Novel biomass boiler dust removal and denitration system

Abstract

The utility model discloses a novel biomass boiler dust removal and denitration system, which relates to the technical field of boiler dust removal and denitration and comprises a biomass boiler main body, a boiler tail flue, an SCR (selective catalytic reduction) denitration reactor and an auxiliary mechanism. When the novel biomass boiler dust removal and denitration system is used, the high-temperature filter bag dust remover is arranged before a traditional denitration process, and then dust is removed, so that the problem that alkali metal components in dust are poisoned by a denitration catalyst can be solved, the problem that the temperature of flue gas needs to be increased again in an original post-denitration process to meet the denitration temperature is solved, and the service life of the flue gas is prolonged. The flue gas is filtered again through the auxiliary mechanism, residual impurities in the flue gas are prevented from being discharged into air together, and the flue gas treatment quality is improved, so that when a biomass boiler dust removal and denitration system is used, the flue gas is prevented from being discharged into the flue gas, and the dust removal and denitration efficiency is improved. The effects of preventing the denitration catalyst from poisoning and improving the flue gas treatment quality are achieved.

Description

Technical Field

[0001] This utility model relates to the field of boiler dust removal and denitrification technology, specifically a novel biomass boiler dust removal and denitrification system. Background Technology

[0002] Boiler dust removal and denitrification refers to the treatment of smoke and nitrogen oxides generated during boiler combustion to reduce their environmental pollution. Currently, the most efficient and stable denitrification process for boilers is the SCR (Selective Catalytic Reduction) process. SCR denitrification mainly relies on the action of a catalyst, which lowers the temperature window for the reaction between the reducing agent ammonia and NOx, and can even complete denitrification at lower temperatures. Biomass boiler dust removal and denitrification systems are used to treat the flue gas emitted by biomass boilers to reduce pollutants such as particulate matter and nitrogen oxides. Biomass boilers also have a more complex fuel structure than coal-fired boilers.

[0003] According to announcement number CN219083142U, a biomass boiler dust removal, desulfurization, and denitrification system includes a biomass boiler, a sodium bicarbonate powder conveying device, a high-temperature resistant bag filter, a denitrification reactor, a medium-low temperature denitrification catalyst, an ammonia water conveying device, a primary air duct, an exhaust fan, and a chimney. One end of the boiler economizer is connected to the high-temperature resistant bag filter via flue duct one, the sodium bicarbonate powder conveying device is connected to flue duct one, one end of flue duct two is connected to the high-temperature resistant bag filter, and the other end of the denitrification reactor is connected to the boiler air preheater via flue duct three. The medium-low temperature denitrification catalyst is located inside the denitrification reactor, and the ammonia water conveying device is connected to the denitrification reactor. This dust removal, desulfurization, and denitrification system sequentially installs sodium bicarbonate desulfurization, a high-temperature resistant bag filter, and a denitrification device after the boiler economizer to remove SO2, particulate matter, and NOx from the flue gas. Using sodium bicarbonate for desulfurization is water-free, simple to operate, has low investment costs, and requires little floor space.

[0004] However, biomass fuel itself contains alkaline substances, which, after combustion, form fly ash that enters the SCR system, adsorbs on the surface of the SCR catalyst or blocks the catalyst pores, and reacts with the active components on the catalyst surface, causing catalyst poisoning and deactivation. Secondly, because the flue gas temperature at the tail end of the biomass boiler is low and the moisture content is high, if a catalyst is installed at the tail end of the boiler, water will adsorb on the active sites on the catalyst surface, reducing the adsorption sites for ammonia, thereby reducing the denitrification reaction rate and denitrification activity. Under low temperature conditions, the higher moisture content makes fly ash more likely to adhere to the catalyst surface, thus leading to a more rapid alkaline poisoning phenomenon. Utility Model Content

[0005] The purpose of this invention is to provide a novel dust removal and denitrification system for biomass boilers to solve the problems mentioned in the background.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a novel biomass boiler dust removal and denitrification system, comprising a biomass boiler body, a boiler tail flue, an SCR denitrification reactor, and auxiliary mechanisms. The boiler tail flue is connected to one side of the outer wall of the biomass boiler body, and a high-temperature bag filter dust collector is connected to the boiler tail flue via a flue gas pipe. The high-temperature bag filter dust collector is connected to the SCR denitrification reactor via the flue. An ammonia injection device is installed on the outer wall of the flue. The SCR denitrification reactor is connected to a boiler air preheater via a transmission pipe, and an air inlet pipe is connected to one side of the bottom of the boiler air preheater. The boiler air preheater is connected to the biomass boiler body via a return gas pipe, and a chimney is connected to the top of the boiler air preheater via a conveying pipe. An exhaust pipe is connected to the middle of the top of the chimney. Metal filter bags are installed inside the high-temperature bag filter dust collector to remove dust and impurities from the flue gas. An economizer is installed inside the boiler tail flue.

[0007] Preferably, the auxiliary mechanism includes a first fixing ring, a second fixing ring, a limiting rod, a fixing seat, a support seat, a filter screen, a limiting seat, a limiting plate, and a threaded pin. The first fixing ring is welded to the top of the outer wall of the exhaust pipe, and the second fixing ring is welded to the bottom of the outer wall of the exhaust pipe. Both the first fixing ring and the second fixing ring are "O" shaped structures.

[0008] Preferably, both the first and second fixing rings are internally connected to limiting rods, and the top of the outer wall of the limiting rod is welded with a fixing seat. The limiting rod can be inserted into the limiting fixing seat inside the first and second fixing rings. The limiting rods are distributed in a "+" shape, and the fixing seat has an "O" shaped structure.

[0009] Preferably, a support base is welded to the bottom of the outer wall of the fixed base. The support base has an "L" shaped cross-section and a filter screen is connected to the bottom of the support base. The support base can support the filter screen, and the filter screen can filter dust in the flue gas again.

[0010] Preferably, a limiting seat is connected to the top of the outer wall of the fixed seat, and a limiting plate is welded to the inner wall of the limiting seat. The limiting seat is arc-shaped, and the bottom end of the limiting seat is in contact with the filter screen to limit the filter screen.

[0011] Preferably, the limiting seat has a threaded pin internally connected to it, and the fixing seat has a threaded hole corresponding to the threaded pin, and the threaded pin is distributed in a "+" shape.

[0012] Preferably, the limiting seat has an "O" shaped structure and the fixing seat has an "O" shaped structure.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: When using this new biomass boiler dust removal and denitrification system, by setting the high-temperature filter bag dust collector before the traditional denitrification process, the dust can be removed first, thus solving the problem of alkali metal components in the dust poisoning the denitrification catalyst. It also eliminates the need for the original post-denitrification process to reheat the flue gas to meet the denitrification temperature problem, thereby eliminating the need for additional flue gas heating, saving operating costs. Furthermore, the auxiliary mechanism further filters the flue gas, preventing residual impurities in the flue gas from being discharged into the air, improving the flue gas treatment quality. Therefore, when using the biomass boiler dust removal and denitrification system, it plays a role in preventing denitrification catalyst poisoning and improving flue gas treatment quality. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0015] Figure 2 This is a three-dimensional structural diagram of the high-temperature filter bag dust collector of this utility model;

[0016] Figure 3 This is a schematic diagram of the three-dimensional structure of the chimney of this utility model;

[0017] Figure 4 This is a three-dimensional structural diagram of the auxiliary mechanism of this utility model;

[0018] Figure 5 This is a three-dimensional sectional view of the exhaust pipe structure of this utility model;

[0019] Figure 6 This is a three-dimensional sectional view of the support base of this utility model;

[0020] Figure 7 This is a schematic diagram of the three-dimensional structure of the filter screen of this utility model;

[0021] Figure 8 This is a three-dimensional structural diagram of the limiting rod of this utility model.

[0022] In the diagram: 1. Biomass boiler body; 2. Boiler tail flue; 3. High-temperature filter bag dust collector; 4. SCR denitrification reactor; 5. Ammonia injection device; 6. Boiler air preheater; 7. Inlet pipe; 8. Chimney; 9. Exhaust pipe; 10. Auxiliary mechanism; 1001. First fixing ring; 1002. Second fixing ring; 1003. Limiting rod; 1004. Fixing seat; 1005. Support seat; 1006. Filter screen; 1007. Limiting seat; 1008. Limiting plate; 1009. Threaded pin. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] Please see Figures 1-8This utility model provides a technical solution: a novel biomass boiler dust removal and denitrification system, including a biomass boiler body 1, a boiler tail flue 2, an SCR denitrification reactor 4, and auxiliary mechanisms 10. The boiler tail flue 2 is connected to one side of the outer wall of the biomass boiler body 1, and a high-temperature filter bag dust collector 3 is connected to the boiler tail flue 2 via a flue gas pipe. The high-temperature filter bag dust collector 3 is connected to the SCR denitrification reactor 4 via the flue. An ammonia injection device 5 is installed on the outer wall of the flue. The SCR denitrification reactor 4 is connected to a boiler air preheater 6 via a transmission pipe, and an air inlet pipe 7 is connected to one side of the bottom of the boiler air preheater 6. The boiler air preheater 6 is connected to the biomass boiler body 1 via a return gas pipe, and the top of the boiler air preheater 6 is connected to... The conveying pipeline is connected to the chimney 8, and the top and middle of the chimney 8 are connected to the exhaust pipe 9. The high-temperature filter bag dust collector 3 is equipped with metal filter bags to remove dust and impurities from the flue gas. The boiler tail flue 2 is equipped with an economizer. The auxiliary mechanism 10 includes a first fixing ring 1001, a second fixing ring 1002, a limiting rod 1003, a fixing seat 1004, a support seat 1005, a filter screen 1006, a limiting seat 1007, a limiting plate 1008, and a threaded pin 1009. The top of the outer wall of the exhaust pipe 9 is welded with a first fixing ring 1001, and the bottom of the outer wall of the exhaust pipe 9 is welded with a second fixing ring 1002. Both the first fixing ring 1001 and the second fixing ring 1002 are "O" shaped. Both ring 1001 and the second fixed ring 1002 are internally connected to limiting rods 1003, and the top of the outer wall of the limiting rod 1003 is welded to a fixing seat 1004. The limiting rod 1003 can be inserted into the fixing seat 1004 inside the first fixed ring 1001 and the second fixed ring 1002. The limiting rods 1003 are arranged in a "+" shape, and the fixing seat 1004 has an "O" shaped structure. A support seat 1005 is welded to the bottom of the outer wall of the fixing seat 1004. The support seat 1005 has an "L" shaped cross-section, and a filter screen 1006 is connected to the bottom of the support seat 1005. The support seat 1005 can support the filter screen 1006, and the filter screen 1006 can filter dust in the flue gas again. The top of the outer wall of the fixing seat 1004 is connected to... A limiting seat 1007 is connected, and a limiting plate 1008 is welded to the inner wall of the limiting seat 1007. The limiting seat 1007 is arc-shaped, and the bottom end of the limiting seat 1007 fits against the filter screen 1006 to limit the filter screen 1006. A threaded pin 1009 is threadedly connected inside the limiting seat 1007. A threaded hole corresponding to the threaded pin 1009 is opened inside the fixing seat 1004, and the threaded pin 1009 is distributed in a "+" shape. The limiting seat 1007 has an "O" shaped structure, and the fixing seat 1004 has an "O" shaped structure. The first fixing ring 1001 and the second fixing ring 1002 are parallel to each other, and the first fixing ring 1001 and the second fixing ring 1002 have fixing holes corresponding to the limiting rod 1003 inside.

[0025] For specific implementation, please refer to Figures 1-3During the operation of this biomass boiler dust removal and denitrification system, the main body of the biomass boiler 1 burns raw materials such as straw, rice husks, cotton stalks, branches, bark, wood, and sawdust. The flue gas then passes through the economizer as it reaches the boiler tail flue 2. After that, the flue gas is drawn out from the economizer and enters the high-temperature filter bag dust collector 3. At this time, the flue gas temperature is between 300-400℃. After the filter bags in the high-temperature filter bag dust collector 3 remove dust and impurities from the flue gas, it enters the SCR denitrification reactor 4. During this process, ammonia is injected through the ammonia injection device 5, so that the ammonia reducing agent enters the SCR denitrification reactor 4 together. Then, under the action of the denitrification catalyst, NOx is converted into N2 and water, completing the removal of NOx. This is better than first removing a large amount of dust and impurities through the dust collector, and the SCR system can operate normally. After the dust removal and denitrification, the flue gas returns to the boiler air preheater 6 and is finally discharged through the exhaust pipe 9 at the top of the chimney 8. During this process, ambient temperature air is stably transported to the boiler air preheater 6 through the air inlet pipe 7 for heat exchange.

[0026] This reduces the impact of alkaline components in the dust on the catalyst, solves the problems in the catalyst, and eliminates the need for the original post-denitrification process to reheat the flue gas to meet the denitrification temperature problem. Thus, it not only solves the problem of dust poisoning the catalyst, but also eliminates the need for additional flue gas heating, saving operating costs.

[0027] See Figures 3-8 During the process of flue gas being discharged through the exhaust pipe 9 at the top of the chimney 8 after treatment, the fixed seat 1004 is moved in advance so that the limiting rod 1003 is inserted into the first fixed ring 1001 and the second fixed ring 1002, thereby limiting the fixed seat 1004 to prevent it from rotating at will, and at this time the support seat 1005 forms a support point.

[0028] See Figures 5-6 Next, the filter screen 1006 is placed at the bottom of the support base 1005. At this time, the support base 1005 is located inside the exhaust pipe 9. The flue gas must pass through the filter screen 1006 before it can be discharged from the exhaust pipe 9. At this time, the flue gas is filtered again by the filter screen 1006 to prevent residual impurities in the flue gas from being discharged into the air together, thereby improving the flue gas treatment quality.

[0029] See Figures 5-8 Next, the bottom of the limiting seat 1007 is attached to the top of the fixed seat 1004. At this time, the middle part of the limiting plate 1008 is attached to the inner wall of the support seat 1005, and the bottom is in contact with the filter screen 1006. Then, the threaded pin 1009 is rotated to pass through the limiting seat 1007 and connect with the fixed seat 1004, thereby fixing the limiting seat 1007 to prevent it from moving. At this time, the limiting seat 1007 limits the filter screen 1006 to prevent it from moving and affecting the filtration of flue gas.

[0030] Furthermore, the filter screen 1006 can be removed for cleaning simply by moving the fixing base 1004 upwards, preventing it from being clogged by flue gas impurities and affecting the filtration efficiency.

[0031] In summary, when this novel biomass boiler dust removal and denitrification system is in use, the flue gas generated from the combustion of raw materials in the biomass boiler body 1 enters the high-temperature filter bag dust collector 3 through the boiler tail flue 2. After the dust and impurities in the flue gas are removed by the filter bags, it enters the SCR denitrification reactor 4. During this process, the ammonia reducing agent also enters the SCR denitrification reactor 4. Then, under the action of the denitrification catalyst, NOx is converted into N2 and water, completing the removal of NOx. This is superior to first removing a large amount of dust and impurities through a dust collector, and the SCR system can operate normally. Afterwards, it is discharged through the chimney 8. By setting the high-temperature filter bag dust collector 3 before the traditional denitrification process, the problem of dust poisoning of the catalyst is solved. At the same time, no additional flue gas heating is required, saving operating costs. Furthermore, the auxiliary mechanism 10 further filters the flue gas to prevent residual impurities in the flue gas from being discharged into the air, thereby improving the quality of flue gas treatment. The contents not described in detail in this description belong to the prior art known to those skilled in the art.

[0032] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A novel biomass boiler dust removal and denitrification system, comprising a biomass boiler body (1), a boiler tail flue (2), an SCR denitrification reactor (4), and auxiliary mechanisms (10), wherein the outer wall of the biomass boiler body (1) is connected to the boiler tail flue (2), and the boiler tail flue (2) is connected to a high-temperature filter bag dust collector (3) through a flue gas pipe, and the high-temperature filter bag dust collector (3) is connected to the SCR denitrification reactor (4) through the flue, characterized in that: The outer wall of the flue is equipped with an ammonia injection device (5). The SCR denitrification reactor (4) is connected to the boiler air preheater (6) through a transmission pipeline. The bottom side of the boiler air preheater (6) is connected to an air inlet pipe (7). The boiler air preheater (6) is connected to the biomass boiler body (1) through a return gas pipe. The top of the boiler air preheater (6) is connected to a chimney (8) through a conveying pipeline. The top middle of the chimney (8) is connected to an exhaust pipe (9). The high-temperature filter bag dust collector (3) is equipped with metal filter bags to remove dust impurities in the flue gas. The tail flue (2) of the boiler is equipped with an economizer.

2. The novel biomass boiler dust removal and denitrification system according to claim 1, characterized in that: The auxiliary mechanism (10) includes a first fixing ring (1001), a second fixing ring (1002), a limiting rod (1003), a fixing seat (1004), a support seat (1005), a filter screen (1006), a limiting seat (1007), a limiting plate (1008), and a threaded pin (1009). The first fixing ring (1001) is welded to the top of the outer wall of the exhaust pipe (9), and the second fixing ring (1002) is welded to the bottom of the outer wall of the exhaust pipe (9). Both the first fixing ring (1001) and the second fixing ring (1002) are "O" shaped structures.

3. The novel biomass boiler dust removal and denitrification system according to claim 2, characterized in that: The first fixing ring (1001) and the second fixing ring (1002) are both connected to the limiting rod (1003), and the top of the outer wall of the limiting rod (1003) is welded with a fixing seat (1004). The limiting rod (1003) can be inserted into the limiting fixing seat (1004) inside the first fixing ring (1001) and the second fixing ring (1002). The limiting rod (1003) is distributed in a "+" shape, and the fixing seat (1004) has an "O" shape structure.

4. The novel biomass boiler dust removal and denitrification system according to claim 3, characterized in that: The bottom of the outer wall of the fixed seat (1004) is welded with a support seat (1005). The support seat (1005) has an "L" shaped cross section and a filter screen (1006) is connected to the bottom of the support seat (1005). The support seat (1005) can support the filter screen (1006), and the filter screen (1006) can filter the dust in the flue gas again.

5. The novel biomass boiler dust removal and denitrification system according to claim 4, characterized in that: The top of the outer wall of the fixed seat (1004) is connected to the limiting seat (1007), and the inner wall of the limiting seat (1007) is welded with a limiting plate (1008). The limiting seat (1007) is arc-shaped, and the bottom end of the limiting seat (1007) is attached to the filter screen (1006) to limit the filter screen (1006).

6. The novel biomass boiler dust removal and denitrification system according to claim 5, characterized in that: The limiting seat (1007) is internally threaded with a threaded pin (1009), and the fixing seat (1004) has a threaded hole corresponding to the threaded pin (1009) inside, and the threaded pin (1009) is distributed in a "+" shape.

7. The novel biomass boiler dust removal and denitrification system according to claim 5, characterized in that: The limiting seat (1007) has an "O" shaped structure, and the fixing seat (1004) has an "O" shaped structure.

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