A flow guide interface device for feeding biomass boiler

Abstract

The invention discloses a flow guide interface device for feeding a biomass boiler, comprising a material guide cylinder, a material pressure air chamber and a material broadcasting air chamber. A bottom plate flow guide structure is arranged at the bottom of the material guide cylinder, and the bottom plate flow guide structure is composed of a material guide bottom plate and a lining plate. The material guide bottom plate is located at the rear end of the material guide cylinder, and the lining plate is located at the front end of the material guide cylinder. A feeding air nozzle is formed between the lining plate and the material guide bottom plate. The material guide bottom plate is arranged to have a downwardly inclined "nose" shape structure with two sides folded downward. The material broadcasting air chamber is located at the bottom of the material guide cylinder, and the material guide bottom plate cooperates with the material broadcasting air chamber to form a material broadcasting air nozzle with a large middle portion and small two sides. The material pressure air chamber is located at the upper portion of the material guide cylinder, and the rear end of the material pressure air chamber is inclined toward the material guide cylinder to form a material pressure air nozzle. The flow guide interface device can prevent problems such as uneven feeding, wear of the feeding interface bottom plate, and poor feeding caused by stacking of materials, and effectively prevent backfire and control the fuel landing point and suspended combustion share, thereby improving the thermal efficiency of the boiler and improving environmental protection performance.

Description

Technical Field

[0001] The invention relates to the technical field of biomass boiler feeding, in particular to a flow guide interface device for biomass boiler feeding. Background Art

[0002] With the gradual improvement of environmental protection requirements and the development of boiler technology, the country has increasingly supported the use of renewable energy such as biomass; direct-fired biomass boilers that use biomass fuels such as branches, cotton stalks, crop straw, waste firewood and other renewable materials as fuel have also developed rapidly.

[0003] At present, the combustion equipment of biomass boilers is mainly divided into two categories, one is the grate type, including chain grates, reciprocating grates, water-cooled vibrating grates, etc., and the other is the fluidized bed type. Due to the particularity of the fuel itself, its volume density is small, it is generally long and has poor fluidity. Therefore, the feeding of boilers using biomass bulk as fuel adopts traditional feeding devices; currently there are mainly spiral feeding and chute feeding, but no matter which one is used, there is a problem, that is, the uniform distribution of raw materials along the width of the grate. Because these feeding methods are all borne by several set feeding ports. Due to the poor fluidity of biomass raw materials, it is not easy to distribute the raw materials evenly when they fall on the grate, and they often form several longitudinal strip-shaped raw material layers. The consequences are poor material distribution, uneven fuel distribution, local piled materials with heavy materials or large particle size, less or no materials in some parts, resulting in uneven ventilation and uneven air supply of the grate, air short circuit in some parts, insufficient air in some parts, incomplete combustion and prolonged burning time caused by piled materials, and easy occurrence of local high-temperature combustion, uneven temperature field in the furnace, NO X and SO X The initial emission concentration of pollutants increases, the environmental performance is poor, and it is easy to burn the combustion equipment, seriously affecting the combustion effect, combustion efficiency, boiler thermal efficiency, boiler environmental performance and operation cycle. For circulating fluidized bed boilers, uneven material placement affects the environmental performance indicators of the boiler.

[0004] Moreover, the feed port of the biomass fuel boiler is mostly made of refractory concrete casting. Because the surface of the feed port casting is rough and not smooth, the resistance is large, which blocks the fuel and easily causes poor feeding and accumulation at the feed port, causing flashback combustion. At the same time, the biomass fuel particles are large, irregular in shape, and rough on the surface. During the feeding process, the feed port casting is severely worn, the maintenance cost is high, and the production and operation cycle is seriously affected.

[0005] In the traditional feeding method, the fuel is mostly in the middle position near the feeding port, and the material is heavy or has a large particle size, while there is less fuel on both sides, resulting in uneven distribution of the fuel in the furnace. Even if the traditional lower broadcasting air is added, it is difficult to broadcast the fuel, and the uneven feeding is still a disadvantage that is difficult to overcome. Chinese patent application No. 201821834958.0 discloses an interface device for a biomass boiler feeder, wherein a sealed jacket is formed between a feeding cylinder and an outer cylinder, an air supply interface is provided on the outer cylinder, and a sealing pipe extending to the inside of the feeding cylinder is provided on the feeding cylinder, the air supply interface, The sealing tubes are all connected with the jacket, and the air is ejected at high speed to seal the feeding port. A feeding device is provided at one end of the feeding cylinder to eject the air in the jacket at high speed. The feeding device is a feeding hole opened at the lower front end of the jacket. Although the diffusion function of the air is utilized to improve the combustion effect, the problem is that the sealing tube is inside the feeding cylinder. While performing air sealing to prevent backfire, it does not accelerate the feeding and the feeding of the fuel with higher density. The fuel is still in direct contact with the feeding cylinder. There is no equalizing measure. The fuel is still fed by thrust, and uneven feeding will still occur. Uneven feeding cannot be avoided. The material-dispensing structure is a conventional structure. It cannot completely diffuse the fuel by relying solely on the material-dispensing holes, and uneven feeding is inevitable, resulting in uneven ventilation of the grate, which will still lead to air short circuit or air shortage problems, affecting combustion efficiency; Chinese patent application No. 201420850655.3 discloses a biomass boiler feeding device, and the guiding material-dispensing mechanism includes a rotating shaft with a hollow structure, a guide plate fixedly arranged on the rotating shaft, a material-dispensing air hole opened above the connection between the guide plate and the rotating shaft, and a handle for adjusting the rotation of the rotating shaft. One end of the rotating shaft is sealed, and the other end is connected to a wind source. In fact, relying solely on the broadcasting air holes can accelerate the feeding speed and blow the fuel into the furnace, but it cannot solve the problem of uneven fuel distribution, especially the fuel is thicker in the middle and cannot be completely dispersed, and it does not have anti-backfire function. Chinese patent application No. 201922472874.8 discloses a biomass fuel boiler feeding device that improves combustion efficiency. The discharge end of the receiving plate is provided with a bulk feeder for connecting to the boiler. The bulk feeder includes a bottom plate and more than three partitions. A bulk feed channel is formed between two adjacent partitions and the bottom plate. The width of the bulk feed channel gradually increases along the direction of fuel flow. A rotating shaft driven by a motor is provided on the receiving plate, and a turning blade is provided on the rotating shaft. The turning blades on the two adjacent rotating shafts are staggered.This structure can make the fuel be turned over more fully, reducing the dead corners that the turning blades cannot reach. First of all, not to mention its high manufacturing cost, the motor and its moving parts are prone to failure and difficult to repair. In addition, due to the high temperature of the discharge port, motor heat dissipation is also a big problem. Due to the characteristics of biomass, it is relatively soft and tough. Relying on the form of blades to shift the material, it is easy for the blades to be entangled and blocked, causing the blades to be stuck, which can easily cause the motor and its moving parts to fail and be difficult to repair. In addition, the fuel cannot be fully dispersed, which is obviously not practical. In addition, due to the expansion of the feed port, it is more prone to problems such as backfire and feed port wear.

[0006] Chinese patent application No. 201610748962.4 discloses a method and device for preventing blockage of a biomass boiler screw feeder. In front of the biomass boiler screw feeder is a plug pipe. The biomass boiler screw feeder enters the feed trough through the plug pipe. The backfire of the feed trough is prevented by the plug in the plug pipe; the plug in the plug pipe is prevented by shortening the length of the plug pipe, and a backfire prevention baffle is installed in the plug pipe. The device mainly solves the function of plug blockage and backfire prevention, but cannot play the role of equalizing the material, and cannot solve the problems of uneven feeding and wear of the bottom plate of the feeding interface. Similarly, Chinese patent application No. 201420086172.0 discloses a radially adjustable plug device for a biomass fuel screw feeder, including a feeder housing with a built-in feeder screw. The cross-sectional size of the plug channel can be conveniently adjusted radially by the relative rotation of the bent plug plate on the transition interface. Although it can prevent the leakage of high-temperature gas in the furnace and reduce the risk of clogging of the feeding equipment, it cannot solve the above problems.

[0007] Chinese patent application No. 201020247310.0 discloses a biomass fuel boiler feed port with a stainless steel plate, on which a tubular feed port with an outer metal plate layer and a refractory concrete layer in the middle is connected, and on the bottom wall surface of the refractory concrete layer of the feed port, a wear-resistant layer made of a 6-10mm thick heat-resistant stainless steel plate is fixed by bolts or bonding, and the length of the wear-resistant layer made of the stainless steel plate extends 5-15mm beyond the furnace inner wall. Although the wear problem of the biomass fuel on the feed port is solved, the stainless steel plate extends out of the furnace inner wall, and the feed port is easily deformed and hanged materials are accumulated due to the high temperature in the furnace, resulting in poor feeding, and the stainless steel plate is fixed by bolts, which causes convex or concave points on the inner side of the stainless steel plate, which is easily blocked by hanged materials, thereby causing feeding difficulties, and the bonding fixation is easily fatigued and fails to fall off due to the influence of high temperature, causing the stainless steel plate to loosen and be not firmly fixed, and the problems of uneven feeding and stacking cannot be solved.

[0008] Chinese patent application No. 200820035506.6 discloses a flashback prevention device for a biomass straw boiler feed inlet, comprising air ducts arranged in a row, wherein the outlets of the air ducts face the biomass straw boiler feed inlet, and the inlet of the air ducts is connected to the secondary air duct of the boiler furnace through a suction device. The characteristic that the high-pressure hot air is higher than the positive pressure generated by the pulsation of the furnace flue gas is utilized to prevent the flashback from being ejected out of the furnace, which is beneficial to the safe operation of the boiler. The high-pressure hot air can also spread the straw and supplement the oxygen, which is beneficial to the full combustion of the straw. Since the feed inlet is sealed with high-pressure hot air, the air volume of the induced draft fan can be reduced during the operation of the boiler, the heat loss can be reduced, and the thermal efficiency can be improved. However, the uneven distribution of the fuel cannot be solved, and the incomplete combustion caused by the stacking of materials is easy to cause local high-temperature combustion, which will not reduce NO X and SO X The amount produced is not environmentally friendly. The same problem also exists in Chinese patent application No. 201810407051.4.

[0009] The existing main forms include spiral feeding, chute feeding or hydraulic pushing, such as patent publication numbers CN104566434A, CN205619355U, CN202792079U, CN115451401A, all of which have problems such as uneven feeding, wear of the feeding interface bottom plate, tempering, stacking problems or wear and tear of moving parts, which affect the combustion effect, combustion efficiency, environmental protection performance and long-term operation of the boiler, and this problem has not been perfectly solved until now. In view of the problems existing in the above-mentioned split body, a flow guide interface device for biomass boiler feeding is proposed. Summary of the invention

[0010] The technical problem to be solved by the present invention is to overcome the existing defects and provide a flow guide interface device for biomass boiler feeding, which can prevent problems such as uneven feeding, wear of the feeding interface bottom plate and material piling, and effectively prevent backfire and control the fuel landing point and suspended combustion share, improve the combustion effect, improve the combustion efficiency and boiler thermal efficiency, reduce the initial emission concentration of pollutants and greatly improve the environmental protection performance, which is conducive to the long-term safe and stable operation of the boiler and can effectively solve the problems in the background technology.

[0011] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a flow guide interface device for feeding a biomass boiler, comprising a material guide cylinder, a material pressing air chamber and a material broadcasting air chamber, a bottom plate flow guide structure is arranged at the bottom of the material guide cylinder, the bottom plate flow guide structure is composed of a material guide bottom plate and a lining plate, the material guide bottom plate is located at the rear end of the material guide cylinder, the lining plate is located at the front end of the material guide cylinder, the material guide bottom plate is arranged to be a downwardly inclined "nose" shaped structure with two sides folded downward, the inclination angle is set to α, and the nose height of the terminal end of the material guide bottom plate feeding port is set to H, and it extends obliquely downward toward the furnace, the material broadcasting air chamber is located at the bottom of the material guide cylinder, and the material broadcasting air chamber is arranged at the bottom of the material guide cylinder. The rear end is inclined toward the material guide cylinder, and the material guide bottom plate cooperates with the material broadcasting air chamber to form a material broadcasting air nozzle which is larger in the middle and smaller on both sides. A material guide interface is provided at the front end of the material guide cylinder, and a lining plate is arranged between the front end of the material guide bottom plate and the material guide interface. The width of the lining plate is consistent with the width of the material guide bottom plate, and the lining plate is inclined toward the nose-shaped starting point direction of the material guide bottom plate to form a material feeding air nozzle which is higher in the front and lower in the back, and the lining plate covers the front end of the material guide bottom plate, and a material pressing air chamber is arranged on the upper part of the material guide cylinder, and the rear end of the material pressing air chamber is inclined toward the material guide cylinder, and the material pressing air chamber and the material guide cylinder cooperate to form a material pressing air nozzle which is higher in the front and lower in the back.

[0012] Furthermore, the lining plate is connected with the material broadcasting air chamber to form a feeding air chamber with a feeding air nozzle. The connecting air opening between the feeding air chamber and the material broadcasting air chamber is located at the front end of the lining plate and away from the feeding air nozzle. The feeding air nozzle is connected to the lining plate and the material guide bottom plate through reinforcing ribs.

[0013] Furthermore, a broadcasting air interface is provided at the bottom of the broadcasting air chamber, and the feeding air of the feeding air chamber is drawn from the broadcasting air chamber or an independent feeding air introduction is provided.

[0014] Furthermore, the middle width of the broadcasting air nozzle is set to the nose width B, the width of the broadcasting air nozzle is set to A, and the ratio of the nose width B to the broadcasting air nozzle width A, that is, B / A = 0.1-0.3.

[0015] Furthermore, the nose height H=0.1-0.3 meters.

[0016] Furthermore, the inclination angle α=0-15°.

[0017] Furthermore, the shell of the material guide cylinder is made of heat-resistant and wear-resistant stainless steel material, and the rear end of the material guide cylinder extends to the furnace, the rear end of the material guide cylinder is flush with the edge of the castable on the inside of the furnace, and the outer side of the material guide cylinder is fixed by welding with heat-resistant metal rivets in the castable or on the heating surface.

[0018] Furthermore, the rear end of the pressing air chamber is inclined toward the material guide cylinder, and together with the top plate of the material guide cylinder, forms a pressing air nozzle with a high front and a low rear, and a pressing air interface is provided on the pressing air chamber.

[0019] Furthermore, the nozzles of the material broadcasting air chamber and the material pressing air chamber are respectively connected to the material guiding cylinder through reinforcing ribs.

[0020] Furthermore, the entire material guiding cylinder can be tilted downward, and the angle is set to β, β=0-60°.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The flow guide interface device of the present invention adopts a flow guide structure of a "nose"-shaped material guide bottom plate, so that the fuel is gradually and naturally diverted to both sides along the material guide bottom plate when entering the material guide cylinder. In addition, the downward-inclined "nose"-shaped material guide structure with a high middle and low sides makes it easier for the fuel to be diverted to both sides, thereby solving the problem of more fuel in the middle position near the feed port and less fuel on both sides in the traditional feeding method, which causes uneven distribution of fuel in the furnace and is difficult to spread even if the traditional lower spreading wind is added.

[0023] 2. The "nose"-shaped upturned material broadcasting air nozzle structure of the present invention makes the air volume in the middle slightly larger and the air volume on both sides slightly smaller, which is more conducive to material distribution and broadcasting on both sides, so that the feed can be evenly broadcast and evenly scattered on the combustion equipment, which is beneficial to improving the combustion effect and improving the boiler combustion efficiency and boiler thermal efficiency. The "nose"-shaped structure of the material guide bottom plate, which is high in the middle and low on both sides and the width of the two sides gradually narrows, is the same as the natural falling trend of the fuel, and is also more conducive to the falling of the fuel. It is not easy for the fuel to stagnate and pile up, and it is also more conducive to the fuel broadcasting and evenly broadcasting on both sides, and the material distribution effect is better.

[0024] 3. The material guide cylinder adopts a lining plate and a "nose"-shaped material guide bottom plate structure, and the lining plate covers the "nose"-shaped structure to a certain extent, and at the same time forms a downward-inclined feeding air nozzle at the end of the lining plate; under the action of the downward-inclined high-speed feeding air, the feeding air is pressed toward the "nose"-shaped material guide bottom plate, on the one hand, an air cushion is formed on the material guide bottom plate, which is beneficial to the flow and uniformity of the fuel, and on the other hand, the feed is smoothly delivered into the furnace for combustion under the transportation of the downward-inclined high-speed feeding air of the feeding air nozzle, preventing blockage, and adjusting the material drop point and suspended combustion share in the furnace through the nozzle wind speed, while also enhancing the positive pressure sealing and anti-flashback function of the feeding air.

[0025] 4. In the biomass boiler adopting the flow guide interface device of the present invention, the material-broadening air nozzle and the material-pressing air nozzle respectively form high-speed air jets with the effects of upward supporting and downward pressing of the material, which effectively prevent the fuel from backfired at the material inlet. Under the action of the "nose"-shaped material-broadening bottom plate of the material-broadening cylinder and the upward-curved "nose"-shaped material-broadening air nozzle, the material is evenly spread, the landing position of the biomass fuel and the uniform material-broadening effect are effectively adjusted, and the combustion conditions and suspended combustion ratio of biomass fuel with lighter weight or finer particle size are flexibly adjusted. The combustion conditions and the burning effect are good, and the combustion characteristics of the oxygen urgently needed for the rapid precipitation of the volatile matter of the biomass fuel for the intense combustion are timely supplemented. The combustion conditions, combustion effects and boiler thermal efficiency are greatly improved, the furnace temperature gradient is uniform, the air distribution is uniform, and local high-temperature combustion is effectively prevented, and NO X and SO X The initial emission concentration is greatly reduced; the energy saving and environmental protection effects are obvious.

[0026] 5. Under the action of the downward-inclined feeding wind, an air cushion is formed at the bottom of the material guide cylinder and the drop port, which is conducive to supporting, broadcasting and uniform feeding of materials. The downward-pressure pressing wind forms a downward flow trend in this area, and the upward-inclined broadcasting wind forms an upward flow trend in this area. At the same time, under the suction effect of the negative pressure at the furnace outlet, the downward-pressure pressing wind and the upward-inclined broadcasting wind cooperate with each other to form a positive pressure sealing barrier effect on the feeding port area, thereby strengthening the cooling and blocking isolation effect of the furnace flame in this area. Therefore, the pressing wind and the broadcasting wind can effectively block the furnace flame from spraying out of the furnace and prevent the material guide device from backfiring; at the same time, oxygen is also added in time to meet the combustion needs of biomass fuel.

[0027] 6. The outer sides of the guide barrel are fixed by welding with heat-resistant metal rivets in the castable or on the heated surface to prevent deformation and warping of the guide barrel and its rear end, and to prevent the fixing device of the guide barrel from protruding inside the guide barrel to cause material hanging and blockage. This structure can effectively prevent the guide barrel from being deformed by heat and affecting the feeding. At the same time, it also effectively solves the problem that the rough, uneven surface of the castable at the material inlet has a large resistance, which blocks the fuel, causing poor material discharge and easy accumulation at the material inlet, causing flashback combustion; it also effectively avoids the wear of the biomass fuel on the material inlet, making the operation safer and conducive to the long-term safe and stable operation of the boiler.

[0028] 7. The broadcasting air chamber and the pressure air chamber are connected to the high-pressure secondary air through their respective interfaces, and are independently fine-tuned through valves; the landing point and the material-evening effect of the biomass fuel are adjusted by adjusting the momentum and nozzle flow rate of the feeding air and the broadcasting air; the combustion conditions and the suspended combustion ratio of the biomass fuel with lighter weight or finer particle size are adjusted by adjusting the momentum and nozzle flow rate of the feeding air, the broadcasting air and the pressure air to achieve the best combustion and operation effect; by independently adjusting the air volume of the feeding air, the broadcasting air chamber and the pressure air chamber, the oxygen in the feeding port area can be replenished in time and accurately to meet the fuel characteristic requirements of the biomass, and the positive pressure sealing effect at the feeding port can be improved to prevent backfire and fuel backfire, thereby ensuring feeding safety.

[0029] 8. The diversion interface device has a simple structure, no moving and transmission parts, and is particularly low in production cost, making it very suitable for large-scale promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the present invention;

[0031] Figure 2 It is a schematic diagram of the cross-sectional structure of the material guide cylinder of the present invention;

[0032] Figure 3 It is a schematic structural diagram of the material guiding cylinder in the inclined state of the present invention.

[0033] In the figure: 1 broadcasting air interface, 2 lining plate, 3 feeding air chamber, 4 material guide interface, 5 material guide cylinder, 6 pressing air interface, 7 pressing air chamber, 8 feeding air nozzle, 9 material guide bottom plate, 10 broadcasting air chamber, 11 reinforcement ribs, 12 broadcasting air nozzle, 13 pressing air nozzle, 14 casting material. DETAILED DESCRIPTION

[0034] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0035] See also Figure 1-3The present invention provides a technical solution: a flow guide interface device for feeding a biomass boiler, comprising a material guide cylinder 5, a material pressing air chamber 7 and a material broadcasting air chamber 10, a bottom plate flow guide structure is arranged at the bottom of the material guide cylinder 5, and the bottom plate flow guide structure is composed of a material guide bottom plate 9 and a liner 2, the material guide bottom plate 9 is located at the rear end of the material guide cylinder 5, the liner 2 is located at the front end of the material guide cylinder 5, the material guide bottom plate 9 is arranged to be a downwardly inclined "nose" structure with two sides folded downward, the inclination angle is set to α, and the material guide bottom plate 9 The nose height of the feeding port terminal is set to H, that is, the middle position is high, the two sides are folded downward, and the transition is smooth, and they are inclined downward and extended toward the furnace, so as to form a "nose"-shaped material guide bottom plate 9 that is gradually lowered and gradually contracted on both sides of the furnace. The material broadcasting air chamber 10 is located at the bottom of the material guide cylinder 5, and the rear end of the material broadcasting air chamber 10 is inclined toward the material guide cylinder 5. This structure forms an upward-curved material broadcasting air nozzle 12 with a low front and a high back, so as to enhance momentum and increase wind speed. The "nose"-shaped guide bottom plate 9 cooperates with the broadcasting air chamber 10 to form a broadcasting air nozzle 12 with a large center and small sides; the guide structure of the "nose"-shaped guide bottom plate 9 is adopted, so that the fuel enters the guide cylinder 5 and is gradually and naturally diverted to the two sides along the guide bottom plate 9, and the downward-inclined "nose"-shaped guide structure with a high center and low sides makes it easier for the fuel to be diverted to the two sides, thereby solving the problem that the fuel is more in the middle position near the feed port and less on both sides in the traditional feeding method, thereby causing the fuel to be unevenly distributed in the furnace, and even if the traditional lower broadcasting air is increased, it is difficult to broadcast, and the uneven feeding situation is difficult to overcome; the "nose"-shaped guide bottom plate 9 cooperates with the broadcasting air chamber 10 to form a "nose"-shaped broadcasting air nozzle 12 with a large center and small sides and gradually narrowing width on both sides, so that the air volume in the middle is large and the air volume on both sides is small, which is more conducive to broadcasting and even feeding, so that the feed can be evenly broadcast and scattered on the combustion equipment, which is conducive to improving the combustion condition and improving the boiler combustion efficiency and boiler thermal efficiency.

[0036] The "nose"-shaped guide bottom plate 9 is high in the middle and low on both sides, and the width of the two sides gradually narrows and has a downward inclination angle, which is the same as the natural falling trend of the fuel, is more conducive to the falling of the fuel, is less likely to cause fuel stagnation, and is more conducive to the fuel being evenly distributed to both sides, resulting in a better even distribution effect.

[0037] A material guide interface 4 is provided at the front end of the material guide cylinder 5, and a lining plate 2 is provided between the front end of the material guide bottom plate 9 and the material guide interface 4. The width of the lining plate 2 is consistent with the width of the material guide bottom plate 9, and the lining plate 2 is inclined toward the nose-shaped starting point direction of the material guide bottom plate 9 to form a downward pressure feeding air nozzle 8 which is high in front and low in the back, and the lining plate 2 covers the front end of the material guide bottom plate 9.

[0038] The lining plate 2 is communicated with the material broadcasting air chamber 10 to form a feeding air chamber 3 with a feeding air nozzle 8. The connecting air opening between the feeding air chamber 3 and the material broadcasting air chamber 10 is located at the front end of the lining plate 2 and away from the feeding air nozzle 8. The feeding air nozzle 8 is connected to the lining plate 2 and the material guide bottom plate 9 through the reinforcing ribs 11.

[0039] The inclined structure of the lining plate 2, which is higher in the front and lower in the back, is conducive to the natural sliding of the feed into the furnace by gravity, preventing it from being retained and accumulated at the material guide port. At the same time, a downward pressure feed air nozzle 8 is formed at its end. Under the action of the high-speed feed air, on the one hand, an air cushion is formed at the bottom of the material guide cylinder 5, which is conducive to the flow and uniformity of the fuel. On the other hand, under the downward pressure and high-speed conveyance of the feed air nozzle 8, the feed is smoothly delivered into the furnace for combustion. At the same time, it also enhances its functions of feeding, uniforming, adjusting the landing position of the biomass fuel, the combustion conditions and the suspended combustion ratio, and the positive pressure sealing function of the broadcasting air.

[0040] An upward-curved broadcasting air interface 1 is provided at the bottom of the broadcasting air chamber 10. The feeding air of the feeding air chamber 3 is drawn from the broadcasting air chamber 10 or an independent feeding air introduction is provided. The feeding air introduction structure can be provided according to specific circumstances.

[0041] The middle width of the broadcasting air nozzle 12 is set to be the nose width B, the width of the broadcasting air nozzle 12 is set to be A, and the ratio of the nose width B to the width A of the broadcasting air nozzle 12, ie B / A=0.1-0.3.

[0042] Nose height H=0.1-0.3 meters.

[0043] Inclination angle α=0-15°.

[0044] The furnace outlets of the broadcasting air chamber 10 and the pressing air chamber 7 are arranged to be inclined toward the guide cylinder 5 and to be contracted by the guide cylinder 5, forming a high-speed jet with an upward supporting and downward pressing effect, while also correspondingly increasing the air momentum and strengthening the entrainment effect, which is beneficial to enhancing the upward supporting and broadcasting effects and the downward pressing effect, and is beneficial to spreading the fuel and evenly delivering it into the furnace, preventing the fuel from accumulating against the wall at the drop port and causing incomplete combustion, thereby affecting the combustion effect; at the same time, the high-speed nozzle airflows of the broadcasting air chamber 10 and the pressing air chamber 7 cooperate with each other to form a local low-temperature positive pressure zone near the drop port, which can effectively block the furnace flame from spraying outward, prevent the feeding device from backfiring, and prevent the hot flue gas from backflowing; in order to increase the rigidity of the nozzle, a plurality of groups of reinforcing ribs 11 are used for reinforcement at the broadcasting air nozzle 12 and the pressing air nozzle 13.

[0045] The rear end of the pressing air chamber 7 is inclined toward the material guide cylinder 5, and together with the top plate of the material guide cylinder 5, forms a downward-pressure pressing air nozzle 13 which is high in the front and low in the back. The pressing air nozzle 13 enhances the air momentum and increases the nozzle wind speed, effectively preventing the fuel with lighter weight or finer particle size from directly escaping into the upper part of the furnace for combustion, which is not conducive to the burning of the fuel. At the same time, oxygen is also replenished in time, which is more suitable for the oxygen problem required for the rapid precipitation and combustion of the volatile matter of the biomass fuel, is more conducive to the combustion and burnout of the fuel, and improves the thermal efficiency of the boiler. A pressing air interface 6 is provided on the pressing air chamber 7.

[0046] Under the action of the downward-inclined feeding wind, an air cushion is formed at the bottom of the material guiding cylinder 5 and the drop port, which is beneficial to supporting, broadcasting and uniform feeding of materials, while the downward-pressure pressing wind forms a downward flow trend and state in this area, and the upward-curved broadcasting wind forms an upward flow trend and state in this area. At the same time, under the suction effect of the negative pressure at the furnace outlet, the downward-pressure pressing wind and the upward-curved broadcasting wind cooperate with each other to form a positive pressure sealing barrier effect on the feeding port area, and strengthen the cooling and blocking isolation effect of the furnace flame in this area. Therefore, the pressing wind and the broadcasting wind can be strengthened to effectively block the furnace flame from spraying out of the furnace, thereby preventing the feeding device from backfiring; at the same time, oxygen is also added in time to meet the combustion requirements of biomass fuel.

[0047] The shell of the material guide cylinder 5 is made of heat-resistant and wear-resistant stainless steel, and the rear end of the material guide cylinder 5 extends to the furnace, and the rear end of the material guide cylinder 5 is flush with the edge of the castable 14 inside the furnace. Specifically, the material guide cylinder 5 is directly inserted into the furnace, flush with the edge of the castable in the furnace, and fixed near the edge to prevent the feed port from deforming. The outer periphery of the material guide cylinder 5 is fixed by welding with heat-resistant metal rivets in the castable or on the heating surface to prevent the material guide cylinder and its rear end from deforming and warping, and also prevent the material guide cylinder from The fixing device protrudes from the inside of the material guide cylinder 5 and causes material hanging and blockage, and the shell fixing device of the material guide cylinder 5 is strictly prevented from protruding from the inside of the material guide cylinder 5 and causing material hanging, so as to prevent the material guide cylinder 5 from being deformed by heat and affecting the feeding. At the same time, it also effectively solves the problem that the surface of the material port pouring material 14 is rough, not smooth, and has great resistance, which blocks the fuel and causes poor material discharge, and is easy to accumulate at the material port and cause flashback combustion; it also effectively avoids the wear of the biomass fuel on the material port, and the operation is safer, which is conducive to the long-term safe and stable operation of the boiler.

[0048] The broadcasting air chamber 10 and the pressing air chamber 7 are connected to the high-pressure secondary air through their respective interfaces and are adjusted independently. The landing point and the material uniformity effect of the biomass fuel are adjusted by adjusting the momentum and nozzle flow rate of the feeding air chamber 3 and the broadcasting air chamber 10. The combustion condition and the suspended combustion ratio of the biomass fuel with lighter mass or finer particle size are adjusted by adjusting the momentum and nozzle flow rate of the feeding air chamber 3, the broadcasting air chamber 10 and the pressing air chamber 7 to achieve the best combustion and operation effect. By independently adjusting the air volume of the feeding air chamber 3, the broadcasting air chamber 10 and the pressing air chamber 7, the oxygen in the feeding port area can be replenished in time and accurately to meet the fuel property requirements of the biomass, and the positive pressure sealing effect at the feeding port can be improved to prevent the fuel from backfiring and ensure feeding safety.

[0049] The material guiding cylinder 5 can be tilted downward as a whole, and the angle is set to β, β=0-60°. The tilt angle of the flow guiding interface device can be set as required to obtain the required feeding and material distribution and energy-saving and environmental protection effects.

[0050] The flow guide interface device is not only applicable to layer-fired boilers, but also to fluidized bed boilers and coal-fired boilers, which are also within the protection scope of this patent.

[0051] The feeding air chamber 3, the broadcasting air chamber 10, the pressing air chamber 7, and the shapes of their respective air outlets can be changed in various ways, but as long as the principles and effects adopted are similar, they are all within the protection scope of this patent.

[0052] The basic principles, main features and advantages of the present invention are shown and described above. Without departing from the spirit and scope of the present invention, the present invention may also be subject to various changes and improvements, which all fall within the scope of the present invention to be protected.

Claims

1. A biomass boiler feed guide interface device, comprising a feed guide cylinder (5), a feed pressing air chamber (7) and a feed broadcasting air chamber (10), characterized in that: A bottom plate flow guide structure is provided at the bottom of the material guide cylinder (5), and the bottom plate flow guide structure is composed of a material guide bottom plate (9) and a lining plate (2). The material guide bottom plate (9) is located at the rear end of the material guide cylinder (5), and the lining plate (2) is located at the front end of the material guide cylinder (5). The material guide bottom plate (9) is arranged to be a downwardly inclined "nose" shaped structure with two sides folded downward, and the inclination angle is set to α. The nose height of the feeding port terminal of the material guide bottom plate (9) is set to H, and it extends obliquely downward in the direction of the furnace. The material broadcasting air chamber (10) is located at the bottom of the material guide cylinder (5), and the rear end of the material broadcasting air chamber (10) is inclined in the direction of the material guide cylinder (5). The material guide bottom plate (9) and the material broadcasting air chamber (10) cooperate to form a material broadcasting air nozzle (12) with a large middle part and small two sides. A material guide interface (4) is provided at the front end of the material guide cylinder (5), and the lining plate (2) is arranged between the front end of the material guide bottom plate (9) and the material guide interface (4). The width of the plate (2) is consistent with the width of the material guide bottom plate (9), the lining plate (2) is inclined toward the nose starting point of the material guide bottom plate (9), forming a feeding air nozzle (8) that is high in the front and low in the back, and the lining plate (2) covers the front end of the material guide bottom plate (9), the pressing air chamber (7) is arranged on the upper part of the material guide cylinder (5), the rear end of the pressing air chamber (7) is inclined toward the material guide cylinder (5), and the pressing air chamber (7) and the material guide cylinder ( 5) cooperate to form a material pressing air nozzle (13) which is higher in the front and lower in the back; the lining plate (2) is connected to the material broadcasting air chamber (10) to form a material feeding air chamber (3) with a material feeding air nozzle (8); the connecting air opening between the material feeding air chamber (3) and the material broadcasting air chamber (10) is located at the front end of the lining plate (2) and away from the material feeding air nozzle (8); the material feeding air nozzle (8) is connected to the lining plate (2) and the material guiding bottom plate (9) through the reinforcing ribs (11).

2. The flow guide interface device for feeding a biomass boiler according to claim 1, characterized in that: A broadcasting air interface (1) is provided at the bottom of the broadcasting air chamber (10), and the feeding air of the feeding air chamber (3) is drawn from the broadcasting air chamber (10) or an independent feeding air introduction is provided.

3. The flow guide interface device for feeding a biomass boiler according to claim 1, characterized in that: The middle width of the broadcasting air nozzle (12) is set as the nose width B, the width of the broadcasting air nozzle (12) is set as A, and the ratio of the nose width B to the width A of the broadcasting air nozzle (12), that is, B / A=0.1-0.

3.

4. The flow guide interface device for feeding a biomass boiler according to claim 1, characterized in that: Nose height H=0.1-0.3 meters.

5. The flow guide interface device for feeding a biomass boiler according to claim 1, characterized in that: Inclination angle α=0-15°.

6. The flow guide interface device for feeding a biomass boiler according to claim 1, characterized in that: The shell of the material guide cylinder (5) is made of heat-resistant and wear-resistant stainless steel material, and the rear end of the material guide cylinder (5) extends to the furnace, the rear end of the material guide cylinder (5) is flush with the edge of the castable (14) inside the furnace, and the outer periphery of the material guide cylinder (5) is fixed to the material guide cylinder (5) by welding with heat-resistant metal rivets in the castable or on the heating surface.

7. The flow guide interface device for feeding a biomass boiler according to claim 1, characterized in that: The material pressing air chamber (7) and the top plate of the material guiding cylinder (5) form a material pressing air nozzle (13) which is higher in the front and lower in the back. The material pressing air chamber (7) is provided with a material pressing air interface (6).

8. The flow guide interface device for feeding a biomass boiler according to claim 1, characterized in that: The material guiding cylinder (5) can be tilted downward as a whole, and the angle is set to β, β=0-60°.

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