A configuration system for a condensate pump of a thermal power unit

Abstract

The utility model belongs to power plant technical field relates to a thermal power unit condensate pump configuration system, including first branch, second branch, third branch, recirculation branch, condensate regulating valve pipeline and condenser, the third branch with first branch second branch are in parallel, the third branch includes condensate pump water inlet, condensate pump water inlet filter screen, condensate pump, condensate pump outlet check valve and condensate pump outlet door, and condensate pump water inlet, condensate pump water inlet filter screen, condensate pump, condensate pump outlet check valve and condensate pump outlet door are in proper order series connection. In steam turbine 20% rated load working condition, the existence of third branch can reduce condensate pump recirculation branch loss and condensate regulating valve pipeline throttling loss on, thereby reducing the pump work consumption of condensate pump.

Description

Technical Field

[0001] This utility model relates to the field of power plant technology, and in particular to a condensate pump configuration system for thermal power units. Background Technology

[0002] Under the "3060" dual-carbon policy framework, my country has witnessed large-scale development of new energy sources (wind power, photovoltaics, etc.), with a rapid increase in the proportion of new energy and power generation. However, due to the influence of the environment and meteorology, wind power and photovoltaic new energy are intermittent and unstable power sources, easily causing frequent fluctuations in grid load. This inevitably places new demands on the peak-shaving capacity of coal-fired power units, which serve as the "ballast" of the power system. Various regions have successively introduced policies to encourage coal-fired power plants to further explore their peak-shaving capacity and carry out flexibility upgrades, improving the enthusiasm of coal-fired power units to participate in deep peak-shaving through paid peak-shaving auxiliary mechanisms. Achieving deep peak-shaving as soon as possible and improving the operational flexibility of units has become an inevitable means to enhance the market competitiveness of coal-fired power enterprises.

[0003] With the deep peak shaving of thermal power units, the operating load of the units is reduced to 20% of the rated load. Under this condition, the operating conditions of various auxiliary machines deviate significantly from the existing design conditions. For condensate pumps selected according to the rated operating conditions, the condensate flow rate is reduced to 20% of the rated flow rate under deep peak shaving conditions, and the system pressure required is about 20% of the rated load. Since the flow rate is generally 25%-30% lower than the minimum flow rate of the condensate pump, and due to the characteristics of the pump, the pump outlet pressure increases instead of decreasing. Therefore, under deep peak shaving conditions, the condensate pump operation requires both opening the recirculation valve and significantly throttling the condensate regulating valve, resulting in an extremely uneconomical operating condition, which increases the plant power consumption rate and system operating energy consumption. Utility Model Content

[0004] To address the aforementioned problems, this utility model discloses a condensate pump configuration system for thermal power units. The technical solution of this utility model is implemented as follows:

[0005] A condensate pump configuration system for a thermal power unit includes a first branch, a second branch, a third branch, a recirculation branch, a condensate regulating valve pipeline, and a condenser;

[0006] One end of the recirculation branch is connected to the condenser, and the other end is connected to the condensate regulating valve pipeline.

[0007] The composite branch formed by the parallel connection of the first branch and the second branch is connected at one end to the condenser and at the other end to the pipeline between the condensate regulating valve pipeline and the recirculation branch.

[0008] The third branch is connected in parallel with the first branch and the second branch;

[0009] The third branch includes a condensate pump inlet valve, a condensate pump inlet filter, a condensate pump, a condensate pump outlet check valve, and a condensate pump outlet valve.

[0010] The condensate pump inlet valve, condensate pump inlet filter, condensate pump, condensate pump outlet check valve, and condensate pump outlet valve are connected in series.

[0011] Preferably, the condensate pump is selected according to the flow rate and pressure of 20% of the turbine's rated load.

[0012] Preferably, it also includes a fourth branch;

[0013] The fourth branch and the third branch are connected in parallel;

[0014] The fourth branch has the same structure as the third branch.

[0015] Preferably, the recirculation branch includes a condensate pump recirculation inlet valve, a condensate pump recirculation valve, and a condensate pump recirculation outlet valve.

[0016] Preferably, the condensate regulating valve pipeline includes a condensate regulating valve inlet valve, a condensate regulating valve, and a condensate regulating valve outlet valve.

[0017] The advantages of this utility model are as follows:

[0018] 1. Under the condition of 20% rated load of steam turbine, the existence of the third branch can reduce the loss of the condensate pump recirculation branch and the throttling loss on the condensate regulating valve pipeline, thereby reducing the pump power consumption of the condensate pump.

[0019] 2. When the condensate pump in the first branch is operating at 20% of the turbine's rated load, its operating point has deviated significantly from its design point, resulting in reduced operating efficiency. This invention utilizes a condensate pump in the third branch, operating at a low flow rate as its design condition. Its operating condition is close to the design condition, thus placing it in the high-efficiency operating range and further reducing the pump power consumption of the condensate pump. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only one embodiment of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a structural diagram of the condensate pump configuration system for thermal power units using traditional technology;

[0022] Figure 2This is a structural diagram of the condensate pump configuration system for a thermal power unit according to an embodiment of the present utility model;

[0023] Figure 3 for Figure 2 The system architecture diagram shown is an optimized version of the embodiment.

[0024] The symbols in the above figures have the following meanings:

[0025] 1. First condensate pump inlet valve; 2. First condensate pump inlet filter; 3. First condensate pump; 4. First condensate pump outlet check valve; 5. First condensate pump outlet valve; 6. Second condensate pump inlet valve; 7. Second condensate pump inlet filter; 8. Second condensate pump; 9. Second condensate pump outlet check valve; 10. Second condensate pump outlet valve; 11. Condensate pump recirculation outlet valve; 12. Condensate pump recirculation valve; 13. Condensate pump recirculation inlet valve; 14. Condenser ; 15, Condensate regulating valve inlet valve; 16, Condensate regulating valve; 17, Condensate regulating valve outlet valve; 18, Third condensate pump inlet valve; 19, Third condensate pump inlet filter screen; 20, Third condensate pump; 21, Third condensate pump outlet check valve; 22, Third condensate pump outlet valve; 23, Fourth condensate pump inlet valve; 24, Fourth condensate pump inlet filter screen; 25, Fourth condensate pump; 26, Fourth condensate pump outlet check valve; 27, Fourth condensate pump outlet valve. Detailed Implementation

[0026] The embodiments of the present invention will be described in more detail below with reference to the examples and accompanying drawings. It should be noted that the embodiments of the present invention are not limited to these examples.

[0027] Example: A condensate pump configuration system for a thermal power unit, such as Figure 2 As shown, it includes the first branch, the second branch, the third branch, the recirculation branch, the condensate regulating valve pipeline and the condenser 14.

[0028] One end of the recirculation branch is connected to the condenser 14, and the other end is connected to the condensate regulating valve pipeline.

[0029] The composite branch formed by the parallel connection of the first and second branches is connected at one end to the condenser 14 and at the other end to the pipeline between the condensate regulating valve pipeline and the recirculation branch.

[0030] The first branch includes the first condensate pump inlet valve 1, the first condensate pump inlet filter 2, the first condensate pump 3, the first condensate pump outlet check valve 4, and the first condensate pump outlet valve 5.

[0031] The second branch includes the second condensate pump inlet valve 6, the second condensate pump inlet filter 7, the second condensate pump 8, the second condensate pump outlet check valve 9, and the second condensate pump outlet valve 10.

[0032] The third branch includes the third condensate pump inlet valve 18, the third condensate pump inlet filter 19, the third condensate pump 20, the third condensate pump outlet check valve 21, and the third condensate pump outlet valve 22.

[0033] The recirculation branch includes a condensate pump recirculation inlet valve 11, a condensate pump recirculation valve 12, and a condensate pump recirculation outlet valve 13. The condensate pump recirculation inlet valve 11, the condensate pump recirculation valve 12, and the condensate pump recirculation outlet valve 13 are connected in series.

[0034] The condensate regulating valve pipeline includes a condensate regulating valve inlet valve 15, a condensate regulating valve 16, and a condensate regulating valve outlet valve 17; the condensate regulating valve inlet valve 15, the condensate regulating valve 16, and the condensate regulating valve outlet valve 17 are connected in series.

[0035] The third branch road runs in parallel with the first and second branch roads.

[0036] In this embodiment, the first condensate pump inlet valve 1, the first condensate pump inlet filter 2, the first condensate pump 3, the first condensate pump outlet check valve 4, and the first condensate pump outlet valve 5 are connected in series.

[0037] The second condensate pump inlet valve 6, the second condensate pump inlet filter 7, the second condensate pump 8, the second condensate pump outlet check valve 9, and the second condensate pump outlet valve 10 are connected in series.

[0038] The third condensate pump inlet valve 18, the third condensate pump inlet filter 19, the third condensate pump 20, the third condensate pump outlet check valve 21, and the third condensate pump outlet valve 22 are connected in series.

[0039] Traditional thermal power unit condensate pump configuration system, such as Figure 1As shown (for a 1,000 MW unit), when operating below 40% rated load, especially at 20% rated load, the system resistance drops significantly due to the decrease in system flow. Therefore, after passing through the first or second branch, some condensate enters the condensate regulating valve pipeline, while the rest returns to the condenser 14 via the recirculation branch. However, this condensate flowing through the pump recirculation branch wastes the pump's power. Furthermore, due to the characteristics of the condensate pump, its outlet pressure is higher at low flow rates. Therefore, compared to rated operating conditions, the condensate regulating valve 16 on the condensate regulating valve pipeline will experience greater throttling losses. In this unit, the first condensate pump 3 is designed and selected according to 100% rated load, with a condensate flow rate of 2520t / h, a design outlet pressure of 3.3MPa, and a rated power of 3350kW. Under deep adjustment conditions (20% rated load conditions), the outlet pressure of the first condensate pump 3 is 3.8MPa, the outlet flow rate is 644t / h, the recirculation flow rate is 180t / h, the throttling pressure of the condensate pump regulating valve is about 3MPa, and the operating power of the condensate pump is about 1655kW.

[0040] To address the aforementioned recirculation branch loss issue, this embodiment adds a third branch. Unlike the first condensate pump 3, which is designed for 100% rated load, the third condensate pump 20 is designed for 20% rated load, meaning its flow rate and outlet pressure are both at 20% of the rated load. Below 20% rated load, condensate is delivered to the deaerator via the third branch and the condensate regulating valve pipeline. In deep-adjustment mode, the third condensate pump 20 is selected with a flow rate of 600 t / h (greater than the system's required flow rate of 644-180=464 t / h), an outlet pressure of 1 MPa, and a power of approximately 250 kW. This results in energy savings of nearly 1400 kW, demonstrating significant energy savings in deep-adjustment mode.

[0041] When operating below 20% of rated load, this embodiment not only eliminates the recirculation branch loss problem in the prior art, but also reduces the throttling loss on the condensate regulating valve pipeline.

[0042] In addition to being used in deep peak shaving conditions, this embodiment can also be used in conditions where the demand for condensate flow is low, such as during the initial stage of unit startup, and is particularly suitable for infrastructure units.

[0043] In some preferred embodiments, the condensate pump configuration system for thermal power units may further include a fourth branch. The fourth branch is connected in parallel with the third branch. The fourth branch includes a fourth condensate pump inlet valve 23, a fourth condensate pump inlet filter 24, a fourth condensate pump 25, a fourth condensate pump outlet check valve 26, and a fourth condensate pump outlet valve 27.

[0044] In practical applications, the third condensate pump 20 and the fourth condensate pump 25 are selected based on 20% of the rated load flow and pressure, respectively. The parallel operation of the two pumps can meet the 40% rated load operation requirements. Compared with the operation of the first condensate pump 3, the operating power of the third and fourth condensate pumps 25 in the 20-40% rated load range is significantly reduced.

[0045] It should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A condensate pump configuration system for a thermal power unit, comprising a first branch, a second branch, a recirculation branch, a condensate regulating valve pipeline, and a condenser; One end of the recirculation branch is connected to the condenser, and the other end is connected to the condensate regulating valve pipeline. The composite branch formed by the parallel connection of the first branch and the second branch is connected at one end to the condenser and at the other end to the pipeline between the condensate regulating valve pipeline and the recirculation branch. Its features are, It also includes the third branch road; The third branch is connected in parallel with the first branch and the second branch; The third branch includes a condensate pump inlet valve, a condensate pump inlet filter, a condensate pump, a condensate pump outlet check valve, and a condensate pump outlet valve. The condensate pump inlet valve, condensate pump inlet filter, condensate pump, condensate pump outlet check valve, and condensate pump outlet valve are connected in series.

2. The condensate pump configuration system for thermal power units according to claim 1, characterized in that, The condensate pump is selected based on the turbine's rated load flow and pressure of 20%.

3. The condensate pump configuration system for thermal power units according to claim 2, characterized in that, It also includes the fourth branch road; The fourth branch and the third branch are connected in parallel; The fourth branch has the same structure as the third branch.

4. The condensate pump configuration system for thermal power units according to claim 1, characterized in that, The recirculation branch includes a condensate pump recirculation inlet valve, a condensate pump recirculation valve, and a condensate pump recirculation outlet valve.

5. The condensate pump configuration system for thermal power units according to claim 1, characterized in that, The condensate regulating valve pipeline includes a condensate regulating valve inlet valve, a condensate regulating valve, and a condensate regulating valve outlet valve.

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