300MW unit condenser vacuum maintaining device

Abstract

The utility model discloses a 300MW unit condenser vacuum maintaining device, and belongs to the technical field of thermal generator set energy-saving devices. The problems of high energy consumption and low efficiency in the prior art are solved. The system is technically characterized by comprising a condenser, a roots vacuum pump, an interstage cooler, a water ring vacuum pump, a plate heat exchanger, a gas-water separator and a vacuum pump, a pipeline where the condenser is located is divided into three paths, the first path is sequentially and circularly connected with a vacuum pump A, a vacuum pump cooler A and a gas-water separator A, the second path is sequentially and circularly connected with a vacuum pump B, a vacuum pump cooler B and a gas-water separator B, and the third path is sequentially connected with a roots vacuum pump and an interstage cooler. The water ring vacuum pump, the gas-water separator C and the plate heat exchanger are sequentially and circularly connected to form a third loop; according to the utility model, the model is replaced without replacing the motor, additional power system adjustment is not needed, the air suction rate is larger, the vacuum degree is effectively improved, the heat efficiency is improved, and the fuel consumption is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of energy-saving devices for thermal power generating units, in particular to a vacuum maintenance device for a condenser of a 300MW unit. Background Technique

[0002] In the production of thermal power plants, water ring vacuum pumps are generally used. The vacuum pumping equipment establishes vacuum at the initial stage of unit startup and maintains vacuum during normal operation. However, the efficiency of these vacuum pumping equipment is relatively low, generally only about 30%. Therefore, their power is relatively high. On the other hand, the air extraction performance of these vacuum pumping equipment is restricted by the increase in the temperature of the working water. Especially in summer when the water temperature is relatively high, its air extraction performance deviates far from the design value, resulting in a further decrease in the vacuum of the condenser, reducing the economy of the unit, increasing the coal consumption for power generation. At the same time, due to vaporization problems, cavitation occurs inside the water ring vacuum pump, causing damage and even accidents.

[0003] At present, the vacuum pumping equipment widely used in thermal power plants mainly includes two types: water ring vacuum pumps and high-efficiency vacuum pumps (also called roots pumps, which belong to a type of dry pump). Water ring vacuum pumps are generally selected with a larger size and low efficiency, generally less than 40%. The performance and output of water ring vacuum pumps are restricted by the change of the temperature of the working water. When the water ring vacuum pump operates in a high vacuum state for a long time, the impeller is easily damaged by cavitation, and the equipment maintenance cost is high. The high-efficiency vacuum pump has the characteristics of the higher the vacuum degree, the larger the gas volume, and higher working efficiency, generally above 70%. The efficiency of the water ring vacuum pump in high vacuum is generally only about 15%. Even if an air ejector is connected in series, the efficiency can only be increased to about 20%. The high-efficiency vacuum pump is energy-saving and efficient, avoids the water ring vacuum pump working under cavitation conditions, reduces impeller damage, reduces the workload and cost of maintenance; the equipment runs with low noise; the working performance is not restricted by the increase in the temperature of the working water; the ultimate vacuum value is high (less than 400pa), saving the cooling water flow rate.

[0004] For the #1 and #2 units of a certain power plant, the current ZJQL600 roots vacuum pump is equipped with a 2BE1202 water ring vacuum pump, and its air extraction volume is 600L / S. To further improve the vacuum performance of the unit, without replacing the motor and other main components, the existing ZJQL600 roots vacuum pump is replaced with a high-performance ZJQL800 roots vacuum pump, and the air extraction volume of the unit is increased to 800L / S, and the vacuum degree of the condenser is increased by more than 0.2KPa.

[0005] In the prior art, the design of the vacuum pump is unreasonable, and the water ring vacuum pump is used entirely to establish and maintain the vacuum; the selected equipment has high operating energy consumption and low efficiency; the cavitation problem of the vacuum pump cannot be solved; it cannot meet the vacuum maintenance in high-temperature seasons, resulting in a decrease in the unit vacuum, increasing the coal consumption for power generation, and reducing the economy of the unit. Therefore, there is an urgent need to propose a vacuum maintenance device for a condenser of a 300MW unit to solve the problems of high energy consumption and high cost. Summary of the Utility Model

[0006] In view of the above facts, in order to solve the problems of high energy consumption and high cost, the utility model designs a vacuum maintenance device for a 300MW unit condenser.

[0007] To achieve the above object, the utility model adopts the following technical solutions:

[0008] The vacuum maintenance device for a 300MW unit condenser includes: a condenser, a Roots vacuum pump, an inter-stage cooler, a liquid-ring vacuum pump, a plate heat exchanger, a gas-liquid separator, and a vacuum pump;

[0009] The pipeline where the condenser is located is divided into three paths. The first path is connected to the first loop, and the first loop is sequentially and circularly connected to a vacuum pump A, a gas-liquid separator A, and a vacuum pump cooler A;

[0010] The second path is connected to the second loop, and the second loop is sequentially and circularly connected to a vacuum pump B, a vacuum pump cooler B, and a gas-liquid separator B;

[0011] The third path is sequentially connected to the Roots vacuum pump and the inter-stage cooler. The liquid-ring vacuum pump, a gas-liquid separator C, and the plate heat exchanger are sequentially and circularly connected to form the third loop. The liquid-ring vacuum pump is also connected to the Roots vacuum pump and the inter-stage cooler through pipelines respectively.

[0012] Furthermore: The condenser is connected to the first pipeline. An air extraction valve on the B side of the condenser is installed on the first pipeline. An air extraction valve on the A side of the condenser is installed on the second pipeline. The second pipeline is connected to the first pipeline. A steam turbine vacuum breaking valve is installed on the third pipeline. The third pipeline is connected to the first pipeline.

[0013] Further: The first pipeline is divided into a fourth pipeline, a fifth pipeline, and a sixth pipeline. The fourth pipeline is sequentially connected to the manual valve at the inlet of the A vacuum pump, the check valve at the inlet of the A vacuum pump, the pneumatic valve at the inlet of the A vacuum pump, the A vacuum pump, and the A gas-water separator. The seventh pipeline is sequentially connected to the A orifice plate, the A vacuum pump cooler, and the A gas-water separator. The connection point of the seventh pipeline is between the pneumatic valve at the inlet of the A vacuum pump and the A vacuum pump. The eighth pipeline connects the A vacuum pump and the A vacuum pump cooler. The ninth pipeline connects the A gas-water separator, and an exhaust check valve of the A vacuum pump gas-water separator is installed on the ninth pipeline. The tenth pipeline is sequentially connected to the automatic water replenishing solenoid valve of the A vacuum pump gas-water separator, the water replenishing pressure reducing valve of the A vacuum pump gas-water separator, and the water supply valve from the condensate main pipe to the A vacuum pump. The eleventh pipeline connects the A gas-water separator, and the connection point is between the water replenishing pressure reducing valve of the A vacuum pump gas-water separator and the water supply valve from the condensate main pipe to the A vacuum pump. A water replenishing bypass valve of the A vacuum pump gas-water separator is installed on the eleventh pipeline. The A vacuum pump is connected to the twelfth pipeline, and a drain valve of the A vacuum pump pump body is installed on the twelfth pipeline. The A gas-water separator is connected to the thirteenth pipeline, and an overflow valve of the A vacuum pump gas-water separator is installed on the thirteenth pipeline. The A gas-water separator is connected to the fourteenth pipeline, and a drain valve of the A vacuum pump gas-water separator is installed on the fourteenth pipeline. The twelfth pipeline, the thirteenth pipeline, and the fourteenth pipeline converge into the fifteenth pipeline.

[0014] Further: The fifth pipeline is sequentially connected to the manual valve at the inlet of the B vacuum pump, the check valve at the inlet of the B vacuum pump, the pneumatic valve at the inlet of the B vacuum pump, the B vacuum pump, and the B gas-water separator. The sixteenth pipeline is sequentially connected to the B orifice plate, the B vacuum pump cooler, and the B gas-water separator. The connection point of the sixteenth pipeline is between the pneumatic valve at the inlet of the B vacuum pump and the B vacuum pump. The seventeenth pipeline connects the B vacuum pump and the B vacuum pump cooler. The eighteenth pipeline connects the B gas-water separator, and an exhaust check valve of the B vacuum pump gas-water separator is installed on the eighteenth pipeline. The nineteenth pipeline is sequentially connected to the manual bypass valve for water replenishing of the B gas-water separator, the water replenishing pressure reducing valve of the B vacuum pump gas-water separator, and the water supply valve from the condensate main pipe to the B vacuum pump. The nineteenth pipeline connects the B gas-water separator, and the connection point is between the water replenishing pressure reducing valve of the B vacuum pump gas-water separator and the water supply valve from the condensate main pipe to the B vacuum pump. An automatic water replenishing solenoid valve of the B vacuum pump gas-water separator is installed on the nineteenth pipeline. The B vacuum pump is connected to the twentieth pipeline, and a drain valve of the B vacuum pump pump body is installed on the twentieth pipeline. The B gas-water separator is connected to the twenty-first pipeline, and an overflow valve of the B vacuum pump gas-water separator is installed on the twenty-first pipeline. The B gas-water separator is connected to the twenty-second pipeline, and a drain valve of the B vacuum pump gas-water separator is installed on the twenty-second pipeline. The twentieth pipeline, the twenty-first pipeline, and the twenty-second pipeline converge into the twenty-third pipeline. The fifteenth pipeline and the twenty-third pipeline converge into the forty-second pipeline.

[0015] Further: The sixth pipeline is sequentially connected to the manual intake valve of the C vacuum pump, the pneumatic intake valve of the C vacuum pump, and the roots vacuum pump. The twenty-fourth pipeline is connected to the sixth pipeline, and the connection point is between the pneumatic intake valve of the C vacuum pump and the roots vacuum pump. The twenty-fourth pipeline is sequentially connected to the vacuum release solenoid valve of the C vacuum pump and the stop valve before the vacuum release solenoid valve of the C vacuum pump. The twenty-fifth pipeline is sequentially connected to the roots vacuum pump, the inter-stage cooler, the self-priming drain valve of the liquid ring pump of the C vacuum pump, the water ring vacuum pump, the cavitation protection door of the liquid ring vacuum pump of the C vacuum pump, the C gas-water separator, the stop valve after the automatic replenishing solenoid valve of the working fluid of the C vacuum pump, the automatic replenishing solenoid valve of the working fluid of the C vacuum pump, the stop valve before the automatic replenishing solenoid valve of the working fluid of the C vacuum pump, the pressure reducing valve, and the water replenishing door of the working fluid of the C vacuum pump. The twenty-sixth pipeline is connected to the roots vacuum pump and the inter-stage cooler. The twenty-seventh pipeline is sequentially connected to the check valve of the liquid ring pump of the C vacuum pump, the pneumatic intake valve of the liquid ring pump of the C vacuum pump, the water ring vacuum pump, and the C gas-water separator. The connection point of the twenty-seventh pipeline is between the roots vacuum pump and the inter-stage cooler. The twenty-eighth pipeline is connected to the inter-stage cooler and the cooling water outlet valve of the C vacuum pump. The twenty-ninth pipeline is connected to the roots vacuum pump, and the connection point is between the inter-stage cooler and the cooling water outlet valve of the C vacuum pump. The thirtieth pipeline is sequentially connected to the inter-stage cooler, the plate heat exchanger, the working fluid inlet valve of the liquid ring pump of the C vacuum pump, and the C gas-water separator. The thirty-first pipeline is connected to the roots vacuum pump and the cooling water valve of the C vacuum pump, and the connection point is between the inter-stage cooler and the plate heat exchanger. The thirty-second pipeline is connected to the water ring vacuum pump and the plate heat exchanger. The thirty-third pipeline is connected to the plate heat exchanger, the outlet door of the C filter for cooling water A, the inlet door of the C filter for cooling water A, and the inlet door of the cooling water of the C vacuum pump. The thirty-fourth pipeline is connected to the outlet door of the C filter for cooling water B and the inlet door of the C filter for cooling water B, and the connection points are between the plate heat exchanger and the outlet door of the C filter for cooling water A, and between the inlet door of the C filter for cooling water A and the inlet door of the cooling water of the C vacuum pump. The C gas-water separator is connected to the thirty-fifth pipeline, and a check valve for the exhaust of the liquid ring pump of the C vacuum pump is installed on the thirty-fifth pipeline. The thirty-sixth pipeline is connected to the C gas-water separator and the bypass door for replenishing the working fluid of the C vacuum pump, and the connection point is between the stop valve before the automatic replenishing solenoid valve of the working fluid of the C vacuum pump and the pressure reducing valve. The water ring vacuum pump is connected to the thirty-seventh pipeline and the thirty-eighth pipeline. A sewage discharge 1 valve for the liquid ring vacuum pump of the C vacuum pump is installed on the thirty-seventh pipeline, and a sewage discharge 2 valve for the liquid ring vacuum pump of the C vacuum pump is installed on the thirty-eighth pipeline. The thirty-seventh pipeline and the thirty-eighth pipeline converge into the thirty-ninth pipeline. The C gas-water separator is connected to the fortieth pipeline, and a sewage discharge door for the gas-liquid separator of the C vacuum pump is installed on the fortieth pipeline. The forty-first pipeline is sequentially connected to the inter-stage cooler, the sewage discharge door of the vacuum pump shell-and-tube heat exchanger, the connection point of the thirty-ninth pipeline, and the connection point of the fortieth pipeline.

[0016] The beneficial effects of the present utility model are as follows:

[0017] 1. The utility model is highly energy-efficient, has a high ultimate vacuum value, and saves cooling water volume.

[0018] 2. By replacing the equipment model, the air extraction capacity of the unit of the utility model is improved, the air extraction volume is increased, the vacuum degree in the condenser is effectively improved, thereby improving the thermal efficiency of the unit, further reducing the specific volume of steam, improving the operation efficiency of the steam turbine, and reducing fuel consumption.

[0019] 3. The utility model has low accessory cost, can reduce the maintenance workload and maintenance cost, reduce the equipment operation noise, and meets the environmental protection requirements.

[0020] 4. The working performance of the utility model is not restricted by the increase of the working water temperature, and at the same time, the problem of cavitation of the vacuum pump is solved, which helps to improve the stability of the vacuum degree of the unit in the high-temperature season. Brief Description of the Drawings

[0021] Figure 1 It is a schematic diagram of the utility model.

[0022] In the figure: 1 - Turbine vacuum breaker, 2 - Air extraction valve on the A side of the condenser, 3 - Air extraction valve on the B side of the condenser, 4 - Pneumatic valve at the inlet of Vacuum Pump A, 5 - Manual valve at the inlet of Vacuum Pump A, 6 - Check valve at the inlet of Vacuum Pump A, 7 - Drain valve of the pump body of Vacuum Pump A, 8 - Check valve for air and water separator exhaust of Vacuum Pump A, 9 - Drain valve of the air and water separator of Vacuum Pump A, 10 - Automatic water replenishment solenoid valve of the air and water separator of Vacuum Pump A, 11 - Bypass valve for water replenishment of the air and water separator of Vacuum Pump A, 12 - Pressure reducing valve for water replenishment of the air and water separator of Vacuum Pump A, 13 - Pneumatic valve at the inlet of Vacuum Pump B, 14 - Manual valve at the inlet of Vacuum Pump B, 15 - Drain valve of the pump body of Vacuum Pump B, 16 - Check valve for air and water separator exhaust of Vacuum Pump B, 17 - Drain valve of the air and water separator of Vacuum Pump B, 18 - Manual bypass valve for water replenishment of the air and water separator of Vacuum Pump B, 19 - Automatic water replenishment solenoid valve of the air and water separator of Vacuum Pump B, 20 - Pressure reducing valve for water replenishment of the air and water separator of Vacuum Pump B, 21 - Water supply valve from the condensate main pipe to Vacuum Pump A, 22 - Water supply valve from the condensate main pipe to Vacuum Pump B, 23 - Overflow valve of the air and water separator of Vacuum Pump A, 24 - Overflow valve of the air and water separator of Vacuum Pump B, 25 - Manual air inlet valve of Vacuum Pump C, 26 - Pneumatic air inlet valve of Vacuum Pump C, 27 - Check valve of the liquid ring pump of Vacuum Pump C, 28 - Pneumatic air inlet valve of the liquid ring pump of Vacuum Pump C, 29 - Check valve for exhaust of the liquid ring pump of Vacuum Pump C, 30 - Cooling water valve of Vacuum Pump C, 31 - Automatic liquid replenishment solenoid valve for the working fluid of Vacuum Pump C, 32 - Stop valve before the automatic liquid replenishment solenoid valve for the working fluid of Vacuum Pump C, 33 - Stop valve after the automatic liquid replenishment solenoid valve for the working fluid of Vacuum Pump C, 34 - Bypass valve for liquid replenishment of the working fluid of Vacuum Pump C, 35 - Drain valve of the air-liquid separator of Vacuum Pump C, 36 - Inlet valve of the working fluid of the liquid ring pump of Vacuum Pump C, 37 - First drain valve of the liquid ring vacuum pump of Vacuum Pump C, 38 - Second drain valve of the liquid ring vacuum pump of Vacuum Pump C, 39 - Drain valve of the shell-and-tube heat exchanger of the vacuum pump, 40 - Self-priming liquid discharge valve of the liquid ring pump of Vacuum Pump C, 41 - Inlet valve of Filter A for the cooling water of Vacuum Pump C, 42 - Outlet valve of Filter A for the cooling water of Vacuum Pump C, 43 - Inlet valve of Filter B for the cooling water of Vacuum Pump C, 44 - Outlet valve of Filter B for the cooling water of Vacuum Pump C, 45 - Stop valve before the vacuum release solenoid valve of Vacuum Pump C, 46 - Vacuum release solenoid valve of Vacuum Pump C, 47 - Cavitation protection valve of the liquid ring vacuum pump of Vacuum Pump C, 48 - Outlet valve of the cooling water of Vacuum Pump C, 49 - Inlet valve of the cooling water of Vacuum Pump C, 50 - Working fluid water supply valve of Vacuum Pump C, 51 - Check valve at the inlet of Vacuum Pump B, 52 - Orifice plate A, 53 - Orifice plate B, 54 - Pressure reducing valve, 55 - Condenser, 56 - Vacuum Pump A, 57 - Cooler of Vacuum Pump A, 58 - Air and water separator A, 59 - Vacuum Pump B, 60 - Cooler of Vacuum Pump B, 61 - Air and water separator B, 62 - Roots vacuum pump, 63 - Inter-stage cooler, 64 - Water ring vacuum pump, 65 - Plate heat exchanger, 66 - Air and water separator C. Detailed implementation mode

[0023] To enable those skilled in the art to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts shall fall within the scope of protection of this application.

[0024] It should be noted that the terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances for the embodiments of this application described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those clearly listed steps or units, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0025] In this application, the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "middle", "outer", "front", "rear", etc. is based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe this application and its embodiments, and are not used to limit that the indicated devices, elements or components must have a specific orientation or be constructed and operated in a specific orientation.

[0026] Moreover, in addition to being able to represent an orientation or positional relationship, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0027] In addition, the terms "arranged", "connected", "fixed" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there can also be internal communication between two devices, elements or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0028] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The following will detail this application with reference to the drawings and in combination with the embodiments.

[0029] The preferred embodiments of the present utility model will be described in detail below with reference to the accompanying drawings.

[0030] Embodiment: In combination with Figure 1 , a vacuum maintaining device for a condenser of a 300 MW unit, comprising: a condenser 55, a roots vacuum pump 62, an inter-stage cooler 63, a liquid ring vacuum pump 64, a plate heat exchanger 65, a gas-liquid separator, and a vacuum pump;

[0031] The pipeline where the condenser 55 is located is divided into three paths. The first path is connected to the first loop, and the first loop is sequentially and circularly connected to a vacuum pump A 56, a gas-liquid separator A 58, and a vacuum pump cooler A 57;

[0032] The second path is connected to the second loop, and the second loop is sequentially and circularly connected to a vacuum pump B 59, a vacuum pump cooler B 60, and a gas-liquid separator B 61;

[0033] The third path is sequentially connected to the roots vacuum pump 62 and the inter-stage cooler 63. The liquid ring vacuum pump 64, a gas-liquid separator C 66, and the plate heat exchanger 65 are sequentially and circularly connected to form a third loop. The liquid ring vacuum pump 64 is also respectively connected to the roots vacuum pump 62 and the inter-stage cooler 63 through pipelines.

[0034] More specifically: The condenser 55 is connected to a first pipeline, and an air extraction valve 3 on the B side of the condenser is installed on the first pipeline. An air extraction valve 2 on the A side of the condenser is installed on the second pipeline. The second pipeline is connected to the first pipeline. A steam turbine vacuum breaker 1 is installed on the third pipeline, and the third pipeline is connected to the first pipeline.

[0035] More specifically: the first pipeline is divided into a fourth pipeline, a fifth pipeline and a sixth pipeline. The fourth pipeline is sequentially connected to the manual valve 5 at the inlet of the A vacuum pump, the check valve 6 at the inlet of the A vacuum pump, the pneumatic valve 4 at the inlet of the A vacuum pump, the A vacuum pump 56, and the A gas-water separator 58. The seventh pipeline is sequentially connected to the A orifice plate 52, the A vacuum pump cooler 57, and the A gas-water separator 58. The connection point of the seventh pipeline is between the pneumatic valve 4 at the inlet of the A vacuum pump and the A vacuum pump 56. The eighth pipeline connects the A vacuum pump 56 and the A vacuum pump cooler 57. The ninth pipeline connects the A gas-water separator 58. An exhaust check valve 8 of the A vacuum pump gas-water separator is installed on the ninth pipeline. The tenth pipeline is sequentially connected to the automatic water replenishing solenoid valve 10 of the A vacuum pump gas-water separator, the water replenishing pressure reducing valve 12 of the A vacuum pump gas-water separator, and the condensate main pipe to the water replenishing valve 21 of the A vacuum pump. The eleventh pipeline connects the A gas-water separator 58. The connection point is between the water replenishing pressure reducing valve 12 of the A vacuum pump gas-water separator and the condensate main pipe to the water replenishing valve 21 of the A vacuum pump. A water replenishing bypass valve 11 of the A vacuum pump gas-water separator is installed on the eleventh pipeline. The A vacuum pump 56 is connected to the twelfth pipeline. An A vacuum pump pump body drain valve 7 is installed on the twelfth pipeline. The A gas-water separator 58 is connected to the thirteenth pipeline. An overflow valve 23 of the A vacuum pump gas-water separator is installed on the thirteenth pipeline. The A gas-water separator 58 is connected to the fourteenth pipeline. A drain valve 9 of the A vacuum pump gas-water separator is installed on the fourteenth pipeline. The twelfth pipeline, the thirteenth pipeline and the fourteenth pipeline converge into the fifteenth pipeline.

[0036] More specifically: The fifth pipeline is sequentially connected to the manual valve 14 at the inlet of the B vacuum pump, the check valve 51 at the inlet of the B vacuum pump, the pneumatic valve 13 at the inlet of the B vacuum pump, the B vacuum pump 59, and the B gas-water separator 61. The sixteenth pipeline is sequentially connected to the B orifice plate 53, the B vacuum pump cooler 60, and the B gas-water separator 61. The connection point of the sixteenth pipeline is between the pneumatic valve 13 at the inlet of the B vacuum pump and the B vacuum pump 59. The seventeenth pipeline connects the B vacuum pump 59 and the B vacuum pump cooler 60. The eighteenth pipeline connects the B gas-water separator 61, and a check valve 16 for exhausting gas and water from the B vacuum pump gas-water separator is installed on the eighteenth pipeline. The nineteenth pipeline is sequentially connected to the manual bypass valve 18 for replenishing water to the B gas-water separator, the pressure reducing valve 20 for replenishing water to the B vacuum pump gas-water separator, and the valve 22 for replenishing water from the condensate main pipe to the B vacuum pump. The nineteenth pipeline is connected to the B gas-water separator 61, and the connection point is between the pressure reducing valve 20 for replenishing water to the B vacuum pump gas-water separator and the valve 22 for replenishing water from the condensate main pipe to the B vacuum pump. An automatic water replenishing solenoid valve 19 for the B vacuum pump gas-water separator is installed on the nineteenth pipeline. The B vacuum pump 59 is connected to the twentieth pipeline, and a drain valve 15 for the B vacuum pump pump body is installed on the twentieth pipeline. The B gas-water separator 61 is connected to the twenty-first pipeline, and an overflow valve 24 for the B vacuum pump gas-water separator is installed on the twenty-first pipeline. The B gas-water separator 61 is connected to the twenty-second pipeline, and a drain valve 17 for the B vacuum pump gas-water separator is installed on the twenty-second pipeline. The twentieth pipeline, the twenty-first pipeline, and the twenty-second pipeline converge into the twenty-third pipeline. The fifteenth pipeline and the twenty-third pipeline converge into the forty-second pipeline.

[0037] More specifically: The sixth pipeline is successively connected to the manual intake valve 25 of the C vacuum pump, the pneumatic intake valve 26 of the C vacuum pump, and the Roots vacuum pump 62. The twenty-fourth pipeline is connected to the sixth pipeline, and the connection point is between the pneumatic intake valve 26 of the C vacuum pump and the Roots vacuum pump 62. The twenty-fourth pipeline is successively connected to the vacuum release solenoid valve 46 of the C vacuum pump and the stop valve 45 in front of the vacuum release solenoid valve of the C vacuum pump. The twenty-fifth pipeline is successively connected to the Roots vacuum pump 62, the inter-stage cooler 63, the self-priming drainage valve 40 of the liquid ring pump of the C vacuum pump, the water ring vacuum pump 64, the cavitation protection valve 47 of the liquid ring vacuum pump of the C vacuum pump, the C gas-water separator 66, the stop valve 33 behind the automatic replenishing solenoid valve of the working fluid of the C vacuum pump, the automatic replenishing solenoid valve 31 of the working fluid of the C vacuum pump, the stop valve 32 in front of the automatic replenishing solenoid valve of the working fluid of the C vacuum pump, the pressure reducing valve 54, and the water replenishing valve 50 of the working fluid of the C vacuum pump. The twenty-sixth pipeline is connected to the Roots vacuum pump 62 and the inter-stage cooler 63. The twenty-seventh pipeline is successively connected to the check valve 27 of the liquid ring pump of the C vacuum pump, the pneumatic intake valve 28 of the liquid ring pump of the C vacuum pump, the water ring vacuum pump 64, and the C gas-water separator 66. The connection point of the twenty-seventh pipeline is between the Roots vacuum pump 62 and the inter-stage cooler 63. The twenty-eighth pipeline is connected to the inter-stage cooler 63 and the cooling water outlet valve 48 of the C vacuum pump. The twenty-ninth pipeline is connected to the Roots vacuum pump 62, and the connection point is between the inter-stage cooler 63 and the cooling water outlet valve 48 of the C vacuum pump. The thirtieth pipeline is successively connected to the inter-stage cooler 63, the plate heat exchanger 65, the working fluid inlet valve 36 of the liquid ring pump of the C vacuum pump, and the C gas-water separator 66. The thirty-first pipeline is connected to the Roots vacuum pump 62 and the cooling water valve 30 of the C vacuum pump, and the connection point is between the inter-stage cooler 63 and the plate heat exchanger 65. The thirty-second pipeline is connected to the water ring vacuum pump 64 and the plate heat exchanger 65. The thirty-third pipeline is connected to the plate heat exchanger 65, the outlet valve 42 of the A filter of the cooling water of the C vacuum pump, the inlet valve 41 of the A filter of the cooling water of the C vacuum pump, and the inlet valve 49 of the cooling water of the C vacuum pump. The thirty-fourth pipeline is connected to the outlet valve 44 of the B filter of the cooling water of the C vacuum pump and the inlet valve 43 of the B filter of the cooling water of the C vacuum pump, and the connection point is between the plate heat exchanger 65 and the outlet valve 42 of the A filter of the cooling water of the C vacuum pump, and between the inlet valve 41 of the A filter of the cooling water of the C vacuum pump and the inlet valve 49 of the cooling water of the C vacuum pump. The C gas-water separator 66 is connected to the thirty-fifth pipeline, and a check valve 29 for the exhaust of the liquid ring pump of the C vacuum pump is installed on the thirty-fifth pipeline. The thirty-sixth pipeline is connected to the C gas-water separator 66 and the bypass valve 34 for replenishing the working fluid of the C vacuum pump, and the connection point is between the stop valve 32 in front of the automatic replenishing solenoid valve of the working fluid of the C vacuum pump and the pressure reducing valve 54. The water ring vacuum pump 64 is connected to the thirty-seventh pipeline and the thirty-eighth pipeline. A sewage discharge valve 37 for the liquid ring vacuum pump of the C vacuum pump is installed on the thirty-seventh pipeline, and a sewage discharge valve 38 for the liquid ring vacuum pump of the C vacuum pump is installed on the thirty-eighth pipeline. The thirty-seventh pipeline and the thirty-eighth pipeline converge into the thirty-ninth pipeline. The C gas-water separator 66 is connected to the fortieth pipeline, and a sewage discharge valve 35 for the gas-liquid separator of the C vacuum pump is installed on the fortieth pipeline.The forty-first pipeline is successively connected to the inter-stage cooler 63, the drain valve 39 of the vacuum pump shell-and-tube heat exchanger, the connection point of the thirty-ninth pipeline, and the connection point of the fortieth pipeline.

[0038] More specifically: The models of the vacuum pumps are two 2BW5353 and one 2BW6 high-efficiency vacuum pump.

[0039] More specifically: When starting the vacuum, two 2BW4353 vacuum pumps start and run; only one 2BW6 high-efficiency vacuum pump needs to run to maintain the vacuum state, and the other two are in standby.

[0040] More specifically: The current high-efficiency roots water-ring vacuum pump unit uses a ZJQL600 roots vacuum pump supporting a 2BE1202 water-ring vacuum pump. The motor power of the entire system is 44KW, of which the motor of the roots pump is 22KW and the motor of the water-ring pump is 22KW;

[0041] The ZJQL800 roots vacuum pump is a more efficient roots pump, and its motor power requirement is the same as that of the ZJQL600 (22KW). This means that without replacing the motor, the ZJQL600 can be directly replaced without additional power system adjustment. The motor power of the ZJQL800 roots vacuum pump matches the existing motor, ensuring seamless equipment upgrade without replacing the motor;

[0042] The ZJQL800 has high-efficient gas suction capacity and can achieve a larger gas extraction volume while maintaining the existing structure of the system.

[0043] More specifically: By replacing the ZJQL600 with the ZJQL800, the gas extraction capacity of the unit will be increased from 600L / S to 800L / S, an increase of 30% in the gas extraction volume, effectively improving the vacuum degree in the condenser, thereby increasing the thermal efficiency of the unit;

[0044] It is estimated that the vacuum degree will be increased by 0.3KPa, which can further reduce the specific volume of steam, improve the operating efficiency of the steam turbine, and reduce fuel consumption.

[0045] More specifically: The ZJQL800 is optimized in design, has higher operating stability and reliability, and reduces the failure rate and maintenance frequency;

[0046] The existing configuration of the water-ring vacuum pump has been verified to be able to operate stably while increasing the gas extraction volume, ensuring the long-term stability of the system.

[0047] More specifically: The installation dimensions of the ZJQL800 are different from those of the ZJQL600, and the connecting pipes and anchor bolts need to be modified.

[0048] More specifically: From April to September, the open water cooling will be changed to industrial water cooling.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it is still possible to modify the technical solutions described in the foregoing embodiments, or to equivalently replace some or all of the technical features thereof; as long as there is no structural conflict, the various features in the specific embodiments disclosed in the present application can be combined with each other in any way, and it will not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention.

[0050] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. The vacuum maintaining device for the condenser of a 300MW unit, characterized in that, The device includes: a condenser (55), a Roots vacuum pump (62), an inter-stage cooler (63), a water ring vacuum pump (64), a plate heat exchanger (65), a gas-liquid separator, and a vacuum pump; The pipeline where the condenser (55) is located is divided into three paths. The first path is connected to the first loop, and the first loop is sequentially and circularly connected to a vacuum pump A (56), a gas-liquid separator A (58), and a vacuum pump cooler A (57); The second path is connected to the second loop, and the second loop is sequentially and circularly connected to a vacuum pump B (59), a vacuum pump cooler B (60), and a gas-liquid separator B (61); The third path is sequentially connected to the Roots vacuum pump (62) and the inter-stage cooler (63). The water ring vacuum pump (64), a gas-liquid separator C (66), and the plate heat exchanger (65) are sequentially and circularly connected to form the third loop. The water ring vacuum pump (64) is also connected to the Roots vacuum pump (62) and the inter-stage cooler (63) respectively through pipelines.

2. The 300MW unit condenser vacuum maintenance device according to claim 1, characterized in that: The condenser (55) is connected to the first pipeline. An air extraction valve on the B side of the condenser (3) is installed on the first pipeline. An air extraction valve on the A side of the condenser (2) is installed on the second pipeline. The second pipeline is connected to the first pipeline. A steam turbine vacuum breaker (1) is installed on the third pipeline. The third pipeline is connected to the first pipeline.

3. The 300MW unit condenser vacuum maintenance device according to claim 2, characterized in that: The first pipeline is divided into a fourth pipeline, a fifth pipeline, and a sixth pipeline. The fourth pipeline is sequentially connected to a manual valve at the inlet of vacuum pump A (5), a check valve at the inlet of vacuum pump A (6), a pneumatic valve at the inlet of vacuum pump A (4), vacuum pump A (56), and gas-liquid separator A (58). The seventh pipeline is sequentially connected to an orifice plate A (52), vacuum pump cooler A (57), and gas-liquid separator A (58). The connection point of the seventh pipeline is between the pneumatic valve at the inlet of vacuum pump A (4) and vacuum pump A (56). The eighth pipeline is connected to vacuum pump A (56) and vacuum pump cooler A (57). The ninth pipeline is connected to gas-liquid separator A (58). An exhaust check valve for the gas-liquid separator of vacuum pump A (8) is installed on the ninth pipeline. The tenth pipeline is sequentially connected to an automatic water replenishing solenoid valve for the gas-liquid separator of vacuum pump A (10), a water replenishing pressure reducing valve for the gas-liquid separator of vacuum pump A (12), and a water supply valve from the condensate main pipe to vacuum pump A (21). The eleventh pipeline is connected to gas-liquid separator A (58). The connection point is between the water replenishing pressure reducing valve for the gas-liquid separator of vacuum pump A (12) and the water supply valve from the condensate main pipe to vacuum pump A (21). A bypass valve for water replenishment of the gas-liquid separator of vacuum pump A (11) is installed on the eleventh pipeline. Vacuum pump A (56) is connected to the twelfth pipeline. A drain valve for the pump body of vacuum pump A (7) is installed on the twelfth pipeline. Gas-liquid separator A (58) is connected to the thirteenth pipeline. An overflow valve for the gas-liquid separator of vacuum pump A (23) is installed on the thirteenth pipeline. Gas-liquid separator A (58) is connected to the fourteenth pipeline. A drain valve for the gas-liquid separator of vacuum pump A (9) is installed on the fourteenth pipeline. The twelfth pipeline, the thirteenth pipeline, and the fourteenth pipeline converge into the fifteenth pipeline.

4. The 300MW unit condenser vacuum maintenance device according to claim 3, characterized in that: The fifth pipeline is connected in sequence to the manual door (14) of the B vacuum pump inlet, the check valve (51) of the B vacuum pump inlet, the pneumatic door (13) of the B vacuum pump inlet, the B vacuum pump (59), and the B gas-water separator (61); the sixteenth pipeline is connected in sequence to the B throttling orifice plate (53), the B vacuum pump cooler (60), and the B gas-water separator (61); the connection point of the sixteenth pipeline is between the pneumatic door (13) of the B vacuum pump inlet and the B vacuum pump (59); the seventeenth pipeline is connected to the B vacuum pump (59) and the B vacuum pump cooler (60); the eighteenth pipeline is connected to the B gas-water separator (61); the B vacuum pump gas-water separator exhaust check valve (16) is installed on the eighteenth pipeline; the nineteenth pipeline is connected in sequence to the B gas-water separator water supply manual bypass door (18), the B vacuum pump gas-water separator water supply pressure reducing valve (20), the condensate mother pipe to the B vacuum pump The water supply gate (22) is connected to the B gas-water separator (61). The connection point is between the B vacuum pump gas-water separator water supply pressure reducing valve (20) and the condensate mother pipe to the B vacuum pump water supply gate (22). The B vacuum pump gas-water separator automatic water supply solenoid valve (19) is installed on the nineteenth pipeline. The B vacuum pump (59) is connected to the twentieth pipeline. The B vacuum pump pump body water discharge gate (15) is installed on the twentieth pipeline. The B gas-water separator (61) is connected to the twenty-first pipeline. The B vacuum pump gas-water separator overflow gate (24) is installed on the twenty-first pipeline. The B gas-water separator (61) is connected to the twenty-second pipeline. The B vacuum pump gas-water separator water discharge gate (17) is installed on the twenty-second pipeline. The twentieth pipeline, the twenty-first pipeline, and the twenty-second pipeline are combined into the twenty-third pipeline. The fifteenth pipeline and the twenty-third pipeline are combined into the forty-second pipeline.

5. The condenser vacuum maintenance device for a 300MW unit according to claim 3, characterized in that: The sixth pipeline is successively connected to the manual intake valve (25) of the C vacuum pump, the pneumatic intake valve (26) of the C vacuum pump, and the Roots vacuum pump (62). The twenty-fourth pipeline is connected to the sixth pipeline, and the connection point is between the pneumatic intake valve (26) of the C vacuum pump and the Roots vacuum pump (62). The twenty-fourth pipeline is successively connected to the vacuum release solenoid valve (46) of the C vacuum pump and the stop valve (45) in front of the vacuum release solenoid valve of the C vacuum pump. The twenty-fifth pipeline is successively connected to the Roots vacuum pump (62), the inter-stage cooler (63), the self-priming drain valve (40) of the liquid ring pump of the C vacuum pump, the water ring vacuum pump (64), the cavitation protection valve (47) of the liquid ring vacuum pump of the C vacuum pump, the C gas-water separator (66), the stop valve (33) behind the automatic replenishing solenoid valve of the working fluid of the C vacuum pump, the automatic replenishing solenoid valve (31) of the working fluid of the C vacuum pump, the stop valve (32) in front of the automatic replenishing solenoid valve of the working fluid of the C vacuum pump, the pressure reducing valve (54), and the water replenishing valve (50) of the working fluid of the C vacuum pump. The twenty-sixth pipeline is connected to the Roots vacuum pump (62) and the inter-stage cooler (63). The twenty-seventh pipeline is successively connected to the check valve (27) of the liquid ring pump of the C vacuum pump, the pneumatic intake valve (28) of the liquid ring pump of the C vacuum pump, the water ring vacuum pump (64), and the C gas-water separator (66). The connection point of the twenty-seventh pipeline is between the Roots vacuum pump (62) and the inter-stage cooler (63). The twenty-eighth pipeline is connected to the inter-stage cooler (63) and the cooling water outlet valve (48) of the C vacuum pump. The twenty-ninth pipeline is connected to the Roots vacuum pump (62), and the connection point is between the inter-stage cooler (63) and the cooling water outlet valve (48) of the C vacuum pump. The thirtieth pipeline is successively connected to the inter-stage cooler (63), the plate heat exchanger (65), the working fluid inlet valve (36) of the liquid ring pump of the C vacuum pump, and the C gas-water separator (66). The thirty-first pipeline is connected to the Roots vacuum pump (62) and the cooling water valve (30) of the C vacuum pump, and the connection point is between the inter-stage cooler (63) and the plate heat exchanger (65). The thirty-second pipeline is connected to the water ring vacuum pump (64) and the plate heat exchanger (65). The thirty-third pipeline is connected to the plate heat exchanger (65), the outlet valve (42) of the A filter of the cooling water of the C vacuum pump, the inlet valve (41) of the A filter of the cooling water of the C vacuum pump, and the inlet valve (49) of the cooling water of the C vacuum pump. The thirty-fourth pipeline is connected to the outlet valve (44) of the B filter of the cooling water of the C vacuum pump and the inlet valve (43) of the B filter of the cooling water of the C vacuum pump, and the connection points are between the plate heat exchanger (65) and the outlet valve (42) of the A filter of the cooling water of the C vacuum pump, and between the inlet valve (41) of the A filter of the cooling water of the C vacuum pump and the inlet valve (49) of the cooling water of the C vacuum pump. The C gas-water separator (66) is connected to the thirty-fifth pipeline, and the C vacuum pump liquid ring pump exhaust check valve (29) is installed on the thirty-fifth pipeline. The thirty-sixth pipeline is connected to the C gas-water separator (66) and the bypass valve (34) for replenishing the working fluid of the C vacuum pump, and the connection point is between the stop valve (32) in front of the automatic replenishing solenoid valve of the working fluid of the C vacuum pump and the pressure reducing valve (54). The water ring vacuum pump (64) is connected to the thirty-seventh pipeline and the thirty-eighth pipeline.A C vacuum pump liquid ring vacuum pump sewage discharge valve one (37) is installed on the thirty-seventh pipeline, and a C vacuum pump liquid ring vacuum pump sewage discharge valve two (38) is installed on the thirty-eighth pipeline. The thirty-seventh pipeline and the thirty-eighth pipeline converge into the thirty-ninth pipeline. The C gas-water separator (66) is connected to the fortieth pipeline, and a C vacuum pump gas-liquid separator sewage discharge valve (35) is installed on the fortieth pipeline. The forty-first pipeline is sequentially connected to the inter-stage cooler (63), the vacuum pump shell-and-tube heat exchanger sewage discharge valve (39), the connection point of the thirty-ninth pipeline, and the connection point of the fortieth pipeline.

Images