Water ring vacuum unit

Abstract

The utility model discloses a water ring vacuum unit which comprises a water ring pump, a gas-liquid separator, a heat exchanger and a control system, a liquid level sensor is arranged on the gas-liquid separator, a temperature sensor is arranged on a water supplementing pipeline, communicated with an outlet of the heat exchanger, of the water ring pump, and an air pressure sensor and a control valve are arranged on a suction pipeline of the water ring pump. The liquid level sensor is provided with a water replenishing valve and a drain valve, and the heat exchanger is provided with a cooling water inlet adjusting valve. The water ring vacuum unit can meet various working condition requirements such as suction vacuum change and constant mass flow rate, suction vacuum constant and mass flow rate change, and overcomes the defects that electric energy is wasted due to the fact that a traditional water ring vacuum unit adjusts vacuum through a backflow control method, and water is wasted due to long running water of cooling water of a heat exchanger. In addition, the intelligent valve group is adopted to replace a manual water replenishing and draining mode of a gas-liquid separator of a traditional water ring vacuum unit, and intelligent control is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of vacuum units, in particular to a water ring vacuum unit. Background Art

[0002] As vacuum equipment, water ring vacuum units are widely used in various fields such as petroleum, chemical industry, papermaking, medicine and food. They have the advantages of stable operation, large air extraction volume, low energy consumption and adaptability to complex working conditions.

[0003] The operation of water ring vacuum units consumes electricity and water. As the energy-saving requirements of various industries and processes become more and more stringent, the requirements for energy saving and water saving also need to be paid more and more attention. At the same time, the process requirements for vacuum performance are becoming more and more stringent. For processes such as vacuum filtration, vacuum degassing, vacuum evaporation, and vacuum concentration, some working conditions require the suction vacuum to change while the mass flow rate is constant, and some working conditions require the suction vacuum to be constant while the mass flow rate changes. Some process systems may require frequent switching between the two working conditions. Existing water ring vacuum units, such as a water ring vacuum pump unit disclosed in the invention patent with Chinese patent publication number CN104358688A, are only connected by multiple Roots vacuum pumps and valves, and cannot achieve water saving, electricity saving, and adaptability to working conditions. Utility Model Content

[0004] Purpose of the utility model: The purpose of the utility model is to provide an energy-saving water ring vacuum unit with intelligent control.

[0005] Technical solution: The utility model is a water ring vacuum unit, comprising a water ring pump, a gas-liquid separator, and a heat exchanger, wherein the water ring pump is respectively connected to the inlet of the gas-liquid separator and the outlet of the heat exchanger, and the outlet of the gas-liquid separator is connected to the inlet of the heat exchanger. The utility model is characterized in that it also includes a control system, wherein a liquid level sensor is provided on the gas-liquid separator, a temperature sensor is provided on the water supply pipe connecting the water ring pump and the outlet of the heat exchanger, and an air pressure sensor and a control valve are provided on the suction pipe of the water ring pump.

[0006] Furthermore, the liquid level sensor is provided with a water supply valve and a water discharge valve.

[0007] Furthermore, the water supply valve and / or the water discharge valve both adopt a valve group type.

[0008] Furthermore, the heat exchanger is provided with a cooling water inlet regulating valve.

[0009] Furthermore, the cooling water inlet regulating valve adopts a valve group type.

[0010] Furthermore, the valve group includes a regulating valve, and manual valves are arranged before and after the regulating valve.

[0011] Furthermore, the valve group is also provided with a secondary line valve.

[0012] Furthermore, the control system is a PLC frequency conversion control cabinet, and the frequency conversion control cabinet is communicatively connected with the liquid level sensor, the temperature sensor and the air pressure sensor respectively.

[0013] Working principle: The pressure sensor transmits the pressure signal of the inhaled gas to the control system (PLC frequency conversion control cabinet). According to the vacuum requirements, the (PLC) program in the control system (PLC frequency conversion control cabinet) is set. By realizing the frequency conversion control of the motor to adjust the vacuum changes, the vacuum degree can be adjusted by avoiding the use of reflux to adjust the vacuum degree, which can not only achieve stable control of the vacuum degree, but also achieve the purpose of saving electric energy. Specifically: the working water temperature signal of the water ring pump is transmitted to the control system (PLC frequency conversion control cabinet). According to the working water temperature requirements of the water ring pump, the opening of the heat exchanger cooling water inlet regulating valve is controlled to adjust the flow rate, avoiding the waste of cooling water caused by long-term constant cooling water flow, and saving the electric energy consumed by providing cooling water. The liquid level signal of the gas-liquid separator is transmitted to the control system (PLC frequency conversion control cabinet). According to the liquid level requirements of the gas-liquid separator, the opening of the water supply regulating valve is controlled to automatically replenish water. When the water content of the suction medium increases, the control system (PLC frequency conversion control cabinet) controls the drainage regulating valve to automatically drain water, which can meet the requirements of different medium working conditions and achieve the purpose of saving the amount of water supply. At the same time, further, the heat exchanger cooling water inlet regulating valve, water supply regulating valve and drainage regulating valve all adopt valve group type, manual valves are set before and after the regulating valve, and a bypass valve is set at the same time, which can realize online removal maintenance and troubleshooting.

[0014] Beneficial effects: Compared with the prior art, the utility model has the following advantages: (1) The utility model can realize variable frequency control to adjust the vacuum degree according to the vacuum degree requirement, avoid the use of reflux method to adjust the vacuum degree, and can not only realize stable control of the vacuum degree, but also save electric energy; (2) The utility model can control the opening of the heat exchanger cooling water inlet regulating valve to adjust the flow according to the working water temperature requirement of the water ring pump, avoid the waste of cooling water caused by long-term constant cooling water flow, and save the electric energy consumed by providing cooling water; (3) The utility model can control the opening of the water supply regulating valve to automatically replenish water according to the liquid level requirement of the gas-liquid separator. When the water content of the pumped medium increases, the PLC frequency conversion control cabinet controls the drainage regulating valve to automatically drain the water, which can meet the requirements of different medium working conditions and achieve the purpose of saving the amount of water supply; (4) The cooling water inlet regulating valve, water supply regulating valve and drainage regulating valve of the heat exchanger of the utility model all adopt valve group type, and manual valves are set before and after the regulating valve, and a secondary line valve is set at the same time, which can realize online removal maintenance and fault troubleshooting. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the utility model. DETAILED DESCRIPTION

[0016] The technical solution of the utility model is further described below in conjunction with the accompanying drawings.

[0017] As shown in the figure, the utility model provides a water ring vacuum unit, including a water ring pump 1, a gas-liquid separator 2, and a heat exchanger 3. The water ring pump 1 is connected to the inlet of the gas-liquid separator 2 and the outlet of the heat exchanger 3 respectively, and the outlet of the gas-liquid separator 2 is connected to the inlet of the heat exchanger 3. It also includes a control system 4. A liquid level sensor 5 is provided on the gas-liquid separator 2. A temperature sensor 6 is provided on the water supply pipe connecting the water ring pump 1 and the outlet of the heat exchanger 3. An air pressure sensor 7 and a control valve are provided on the suction pipe of the water ring pump 1. A water supply valve 9 and a drain valve 10 are provided on the liquid level sensor 5. The heat exchanger 3 is provided with a cooling water inlet regulating valve 8.

[0018] In some embodiments, the cooling water inlet regulating valve 8, the water supply valve 9, and the drain valve 10 all adopt a valve group type. The valve group includes a regulating valve. Manual valves are arranged before and after the regulating valve. The valve group is also provided with a bypass valve, which can realize online removal maintenance and troubleshooting.

[0019] In some embodiments, the control system is a PLC frequency conversion control cabinet 4, and the frequency conversion control cabinet 4 is communicatively connected with the liquid level sensor 5, the temperature sensor 6 and the air pressure sensor 7 respectively.

[0020] During operation, the air pressure sensor 7 reads the suction gas pressure, converts it into a 4-20mA analog signal and transmits it to the PLC frequency conversion control module in the PLC frequency conversion control cabinet 4. The PLC frequency conversion control module outputs a 4-20mA analog signal and frequency conversion adjusts the motor speed.

[0021] The temperature sensor 6 reads the working water temperature signal of the water ring pump, converts it into a 4-20mA analog signal and transmits it to the PLC frequency conversion control module in the PLC frequency conversion control cabinet 4. According to the working water temperature setting requirements of the water ring pump 1, the PLC frequency conversion control module outputs a 4-20mA analog signal to control the opening of the heat exchanger cooling water inlet regulating valve group 8 to adjust the cooling water flow.

[0022] The liquid level sensor 5 reads the liquid level signal of the gas-liquid separator, converts it into a 4-20mA analog signal and transmits it to the PLC frequency conversion control module in the PLC frequency conversion control cabinet 4. According to the liquid level requirement of the gas-liquid separator, the opening of the water replenishment regulating valve group 9 is controlled to automatically replenish water; when the liquid level of the gas-liquid separator 2 is high, the PLC frequency conversion control module outputs a 4-20mA current to control the drainage regulating valve group 10 to automatically drain water, and at the same time outputs a signal to control the water replenishment regulating valve group 9 to close.

Claims

1. A water ring vacuum unit, comprising a water ring pump (1), a gas-liquid separator (2), and a heat exchanger (3), wherein the water ring pump (1) is connected to an inlet of the gas-liquid separator (2) and an outlet of the heat exchanger (3), respectively, and the outlet of the gas-liquid separator (2) is connected to an inlet of the heat exchanger (3), characterized in that: It also includes a control system (4), the gas-liquid separator (2) is provided with a liquid level sensor (5), the water supply pipe connecting the water ring pump (1) and the outlet of the heat exchanger (3) is provided with a temperature sensor (6), and the suction pipe of the water ring pump (1) is provided with an air pressure sensor (7) and a control valve.

2. A water ring vacuum unit according to claim 1, characterized in that: The liquid level sensor (5) is provided with a water supply valve (9) and a water discharge valve (10).

3. A water ring vacuum unit according to claim 2, characterized in that: The water supply valve (9) and / or the water discharge valve (10) are both of valve group type.

4. A water ring vacuum unit according to claim 1, characterized in that: The heat exchanger (3) is provided with a cooling water inlet regulating valve (8).

5. A water ring vacuum unit according to claim 4, characterized in that: The cooling water inlet regulating valve (8) adopts a valve group type.

6. A water ring vacuum unit according to claim 3 or 5, characterized in that: The valve group comprises a regulating valve, and manual valves are arranged before and after the regulating valve.

7. A water ring vacuum unit according to claim 6, characterized in that: The valve group is also provided with a secondary line valve.

8. The water ring vacuum unit according to claim 1, characterized in that: The control system (4) is a PLC frequency conversion control cabinet, and the PLC frequency conversion control cabinet is respectively communicatively connected with the liquid level sensor (5), the temperature sensor (6) and the air pressure sensor (7).

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