Waste heat boiler equipment and boiler system

Abstract

The utility model relates to waste heat boiler equipment and a boiler system, the waste heat boiler equipment comprises a channel, a superheater and a first soot blower, and the channel is suitable for introducing flue gas for recovering heat and guiding the flue gas to flow; the superheater is arranged in the channel and is suitable for recycling heat of flue gas in the channel; the first soot blower is arranged in the channel, the first soot blower is located on the upstream of the superheater in the conveying direction of the channel, the first soot blower is suitable for blowing soot on the wall face in the channel, the channel comprises a first channel section, a second channel section and a third channel section, and the first soot blower is arranged on the first channel section and / or the second channel section; the superheater is arranged in the third channel section; ash hoppers are arranged at the bottoms of the first channel section, the second channel section and the third channel section; water wall tubes are arranged in the first channel section and the second channel section. The waste heat boiler equipment can solve the problems that in the prior art, the heat exchange efficiency is low, the outlet temperature is high, and high-temperature corrosion and pipe explosion are prone to happening to local parts of a boiler.

Description

Technical Field

[0001] The embodiments of this utility model relate to the field of waste heat recovery technology, and in particular to a waste heat boiler device and a boiler system. Background Technology

[0002] To fully utilize heat, existing technologies, such as feeding the high-temperature, dust-laden gas produced by biomass gasification furnaces into waste heat boilers for heat recovery, present challenges. However, during the heat recovery process from syngas, waste heat boilers suffer from reduced heat exchange efficiency, excessive outlet temperature, susceptibility to localized high-temperature corrosion and tube rupture, and low ash removal efficiency. Utility Model Content

[0003] The present invention aims to at least partially solve one of the technical problems in the background or related technologies described above.

[0004] Therefore, this utility model provides a waste heat boiler device that can solve problems such as low heat exchange efficiency, high outlet temperature, and easy occurrence of high temperature corrosion and tube rupture in the boiler in related technologies.

[0005] This utility model also provides a boiler system.

[0006] The waste heat boiler equipment of this utility model includes:

[0007] A channel, the channel being adapted to allow the flue gas for heat recovery to pass through and to guide the flow of the flue gas;

[0008] A superheater is disposed within the channel and is adapted to recover heat from the flue gas within the channel;

[0009] First soot blower

[0010] in:

[0011] The first soot blower is disposed in the channel, the first soot blower is located upstream of the superheater along the conveying direction of the channel, and the first soot blower is adapted to blow soot onto the wall surface inside the channel;

[0012] The channel includes a first channel section, a second channel section, and a third channel section arranged sequentially along the conveying direction. The first soot blower is disposed in the first channel section and / or the second channel section, and the superheater is disposed in the third channel section.

[0013] The bottom of the first channel section, the second channel section, and the third channel section are all equipped with ash hoppers;

[0014] The interior of the first channel section and the second channel section is a water-cooled wall tube, and the first soot blower is adapted to blow soot from the water-cooled wall tube.

[0015] In some technical solutions, the first soot blower is an acoustic soot blower.

[0016] In some technical solutions, the acoustic soot blower and the channel wall of the channel are welded and fixed.

[0017] In some technical solutions, the gas source for the acoustic soot blower is nitrogen, carbon dioxide, or an inert gas.

[0018] In some technical solutions, there are multiple first soot blowers;

[0019] At least some of the first soot blowers are arranged at intervals along the conveying direction of the channel; and / or, at least some of the first soot blowers are arranged at intervals circumferentially along the channel.

[0020] In some technical solutions, the first channel segment, the second channel segment, and the third channel segment extend in the same direction, the flue gas in the first channel segment and the third channel segment are transported in the same direction, and the flue gas in the second channel segment is transported in the opposite direction to the flue gas in the first channel segment and the third channel segment.

[0021] In some technical solutions, the first channel segment, the second channel segment, and the third channel segment are all arranged vertically. The flue gas is conveyed in the first channel segment and the third channel segment in a downward direction, while the flue gas is conveyed in the second channel segment in a downward direction.

[0022] In some technical solutions, the ash hopper is equipped with at least one level sensor, which is used to monitor the material level inside the ash hopper.

[0023] In some technical solutions, a first temperature sensor is installed at both the inlet and outlet of the first channel segment, and the blowing frequency of the first soot blower on the first channel segment is adjusted according to the temperature difference monitored by the first temperature sensors at the inlet and outlet of the first channel segment; and / or,

[0024] A second temperature sensor is installed at both the inlet and outlet of the second channel section. The blowing frequency of the first soot blower on the second channel section is adjusted according to the temperature difference monitored by the second temperature sensor at the inlet and outlet of the second channel section.

[0025] In some technical solutions, the device further includes an evaporator connected to the outlet of the channel, the evaporator being adapted to cool the flue gas flowing out of the channel.

[0026] In some technical solutions, the device further includes multiple second soot blowers, which are provided at both the superheater and the evaporator.

[0027] In some technical solutions, the second soot blower includes:

[0028] A soot blowing pipe passes through the channel wall of the channel and extends into the superheater. The soot blowing pipe is provided with a plurality of openings for the soot blowing medium entering the soot blowing pipe to flow out of the soot blowing pipe.

[0029] An isolation pipe is connected to the portion of the soot blowing pipe located outside the channel wall, and the isolation pipe is adapted to blow isolation gas to the connection position between the second soot blower and the channel wall.

[0030] In some technical solutions, the second sootblower is a steam sootblower, the second sootblower is connected to the outlet of the superheater, and the sootblowing medium of the second sootblower is superheated steam output from the superheater.

[0031] In some technical solutions, the device further includes a control device disposed between the superheater and the second soot blower, the control device being adapted to regulate the amount of superheated steam supplied by the superheater to the second soot blower.

[0032] In some technical solutions, there are multiple superheaters, and the multiple superheaters include a first superheater, a second superheater, and a third superheater arranged sequentially along the conveying direction of the channel;

[0033] The temperature of the second superheater is higher than that of the first superheater, and the temperature of the first superheater is higher than that of the third superheater;

[0034] The control device is connected to the outlet of the first superheater.

[0035] In some technical solutions, there are two evaporators, which are arranged in parallel, and one of the evaporators is a standby evaporator.

[0036] In some technical solutions, the first soot blower is connected to a sealing gas pipe, which is connected to the outer portion of the channel wall of the first soot blower in the channel, and the sealing gas pipe is adapted to blow sealing gas to the connection position between the first soot blower and the channel wall.

[0037] The boiler system of this utility model includes the waste heat boiler equipment described in any of the above technical solutions.

[0038] Beneficial effects: The technical solution of this utility model can solve the problem of serious ash accumulation in waste heat boilers in related technologies, thereby avoiding problems such as low heat exchange efficiency, high outlet temperature, and easy occurrence of high temperature corrosion and tube rupture in local boilers.

[0039] Secondly, it also has good sealing properties, which prevents the leakage of syngas and other substances, thus ensuring the safety of production.

[0040] In addition, by setting up multiple channel sections, each with an ash hopper at the bottom, the multiple channel sections extend the flow path of the flue gas and allow each channel section to be cleaned independently, thereby improving the cleaning efficiency and effect of the entire channel.

[0041] Water-cooled wall tubes are installed in multiple channel sections, and heat recovery from the flue gas can be achieved through multiple water-cooled wall tubes, thereby improving the efficiency and effect of heat recovery from the flue gas. Attached Figure Description

[0042] The following description and accompanying drawings will better aid in understanding these and other features and advantages of the various embodiments disclosed herein, wherein the same reference numerals in the drawings always denote the same parts, wherein:

[0043] Figure 1 This is a schematic diagram of the overall structure of a waste heat boiler device according to an embodiment of the present invention;

[0044] Figure 2 for Figure 1 A schematic diagram of the second soot blower in a medium-temperature waste heat boiler.

[0045] Figure label:

[0046] 1-Channel; 11-First channel section; 12-Second channel section; 13-Third channel section; 14-Channel wall; 101-Sealing gas pipe;

[0047] 2-Superheater; 21-First superheater; 22-Second superheater; 23-Third superheater;

[0048] 3-First soot blower; 4-Ash hopper; 5-Material level sensor;

[0049] 61 - First temperature sensor; 62 - Second temperature sensor;

[0050] 7-Evaporator;

[0051] 8-Second soot blower; 81-Soot blowing pipe; 811-Opening; 82-Soot blowing medium; 83-Isolation gas;

[0052] 9-Control device. Detailed Implementation

[0053] The technical solution of this utility model will be further described in detail below through embodiments and in conjunction with the accompanying drawings. In this specification, the same or similar reference numerals indicate the same or similar components. The following description of the embodiments of this utility model with reference to the accompanying drawings is intended to explain the overall inventive concept of this utility model and should not be construed as a limitation thereof.

[0054] It should be noted that this utility model is based on the following facts, problems, and discoveries:

[0055] Currently, the high-temperature dust-laden gas produced by the positive pressure circulating fluidized bed biomass gasifier enters the waste heat boiler to recover heat. Because the high-temperature dust-laden gas contains tar, alkali metals (potassium, sodium), chlorine, silicon and ash, it is easy for ash to adhere and accumulate on the heating surfaces such as superheaters, economizers, and convection tube bundles. This will significantly reduce heat exchange efficiency, cause the boiler outlet temperature to exceed the limit, affect the stable operation of downstream equipment, and when the ash accumulation inside the boiler is severe, it will cause local high-temperature corrosion and tube rupture.

[0056] Secondly, since the gas products of biomass circulating fluidized bed contain components such as CO, H2, CO2, and CH4, the positive pressure sealing requirements of the currently used rotary telescopic sootblower are relatively high, the sealing gas consumption is too large, and a large amount of inert gas enters the system, affecting the composition of the high-temperature dust-containing gas. In severe cases, it affects the purity of subsequent products. Moreover, the rotary telescopic sootblower is also prone to syngas leakage during excessive operation, affecting the safe and stable operation of the equipment.

[0057] Based on the above, this utility model proposes a waste heat boiler device.

[0058] like Figure 1 As shown, the waste heat boiler equipment of this utility model includes a channel 1, a superheater 2, and a first soot blower 3.

[0059] Channel 1 is adapted to allow and guide the flow of flue gas for heat recovery. For example, as... Figure 1 As shown, channel 1 may include multiple vertically extending channel 1 segments, which can be arranged sequentially in the left and right directions. The inlet of channel 1 can be located at the top of the leftmost channel 1 segment, and the outlet of channel 1 can be located at the bottom of the rightmost channel 1 segment.

[0060] When in use, the high-temperature syngas and other flue gas produced by the biomass gasification furnace can be introduced into channel 1 through the inlet of channel 1, and then the flue gas can flow along channel 1 and finally be discharged through the outlet of channel 1.

[0061] Superheater 2 is installed inside channel 1, and superheater 2 is adapted to recover heat from the flue gas inside channel 1. For example, as Figure 1As shown, multiple superheaters 2 can be provided. For example, there can be two or three superheaters 2. Superheaters 2 can recover heat from the flue gas in channel 1, thereby realizing the recovery and utilization of heat.

[0062] The first soot blower 3 is disposed in the channel 1, the first soot blower 3 is located upstream of the superheater 2 along the conveying direction of the channel 1, and the first soot blower 3 is adapted to blow soot onto the wall surface inside the channel 1.

[0063] For example, the first soot blower 3 is an acoustic soot blower. Multiple first soot blowers 3 can be provided, and these multiple first soot blowers 3 can be evenly distributed on the channel wall 14 of the channel 1. Specifically, such as... Figure 1 As shown, along the flow direction of the flue gas in the channel 1, the aforementioned plurality of first soot blowers 3 can be evenly distributed upstream of the superheater 2.

[0064] like Figure 1 As shown, the first soot blower 3 requires continuous blowing of sealing gas. The sealing gas serves as the air source for the first soot blower 3, preventing dust accumulation inside the blower's nozzle and preventing syngas leakage when not blowing soot. The sealing gas pressure is 10-15 kPa higher than the syngas pressure, and a pressure reducing valve and a manual valve are installed on the sealing gas pipeline 101 to regulate the flow rate.

[0065] The aforementioned sealing gas pipe 101 can be connected to the portion of the first soot blower 3 located outside the channel 1. The sealing gas pipe 101 is connected to the first soot blower 3, thereby satisfying the need to introduce sealing gas into the first soot blower 3 through the sealing gas pipe 101.

[0066] In this invention, by setting up a first soot blower 3, the first soot blower 3 can realize the soot blowing operation in the channel 1, thereby avoiding the situation where tar, alkali metals (potassium, sodium), chlorine, silicon and ash in the flue gas easily adhere to the channel wall 14 of the channel 1. This avoids problems such as reduced heat exchange efficiency of the waste heat boiler, excessive outlet temperature, local high temperature corrosion and tube rupture of the boiler caused by the adhesion of ash to the channel wall 14.

[0067] In some embodiments, the acoustic sootblower and the channel wall 14 of the channel 1 are welded together. For example, the flange sleeve of the acoustic sootblower can be firmly welded to the inner wall of the channel wall 14, thereby ensuring the sealing of the connection and preventing the leakage of syngas.

[0068] In some embodiments, the gas source for the acoustic sootblower is nitrogen, carbon dioxide, or an inert gas. These gases have good stability, thereby reducing the impact on the syngas.

[0069] In some embodiments, there are multiple first soot blowers 3, and at least some of the first soot blowers 3 are arranged at intervals along the conveying direction of the channel 1. For example, as Figure 1 As shown, the conveying direction can be the up and down direction of channel 1. Multiple first soot blowers 3 can be arranged at intervals along the up and down direction of the channel 1. Specifically, multiple first soot blowers 3 can be arranged in layers, and multiple first soot blowers 3 can be arranged in 3 to 6 layers.

[0070] In some embodiments, at least a portion of the first soot blowers 3 are arranged at circumferential intervals along the channel 1. For example, as... Figure 1 As shown, multiple first soot blowers 3 can be arranged at intervals along the circumference of the channel 1 section, that is, each layer can include multiple first soot blowers 3, thereby enabling soot blowing operations to be performed in all directions of the circumference of the channel 1.

[0071] In some embodiments, the channel 1 includes a first channel segment 11, a second channel segment 12 and a third channel segment 13 arranged sequentially along the conveying direction, a first soot blower 3 is disposed in the first channel segment 11 and / or the second channel segment 12, and a superheater 2 is disposed in the third channel segment 13.

[0072] For example, such as Figure 1 As shown, channel 1 may include three channel 1 segments, namely the first channel segment 11, the second channel segment 12, and the third channel segment 13. The second channel segment 12 may be located between the first channel segment 11 and the third channel segment 13, and the second channel segment 12 may connect the first channel segment 11 and the third channel segment 13.

[0073] Multiple first soot blowers 3 can be installed on the channel walls 14 of the first channel section 11 and the second channel section 12, while the superheater 2 is only arranged in the third channel section 13.

[0074] In some embodiments, the first channel segment 11, the second channel segment 12, and the third channel segment 13 extend in the same direction, the flue gas in the first channel segment 11 and the third channel segment 13 are transported in the same direction, and the flue gas in the second channel segment 12 is transported in the opposite direction to the flue gas in the first channel segment 11 and the third channel segment 13.

[0075] For example, such as Figure 1 As shown, the first channel segment 11, the second channel segment 12, and the third channel segment 13 are all arranged vertically. The inlet of the first channel segment 11 is located at the top of the first channel segment 11, and the outlet of the first channel segment 11 is located at the bottom of the first channel segment 11. The inlet of the second channel segment 12 is located at the bottom of the second channel segment 12, and the outlet of the second channel segment 12 is located at the top of the second channel segment 12. The inlet of the third channel segment 13 is located at the top of the third channel segment 13, and the outlet of the third channel segment 13 is located at the bottom of the third channel segment 13.

[0076] The outlet of the first channel segment 11 is connected to the inlet of the second channel segment 12, and the outlet of the second channel segment 12 is connected to the inlet of the third channel segment 13.

[0077] The flue gas in the first channel section 11 and the third channel section 13 is transported from top to bottom, while the flue gas in the second channel section 12 is transported from bottom to top.

[0078] The bottom of the first channel section 11, the second channel section 12, and the third channel section 13 are all equipped with ash hoppers 4. For example, as Figure 1 As shown, the bottom of the first channel segment 11, the second channel segment 12 and the third channel segment 13 are all connected to an ash hopper 4.

[0079] In use, each ash hopper 4 can collect fly ash from the corresponding channel section 1, and then the fly ash can be discharged through the ash discharge pipe at the bottom of the ash hopper 4. The ash discharge pipe can be connected to a water-cooled spiral or a cold ash tank.

[0080] In some embodiments, the ash hopper 4 is provided with at least one level sensor 5, which is used to monitor the material level in the ash hopper 4.

[0081] For example, such as Figure 1 As shown, the material level sensor 5 can be a temperature sensor for detecting temperature. Each ash hopper 4 can be equipped with two temperature sensors, which can be arranged at intervals in the vertical direction. The material level in the ash hopper 4 can be detected through these two temperature sensors.

[0082] In some embodiments, a first temperature sensor 61 is provided at both the inlet and outlet of the first channel segment 11, and the blowing frequency of the first soot blower 3 on the first channel segment 11 is adjusted according to the temperature difference monitored by the first temperature sensor 61 at the inlet and outlet of the first channel segment 11.

[0083] For example, such as Figure 1 As shown, a first temperature sensor 61 can be installed at both the inlet and outlet of the first channel section 11. In use, the temperature value obtained by these two first temperature sensors 61 can be used to calculate the temperature difference between the inlet and outlet. Then, based on the obtained temperature difference, the blowing frequency of each first soot blower 3 in the first channel section 11 can be adjusted.

[0084] Specifically, if the temperature difference is large, it indicates that the heat exchange effect is good; if the temperature difference is small, it indicates that the heat exchange effect is poor. At this time, fly ash adheres and the blowing frequency of each first soot blower 3 needs to be increased.

[0085] In some embodiments, a second temperature sensor 62 is provided at both the inlet and outlet of the second channel segment 12, and the blowing frequency of the first soot blower 3 on the second channel segment 12 is adjusted according to the temperature difference monitored by the second temperature sensor 62 at the inlet and outlet of the second channel segment 12.

[0086] For example, such as Figure 1 As shown, a second temperature sensor 62 can be installed at both the inlet and outlet of the second channel section 12. In use, the temperature value can be obtained through these two second temperature sensors 62 to calculate the temperature difference between the inlet and outlet. Then, based on the obtained temperature difference, the blowing frequency of each second soot blower 8 in the second channel section 12 can be adjusted.

[0087] Specifically, if the temperature difference is large, it indicates that the heat exchange effect is good; if the temperature difference is small, it indicates that the heat exchange effect is poor. At this time, fly ash adheres and the blowing frequency of each second soot blower 8 needs to be increased.

[0088] In some embodiments, the interior of the first channel section 11 and the second channel section 12 is a water-cooled wall tube, and the first soot blower 3 is adapted to blow soot from the water-cooled wall tube. For example, the channel walls 14 of both the first channel section 11 and the second channel section 12 can be provided with water-cooled wall tubes, thereby enabling the recovery of heat from the flue gas. The aforementioned first soot blowers 3 can perform soot blowing operations on the water-cooled wall tubes, improving the situation of ash accumulation and adhesion on the water-cooled wall tubes.

[0089] In some embodiments, the device further includes an evaporator 7 connected to the outlet of the channel 1, the evaporator 7 being adapted to cool the flue gas flowing out of the channel 1.

[0090] For example, such as Figure 1 As shown, the evaporator 7 can be located on the right side of the channel 1, and specifically connected to the outlet of the third channel section 13 mentioned above. The evaporator 7 can further recover the heat from the flue gas, thereby avoiding energy waste and improving heat utilization efficiency.

[0091] In some embodiments, the device further includes a plurality of second soot blowers 8, with second soot blowers 8 provided at both the superheater 2 and the evaporator 7. For example, as Figure 1 As shown, each superheater 2 and evaporator 7 is equipped with a second soot blower 8, which can perform soot blowing operations on the superheater 2 and evaporator 7, thereby preventing ash from accumulating and sticking to these components.

[0092] In some embodiments, the second soot blower 8 includes a soot blowing pipe 81 and an isolation pipe.

[0093] The soot blowing pipe 81 passes through the channel wall 14 of the channel 1 and extends into the superheater 2. The soot blowing pipe 81 is provided with a plurality of openings 811, which are used to allow the soot blowing medium 82 that enters the soot blowing pipe 81 to flow out of the soot blowing pipe 81.

[0094] For example, such as Figure 2 As shown, the sootblowing pipe 81 can be a straight circular pipe. The channel wall 14 and the evaporator 7 can be provided with mounting holes for the sootblowing pipe 81 to extend into. The outer end of the sootblowing pipe 81 can be connected and fixed to the channel wall 14 via a flange or similar means. The sootblowing pipe 81 can have a plurality of openings 811 evenly distributed on it, and these openings 811 can be arranged at intervals along the axial and circumferential directions of the sootblowing pipe 81. This satisfies the need for sootblowing medium 82 to be sprayed from various directions, ensuring the quality of sootblowing.

[0095] The isolation pipe is connected to the portion of the soot blowing pipe 81 located outside the channel wall 14. The isolation pipe is adapted to blow isolation gas 83 to the connection position between the second soot blower 8 and the channel wall 14.

[0096] For example, such as Figure 2 As shown, the outer end of the soot blowing pipe 81 can be located outside the channel wall 14 and the evaporator 7. The isolation pipe can be fixed to the outer end of the soot blowing pipe 81 by means of plugging or the like. The outlet of the isolation pipe can face the connection position of the soot blowing pipe 81 and the channel wall 14, etc. The isolation pipe can be connected to the soot blowing pipe 81.

[0097] In use, isolation gas 83 can be introduced into the isolation pipe, so that the isolation gas 83 ejected from the outlet of the isolation pipe can be blown towards the connection position between the soot blowing pipe 81 and the channel wall 14. The isolation gas 83 can achieve an airtight seal at this position, preventing the leakage of syngas and other flue gases. When soot blowing is not performed, the introduced isolation gas 83 can also flow along the soot blowing pipe to the opening 811, so that the introduced isolation gas 83 can prevent the opening 811 from being blocked by ash in the syngas.

[0098] In some embodiments, the second soot blower 8 is a steam soot blower, the second soot blower 8 is connected to the outlet of the superheater 2, and the soot blowing medium 82 of the second soot blower 8 is superheated steam output from the superheater 2.

[0099] For example, such as Figure 1 As shown, each of the above-mentioned second soot blowers 8 can be connected to the outlet of a superheater 2 at the same time. The superheated steam flowing out from the superheater 2 can be directly introduced into each superheater 2 and evaporator 7 by the second soot blower 8, thereby realizing the soot blowing operation.

[0100] This allows for the use of locally sourced materials, avoiding the need for additional gas supply facilities. It also facilitates a simplified layout of the overall structure.

[0101] In some embodiments, the device further includes a control device 9 disposed between the superheater 2 and the second soot blower 8, the control device 9 being adapted to regulate the amount of superheated steam supplied by the superheater 2 to the second soot blower 8.

[0102] For example, such as Figure 1 As shown, the control device 9 may include components such as valves and pressure gauges. The control device 9 may be installed between the superheater 2, which supplies superheated steam to each of the second sootblower 8, and the multiple second sootblower 8. By means of the control device 9, the amount of superheated steam supplied to the second sootblower 8 can be regulated, thereby enabling the sootblowing operation of the second sootblower 8 to be adjustable.

[0103] In some embodiments, there are multiple superheaters 2, including a first superheater 21, a second superheater 22 and a third superheater 23 arranged sequentially along the conveying direction of the channel 1. The temperature of the second superheater 22 is higher than that of the first superheater 21, and the temperature of the first superheater 21 is higher than that of the third superheater 23.

[0104] For example, such as Figure 1 As shown, the first superheater 21 can be a medium-temperature superheater, the second superheater 22 can be a high-temperature superheater, and the third superheater 23 can be a low-temperature superheater. The medium-temperature superheater, the high-temperature superheater, and the low-temperature superheater can be arranged at intervals along the vertical extension direction of the third channel section 13. In use, the flue gas in the third channel section 13 can flow through the first superheater 21, the second superheater 22, and the third superheater 23 in sequence.

[0105] The control device 9 is connected to the outlet of the first superheater 21. For example, as Figure 1 As shown, the control device 9 can be located on the right side of the third channel section 13. The outlet of the superheated steam of the first superheater 21 can be directly connected to the control device 9, and then the superheated steam flowing out of the control device 9 can be diverted to each of the second soot blowers 8.

[0106] In some embodiments, such as Figure 1 As shown, there are two evaporators 7, arranged in parallel, with one evaporator 7 serving as a standby evaporator. Therefore, when one evaporator 7 needs maintenance or oil cleaning, the other evaporator 7 can be started to maintain the continuous operation of the waste heat boiler equipment, thus ensuring operational continuity.

[0107] In some embodiments, such as Figure 1 As shown, the third superheater 23 can be supplied with saturated steam C from the steam drum or boiler feedwater B from the low-temperature economizer, thereby achieving heat exchange with flue gas such as syngas.

[0108] In some embodiments, such as Figure 1As shown, the first superheater 21 can be supplied with superheated steam from the outlet of the third superheater 23 or saturated steam C from the steam drum, and a portion of the superheated steam D can also be discharged through the outlet on the third channel section.

[0109] In some embodiments, such as Figure 1 As shown, the evaporator 7 can be connected to a steam drum downcomer E and a steam drum riser F.

[0110] In some embodiments, a pneumatic valve and an electric blind valve may also be installed on the pipeline connecting the third channel section 13 and the evaporator 7. This allows for the cutoff of flue gas to the evaporator and the switching between the main evaporator and the standby evaporator.

[0111] In some embodiments, multiple temperature sensors may also be provided on the third channel segment 13, thereby adjusting the blowing frequency of the corresponding second soot blower by measuring the difference between the upstream and downstream temperature detection values ​​of each superheater and evaporator.

[0112] The boiler system of this utility model is described below.

[0113] The boiler system of this utility model includes the waste heat boiler equipment described in any of the above embodiments. The boiler system may include a biomass circulating fluidized bed gasifier, which may be connected to the inlet of the aforementioned channel.

[0114] The following describes a specific example of the waste heat boiler equipment of this utility model.

[0115] The waste heat boiler is a membrane wall water tube boiler, comprising a first channel section 11, a second channel section 12, and a third channel section 13. The first and second channel sections 11 and 12 are cavities with water-cooled walls on all four sides. The third channel section 13 also has water-cooled walls on all four sides, and three layers of serpentine heat exchange tubes are arranged from top to bottom within it, serving as a medium-temperature superheater, a high-temperature superheater, and a low-temperature superheater.

[0116] The outlet of the low-temperature superheater is connected to the main evaporator and the standby evaporator. The main evaporator and the standby evaporator are connected in parallel. Considering that one evaporator 7 is blocked, it can be switched to another evaporator for operation without stopping the machine for maintenance.

[0117] The biomass syngas flow path sequentially through the first channel section 11, the second channel section 12, the third channel section 13, and the main evaporator 7 before entering the high-temperature dust collector. The first and second channel sections 11 and 12 are equipped with multi-layer acoustic soot blowers, while each layer of the third channel section 13 is equipped with a fixed steam soot blower. This achieves graded soot removal, preventing wall adhesion, which affects heat exchange efficiency and normal operation of the equipment. This invention provides a waste heat boiler soot blowing system.

[0118] like Figure 1As shown, the positive pressure soot blowing system includes: a first channel section 11, an ash hopper 4, a second channel section 12, an acoustic soot blower, an acoustic air source, a medium-temperature superheater, a high-temperature superheater, a low-temperature superheater, an evaporator 7, pneumatic valves, a control system, a soot blowing pipe, an isolation gas 83, a fixed steam soot blower, and an outlet pipe.

[0119] The first channel section 11 is connected to the outlet of the biomass circulating fluidized bed gasifier; the interior is a water-cooled wall tube that absorbs the heat carried by the biomass syngas. The ash hopper 4 is below the first channel section 11 to collect the fly ash carried by the syngas and settled. Thermometers are installed above and below the ash hopper 4 to monitor the ash level. Below the ash hopper 4 is an ash discharge pipe that is connected to a water-cooled spiral or a cold ash tank.

[0120] Acoustic soot blowers are installed on the front, left, and right walls of the first channel section 11. The gas source for the acoustic soot blowers is inert gas, nitrogen, or carbon dioxide. The acoustic soot blowers are arranged in 3 to 6 layers vertically in the first channel section 11, with a blowing frequency of 1 to 5 times / hour. The blowing frequency can also be adjusted according to the temperature difference between the inlet and outlet of the first channel section 11 to ensure the soot blowing and heat exchange effects. The flange sleeves of the acoustic soot blowers are firmly welded to the furnace wall to ensure that the biomass syngas does not leak out.

[0121] The second channel section 12 connects to the first channel section 11 and contains water-cooled wall tubes to further cool the biomass syngas. The ash hopper 4 collects the settled fly ash carried by the syngas below the second channel section 12. Thermometers are installed above and below the ash hopper 4 to monitor the ash level. An ash discharge pipe connects to the bottom of the ash hopper 4, which in turn connects to a water-cooled spiral or cold ash hopper. Acoustic soot blowers are installed on the left and right walls of the first channel section 11, using inert gas, nitrogen, or carbon dioxide as the gas source. The acoustic soot blowers are arranged in 3-6 layers above and below the second channel section 12, with a blowing frequency of 1-5 times / hour. The blowing frequency can also be adjusted according to the temperature difference between the inlet and outlet thermometers of the first channel section 11 to ensure effective soot blowing and heat exchange.

[0122] The medium-temperature superheater, high-temperature superheater, and low-temperature superheater are installed in the third channel section 13 of the boiler. After passing through the above three devices, the temperature of the biomass syngas is further reduced. The biomass syngas enters the main evaporator, which lowers the temperature of the syngas to 380°C. The outlet pipe of the main steamer enters the high-temperature dust collector.

[0123] The internal components of the medium-temperature superheater, high-temperature superheater, low-temperature superheater, and main and standby evaporators are all serpentine coils. Ash from biomass gas tends to accumulate on the serpentine coils. Each of the medium-temperature superheater, high-temperature superheater, low-temperature superheater, and main and standby evaporators is equipped with a fixed steam soot blower.

[0124] like Figure 2As shown, the stationary steam sootblower consists of a sootblowing pipe 81 and an isolation air supply. The sootblowing pipe 81 is inserted into the upper part of the heating surface of the medium-temperature superheater, high-temperature superheater, low-temperature superheater, and main and standby evaporators. The sootblowing pipe of the stationary steam sootblower is made of wear-resistant high-temperature material. 15 to 30 small holes with a diameter of 3 to 8 mm are opened on the upper part of the sootblowing pipe. The small holes are evenly distributed along the sootblowing pipe, and the direction of the openings 811 can cover 100% of the boiler heating surface.

[0125] The steam source for the soot blowing pipe is superheated steam from the outlet of the medium-temperature superheater, which enters the soot blowing pipe through the control system to blow soot onto the boiler heating surface. The soot blowing pipe has a solenoid valve that is remotely controlled by a PLC or DCS. It is purged once every 2 to 8 hours. The purging effect can be judged by the remote thermometers set up upstream and downstream of the medium-temperature superheater, high-temperature superheater, low-temperature superheater, and main and standby evaporators.

[0126] The control system consists of an electric on / off valve, a self-regulating pressure reducing valve, and a pressure gauge. The fixed steam soot blower uses a steam source pressure of 1.5~2.0 MPaG and a temperature higher than 280℃ to prevent low-temperature steam from entering the boiler heating surface and condensing, causing dust to adhere to the heating surface and affecting the heat exchange effect.

[0127] The isolation air is an inert gas such as nitrogen or carbon dioxide, which needs to be continuously introduced and the pressure is 20~50 kPa higher than that of the waste heat boiler to prevent the biomass syngas in the waste heat boiler system from leaking out.

[0128] It should be noted that, in this utility model, each numerical range, except for explicitly stated not to include endpoint values, can be either endpoint values ​​or the median value of each numerical range. Furthermore, the specific numerical values ​​in this utility model are not intended to limit the corresponding dimensional parameters in this utility model, and all permissible values ​​are within the protection scope of this utility model.

[0129] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that variations may be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A waste heat boiler device, comprising: A channel, the channel being adapted to allow the flue gas for heat recovery to pass through and to guide the flow of the flue gas; A superheater is disposed within the channel and is adapted to recover heat from the flue gas within the channel; First soot blower in: The first soot blower is disposed in the channel, the first soot blower is located upstream of the superheater along the conveying direction of the channel, and the first soot blower is adapted to blow soot onto the wall surface inside the channel; The channel includes a first channel section, a second channel section, and a third channel section arranged sequentially along the conveying direction. The first soot blower is disposed in the first channel section and / or the second channel section, and the superheater is disposed in the third channel section. The bottom of the first channel section, the second channel section, and the third channel section are all equipped with ash hoppers; The interior of the first channel section and the second channel section is a water-cooled wall tube, and the first soot blower is adapted to blow soot from the water-cooled wall tube.

2. The waste heat boiler equipment according to claim 1, wherein: The first soot blower is an acoustic soot blower.

3. The waste heat boiler equipment according to claim 2, wherein: The acoustic soot blower is welded and fixed to the channel wall.

4. The waste heat boiler equipment according to claim 2, wherein: The gas source for the acoustic soot blower is nitrogen, carbon dioxide, or an inert gas.

5. The waste heat boiler equipment according to claim 1, wherein: There are multiple first soot blowers; At least some of the first soot blowers are arranged at intervals along the conveying direction of the channel; and / or, at least some of the first soot blowers are arranged at intervals circumferentially along the channel.

6. The waste heat boiler equipment according to claim 1, wherein: The first channel segment, the second channel segment, and the third channel segment extend in the same direction. The flue gas in the first channel segment and the third channel segment is transported in the same direction. The flue gas in the second channel segment is transported in the opposite direction to the flue gas in the first channel segment and the third channel segment.

7. The waste heat boiler equipment according to claim 6, wherein: The first channel segment, the second channel segment, and the third channel segment are all arranged vertically. The flue gas in the first channel segment and the third channel segment is transported from top to bottom, while the flue gas in the second channel segment is transported from bottom to top.

8. The waste heat boiler equipment according to claim 7, wherein: The ash hopper is equipped with at least one level sensor, which is used to monitor the material level inside the ash hopper.

9. The waste heat boiler equipment according to claim 1, wherein: A first temperature sensor is installed at both the inlet and outlet of the first channel segment. The blowing frequency of the first soot blower on the first channel segment is adjusted according to the temperature difference monitored by the first temperature sensors at the inlet and outlet of the first channel segment; and / or, A second temperature sensor is installed at both the inlet and outlet of the second channel section. The blowing frequency of the first soot blower on the second channel section is adjusted according to the temperature difference monitored by the second temperature sensor at the inlet and outlet of the second channel section.

10. The waste heat boiler equipment according to claim 1, wherein: The device also includes an evaporator connected to the outlet of the channel, the evaporator being adapted to cool the flue gas flowing out of the channel.

11. The waste heat boiler equipment according to claim 10, wherein: The device also includes a plurality of second soot blowers, which are provided at both the superheater and the evaporator.

12. The waste heat boiler equipment according to claim 11, wherein: The second soot blower includes: A soot blowing pipe passes through the channel wall of the channel and extends into the superheater. The soot blowing pipe is provided with a plurality of openings for the soot blowing medium entering the soot blowing pipe to flow out of the soot blowing pipe. An isolation pipe is connected to the portion of the soot blowing pipe located outside the channel wall, and the isolation pipe is adapted to blow isolation gas to the connection position between the second soot blower and the channel wall.

13. The waste heat boiler equipment according to claim 12, wherein: The second soot blower is a steam soot blower, and the second soot blower is connected to the outlet of the superheater. The soot blowing medium of the second soot blower is superheated steam output from the superheater.

14. The waste heat boiler equipment according to claim 13, wherein: The equipment also includes a control device disposed between the superheater and the second soot blower, the control device being adapted to regulate the amount of superheated steam supplied by the superheater to the second soot blower.

15. The waste heat boiler equipment according to claim 14, wherein: There are multiple superheaters, and the multiple superheaters include a first superheater, a second superheater and a third superheater arranged sequentially along the conveying direction of the channel; The temperature of the second superheater is higher than that of the first superheater, and the temperature of the first superheater is higher than that of the third superheater; The control device is connected to the outlet of the first superheater.

16. The waste heat boiler equipment according to claim 10, wherein: There are two evaporators, which are arranged in parallel, and one of the evaporators is a standby evaporator.

17. The waste heat boiler equipment according to any one of claims 1-16, wherein: The first soot blower is connected to a sealing gas pipe, which is connected to the outer portion of the channel wall of the first soot blower in the channel. The sealing gas pipe is adapted to blow sealing gas to the connection position between the first soot blower and the channel wall.

18. A boiler system comprising a waste heat boiler device according to any one of claims 1-17.

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