A tower boiler unit ash and drainage system

Abstract

The utility model provides a kind of tower boiler unit ash removal and drainage system, comprising: with the ash removal device of air preheater hopper switching connection, for cleaning ash in air preheater hopper;With the drainage device of air preheater hopper switching connection, for discharging the wastewater of cleaning air preheater;First pipeline connected with multiple ash removal device;Second pipeline connected with multiple drainage device;When multiple ash removal device ash conveying, multiple ash removal device discharges the ash deposit in air preheater hopper by the first pipeline;When cleaning air preheater, multiple drainage device discharges the wastewater of cleaning air preheater by the second pipeline.The scheme of the utility model realizes the timely cleaning of air preheater outlet flue ash deposit of depth peak-shaving unit low load condition, reduces air preheater outlet flue ash deposit load.

Description

Technical Field

[0001] This utility model relates to the field of ash removal technology for tower boiler units, and in particular to an ash removal and drainage system for tower boiler units. Background Technology

[0002] Under the transformation of the energy structure, deep peak shaving of thermal power units has become an inevitable trend to ensure grid stability and promote the consumption of new energy. Especially for large-capacity tower boiler units, conventional designs do not include ash hoppers in the boiler body, and all flue gas fly ash is collected by dust collectors. However, under the low-load conditions of deep peak shaving, the flue gas velocity decreases, leading to severe ash accumulation in the horizontal flue gas duct at the air preheater outlet (especially at bends). This not only greatly increases the output burden of subsequent dust collectors, but more importantly, the continuously accumulating ash load can crack the flue gas duct welds, causing the flue gas duct to detach and posing a serious safety hazard. Therefore, it is urgent to solve the problem of the inability to clean the ash accumulation in the air preheater outlet flue gas duct of deep peak shaving units under low-load conditions, resulting in excessive ash load in the air preheater outlet flue gas duct. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a ash removal and drainage system for tower boiler units, which solves the problem that the ash accumulation in the air preheater outlet flue of deep peak-shaving units cannot be cleaned under low load conditions, resulting in excessive ash load in the air preheater outlet flue.

[0004] To solve the above-mentioned technical problems, the technical solution of this invention is as follows: A dust removal device that is switched and connected to the air preheater ash hopper is used to clean the ash in the air preheater ash hopper; A drainage device that is switched to the air preheater ash hopper is used to discharge wastewater from cleaning the air preheater; A first conduit connecting multiple of the aforementioned dust removal devices; A second pipe connecting multiple of the aforementioned drainage devices; When multiple ash removal devices are conveying ash, the multiple ash removal devices discharge the accumulated ash in the air preheater ash hopper through the first pipe; When the air preheater is being cleaned, multiple drainage devices discharge the wastewater from the air preheater through the second pipe.

[0005] Optionally, the dust removal device includes: The ash conveying pipeline connected to the ash hopper of the air preheater; The silo pump connected to the ash conveying pipeline; A mixer connected to the silo pump, the mixer being connected to the first pipeline; The ash in the air preheater ash hopper is transported to the silo pump through the ash conveying pipeline. The silo pump then ejects the ash into the mixer, where it is mixed with compressed air. The compressed air then transports the ash to the slag silo through the first pipeline.

[0006] Optionally, an inspection door and a pneumatic rotary feed valve are sequentially installed on the ash conveying pipeline along the direction of ash output; When the ash accumulation in the air preheater ash hopper reaches a preset height, the inspection door is opened to allow the ash in the air preheater ash hopper to fall into the ash conveying pipeline, and the pneumatic rotary feed valve is opened to allow the ash to fall into the silo pump.

[0007] Optionally, the ash conveying pipeline is also provided with an expansion joint, which is located between the inspection door and the pneumatic rotary feed valve.

[0008] Optionally, the drainage device includes: a hose and an electrically operated gate valve connected to the hose; When cleaning the air preheater, the ash conveying pipeline is disconnected, the hose is connected to the ash hopper of the air preheater, the electric gate valve is opened, and the wastewater from cleaning the air preheater is discharged to the industrial wastewater pipeline in the plant area.

[0009] Optionally, the air preheater ash hopper is equipped with a level gauge to detect whether the ash in the air preheater ash hopper has reached a preset height.

[0010] Optionally, the mixer is connected in series with the first pipe.

[0011] Optionally, the air preheater ash hopper is located at the bend of the horizontal flue at the air preheater outlet in the tower boiler unit.

[0012] Optionally, the outlet of the first pipe is connected to a slag bin.

[0013] Optionally, the outlet of the second pipe is connected to the industrial wastewater pipe in the plant area.

[0014] The above-described solution of this utility model has at least the following beneficial effects: The above-mentioned solution of this utility model collects fly ash at the outlet of the air preheater in the tower boiler unit through the air preheater ash hopper, cleans the ash in the air preheater ash hopper through a cleaning device that is switched and connected to the air preheater ash hopper, and discharges the wastewater for cleaning the air preheater through a drainage device that is switched and connected to the air preheater ash hopper. This achieves timely cleaning of ash accumulation in the air preheater outlet flue under low load conditions of the deep peak-shaving unit and reduces the ash accumulation load in the air preheater outlet flue. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the ash removal and drainage system of the tower boiler unit of this utility model; Figure 2 This is a schematic diagram showing the installation location of the air preheater ash hopper.

[0016] Explanation of reference numerals in the attached figures: 1: Air preheater ash hopper; 21: First pipeline; 22: Second pipeline; 3: Inspection door; 4: Expansion joint; 5: Pneumatic rotary feed valve; 6: Silo pump; 7: Mixer; 8: Hose; 9: Electric gate valve. Detailed Implementation

[0017] Exemplary embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0018] like Figure 1 and Figure 2 As shown, an embodiment of this utility model proposes a ash removal and drainage system for a tower boiler unit, comprising: A dust removal device that is switched and connected to the air preheater ash hopper 1 is used to clean the ash in the air preheater ash hopper 1; A drainage device that is switched and connected to the air preheater ash hopper 1 is used to discharge wastewater from cleaning the air preheater; The first pipe 21 connects the plurality of the dust removal devices; A second pipe 22 connecting multiple drainage devices; When multiple ash removal devices are conveying ash, the multiple ash removal devices discharge the accumulated ash in the air preheater ash hopper 1 through the first pipe 21; When the air preheater is being cleaned, multiple drainage devices discharge the wastewater from the air preheater through the second pipe 22.

[0019] In this embodiment, the air preheater ash hopper 1 is located at the horizontal bend of the air preheater outlet for collecting fly ash. Multiple cleaning devices are connected in series through a first pipe 21. The ash in the air preheater ash hopper 1 passes through the cleaning devices and is discharged through the first pipe 21. Multiple drainage devices are connected in series through a second pipe 22. The wastewater from cleaning the air preheater passes through the drainage devices and is discharged through the second pipe 22.

[0020] The above-mentioned ash removal device for tower boiler units of this utility model can, under low-load operation conditions, transport the accumulated ash at the bend of the horizontal flue at the air preheater outlet to the ash bin via a pneumatic ash conveying system, effectively reducing the ash load on the horizontal flue and lowering the risk of the air preheater outlet flue falling off. Simultaneously, due to the reduced ash load on the horizontal flue, the investment in the lower draft fan room and flue support of the horizontal flue can also be reduced. Under normal operating conditions, the lower ash hopper of the air preheater is connected to the first pipe 21; under shutdown conditions, when the air preheater needs flushing, it switches to the second pipe 22.

[0021] This embodiment employs two adjustable modes based on the operating conditions of the tower boiler unit: ash conveying mode under operating conditions and flushing mode under shutdown conditions.

[0022] Ash conveying mode under tower boiler unit operating conditions: A large amount of fly ash generated by boiler combustion settles at the bend in the flue after passing through the air preheater due to the reduced flow velocity in the horizontal flue outlet. This embodiment of the invention collects this accumulated ash using a cleaning device connected to the air preheater ash hopper 1. Multiple cleaning devices are connected in series to the first pipe 21 (ash conveying pipe). Specifically, ash in the air preheater ash hopper 1 falls into the cleaning device, which then operates, mixing the collected fly ash with compressed air in the mixer 7. The mixed ash is then conveyed to the slag bin via the first pipe 21 using pneumatic conveying, thus achieving ash removal.

[0023] Flushing mode during tower boiler unit shutdown: This mode is used for water flushing of the air preheater during unit shutdown and maintenance. After unit shutdown, the air preheater needs to be flushed. At this time, the ash removal device is disconnected from the air preheater ash hopper 1, and the air preheater ash hopper 1 is switched to the drainage device. The air preheater is then flushed with water through the drainage device, and the flushed wastewater and ash mixture flows out through the air preheater ash hopper 1. This wastewater is guided to the plant's industrial wastewater treatment system through the second pipeline 22 for centralized treatment.

[0024] This embodiment directly reduces the weight of ash accumulation in the horizontal flue, avoiding the risk of the flue cracking or falling off due to excessive load.

[0025] In some embodiments, the dust removal device includes: The ash conveying pipeline connected to the ash hopper 1 of the air preheater; The silo pump 6 is connected to the ash conveying pipeline; A mixer 7 is connected to the silo pump 6 and is connected to the first pipe 21; The ash in the ash hopper 1 of the air preheater is transported to the silo pump 6 through the ash conveying pipeline. The silo pump 6 then ejects the ash into the mixer 7, where the ash is mixed with compressed air. The compressed air then transports the ash to the slag silo through the first pipeline 21.

[0026] In this embodiment, the inlet of the dust removal device is directly connected to the outlet flange of the air preheater ash hopper 1 to guide the fly ash collected in the ash hopper. The silo pump 6 is connected to the outlet of the ash conveying pipeline, serving as the core sending unit of the system. The silo pump 6 is a pressure vessel that periodically receives fly ash and "ejects" it. The mixer 7 is installed after the outlet of the silo pump 6; its function is to thoroughly mix the fly ash from the silo pump 6 with high-pressure compressed air. The first pipeline 21 is connected to the outlet of the mixer 7, serving as the main pipeline for conveying the mixture to the terminal. Optionally, a compressed air source is provided on the mixer 7 to provide a compressed air system for power.

[0027] The ash conveying process in this embodiment can be intermittent or batch-based. A complete ash conveying process is as follows: 1. Feeding Stage. Fly ash is continuously collected in the air preheater ash hopper 1. When the ash level in the air preheater ash hopper 1 reaches the preset height (detected by the level gauge) or reaches the set time interval, an ash conveying cycle is started. The feed valve of the silo pump 6 is opened, and the fly ash falls into the silo pump 6 tank through the ash conveying pipeline under the action of gravity until it is full or reaches the set weight / level.

[0028] 2. Pressurization and Conveying Stage. The feed valve of silo pump 6 is closed and sealed. Subsequently, the valve of the compressed air source is opened, and high-pressure air enters the system in two paths: one path (main air) enters mixer 7, forming a high-speed airflow within mixer 7. The other path (auxiliary air or fluidizing air) may enter from the bottom of silo pump 6, helping to "fluidize" the fly ash within silo pump 6, making it easy to flow like a fluid. Under the combined action of the pressure within silo pump 6 and the negative pressure at mixer 7, the fluidized fly ash is pushed into mixer 7.

[0029] 3. Mixing and Launching Stage. In mixer 7, fly ash is vigorously and thoroughly mixed with high-speed compressed air to form an ash-air mixture. This high-energy mixture then enters the first pipe 21 and is transported at high speed to the distant slag bin.

[0030] 4. Purging and Standby Phase. After the fly ash in the silo pump 6 is emptied, the system will continue to blow compressed air for a period of time to ensure that all fly ash in the pipeline is emptied and to prevent pipeline blockage. Subsequently, all valves are closed, and the system waits for the start of the next ash conveying cycle.

[0031] This embodiment reliably removes accumulated ash from the air preheater area and transports it to a designated location through a cyclical process of "collection-loading-mixing-emission". This system is the direct actuator for solving the problem of ash accumulation in horizontal flues under low-load conditions, and its stable operation is crucial to ensuring the safety of the entire boiler flue system.

[0032] In some embodiments, an inspection door 3 and a pneumatic rotary feed valve 5 are sequentially arranged on the ash conveying pipeline along the direction of ash output; When the ash accumulation in the air preheater ash hopper 1 reaches a preset height, the inspection door 3 is in the open state, allowing the ash in the air preheater ash hopper 1 to fall into the ash conveying pipeline, and the pneumatic rotary feed valve 5 is opened, allowing the ash to fall into the silo pump 6.

[0033] In this embodiment, the inspection door 3 is a manual valve, normally in the open state, used for safety isolation. When subsequent pipelines, silo pump 6, or pneumatic rotary feed valve 5 require maintenance, this door can be closed to cut off the ash source and ensure maintenance safety. The pneumatic rotary feed valve 5 is driven by compressed air. Its function is to allow fly ash to pass through at the beginning of each ash conveying cycle and to cut off the ash flow and form a seal at the end of the feeding cycle, preparing for the pressurization and conveying of silo pump 6.

[0034] Normally, the inspection door 3 is in the open position. The pneumatic rotary feed valve 5 is in the closed position, used to isolate the air preheater ash hopper 1 from the silo pump 6. The silo pump 6 is under normal or low pressure. As fly ash accumulates in the air preheater ash hopper 1, when the ash level gauge detects that the accumulated ash has reached the preset height, the pneumatic rotary feed valve 5 is opened first. Under the action of gravity, the fly ash in the hopper falls smoothly into the silo pump 6 below through the opened inspection door 3 and the pneumatic rotary feed valve 5, until the silo pump 6 is full or reaches the set loading capacity.

[0035] In this embodiment, the inspection door 3 maintains the safety of the ash removal device. The pneumatic rotary feed valve 5 realizes the automation and sealing of the process. Its "open-close" action is the key to connecting the two stages of "feeding" and "conveying", ensuring that the silo pump 6 can be effectively pressurized, thereby completing the ash emission.

[0036] In some embodiments, the ash conveying pipeline is further provided with an expansion joint 4, which is disposed between the inspection door 3 and the pneumatic rotary feed valve 5.

[0037] Typically, the air preheater and its connected ash hopper and flue are large metal structures. During boiler start-up, shutdown, and load changes, the temperature fluctuates drastically, resulting in significant thermal expansion and contraction. This expansion and contraction can reach tens or even hundreds of millimeters. The expansion joint 4, however, is a flexible, expandable component. When the upstream air preheater ash hopper 1 and pipes move downwards or laterally due to heat, the expansion joint 4 can absorb or compensate for these displacements through its own compression, stretching, or deflection, ensuring the long-term safe and stable operation of the ash conveying system of the tower boiler unit.

[0038] In some embodiments, the drainage device includes: a hose 8 and an electrically operated gate valve 9 connected to the hose 8; When cleaning the air preheater, the ash conveying pipeline is disconnected, the hose 8 is connected to the air preheater ash hopper 1, the electric gate valve 9 is opened, and the wastewater from cleaning the air preheater is discharged to the industrial wastewater pipeline in the plant area.

[0039] In this embodiment, the hose 8 is typically a corrosion-resistant and pressure-resistant industrial hose (such as a rubber-lined hose 8, PVC hose 8, or metal hose 8), providing flexibility and quick connection. The electric gate valve 9 is a motor-driven gate valve that can be remotely or automatically controlled, serving as the main isolation and control valve in the flushing drainage system. It can reliably open or shut off large flows of wastewater.

[0040] In this embodiment, the working process of the flushing air preheater is as follows: 1. The unit is shut down, and the air preheater is flushed with water. The operator first removes the cleaning device used in normal operation from the outlet of the air preheater ash hopper 1.

[0041] 2. Then connect one end of the hose 8 to the outlet flange of the air preheater ash hopper 1. The flexibility of the hose 8 makes this connection operation simple and quick. Connect the other end of the hose 8 to the inlet of the electric gate valve 9, while the outlet of the electric gate valve 9 is pre-connected to the fixed pipeline leading to the industrial wastewater pipeline in the plant area.

[0042] 3. After preparation, open the electric gate valve 9. Begin high-pressure water flushing of the air preheater. The flushed wastewater containing ash and slag flows into the air preheater ash hopper 1 at the bottom of the air preheater. After collecting in the air preheater ash hopper 1, the wastewater flows by gravity sequentially through: the ash hopper, hose 8, the opened electric gate valve 9, and the plant's industrial wastewater pipeline. Finally, the wastewater is transported to the plant's industrial wastewater treatment system for centralized purification.

[0043] 4. After all flushing operations are completed, close the electric gate valve 9. Disconnect the hose 8 and reconnect the cleaning device back to the air preheater ash hopper 1 outlet to prepare for the next start-up of the unit.

[0044] In this embodiment, two distinct functions (dry ash conveying and wastewater discharge) are achieved under the same interface through simple pipeline switching, resulting in a high degree of system integration. The use of hose 8 and electric valve greatly simplifies the operation process of switching from operating mode to maintenance flushing mode, saving time and manpower. Electric gate valve 9 ensures controllable drainage flow and can be operated remotely, avoiding the risks associated with manual operation in a wastewater environment.

[0045] In some embodiments, the air preheater ash hopper 1 is equipped with a level gauge to detect whether the ash in the air preheater ash hopper 1 has reached a preset height.

[0046] As an example, the level gauge can be any of the following: radio frequency admittance level gauge, radar level gauge, or rotary paddle level gauge. Installing the level gauge ensures that the ash hopper will not become clogged, overloaded, or affect the normal operation of the boiler due to excessive ash accumulation, thereby ensuring the safety and stability of the entire system.

[0047] In some embodiments, the mixer 7 is connected in series with the first pipe 21.

[0048] In this embodiment, series connection is the most direct and simplest connection method, featuring a simple structure, fewer connection points and flanges, reduced potential leakage points, and lower complexity and cost in manufacturing, installation, and maintenance. Furthermore, the series design makes multiple mixers 7 an essential part of the conveying pipeline, effectively preventing problems such as ash deposition and blockage at the beginning of the pipeline. It establishes a good start for the entire conveying process, making subsequent conveying smoother.

[0049] In some embodiments, the air preheater ash hopper 1 is located at the bend of the horizontal flue at the air preheater outlet in a tower boiler unit.

[0050] refer to Figure 2 At the bend in a horizontal flue, the direction of flue gas flow changes. Due to centrifugal force and inertia, a large amount of fly ash carried in the flue gas will collide and settle at this point, making it the most prone to and most severely affected area for ash accumulation in the entire flue. Placing the air preheater ash hopper 1 directly at the bend in the horizontal flue actively and directly captures the fly ash that would otherwise accumulate there and promptly removes it through a cleaning device. This fundamentally minimizes static ash accumulation in the horizontal flue and directly solves the problem of flue cracking caused by excessive ash load.

[0051] In some embodiments, the outlet of the first pipe 21 is connected to a slag bin.

[0052] In this embodiment, the slag bin is a large container or storage silo used in thermal power plants to store large particles of slag discharged from the bottom of the boiler. Transporting the fly ash collected in the air preheater flue to the slag bin greatly saves investment and operating costs, while simplifying the system and ensuring the smooth implementation and long-term operation of the ash removal system.

[0053] In some embodiments, the outlet of the second pipe 22 is connected to an industrial wastewater pipe.

[0054] In this embodiment, the industrial wastewater pipeline is a dedicated pipeline system laid within the factory to collect and transport wastewater generated during industrial production. Discharging wastewater into the industrial wastewater pipeline ensures its safe, compliant, and orderly treatment. This solves a technical problem (flue gas ash accumulation) without causing new environmental problems.

[0055] In one application scenario, during normal operation of the unit, the air preheater ash hopper is connected to a cleaning device. Especially under low load conditions, ash accumulation is severe at the bend of the horizontal flue at the air preheater outlet. Connecting the ash hopper to the cleaning device allows the accumulated ash in the air preheater ash hopper 1 to be discharged through the cleaning device and the first pipe 21, which helps reduce the ash load in the horizontal flue between the air preheater outlet and the dust collector inlet. When the unit is shut down and the air preheater needs to be flushed, the drainage device is switched to the air preheater ash hopper 1, and the wastewater from cleaning the air preheater is discharged through the drainage device and the second pipe 22.

[0056] The working process of the ash removal device is as follows: During unit operation, the fly ash generated by boiler combustion is collected through the air preheater ash hopper 1. The ash removal device is connected to the air preheater ash hopper 1. When the ash accumulation height in the ash hopper reaches the set value, the ash removal device starts to work. The fly ash enters the silo pump 6 through the manual inspection door 3, expansion joint 4, and pneumatic rotary feed valve 5 on the ash removal device, and is mixed with compressed air in the mixer 7. It is then transported to the slag silo by compressed air. The manual inspection door 3 is a normally open valve, which is only closed when subsequent valves, expansion joint 4, etc. need maintenance. The pneumatic rotary feed valve 5 is opened when the ash removal device is working. The ash removal device discharges the accumulated ash through the first pipe 21. The pneumatic rotary feed valve 5 is closed when the ash removal device is stopped. When the air preheater needs to be flushed during unit shutdown and maintenance, the ash removal device is disconnected, the drainage device is connected to the air preheater ash hopper 1, the electric gate valve 9 is opened, and the wastewater from flushing the air preheater is sent to the plant's industrial wastewater pipeline through the drainage device and the second pipeline 22.

[0057] The solution described in the above embodiments of this utility model can effectively reduce ash accumulation at the bend of the horizontal flue at the air preheater outlet, reduce the ash load on the horizontal flue between the air preheater outlet and the dust collector inlet, and solve the problem of weld cracking and flue detachment at the air preheater outlet.

[0058] The above description is the preferred embodiment of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.

Claims

1. A tower boiler unit ash removal and drainage system, characterized in that, include: A cleaning device that is switched and connected to the air preheater ash hopper (1) is used to clean the ash in the air preheater ash hopper (1); A drainage device that is switched to the air preheater ash hopper (1) is used to discharge wastewater from cleaning the air preheater; The first pipe (21) connects the plurality of the cleaning devices. A second pipe (22) connecting multiple drainage devices; When multiple ash removal devices are conveying ash, the multiple ash removal devices discharge the accumulated ash in the air preheater ash hopper (1) through the first pipe (21); When the air preheater is cleaned, multiple drainage devices discharge the wastewater from the air preheater cleaning process through the second pipe (22).

2. The ash removal and drainage system for a tower boiler unit according to claim 1, characterized in that, The dust removal device includes: The ash conveying pipeline connected to the ash hopper (1) of the air preheater; The silo pump (6) is connected to the ash conveying pipeline. A mixer (7) is connected to the silo pump (6) and the mixer (7) is connected to the first pipe (21); The ash in the ash hopper (1) of the air preheater is transported to the silo pump (6) through the ash conveying pipeline. The silo pump (6) sends the ash into the mixer (7). The mixer (7) mixes the ash with compressed air and the compressed air transports the ash to the slag silo through the first pipeline (21).

3. The ash removal and drainage system for a tower boiler unit according to claim 2, characterized in that, The ash conveying pipeline is provided with an inspection door (3) and a pneumatic rotary feed valve (5) in sequence along the direction of ash output. When the ash accumulation in the air preheater ash hopper (1) reaches a preset height, the inspection door (3) is in the open state so that the ash in the air preheater ash hopper (1) falls into the ash conveying pipeline, and the pneumatic rotary feed valve (5) is opened so that the ash falls into the silo pump (6).

4. The ash removal and drainage system for a tower boiler unit according to claim 3, characterized in that, An expansion joint (4) is also provided on the ash conveying pipeline. The expansion joint (4) is located between the inspection door (3) and the pneumatic rotary feed valve (5).

5. The ash removal and drainage system for a tower boiler unit according to claim 2, characterized in that, The drainage device includes: a hose (8) and an electric gate valve (9) connected to the hose (8). When cleaning the air preheater, the ash conveying pipeline is disconnected, the hose (8) is connected to the air preheater ash hopper (1), the electric gate valve (9) is opened, and the wastewater from cleaning the air preheater is discharged to the industrial wastewater pipeline in the plant area.

6. The ash removal and drainage system for a tower boiler unit according to claim 2, characterized in that, The air preheater ash hopper (1) is equipped with a level gauge to detect whether the ash in the air preheater ash hopper (1) has reached a preset height.

7. The ash removal and drainage system for a tower boiler unit according to claim 2, characterized in that, The mixer (7) is connected in series with the first pipe (21).

8. The ash removal and drainage system for a tower boiler unit according to claim 1, characterized in that, The air preheater ash hopper (1) is located at the bend of the horizontal flue at the air preheater outlet in the tower boiler unit.

9. The ash removal and drainage system for a tower boiler unit according to claim 1, characterized in that, The outlet of the first pipe (21) is connected to the slag bin.

10. The ash removal and drainage system for a tower boiler unit according to claim 1, characterized in that, The outlet of the second pipe (22) is connected to the industrial wastewater pipe in the plant area.

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