A biomass pellet low-temperature hot air furnace

Abstract

The present invention relates to the technical field of hot blast furnace equipment, and provides a biomass pellet low-temperature hot blast furnace, the hot blast furnace comprising: a fuel bin, which is provided with an upper material limit and a lower material limit, and an observation port is provided on the outside, and the material is automatically intermittently discharged by matching the change of the output hot air through the discharge valve on the left; the discharge port is located at the intersection of the bottom of the fuel bin and the combustion chamber at the bottom of the hot blast furnace, and is used to control the fuel to enter the specific position inside the combustion chamber. The present invention minimizes the floor space by means of a built-in fuel bin, and is suitable for the site requirements of different customers without the need for an additional fuel bin; and the valve-type control of discharge prevents fuel accumulation, makes the combustion more complete, prolongs the combustion time and improves the utilization rate; in addition, the combustion products generated by burning wood pellets or rice husk pellets can be effectively removed from the combustion chamber through a chain-type ash discharge structure; finally, the vulnerable parts in the high-temperature zone of the exchanger are small in size and easy to assemble and disassemble, which effectively reduces consumables and saves maintenance costs.

Description

Technical Field

[0001] The present invention relates to the technical field of hot blast furnace equipment, and more specifically, to a biomass particle low-temperature hot blast furnace. Background Art

[0002] Biomass pellet low temperature hot air furnace is a kind of equipment that uses biomass pellets as fuel for energy utilization. It is widely used in the drying of grains, medicinal materials, various agricultural and sideline products and various materials. It can also be used for heating factories and greenhouses. It uses biomass pellets as fuel. The heat generated during combustion passes through the heat exchanger, and the heat exchanger converts the clean cold air into hot air. Compared with traditional coal-fired furnaces, it has the advantages of environmental protection, high efficiency, low cost, and renewable. In the context of the growing social awareness of environmental protection, more and more people are beginning to pay attention to and use biomass pellet furnaces.

[0003] At present, the biomass pellet hot air furnaces produced on the market are large in size and have a fixed internal structure, which makes it easy for pellet fuel to have residues when burning. Incomplete combustion of pellets causes black smoke from the chimney, and the emission of ash will directly accumulate, resulting in coking.

[0004] In order to solve the above problems, the present application proposes a biomass particle low-temperature hot air furnace. Summary of the invention

[0005] The object of the present invention is to provide a biomass particle low-temperature hot blast furnace with a chain-type ash removal design, so that the products of burning any particles can be fully removed from the combustion chamber, the combustion is more complete and the utilization rate is improved.

[0006] To solve the above technical problems, the present invention is achieved through the following technical solutions:

[0007] A biomass particle low-temperature hot air furnace, the hot air furnace comprising:

[0008] The fuel silo is equipped with an upper material limit and a lower material limit inside and an observation port outside. Automatic intermittent material discharge is carried out through the discharge valve on the left and the internal impeller matching the change of the output hot air;

[0009] Through the intermittent feeding method in the above technical solution, the amount of remaining biomass particles in the combustion chamber is controlled, so that the combustion amount is constant, the combustion time of the biomass particles is extended to the greatest extent while meeting the temperature requirements, the utilization rate of the fuel is improved, and the fuel cost is saved while ensuring the performance of the equipment.

[0010] The discharge port is located at the junction of the lower part of the fuel bin and the combustion chamber at the bottom of the hot blast furnace, and is used to control the fuel to enter the specific position inside the combustion chamber through the internal flap;

[0011] By guiding the biomass particles in the above technical solution, the particle fuel can be effectively prevented from agglomerating in the combustion chamber, so that the flame is evenly distributed in the combustion area to improve the heat utilization rate, and the flame range is diffused to the greatest extent while meeting the temperature requirements, avoiding the waste of flame concentration caused by fuel aggregation.

[0012] The ash discharge chain is located below the combustion chamber and is linked to the discharge valve, so that the biomass particles burn above the ash discharge chain to prevent accumulation and coking. At the same time, the ash discharge chain is driven by the built-in chain reducer to remove the ash from the combustion chamber.

[0013] By using the ash discharge chain in the above technical solution to drive the biomass particles to move, the combustion products are sent out in real time during the combustion period, so as to achieve the effect of real-time ash discharge, so that the combustion products of different types of fuel particles can be effectively removed from the combustion chamber, preventing the generated ash from accumulating inside the particle fuel and affecting the combustion effect.

[0014] The exchanger is located near the rear of the hot blast furnace and consists of two groups of exchange tubes. The front group of exchange tubes of the two groups of exchange tubes consists of a long movable tube and a short movable tube to form an upper and lower double-layer structure, which is convenient for replacing vulnerable parts in the high-temperature area;

[0015] By setting the vulnerable parts in a segmented structure with a longer upper part and a shorter lower part in the high-temperature area in the above technical solution, it is only necessary to replace a section (short-distance section) closer to the high-temperature area during maintenance work, thereby effectively reducing the replacement consumables of vulnerable parts, reducing the difficulty of maintenance work and achieving the effect of saving maintenance costs.

[0016] The exchange prefabricated part is located below the exchanger and is cast as a whole by refractory materials. It is in direct contact with the high-temperature open flame. The cold air is isolated outside the exchange tube for heat exchange, so that the hot air finally output is also clean hot air.

[0017] By concentrating the flame inside the exchange tube in the above technical solution, the smoke is also isolated inside, so that the clean cold air remains clean after being heated to hot air outside the exchange tube, which is convenient for use by other spaces and equipment that need to be heated after being discharged.

[0018] Beneficial effects of the present invention:

[0019] The present invention automatically controls the feeding amount of biomass particles according to the change of the output hot air through the feeding valve, so as to achieve the function of intermittent feeding, thereby matching the power of the equipment, preventing the accumulation of biomass particles and increasing the output hot air temperature. In addition, under the condition of the same amount of biomass particles, the combustion quality can be guaranteed and the combustion time can be extended, thereby improving the combustion completeness and heat utilization rate of the biomass particles.

[0020] Through the linkage of the ash discharge chain and the unloading valve, the biomass particles are burned on the chain, and the ashes after combustion are slowly transported to the ash discharge port through the movement of the chain. The solid particles are burned into ashes, which naturally fall on the slag removal auger and are finally discharged out of the furnace in real time. This can ensure the full combustion of the biomass particles and prevent the accumulation and coking of ash residues, thereby ensuring the combustion effect of the subsequent biomass particles. After this arrangement, the combustion products of different types of fuel particles can be effectively removed from the combustion chamber.

[0021] The present invention prevents high-temperature open flames from directly impacting the exchange tubes by making the exchange prefabricated parts integrally cast from refractory materials contact the open flames, and sets the most easily damaged part as a short movable tube, so that the short exchange tubes can be taken out and replaced as a whole after the long exchange tubes are pulled out, without the need to replace the entire exchange tubes, thus saving maintenance costs. At the same time, negative pressure combustion is used to prevent fire spraying from the air supply port and the feed port, thereby ensuring the operational safety of the equipment.

[0022] The exchanger is heated by circulating the flame of the combustion chamber inside the exchange tube, and the cold air that needs to be heated is heat exchanged through the outside of the exchange tube, so that the hot air finally output is also clean hot air. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 It is a schematic diagram of the right cross-section structure of the hot blast stove of the present invention;

[0025] Figure 2 It is a schematic diagram of the three-dimensional structure of the hot blast furnace of the present invention;

[0026] Figure 3 It is a schematic diagram of the three-dimensional structure of the right side of the hot blast stove of the present invention;

[0027] Figure 4 It is a schematic diagram of the front cross-sectional structure of the hot blast furnace of the present invention;

[0028] Figure 5 For the present invention Figure 4 Schematic diagram of the cross-section structure of the middle and lower material valve;

[0029] Figure 6 For the present invention Figure 4 Schematic diagram of the cross-sectional structure of the middle feed port. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Embodiment 1

[0031] See also Figure 1 - Figure 6 The present invention provides a biomass particle low-temperature hot air furnace.

[0032] like Figure 1 - Figure 6 As shown, a guardrail 4 is provided above the hot blast furnace 1, and the interior includes:

[0033] The fuel bin 2 is provided with an upper material limit and a lower material limit inside, and an observation port outside; an impeller 20 is provided in the unloading valve 17 on the left side of the fuel bin 2, which is driven to rotate by the reduction motor on the outside, and an inspection cover 19 and an observation port are provided on the outside of the unloading valve 17, and a plug plate 18 is provided on the top; the biomass particles are stored in the bin above the unloading valve 17 after loading, and the lower part of the unloading valve 17 is connected to the left end of the combustion chamber 3. The biomass particles are transported by rotating the impeller 20 driven by the reduction motor, and automatic intermittent unloading is carried out in accordance with the changes in the output hot air, and a furnace door 14 is provided in front of the combustion chamber 3.

[0034] The discharge port 16 is connected to the combustion chamber 3 below the discharge valve 17. The regulating unit 22 at the bottom of the discharge port 16 is composed of an arc-shaped plate and a nut. A support plate is rotatably installed inside the arc-shaped plate and controlled by the nut. The lower end of the support plate is connected to the flap 21 inside the discharge port 16 to control the placement angle of the flap 21.

[0035] The ash discharge chain 15 is located below the combustion chamber 3 and is linked to the discharge valve 17. After the biomass particles fall, they are burned above the crawler of the ash discharge chain 15 and driven by the internal chain reducer to generate a cyclic rotation motion, so that the biomass particles move outward during the combustion and heat release process.

[0036] In the specific implementation, the biomass particles first enter the fuel bin 2 in the furnace through the elevator, and some of the biomass particles first enter the right bin and arrive at the unloading valve 17. At this time, the reduction motor drives the impeller 20 to rotate according to the change of the hot air output in the furnace, so that the biomass particles pass through the unloading port 16 and are evenly fed into the combustion chamber 3, forming an intermittent unloading operation;

[0037] Furthermore, when the biomass particles pass through the discharge port 16, the adjustment unit 22 cooperates with the flap 21, and the nut is manually tightened to control the placement angle of the flap 21 according to the combustion conditions in the combustion chamber 3, so that the biomass particles fall into the combustion chamber 3 in the form of a parabola and reach the ash discharge chain row 15; driven by the chain row reducer and automatically changing the frequency according to the change of the smoke exhaust fan frequency, the ash discharge chain row 15 moves at different speeds under different combustion conditions; and at this time, the biomass particles are fully burned in the process of being sent out, and after becoming ash, they automatically fall on the slag removal auger with the movement of the ash discharge chain row 15, and are finally discharged from the combustion chamber 3, thereby forming a real-time ash discharge operation to ensure the combustion quality in the furnace, so that the combustion products of different types of fuel particles can be effectively removed from the combustion chamber 3;

[0038] In addition, in this embodiment, when the output hot air temperature in the furnace is lower than a predetermined value, the amount of biomass particles entering the combustion chamber 3 is increased by increasing the operating time of the unloading valve 17 and the impeller 20 or reducing the operating interval time, thereby achieving the purpose of increasing the output hot air temperature. When the output hot air is higher than a predetermined value, the unloading valve 17 reduces the operating time and increases the operating interval time.

[0039] In addition, in the present embodiment, the ash discharge chain row 15 is a crawler-type circulating motion combustion platform, which is driven by a built-in chain row reducer. A built-in slag removal auger is provided below the outlet, which is driven by the built-in slag removal auger reducer to send the ash dropped inside to the outside of the furnace to keep the space in the furnace constant and maintain the combustion quality of the biomass particles; the air supply fan located in the ash discharge chain row 15 is automatically frequency-controlled according to the change of the smoke exhaust fan frequency, and the ash discharge chain row 15 is linked with the unloading valve 17. Embodiment 2

[0040] like Figure 1 - Figure 3 As shown, the hot air stove 1 includes:

[0041] The exchanger 7 is located between the front air guide box 5 and the rear air guide box 6 in the rear area of ​​the hot air stove 1. The front air guide box 5 and the rear air guide box 6 are staggered up and down and are used to transmit cold air for heat exchange;

[0042] The exchanger 7 is composed of a front group exchange tube and a rear group exchange tube, which are connected to the upper flue 11 on the top of the hot blast stove 1. The front group exchange tube is composed of a long movable tube 8 and a short movable tube 9 to form a double-layer structure, which are connected as a whole by plugging; the rear group exchange tube is connected to the exhaust fan through the lower flue 12 and the exhaust pipe at the bottom;

[0043] The exchange preform 13 is located below the exchanger 7 and docked at the outlet of the combustion chamber 3, in the high temperature area, and docked with the short movable tube 9 through the hole on the top.

[0044] The mesh plate in front of the hot blast furnace 1 is the clean cold air inlet. When the clean cold air passes through the front air guide box 5 and the rear air guide box 6, it is slowly heated by the exchanger 7 to become hot air, and finally discharged from the bell mouth 10 at the rear of the hot blast furnace 1.

[0045] In the specific implementation, the flame of the burning biomass particles will directly contact the exchange prefabricated part 13 which is integrally cast from refractory materials, and a high-temperature area will be formed between the long movable tube 8, the short movable tube 9 and the exchange prefabricated part 13. The parts near the center of the high-temperature area are easily damaged parts. Once the tube body is damaged, the long movable tube 8 can be directly pulled up, and then the short movable tube 9 can be taken out for replacement, which greatly shortens the length of the tube body to be replaced, thereby reducing material loss. After this arrangement, there is no need to replace the entire exchange tube, saving maintenance costs.

[0046] In addition, the exhaust fan in this embodiment is operated by frequency conversion control according to the change of the output temperature, so that the biomass particles inside the furnace are burned under negative pressure, which is used to increase the safety of the equipment during operation and prevent the air supply port and the feed port 16 from spraying fire due to blockage of the exchange tube and the flue under positive pressure;

[0047] In addition, in the present embodiment, the flame burning in the combustion chamber 3 heats the exchanger 7 by circulating inside the exchange preform 13 and the long movable tube 8 and the short movable tube 9, and the cold air that needs to be heated is heat exchanged outside the exchange tube (inside the front air guide box 5 and the rear air guide box 6), so that the cold air remains in a clean state when it is finally output, which is convenient for entering the space that needs to be heated.

[0048] It can be understood that the present invention minimizes the footprint by building in the fuel bin 2, and there is no need to make an additional fuel bin 2 separately, which is suitable for the site requirements of different customers; and the hot blast furnace 1 adopts valve-type control to discharge materials, so that the biomass particles enter evenly to prevent accumulation, promote more complete combustion of the biomass particles, and at the same time extend the combustion time of the biomass particles to improve the utilization rate; in addition, through the chain-type ash discharge structure design, whether it is burning wood particles or rice husk particles, the ashes generated can be smoothly discharged through the chain structure; finally, the high-temperature part of the exchanger 7 contacting the combustion chamber 3 adopts a replaceable refractory castable integrally cast to form an exchange prefabricated part 13, and the high-temperature exchange tube adopts an upper and lower segmented design, the longer exchange tube (long movable tube 8) can be pulled out upward, and the shorter exchange tube (short movable tube 9) can be taken out and replaced as a whole, which is convenient for later maintenance, reduces consumables and saves maintenance costs.

[0049] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0050] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A biomass particle low temperature hot air furnace, characterized in that: Hot air furnace includes: The fuel silo is provided with an upper material limit and a lower material limit inside and an observation port outside. A discharge valve is provided on the left side of the fuel silo for intermittent discharge of materials through an internal impeller; The feed port is located at the junction of the lower part of the fuel bin and the combustion chamber at the bottom of the hot blast furnace, and is used to control the specific position of the particle fuel entering the combustion chamber through the internal flap; The ash discharge chain is located below the combustion chamber and is linked to the discharge valve, so that the biomass particles burn above the ash discharge chain, preventing the fuel particles from agglomerating and improving the heat utilization rate. At the same time, the ash discharge chain is driven by the built-in chain reducer to achieve the discharge of ash. The exchanger is located near the rear of the hot blast furnace and consists of two groups of exchange tubes. The front group of exchange tubes of the two groups of exchange tubes consists of a long movable tube and a short movable tube to form an upper and lower double-layer structure, which is convenient for replacing vulnerable parts in the high-temperature area; The exchange prefabricated part is located below the exchanger and is cast entirely of refractory material. It is in direct contact with the high-temperature open flame in the combustion chamber. The cold air is isolated outside the exchange tube for heat exchange, which is used to prevent flue gas from contaminating the cold air and keep it clean for heat exchange and transmission.

2. A biomass particle low-temperature hot air furnace according to claim 1, characterized in that: The side of the discharge valve is provided with an observation port, and the upper part is provided with a plug plate. The impeller is driven to rotate by an external reduction motor to achieve uniform delivery of biomass particles into the combustion chamber.

3. A biomass particle low-temperature hot air furnace according to claim 2, characterized in that: When the output hot air temperature of the impeller is lower than a predetermined value, the impeller is used to increase the operating time to increase the amount of biomass particle fuel entering the combustion chamber, thereby achieving the effect of increasing the output hot air temperature.

4. A biomass particle low-temperature hot air furnace according to claim 1, characterized in that: An adjusting unit is provided on the outer side of the bottom of the discharge port, which is used to control the angle of the flap according to the flame and temperature conditions in the combustion chamber, so that the biomass particles enter the combustion chamber in a parabolic trajectory.

5. The biomass particle low-temperature hot air furnace according to claim 1, characterized in that: The ash discharge chain is a cyclically moving combustion platform, which circulates in a crawler belt manner, and has an external slag removal auger reducer and a supplementary air fan. The supplementary air fan is automatically frequency-controlled according to changes in the frequency of the smoke exhaust fan.

6. The biomass particle low-temperature hot air furnace according to claim 1, characterized in that: The outlet of the ash discharging chain is connected to the slag removing auger below. During the cyclic movement of the ash discharging chain, the combustion products of the biomass particles above automatically fall onto the slag removing auger, so as to achieve the effect of removing the ash from the combustion chamber in real time.

7. The biomass particle low-temperature hot air furnace according to claim 1, characterized in that: The rear group of exchange tubes of the two groups of exchange tubes is connected to the lower flue at the bottom, and the lower flue is connected to the smoke exhaust fan through the smoke exhaust pipe. The smoke exhaust fan is controlled by frequency conversion according to the change of output temperature, so that the biomass particles inside the furnace are burned under negative pressure.

8. A biomass particle low-temperature hot air furnace according to claim 7, characterized in that: The negative pressure combustion is used to increase safety and prevent fire from erupting from the air supply port and the material discharge port due to blockage of the exchange tube and the flue during positive pressure.

9. The biomass particle low-temperature hot air furnace according to claim 1, characterized in that: The exchange tube formed by the combination of the long movable tube and the short movable tube is located in the high temperature area, and the short movable tube is adjacent to the center of the high temperature area. When the upper and lower segmented structure is maintained, the long movable tube is pulled up and the entire short movable tube is taken out for replacement.

10. The biomass particle low-temperature hot air furnace according to claim 1, characterized in that: The mesh plate in front of the hot blast furnace is the clean cold air inlet. The clean cold air is slowly heated into hot air by the flames in the long movable tube and the short movable tube during passing through the front air guide box and the rear air guide box. The heated hot air is transmitted outward through the bell mouth.

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