Superheated steam radiant waste boiler and gasifier containing same

Abstract

This utility model relates to a superheated steam radiant waste boiler, belonging to the technical field of gasification waste heat recovery devices, and solves the problem that existing radiant waste boilers cannot efficiently produce stable superheated steam. Key technical points include: the main body of the radiant waste boiler includes a water-cooled wall connecting an upper collection box (steam-water outlet pipeline) and a lower collection box (boiler water inlet); an array of radially distributed water-cooled screens on the inner circumference of the water-cooled wall, including a saturated screen (whose upper / lower collection box connects to the upper / lower collection box to form a boiler water circulation path), a low-superheated screen (whose lower collection box connects to an external steam drum via a saturated steam inlet collection box, and whose upper collection box outputs low-superheated steam via a low-superheated steam outlet collection box), and a high-superheated screen (whose lower collection box receives low-superheated steam via a high-superheated steam inlet collection box, and whose upper collection box outputs superheated steam to the outside of the gasifier). This device is mainly used for waste heat recovery of high-temperature syngas and stable production of superheated steam in the gasifier system.

Description

Technical Field

[0001] This utility model relates to the technical field of gasification waste heat recovery devices. More specifically, this utility model relates to a superheated steam radiant waste boiler and a gasifier containing the same. Background Technology

[0002] In the field of carbonaceous material gasification, radiant waste boilers, as the core equipment for high-temperature sensible heat recovery from syngas, directly impact the energy efficiency and economy of the gasification system. Traditional fluidized bed gasifiers produce syngas at temperatures as high as 1300-1500°C, carrying a large amount of molten ash particles. To recover this sensible heat, industrially, a structure combining a radiant waste boiler with a screen-type heating surface is commonly used (e.g., invention patent CN118360083A discloses a novel fluidized bed gasifier radiant waste boiler and its heat recovery system). This structure typically recovers heat through membrane water-cooled walls and radiant heat exchange screens, producing byproduct steam to reduce system energy consumption.

[0003] The invention patent CN118360083A proposes an optimized scheme for radiative cooling space: a cylindrical radiative cooling space with a diameter no less than three times that of the throat pipe is set at the top of the waste heat boiler body, surrounded by a membrane water-cooled wall. High-temperature syngas enters through the throat pipe and first undergoes sufficient heat exchange within this space, allowing the molten slag particles to cool and solidify before entering the radiative heat exchange screen area arranged below. While this design alleviates the slagging problem caused by the direct flushing of the heat exchange screen by liquid molten slag, its heat exchange system still has significant limitations—it only produces saturated steam or superheated steam as a byproduct through a single-level radiative heat exchange screen, limiting the improvement in steam quality.

[0004] Furthermore, this type of single-stage heat exchange system reveals bottlenecks when dealing with high-parameter gasification processes: First, insufficient steam superheating capacity. While the radiant heat exchanger uses parallel steam pipes or water-cooled pipes (e.g., 5–8 pipes / group), which can produce superheated steam by connecting to a superheated steam drum, the short heat exchange path and single temperature gradient make precise control of steam superheating difficult. Second, low thermal energy utilization rate. During the cooling process of the syngas from 1350°C to 850°C, the heat in the high-temperature section (>1000°C) is not fully utilized for the generation of high-grade superheated steam, restricting the overall energy efficiency improvement of the system.

[0005] Furthermore, existing radiant waste boilers have high structural redundancy in their steam generation systems. For example, CN118360083A requires two-stage external saturated steam drum and superheated steam drum, connected to water-cooled walls and radiant heat exchangers via complex piping. This not only increases equipment investment but also results in high thermal inertia and delayed steam parameter response due to the long steam-water circulation path, making it prone to unstable steam flow and temperature when the gasification load fluctuates.

[0006] In summary, while current radiant waste boiler technology mitigates the risk of slagging by optimizing the slag cooling space, the single-stage nature of the steam generation system, insufficient cascade utilization of thermal energy, and equipment complexity still limit the efficient recovery of sensible heat from high-temperature syngas. Therefore, there is an urgent need to develop a radiant waste boiler system that integrates multi-stage superheating and has a compact structure, ensuring reliable anti-slagging capabilities while achieving flexible control of steam parameters and a significant increase in thermal energy quality. Utility Model Content

[0007] One object of this invention is to solve at least the problems described above and to provide at least the advantages that will be explained later.

[0008] Another objective of this invention is to provide a superheated steam radiant waste boiler that achieves deep utilization of the sensible heat of syngas through a tiered heat exchanger consisting of a saturated screen, a low-temperature screen, and a high-temperature screen, producing high-parameter superheated steam (up to 540°C). It also matches the syngas temperature gradient of 1350 to 850°C to achieve efficient heat recovery and improve thermal efficiency. At the same time, it replaces the external steam drum group with an internal header system, shortens the pipeline, eliminates the problem of steam parameter lag, and achieves a double leap in high-quality heat recovery and operational reliability.

[0009] To achieve these objectives and other advantages according to the present invention, a superheated steam radiant waste boiler is provided, comprising:

[0010] The main body of the radiant waste boiler includes a water-cooled wall, with an upper collection box connected to the upper part and a lower collection box connected to the lower part. The upper collection box is connected to the steam and water outlet pipeline, and the lower collection box is connected to the boiler water inlet.

[0011] The water-cooled screen group is arrayed on the inner circumference of the water-cooled wall and arranged radially along the inner circumference of the water-cooled wall. The water-cooled screen group includes a saturation screen, a low-pass screen and a high-pass screen. The upper header of the saturation screen is connected to the upper general header, and the lower header of the saturation screen is connected to the lower general header to form a boiler water circulation path.

[0012] The lower header of the low-superheated steam shield is connected to the steam inlet pipeline of the external steam drum through a saturated steam inlet collection header to receive the separated saturated steam; the upper header of the low-superheated steam shield is connected to the low-superheated steam pipeline through a low-superheated steam outlet collection header to output low-superheated steam; the lower header of the high-superheated steam shield is connected to the low-superheated steam pipeline through a high-superheated steam inlet collection header to receive low-superheated steam; and the upper header of the high-superheated steam shield is connected to the high-superheated steam pipeline to output superheated steam to the outside of the gasifier.

[0013] Preferably, the low-superheated steam pipeline is equipped with a water spray desuperheater to regulate the steam temperature of the output low-superheated steam.

[0014] Preferably, the top of the water-cooled wall is provided with an atomizing water device to form a low-temperature shielding water curtain channel at the inlet of the radiant waste cooker body, the atomizing water device comprising:

[0015] The annular water supply header is arranged circumferentially along the top of the water-cooled wall. Multiple atomizing nozzles are installed at the bottom of the annular water supply header. The installation angle of the atomizing nozzles is parallel to the central axis of the radiant waste boiler body. The atomized water sprayed by the atomizing nozzles is in the form of sheet-like water mist, and the overlap rate of adjacent sheet-like water mists is >20%.

[0016] Preferably, the water-cooled wall is provided with rapping devices at different heights on its outer side wall.

[0017] Preferably, the water-cooled wall is a cylindrical structure formed by multiple upright finned tubes, and the fins of adjacent finned tubes are laser-welded to form continuous spiral guide grooves. The spiral angle of the guide grooves is 30°~45°, and the spacing between adjacent guide grooves is 10~20mm.

[0018] Preferably, both the saturated steam inlet collection box and the supersteam inlet collection box have a conical diffuser section at their inlet ends, and the diffuser angle of the conical diffuser section is 15°~30°.

[0019] Preferably, a corrugated pipe compensator is provided at the connection between the upper header of the high-pressure screen and the high-pressure steam pipeline. The corrugated pipe compensator has 3 to 5 corrugations and an axial compensation amount of 20 to 50 mm.

[0020] Preferably, the lower collection box has a multi-stage flow guiding structure inside, which includes:

[0021] The primary partition wall consists of 8 to 12 main partitions evenly distributed around the lower collection box. The main partitions are 10 to 15 mm thick and 1 / 3 to 1 / 2 the height of the lower collection box's inner diameter. Fan-shaped diversion cavities are formed between adjacent main partitions.

[0022] The secondary partition wall consists of guide vanes set on both sides of each main partition, with an angle of 30° to 45° between them and the main partition. The surface of the guide vanes is provided with honeycomb-shaped turbulent microgrooves, with a groove depth of 0.5 to 1 mm and a groove width of 2 to 3 mm.

[0023] The three-level partition wall consists of an arc-shaped flow equalization perforation plate at the end of each main partition. The arc-shaped flow equalization perforation plate has flow equalization holes with a diameter of 5-8 mm and a spacing of 1.5-2 times the diameter of the holes. The radius of curvature of the arc-shaped flow equalization perforation plate matches the diameter of the inlet of the header under the saturation screen.

[0024] This utility model further claims a gasifier, which includes the superheated steam radiant waste boiler.

[0025] This utility model has at least the following beneficial effects:

[0026] Firstly, the superheated steam radiant waste boiler provided by this utility model has a stepped heat exchange structure of saturated screen → low superheat screen → high superheat screen, which fully matches the temperature gradient of syngas. Compared with the single-stage radiant heat exchange screen in the prior art, it can generate high-parameter superheated steam (>540℃), which greatly improves the heat recovery efficiency and avoids the risk of slagging on the heat exchange screen due to temperature gradient mismatch.

[0027] Secondly, the superheated steam radiation waste boiler top atomizing water device provided by this utility model forms a sheet-like water curtain with an overlap rate of >20%, constructing a low-temperature shielding layer, which enables high-temperature molten slag particles to solidify rapidly before contacting the water-cooled screen assembly; combined with the water-cooled wall outer vibrating device, it can effectively remove attached ash and slag, and eliminate the problem of slag blockage caused by liquid slag flushing of the heat exchange screen.

[0028] Thirdly, the spiral guide groove (30°–45° rise angle) laser-welded between the finned tubes of the superheated steam radiant waste boiler water-cooled wall provided by this utility model enhances the turbulent heat transfer of syngas and improves the wall heat transfer coefficient; the three-stage guide structure of the lower collection box accurately distributes the flow through honeycomb microgrooves and flow equalization orifice plates, reducing the flow deviation of each water-cooled screen. Compared with the existing technology, it sets up an external steam drum group, shortens the pipeline, eliminates steam parameter lag, and ensures the stability of superheated steam temperature when the gasification load fluctuates.

[0029] Other advantages, objectives and features of this invention will be partly apparent from the following description, and partly understood by those skilled in the art through study and practice of this invention. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the first cross section of the superheated steam radiant waste boiler described in one of the technical solutions of this utility model;

[0031] Figure 2 This is a schematic diagram of the second cross section of the superheated steam radiant waste boiler described in another technical solution of this utility model;

[0032] Figure 3 This is a schematic diagram of the third cross section of the superheated steam radiant waste boiler described in another technical solution of this utility model;

[0033] Figure 4 This is a schematic diagram of the gasifier described in another technical solution of this utility model;

[0034] Among them, 100 is the combustion chamber; 200 is the superheated steam radiant waste boiler; 300 is the quench chamber; 1 is the upper collection box; 2 is the lower collection box; 31 is the steam-water outlet; 32 is the boiler water inlet; 4 is the low-pressure screen; 41 is the lower collection box of the low-pressure screen; 42 is the upper collection box of the low-pressure screen; 5 is the water-cooled wall; 6 is the saturated screen; 61 is the upper collection box of the saturated screen; 62 is the lower collection box of the saturated screen; 7 is the saturated steam inlet; 71 is the saturated steam inlet collection box; 8 is the superheated steam outlet; 9 is the high-pressure screen; 91 is the upper collection box of the high-pressure screen; 92 is the lower collection box of the high-pressure screen; 10 is the high-pressure steam inlet collection box; 11 is the low-pressure steam outlet collection box; 12 is the water spray desuperheater; 13 is the water spray desuperheater port; 14 is the rapping device; 15 is the atomizing water device; and 16 is the syngas outlet. Detailed Implementation

[0035] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0036] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0037] like Figures 1-3 As shown, this utility model provides a superheated steam radiant waste boiler 200, including: a radiant waste boiler body, which includes a water-cooled wall 5, the upper part of the water-cooled wall 5 is connected to an upper collection box 1 and the lower part is connected to a lower collection box 2, the upper collection box 1 is connected to a steam-water outlet 31 pipeline, and the lower collection box 2 is connected to a boiler water inlet 32.

[0038] The water-cooled screen group is arrayed on the inner circumference of the water-cooled wall 5 and arranged radially along the inner circumference of the water-cooled wall 5. The water-cooled screen group includes a saturation screen 6, a low-pass screen and a high-pass screen; the upper header 61 of the saturation screen is connected to the upper general header 1, and the lower header 62 of the saturation screen is connected to the lower general header 2 to form a boiler water circulation passage.

[0039] The lower header 41 of the low-superheated steam shield is connected to the steam inlet pipeline of the external steam drum through the saturated steam inlet collection header 71 to receive the separated saturated steam; the upper header 42 of the low-superheated steam shield is connected to the low-superheated steam pipeline through the low-superheated steam outlet collection header 11 to output low-superheated steam; the lower header 92 of the high-superheated steam shield is connected to the low-superheated steam pipeline through the high-superheated steam inlet collection header 10 to receive low-superheated steam; and the upper header 91 of the high-superheated steam shield is connected to the high-superheated steam pipeline to output superheated steam to the outside of the gasifier.

[0040] Superheated steam radiant waste boilers are generally used in gasification furnace systems. Existing gasification furnace systems include a combustion chamber 100, a superheated steam radiant waste boiler 200, and a quench chamber 300 arranged sequentially from top to bottom.

[0041] In the above technical solution, the main body of the radiant waste boiler is formed by water-cooled walls 5, creating a chamber that withstands high-temperature radiant heat. The upper and lower parts of the water-cooled walls 5 are respectively connected to the upper collection tank 1 and the lower collection tank 2, forming the main circulation loop of the boiler water. The shells of the upper collection tank 1 and the lower collection tank 2 are typically made of large-diameter carbon steel or alloy steel pipes, such as DN250-DN400. Boiler water enters from the lower collection tank 2 (located at the bottom of the radiant waste boiler body), absorbs the radiant heat of the high-temperature syngas, and partially vaporizes. The steam-water mixture rises to the upper collection tank 1 (located at the top of the radiant waste boiler body) and is discharged through the steam-water outlet 31 pipeline. On the inner circumference enclosed by the water-cooled walls 5, multiple sets of water-cooled screens are arranged radially in an array. The water-cooled screen sets include saturation screens 6, low-overflow screens 4, and high-overflow screens 9. Among them, the saturation screen 6 is directly connected to the main circulation loop of the boiler water, the upper header 61 of the saturation screen is connected to the upper collection header 1, and the lower header 62 of the saturation screen is connected to the lower collection header 2, as part of the main circulation loop to participate in the generation of saturated steam.

[0042] In the above technical solution, the superheating function is achieved by a series of low-overheating and high-overheating screens. The separated saturated steam (from the external steam drum) enters the saturated steam inlet collection box 71 (installed in the annular cavity space between the superheated steam radiant waste boiler and the gasifier shell) through the saturated steam inlet 7, and is then distributed to the lower collection box 41 of the low-overheating screen. After absorbing heat and rising in temperature in the low-overheating screen, it flows out from the upper collection box 42 of the low-overheating screen and is collected in the low-overheating steam outlet collection box 11 (installed in the upper part of the annular cavity space between the superheated steam radiant waste boiler and the gasifier shell) to the low-overheating steam pipeline. This low-temperature superheated steam then enters the high-temperature superheated steam inlet header 10 (installed in the lower part of the annular cavity space between the superheated steam radiant waste boiler and the gasifier shell), and is distributed to the lower header 92 of the high-temperature superheated screen. Within the high-temperature superheated screen, it further absorbs high-temperature radiant heat to reach the final required superheated temperature (up to 540°C). Finally, the superheated steam is directly output from the upper header 91 of the high-temperature superheated screen to the high-temperature superheated steam pipeline (usually connected to the superheated steam outlet 8 at the top of the superheated steam radiant waste boiler). All headers are connected to the water-cooled wall 5 and the water-cooled screen by welding.

[0043] According to the above technical solution, a specific working process of the superheated steam radiant waste boiler 200 provided by this utility model is as follows:

[0044] High-temperature syngas enters the central chamber of the radiant waste boiler from the gasifier, where its intense radiant heat is absorbed by the inner surface of the water-cooled wall 5. Boiler water enters the tube bundle of the water-cooled wall 5 from the lower collection box 2, absorbing heat as it flows upward. Some of the water vaporizes into steam, forming a steam-water mixture that rises to the upper collection box 1 at the top, and is then sent to the external steam drum for steam-water separation via the steam-water outlet 3 pipeline. Simultaneously, the saturated screen 6, arranged on the inner circumference of the water-cooled wall 5 as an extension of the main water-cooled wall 5, also undergoes heating and partial vaporization of its internal working fluid (boiler water), and the steam-water mixture also flows into the upper collection box 1.

[0045] Saturated steam (approximately 300°C) separated within the external steam drum is drawn out and evenly distributed to the lower headers 41 of each low-superheated screen via the saturated steam inlet header 71. The saturated steam flows upward within the low-superheated screen tubes, absorbing radiant heat from the high-temperature syngas, resulting in a significant temperature increase (approximately 430°C), becoming low-superheated steam. This steam is then collected at the low-superheated steam outlet header 11 and output through the low-superheated steam pipeline. This low-superheated steam is then introduced into the high-superheated steam inlet header 10 and distributed to the lower headers 92 of each high-superheated screen. The low-superheated steam continues to flow upward within the high-superheated screen tubes, and under radiant heating, its superheated temperature further increases (up to 540°C), ultimately becoming high-parameter superheated steam, which is directly transported from the upper header 91 of the high-superheated screen to the high-superheated steam pipeline outside the gasifier for downstream use.

[0046] The core advantage of the above technical solution lies in directly integrating the superheating process of saturated steam into the high-temperature radiant waste boiler, fully utilizing the radiant heat energy of the high-temperature syngas and significantly improving energy utilization efficiency. In traditional designs, superheaters are often located in the convection section or set up separately, with the heat source being the convection heat transfer of the relatively low-temperature flue gas, resulting in relatively low efficiency. In contrast, this solution utilizes the strong heat flow in the core high-temperature zone of the radiant section for superheating, resulting in higher heat intensity and stronger heat transfer capacity per unit area. This allows for more efficient heating of saturated steam to the required high-temperature superheated state, effectively reducing the unit energy consumption of the final superheated steam.

[0047] The superheated steam structure provided by this utility model has a compact design and high space utilization. The water-cooled screen group (saturated screen 6, low-level superheated screen, and high-level superheated screen) is arranged radially along the inner circumference of the water-cooled wall 5, without occupying the central channel space of the radiant waste boiler, ensuring smooth airflow. At the same time, it integrates boiler water circulation, saturated steam generation, and two-stage superheating (low-level and high-level superheating) functions in one device, simplifying the gasifier structure, reducing the need for external connection pipes and support structures, lowering equipment manufacturing costs and installation complexity, and making the layout of the entire steam generation and superheating system more reasonable and compact.

[0048] Furthermore, the separated circulation paths enhance operational safety and flexibility. Boiler water in the main circulation loop (water-cooled wall 5 + saturated screen 6) and saturated steam in the superheating loop (low-level superheater + high-level superheater) are physically isolated. Saturated screen 6 directly participates in water circulation, ensuring its tube walls are adequately cooled, avoiding the risk of overheating due to insufficient steam flow that may occur with traditional superheaters at low loads or during startup. The low-level and high-level superheaters are specifically designed for steam superheating; their flow rate and temperature can be independently adjusted through the separation effect of the external steam drum and the steam extraction rate, making it easier to precisely control the parameters (temperature, pressure) of the final superheated steam and improving the system's operational flexibility and reliability.

[0049] In one of the technical solutions, a water spray desuperheater 12 is provided on the low-superheated steam pipeline to regulate the steam temperature of the output low-superheated steam.

[0050] The above technical solution achieves precise temperature control by adding a water spray desuperheater 12 to the low-superheat steam pipeline between the low-superheat steam outlet collection box 11 and the high-superheat steam inlet collection box 10. The water spray desuperheater 12 is a standard component from a power plant boiler, such as the PW series from Harbin Boiler / Dongfang Boiler, with a working pressure ≤16MPa and a temperature resistance ≤450℃. The desuperheating water is drawn from the boiler feedwater pump outlet branch pipe and injected vertically into the center of the steam flow via a multi-hole atomizing spray gun through the water spray desuperheating port 13. The atomized particle size ≤50μm ensures rapid vaporization. The water spray desuperheater 12 positions the temperature control point between the low-superheat and high-superheat sections, allowing the high-superheat screen to focus on steadily improving the superheat grade without frequent adjustments to its heating surface. Compared to the traditional method of adjusting the temperature at the high-superheat outlet, this improves the accuracy of steam temperature control and avoids thermal stress fatigue caused by drastic temperature changes in the working fluid within the high-superheat screen. Furthermore, when the gasifier load changes abruptly, the steam temperature response at the outlet of the low-pressure bypass screen lags by approximately 30-60 seconds. The water spray desuperheater 12 rapidly smooths out temperature fluctuations through millisecond-level atomization heat exchange, preventing the high-pressure bypass screen from experiencing a decrease in pipe strength due to inlet overheating, thus preventing pipe rupture accidents. Simultaneously, the desuperheating water directly absorbs the heat from the steam and converts it into effective steam, resulting in zero working fluid waste. It also extends the service life of the high-pressure bypass screen by preventing overheating, reducing unplanned downtime losses.

[0051] In one technical solution, the top of the water-cooled wall 5 is provided with an atomizing water device 15 to form a low-temperature shielding water curtain channel at the inlet of the radiant waste cooker body. The atomizing water device 15 includes:

[0052] The annular water supply header is arranged circumferentially along the top of the water-cooled wall 5. Multiple atomizing nozzles are installed at the bottom of the annular water supply header. The installation angle of the atomizing nozzles is parallel to the central axis of the radiant waste boiler body. The atomized water sprayed by the atomizing nozzles is in the form of sheet-like water mist, and the overlap rate of adjacent sheet-like water mists is >20%.

[0053] In the above technical solution, the atomizing water device 15 achieves inlet protection for high-temperature syngas through an annular structure integrated on the top of the radiant waste boiler body. The annular water supply header is horizontally welded and fixed along the inner circumference of the top of the water-cooled wall 5, and multiple sets of atomizing nozzles are evenly installed directly below it. The annular water supply header can be made of 06Cr19Ni10 stainless steel or nickel-based alloy, with a diameter of DN100-DN150. The atomizing nozzles can be Lechler's SKP series fan-shaped nozzles, made of 310S heat-resistant steel or nickel-based alloy, with a temperature resistance ≥1200℃. The atomizing nozzle installation angle is strictly parallel to the central axis of the radiant waste boiler, ensuring that the spray direction is in the same direction as the high-temperature airflow. The spacing between the atomizing nozzles is optimized through fluid simulation, so that the sprayed sheet-like water mist forms a continuous annular water curtain in the axial direction, with an overlap rate of >20% between adjacent water mists (the measured value is usually 25%~40%), completely covering the inlet section.

[0054] In the above technical solution, when the high-temperature syngas enters the radiant waste boiler body from the gasifier, it first impacts the activated atomizing water device 15 at the top. Boiler feedwater is pumped from external pipelines into the annular water supply header, and then distributed to each atomizing nozzle. The atomizing nozzles pulverize the water flow into micron-sized droplets, which are then sprayed vertically downwards in the form of sheet-like water mist (flow velocity 15~30m / s), forming a low-temperature shielded water curtain channel with a height of 300~500mm at the inlet. When the high-temperature syngas passes through the water curtain, the water mist instantly absorbs heat and vaporizes. The molten ash particles it carries undergo forced heat exchange with the water mist, and the surface of the molten ash solidifies due to rapid cooling, losing its adhesiveness and preventing coking on the surface of the water-cooled wall 5.

[0055] In the above technical solution, the atomizing water device 15 significantly reduces the direct thermal shock of high-temperature syngas to the equipment through a dual mechanism of physical barrier and phase change heat absorption. The transient cooling effect of the water curtain reduces the inlet temperature by 300~400℃, which not only protects the welds and headers of the water-cooled wall 5 (avoiding high-temperature creep failure), but more importantly, it blocks slag adhesion. After the ash solidifies, its hardness increases, and it falls directly into the water area of ​​the gasifier quench chamber, reducing the risk of coking in the radiation section by more than 90% and extending the continuous operation cycle.

[0056] In one technical solution, rapping devices are installed at different heights on the outer wall of the water-cooled wall 5. These devices can be DEBO DZ series rappers from Germany. Based on the deposition pattern of ash and slag being higher at the bottom than at the top, the rapping devices installed at lower heights employ a bottom-up, layered rapping strategy to avoid secondary adhesion of ash and slag. The detached ash and slag enter the downstream ash hopper with the synergistic gas flow. Mechanical rapping directly breaks the bonding force between the ash and slag and the pipe wall through directional shock waves, improving the thoroughness of ash removal and ensuring that the water-cooled wall 5 maintains its designed heat transfer coefficient and stable steam production over the long term. Simultaneously, the rapping devices and the atomizing water device 15 work synergistically. The rapping devices remove dry ash deposits, while the atomizing water device 15 inhibits molten slag adhesion, with the dual mechanisms covering all types of ash and slag.

[0057] In one of the technical solutions, the water-cooled wall 5 is a cylindrical structure formed by multiple upright finned tubes. The fins of adjacent finned tubes are laser-welded to form a continuous spiral guide groove. The spiral angle of the guide groove is 30°~45°, and the distance between adjacent guide grooves is 10~20mm.

[0058] The above technical solution achieves directional flow of ash and slag by optimizing the structure of the water-cooled wall 5 tubes. The water-cooled wall 5 consists of multiple upright finned tubes forming a cylindrical main body. The fins of adjacent finned tubes are laser-welded using an industrial fiber laser (such as an IPG YLS-6000, 6kW power) to form continuous spiral flow channels. The spiral trajectory welding is completed simultaneously during tube-panel assembly, ensuring the flow channels are continuous from the top to the bottom of the water-cooled wall 5. The preferred height of the fins is 15-20mm, the thickness is 6mm, and the weld penetration depth is at least 4mm. The spiral angle of the flow channels is strictly controlled between 30° and 45°, preferably 38°±2°. The depth of the flow channels is equal to the fin height, and the center-to-center distance between adjacent flow channels is 10-20mm, preferably 15mm.

[0059] According to the above technical solution, when the high-temperature syngas carries the molten ash downwards through the water-cooled wall 5: the low-temperature water curtain formed at the top by the atomizing water device 15 causes the ash to initially solidify into semi-molten particles (temperature 600~800℃); when the semi-molten particles contact the inner surface of the water-cooled wall 5, they are captured by the spiral guide groove. The groove wall applies a tangential force to the semi-molten particles, driving them to rotate downwards at a spiral angle of 30°~45° and accelerate, avoiding local accumulation caused by vertical fall; the semi-molten particles are continuously cooled by the water-cooled wall 5 during the rotation and descent, and are completely solidified at the bottom (temperature <300℃), forming loose fragments; when the rapping device is activated in layers, the shock wave is transmitted along the pipe wall, causing the solidified slag layer in the groove to be broken and detached by torsional shear force. The detached slag particles are accelerated and discharged into the bottom ash hopper along the spiral groove trajectory, reducing the ash removal resistance and thus improving the ash removal efficiency.

[0060] The above-mentioned technical solution innovatively solves the problems of ash accumulation and corrosion. Traditional vertical finned tubes are prone to slag accumulation at the bottom of the tank (forming a corrosion source), while the spiral guide channel, through forced rotation and transportation, shortens the residence time of ash particles and reduces the penetration of corrosive gases. On the other hand, it increases the turbulence of the airflow, destroys the ash deposition boundary layer, and reduces the annual corrosion rate. At the same time, the spiral guide channel creates a swirling effect in the syngas, increases the gas-solid contact frequency, improves the convective heat transfer coefficient of the water-cooled wall, and forms a mechanical resonance with the rapping device, increasing the propagation distance of the rapping shock wave along the spiral guide channel and increasing the ash cleaning area coverage.

[0061] In one of the technical solutions, both the saturated steam inlet collection box 71 and the supersteam inlet collection box 10 are provided with conical diffuser sections at their inlet ends, and the diffuser angle of the conical diffuser section is 15°~30°.

[0062] The above technical solution achieves uniform steam distribution by optimizing the inlet flow channel structure of the steam collection header. At the inlet ends of the saturated steam inlet collection header 71 (connected to the lower header below the lower overpass) and the higher steam inlet collection header 10 (connected to the lower header below the higher overpass), i.e., inside the flange connection with the external pipeline, a conical diffuser section is integrated. The material of the diffuser section is the same as that of the header. The diffuser section is CNC spun forming, and its diffuser angle is strictly controlled between 15° and 30°, preferably 22°±2°. The inlet diameter matches the steam pipeline, and the outlet diameter is expanded to the inner diameter of the header.

[0063] According to the above technical solution, the saturated steam distribution process is as follows: When the saturated steam output from the external steam drum enters the saturated steam inlet header 71 through the steam inlet pipeline, it first passes through the 15°~30° conical diffuser section; the kinetic energy of the steam flow is converted into pressure energy in the expanding cone, the flow velocity decreases, and the inlet vortex is eliminated; the low-speed steam evenly fills the entire header section and is stably distributed to each lower header of the low-speed screen, with small flow deviation. The secondary distribution process of low-temperature superheated steam is as follows: After passing through the water spray desuperheater 12 (the low-temperature superheated steam, after temperature adjustment, enters the high-temperature superheated steam inlet header 10, it also passes through the conical diffuser section; the diffuser section suppresses the steam flow pulsation caused by the desuperheating water spray, preventing steam carrying water droplets from impacting the inlet pipe wall of the high-temperature superheated screen; the steam after equalization smoothly enters the lower header 92 of the high-temperature superheated screen, avoiding local overheating of the tube screen due to uneven distribution. Traditional straight-through headers generate a backflow dead zone due to sudden expansion, resulting in a flow deviation of more than 30% in the branch pipes. The conical diffuser section, through gradual diffusion, makes the steam flow line transition smoothly and ensures the uniformity of steam flow in each water-cooled screen, eliminating the risk of local overheating and tube rupture.

[0064] In one of the technical solutions, a corrugated pipe compensator is provided at the connection between the upper header 91 of the high-speed screen and the high-speed steam pipeline. The corrugated pipe compensator has 3 to 5 corrugations and an axial compensation amount of 20 to 50 mm.

[0065] The above technical solution addresses the thermal displacement problem by integrating a bellows compensator between the header on the high-pressure superheated steam pipe and the connecting flange of the high-pressure superheated steam pipeline. The compensator uses a general-purpose axial double bellows, designed with 3-5 bellows, preferably 4. The axial compensation amount strictly matches the design value of 20-50mm, and during cold-tightening installation, it is pre-compressed by 50% of the compensation amount (10-25mm).

[0066] According to the above technical solution, during the cold start-up phase, the bellows compensator is in a compressed state. As the boiler heats up, the pressure plate undergoes axial thermal expansion, and the bellows gradually releases its pre-compression to absorb the elongation displacement of the pressure plate, preventing the weld seam of the header on the pressure plate from bearing tensile stress. During the fluctuating operation phase, when the gasifier load changes abruptly, the steam temperature at the pressure plate outlet changes instantaneously, causing the pressure plate to expand and contract rapidly. The bellows, with its flexible structure, responds quickly by deforming, with the compensation amount dynamically changing by ±5mm. During the bellows deformation process, the absolute displacement of the sealing surface is maintained, preventing flange leakage. During the shutdown and cooling phase, the bellows rebounds to its pre-compressed state, preparing for the next startup. The bellows compensator not only eliminates the risk of thermal stress damage but also ensures sealing safety and system stability, essentially achieving maintenance-free operation.

[0067] In one technical solution, the lower collection box 2 is provided with a multi-stage flow guiding structure, which includes:

[0068] The primary partition wall consists of 8 to 12 main partitions evenly distributed around the lower collection box 2. The main partitions are 10 to 15 mm thick and 1 / 3 to 1 / 2 of the inner diameter of the lower collection box 2. A fan-shaped diversion cavity is formed between adjacent main partitions.

[0069] The secondary partition wall consists of guide vanes set on both sides of each main partition, with an angle of 30° to 45° between them and the main partition. The surface of the guide vanes is provided with honeycomb-shaped turbulent microgrooves, with a groove depth of 0.5 to 1 mm and a groove width of 2 to 3 mm.

[0070] The three-level partition wall consists of an arc-shaped flow equalization perforation plate at the end of each main partition. The arc-shaped flow equalization perforation plate has flow equalization holes with a diameter of 5-8 mm and a spacing of 1.5-2 times the diameter of the holes. The radius of curvature of the arc-shaped flow equalization perforation plate matches the diameter of the inlet of the lower header of the saturation screen 6.

[0071] The above technical solution optimizes boiler water distribution by integrating a three-stage flow guiding structure inside the lower header 2, forming a path of primary flow diversion, secondary flow guidance, and tertiary flow equalization. Eight to twelve main baffles are welded to the inner wall of the lower header 2, with the height of the main baffles being 40% of the inner diameter of the header, dividing the inner cavity of the lower header 2 into fan-shaped flow diversion chambers. Flow guide vanes are welded to both sides of each main baffle, with an inclination angle of 30° to 45°. Honeycomb-shaped turbulent microgrooves are laser-etched on the surface of the flow guide vanes. An arc-shaped flow equalization orifice plate is bolted to the end of the main baffle, with a radius of curvature R equal to the inlet diameter of the lower header of the saturation screen 6. The orifice plate has an opening diameter of 6mm, an orifice spacing of 10mm (porosity 40%), and a rounded corner R0.5mm at the orifice edges.

[0072] According to the above technical solution, during the first-stage diversion, boiler feedwater rushes into the lower header 2 and impacts the circumferentially distributed main baffles; the water flow is divided into multiple equal-flow branches, flowing axially along the fan-shaped chamber, eliminating circumferential flow deviation. During the second-stage diversion, the water flow contacts the inclined guide vanes on both sides of the main baffle, turning along the vane surface to form a vortex; the honeycomb microgrooves on the vane surface stimulate micro-scale turbulence, destroying the boundary layer and preventing scale deposition. During the third-stage flow equalization, when the water flow passes through the arc-shaped flow equalization orifice plate, the curvature of the orifice plate matches the inlet streamline of the saturation screen 6; the 6mm diameter flow equalization orifice produces a throttling effect, balancing the kinetic energy at the inlet of each branch pipe; the water flow smoothly enters the lower header 62 of the saturation screen, seamlessly connecting with the upward flow of the spiral guide water-cooled wall 5. The three-stage diversion structure fundamentally solves the problem of unstable boiler hydrodynamics, while the continuous micro-turbulence of the honeycomb turbulent microgrooves prevents scale crystal growth, reducing annual scaling efficiency, and the guide vanes improve the corrosive gas carry-out rate and mitigate the risk of pitting corrosion.

[0073] like Figure 4 This utility model further claims a gasifier, which includes the superheated steam radiant waste boiler 200. The gasifier achieves efficient waste heat recovery by directly integrating the superheated steam radiant waste boiler 200 downstream of the syngas outlet 16. High-temperature syngas enters vertically downwards into the central chamber of the superheated steam radiant waste boiler 200. A specific implementation structure of the gasifier includes, from top to bottom, a combustion chamber 100, the superheated steam radiant waste boiler 200, and a quench chamber 300.

[0074] The number of devices and processing scale described herein are for the purpose of simplifying the description of this utility model. Applications, modifications, and variations of this utility model's superheated steam radiant waste boiler and gasifier containing it will be readily apparent to those skilled in the art.

[0075] Although the embodiments of this utility model have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for this utility model. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, this utility model is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A superheated steam radiant waste boiler, characterized in that, include: The main body of the radiant waste boiler includes a water-cooled wall, with an upper collection box connected to the upper part and a lower collection box connected to the lower part. The upper collection box is connected to the steam and water outlet pipeline, and the lower collection box is connected to the boiler water inlet. A water-cooled screen assembly is arranged in an array on the inner circumference of the water-cooled wall and radially along the inner circumference of the water-cooled wall. The water-cooled screen assembly includes a saturation screen, a low-pass screen, and a high-pass screen. The upper header of the saturation screen is connected to the upper and lower headers, and the lower header of the saturation screen is connected to the lower header to form a boiler water circulation path. The lower header of the low-superheated steam shield is connected to the steam inlet pipeline of the external steam drum through a saturated steam inlet collection header to receive the separated saturated steam; the upper header of the low-superheated steam shield is connected to the low-superheated steam pipeline through a low-superheated steam outlet collection header to output low-superheated steam; the lower header of the high-superheated steam shield is connected to the low-superheated steam pipeline through a high-superheated steam inlet collection header to receive low-superheated steam; and the upper header of the high-superheated steam shield is connected to the high-superheated steam pipeline to output superheated steam to the outside of the gasifier.

2. The superheated steam radiant waste boiler as described in claim 1, characterized in that, The low-superheated steam pipeline is equipped with a water spray desuperheater to regulate the steam temperature of the output low-superheated steam.

3. The superheated steam radiant waste boiler as described in claim 1, characterized in that, The top of the water-cooled wall is equipped with a water atomizing device to form a low-temperature shielding water curtain channel at the inlet of the radiant waste cooker body. The water atomizing device includes: The annular water supply header is arranged circumferentially along the top of the water-cooled wall. Multiple atomizing nozzles are installed at the bottom of the annular water supply header. The installation angle of the atomizing nozzles is parallel to the central axis of the radiant waste boiler body. The atomized water sprayed by the atomizing nozzles is in the form of sheet-like water mist, and the overlap rate of adjacent sheet-like water mists is >20%.

4. The superheated steam radiant waste boiler as described in claim 1, characterized in that, The water-cooled wall is equipped with rapping devices at different heights on its outer side wall.

5. The superheated steam radiant waste boiler as described in claim 4, characterized in that, The water-cooled wall is a cylindrical structure formed by multiple upright finned tubes. The fins of adjacent finned tubes are laser-welded to form continuous spiral guide grooves. The spiral angle of the guide grooves is 30°~45°, and the distance between adjacent guide grooves is 10~20mm.

6. The superheated steam radiant waste boiler as described in claim 1, characterized in that, Both the saturated steam inlet collection box and the supersteam inlet collection box are provided with a conical diffuser section at their inlet ends, and the diffuser angle of the conical diffuser section is 15°~30°.

7. The superheated steam radiant waste boiler as described in claim 1, characterized in that, A corrugated pipe compensator is provided at the connection between the upper header of the high-pressure shield and the high-pressure steam pipeline. The corrugated pipe compensator has 3 to 5 corrugations and an axial compensation of 20 to 50 mm.

8. The superheated steam radiant waste boiler as described in claim 1, characterized in that, The lower collection box is equipped with a multi-stage flow guiding structure, which includes: The primary partition wall consists of 8 to 12 main partitions evenly distributed around the lower collection box. The main partitions are 10 to 15 mm thick and 1 / 3 to 1 / 2 the height of the lower collection box's inner diameter. Fan-shaped diversion cavities are formed between adjacent main partitions. The secondary partition wall consists of guide vanes set on both sides of each main partition, with an angle of 30° to 45° between them and the main partition. The surface of the guide vanes is provided with honeycomb-shaped turbulent microgrooves, with a groove depth of 0.5 to 1 mm and a groove width of 2 to 3 mm. The three-level partition wall consists of an arc-shaped flow equalization perforation plate at the end of each main partition. The arc-shaped flow equalization perforation plate has flow equalization holes with a diameter of 5-8 mm and a spacing of 1.5-2 times the diameter of the holes. The radius of curvature of the arc-shaped flow equalization perforation plate matches the diameter of the inlet of the header under the saturation screen.

9. A gasifier, characterized in that, The gasifier includes the superheated steam radiant waste boiler as described in any one of claims 1 to 8.

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