A positive displacement compression device with a scroll blower pre-compression unit

Abstract

This invention discloses a positive displacement compressor with a vortex blower pre-compression unit. The device adds a vortex blower as a pre-compression unit to an existing positive displacement compressor. The outlet of the vortex blower is connected to a self-circulating return branch and a pre-compression branch via a three-way pipe. A pre-compression return regulating valve and a first buffer cooling tank are installed on the self-circulating return branch to adjust the return ratio of the pre-compressed gas. The pre-compression branch connects to the rear positive displacement compressor and is sequentially equipped with a second pressure pulsation sensor, a first flow meter, an intermediate pipeline regulating valve, a second buffer cooling tank, and an inlet solenoid valve. Pressure pulsation sensors, flow meters, and various valves are also installed at different locations throughout the device. This invention features high energy efficiency, high system stability and reliability, and low pressure pulsation amplitude.

Description

Technical Field

[0001] This invention belongs to the field of volumetric compression equipment, specifically relating to a volumetric compression device with a vortex blower pre-compression unit. Background Technology

[0002] Driven by the current demand for clean energy gas compression, positive displacement compressors are widely used in energy, chemical, and gas storage and transportation fields. They are characterized by high discharge pressure and stable operating conditions, generally meeting usage requirements during the design phase. However, with energy development and increasing process demands, existing compressor units have gradually revealed the following shortcomings under their original design structure and varying operating conditions: 1. Under high load and high flow conditions, the periodic pulsation of airflow intensifies, which may cause severe vibration of the unit.

[0003] 2. After long-term operation, positive displacement compressors are prone to performance degradation due to wear of key components and alternating loads, which can lead to deviation from the original design conditions and cause a decrease in efficiency and stability.

[0004] 3. The original unit was designed with fixed operating conditions, which made it difficult to adapt to the needs of changing operating conditions and load fluctuations.

[0005] 4. For large units, disassembly and maintenance are difficult, maintenance cycles are long, and downtime costs are high, which makes restoring performance through traditional maintenance methods subject to significant engineering limitations.

[0006] 5. Under different operating conditions, the adjustment methods of throttling, valve control, bypass, and adding pulsation suppressors result in large energy losses and reduced operating efficiency.

[0007] 6. Existing series-parallel modification methods mostly focus on increasing pressure ratio or flow capacity, without considering the matching of flow rate and speed before and after the system, as well as the pulsation transmission characteristics. This can easily introduce new flow-induced excitations and make it difficult to balance operational stability and vibration suppression. Summary of the Invention

[0008] To address the problems of insufficient flow, excessive airflow pulsation, severe unit vibration, and serious energy loss in existing positive displacement compressor units, this invention proposes a positive displacement compressor device with a vortex fan pre-compression unit, which can operate stably under high flow conditions.

[0009] The objective of this invention is achieved through the following technical solution: A positive displacement compressor with a vortex blower pre-compression unit includes a main intake pipe, a main intake valve, and a first pressure pulsation sensor disposed on the main intake pipe; a vortex blower is connected downstream of the first pressure pulsation sensor as a pre-compression unit for drawing in atmospheric pressure gas; the outlet of the vortex blower is connected to a self-circulating return branch and a pre-compression branch via a three-way pipe; a pre-compression return regulating valve and a first buffer cooling tank are disposed on the self-circulating return branch for adjusting the return ratio of the pre-compressed gas from the vortex blower; the pre-compression branch is connected to a positive displacement compressor at the rear end, and a second pressure pulsation sensor, a first flow meter, an intermediate pipeline regulating valve, a second buffer cooling tank, and an intake solenoid valve are disposed sequentially on the pre-compression branch; The positive displacement compressor includes a primary cylinder, a primary exhaust pressure gauge, a first safety valve, a primary cooler, a water-vapor separator, a secondary cylinder, and a main exhaust cooler. The primary cylinder has an atmospheric pressure intake pipe at its inlet, and an atmospheric pressure intake filter and an atmospheric pressure intake switching valve are sequentially installed on the atmospheric pressure intake pipe. The atmospheric pressure intake pipe and the pre-compression branch are connected to the primary cylinder. The primary exhaust pressure gauge and the first safety valve are located between the primary cylinder and the primary cooler. A second safety valve, an unloading solenoid valve, a check valve, a third pressure pulsation sensor, a first exhaust buffer tank, a pressure regulating shut-off valve, a second flow meter, and a second exhaust buffer tank are sequentially installed on the exhaust pipe after the main exhaust cooler. The second exhaust buffer tank and the second buffer cooling tank are connected through a reflux regulating branch, and a reflux regulating branch regulating valve is installed on the reflux regulating branch. The outlet of the second exhaust buffer tank is connected to the main exhaust pipe, and an exhaust valve is installed on the main exhaust pipe.

[0010] Furthermore, it also includes a vibration control device, located on the outer walls of the first-stage cylinder, the second-stage cylinder, and the vortex blower, respectively, for acquiring the vibration response signal of the equipment.

[0011] Furthermore, it also includes a control device, which is connected to all flow meters, pressure pulsation sensors, pressure gauges on the buffer cooling tank and exhaust buffer tank, vibration monitoring devices and various valves, and adjusts the operating status of the device based on real-time acquired pressure, flow, pressure pulsation and vibration signals.

[0012] Furthermore, both the first and second buffer cooling tanks are equipped with pressure gauges to monitor the gas pressure in the buffer cooling tanks at all times.

[0013] A control method for a positive displacement compressor with a vortex blower pre-compression unit includes: Based on the overall flow demand and operating status of the device, a graded adjustment strategy is adopted to control the device: when the flow demand increases, the volumetric flow rate of the entire device is initially controlled by adjusting the opening of the intermediate pipeline regulating valve, so that the vortex blower, as the pre-compression unit, adaptively adjusts its working state according to the changes in back pressure and characteristic curve; at the same time, pressure pulsation and vibration signals are monitored in real time. When the pressure pulsation amplitude or vibration response is detected to increase significantly and approach the set threshold, the speed of the downstream positive displacement compressor is reduced and the speed of the vortex blower, as the pre-compression unit, is increased to readjust the pressure ratio distribution, thereby reducing the pressure ratio borne by the positive displacement compressor and suppressing fluid excitation; When the above adjustments fail to meet the target flow or stability requirements, or when the monitored pressure pulsation and vibration response remain above the preset range, the control device finely regulates the total flow and pressure ratio distribution of the entire device by adjusting the flow of the self-circulation loop of the pre-compressor and the downstream positive displacement compressor, thereby achieving stable operation of the entire device within a wide operating range.

[0014] The beneficial effects of this invention are as follows: 1. Compared to existing positive displacement compressor unit retrofit devices that rely solely on throttling, bypassing, and simple buffering and vibration reduction, this invention introduces a vortex blower pre-compression unit on the intake side of the positive displacement compressor, combined with buffering, pressure stabilization, and reflux regulation units. This optimizes the exhaust conditions while altering the system's intake conditions, without altering the original positive displacement compressor system itself. This avoids large-scale redesign and structural modifications to each stage of the cylinders, reducing the difficulty of engineering implementation. By pre-compressing, the compression load is shared, and the ultra-high-speed vortex blower provides a large flow of pre-compressed gas under stable operation, facilitating efficient gas compression in subsequent cylinder stages and improving the volumetric efficiency of the positive displacement compressor, thereby increasing overall energy utilization efficiency. Furthermore, the high-frequency operation of the vortex blower and the positive displacement compressor has a significant difference in rotational frequency, reducing the likelihood of resonance and further improving the system's stability and reliability.

[0015] 2. This invention uses a vortex blower as the pre-compression device at the front end. Its working characteristics determine that it is not prone to surge instability within the normal operating range. Even under low flow or rapid back pressure adjustment conditions, it can still maintain continuous boost output within a wide range, thereby expanding the original system's operating conditions. At the same time, since it does not have obvious instability boundary limitations, the operating point of the entire device can be adjusted within a wide range of operating conditions. Compared with other dynamic combined compression improvement methods, it can improve the overall energy efficiency of the system while ensuring stable system operation.

[0016] 3. In existing combined compression systems with other power compression devices connected in series at the front end, the high sensitivity of the front-end compressor to flow rate leads to unstable pressurization, while the inherent periodic discharge characteristics of the rear-end positive displacement compressor more easily introduce pressure pulsations, resulting in strong coupling instability in the entire system. This invention, through pre-pressurization by a vortex blower, combined with the regulation of the circulating intake and recirculation ratio under pressure pulsation and vibration monitoring control, can provide a wider range of gas pressure and flow rates. Simultaneously, the intermediate buffer cooling device reduces the reverse impact of the positive displacement compressor on the front-end equipment from the source. Compared with other types of combined compression improvement devices, this invention is more effective in reducing the amplitude of system pressure pulsations and suppressing flow-induced excitation. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a volumetric compression device with a vortex fan pre-compression unit according to an embodiment of the present invention.

[0018] In the diagram, the components are: 1. Main intake valve; 2. Vortex fan; 3. Pre-compression reflux regulating valve; 4. First buffer cooling tank; 5. Intermediate pipeline regulating valve; 6. Second buffer cooling tank; 7. Intake solenoid valve; 8. Atmospheric pressure intake filter; 9. Atmospheric pressure intake switching valve; 10. First stage cylinder; 11. First stage exhaust pressure gauge; 12. First stage cooler; 13. Water vapor separator; 14. Second stage cylinder; 15. Main exhaust cooler; 16. Second safety valve; 17. Unloading solenoid valve; 18. Check valve; 19. Third pressure pulsation sensor; 20. First exhaust buffer tank; 21. Pressure regulating shut-off valve; 22. Second flow meter; 23. Second exhaust buffer tank; 24. Reflux regulating branch regulating valve; 25. Exhaust valve; 26. First flow meter; 27. Second pressure pulsation sensor; 28. First pressure pulsation sensor; 29. Detailed Implementation

[0019] The present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments. The purpose and effects of the present invention will become clearer. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0020] like Figure 1As shown, the positive displacement compressor with a vortex blower pre-compression unit in this embodiment includes a main intake pipe, a main intake valve 1, and a first pressure pulsation sensor 29 disposed on the main intake pipe. The main intake valve 1 is used to control the on / off of the overall atmospheric pressure intake of the device, and the first pressure pulsation sensor 29 is used to synchronize the average pressure and the amplitude-frequency characteristics of pressure fluctuations. A vortex blower 2 is connected downstream of the first pressure pulsation sensor 29, serving as a pre-compression unit for intake of atmospheric pressure gas. Under high flow conditions, it initially increases the pressure, improving the intake level of the original positive displacement compressor. The outlet of the vortex blower 2 is connected to a self-circulating return branch and a pre-compression branch via a three-way pipe. The self-circulating return branch is equipped with a pre-compression return regulating valve 3 and a first buffer cooling tank 4 to adjust the return ratio of the pre-compressed gas from the vortex blower. The pre-compression branch is connected to the subsequent positive displacement compressor. A second pressure pulsation sensor 28, a first flow meter 27, an intermediate pipeline regulating valve 5, a second buffer cooling tank 6, and an intake solenoid valve 7 are sequentially installed on the pre-compression branch. The pre-compressed gas passes sequentially through the intermediate pipeline regulating valve 5 and the buffer cooling tank 6 on the pre-compression branch. The intermediate pipeline regulating valve 5 is used to regulate the back pressure of the vortex blower 2 to achieve flow control; it is a valve with automatic volumetric flow control function, used to further reduce the pulsation transmission between the two compression units. The second buffer cooling tank 6 is used to cool the pre-compressed gas and simultaneously reduce the impact of the pulsating intake of the downstream positive displacement compressor on the operation of the upstream vortex blower. Pressure gauges are installed on the first buffer cooling tank 4 and the second buffer cooling tank 6 to monitor the gas pressure in the buffer cooling tanks at all times. The intake solenoid valve 7 is used to ensure that the circuit is cut off when the intake pressure is lower than a preset value.

[0021] The rear-end positive displacement compressor includes a first-stage cylinder 10, a first-stage exhaust pressure gauge 11, a first safety valve 12, a first-stage cooler 13, a water-vapor separator 14, a second-stage cylinder 15, and a total exhaust cooler 16.

[0022] The inlet of the first-stage cylinder 10 is equipped with an atmospheric pressure intake pipeline, and an atmospheric pressure intake filter device 8 and an atmospheric pressure intake switching valve 9 are installed sequentially on the atmospheric pressure intake pipeline; the atmospheric pressure intake pipeline and the pre-compression branch are connected to the first-stage cylinder 10.

[0023] The first-stage exhaust pressure gauge 11 and the first safety valve 12 are located between the first-stage cylinder 10 and the first-stage cooler 13. The first-stage exhaust pressure gauge 11 is used to monitor the exhaust pressure after the first stage compression, and the first safety valve 12 is used to prevent the pressure from being too high.

[0024] After being cooled by the primary cooler 13, the exhaust gas enters the water-vapor separator 14 to remove condensate and impurities. The filtered gas then undergoes secondary compression via the secondary cylinder 15. The exhaust side of the secondary cylinder 15 is connected to the main exhaust cooler 16 for cooling the high-flow-rate, high-pressure gas.

[0025] A second safety valve 17, an unloading solenoid valve 18, a one-way valve 19, and a third pressure pulsation sensor 20 are sequentially installed on the exhaust pipe between the main exhaust cooler 16 and the exhaust buffer tank 21. The second safety valve 17 is used to safely release pressure when the exhaust exceeds a set pressure; the unloading solenoid valve 18 is used to stop the system and unload high-pressure gas; the cooled gas enters the first exhaust buffer tank 21 after passing through the one-way valve 19 and the third pressure pulsation sensor 20. The exhaust buffer tank 21 is used to stabilize the system's exhaust pressure and reduce exhaust airflow pulsation.

[0026] The outlet of the first exhaust buffer tank 21 is connected to the second exhaust buffer tank 24. A pressure regulating shut-off valve 22 and a second flow meter 23 are sequentially installed on the connecting pipeline to measure the total exhaust flow rate of the system. The volume of the second exhaust buffer tank 24 is larger than that of the first exhaust buffer tank 21, which is used to further stabilize the exhaust pressure of the system and facilitate precise control of the rotational speed and recirculation ratio. The second exhaust buffer tank 24 is connected to the second buffer cooling tank 6 via a recirculation regulating branch, which is used to recirculate a portion of the high-pressure gas back to the low-pressure intake side. This balances the dynamic storage of high-pressure gas when the gas consumption is low, facilitating timely adjustment of the compression time under high-pressure demands. A recirculation regulating branch regulating valve 25 is installed on the recirculation regulating branch. The outlet of the second exhaust buffer tank 24 is connected to the main exhaust pipeline, and an exhaust valve 26 is installed on the main exhaust pipeline.

[0027] The self-circulating return branch set at the outlet of the vortex fan 2, and the return flow regulation branch set between the second buffer cooling tank 6 and the second exhaust buffer tank 24, realize the return flow regulation, and can comprehensively and in real time control the system intake pressure, intake flow and pulsation state under different operating conditions.

[0028] The present invention also includes vibration monitoring devices located on the outer walls of the first-stage cylinder 10, the second-stage cylinder 15, and the vortex fan 2, respectively, for acquiring vibration response signals of key equipment; preferably, vibration monitoring devices are also provided on the outer walls of the second exhaust buffer tank 24 and the second buffer cooling tank 6 to monitor structural vibration caused by pressure pulsation.

[0029] The invention also includes a control device, which is connected to all flow meters, pressure pulsation sensors, pressure gauges on the buffer cooling tank and exhaust buffer tank, vibration monitoring devices, and various valves. Based on real-time acquired pressure, flow, pressure pulsation, and vibration signals, the control device adjusts its operating status, specifically as follows: Based on the overall flow demand and operating status of the device, a graded adjustment strategy is adopted to control the device. When the flow demand increases, the volumetric flow rate of the entire device is initially controlled by adjusting the opening of the intermediate pipeline regulating valve 5. This allows the vortex blower, which serves as the pre-compression unit, to adaptively adjust its working state according to the changes in back pressure and characteristic curves. At the same time, pressure pulsation and vibration signals are monitored in real time. When a significant increase in the amplitude of pressure pulsation or vibration response is detected and it approaches the set threshold, the speed of the downstream positive displacement compressor is reduced and the speed of the vortex blower 2, which serves as the pre-compression unit, is increased to readjust the pressure ratio distribution, thereby reducing the pressure ratio of the positive displacement compressor and suppressing fluid excitation.

[0030] When the above adjustments fail to meet the target flow or stability requirements, or when the monitored pressure pulsation and vibration response remain above the preset range, the control device finely regulates the total flow and pressure ratio distribution of the entire device by adjusting the flow of the self-circulation loop of the pre-compressor and the downstream positive displacement compressor, thereby achieving stable operation of the entire device within a wide operating range.

[0031] It will be understood by those skilled in the art that the above descriptions are merely preferred examples of the invention and are not intended to limit the invention. Although the invention has been described in detail with reference to the foregoing examples, those skilled in the art can still modify the technical solutions described in the foregoing examples or make equivalent substitutions for some of the technical features. All modifications and equivalent substitutions made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A positive displacement compression device with a vortex blower pre-compression unit, characterized in that, The system includes a main intake pipe, a main intake valve, and a first pressure pulsation sensor installed on the main intake pipe. A vortex blower is connected downstream of the first pressure pulsation sensor, serving as a pre-compression unit for drawing in atmospheric pressure gas. The outlet of the vortex blower is connected to a self-circulating return branch and a pre-compression branch via a three-way pipe. A pre-compression return regulating valve and a first buffer cooling tank are installed on the self-circulating return branch to adjust the return ratio of the pre-compressed gas from the vortex blower. The pre-compression branch is connected to a positive displacement compressor at the rear end, and a second pressure pulsation sensor, a first flow meter, an intermediate pipe regulating valve, a second buffer cooling tank, and an intake solenoid valve are installed sequentially on the pre-compression branch. The positive displacement compressor includes a primary cylinder, a primary exhaust pressure gauge, a first safety valve, a primary cooler, a water-vapor separator, a secondary cylinder, and a main exhaust cooler. The primary cylinder has an atmospheric pressure intake pipe at its inlet, and an atmospheric pressure intake filter and an atmospheric pressure intake switching valve are sequentially installed on the atmospheric pressure intake pipe. The atmospheric pressure intake pipe and the pre-compression branch are connected to the primary cylinder. The primary exhaust pressure gauge and the first safety valve are located between the primary cylinder and the primary cooler. A second safety valve, an unloading solenoid valve, a check valve, a third pressure pulsation sensor, a first exhaust buffer tank, a pressure regulating shut-off valve, a second flow meter, and a second exhaust buffer tank are sequentially installed on the exhaust pipe after the main exhaust cooler. The second exhaust buffer tank and the second buffer cooling tank are connected through a reflux regulating branch, and a reflux regulating branch regulating valve is installed on the reflux regulating branch. The outlet of the second exhaust buffer tank is connected to the main exhaust pipe, and an exhaust valve is installed on the main exhaust pipe.

2. The volumetric compression device with a vortex fan pre-compression unit according to claim 1, characterized in that, It also includes a vibration control device, located on the outer wall of the first-stage cylinder, the second-stage cylinder and the vortex blower, respectively, for acquiring the vibration response signal of the equipment.

3. The volumetric compression device with a vortex fan pre-compression unit according to claim 1, characterized in that, It also includes a control device, which is connected to all flow meters, pressure pulsation sensors, pressure gauges on the buffer cooling tank and exhaust buffer tank, vibration monitoring devices and various valves, and adjusts the operating status of the device based on real-time acquired pressure, flow, pressure pulsation and vibration signals.

4. The volumetric compression device with a vortex fan pre-compression unit according to claim 1, characterized in that, Both the first and second buffer cooling tanks are equipped with pressure gauges to monitor the gas pressure in the buffer cooling tanks at all times.

5. A control method for a volumetric compression device with a vortex fan pre-compression unit as described in any one of claims 1 to 4, characterized in that, include: Based on the overall flow demand and operating status of the device, a graded adjustment strategy is adopted to control the device: when the flow demand increases, the volumetric flow rate of the entire device is initially controlled by adjusting the opening of the intermediate pipeline regulating valve, so that the vortex blower, as the pre-compression unit, adaptively adjusts its working state according to the changes in back pressure and characteristic curve; at the same time, pressure pulsation and vibration signals are monitored in real time. When the pressure pulsation amplitude or vibration response is detected to increase significantly and approach the set threshold, the speed of the downstream positive displacement compressor is reduced and the speed of the vortex blower, as the pre-compression unit, is increased to readjust the pressure ratio distribution, thereby reducing the pressure ratio of the positive displacement compressor and suppressing fluid excitation; When the above adjustments fail to meet the target flow or stability requirements, or when the monitored pressure pulsation and vibration response remain above the preset range, the control device finely regulates the total flow and pressure ratio distribution of the entire device by adjusting the flow of the self-circulation loop of the pre-compressor and the downstream positive displacement compressor, thereby achieving stable operation of the entire device within a wide operating range.

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