A power-saving control method for water filling of a steam drum boiler in a thermal power unit

Abstract

The present invention provides a power-saving control method for feed water filling of a steam drum boiler in a thermal power unit, belonging to the technical field of thermal power generation; it includes a first passage communicated with the water outlet of the deaerator. The first passage includes two connecting pipes, and a fixed inner pipe is fixedly sleeved in the connecting pipe. One end of the connecting pipe is fixedly connected with a first through pipe, and a stop valve is installed at the water inlet of the first through pipe and is communicated with the water outlet of the deaerator. The other end of the connecting pipe is fixedly connected with a second through pipe. By setting the fixed inner pipe, under the action of the natural high and low pressure difference, the feed water in the deaerator enters the steam drum through the first through pipe, the fixed inner pipe and the second through pipe. The working time of the motor-driven feed water pump and its booster pump is saved by making full use of the acting force of the high and low pressure difference to send the feed water into the steam drum. In this way, the production expenditure of the enterprise is reduced, the production efficiency of the enterprise is improved, and at the same time, the switching of the feed water pushing mode is fast, ensuring the feed water pushing efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal power generation, and particularly relates to a power-saving control method for the feed water supply of a steam drum boiler in a thermal power unit. Background Art

[0002] Before a coal-fired thermal power unit starts the ignition of the steam drum boiler, it is necessary to boost the feed water from the deaerator into the boiler steam drum through a feed water pump, and maintain the water level in the steam drum within a reasonable range for use in the initial stage of ignition startup.

[0003] The pumps used to provide the kinetic energy of the feed water are two pneumatic feed water pumps and one electric feed water pump. When the unit is operating normally, two 50% capacity pneumatic feed water pumps operate in parallel, and the other 50% capacity electric feed water pump is in standby.

[0004] Due to its excellent low-flow regulation performance, the electric feed water pump is used both during the feed water supply to the boiler and in the initial stage of ignition startup. The disadvantage is that the electric feed water pump consumes a large amount of electricity. Taking the electric feed water pump equipped with a Y900-2-4 type motor in a certain factory as an example, its power is 5500 kW. Calculated at a 50% load rate, the electricity cost per hour is more than two thousand yuan. For one startup of the unit, the feed water supply time for the boiler is generally 2 to 4 hours. Calculated based on 10 startups of the unit per year, the electricity consumption cost for a single unit to use the electric feed water pump for water supply during startup each year is about forty to eighty thousand yuan, which greatly increases the production cost of the enterprise. Therefore, the present application provides a power-saving control method for the feed water supply of a steam drum boiler in a thermal power unit to meet the requirements. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a power-saving control method for the feed water supply of a steam drum boiler in a thermal power unit to solve the problems of high power consumption and high electricity cost for a single startup of the existing thermal power unit, which increases the production cost of the enterprise.

[0006] To solve the above technical problems, the present invention provides the following technical solutions:

[0007] A power-saving control method for the feed water supply of a steam drum boiler in a thermal power unit sequentially includes the following steps in the order of the water supply process:

[0008] S1: Send the feed water into the steam drum through the pressure difference generated by the natural height difference between the deaerator and the steam drum, and do not start any water pump for boosting during this process;

[0009] S2: When the feed water cannot be continuously sent into the steam drum through the height difference, start the pneumatic feed water pump booster pump to continue the water supply until the boiler is ignited;

[0010] S3: When the boiler is ignited and the steam pressure in the steam drum starts to rise, when the head of the pneumatic feed water pump booster pump is insufficient to maintain the continuous water inlet of the steam drum, start the electric feed water pump and its booster pump to send the feed water into the steam drum until the feed water in the steam drum reaches the rated value.

[0011] It includes a first passage communicating with the water outlet of the deaerator. The first passage includes two connecting pipes, and a fixed inner pipe is fixedly sleeved inside the connecting pipes. One end of the connecting pipe is fixedly connected to a first through pipe. A stop valve is installed at the water inlet of the first through pipe and is communicated with the water outlet of the deaerator. The other end of the connecting pipe is fixedly connected to a second through pipe. A check valve is installed at the end of the second through pipe away from the connecting pipe and is communicated with the water inlet of the steam drum. The first through pipe, the fixed inner pipe, and the second through pipe are communicated with each other. A number of first through holes and a number of second through holes are provided on the fixed inner pipe. One side of the connecting pipe is communicated with a third through pipe, and the third through pipe is connected to the water inlet of the pneumatic feed water pump pre-pump; a guiding component for unidirectionally conducting the feed water is installed inside the fixed inner pipe, an adjusting component for opening and blocking the first through holes and the second through holes is installed on the fixed inner pipe, and a limiting component for driving the adjusting component to act is installed on the guiding component.

[0012] Preferably, the guiding component includes a first limiting frame fixedly installed inside the fixed inner pipe. A number of first limiting sleeves are annularly arrayed on one side of the first limiting frame. The first limiting sleeves penetrate through the first limiting frame. A movable rod that penetrates and extends outside the fixed inner pipe is slidably sleeved inside the first limiting sleeve. First limiting rods are fixedly installed at the ends of the movable rods away from each other. A same piston is slidably connected to the ends of the movable rods close to each other.

[0013] Preferably, the cross-section of the first limiting frame is a frustum-shaped member, the cross-section of the piston is a frustum-shaped member, the first limiting frame is adapted to the piston, a sealing ring is fixedly installed on the inclined surface of the piston, a sealing ring is fixedly installed inside the first limiting sleeve, and the movable rod is slidably sleeved with the sealing ring inside the first limiting sleeve.

[0014] Preferably, a number of first sliding grooves are annularly arrayed on one side of the piston. The first sliding grooves are T-shaped sliding grooves. Sliders are fixedly installed at one ends of the movable rods. The movable rods are slidably connected to the first sliding grooves through the sliders.

[0015] Preferably, the adjusting component includes a sliding pipe slidably sleeved on the fixed inner pipe. A number of third through holes and a number of fourth through holes are provided on the sliding pipe. A limiting plate is fixedly sleeved on the sliding pipe. A number of movable grooves are annularly arrayed on the sliding pipe. The movable rods are located inside the movable grooves.

[0016] Preferably, two sealing rings are fixedly sleeved on the fixed inner pipe, and both of the two sealing rings on the fixed inner pipe are located inside the sliding pipe.

[0017] Preferably, the limiting component includes a sliding ring slidably sleeved in the connecting pipe. A plurality of second limiting frames are fixedly installed on one side of the sliding ring in an annular array. The first limiting rod is slidably sleeved in the second limiting frame. A plurality of second limiting rods are fixedly installed on the other side of the sliding ring and penetrate and extend to one side of the limiting plate. The second limiting rod is slidably sleeved in the limiting plate. A limiting block is fixedly installed at one end of the second limiting rod away from the sliding ring. One side of the limiting block is fixedly connected to a spring sleeved on the second limiting rod. One end of the spring is fixedly connected to one side of the limiting plate.

[0018] Preferably, a plurality of first water passing holes are formed on one side of the sliding ring, and a plurality of second water passing holes are formed on one side of the limiting plate. The first water passing holes and the second water passing holes are coaxial.

[0019] Preferably, a water flow sensor is arranged in the third through pipe. The water flow sensor is signal-connected to the motor switch of the pneumatic feed water pump pre-pump. A three-way valve is fixedly installed at the water outlet of the pneumatic feed water pump pre-pump. One water outlet of the three-way valve is communicated with the water inlet of the steam pump. The other water outlet of the three-way valve is fixedly connected to a fourth through pipe. The fourth through pipe is communicated with the three-way valve. A check valve is installed at one end of the fourth through pipe away from the three-way valve and is communicated with the water inlet of the steam drum. A pressure sensor is installed at one end of the fourth through pipe away from the three-way valve. The pressure sensor is signal-connected to the motor switch of the electric feed water pump.

[0020] Compared with the prior art, the present invention has at least the following beneficial effects:

[0021] In the above solution, by setting the fixed inner pipe, under the action of the natural high and low pressure difference, the feed water in the deaerator enters the steam drum through the first through pipe, the fixed inner pipe, and the second through pipe, making full use of the acting force of the high and low pressure difference to send the feed water into the steam drum. By this method, the working load and working time of the electric feed water pump and its pre-pump are saved, the production expenditure of the enterprise is reduced, and the production efficiency of the enterprise is improved.

[0022] By setting the piston, the piston abuts against the first limiting frame under the water pressure in the connecting pipe and the second through pipe, preventing the feed water in the connecting pipe and the second through pipe from flowing back. At the same time, the piston also drives the sliding pipe to move synchronously through the limiting component, making the first through hole communicate with the third through hole and the second through hole communicate with the fourth through hole. Through the above structural design, the damage to the pipe wall caused by the water hammer effect is reduced, and the service life of the first through pipe, the fixed inner pipe, and the second through pipe is prolonged.

[0023] By setting a fixed inner tube, the moving piston pushes the second limit frame through the movable rod and the first limit rod to drive the sliding ring to slide along the inner wall of the connecting tube. The sliding ring causes the limit plate and the sliding tube to move synchronously through friction, so that the first through hole and the third through hole, the second through hole and the fourth through hole are connected. The water supply in the fixed inner tube and the second through pipe enters the pneumatic water supply pump pre-pump through the third through hole, the fourth through hole, the first water hole, the second water hole and the third through pipe, thereby avoiding an increase in the workload of the deaerator due to a large amount of water supply remaining in the second through pipe, ensuring the service life of the deaerator and making full use of the water supply.

[0024] By setting the movable groove, when the water supply in the fixed inner tube squeezes the inner edges of the third through hole and the fourth through hole and causes the sliding tube to slide, the sliding tube squeezes the spring through the limit plate, and limits the movement stroke of the limit plate through the limit block. By providing the movable groove, the sliding tube is prevented from interfering with the movable rod during movement, causing damage to the movable rod or the sliding tube, thereby ensuring the stability of the movable rod and the sliding tube.

[0025] By setting a water flow sensor, when feed water flows in the pneumatic feed water pump pre-pump, the water flow sensor works and makes the switch of the pneumatic feed water pump pre-pump actuated to start the pneumatic feed water pump pre-pump, and the feed water is delivered to the steam drum through the three-way valve and the fourth-way pipe by the pneumatic feed water pump pre-pump, and under the action of the feed water entering the pneumatic feed water pump pre-pump, the auxiliary impeller quickly enters the rated working frequency, so that when the feed water cannot be pushed into the steam drum through the natural high and low pressure difference, the feed water pushing mode can be quickly switched to ensure the feed water pushing efficiency, and when the pressure sensor detects that the steam pressure in the steam drum is greater than the rated value, the pressure sensor works and makes the motor of the electric feed water pump work, and then the feed water is pushed into the steam drum through the electric feed water pump.

[0026] By arranging a piston, a first slide groove, a slider, a movable rod, a first limit rod, a second limit frame, a sliding ring, a limit plate, a second limit rod and a limit block, when it is necessary to fix the inner tube to push the feed water into the second through pipe in one direction again, the piston drives the limit plate to move through the first slide groove, the slider, the movable rod, the first limit rod, the second limit frame, the sliding ring, the second limit rod and the limit block to release the connection between the first through hole and the third through hole, and the second through hole and the fourth through hole, and resets under the elastic force of the spring to ensure that the feed water in the deaerator can be stably pushed into the steam drum again through the natural high and low pressure difference. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated herein and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, further serve to explain the principles of the present disclosure and to enable those skilled in the relevant art to make and use the present disclosure.

[0028] Figure 1Schematic structural diagram of the power-saving control method for water filling of the steam drum boiler of a thermal power unit;

[0029] Figure 2 Schematic three-dimensional assembly structure diagram of the first through pipe, connecting pipe, second through pipe, third through pipe and the pre-pump of the pneumatic feed water pump for the power-saving control method of water filling of the steam drum boiler of a thermal power unit;

[0030] Figure 3 Schematic three-dimensional enlarged structure diagram of the partial cross-section of the first passage from the first perspective;

[0031] Figure 4 Schematic three-dimensional enlarged structure diagram of the partial cross-section of the first passage from the second perspective;

[0032] Figure 5 For Figure 4 Enlarged structure diagram at position A in

[0033] Figure 6 Schematic three-dimensional enlarged cross-sectional structure diagram of the connecting pipe;

[0034] Figure 7 Schematic three-dimensional enlarged cross-sectional structure diagram of the first limit frame;

[0035] Figure 8 Schematic three-dimensional enlarged structure diagram of the sliding pipe.

[0036] [Reference Signs]

[0037] 1. First through pipe; 2. Connecting pipe; 3. Second through pipe; 4. Third through pipe; 5. Pre-pump of pneumatic feed water pump; 6. Fixed inner pipe; 7. First limit frame; 8. First limit sleeve; 9. Movable rod; 10. Piston; 11. First sliding groove; 12. First limit rod; 13. Second limit frame; 14. Sliding ring; 15. Second limit rod; 16. Limit plate; 17. Limit block; 18. Spring; 19. Sliding pipe; 20. Movable groove; 21. First through hole; 22. Second through hole; 23. Third through hole; 24. Fourth through hole.

[0038] As shown in the figure, in order to clearly show the structure of the embodiments of the present invention, specific structures and devices are marked in the figure, but this is only for schematic purposes and is not intended to limit the present invention to this specific structure, device and environment. Those of ordinary skill in the art can adjust or modify these devices and environments according to specific needs, and the adjustments or modifications made are still included in the scope of the appended claims. Detailed Embodiments

[0039] The following will describe in detail a power-saving control method for water filling of a steam drum boiler in a thermal power unit provided by the present invention in conjunction with the accompanying drawings and specific embodiments. At the same time, it should be noted here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments. For some well-known technologies, those skilled in the art can also adopt other alternative methods for implementation; moreover, the accompanying drawings are only for more specifically describing the embodiments and are not intended to specifically limit the present invention.

[0040] It should be noted that in the specification, when referring to "an embodiment", "embodiments", "exemplary embodiments", "some embodiments", etc., it indicates that the described embodiments may include specific features, structures or characteristics, but not necessarily every embodiment includes such specific features, structures or characteristics. Additionally, when combining embodiments to describe specific features, structures or characteristics, implementing such features, structures or characteristics in combination with other embodiments (whether explicitly described or not) should be within the knowledge of those skilled in the relevant art.

[0041] Generally, terms can be understood at least in part from their use in the context. For example, at least in part depending on the context, the term "one or more" as used herein can be used to describe any feature, structure or characteristic in a singular sense, or can be used to describe a combination of features, structures or characteristics in a plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey a set of exclusive factors, but rather can alternatively, at least in part depending on the context, allow for the existence of other factors that may not be explicitly described.

[0042] As used herein, the term "nominal / nominally" refers to the desired or target value of a characteristic or parameter for a component or process operation set during the design phase of a production or manufacturing process, as well as a range of values above and / or below the expected value. The range of values may be due to minor variations in the manufacturing process or tolerances. As used herein, the term "about" indicates a value of a given quantity that can vary based on a particular technology node associated with the subject semiconductor device. Based on a particular technology node, the term "about" can indicate a value of a given quantity that varies, for example, within 5% - 15% of the value (e.g., ±5%, ±10% or ±15% of the value).

[0043] It can be understood that the meanings of "on...", "above...", and "over..." in the present disclosure should be interpreted in the broadest manner, such that "on..." not only means "directly on" something, but also includes the meaning of being "on" something with intervening features or layers therebetween, and "above..." or "over..." not only means "above" or "over" something, but also can include the meaning of being "above" or "over" something with no intervening features or layers therebetween.

[0044] In addition, spatial relative terms such as "under", "below", "lower part", "above", "upper part", etc. may be used in this text for convenience of description to describe the relationship between one element or feature and another or more elements or features, as shown in the accompanying drawings. The spatial relative terms are intended to cover different orientations in the use or operation of the device in addition to the orientation depicted in the drawings. The device may be oriented in other ways, and the spatial relative descriptive terms used herein may be similarly interpreted accordingly.

[0045] As Figure 1 shown, an embodiment of the present invention provides a power-saving control method for feeding water into the steam drum boiler of a thermal power unit, which sequentially includes the following steps according to the sequence of the water feeding process:

[0046] S1: Feed the feed water into the steam drum through the pressure difference generated by the natural height difference between the deaerator and the steam drum, and do not start any water pump for boosting pressure during this process.

[0047] S2: When the feed water cannot be continuously fed into the steam drum through the height difference, start the pneumatic feed water pump fore pump to continue feeding water until the boiler is ignited.

[0048] S3: When the boiler is ignited, the steam pressure in the steam drum starts to rise. When the head of the pneumatic feed water pump fore pump is insufficient to maintain the continuous water inlet of the steam drum, start the motor-driven feed water pump and its fore pump to feed the feed water into the steam drum until the feed water in the steam drum reaches the rated value.

[0049] As Figures 2-3 shown, it includes a first passage communicated with the water outlet of the deaerator. The first passage includes two connecting pipes 2. A fixed inner pipe 6 is fixedly sleeved in the connecting pipe 2. One end of the connecting pipe 2 is fixedly connected with a first through pipe 1. A stop valve is installed at the water inlet of the first through pipe 1 and is communicated with the water outlet of the deaerator. The other end of the connecting pipe 2 is fixedly connected with a second through pipe 3. A check valve is installed at the end of the second through pipe 3 far away from the connecting pipe 2 and is communicated with the water inlet of the steam drum. By setting the check valve, it is avoided that when the steam pressure in the steam drum is greater than the head in the second through pipe 3, the feed water in the steam drum flows back, resulting in abnormal operation of the steam drum. The first through pipe 1, the fixed inner pipe 6, and the second through pipe 3 are communicated with each other. A plurality of first through holes 21 and a plurality of second through holes 22 are opened on the fixed inner pipe 6. One side of the connecting pipe 2 is communicated with a third through pipe 4, and the third through pipe 4 is connected with the water inlet of the pneumatic feed water pump fore pump 5; a guiding component for unidirectional conduction of the feed water is installed in the fixed inner pipe 6. An adjusting component for opening and blocking the first through holes 21 and the second through holes 22 is installed on the fixed inner pipe 6. A limiting component for driving the adjusting component to act is installed on the guiding component.

[0050] As Figure 4 , Figure 5 , Figure 7As shown, in this embodiment, the diversion component includes a first limiting frame 7 fixedly installed in the fixed inner tube 6. A number of first limiting sleeves 8 are annularly arrayed on one side of the first limiting frame 7. The first limiting sleeves 8 penetrate through the first limiting frame 7. A movable rod 9 that penetrates and extends outside the fixed inner tube 6 is slidably sleeved in the first limiting sleeve 8. First limiting rods 12 are fixedly installed at the mutually remote ends of the plurality of movable rods 9. A same piston 10 is slidably connected to the mutually proximate ends of the plurality of movable rods 9. The cross-section of the first limiting frame 7 is a frustum-shaped member. The cross-section of the piston 10 is a frustum-shaped member. The first limiting frame 7 is adapted to the piston 10. A sealing ring is fixedly installed on the inclined surface of the piston 10. A sealing ring is fixedly installed in the first limiting sleeve 8 to prevent the feed water in the fixed inner tube 6 from overflowing outside the fixed inner tube 6 through the first limiting sleeve 8. The movable rod 9 is slidably sleeved with the sealing ring in the first limiting sleeve 8. A number of first sliding grooves 11 are annularly arrayed on one side of the piston 10. The first sliding grooves 11 are T-shaped sliding grooves. Sliders are fixedly installed at one ends of the plurality of movable rods 9. The movable rod 9 is slidably connected to the first sliding grooves 11 through the sliders.

[0051] Open the stop valve. Under the action of the natural high and low pressure difference, the feed water in the deaerator enters the steam drum through the first through pipe 1, the fixed inner tube 6, and the second through pipe 3. The acting force of the high and low pressure difference is fully utilized to send the feed water into the steam drum. In this way, the working load and working time of the motor-driven feed pump and its booster pump are saved, the production expenditure of the enterprise is reduced, and the production efficiency of the enterprise is improved.

[0052] The specific movement process is as follows: When the feed water passes through the fixed inner tube 6, it will squeeze the piston 10. The piston 10 drives the movable rod 9 to move under the limitation of the first limiting sleeve 8 through the sliding groove. The movable rod 9 drives the first limiting rod 12 to move until the piston 10 stops moving when it reaches the maximum movement stroke under the limitation of the first limiting rod 12.

[0053] As Figure 3 、 Figure 8 As shown, in this embodiment, the adjusting component includes a sliding tube 19 slidably sleeved on the fixed inner tube 6. A number of third through holes 23 and a number of fourth through holes 24 are provided on the sliding tube 19. A limiting plate 16 is fixedly sleeved on the sliding tube 19. A number of movable grooves 20 are annularly arrayed on the sliding tube 19. The movable rod 9 is located in the movable grooves 20.

[0054] When the feed water can no longer be fed into the steam drum through the natural height difference in pressure, under the action of the water pressure in the steam drum, the check valve at one end of the second connecting pipe 3 operates to prevent the feed water in the steam drum from flowing back. The piston 10 abuts against the first limit frame 7 under the water pressure in the connecting pipe 2 and the second connecting pipe 3, preventing the feed water in the connecting pipe 2 and the second connecting pipe 3 from flowing back. At the same time, the piston 10 also drives the sliding pipe 19 to move synchronously through the limiting member. When the piston 10 abuts against the first limit frame 7, the first through hole 21 communicates with the third through hole 23, and the second through hole 22 communicates with the fourth through hole 24. At the same time, along with the operation of the check valve and the piston 10, the feed water in the first connecting pipe 1, the connecting pipe 2, and the second connecting pipe 3 is suddenly cut off, and a water hammer effect occurs under the action of the inertia of the feed water. Under the action of the force generated by the water hammer effect, the feed water squeezes the inner edges of the third through hole 23 and the fourth through hole 24, so that the communication areas between the first through hole 21 and the third through hole 23, and between the second through hole 22 and the fourth through hole 24 are further increased until the axes of the first through hole 21 and the third through hole 23, and the second through hole 22 and the fourth through hole 24 overlap, and the communication area reaches the maximum. At this time, the feed water in the first connecting pipe 1 and the fixed inner pipe 6 flows into the pneumatic feed water pump fore pump 5 through the first through hole 21 and the third through hole 23 via the first connecting pipe 1 and the third connecting pipe 4, and the feed water in the second connecting pipe 3 and the fixed inner pipe 6 flows into the first connecting pipe 1 through the second through hole 22 and the fourth through hole 24. Through the above structural design, the damage to the pipe wall caused by the water hammer effect is reduced, and the service lives of the first connecting pipe 1, the fixed inner pipe 6, and the second connecting pipe 3 are prolonged.

[0055] As Figures 3-6 shown, in this embodiment, two sealing rings are fixedly sleeved on the fixed inner pipe 6, and both of the two sealing rings on the fixed inner pipe 6 are located inside the sliding pipe 19, preventing the feed water from leaking through the first through hole 21, the second through hole 22, and the gap between the fixed inner pipe 6 and the sliding pipe 19 when passing through the fixed inner pipe 6, and ensuring the feed water pressure entering the steam drum through the second connecting pipe 3 under the natural height difference in pressure.

[0056] As Figure 3 、 Figure 5 shown, in this embodiment, the limiting member includes a sliding ring 14 slidably sleeved in the connecting pipe 2. A plurality of second limit frames 13 are fixedly installed on one side of the sliding ring 14 in an annular array. The first limit rod 12 is slidably sleeved in the second limit frame 13. A plurality of second limit rods 15 are fixedly installed on the other side of the sliding ring 14 and penetrate and extend to one side of the limit plate 16. The second limit rods 15 are slidably sleeved in the limit plate 16. A limit block 17 is fixedly installed at the end of the second limit rod 15 away from the sliding ring 14. A spring 18 sleeved on the second limit rod 15 is fixedly connected to one side of the limit block 17, and one end of the spring 18 is fixedly connected to one side of the limit plate 16; a plurality of first water through holes are formed in one side of the sliding ring 14, and a plurality of second water through holes are formed in one side of the limit plate 16, and the first water through holes and the second water through holes are coaxial.

[0057] The moving piston 10 pushes the second limit frame 13 through the movable rod 9 and the first limit rod 12, driving the sliding ring 14 to slide along the inner wall of the connecting pipe 2. The sliding ring 14 causes the limit plate 16 and the sliding pipe 19 to move synchronously through friction, thereby making the first through hole 21 and the third through hole 23, the second through hole 22 and the fourth through hole 24 communicate with each other, and the feed water in the fixed inner tube 6 and the second through pipe 3 enters the pneumatic water pump pre-pump 5 through the third through hole 23, the fourth through hole 24, the first water hole, the second water hole, and the third through pipe 4, thereby avoiding the increase of the workload of the deaerator due to the large amount of feed water remaining in the second through pipe 3, ensuring the service life of the deaerator, and making full use of the feed water.

[0058] When the water supply in the fixed inner tube 6 squeezes the inner edges of the third through hole 23 and the fourth through hole 24 and causes the sliding tube 19 to slide, the sliding tube 19 squeezes the spring 18 through the limit plate 16, and limits the movement stroke of the limit plate 16 through the limit block 17. By providing the movable groove 20, the sliding tube 19 is prevented from interfering with the movable rod 9 during movement, causing damage to the movable rod 9 or the sliding tube 19, thereby ensuring the stability of the movable rod 9 and the sliding tube 19.

[0059] like Figures 2-4 As shown, in the present embodiment, a water flow sensor is arranged in the third through pipe 4, and the water flow sensor is connected with the motor switch signal of the pneumatic water supply pump pre-pump 5, and a three-way valve is fixedly installed at the water outlet of the pneumatic water supply pump pre-pump 5, and one of the water outlets of the three-way valve is connected with the water inlet of the steam-driven pump, and the other water outlet of the three-way valve is fixedly connected with a fourth through pipe (not shown in the figure), and the fourth through pipe (not shown in the figure) is connected with the three-way valve, and a one-way valve is installed at one end of the fourth through pipe (not shown in the figure) away from the three-way valve and is connected with the water inlet of the steam drum, and a pressure sensor is installed at one end of the fourth through pipe away from the three-way valve, and the pressure sensor is connected with the motor switch signal of the electric water supply pump.

[0060] When feed water flows in the pneumatic feed water pump pre-pump 5, the water flow sensor works and causes the switch of the pneumatic feed water pump pre-pump 5 to start the pneumatic feed water pump pre-pump 5, and the feed water is delivered to the steam drum through the three-way valve and the fourth through pipe through the pneumatic feed water pump pre-pump 5. Under the action of the feed water entering the pneumatic feed water pump pre-pump 5, the auxiliary impeller quickly enters the rated working frequency, and then when the feed water cannot be pushed into the steam drum through the natural high and low pressure difference, the feed water pushing mode can be quickly switched to ensure the feed water pushing efficiency. When the pressure sensor detects that the steam pressure in the steam drum is greater than the rated value, the pressure sensor works and causes the motor of the electric feed water pump to work, and then the feed water is pushed into the steam drum through the electric feed water pump. The way in which the electric feed water pump pushes feed water into the steam drum is a prior art and is not elaborated here.

[0061] By setting the piston 10, the first chute 11, the slider, the movable rod 9, the first limiting rod 12, the second limiting frame 13, the sliding ring 14, the limiting plate 16, the second limiting rod 15, and the limiting block 17, when it is necessary to fix the inner pipe 6 and push water into the second through pipe 3 unidirectionally again, the piston 10 drives the limiting plate 16 to move through the first chute 11, the slider, the movable rod 9, the first limiting rod 12, the second limiting frame 13, the sliding ring 14, the second limiting rod 15, and the limiting block 17, so as to release the communication between the first through hole 21 and the third through hole 23, and between the second through hole 22 and the fourth through hole 24, and reset under the elastic force of the spring 18, so as to ensure that the feed water in the deaerator can be stably pushed into the steam drum again under the action of the natural height difference pressure.

[0062] The technical solution provided by the present invention is that by setting the fixed inner pipe and opening the stop valve, under the action of the natural height difference pressure, the feed water in the deaerator enters the steam drum through the first through pipe, the fixed inner pipe, and the second through pipe, making full use of the acting force of the height difference pressure to send the feed water into the steam drum. By this method, the working load and working time of the motor-driven feed pump and its pre-pump are saved, the production expenditure of the enterprise is reduced, and the production efficiency of the enterprise is improved; the specific movement process is as follows: when the feed water passes through the fixed inner pipe, it will squeeze the piston, and the piston drives the movable rod to move under the limitation of the first limiting sleeve through the chute, and the movable rod drives the first limiting rod to move until the piston stops moving when it reaches the maximum movement stroke under the limitation of the first limiting rod.

[0063] By setting the piston, when the feed water can no longer be sent into the steam drum through the natural height difference pressure, under the action of the water pressure in the steam drum, the check valve at one end of the second through pipe acts to prevent the feed water in the steam drum from flowing back. The piston abuts against the first limiting frame under the water pressure of the feed water in the connecting pipe and the second through pipe, preventing the feed water in the connecting pipe and the second through pipe from flowing back. At the same time, the piston also drives the sliding pipe to move synchronously through the limiting component. When the piston abuts against the first limiting frame, the first through hole communicates with the third through hole, and the second through hole communicates with the fourth through hole. At the same time, along with the actions of the check valve and the piston, the feed water in the first through pipe, the connecting pipe, and the second through pipe is suddenly cut off, and a water hammer effect occurs under the action of the inertia of the feed water. Under the action of the force generated by the water hammer effect, the feed water squeezes the inner edges of the third through hole and the fourth through hole, so as to further increase the communication area between the first through hole and the third through hole, and between the second through hole and the fourth through hole, until the axes of the first through hole and the third through hole, and the second through hole and the fourth through hole overlap, and the communication area reaches the maximum. At this time, the feed water in the first through pipe and the fixed inner pipe flows into the pre-pump of the pneumatic feed pump through the first through hole and the third through hole via the first through pipe and the third through pipe, and the feed water in the second through pipe and the fixed inner pipe flows into the first through pipe through the second through hole and the fourth through hole. Through the above structural design, the damage to the pipe wall caused by the water hammer effect is reduced, and the service life of the first through pipe, the fixed inner pipe, and the second through pipe is extended.

[0064] By setting a fixed inner tube, the moving piston pushes the second limit frame through the movable rod and the first limit rod to drive the sliding ring to slide along the inner wall of the connecting tube. The sliding ring causes the limit plate and the sliding tube to move synchronously through friction, so that the first through hole and the third through hole, the second through hole and the fourth through hole are connected. The water supply in the fixed inner tube and the second through pipe enters the pneumatic water supply pump pre-pump through the third through hole, the fourth through hole, the first water hole, the second water hole and the third through pipe, thereby avoiding an increase in the workload of the deaerator due to a large amount of water supply remaining in the second through pipe, ensuring the service life of the deaerator and making full use of the water supply.

[0065] By setting the movable groove, when the water supply in the fixed inner tube squeezes the inner edges of the third through hole and the fourth through hole and causes the sliding tube to slide, the sliding tube squeezes the spring through the limit plate, and limits the movement stroke of the limit plate through the limit block. By providing the movable groove, the sliding tube is prevented from interfering with the movable rod during movement, causing damage to the movable rod or the sliding tube, thereby ensuring the stability of the movable rod and the sliding tube.

[0066] By setting a water flow sensor, when feed water flows in the pneumatic feed water pump pre-pump, the water flow sensor works and makes the switch of the pneumatic feed water pump pre-pump actuated to start the pneumatic feed water pump pre-pump, and the feed water is delivered to the steam drum through the three-way valve and the fourth-way pipe through the pneumatic feed water pump pre-pump, and under the action of the feed water entering the pneumatic feed water pump pre-pump, the auxiliary impeller quickly enters the rated working frequency, so that when the feed water cannot be pushed into the steam drum through the natural high and low pressure difference, the feed water pushing mode can be quickly switched to ensure the feed water pushing efficiency, and when the pressure sensor detects that the steam pressure in the steam drum is greater than the rated value, the pressure sensor works and makes the motor of the electric feed water pump work, and then the feed water is pushed into the steam drum through the electric feed water pump. The way in which the electric feed water pump pushes feed water into the steam drum is the existing technology and is not elaborated here.

[0067] By arranging a piston, a first slide groove, a slider, a movable rod, a first limit rod, a second limit frame, a sliding ring, a limit plate, a second limit rod and a limit block, when it is necessary to fix the inner tube to push the feed water into the second through pipe in one direction again, the piston drives the limit plate to move through the first slide groove, the slider, the movable rod, the first limit rod, the second limit frame, the sliding ring, the second limit rod and the limit block to release the connection between the first through hole and the third through hole, and the second through hole and the fourth through hole, and resets under the elastic force of the spring to ensure that the feed water in the deaerator can be stably pushed into the steam drum again through the natural high and low pressure difference.

[0068] The present invention covers any alternatives, modifications, equivalent methods and solutions made within the spirit and scope of the present invention. For the public to have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention. However, those skilled in the art can fully understand the present invention even without the description of these details. Additionally, well-known methods, processes, procedures, components and circuits, etc. are not described in detail to avoid unnecessary confusion to the essence of the present invention.

[0069] Those of ordinary skill in the art can understand that all or part of the steps in implementing the above-described embodiment methods can be completed by instructing relevant hardware through a program, and this program can be stored in a computer-readable storage medium, such as: ROM / RAM, magnetic disk, optical disk, etc.

[0070] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A power-saving control method for water filling of a steam drum boiler in a thermal power unit, characterized in that, it sequentially includes the following steps according to the sequence of the water filling process: S1: Send the feed water into the steam drum through the pressure difference generated by the natural height difference between the deaerator and the steam drum, and do not start any water pumps to boost the pressure during this process; S2: When the feed water cannot be continuously sent into the steam drum through the height difference, start the pneumatic feed water pump fore pump to continue water filling until the boiler is ignited; S3: When the boiler is ignited, the steam pressure in the steam drum begins to rise. When the head of the pneumatic feed water pump fore pump is insufficient to maintain the continuous water inlet of the steam drum, start the motor-driven feed water pump and its fore pump to send the feed water into the steam drum until the feed water in the steam drum reaches the rated value; The steam drum boiler of the thermal power unit includes a first passage communicated with the water outlet of the deaerator. The first passage includes two connecting pipes. A fixed inner pipe is fixedly sleeved in the connecting pipe. One end of the connecting pipe is fixedly connected with a first through pipe. A stop valve is installed at the water inlet of the first through pipe and is communicated with the water outlet of the deaerator. The other end of the connecting pipe is fixedly connected with a second through pipe. A one-way valve is installed at the end of the second through pipe away from the connecting pipe and is communicated with the water inlet of the steam drum. The first through pipe, the fixed inner pipe, and the second through pipe are communicated with each other. A plurality of first through holes and a plurality of second through holes are formed in the fixed inner pipe. One side of the connecting pipe is communicated with a third through pipe. The third through pipe is connected with the water inlet of the pneumatic feed water pump fore pump; A guiding component for unidirectional conduction of the feed water is installed in the fixed inner pipe. An adjusting component for opening and blocking the first through hole and the second through hole is installed on the fixed inner pipe. A limiting component for driving the adjusting component to act is installed on the guiding component.

2. The power-saving control method for water filling of a steam drum boiler in a thermal power unit according to claim 1, characterized in that, the guiding component includes a first limiting frame fixedly installed in the fixed inner pipe. A plurality of first limiting sleeves are annularly arranged on one side of the first limiting frame. The first limiting sleeves penetrate through the first limiting frame. A movable rod that penetrates and extends outside the fixed inner pipe is slidably sleeved in the first limiting sleeve. First limiting rods are fixedly installed at the mutually remote ends of the plurality of movable rods. The mutually close ends of the plurality of movable rods are all slidably connected to the same piston.

3. The power-saving control method for water filling of a steam drum boiler in a thermal power unit according to claim 2, characterized in that, the cross section of the first limiting frame is a trapezoidal component, the cross section of the piston is a trapezoidal component, the first limiting frame is adapted to the piston, a sealing ring is fixedly installed on the inclined surface of the piston, a sealing ring is fixedly installed in the first limiting sleeve, and the movable rod is slidably sleeved with the sealing ring in the first limiting sleeve.

4. The power-saving control method for water filling of a steam drum boiler in a thermal power unit according to claim 2, characterized in that, a plurality of first sliding grooves are annularly arranged on one side of the piston. The first sliding grooves are T-shaped sliding grooves. Sliding blocks are fixedly installed at one ends of the plurality of movable rods. The movable rod is slidably connected with the first sliding groove through the sliding block.

5. The water filling power-saving control method for the steam drum boiler of a thermal power unit according to claim 2, characterized in that, the adjusting component includes a sliding tube slidably sleeved on the fixed inner tube, several third through holes and several fourth through holes are formed in the sliding tube, a limiting plate is fixedly sleeved on the sliding tube, several moving grooves are formed in the sliding tube in an annular array, and the moving rod is located in the moving groove.

6. The water filling power-saving control method for the steam drum boiler of a thermal power unit according to claim 5, characterized in that, two sealing rings are fixedly sleeved on the fixed inner tube, and both of the two sealing rings on the fixed inner tube are located inside the sliding tube.

7. The water filling power-saving control method for the steam drum boiler of a thermal power unit according to claim 5, characterized in that, the limiting component includes a sliding ring slidably sleeved in the connecting tube, several second limiting frames are fixedly installed on one side of the sliding ring in an annular array, the first limiting rod is slidably sleeved with the second limiting frame, several second limiting rods are fixedly installed on the other side of the sliding ring and penetrate and extend to one side of the limiting plate, the second limiting rod is slidably sleeved with the limiting plate, a limiting block is fixedly installed at one end of the second limiting rod away from the sliding ring, a spring sleeved on the second limiting rod is fixedly connected to one side of the limiting block, and one end of the spring is fixedly connected to one side of the limiting plate.

8. The water filling power-saving control method for the steam drum boiler of a thermal power unit according to claim 7, characterized in that, several first water passing holes are formed on one side of the sliding ring, several second water passing holes are formed on one side of the limiting plate, and the first water passing holes and the second water passing holes are coaxial.

9. The water filling power-saving control method for the steam drum boiler of a thermal power unit according to claim 1, characterized in that, a water flow sensor is arranged in the third through pipe, the water flow sensor is signal-connected to the motor switch of the pneumatic feed water pump pre-pump, a three-way valve is fixedly installed at the water outlet of the pneumatic feed water pump pre-pump, one water outlet of the three-way valve is communicated with the water inlet of the steam-driven pump, the other water outlet of the three-way valve is fixedly connected with a fourth through pipe, the fourth through pipe is communicated with the three-way valve, a one-way valve is installed at one end of the fourth through pipe away from the three-way valve and is communicated with the water inlet of the steam drum, a pressure sensor is installed at one end of the fourth through pipe away from the three-way valve, and the pressure sensor is signal-connected to the motor switch of the electric feed water pump.

Images