous tiny pits on the metal surface, which gradually expand into cavities, ultimately reducing pump efficiency. The formation of cavitation is also related to the properties of the fluids the pump encounters during operation. The formic acid production process initially produces low-concentration formic acid, approximately 35%. This concentration must be raised to 94% through heating and distillation. To achieve this, the material temperature must be heated to above 165°C. At this high temperature, the material vaporizes upon entering the pump, causing cavitation failure and ineffective material delivery. This necessitates the use of large amounts of water spray pipes for cooling, which not only pollutes but also wastes water resources. The improvement is ineffective, impacting stable production operations. Therefore, to ensure long-term, safe and stable pump operation, it is essential to address cavitation issues in centrifugal pumps through piping configuration and system optimization. Utility Model Content

[0004] The utility model provides a formic acid centrifugal pump anti-cavitation system, which solves the cavitation problem of the formic acid centrifugal pump.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A formic acid centrifugal pump anti-cavitation system includes two bottom pump systems connected in series via a second connecting and shut-off valve (107): the first bottom pump system includes a first bottom pump (103) and a second bottom pump (203) arranged in parallel, and the second bottom pump system includes a third bottom pump (303) and a fourth bottom pump (403) arranged in parallel. In this preferred embodiment, the first bottom pump system and the second bottom pump system are connected in series by providing the second connecting and shut-off valve (107):

[0007] When the entire system is running at low load, the second communication shut-off valve (107) is in a closed state, and the first bottom pump system and the second bottom pump system are running separately. The first bottom pump system includes a first bottom pump (103) and a second bottom pump (203) arranged in parallel, and the material entering the inlet is a low-concentration, low-temperature formic acid material. During low-load production, the first bottom pump system only opens the line where the first bottom pump (103) is located; during medium-load production, in order to alleviate the cavitation of the blades of the first bottom pump (103) caused by high flow, the first bottom pump system simultaneously opens the line where the first bottom pump (103) is located and the line where the second bottom pump (203) is located, thereby reducing the flow carried by the blades of a single pump. The second bottom pump system comprises a third bottom pump (303) and a fourth bottom pump (403) arranged in parallel, and the material entering the inlet thereof is a high-concentration and high-temperature formic acid material. During low-load production, the second bottom pump system only opens the line where the third bottom pump (303) is located; during medium-load production, in order to alleviate the cavitation of the blades of the third bottom pump (303) caused by the high flow, the first bottom pump system simultaneously opens the line where the third bottom pump (303) is located and the line where the fourth bottom pump (403) is located, thereby reducing the flow carried by the blades of a single pump.

[0008] When the entire system is running at high load, since cavitation cannot be avoided even if both bottom pumps of the second bottom pump system are turned on at the same time, the second communication shut-off valve (107) is in an open state, and the first bottom pump system and the second bottom pump system are connected to each other, and the low-concentration and low-temperature formic acid material from the first bottom pump system is transported to the second bottom pump system, thereby reducing the concentration and temperature of the material entering the second bottom pump system and protecting the blades inside the pump.

[0009] Furthermore, the material inlet and outlet of the first bottom pump (103) are connected to the first bottom pump inlet filter (102) and the first bottom pump outlet check valve (104) respectively. In this preferred embodiment, the material entering the first bottom pump (103) is filtered by the first bottom pump inlet filter (102), and the material backflow is prevented by the first bottom pump outlet check valve (104).

[0010] Furthermore, the material inlet and outlet of the second bottom pump (203) are connected to the second bottom pump inlet filter (202) and the second bottom pump outlet check valve (204) respectively. In this preferred embodiment, the material entering the second bottom pump (203) is filtered by the second bottom pump inlet filter (202), and the material backflow is prevented by the second bottom pump outlet check valve (204).

[0011] Furthermore, the inlet ends of the first bottom pump inlet shut-off valve (101) and the second bottom pump inlet shut-off valve (201) are connected to the external raw material inlet after merging through a pipeline, and the outlet ends are connected to the first bottom pump inlet filter (102) and the second bottom pump inlet filter (202) respectively. In this preferred embodiment, the entry of the external raw material is controlled by the first bottom pump inlet shut-off valve (101) and the second bottom pump inlet shut-off valve (201), respectively. After the external raw material enters, the first bottom pump inlet filter (102) and the second bottom pump inlet filter (202) filter the entering raw material.

[0012] Furthermore, the material inlet ends of the first bottom pump outlet shut-off valve (105) and the second bottom pump outlet shut-off valve (205) are connected to the first bottom pump outlet check valve (104) and the second bottom pump outlet check valve (204) respectively, and the outlet end pipelines are connected to the first connecting shut-off valve (106) and the second connecting shut-off valve (107) after merging. In this preferred embodiment, the first bottom pump outlet shut-off valve (105) and the second bottom pump outlet shut-off valve (205) respectively control the material passing through the first bottom pump outlet check valve (104) and the second bottom pump outlet check valve (204). The first connecting shut-off valve (106) controls the material to be directly discharged to the next working section, and the second connecting shut-off valve (107) controls the material to flow to the second group of bottom pump systems.

[0013] Furthermore, the material inlet and outlet of the third bottom pump (303) are connected to the third bottom pump inlet filter (302) and the third bottom pump outlet check valve (304) respectively. In this preferred embodiment, the material entering the third bottom pump (303) is filtered by the third bottom pump inlet filter (302), and the material backflow is prevented by the third bottom pump outlet check valve (304).

[0014] Furthermore, the material inlet and outlet of the fourth bottom pump (403) are connected to the fourth bottom pump inlet filter (402) and the fourth bottom pump outlet check valve (404) respectively. In this preferred embodiment, the material entering the fourth bottom pump (403) is filtered by the fourth bottom pump inlet filter (402), and the material backflow is prevented by the fourth bottom pump outlet check valve (404).

[0015] Furthermore, the inlet ends of the third bottom pump inlet shut-off valve (301) and the fourth bottom pump inlet shut-off valve (401) are connected to the third connecting shut-off valve (108) after being merged through a pipeline, and the outlet ends are connected to the third bottom pump inlet filter (302) and the fourth bottom pump inlet filter (402) respectively. In this preferred embodiment, the entry of external raw materials is controlled by the third bottom pump inlet shut-off valve (301) and the fourth bottom pump inlet shut-off valve (401), respectively. After the external raw materials enter, the third bottom pump inlet filter (302) and the fourth bottom pump inlet filter (402) filter the entering raw materials.

[0016] Furthermore, the material inlet ends of the third bottom pump outlet shut-off valve (305) and the fourth bottom pump outlet shut-off valve (405) are connected to the third bottom pump outlet check valve (304) and the fourth bottom pump outlet check valve (404), respectively, and the outlet end pipelines are connected to the external raw material outlet after merging. In this preferred embodiment, the third bottom pump outlet shut-off valve (305) and the fourth bottom pump outlet shut-off valve (405) respectively control the material passing through the third bottom pump outlet check valve (304) and the fourth bottom pump outlet check valve (404).

[0017] The technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0018] (1) The utility model connects the first bottom pump system and the second bottom pump system in series by setting a second connecting shut-off valve (107): when the overall system is running at low load, the second connecting shut-off valve (107) is in a closed state, and the first bottom pump system and the second bottom pump system are running separately. The first bottom pump system includes a first bottom pump (103) and a second bottom pump (203) arranged in parallel, and the material entering the inlet is a low-concentration low-temperature formic acid material. During low-load production, the first bottom pump system only opens the line where the first bottom pump (103) is located; during medium-load production, in order to alleviate the cavitation of the blades of the first bottom pump (103) caused by high flow, the first bottom pump system simultaneously opens the line where the first bottom pump (103) is located and the line where the second bottom pump (203) is located, thereby reducing the flow carried by the blades of a single pump. The second bottom pump system includes a third bottom pump (303) and a fourth bottom pump (403) arranged in parallel. The material entering the inlet of the second bottom pump system is a high-concentration, high-temperature formic acid material. During low-load production, the second bottom pump system only opens the line where the third bottom pump (303) is located. During medium-load production, in order to alleviate the cavitation of the blades of the third bottom pump (303) caused by the high flow rate, the first bottom pump system simultaneously opens the line where the third bottom pump (303) is located and the line where the fourth bottom pump (403) is located, thereby reducing the flow rate carried by the blades of a single pump. When the entire system is running at high load, since cavitation cannot be avoided even if both bottom pumps of the second bottom pump system are opened at the same time, the second communication shut-off valve (107) is in an open state, and the first bottom pump system and the second bottom pump system are connected to each other, and the low-concentration, low-temperature formic acid material from the first bottom pump system is transported to the second bottom pump system, thereby reducing the concentration and temperature of the material entering the second bottom pump system and protecting the blades inside the pump.

[0019] (2) The utility model filters the material entering the first bottom pump (103) through the first bottom pump inlet filter (102), and prevents the material from flowing back through the first bottom pump outlet check valve (104). The material entering the second bottom pump (203) is filtered through the second bottom pump inlet filter (202), and prevents the material from flowing back through the second bottom pump outlet check valve (204). The entry of external raw materials is controlled by the first bottom pump inlet shut-off valve (101) and the second bottom pump inlet shut-off valve (201), respectively. After the external raw materials enter, the first bottom pump inlet filter (102) and the second bottom pump inlet filter (202) filter the entering raw materials. The first bottom pump outlet shut-off valve (105) and the second bottom pump outlet shut-off valve (205) respectively control the flow of materials through the first bottom pump outlet check valve (104) and the second bottom pump outlet check valve (204). The first connecting shut-off valve (106) controls the material to be discharged directly to the next process section, and the second connecting shut-off valve (107) controls the material to flow to the second bottom pump system. The third bottom pump inlet filter (302) filters the material entering the third bottom pump (303), and the third bottom pump outlet check valve (304) prevents the material from flowing back. The fourth bottom pump inlet filter (402) filters the material entering the fourth bottom pump (403), and the fourth bottom pump outlet check valve (404) prevents the material from flowing back. The entry of external raw materials is controlled by the third bottom pump inlet shut-off valve (301) and the fourth bottom pump inlet shut-off valve (401). After the external raw materials enter, the third bottom pump inlet filter (302) and the fourth bottom pump inlet filter (402) filter the incoming raw materials. The third bottom pump outlet cut-off valve (305) and the fourth bottom pump outlet cut-off valve (405) control the materials passing through the third bottom pump outlet check valve (304) and the fourth bottom pump outlet check valve (404) respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0021] In the figure: 101, first bottom pump inlet shut-off valve; 102, first bottom pump inlet filter; 103, first bottom pump; 104, first bottom pump outlet check valve; 105, first bottom pump outlet shut-off valve; 201, second bottom pump inlet shut-off valve; 202, second bottom pump inlet filter; 203, second bottom pump; 204, second bottom pump outlet check valve; 205, second bottom pump outlet shut-off valve; 301, third bottom pump inlet shut-off valve; 302, third bottom pump inlet filter; 303, third bottom pump; 304, third bottom pump outlet check valve; 305, third bottom pump outlet shut-off valve; 401, fourth bottom pump inlet shut-off valve; 402, fourth bottom pump inlet filter; 403, fourth bottom pump; 404, fourth bottom pump outlet check valve; 405, fourth bottom pump outlet shut-off valve; 106, first connecting shut-off valve; 107, second connecting shut-off valve; 108, third connecting shut-off valve. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the technical solution of the present application will be described in detail below in conjunction with specific embodiments. It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which this application belongs.

[0023] Refer to the attached Figure 1As shown, an embodiment of the present invention provides a formic acid centrifugal pump anti-cavitation system, comprising two bottom pump systems connected in series via a second connecting shut-off valve 107: the first bottom pump system comprises a first bottom pump 103 and a second bottom pump 203 arranged in parallel, and the second bottom pump system comprises a third bottom pump 303 and a fourth bottom pump 403 arranged in parallel. The material inlet and outlet of the first bottom pump 103 are respectively connected to the first bottom pump inlet filter 102 and the first bottom pump outlet check valve 104. The material inlet and outlet of the second bottom pump 203 are respectively connected to the second bottom pump inlet filter 202 and the second bottom pump outlet check valve 204. The inlet ends of the first bottom pump inlet shut-off valve 101 and the second bottom pump inlet shut-off valve 201 are connected to an external raw material inlet after merging through a pipeline, and the outlet ends are respectively connected to the first bottom pump inlet filter 102 and the second bottom pump inlet filter 202. The material inlets of the first and second bottom pump outlet shut-off valves 105 and 205 are connected to the first and second bottom pump outlet check valves 104 and 204, respectively. The outlet pipelines merge and then connect to the first and second communication shut-off valves 106 and 107. The material inlet and outlet of the third bottom pump 303 are connected to the third bottom pump inlet filter 302 and the third bottom pump outlet check valve 304, respectively. The material inlet and outlet of the fourth bottom pump 403 are connected to the fourth bottom pump inlet filter 402 and the fourth bottom pump outlet check valve 404, respectively. The inlets of the third and fourth bottom pump inlet shut-off valves 301 and 401 merge and then connect to the third communication shut-off valve 108. Their outlets are connected to the third and fourth bottom pump inlet filters 302 and 402, respectively. The material inlet ends of the third bottom pump outlet shut-off valve 305 and the fourth bottom pump outlet shut-off valve 405 are respectively connected to the third bottom pump outlet check valve 304 and the fourth bottom pump outlet check valve 404, and the outlet end pipelines are connected to the external raw material outlet after merging.

[0024] When the present invention is in use, the first and second bottom pump systems are connected in series by providing a second connecting shut-off valve 107. When the overall system is operating at a low load, the second connecting shut-off valve 107 is closed, and the first and second bottom pump systems operate separately. The first bottom pump system includes a first bottom pump 103 and a second bottom pump 203 connected in parallel, and the material entering the first and second bottom pumps is a low-concentration, low-temperature formic acid material. During low-load production, the first bottom pump system only opens the line containing the first bottom pump 103. During medium-load production, in order to alleviate the cavitation of the blades of the first bottom pump 103 caused by high flow, the first bottom pump system simultaneously opens the line containing the first bottom pump 103 and the line containing the second bottom pump 203, thereby reducing the flow carried by the blades of a single pump. The second bottom pump system includes a third bottom pump 303 and a fourth bottom pump 403 arranged in parallel. The material entering its inlet is a high-concentration, high-temperature formic acid material. During low-load production, the second bottom pump system only opens the line containing the third bottom pump 303. During medium-load production, to alleviate cavitation of the blades of the third bottom pump 303 caused by high flow, the first bottom pump system simultaneously opens the lines containing the third bottom pump 303 and the fourth bottom pump 403, reducing the flow rate carried by the blades of a single pump. When the entire system is operating at high load, because cavitation cannot be avoided even if both bottom pumps of the second bottom pump system are opened simultaneously, the second connecting shut-off valve 107 is opened, and the first and second bottom pump systems are connected to each other, transporting the low-concentration, low-temperature formic acid material from the first bottom pump system to the second bottom pump system, reducing the concentration and temperature of the material entering the second bottom pump system and protecting the blades within the pumps.

[0025] The present invention filters the material entering the first bottom pump 103 through the first bottom pump inlet filter 102, and prevents the material from flowing back through the first bottom pump outlet check valve 104. The material entering the second bottom pump 203 is filtered through the second bottom pump inlet filter 202, and prevents the material from flowing back through the second bottom pump outlet check valve 204. The entry of external raw materials is controlled by the first bottom pump inlet shut-off valve 101 and the second bottom pump inlet shut-off valve 201, respectively. After the external raw materials enter, the first bottom pump inlet filter 102 and the second bottom pump inlet filter 202 filter the entering raw materials. The first bottom pump outlet shut-off valve 105 and the second bottom pump outlet shut-off valve 205 control the material passing through the first bottom pump outlet check valve 104 and the second bottom pump outlet check valve 204, respectively. The first connecting shut-off valve 106 controls the material to be discharged directly to the next work section, and the second connecting shut-off valve 107 controls the material flow to the second bottom pump system. The material entering the third bottom pump 303 is filtered by the third bottom pump inlet filter 302, and the material backflow is prevented by the third bottom pump outlet check valve 304. The material entering the fourth bottom pump 403 is filtered by the fourth bottom pump inlet filter 402, and the material backflow is prevented by the fourth bottom pump outlet check valve 404. The entry of external raw materials is controlled by the third bottom pump inlet shut-off valve 301 and the fourth bottom pump inlet shut-off valve 401, respectively. After the external raw materials enter, the third bottom pump inlet filter 302 and the fourth bottom pump inlet filter 402 filter the incoming raw materials. The third bottom pump outlet shut-off valve 305 and the fourth bottom pump outlet shut-off valve 405 control the material passing through the third bottom pump outlet check valve 304 and the fourth bottom pump outlet check valve 404, respectively.

[0026] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A formic acid centrifugal pump anti-cavitation system, characterized in that: The invention comprises two bottom pump systems connected in series via a second communication cut-off valve (107): the first bottom pump system comprises a first bottom pump (103) and a second bottom pump (203) arranged in parallel, and the second bottom pump system comprises a third bottom pump (303) and a fourth bottom pump (403) arranged in parallel.

2. The formic acid centrifugal pump anti-cavitation system according to claim 1, characterized in that: The material inlet and outlet of the first bottom pump (103) are connected to the first bottom pump inlet filter (102) and the first bottom pump outlet check valve (104) respectively.

3. The formic acid centrifugal pump anti-cavitation system according to claim 1, characterized in that: The material inlet and outlet of the second bottom pump (203) are connected to the second bottom pump inlet filter (202) and the second bottom pump outlet check valve (204) respectively.

4. The formic acid centrifugal pump anti-cavitation system according to claim 1, characterized in that: The inlet ends of the first bottom pump inlet cut-off valve (101) and the second bottom pump inlet cut-off valve (201) are connected to the external raw material inlet after being merged through a pipeline, and the outlet ends are connected to the first bottom pump inlet filter (102) and the second bottom pump inlet filter (202) respectively.

5. The formic acid centrifugal pump anti-cavitation system according to claim 1, characterized in that: The material inlet ends of the first bottom pump outlet shut-off valve (105) and the second bottom pump outlet shut-off valve (205) are connected to the first bottom pump outlet check valve (104) and the second bottom pump outlet check valve (204) respectively, and the outlet end pipelines are connected to the first communication shut-off valve (106) and the second communication shut-off valve (107) after merging.

6. The formic acid centrifugal pump anti-cavitation system according to claim 1, characterized in that: The material inlet and outlet of the third bottom pump (303) are connected to the third bottom pump inlet filter (302) and the third bottom pump outlet check valve (304) respectively.

7. The formic acid centrifugal pump anti-cavitation system according to claim 1, characterized in that: The material inlet and outlet of the fourth bottom pump (403) are connected to the fourth bottom pump inlet filter (402) and the fourth bottom pump outlet check valve (404) respectively.

8. The formic acid centrifugal pump anti-cavitation system according to claim 1, characterized in that: The inlet ends of the third bottom pump inlet shut-off valve (301) and the fourth bottom pump inlet shut-off valve (401) are connected to the third communication shut-off valve (108) after being merged through a pipeline, and the outlet ends are connected to the third bottom pump inlet filter (302) and the fourth bottom pump inlet filter (402) respectively.

9. The formic acid centrifugal pump anti-cavitation system according to claim 1, characterized in that: The material inlet ends of the third bottom pump outlet shut-off valve (305) and the fourth bottom pump outlet shut-off valve (405) are respectively connected to the third bottom pump outlet check valve (304) and the fourth bottom pump outlet check valve (404), and the outlet end pipelines are connected to the external raw material outlet after merging.

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