Heating system for cold start of boiler

Abstract

The utility model discloses a heating system for the cold start of boiler, including steam pocket, hearth, water-cooled wall, water-cooled wall header and deaerator, in the height direction of boiler, hearth, water-cooled wall and water-cooled wall header all are located below steam pocket, water-cooled wall is located at the periphery of hearth, water-cooled wall header is located below water-cooled wall, deaerator is located below water-cooled wall header, deaerator is located below water-cooled wall header, deaerator is located below water-cooled wall header, deaerator is located below water-cooled wall header. The water-cooled wall header is provided with an air inlet pipe connected with the deaerator and used for receiving steam output by the deaerator, and the steam enters the steam pocket after entering the water-cooled wall from the water-cooled wall header. Compared with the prior art, the heating system can heat the boiler when the boiler is started in the cold state, and the heating time of the boiler starting in the cold state is shortened.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of heating systems for boiler cold state start, belong to the energy optimization and heat exchange equipment field of thermal power plant. BACKGROUND

[0002] Prior art boiler before cold state start or ignition initial stage, the starting process is long, increase the fuel consumption of starting process, in addition, in ignition initial stage, due to the uneven distribution of heat generated by fuel combustion, part of heating surface can not get sufficient water flow cooling in time, cause local temperature to be too high, appear dry burning phenomenon, greatly reduce its service life and safety.

[0003] Therefore, it is necessary to improve the existing boiler heating system to solve the above problems. CONTENT OF UTILITY MODEL

[0004] To solve the above technical problems, the utility model provides a kind of heating systems for boiler cold state start, the heating system for boiler cold state start at least can solve one of the problems, such as long boiler starting time, high fuel consumption in starting stage and uneven heating.

[0005] The technical scheme of the utility model is:

[0006] A kind of heating systems for boiler cold state start, including steam pocket, hearth, water-cooled wall, water-cooled wall header and deaerator, in the height direction of the boiler, the hearth, the water-cooled wall and water-cooled wall header are all located below the steam pocket, and the water-cooled wall is located at the periphery of the hearth, the water-cooled wall header is located below the water-cooled wall, the water-cooled wall header is equipped with the gas inlet pipe connected with the deaerator, for receiving the steam output from the deaerator, the steam enters the steam pocket after entering the water-cooled wall from the water-cooled wall header.

[0007] As a further improvement of the utility model, the water-cooled wall header is also equipped with water inlet pipe independent of the gas inlet pipe, the water entering the water-cooled wall header from the water inlet pipe is configured to be able to enter the pipeline of the water-cooled wall.

[0008] As a further improvement of the utility model, the steam entering the water-cooled wall header from the gas inlet pipe is used to heat the water entering the water-cooled wall header from the water inlet pipe to form hot steam, and the hot steam rises along the center of the pipeline of the water-cooled wall to the steam pocket, and the cold water entering the pipeline of the water-cooled wall descends along the two sides of the pipeline of the water-cooled wall to the water-cooled wall header.

[0009] As a further improvement of the utility model, the gas inlet pipe is equipped with regulating valve, and the regulating valve is configured to be able to adjust the gas pressure of the steam output by the deaerator.

[0010] As a further improvement of the utility model, the air inlet pipe is further provided with an isolation valve between the water cooling wall header and the regulating valve, the isolation valve is provided with two, wherein the first isolation valve allows the steam output by the deaerator to enter the water cooling wall header, and the second isolation valve allows the water cooling wall header to discharge sewage.

[0011] As a further improvement of the utility model, the heating system comprises an expansion vessel connected with the water inlet pipe of the water cooling wall header, and the expansion vessel is configured to be capable of relieving the pressure of the water flow entering the water cooling wall header.

[0012] As a further improvement of the utility model, the water inlet pipe is provided with an isolation valve, and the isolation valve is provided with two, wherein the third isolation valve allows external water to enter the water cooling wall header, and the fourth isolation valve allows the water cooling wall header to discharge sewage.

[0013] As a further improvement of the utility model, the deaerator is provided with a gas conveying pipe connected with the air inlet pipe, and the gas conveying pipe is provided with a partition door, and the partition door is configured to be capable of selectively connecting the air inlet pipe with the gas conveying pipe.

[0014] As a further improvement of the utility model, the boiler is provided with at least two, and the air inlet pipes of the water cooling wall headers of the two boilers are connected with the same deaerator, and the steam output by the deaerator can be selectively input into the water cooling wall headers of the two boilers.

[0015] As a further improvement of the utility model, the water cooling wall header comprises an east water cooling wall header, a south water cooling wall header, a west water cooling wall header and a north water cooling wall header arranged outside the periphery of the furnace, and the steam output by the deaerator is synchronously input into the east water cooling wall header, the south water cooling wall header, the west water cooling wall header and the north water cooling wall header.

[0016] The utility model has the beneficial technical effects that: the air inlet pipe is arranged between the water cooling wall header and the deaerator, so that the steam output by the deaerator can directly heat the water cooling wall header, the heating time of the boiler is shortened, the fuel consumption during the starting stage is reduced, in addition, the steam of the deaerator is used instead of introducing new equipment, the full use of the existing energy is ensured, and energy waste is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is the structure block diagram of the heating system according to the preferred embodiment of the utility model.

[0018] Figure 2 It is Figure 1 It is the pipeline diagram among the water cooling wall header, the deaerator and the expansion vessel of the heating system shown in the figure.

[0019] Figure 3 is Figure 2 one of the boilers specific piping diagram.

[0020] Figure 4 is Figure 1 schematic diagram of the small circulation in the water wall of the boiler.

[0021] Reference signs:

[0022] heating system; 2 - steam drum; 3 - water wall; 4 - water wall header, 41 - air inlet pipe, 411 - regulating valve, 412 - isolation valve, 4121 - first isolation valve, 4122 - second isolation valve, 4123 - third isolation valve, 4124 - fourth isolation valve, 42 - water inlet pipe, 43 - expansion vessel, 44 - east water wall header, 45 - south water wall header, 46 - west water wall header, 47 - north water wall header; 5 - deaerator, 51 - air supply pipe, 511 - isolation door. DETAILED DESCRIPTION

[0023] In order to enable the technical means of the utility model to be more clearly understood, and to be implemented in accordance with the contents of the specification, the specific embodiments of the utility model will be described in further detail below in combination with the drawings and examples, and the following examples are used to illustrate the utility model, but are not used to limit the scope of the utility model.

[0024] Please refer to Figures 1 to 3 As shown in the figure, the utility model discloses a kind of heating system 1 for boiler cold state start, which can accelerate the time of first start of boiler, reduce the consumption of fuel in starting process, so that the first start of boiler changes from cold state start to warm state start, with practicality.

[0025] The boiler includes steam drum 2, furnace, water wall 3, water wall header 4 and deaerator 5, in the height direction of the boiler, the furnace, the water wall 3 and water wall header 4 are all located below the steam drum 2, and the water wall 3 is located at the outer periphery of the furnace, and the water wall header 4 is located below the water wall 3.

[0026] Generally speaking, the water wall header 4 collects the working medium (usually steam-water mixture) in the pipeline of water wall 3, or redistributes the working medium to other pipelines. Therefore, the water wall header 4 plays a role in collecting, mixing and distributing the working medium in the boiler to ensure uniform distribution and heating of the working medium, reduce thermal deviation, and improve the thermal efficiency and safety of the boiler.

[0027] The furnace is also provided with an economizer, and a feedwater pipe is correspondingly provided on the deaerator 5, which is used to supply the deaerated water to the economizer and then to the steam drum 2. The steam inlet pipe of the deaerator 5 receives steam from outside, which is used to treat the water stored in the deaerator 5. The water treated by the deaerator 5 is high-temperature water. When the boiler is started, the inner wall of the pipe is cold, and the high-temperature water can easily cause the pipe to break. Therefore, when the boiler is started, the water in the deaerator 5 cannot be directly transmitted to the steam drum 2.

[0028] The water wall header 4 is provided with an air inlet pipe 41 connected to the deaerator 5, which is used to receive the steam output from the deaerator 5. The steam enters the water wall 3 from the water wall header 4 and then enters the steam drum 2.

[0029] The deaerator 5 is provided with a gas delivery pipe 51 connected to the air inlet pipe 41, and the gas delivery pipe 51 is provided with a partition door 511, which is configured to selectively connect the gas delivery pipe 51 to the air inlet pipe 41. That is, by providing the partition door 511, the steam can be selectively output at a certain time, that is, the steam can be connected and output only when the boiler is started.

[0030] In this embodiment, the boiler is provided with at least two water wall headers 4, and the air inlet pipes 41 of the two water wall headers 4 are connected to the same deaerator 5. The steam output from the deaerator 5 can be selectively input into the water wall headers 4 of the two boilers. Preferably, the boiler is provided with six boilers, as shown in Figure 2 The amount of steam in the deaerator 5 and the existing demand are fully considered, of course, the number of boilers can be adjusted according to the actual demand, which is not limited. In this way, multiple boilers can be heated at the same time, greatly improving the heating efficiency of the boiler.

[0031] Specifically, as shown in Figure 3 The water wall header 4 includes an east water wall header 44, a south water wall header 45, a west water wall header 46, and a north water wall header 47 arranged outside the furnace. The steam output from the deaerator 5 is simultaneously input into the east water wall header 44, the south water wall header 45, the west water wall header 46, and the north water wall header 47. By simultaneously heating the east water wall header 44, the south water wall header 45, the west water wall header 46, and the north water wall header 47, the uniformity of heating is ensured.

[0032] Preferably, the water-cooled wall header 4 is provided with a bottom header, the gas inlet pipe 41 is arranged on the bottom header, and the bottom header is in communication with the east water-cooled wall header 44, the south water-cooled wall header 45, the west water-cooled wall header 46, and the north water-cooled wall header 47. By heating the bottom header, the east water-cooled wall header 44, the south water-cooled wall header 45, the west water-cooled wall header 46, and the north water-cooled wall header 47 can be heated simultaneously. In this way, the water-cooled wall headers 4 at all positions are heated synchronously, ensuring uniform heating.

[0033] The water-cooled wall header 4 is also provided with a water inlet pipe 42 independent of the gas inlet pipe 41. The water entering the water-cooled wall header 4 from the water inlet pipe 42 is configured to enter the pipes of the water-cooled wall 3. In this way, the pipes of the water-cooled wall header 4 or the water-cooled wall 3 are avoided from being in a dry-burning state with only steam. By synchronously introducing water and gas, this problem can be effectively solved, and the heating effect of the boiler is further improved.

[0034] Preferably, referring to Figure 4 As shown, the steam entering the water-cooled wall header 4 from the gas inlet pipe 41 is used to heat the water entering the water-cooled wall header 4 from the water inlet pipe 42 to form hot steam. The hot steam rises along the center of the pipes of the water-cooled wall 3 to the steam drum 2, and the cold water entering the pipes of the water-cooled wall 3 descends along the two sides of the pipes of the water-cooled wall 3 to the water-cooled wall header 4. In this way, a small water circulation is formed through the conversion between water and steam. Generally, the hot steam is a mixture of steam and water, rises along the center of the pipes to the steam drum 2, and is separated by the steam drum 2. The separated cold water flows back to the water-cooled wall header 4 through the downcomer, and the downcomer and the riser open the large circulation on both sides of the water-cooled wall 3 according to the conventional boiler structure. Therefore, in this embodiment, the boiler has two water circulations, i.e., the large circulation of the conventional downcomer and riser, and the small circulation in the pipes of the water-cooled wall 3 during the initial start-up process.

[0035] The gas inlet pipe 41 is provided with an adjusting valve 411 configured to adjust the gas pressure of the steam output by the deaerator 5. In this embodiment, the gas pressure of the steam output by the deaerator 5 is 1.6 MPa, which is not necessarily suitable for the water-cooled wall header 4. Therefore, the adjusting valve 411 is used to adjust the gas pressure of the steam to make it more suitable for subsequent use.

[0036] The air inlet pipe 41 is further provided with an isolation valve 412 between the water cooling wall header 4 and the regulating valve 411, the isolation valve 412 is provided with two, wherein the first isolation valve 4121 allows the steam output by the deaerator 5 to enter the water cooling wall header 4, and the second isolation valve 4122 allows the water cooling wall header 4 to discharge sewage.

[0037] In order to distinguish the two action areas, the first isolation valve 4121 is a low-pressure valve, because the steam output by the deaerator 5 is low-pressure steam, and the second isolation valve 4122 is a high-pressure valve, because normal sewage discharge requires a high-pressure pipeline.

[0038] The heating system 1 comprises an expansion vessel 43 connected with the water inlet pipe 42 of the water cooling wall header 4, and the expansion vessel 43 is configured to be able to relieve the pressure of the water flow entering the water cooling wall header 4.

[0039] The water inlet pipe 42 is provided with an isolation valve 412, the isolation valve 412 is provided with two, wherein the third isolation valve 4123 allows external water to enter the water cooling wall header 4, and the fourth isolation valve 4124 allows the water cooling wall header 4 to discharge sewage. In contrast, the water inlet pipe 42 is originally also a sewage discharge pipe, and here the two sewage discharge pipes are directly utilized, effectively solving the problem of cold-state heating of the boiler, and without additional cost.

[0040] In summary, the heating system 1 for the cold-state starting of the boiler of the utility model shortens the heating time of the boiler and reduces the fuel consumption in the starting stage by arranging the air inlet pipe 41 between the water cooling wall header 4 and the deaerator 5, so that the steam output by the deaerator 5 can directly heat the water cooling wall header 4, in addition, by using the steam of the deaerator 5, new equipment is not introduced again, the full use of existing energy is ensured, and energy waste is avoided.

[0041] The above only describes the preferred embodiments of the utility model, and is not used to limit the utility model, it should be pointed out that, for ordinary skilled people in the technical field, without departing from the technical principles of the utility model, a number of improvements and modifications can be made, and these improvements and modifications should be regarded as the protection scope of the utility model.

Claims

1. A heating system for cold start-up of a boiler, characterized in that The boiler comprises a drum (2), a furnace, a water-cooled wall (3), a water-cooled wall header (4) and a deaerator (5). In the height direction of the boiler, the furnace, the water-cooled wall (3) and the water-cooled wall header (4) are all below the drum (2), the water-cooled wall (3) is at the outer periphery of the furnace, the water-cooled wall header (4) is below the water-cooled wall (3), the water-cooled wall header (4) is provided with an air inlet pipe (41) connected with the deaerator (5) for receiving steam output from the deaerator (5), the steam enters the water-cooled wall (3) from the water-cooled wall header (4) and then enters the drum (2).

2. The heating system of claim 1, wherein, The water-cooled wall header (4) is further provided with a water inlet pipe (42) independent of the air inlet pipe (41), water entering the water-cooled wall header (4) from the water inlet pipe (42) is configured to enter the pipeline of the water-cooled wall (3).

3. The heating system of claim 2, wherein, Steam entering the water-cooled wall header (4) from the air inlet pipe (41) is used to heat water entering the water-cooled wall header (4) from the water inlet pipe (42) to form hot steam, the hot steam rises along the center of the pipeline of the water-cooled wall (3) to the drum (2), and cold water entering the pipeline of the water-cooled wall (3) descends along the two sides of the pipeline of the water-cooled wall (3) to the water-cooled wall header (4).

4. The heating system of claim 1, wherein, The air inlet pipe (41) is provided with a regulating valve (411) configured to adjust the air pressure of the steam output from the deaerator (5).

5. The heating system of claim 4, wherein, The air inlet pipe (41) is further provided with an isolation valve (412) between the water-cooled wall header (4) and the regulating valve (411), the isolation valve (412) has two, a first isolation valve (4121) allowing the steam output from the deaerator (5) to enter the water-cooled wall header (4), and a second isolation valve (4122) allowing the water-cooled wall header (4) to be drained.

6. The heating system of claim 2, wherein, The heating system (1) comprises an expansion vessel (43) connected with the water inlet pipe (42) of the water-cooled wall header (4), the expansion vessel (43) is configured to relieve the pressure of the water flow entering the water-cooled wall header (4).

7. The heating system of claim 6, wherein, The water inlet pipe (42) is provided with an isolation valve (412), the isolation valve (412) has two, a third isolation valve (4123) allowing external water to enter the water-cooled wall header (4), and a fourth isolation valve (4124) allowing the water-cooled wall header (4) to be drained.

8. The heating system of claim 1, wherein, The deaerator (5) is provided with a gas delivery pipe (51) connected with the air inlet pipe (41), the gas delivery pipe (51) is provided with a partition door (511) configured to allow the gas delivery pipe (51) to selectively communicate with the air inlet pipe (41).

9. The heating system of claim 1, wherein, The boiler is provided with at least two, the air inlet pipes (41) of the water-cooled wall headers (4) of the two boilers are connected to the same deaerator (5), and the steam output from the deaerator (5) can be selectively input into the water-cooled wall headers (4) of the two boilers.

10. The heating system of claim 1, wherein, The water-cooled wall header (4) comprises an east water-cooled wall header (44), a south water-cooled wall header (45), a west water-cooled wall header (46) and a north water-cooled wall header (47) arranged on the outer periphery of the furnace, and the steam output from the deaerator (5) is synchronously introduced into the east water-cooled wall header (44), the south water-cooled wall header (45), the west water-cooled wall header (46) and the north water-cooled wall header (47).

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