Biomass combustion furnace end and combustor

Abstract

The burner comprises a stock bin, an air gathering bin and a burner body, the burner body comprises a burning cavity, one end of the burning cavity is provided with a function distribution plate, the function distribution plate is provided with a feeding port, a primary air inlet, a secondary air inlet and a tertiary air inlet, the top of the burning cavity is provided with a tertiary burning head, and the top of the tertiary burning head is provided with a secondary air inlet. A primary combustion area, a secondary combustion area and a tertiary combustion area are arranged in the combustion chamber, the primary combustion area is located at the feed port, and the tertiary combustion area is located at the tertiary combustion head; a primary combustion-supporting air duct, a secondary combustion-supporting air duct and a tertiary combustion-supporting air duct are arranged in the combustion cavity, and the primary air inlet, the secondary air inlet and the tertiary air inlet are connected with the primary combustion-supporting air duct, the secondary combustion-supporting air duct and the tertiary combustion-supporting air duct respectively. According to the combustor, three-time combustion of fuel is achieved in a three-time independent air supply mode, the combustion efficiency is effectively improved, heat dissipated in the combustion process can preheat combustion-supporting air, the combustibility is enhanced, and meanwhile the combustion efficiency of the fuel can be further improved.

Description

Technical Field

[0001] The invention relates to the technical field of biomass burners, and in particular to a biomass burning stove head and a burner. Background Art

[0002] With the development of the "dual carbon" goal process, the treatment and application of biomass, especially biomass that has been considered as agricultural (forestry) solid waste in the past, has attracted increasing attention. At present, the output of straw (branch) is the largest category of agricultural (forestry) biomass. Using this type of biomass as fuel has become a part of agricultural production. The matching burners are emerging in an endless stream and have become a common agricultural machinery.

[0003] CN108613169A discloses a biomass particle burner, which is provided with a main combustion chamber, an ash chamber and an insulation chamber, wherein a feed port is provided at one end of the main combustion chamber, and the other end of the main combustion chamber is connected with the ash chamber; the insulation chamber is arranged on the side and below the main combustion chamber, an insulation chamber air inlet is provided at one end of the insulation chamber, and an insulation chamber air outlet connected with the insulation chamber is provided at the bottom of the main combustion chamber; a mesh plate is provided in the main combustion chamber, and the mesh plate is located above the insulation chamber air outlet; an opening is provided on the wall of the main combustion chamber below the feed port, and a mesh plate driving end is provided at one end of the mesh plate, which extends out of the main combustion chamber through the opening; the mesh plate driving end is connected to a motor and a transmission mechanism thereof that can drive the mesh plate to move back and forth.

[0004] CN112443854A discloses a biomass pellet combustion device, including a main box body, a push tube, an air supply tube, a collecting box and a combustion box, wherein a feeding funnel is fixedly installed on the top of the main box body, and universal wheels are fixedly installed around the bottom end of the main box body, and a combustion box is fixedly installed on the right side inside the main box body, a collecting box is fixedly installed on the top of the combustion box, the bottom end of the feeding funnel extends to the inside of the main box body where a storage box is fixedly installed, a push tube is fixedly installed on the bottom end of the storage box laterally, and an air supply tube is fixedly installed on the left side of the combustion box below the push tube, and an ignition tube is fixedly installed on the right side of the combustion box, and a sealing door is movably installed on the lower right side of the front end of the main box body.

[0005] CN109307260A discloses a plant straw pellet burner, comprising a combustion furnace body, a feeding device, a grate device and an ash discharge device; a furnace is formed inside the combustion furnace body, and a fire outlet connected to the furnace is provided on the side wall; the feeding device is installed on the outside of the combustion furnace body, and one end is connected to the furnace; the grate device is installed in the furnace, located below the outlet end of the feeding device, and can carry the plant straw pellets to move in the direction away from the outlet end of the feeding device; the ash discharge device is installed below the combustion furnace body and connected to the furnace, and is used to discharge the carbon ash in the furnace.

[0006] The burner air inlet design in the above patent is simple, the combustion is incomplete, the fuel utilization rate is low, the fire-keeping feed amount and the minimum heating amount are too large, and it is easy to go out or cause temperature overshoot when the fire is kept at a low fire. At present, it can only burn formed biomass pellet fuel, but not just crushed biomass crushed material, and does not consider the subsequent utilization of ash and charcoal after the fuel combustion. Summary of the invention

[0007] In response to the above problems, the present invention provides a biomass combustion stove head and burner, which respectively supply oxygen to the combustibles at three combustion points through three combustion-supporting air ducts, thereby improving the combustion efficiency. The combustion-supporting air ducts are located around the wall of the combustion chamber, and the heat generated by the combustion of the fuel can be used to preheat the combustion-supporting air in each combustion-supporting air duct, thereby enhancing the combustibility and further improving the fuel combustion efficiency.

[0008] Specifically, the present invention provides a biomass combustion stove head, comprising: a combustion cavity, one end of which is provided with a function distribution plate, the function distribution plate is provided with a feed inlet, a primary air inlet, a secondary air inlet and a tertiary air inlet, the top of the combustion cavity is provided with a tertiary combustion head, the interior of which is provided with a primary combustion zone, a secondary combustion zone and a tertiary combustion zone, the primary combustion zone is located at the feed inlet, the secondary combustion zone is located below and in front of the primary combustion zone, and the tertiary combustion zone is located at the tertiary combustion head and the top of the cavity;

[0009] A primary combustion-supporting air duct, a secondary combustion-supporting air duct and a tertiary combustion-supporting air duct are provided in the combustion chamber, the primary air inlet is connected to the primary combustion-supporting air duct, the secondary air inlet is connected to the secondary combustion-supporting air duct, and the tertiary air inlet is connected to the tertiary combustion-supporting air duct. The primary combustion-supporting air duct is used to supply air to the primary combustion zone, the secondary combustion-supporting air duct is used to supply air to the secondary combustion zone, and the tertiary combustion-supporting air duct is used to supply air to the tertiary combustion zone.

[0010] Furthermore, a primary combustion table is provided at the feed port, a primary air inlet is provided on the primary combustion table, and the primary combustion-supporting air duct is located below the primary combustion table; a secondary combustion plate is provided directly in front and below the primary combustion table away from the feed port, a secondary air inlet is provided on the secondary combustion plate, and the secondary combustion-supporting air duct is located below the secondary combustion plate; after the fuel enters the primary combustion table through the feeding pipe, it gradually accumulates and burns on the rear of the primary combustion table, and the fuel that has completed the primary combustion but has not been burned falls onto the secondary combustion plate for secondary combustion after the primary combustion table is filled with fuel and under the thrust of continuous feeding.

[0011] Furthermore, the tertiary combustion-supporting air duct is located on two sides and the top of the upper half of the combustion chamber, and the tertiary combustion head is a cone with tertiary air inlet holes around it, and the tertiary combustion head is larger at the bottom and smaller at the top.

[0012] Furthermore, an ash and char removal device is provided in the combustion chamber, and the ash and char removal device comprises:

[0013] The ash and charcoal outlet is located at the end of the combustion chamber away from the feed inlet;

[0014] An ash and char removal plate is located above and falls on the secondary combustion plate and has the same shape as the secondary combustion plate. The ash and char removal plate is configured to move in a horizontal direction. When the ash and char removal plate contracts and stops moving, fuel falls from the primary combustion table onto the secondary combustion plate. When the ash and char removal plate moves and extends, fuel also falls from the primary combustion table onto the moving ash and char removal plate.

[0015] When removing ash, the ash removing plate moves toward the ash outlet end. The pushing, shoveling and carrying forces generated by the movement will prompt the bottom ash on the secondary combustion plate and the burning fuel to move forward. As the end of the ash removing plate's advancement stroke approaches, the ash that was last trapped at the ash outlet will be squeezed out of the combustion chamber. In addition, when the ash removing plate starts to move, the ash removing plate will push the fuel accumulated on the bottom layer of the junction of the primary combustion platform and the secondary combustion plate forward. Such a push will cause the fuel in the upper layer of the junction to lose support, sink and then fall on the ash removing plate moving forward and move with it. When the ash removing plate reaches the end of its advancement stroke, the ash removing plate will reset. When the reset process begins, the ash at the front end of the ash removing plate but not on the ash removing plate will remain at the ash outlet, and will be squeezed out in the same way when the ash removing plate moves to this point next time, while the ash and unburned fuel on the ash removing plate will retreat with the ash removing plate and gradually fall on the secondary combustion plate during the retreat process. Repeat this action in a reciprocating cycle.

[0016] Furthermore, an outlet cover plate is provided at the ash and charcoal outlet, the outlet cover plate is hinged to the combustion chamber, and the outlet cover plate is pushed by two left and right push rods, the roots of the two push rods are connected to the ash and charcoal removing plate push rods, when the ash and charcoal removing plate moves horizontally forward and backward, the two left and right outlet cover plate push rods also move forward and backward, thereby driving the outlet cover plate to open and close.

[0017] Furthermore, the ash and charcoal outlet cover plate is lifted up by a push rod linked to the ash and charcoal removing plate.

[0018] Furthermore, the primary air inlet is located below the feed inlet, there are two secondary air inlets, which are located below the primary air inlet, and the tertiary air inlets are located on the left, right and above the feed inlet.

[0019] Further, the primary air inlet and the secondary air inlets are vertically distributed one above the other and are separated by the secondary combustion plate. The primary air inlet is above, and the secondary air inlets are below. The primary air inlet and the two secondary air inlets are distributed in a "pin" shape. There are three tertiary air inlets, and the three tertiary air inlets are distributed in an "n" shape.

[0020] Further, the secondary air inlet holes are arranged in such a way that the air output gradually decreases from the end close to the primary combustion platform to the end far from the primary combustion platform.

[0021] The present invention also provides a biomass burner, which includes a fuel bin, a wind gathering bin, and the biomass burner head as described above. The wind gathering bin is docked with the biomass burner head. The fuel is fed from the fuel bin into the combustion cavity through the feeder from the feed inlet. The air given by the combustion-supporting fan gathers in the wind gathering bin and then is sent into the primary combustion-supporting air duct, the secondary combustion-supporting air duct, and the tertiary combustion-supporting air duct respectively from the primary air inlet, the secondary air inlets, and the tertiary air inlets according to the combustion requirements, providing three times of oxygen for the full combustion of the fuel.

[0022] Further, inside the end of the wind gathering bin close to the biomass burner head, there are a secondary combustion-supporting air pneumatic baffle and a tertiary combustion-supporting air pneumatic baffle. Both the secondary combustion-supporting air pneumatic baffle and the tertiary combustion-supporting air pneumatic baffle are configured to automatically open under the action of the combustion-supporting air, and the opening degree increases with the increase of the combustion-supporting air.

[0023] Working principle:

[0024] In the initial stage of ignition, the fuel in the fuel bin is fed into the primary combustion platform through the feeder and then ignited. The fuel undergoes primary combustion on the primary combustion platform, and here, part of the moisture in the fuel evaporates and the volatile components are released. Part of the fuel mixes with the released volatile components and air to reach the ignition concentration and temperature, completing the first-stage combustion task.

[0025] As the combustion requires, when the fuel supply is gradually increased, the fuel on the primary combustion platform will gradually accumulate. When it accumulates to a certain amount, the fuel that has completed the first-stage primary combustion task will roll onto the secondary combustion plate and continue to burn. At this time, the furnace temperature and the temperature of the fuel itself will further increase, and more volatile components will be released and ignited here, releasing heat and continuing to increase the furnace temperature. A large amount of solid fuel undergoes coking here and is heated to a relatively high temperature and burns violently. As the firepower requires, the combustion amount is further increased, and a large amount of fuel will gradually fill the primary combustion platform and the secondary combustion plate. At this time, the supply of the combustion-supporting air is increased.

[0026] The hot flue gas in the furnace surges, and the heat enriched in the fuel, furnace body, etc. is increasing. At this time, the temperature rises faster, the chemical reaction is more intense, and the furnace body is filled with high temperature, high pressure, and high expansion. Therefore, a state of hypoxia will appear in the conventional biomass combustion furnace, and the phenomenon of incomplete combustion and reduction coking will be aggravated. Some oxidized substances will be reduced again, and reducing gases such as carbon monoxide (CO) may be generated. Unfavorable conditions such as blue smoke, black smoke, and coking will occur successively, and the result is that the high-temperature flue gas cannot be completely burned, and it will enter the area without combustion conditions with other flue gases, and finally be discharged into the atmosphere along the flue. In order to solve and avoid this drawback to the greatest extent, the present invention sets a tertiary combustion zone as the third combustion point. The unburned or secondary reduced reducing combustible gas arrives at the upper part of the furnace body with the hot flow flue gas, and flows to the fire outlet and arrives at the tertiary combustion zone. Therefore, the third combustion-supporting oxygen provided by the three combustion-supporting air ducts enables the combustible gas arriving here to be smoothly burned for the third time here.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) The biomass burning stove head of the present invention realizes three-time combustion of fuel by three-time independent air supply, and effectively improves the fuel combustion efficiency.

[0029] (2) The three combustion-supporting air ducts are all located around the combustion chamber wall. The heat dissipated through the chamber wall during fuel combustion can preheat the combustion-supporting air in the combustion-supporting air duct, ensuring that the air supplied to the fuel for combustion is hot air. This can enhance the combustibility and further improve the fuel combustion efficiency.

[0030] (3) The primary combustion table and the ash and charcoal removal plate are separated, which can keep the fire-keeping feed amount and the minimum heat supply at the minimum. At the same time, when removing the ash and charcoal, the combustion point on the primary combustion table will not be disturbed. Therefore, when the fire is kept at a low fire, the probability of flameout or temperature overshoot will be greatly reduced, avoiding the problem of the conventional combustion furnace's ash cleaning device being located directly behind the fuel combustion point, disturbing the combustion point during ash cleaning and causing frequent flameouts.

[0031] (4) The ash and charcoal removal plate referred to in the present invention is quite different from the ash cleaning device of a conventional combustion furnace. The present invention emphasizes "ash and charcoal removal" rather than just "ash cleaning" or "slag removal". From the perspective of the use scenarios of biomass burners, almost all raw materials for biomass fuels come from rural areas. Crop straws and fruit and vegetable branches are beneficial products in rural areas. When they are burned, different degrees of burnout will produce ash and charcoal in different forms and quantities. These ash and charcoal are the best materials for returning fertile land to farmland and repairing cultivated land, and should be retained. The burner head of the present invention can control the degree of fuel burnout by adjusting the ratio of feed and ash and charcoal removal according to the differences in crop straws and fruit and vegetable branches, so as to maximize the control of the ratio of ash and charcoal produced, thereby meeting the needs of rural areas for collecting straw charcoal (wood ash) and returning it to the fields.

[0032] (5) The burner head of the present invention can not only burn biomass pellets, but also burn biomass crushed materials that are only crushed without forming. The burners of the prior art cannot burn biomass crushed materials. Therefore, the feed bin of the present invention has a conical feed opening, and a feed stirring device is provided in the feed bin. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the structure of the biomass combustion burner in Example 1;

[0034] Figure 2 This is a schematic diagram of the structure of the biomass burning burner in Example 1;

[0035] Figure 3 This is a schematic diagram of the structure of the biomass burning burner function distribution plate side in Example 1;

[0036] Figure 4 It is an exploded view of the biomass burning stove head in Example 1;

[0037] Figure 5 The exploded view of the wind collecting chamber and the furnace head in Example 1;

[0038] Figure 6 This is a schematic diagram of the combustion-supporting air distribution principle of the air collection bin in Example 1;

[0039] Figure 7 This is a schematic diagram of the air intake principle of the biomass burning burner in Example 1;

[0040] Figure 8 This is a schematic diagram of the combustion principle of the biomass burning burner in Example 1;

[0041] Fig. 9 It is a schematic diagram of the ignition stage of the biomass burning stove in Example 1;

[0042] Fig.10 A schematic diagram of the fuel in Example 1 falling onto the secondary combustion plate and continuing to burn;

[0043] Fig.11 Schematic diagram of the cleaning action in Example 1; wherein (a) is a schematic diagram of the state in which the bottom layer of ash and charcoal is cleaned to be retained at the ash and charcoal outlet; (b) is a schematic diagram of the state in which the ash and charcoal is cleaned out of the ash and charcoal outlet;

[0044] Fig.12 These are photos of ash and charcoal in different degrees of burnout.

[0045] Reference numerals:

[0046] 1- silo; 2- chassis; 3- wind gathering bin; 31- pneumatic damper for secondary combustion-supporting air; 32- pneumatic damper for tertiary combustion-supporting air; 33- partition; 4- furnace head; 41- function distribution plate; 411- feed port; 412- primary air inlet; 413- secondary air inlet; 414- tertiary air inlet; 415- ignition port; 416- auxiliary air inlet; 42- primary combustion table; 421- primary combustion-supporting air duct; 43- secondary combustion plate; 431- secondary combustion-supporting air duct; 432- secondary combustion-supporting air duct outer shell plate; 44- tertiary combustion head; 441- tertiary combustion-supporting air duct; 442- tertiary combustion-supporting air duct outer shell plate; 45- outlet cover plate; 46- ash and charcoal removal plate; 461- top rod; 47- furnace body inner liner; 5- stirring device. DETAILED DESCRIPTION

[0047] The present invention will be further described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0048] Example 1

[0049] like Figure 1 As shown, this embodiment provides a biomass burner, including a silo 1, a chassis 2, an air collecting bin 3, a burner 4 and a stirring device 5. A feeder, a combustion-supporting fan, an igniter, an ash and charcoal removal push rod motor, a fire viewing port, etc. are arranged in the chassis 2. The air collecting bin 3 is connected to one side of the functional distribution plate 41 of the burner 4. The fuel falls from the silo 1 into the feeder through the stirring of the stirring device 5 and the weight of the fuel itself. The fuel is fed into the combustion chamber through the feed port 411 on the functional distribution plate 41 through the feeder. The wind given by the combustion-supporting fan is gathered in the air collecting bin 3 and then fed into the burner 4 to provide oxygen for the combustion of the fuel.

[0050] Specifically, Figure 2-4As shown in the figure, the outer shell of the burner head 4 is composed of a function distribution plate 41, a secondary combustion air duct outer shell plate 432, a tertiary combustion air duct outer shell plate 442, and an ash and charcoal outlet cover plate 45. The interior is a combustion chamber. The function distribution plate 41 is provided with a feed port 411, a primary air inlet 412, a secondary air inlet 413, a tertiary air inlet 414, an ignition port 415, and an auxiliary air inlet 416. The feed port 411 is located in the middle of the function distribution plate 41. The primary air inlet 412 is directly below the feed port 411. The secondary air inlet 413 is divided into left and right halves, which are respectively located below and on both sides of the primary air inlet 412, and its overall shape is an arc-shaped "pin" shape. There are three tertiary air inlets 414, and the three tertiary air inlets 414 are distributed in an "ㄇ" shape on both sides and above the feed port 411. The ignition port 415 is arranged at the lower left corner of the feed port 411 for igniting the fuel on the primary combustion stage 42. A number of auxiliary air inlets 416 are arranged on both sides of the feed port 411 for further supplementing oxygen into the combustion chamber.

[0051] As Figure 5-6 shown, one end of the air gathering chamber 3 connected to the burner head 4 has the same shape as the function distribution plate 41, so that the combustion-supporting air in the air gathering chamber 3 can smoothly enter the burner head 4. Specifically, the air gathering chamber 3 is provided with an aluminum secondary combustion air pneumatic baffle 31 and a tertiary combustion air pneumatic baffle 32. The side sectional view of the secondary combustion air pneumatic baffle 31 is overall in a "V" shape. Its right end is hinged to the body of the air gathering chamber 3, and its left end extends in an arc shape towards the air inlet end, so that the left end of the secondary combustion air pneumatic baffle 31 is an open cavity structure. When there is no wind or the wind is small, the bottom end of the secondary combustion air pneumatic baffle 31 contacts the bottom of the air gathering chamber 3 to block the combustion-supporting air from entering the secondary combustion air duct 431; when the combustion-supporting air is large, the combustion-supporting air will act on the extended part, causing the secondary combustion air pneumatic baffle 31 to lift, so that the combustion-supporting air can enter the secondary combustion air duct 431 through the secondary combustion air outlet. The tertiary combustion air pneumatic baffle 32 is located at the top of the air gathering chamber 3. Its upper end is hinged to the top of the air gathering chamber 3. A partition 33 is arranged between the primary combustion air outlet and the tertiary combustion air outlet. The tertiary combustion air pneumatic baffle 32 is located between the top of the air gathering chamber 3 and the partition 33 and is inclined at a certain angle. When there is no wind or the wind is small, the tertiary combustion air pneumatic baffle 32 naturally falls to the partition 33 to block the combustion-supporting air from entering the tertiary combustion air duct 441; when the combustion-supporting air is large, the tertiary combustion air pneumatic baffle 32 will gradually be blown up, allowing the combustion-supporting air to enter the tertiary combustion air duct 441. Specifically, when the wind force is so small that it cannot blow the secondary combustion air pneumatic baffle 31 and the tertiary combustion air pneumatic baffle 32, most of the combustion-supporting air entering the air gathering chamber 3 can only enter the primary combustion air duct 421 from the primary combustion air outlet. As the air volume increases, the secondary combustion air pneumatic baffle 31 and the tertiary combustion air pneumatic baffle 32 are gradually blown up, and the air output of the secondary combustion air outlet and the tertiary combustion air outlet gradually increases.

[0052] As Figure 7As shown, a primary combustion table 42, a secondary combustion plate 43, a tertiary combustion head 44, a furnace inner shell 47 and an ash and charcoal removal device are provided in the combustion chamber. The primary combustion table 42 is located at the feed port 411, and is in a "┐" shape as a whole, so that a primary combustion-supporting air duct 421 is formed between it and the secondary combustion plate 43, and a plurality of primary air inlet holes are provided on it, so that the primary combustion-supporting air entering the primary combustion-supporting air duct 421 through the primary air inlet 412 can go up to the primary combustion table 42 through the primary air inlet hole, thereby providing sufficient oxygen for the combustion of fuel on the primary combustion table 42.

[0053] The secondary combustion plate 43 is located below the primary combustion table 42, and extends from one side of the functional distribution plate 41 to the side of the ash and charcoal outlet cover plate 45. Below it is the secondary combustion-supporting air duct outer shell plate 432. A secondary combustion-supporting air duct 431 is formed between the functional distribution plate 41 and the secondary combustion-supporting air duct outer shell plate 432. A plurality of secondary air inlet holes are provided on the secondary combustion plate 43. The secondary combustion air entering the secondary combustion air duct 431 through the secondary air inlet 413 can ascend to the secondary combustion plate 43 through the secondary air inlet hole, thereby providing the fuel that rolls onto the secondary combustion plate after completing the primary combustion with the oxygen required for further combustion. Preferably, the secondary air inlet holes can be arranged in a manner that the air volume gradually decreases from one end close to the primary combustion table 42 to one end of the outlet cover plate 45, such as increasing the density (number) of the secondary air inlet holes at one end of the primary combustion table 42 or increasing the aperture of the secondary air inlet holes at one end of the primary combustion table 42, etc. By increasing the air intake volume at one end of the primary combustion table 42, the secondary combustion-supporting air is more concentrated in the area where the fuel is accumulated, so that the combustion is more concentrated.

[0054] The tertiary combustion head 44 is located on the furnace body liner 47 above the secondary combustion plate 43. A tertiary combustion-supporting air duct 441 is formed between the furnace body liner 47 and the tertiary combustion-supporting air duct outer shell plate 442. The tertiary combustion head 44 is in the shape of a closed cone to make the outlet flame more concentrated. A number of tertiary air inlet holes are provided on the side wall of the cone. The tertiary combustion-supporting wind entering the tertiary combustion-supporting air duct 441 through the tertiary air inlet 414 can enter the tertiary combustion area through the tertiary air inlet holes, thereby providing oxygen for the tertiary combustion of the flue gas generated after the primary and secondary combustion.

[0055] The heat generated by the three combustion processes of the fuel in the three areas is transferred to the primary combustion-supporting air duct 421, the secondary combustion-supporting air duct 431 and the tertiary combustion-supporting air duct 441 through the primary combustion table and the secondary combustion plate, as well as the conduction effect of the wall of the inner tank 47 of the furnace body. This part of the heat will heat the incoming air in each area, thereby avoiding the negative impact of the low incoming air temperature and ensuring sufficient combustion.

[0056] like Figure 8-9As shown, at the initial stage of ignition, the fuel in the silo 1 is stirred by the stirring device 5 and falls into the feeder due to its own weight. After being sent to the primary combustion table 42 from the feed port 411 on the functional distribution plate 41 by the feeder, the high-temperature air of the ignition rod is blown out from the ignition port 415 to the fuel on the primary combustion table for ignition. The ignited fuel undergoes a primary fuel combustion on the primary combustion table 42, and a primary combustion-supporting air is sent from the primary combustion-supporting air duct 421 to the primary combustion table 42, where part of the water in the fuel evaporates and the volatile matter precipitates. Part of the fuel is mixed with the precipitated volatile matter and air to reach the ignition concentration and temperature, completing a primary combustion.

[0057] like Fig.10 As shown, as the need for combustion increases, when the fuel supply is gradually increased, the fuel on the primary combustion table 42 will gradually accumulate. When it accumulates to a certain amount, the fuel that completes the first stage of primary combustion will fall onto the secondary combustion plate to continue burning. At this time, the furnace temperature and the temperature of the fuel itself will further increase. More volatiles will precipitate and ignite here, releasing heat, continuing to increase the temperature in the combustion chamber. A large amount of solid fuel will be coked here and heated to a higher temperature and burn violently.

[0058] like Figure 8 As shown, the unburned or secondary reduced reducing combustible gas reaches the upper part of the furnace body along with the heat flow, and flows to the fire outlet of the tertiary combustion head 44. After reaching the tertiary combustion area, the tertiary combustion-supporting air duct 441 provides sufficient oxygen for it, so that the combustible gas reaching this area is burned for the third time. The present invention realizes the tertiary combustion of fuel by three independent air supplies, which effectively improves the fuel combustion efficiency.

[0059] Furthermore, the ash and char removal device includes: an ash and charcoal outlet and an ash and charcoal removal push plate 46. The ash and charcoal outlet is located at the outlet cover plate 45. The outlet cover plate 45 is hinged to the combustion chamber. The ash and charcoal removal push plate 46 has the same shape as the secondary combustion plate 43 and is attached to the upper surface of the secondary combustion plate 43. The ash and charcoal removal push plate 46 is configured to move along the upper surface of the combustion plate 43. The fuel falls from the primary combustion table 42 onto the secondary combustion plate for secondary combustion, and the secondary combustion forms ash and charcoal. Two push rods 461 are provided on both sides of the ash and charcoal removal push plate 46, which extend toward the outlet cover plate 45 as the ash and charcoal removal push plate moves, and lifts up the outlet cover plate 45. Figure 7 and Fig.11As shown, when removing charcoal, the charcoal removal push plate 46 moves toward the charcoal outlet end. The pushing, shoveling, and carrying forces generated by the movement will cause the bottom charcoal on the secondary combustion plate and the burning fuel to move forward. As the charcoal removal push plate 46 approaches the end of the advancement stroke, the charcoal that was last trapped at the charcoal outlet will be squeezed out of the combustion chamber. In addition, when the charcoal removal plate 46 starts to move, the burning fuel accumulated at the junction of the primary combustion platform and the secondary combustion plate will fall on the charcoal removal plate 46 moving forward due to the loss of the lower support, and move with it. When it reaches the end of the advancement stroke, the charcoal removal plate 46 automatically retreats and resets. At the beginning of the retreat and reset process, the ash and charcoal at the front end of the ash and charcoal removing plate 46 but not on the ash and charcoal removing plate, including the bottom ash and charcoal and some unburned fuel, will be retained at the ash and charcoal outlet, and will be squeezed out in the same way when the ash and charcoal removing plate 46 runs next time. The bottom ash and charcoal and unburned fuel on the ash and charcoal removing plate 46 will retreat with the ash and charcoal removing plate, and gradually fall onto the secondary combustion plate during the retreat process, and the action will be repeated in this reciprocating cycle.

[0060] The ash outlet cover plate 45 provided at the ash outlet is hinged to the combustion chamber. When the ash removal plate 46 moves toward the ash outlet, the ash retained at the ash outlet will be squeezed and pressed against the outlet cover plate 45. When the ash removal plate 46 moves to a certain extent, two push rods 461 connected to the push rod of the ash removal plate 46 and arranged on the left and right sides will extend from both sides of the secondary combustion air duct to lift up the outlet cover plate 45. The ash retained and squeezed at the ash outlet will fall out of the furnace body from the ash outlet and enter the ash collection bin. When the ash removal plate 46 reaches the end of the thrust stroke, it will automatically retreat and reset. At the same time, the push rod 461 that lifts up the ash outlet cover plate 45 will also retract, and the ash outlet cover plate 45 that loses the push force will immediately fall down and close the ash outlet.

[0061] It should be noted that the word "ash and charcoal" is used in the present invention, which is different from the "ash and slag" used in other burners in the past. This is because the burner associated with the present invention is based on agricultural (forestry) straw (branches) as the main fuel source. When burning this type of fuel, it is considered that straw and branches are the main source of biochar (wood ash). The burned out fuel is "ash", and the unburned fuel is "charcoal". "Charcoal" is the best material for improving farmland soil and agricultural and forestry ecology, while "ash" is the component of fuel that has been burned out. For farmland and forest land, its nutrients and conditioning properties are far inferior to "charcoal". When agricultural and forestry production needs to generate "biochar" while burning biomass for heating, unburned charcoal can be obtained by speeding up the feed and adjusting the ratio of feed and ash and charcoal removal time. The states of ash and charcoal at each stage are as follows: Fig.12 shown.

[0062] Example 2

[0063] The burner head of the present invention was tested for burning tobacco stem biomass fragments, and the results were as follows:

[0064] Table 1 Combustion performance test table of the stove head of the present invention burning tobacco stalk biomass fragments

[0065]

[0066] Table 2 No-load test table of the present invention's burner head burning tobacco stalk biomass fragments to heat the drying room

[0067]

[0068]

[0069] Table 3 Test table of the present invention of burning tobacco stalk biomass fragments in the furnace head for heating the flue-curing room to bake tobacco leaves

[0070]

[0071]

[0072] Table 4 Statistical analysis of energy consumption of tobacco leaves baked in different heating forms

[0073]

[0074] Note: 1. Biomass pellets and tobacco stem fragments biomass use 3 workers (three shifts) to look after 20 curing houses for 50 days, and the salary is calculated at 150 yuan per person per day; pure electric direct heating and heat pump curing houses use 2 workers (two shifts) to look after 30 curing houses for 50 days, and the salary is calculated at 150 yuan per person per day. The annual labor consumption of each curing house in the table is estimated. 2. Biomass pellets use biomass pellet integrated burners, and tobacco stem fragments biomass use the project team's special tobacco stem fragments integrated burner.

[0075] Table 5 Comparison of cost, energy consumption and labor of different heating equipment in a single tobacco curing house

[0076]

[0077] Note: 1. The heat pump curing room is calculated based on the assumption that each room is loaded with 4,000 kg of fresh tobacco leaves each time, and each room produces an average of 3,000 kg of dry tobacco per year; 2. The other curing rooms are calculated based on the assumption that each room is loaded with 4,600 kg of fresh tobacco leaves each time, and each room produces an average of 3,500 kg of dry tobacco per year; 3. The energy consumption costs of all curing rooms include the electricity costs of circulating fans; 4. Based on: 3 workers (three shifts) are employed in the coal-fired curing room to look after 5 curing rooms for 60 days; 3 workers (three shifts) are employed in the biomass curing room for biomass pellets and tobacco stalk fragments to look after 20 curing rooms for 60 days; 2 workers (two shifts) are employed in the pure electric direct heating and heat pump curing rooms to look after 30 curing rooms for 60 days. The estimated labor force of each curing room in the table for ten years is given; 5. The average daily wage for ten years is calculated as 180 yuan per person; 6. The output-input ratio for ten years

[0078] = Estimated value of tobacco leaves produced in ten years / total investment in ten years, used to evaluate investment cost performance. 7. Coal price 1,300 yuan / ton, biomass pellet price 1,000 yuan / ton, tobacco stalk pellet cost 100 yuan / ton (farmers pay four self-help and one fee to process tobacco stalk pellets), electricity price 0.45 yuan / kWh.

[0079] Table 6 Statistics of low fire test

[0080]

[0081] Note: The feed pipe diameter of this test burner is 75mm.

[0082] It can be seen from the above experimental data that the burner head provided by the present invention has good combustion performance, can effectively reduce the cost of use, and has good low fire maintenance capability.

[0083] The above specific examples are used to illustrate the present invention, which is only used to help understand the present invention and is not intended to limit the present invention. For those skilled in the art, according to the concept of the present invention, some simple deductions, modifications or substitutions can be made.

Claims

1. A biomass burning stove head, comprising: A combustion chamber, characterized in that a function distribution plate is provided at one end of the combustion chamber, a feed port, a primary air inlet, a secondary air inlet and a tertiary air inlet are provided on the function distribution plate, a tertiary combustion head is provided on the top of the combustion chamber, and a primary combustion zone, a secondary combustion zone and a tertiary combustion zone are provided inside, the primary combustion zone is located at the feed port, the secondary combustion zone is located below and in front of the primary combustion zone, and the tertiary combustion zone is located at the top of the chamber; A primary combustion-supporting air duct, a secondary combustion-supporting air duct and a tertiary combustion-supporting air duct are arranged in the combustion chamber, the primary air inlet is connected to the primary combustion-supporting air duct, the secondary air inlet is connected to the secondary combustion-supporting air duct, the tertiary air inlet is connected to the tertiary combustion-supporting air duct, the primary combustion-supporting air duct is used to supply air to the primary combustion zone, the secondary combustion-supporting air duct is used to supply air to the secondary combustion zone, and the tertiary combustion-supporting air duct is used to supply air to the tertiary combustion zone; The primary air inlet is located below the feed inlet, the secondary air inlet is located below the primary air inlet, and the tertiary air inlet is located above the feed inlet.

2. The biomass burning stove head according to claim 1, characterized in that: A primary combustion table in the shape of "┐" as a whole is provided at the feed inlet, a primary air inlet hole is provided on the primary combustion table, and the primary combustion-supporting air duct is located below the primary combustion table; a secondary combustion plate is provided directly in front and below the primary combustion table away from the feed inlet, a secondary air inlet hole is provided on the secondary combustion plate, and the secondary combustion-supporting air duct is located below the secondary combustion plate; after the fuel enters the primary combustion table through the feeding pipe, it accumulates and burns on the primary combustion table, and with the continuous supply and accumulation of fuel on the primary combustion table, the fuel that has completed the primary combustion but has not been burned falls onto the secondary combustion plate for secondary combustion after the primary combustion table is filled with fuel and under the thrust of continuous feeding.

3. The biomass burning stove head according to claim 1, characterized in that: The tertiary combustion-supporting air duct is located at the top and around the side walls of the combustion chamber. The combustion-supporting air entering the tertiary combustion-supporting air duct flows along the air duct to the side walls and top of the tertiary combustion head. The side walls and top of the tertiary combustion head are provided with tertiary air inlet holes.

4. The biomass burning stove head according to claim 2, characterized in that: The combustion chamber is provided with an ash and char removal device, and the ash and char removal device comprises: The ash and charcoal outlet is located at the end of the combustion chamber away from the feed inlet; The ash and char removal push plate is located above the secondary combustion plate, fits closely with the secondary combustion plate, and has the same shape as the secondary combustion plate. When the ash and char removal plate moves horizontally on the secondary combustion plate, it shovels in from under the fuel on the secondary combustion plate, and drives the fuel to move toward the ash and charcoal outlet when shoveling; When removing charcoal, the charcoal removing plate moves toward the charcoal outlet end, prompting the bottom charcoal on the secondary combustion plate and the burning fuel to move forward. As the end of the propulsion stroke approaches, the charcoal that was previously stranded at the charcoal outlet will be squeezed out of the combustion chamber. In addition, when the charcoal removing plate starts to move, the charcoal removing plate will push the fuel accumulated at the bottom of the junction of the primary combustion platform and the secondary combustion plate forward. Such a push will cause the fuel at the upper layer of the junction to lose support, sink, and then fall on the charcoal removing plate moving forward and move along with it. When the ash cleaning plate reaches the end of the advancing stroke, the ash cleaning plate will reset. At the beginning of the reset process, the ash that is at the front end of the ash cleaning plate but not on the ash cleaning plate will remain at the ash outlet. When the ash cleaning plate runs to this position next time, it will be extruded in the same way. The ash placed on the ash cleaning plate and the unburned fuel will move backward with the ash cleaning plate and gradually fall on the secondary combustion plate during the backward movement.

5. The biomass burning stove head according to claim 4, characterized in that: An outlet cover plate is provided at the ash outlet. The outlet cover plate is hinged to the combustion cavity and is also connected to the ash cleaning plate. When the ash cleaning plate moves horizontally back and forth, it drives the outlet cover plate to open and close.

6. The biomass burning stove head according to claim 5, characterized in that: The ash outlet cover plate is pushed by two top rods on the left and right. The roots of the two top rods are connected to the ash cleaning plate push rod.

7. The biomass burning stove head according to claim 1, characterized in that: There are two secondary air inlets symmetrically arranged. The primary air inlet and the two secondary air inlets are distributed in a "pin" shape and are separated by the secondary combustion plate. There are three tertiary air inlets, and the three tertiary air inlets are distributed in an "ㄇ" shape on both sides and above the feed inlet.

8. The biomass burning stove head according to claim 2, characterized in that: The secondary air inlet holes are arranged in such a way that the air volume gradually decreases from the end close to the primary combustion table to the end far from the primary combustion table.

9. A biomass burner, characterized in that: It includes a feed bin, a wind gathering bin and the biomass burner head according to any one of claims 1-8. The wind gathering bin is docked with the biomass burner head.

10. The biomass burner according to claim 9, characterized in that: Inside one end of the wind gathering bin close to the biomass burner head, there are a secondary combustion air pneumatic baffle and a tertiary combustion air pneumatic baffle. Both the secondary combustion air pneumatic baffle and the tertiary combustion air pneumatic baffle are configured to automatically open under the action of the combustion air, and the opening degree increases with the increase of the combustion air.

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