Positive pressure conveying type boiler blending combustion system

Abstract

The utility model discloses a positive pressure conveying type boiler blending combustion system which comprises an injection pipe, the outside of the injection pipe is respectively connected with a first hopper, a first feeding air pipe and a conveying pipe, the outside of the first hopper is connected with a conveying auger, the outside of the first feeding air pipe is connected with a feeding fan, and the outside of the first feeding air pipe is connected with a discharging pipe. A first valve fixedly connected to the bottom of the injection pipe is arranged under the first hopper, the lower end of the first valve is connected with a smashing mechanism through a transfer material pipe, the bottom of the smashing mechanism is connected with a material returning pipe, one end of the material returning pipe is connected with a material returning fan, and the other end of the material returning pipe is connected with the first hopper or a material conveying auger. The transfer material pipe comprises a second hopper arranged on the top of the smashing mechanism, and the upper end of the second hopper is connected with a first valve through a net pipe. According to the utility model, caked biomass fuel can be crushed and returned, so that the problems of accumulation and plugging of the biomass fuel are avoided.

Description

Technical Field

[0001] This utility model relates to a boiler co-firing mechanism, and more particularly to a positive pressure conveying boiler co-firing system. Background Technology

[0002] To improve the combustion efficiency and reduce carbon emissions of coal-fired boilers, manufacturers currently use boiler co-firing mechanisms to add a certain amount of biomass fuel to the boiler. This allows the biomass fuel, when mixed with different types of coal, to achieve performance indicators that meet the boiler's design requirements. Based on this, the boiler co-firing mechanism currently used by manufacturers, as shown in patent 202123338853.0, mainly consists of an injection pipe, a hopper, a feeding duct, and a feeding fan. During operation, a conveying auger vertically drops the pulverized biomass fuel into the injection pipe through the hopper. Simultaneously, the feeding fan applies horizontal airflow towards the injection pipe, causing the biomass fuel to enter the injection pipe and then be blown into the boiler along the feeding duct, thus achieving the quantitative delivery of biomass fuel.

[0003] However, the drawback of this structure in practical use is that, limited by the efficiency of biomass fuel delivery, it requires pre-crushing the biomass fuel in a crushing device before placing it in a storage tank, and then quantitatively adding it into the injection pipe according to demand. On-site crushing of the biomass fuel is not possible. This leads to a small amount of clumping in the pre-crushed biomass fuel during storage and compression transportation. Consequently, these fuel lumps cannot move upwards along the feeding duct into the boiler under the influence of airflow after entering the injection pipe or feeding duct. This causes two problems: firstly, the fuel lumps block the inlet; secondly, the amount of biomass fuel added each time is not the set amount, thus reducing its co-firing effect.

[0004] Therefore, existing boiler co-firing mechanisms need to address the problem of biomass fuel agglomeration. Utility Model Content

[0005] The purpose of this invention is to provide a positive pressure conveying boiler co-firing system. It can crush and recycle agglomerated biomass fuel, thereby avoiding the problems of biomass fuel accumulation and blockage.

[0006] The technical solution of this utility model is as follows: a positive pressure conveying boiler co-firing system, including an injection pipe, to which a first hopper, a first feeding air pipe and a conveying pipe are respectively connected. A conveying auger is connected to the outside of the first hopper, and a feeding fan is connected to the outside of the first feeding air pipe. A first valve is fixedly connected to the bottom of the injection pipe directly below the first hopper. The lower end of the first valve is connected to a crushing mechanism via a transfer pipe. A return pipe is connected to the bottom of the crushing mechanism. One end of the return pipe is connected to a return fan, and the other end is connected to the first hopper or the conveying auger. The transfer pipe includes a second hopper located at the top of the crushing mechanism, and the upper end of the second hopper is connected to the first valve via a mesh pipe.

[0007] In the aforementioned positive pressure conveying boiler co-firing system, the conveying pipe forms an upward inclined bend at one end near the injection pipe, and the end of the first valve is flush with the lower end of the bend.

[0008] In the aforementioned positive pressure conveying boiler co-firing system, the middle part of the conveying pipe forms an upward inclined bend, and a second valve is connected to the conveying pipe at the bottom of the bend. The lower end of the second valve is connected to the second hopper via a discharge pipe.

[0009] In the aforementioned positive pressure conveying boiler co-firing system, one end of the discharge pipe is connected to a second feeding air pipe, and the end of the second feeding air pipe is connected to a return air fan.

[0010] In the aforementioned positive pressure conveying boiler co-firing system, electric valves are installed on both the second feeding air pipe and the return pipe.

[0011] In the aforementioned positive pressure conveying boiler co-firing system, a first observation plate made of transparent material is connected to the injection pipe on one side of the first valve.

[0012] In the aforementioned positive pressure conveying boiler co-firing system, the second hopper and the crushing mechanism are separated from each other. The outside of the second hopper is connected to a mounting bracket via a weighing sensor, and the lower end of the second hopper is connected to a third valve.

[0013] Compared with the prior art, this utility model has the following characteristics:

[0014] (1) Through the cooperation of the first valve, the crushing mechanism, the return pipe and the return fan, the biomass fuel can be fed into the crushing mechanism by the first valve after it clumps and falls to the bottom of the injection pipe. After being crushed, the biomass fuel is blown back into the first hopper or the conveying auger by the return fan, thereby realizing the re-crushing of the fuel clumps and effectively preventing the accumulation and blockage of fuel clumps in the injection pipe. On this basis, by limiting the structure of the transfer pipe, it is possible to effectively prevent the return fan from causing the fuel clumps in the second hopper and the mesh pipe to move in the opposite direction during the blowing, thereby ensuring the stability of the falling fuel clumps.

[0015] (2) By limiting the structure of the bend in the conveying pipe, it is possible to screen biomass fuel. That is, the completely crushed biomass fuel can be directly conveyed upward along the inclined bend and enter the boiler, while the fuel lumps that are not completely crushed will fall back into the crushing mechanism along the side wall of the bend, thereby improving the screening and crushing effect of biomass fuel and preventing the accumulation and blockage of small pieces of biomass fuel during the conveying process.

[0016] (3) By setting the first observation plate, the operator can observe the fuel accumulation in the injection pipe in real time during operation and flexibly judge whether the accumulated material needs to be crushed according to the amount of material, thereby improving the operator's operational convenience; by cooperating with the second hopper and the weighing sensor, the first hopper can be opened after the conveying action of this utility model to let the fuel block fall into the second hopper, and then the fallen fuel block is weighed and it is determined whether the fuel block needs to be crushed and sent back into the first hopper or the conveying auger, thereby eliminating the manual operation process and improving the use effect of this utility model;

[0017] Therefore, this invention can crush and recycle agglomerated biomass fuel, thereby avoiding the problems of biomass fuel accumulation and blockage. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of Example 1;

[0019] Figure 2 This is a structural schematic diagram of Example 2;

[0020] Figure 3 This is a schematic diagram of the structure of Example 3.

[0021] The labels in the attached diagram are as follows: 1-spray pipe, 2-first hopper, 3-feeding air duct, 4-conveying pipe, 5-feeding auger, 6-feeding fan, 7-first valve, 8-crushing mechanism, 9-return pipe, 10-return fan, 11-second hopper, 12-mesh pipe, 13-second valve, 14-drop pipe, 15-second feeding air duct, 16-first observation plate, 17-second observation plate, 18-mounting bracket, 19-third valve, 401-bend. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0023] Example 1. Positive pressure conveying boiler co-firing system, configured as follows: Figure 1As shown, the device includes a spray pipe 1, to which a first hopper 2, a first feeding air pipe 3, and a conveying pipe 4 are connected respectively. A conveying auger 5 is connected to the outside of the first hopper 2, and a feeding blower 6 is connected to the outside of the first feeding air pipe 3. A first valve 7 is fixedly connected to the bottom of the spray pipe 1 directly below the first hopper 2. The first valve 7 can be a rectangular discharge valve or a rectangular multi-leaf flap valve. The lower end of the first valve 7 is connected to a crushing mechanism 8 via a transfer pipe. The crushing mechanism 8 is a conventional crushing device used for biomass fuel. A return pipe 9 is connected to the bottom of the crushing mechanism 8. One end of the return pipe 9 is connected to a return blower 10, and the other end of the return pipe 9 is connected to the first hopper 2. The transfer pipe includes a second hopper 11 set at the top of the crushing mechanism 8. The upper end of the second hopper 11 is connected to the first valve 7 via a mesh pipe 12.

[0024] The conveying pipe 4 has an upwardly inclined bend 401 at one end near the spray pipe 1, and the end of the first valve 7 is flush with the lower end of the bend 401.

[0025] A transparent first observation plate 16 is detachably connected to the injection pipe 1 on one side of the first valve 7. The first observation plate 16 is sealed around its perimeter by gaskets.

[0026] In this embodiment, the screed biomass fuel is fed into the first hopper 2 by the conveying auger 5, and then falls vertically into the injection pipe 1 along the first hopper 2. After the biomass fuel falls into the injection pipe 1, the feeding fan 6 and the feeding duct 3 work together to apply horizontal conveying air force, causing the powdered biomass fuel to be blown directly into the boiler along the conveying pipe 4, while the incompletely pulverized or lumpy biomass fuel will fall directly or be intercepted by the bending part 401 and fall onto the first hopper 2 below. After the biomass fuel is blown, the operator can observe the accumulation of material in the injection pipe 1 through the first observation plate 16, and determine whether the accumulated material needs to be pulverized and re-blown based on the amount of material. If the amount of material accumulated on the first hopper 2 is relatively small, no processing is required; if the amount of material accumulated on the first hopper 2 is relatively large, the first hopper 2 is opened first to allow the accumulated material to fall into the crushing mechanism 8 below, then the first hopper 2 is closed and the crushing mechanism 8 and the return fan 10 are turned on, so that the crushing mechanism 8 crushes it and then sends it back into the spray pipe 1 through the cooperation of the return fan 10, the return pipe 9 and the first hopper 2, thereby realizing the crushing and re-blowing of the accumulated material.

[0027] With the above-mentioned combination, this embodiment can prevent the blockage problem caused by material accumulation on the one hand, and ensure that the amount of biomass fuel fed into the boiler each time meets the requirements on the other hand, effectively solving the problem of reduced biomass fuel entering the boiler due to agglomeration.

[0028] Example 2. Positive pressure conveying boiler co-firing system, configured as follows: Figure 2 As shown, the device includes a spray pipe 1, to which a first hopper 2, a first feeding air pipe 3, and a conveying pipe 4 are connected respectively. A conveying auger 5 is connected to the outside of the first hopper 2, and a feeding blower 6 is connected to the outside of the first feeding air pipe 3. A first valve 7 is fixedly connected to the bottom of the spray pipe 1 directly below the first hopper 2. The first valve 7 can be a rectangular discharge valve or a rectangular multi-leaf flap valve. The lower end of the first valve 7 is connected to a crushing mechanism 8 via a transfer pipe. The crushing mechanism 8 is a conventional crushing device used for biomass fuel. A return pipe 9 is connected to the bottom of the crushing mechanism 8. One end of the return pipe 9 is connected to a return blower 10, and the other end of the return pipe 9 is connected to the first hopper 2. The transfer pipe includes a second hopper 11 set at the top of the crushing mechanism 8. The upper end of the second hopper 11 is connected to the first valve 7 via a mesh pipe 12.

[0029] The middle part of the conveying pipe 4 forms an upwardly inclined bend 401. A second valve 13 is connected to the bottom of the conveying pipe 4 at the bottom of the bend 401. The second valve 13 can be an electric butterfly valve. The lower end of the second valve 13 is connected to the second hopper 11 via an downwardly inclined drop pipe 14.

[0030] One end of the discharge pipe 14 is connected to a second feeding air pipe 15, and the end of the second feeding air pipe 15 is connected to a return air fan 10.

[0031] Electric valves are installed on the second feeding air duct 15 and the return pipe 9.

[0032] A transparent first observation plate 16 is detachably connected to the injection pipe 1 on one side of the first valve 7. The first observation plate 16 and the second observation plate 17 are sealed around their perimeter by gaskets.

[0033] Compared with Embodiment 1, this embodiment is applicable to a boiler co-firing system in which a bend 401 is formed in the middle of the conveying pipe 4. When the material accumulates at the bottom of the bend 401, the operator can first open the second valve 13 and the return fan 10, so that the material is blown by the return fan 10 and enters the second hopper 11 along the second feeding pipe 15; then the material is crushed and re-conveyed by the crushing mechanism 8 in the same way, so as to realize the return function of the boiler co-firing mechanism.

[0034] Example 3. Positive pressure conveying boiler co-firing system, configured as follows: Figure 3As shown, the device includes a spray pipe 1, to which a first hopper 2, a first feeding air pipe 3, and a conveying pipe 4 are connected respectively. A conveying auger 5 is connected to the outside of the first hopper 2, and a feeding blower 6 is connected to the outside of the first feeding air pipe 3. A first valve 7, fixedly connected to the bottom of the spray pipe 1, is located directly below the first hopper 2. This first valve 7 can be a rectangular discharge valve or a rectangular multi-leaf flap valve. The lower end of the first valve 7 is connected to a crushing mechanism 8 via a transfer pipe. This crushing mechanism 8 is a conventional crushing device used for biomass fuel. A return pipe 9 is connected to the bottom of the crushing mechanism 8. One end of the return pipe 9 is connected to a return blower 10, and the other end is connected to the conveying auger 5. The transfer pipe includes a second hopper 11 located at the top of the crushing mechanism 8. The upper end of the second hopper 11 is connected to the first valve 7 via a mesh pipe 12.

[0035] The conveying pipe 4 has an upwardly inclined bend 401 at one end near the spray pipe 1, and the end of the first valve 7 is flush with the lower end of the bend 401.

[0036] The second hopper 11 and the crushing mechanism 8 are separated from each other. The outside of the second hopper 11 is connected to a mounting bracket 18 via a weighing sensor, and the lower end of the second hopper 11 is connected to a third valve 19.

[0037] Compared to Example 1, in this example, after the biomass fuel blowing is completed, the first hopper 2 is opened, causing the accumulated material to fall into the second hopper 11. Then, the first hopper 2 is closed, and the accumulated material is weighed using a weighing sensor. Based on the weight of the accumulated material, it is determined whether it needs to be crushed and returned. If the weight of the accumulated material is less than a set threshold, the first hopper 2 is closed, and the next feeding operation proceeds normally. If the weight of the accumulated material is greater than the set threshold, the second hopper 11 is opened, and the accumulated material is crushed and returned in the same manner.

[0038] Based on the above, to improve the conveying efficiency of biomass fuel, after the accumulated material is weighed, the conveying auger 5 can first send the corresponding biomass fuel into the injection pipe 1 according to the weight of the accumulated material, and then the feeding blower 6 will send the biomass fuel into the boiler. Then the boiler co-firing system completes the feeding action, and the crushing mechanism 8 crushes the accumulated material and sends it back to the conveying auger 5. That is, the conveying auger 5 replaces the conveying of an equal amount of biomass fuel, thereby saving the time of crushing and returning the accumulated material and improving the overall feeding efficiency.

Claims

1. A positive pressure conveying boiler blending system, comprising a jet pipe (1), the outer part of the jet pipe (1) is respectively connected with a first hopper (2), a first feeding air pipe (3) and a feeding pipe (4), the outer part of the first hopper (2) is connected with a feeding auger (5), the outer part of the first feeding air pipe (3) is connected with a feeding air fan (6), characterized in that: The first hopper (2) is provided with a first valve (7) fixedly connected to the bottom of the injection pipe (1), the lower end of the first valve (7) is connected with a crushing mechanism (8) through a transfer pipe, the bottom of the crushing mechanism (8) is connected with a return pipe (9), one end of the return pipe (9) is connected with a return fan (10), the other end of the return pipe (9) is connected with the first hopper (2) or a conveying auger (5); the transfer pipe comprises a second hopper (11) arranged at the top of the crushing mechanism (8), the upper end of the second hopper (11) is connected with the first valve (7) through a mesh pipe (12).

2. The forced draft boiler hybrid system of claim 1, wherein: The conveying pipe (4) is formed with an upwardly inclined bending portion (401) near one end of the injection pipe (1), the end of the first valve (7) is flush with the lower end of the bending portion (401).

3. The forced draft boiler hybrid system of claim 1, wherein: The middle part of the conveying pipe (4) is formed with an upwardly inclined bending portion (401), the second valve (13) is connected to the conveying pipe (4) at the bottom of the bending portion (401), the lower end of the second valve (13) is connected with the second hopper (11) through a dropping pipe (14).

4. The forced draft boiler hybrid system of claim 3, wherein: One end of the dropping pipe (14) is connected with a second conveying air pipe (15), the end of the second conveying air pipe (15) is connected with the return fan (10).

5. The forced draft boiler hybrid system of claim 4, wherein: Electric valves are arranged on the second conveying air pipe (15) and the return pipe (9).

6. The forced draft boiler hybrid system of claim 1, wherein: The injection pipe (1) on one side of the first valve (7) is connected with a first observation plate (16) made of transparent material.

7. The forced draft boiler hybrid system of claim 1, wherein: The second hopper (11) and the crushing mechanism (8) are separated from each other, the second hopper (11) is connected with a mounting bracket (18) through a weighing sensor at the outside, the lower end of the second hopper (11) is connected with a third valve (19).

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