Condenser water replenishing and deoxidizing system applied to steam turbine unit after heat supply transformation

Abstract

The invention discloses a condenser water replenishing and deoxidizing system applied to a steam turbine unit after heat supply transformation, which comprises a condenser body, a condenser water replenishing and deoxidizing device is mounted in the condenser body, and a water replenishing pipeline, a water replenishing and heating steam pipeline and a temperature reducing water pipeline are arranged outside the condenser body. A water replenishing pipeline regulating valve group and a water replenishing flow measuring device are arranged on the water replenishing pipeline. According to the condenser water supplementing and deoxidizing system applied to the steam turbine unit after heat supply transformation, a water supplementing and spraying mode is adopted for deoxidizing, the contact area of supplemented water and heating steam is increased, the deoxidizing effect can be improved, the steam flow of the heating steam of the deoxidizing device can be adjusted according to the specific steam extraction flow and the water supplementing flow under various working conditions of a steam turbine generator, and the deoxidizing effect is improved. The water supplementing flow and the oxygen content of the condenser can be accurately controlled, the operation safety of a unit can be further improved, the deoxygenation effect meets the oxygen content requirement of safe operation of condensed water, the service life of each low-pressure heater is prolonged, and therefore the safety of the unit is improved.

Description

Technical Field

[0001] The invention relates to the technical field of condenser water replenishment and deoxidation for steam turbine unit heating transformation, in particular to a condenser water replenishment and deoxidation system applied to steam turbine unit heating transformation. Background Art

[0002] After the steam turbine generator set is transformed for heating, the steam extraction volume of the steam turbine increases significantly, and the steam extraction drain is not recycled. At this time, the condensate flow rate in the steam turbine heat recovery system drops sharply. A large amount of desalted water needs to be added to the condensate to ensure the normal operation of the system. Due to the increase in the amount of make-up water, the original steam turbine exhaust steam deoxygenation method can no longer meet the requirements of condenser make-up water deoxygenation due to the reduction of exhaust steam flow under heating conditions. It is necessary to find other ways to solve the problem of excessive oxygen content in the deaerator make-up water. For this reason, we propose a condenser make-up water deoxygenation system applied to steam turbine units after heating transformation. Summary of the invention

[0003] The purpose of the present invention is to address the deficiencies of the prior art and provide a condenser water makeup and deoxygenation system for use in a steam turbine unit after heating transformation, so as to solve the problems raised in the background technology.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a condenser feed water and deoxygenation system applied to a steam turbine unit after heating transformation, comprising a condenser body, a condenser feed water and deoxygenation device installed in the condenser body, a feed water pipeline, a feed water heating steam pipeline and a cooling water pipeline are arranged outside the condenser body, a feed water pipeline regulating valve group and a feed water flow measuring device are arranged on the feed water pipeline, a heating steam pipeline flow measuring device, a heating steam pipeline electric shut-off valve and a heating steam pipeline regulating valve are arranged on the feed water heating steam pipeline, and a cooling water flow measuring device and a cooling regulating valve group are arranged on the cooling water pipeline.

[0005] As a preferred technical solution of the present invention, the water supply pipeline regulating valve group arranged on the water supply pipeline is composed of a water supply pipeline shut-off valve, a water supply regulating valve and a water supply pipeline bypass electric shut-off valve.

[0006] As a preferred technical solution of the present invention, the water supply pipeline bypass electric shut-off valve is a spare valve.

[0007] As a preferred technical solution of the present invention, a desuperheater is connected to the feed water heating steam pipeline, and the desuperheater is connected to the steam side interface of the condenser feed water deoxygenation device.

[0008] As a preferred technical solution of the present invention, the cooling regulating valve group arranged on the cooling water pipeline includes a regulating valve and a cooling water pipeline shut-off valve, and the cooling water pipeline is connected to the desuperheater after passing through the regulating valve or the cooling water pipeline shut-off valve.

[0009] As a preferred technical solution of the present invention, the regulating valve 15 controls the flow rate of cooling water for the desuperheater, and can adjust the cooling water volume to ensure that the temperature of the heating steam is within the range allowed by the condenser or the exhaust device.

[0010] Compared with the prior art, the present invention provides a condenser water supply and deoxygenation system applied to a steam turbine unit after heating transformation, which has the following beneficial effects:

[0011] 1. This condenser water supply and deoxygenation system applied to the steam turbine unit after heating transformation can meet the water supply and deoxygenation requirements of the unit under extraction steam working condition. After the heating transformation, under the extraction steam working condition of the unit, the condenser water supply device is arranged in the condenser body, and deoxygenation is carried out by water supply spraying, which increases the contact area between the water supply and the heating steam, and can improve the deoxygenation effect. The flow area of ​​the water side of the deoxygenation device can be designed according to the water supply flow rate, and the water supply and deoxygenation system pipeline is provided with a regulating valve and a flow measurement device, which can meet the condenser water supply flow rate requirements under various working conditions;

[0012] 2. This condenser water supply and deaeration system applied to the steam turbine unit after heating transformation can improve the unit operation flexibility, can adjust the heating steam flow of the deaerator according to the specific extraction flow and water supply flow under various working conditions of the steam turbine generator, can accurately control the condenser water supply flow and oxygen content, can switch the operating conditions according to the user or unit operation needs, and increase the flexibility of the unit operation;

[0013] 3. This condenser feed water deoxygenation system applied to the heating transformation of the steam turbine unit can further increase the safety of the unit operation. The original condenser feed water deoxygenation uses the unit's exhaust steam to heat the feed water. As the extraction steam flow rate continues to increase, the feed water flow rate also needs to increase. However, as the extraction steam flow rate increases, the turbine exhaust steam flow rate decreases accordingly. At this time, the unit exhaust steam cannot process the condensate oxygen content to the indicator required for the safe operation of the unit. The oxygen content of the condensate increases, which accelerates oxygen corrosion, affects the service life of the low-pressure heater, and affects the safety of the unit.

[0014] 4. This condenser feed water deoxygenation system is used in the steam turbine unit after the heating transformation. It can use the external steam source to heat and deoxygenate the feed water, and can fully mix the feed water with the connected heating steam. The deoxygenation effect meets the oxygen content requirement for the safe operation of the condensate, prolongs the service life of each low-pressure heater, and thus improves the safety of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the condenser water feed and deoxygenation system of the present invention.

[0016] Drawings: 1. Condenser body; 2. Condenser feed water and deoxygenation device; 3. Feed water pipeline; 4. Feed water flow measuring device; 5. Feed water pipeline shut-off valve; 6. Feed water regulating valve; 7. Feed water pipeline bypass electric shut-off valve; 8. Feed water heating steam pipeline; 9. Heating steam pipeline flow measuring device; 10. Heating steam pipeline electric shut-off valve; 11. Heating steam pipeline regulating valve; 12. Desuperheater; 13. Desuperheating water pipeline; 14. Desuperheating water flow measuring device; 15. Regulating valve; 16. Desuperheating water pipeline shut-off valve. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] See also Figure 1 In this embodiment: a condenser water supply and deoxygenation system applied to a steam turbine unit after heating transformation, comprising a condenser body 1, a condenser water supply and deoxygenation device 2 is installed in the condenser body 1, a water supply pipeline 3 and a water supply heating steam pipeline 8 and a cooling water pipeline 13 are arranged outside the condenser body 1, a water supply pipeline regulating valve group and a water supply flow measuring device 4 are arranged on the water supply pipeline 3, the water supply pipeline 3 can be drawn from the water supply main pipe of the power plant, through the water supply flow measuring device 4, and then through the water supply pipeline regulating valve group (composed of a feed water pipeline shut-off valve 5, a feed water regulating valve 6 and a feed water pipeline bypass electric shut-off valve 7) enters the condenser feed water deoxygenation device 2, and the feed water heating steam pipeline 8 is provided with a heating steam pipeline flow measuring device 9, a heating steam pipeline electric shut-off valve 10 and a heating steam pipeline regulating valve 11. The heating steam pipeline regulating valve 11 controls the flow of heating steam used for different feed water amounts under various steam extraction conditions, and the cooling water pipeline 13 is provided with a cooling water flow measuring device 14 and a cooling regulating valve group.

[0019] In this embodiment, the feed water pipeline regulating valve group arranged on the feed water pipeline 3 is composed of a feed water pipeline shut-off valve 5, a feed water regulating valve 6 and a feed water pipeline bypass electric shut-off valve 7. The feed water pipeline bypass electric shut-off valve 7 is a spare valve. A desuperheater 12 is connected to the feed water heating steam pipeline 8. The desuperheater 12 is connected to the steam side interface of the condenser feed water deoxygenation device 2 to heat and deoxygenate the feed water of the condenser body 1. The cooling regulating valve group arranged on the cooling water pipeline 13 includes a regulating valve 15 and a cooling water pipeline shut-off valve 16. The cooling water pipeline 13 is connected to the desuperheater 12 after passing through the regulating valve 15 or the cooling water pipeline shut-off valve 16. The regulating valve 15 controls the flow rate of cooling water used by the desuperheater 12, and can adjust the cooling water volume to ensure that the temperature of the heating steam is within the range allowed by the condenser or the exhaust device.

[0020] Working principle and use process of the present invention: First part water supply pipeline 3: under the steam extraction condition of the unit, the newly added water supply pipeline 3 is started, the newly added water supply pipeline 3 is led out from the water supply main pipe of the power plant, passes through the water supply flow measurement device 4, and then passes through the water supply pipeline regulating valve group (composed of the water supply pipeline shut-off valve 5, the water supply regulating valve 6 and the water supply pipeline bypass electric shut-off valve 7) to enter the condenser water supply deoxygenation device 2, the condenser water supply deoxygenation device 2 is installed in the condenser body 1, under the steam extraction condition of the unit, the water supply pipeline shut-off valve 5 and the water supply regulating valve 6 are opened, and the water supply pipeline bypass electric shut-off valve 7 is a spare valve;

[0021] The second part is the water supply heating steam pipeline 8: the water supply heating steam pipeline 8 of the condenser body 1 is started under the extraction condition of the unit. The water supply heating steam pipeline 8 is led out from a certain extraction pipeline of the power plant that meets the conditions through the heating steam pipeline flow measurement device 9, the heating steam pipeline electric shut-off valve 10 and the heating steam pipeline regulating valve 11. It enters the desuperheater 12 for desuperheating and is connected to the steam side interface of the condenser water supply deoxygenation device 2 to heat and deoxygenate the water supply of the condenser body 1. The heating steam pipeline regulating valve 11 controls the flow of heating steam used for different water supply amounts under various extraction conditions, so that the oxygen content of condensate meets the standard requirements;

[0022] The third part is the cooling water pipeline 13: The cooling water pipeline 13 is led out from the condensate pipeline of the power plant, and enters the desuperheater 12 after passing through the cooling water flow measuring device 14 and the cooling regulating valve group (composed of a regulating valve 15 and a cooling water pipeline shut-off valve 16). By controlling the regulating valve 15, the cooling water volume is adjusted to ensure that the temperature of the heating steam is within the range allowed by the condenser or exhaust device.

[0023] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A condenser water replenishment and deoxygenation system applied to a steam turbine unit after heating transformation, comprising a condenser body (1), characterized in that: A condenser water supply and deoxygenation device (2) is installed in the condenser body (1); a water supply pipeline (3), a water supply heating steam pipeline (8) and a cooling water pipeline (13) are arranged outside the condenser body (1); a water supply pipeline regulating valve group and a water supply flow measurement device (4) are arranged on the water supply pipeline (3); a heating steam pipeline flow measurement device (9), a heating steam pipeline electric shut-off valve (10) and a heating steam pipeline regulating valve (11) are arranged on the water supply heating steam pipeline (8); and a cooling water flow measurement device (14) and a cooling regulating valve group are arranged on the cooling water pipeline (13).

2. The condenser water supply and deoxygenation system applied to the steam turbine unit after heating transformation according to claim 1, characterized in that: The water supply pipeline regulating valve group arranged on the water supply pipeline (3) is composed of a water supply pipeline shut-off valve (5), a water supply regulating valve (6) and a water supply pipeline bypass electric shut-off valve (7).

3. The condenser water supply and deoxygenation system applied to the steam turbine unit after heating transformation according to claim 1, characterized in that: The water supply pipeline bypass electric shut-off valve (7) is a spare valve.

4. The condenser water supply and deoxygenation system applied to the steam turbine unit after heating transformation according to claim 1 is characterized in that: The feed water heating steam pipeline (8) is connected to a desuperheater (12), and the desuperheater (12) is connected to the steam side interface of the condenser feed water deoxygenation device (2).

5. The condenser water supply and deoxygenation system applied to the steam turbine unit after heating transformation according to claim 1, characterized in that: The cooling regulating valve group arranged on the cooling water pipeline (13) comprises a regulating valve (15) and a cooling water pipeline shut-off valve (16); the cooling water pipeline (13) is connected to the desuperheater (12) after passing through the regulating valve (15) or the cooling water pipeline shut-off valve (16).

6. The condenser water supply and deoxygenation system applied to the steam turbine unit after heating transformation according to claim 1, characterized in that: The regulating valve 15 controls the flow rate of cooling water used by the desuperheater (12), and can adjust the cooling water volume to ensure that the temperature of the heating steam is within the range allowed by the condenser or the exhaust device.

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