CN216844655U

CN216844655U - Direct-fired biomass combustion furnace for Stirling engine

Info

Publication number: CN216844655U
Application number: CN202220357351.8U
Authority: CN
Inventors: 李西平
Original assignee: Guizhou Yujia Technology Co ltd
Current assignee: Guizhou Yujia Technology Co ltd
Priority date: 2022-02-22
Filing date: 2022-02-22
Publication date: 2022-06-28
Anticipated expiration: 2032-02-22

Abstract

The utility model discloses a direct-fired biomass combustion furnace for a Stirling engine, which comprises a furnace body, wherein the furnace body is sequentially provided with a furnace chamber and a combustion chamber from top to bottom, and a heat exchanger for heat exchange is arranged in the furnace chamber; a thermal radiation burner which is connected with the heat exchanger and can generate flat flame is arranged in the combustion chamber, an ash containing box is arranged below the thermal radiation burner, a storage bin is arranged on one side of the furnace body and is connected with the thermal radiation burner through a feeding channel, and a fuel conveying mechanism is arranged on the feeding channel; this biomass combustion furnace enables the hot head of engine to insert in the furnace mouth, is equipped with the thermal radiation combustor in the furnace, adopts the mode of direct combustion and air direct injection, and the casing comprises two sets of radiation section of thick bamboo, and the purpose is homogenization flame temperature, utilizes high temperature to burn red radiation section of thick bamboo, turns into radiant heat with convection heat, carries out radiant heating to the engine hot head through radiation section of thick bamboo, still can block the filtration to the granule in the combustion process, makes flame cross the fire for a long time, and the burning is abundant, does benefit to stirling engine and does work stably.

Description

Direct-fired biomass combustion furnace for Stirling engine

Technical Field

The utility model belongs to the technical field of biomass boiler, concretely relates to direct combustion formula biomass combustion furnace for stirling engine.

Background

The biomass burner is a premixed combustion technology which is developed in recent decades and takes a porous medium as a carrier and is based on an enthalpy combustion theory, a heat storage medium is a heat storage ball, an inorganic salt, a metal alloy or a ceramic honeycomb body, and the main working principle of the biomass burner is that the porous medium can form heat radiation much stronger than a gas phase medium after being heated by high-temperature gas, so that the preheating effect on components which do not undergo chemical reaction at the upstream of premixed gas flow is enhanced, the combustion rate is greatly improved, the stability of flame is enhanced, the flame temperature is improved, the lean combustion is greatly improved, and the emission of harmful pollutants is reduced.

The existing biomass burner mainly uses a combustion boiler and hot water, and only focuses on a certain single heat transfer mode, namely: a hot-boiler mode, a heating mode and a hot-hot water mode, and a biomass burner is not combined with the power generation of a Stirling engine; through the combination of the biomass burner and the Stirling engine, the following problems are mainly solved:

1. the heat efficiency is not high, the generated heat is not high in heat dissipation and heat energy density, and the heat can be directly applied to the engine, so that the engine is easily damaged;

2. the heat generated in the furnace chamber is not uniform, and is generally dragged by a draught fan, under the condition, the temperature of the rear end is higher than that of the front end, because the heat cannot be effectively dissipated, the temperature of the front end is lower, and because the temperature is close to the hot head of the engine, the phenomenon of inconsistent temperature easily generates unstable influence on the working state of the engine;

3. in the combustion process of the biomass combustion furnace, when the temperature reaches over 1000 ℃, coking is easy to generate, the heat absorption of a hot head of an engine is influenced, and the coking is adhered to a capillary tube of the hot head, so that the service life of the biomass combustion furnace is influenced.

Disclosure of Invention

In view of this, the present invention provides a direct-fired biomass combustion furnace for stirling engine, which has high heating efficiency, good heating stability and can increase the effective heating area.

The technical scheme of the utility model is that:

a direct-fired biomass combustion furnace for a Stirling engine comprises a furnace body, wherein a hearth and a combustion chamber are sequentially arranged in the furnace body from top to bottom, and a heat exchanger for heat exchange is arranged in the hearth; be equipped with the thermal radiation combustor that can produce flat flame of being connected with the heat exchanger in the combustion chamber, thermal radiation combustor below is equipped with dress ash box, is equipped with the feed bin in furnace body one side, and the feed bin passes through feedstock channel and is connected with thermal radiation combustor, is equipped with fuel conveying mechanism on feedstock channel.

The thermal radiation burner comprises a shell, a burner chamber is arranged in the shell, a thermal radiation cylinder capable of uniformly conveying fuel gas is arranged at the top in a combustion chamber, and a radiation plate opposite to the thermal radiation cylinder is arranged at the outer top end.

The bottom of the hearth is provided with a bracket communicated with the hearth, the top of the hearth is provided with a smoke exhaust chamber, one end of the hearth is uniformly provided with a plurality of gas inlets and air inlets, and the heat radiation cylinder is provided with a plurality of gas outlets corresponding to the gas inlets so as to be connected with the gas inlets through gas pipes; the radiation plate is arranged in the smoke exhaust chamber, a smoke exhaust hole communicated with the device chamber is arranged on the radiation plate, a smoke outlet cavity channel is arranged in the bracket, a plurality of smoke exhaust ports are uniformly distributed on the outer side surface of the smoke exhaust chamber, and the smoke exhaust ports are connected with the smoke outlet cavity channel through a return air pipe.

The heat radiation cylinder is of a double-layer cylindrical structure, the two layers of cylinders are connected through a plurality of slender circular tubes which enable the two layers of cylinders to be mutually communicated, and the gas outlet end of the gas tube extends into the outer layer of cylinder; a plurality of small filtering holes are formed in the surface of the outer-layer cylinder, an opening is formed in the top end of the outer-layer cylinder, and the radiation plate is arranged at the opening of the outer-layer cylinder.

The radiation plate is a circular ring radiation plate, the shaft hole of the circular ring radiation plate is matched with the opening of the outer-layer cylinder, and at least four smoke exhaust holes are circumferentially distributed on the circular ring radiation plate.

The heat radiation burner is provided with at least 8 gas inlets circumferentially and uniformly distributed on the hearth, at least 6 air inlets circumferentially and uniformly distributed between every two gas inlets, and at least 12 air return pipes.

The heat radiation burner bracket is provided with an air inducing port, and a cold water inlet and a hot water outlet are symmetrically arranged on the furnace body of the burner.

The outer side wall of the heat exchanger is provided with a smoke outlet, and a chimney or a draught fan is arranged on the smoke outlet.

The lower end of the thermal radiation burner is hinged with a grate connected with the feeding channel through a hinge shaft, the fuel conveying mechanism comprises a gear arranged on the hinge shaft, a motor is arranged on one side of the grate, and the gear is connected with the motor through a chain.

An ash discharge port is formed in one side of the thermal radiation combustor, and a baffle is arranged at the ash discharge port.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model comprises a furnace body, wherein a furnace chamber and a combustion chamber are arranged in the furnace body from top to bottom in sequence, and a heat exchanger for heat exchange is arranged in the furnace chamber; a thermal radiation burner which is connected with the heat exchanger and can generate flat flame is arranged in the combustion chamber, an ash containing box is arranged below the thermal radiation burner, a storage bin is arranged on one side of the furnace body and is connected with the thermal radiation burner through a feeding channel, and a fuel conveying mechanism is arranged on the feeding channel; the heat radiation combustor comprises a shell, a combustor is arranged in the shell, a double-layer tubular heat radiation cylinder capable of uniformly conveying gas is arranged at the top in a combustion chamber, a circular ring radiation plate opposite to the heat radiation cylinder is arranged at the outer top end of the double-layer tubular heat radiation cylinder, the combustor is arranged in the shell, a plurality of gas inlets and air inlets are uniformly distributed at one end of the combustor, a plurality of gas outlets corresponding to the gas inlets are formed in the heat radiation cylinder, and the heat radiation cylinder is connected with the gas inlets through gas pipes; the radiation plate is arranged on one side of the smoke exhaust chamber, a smoke exhaust hole communicated with the device chamber is arranged on the radiation plate, a smoke outlet channel is arranged in the bracket, a plurality of smoke exhaust ports are uniformly distributed on the outer side surface of the smoke exhaust chamber, and the smoke exhaust ports are connected with the smoke outlet channel through a return air pipe.

The combustor with the functions of absorbing heat, gathering heat, flowing speed and the like is added in the biomass combustion furnace, heat energy is absorbed and transferred uniformly through the combustor, the main mode of heating a Stirling engine thermal head is provided, the combustor is adopted, smoothness of gas is ensured, uniformity of temperature is realized, two layers of radiation barrels and an air inlet channel are adopted, and the combustor adopts a special structural design to achieve the purpose of generating flat flame.

Through adding the burner, the biomass combustion flame enters through the flue gas and the air through respective pipelines, combustion supporting is achieved by mixing in the furnace body, heat generated by combustion reaches the heat head of the Stirling engine through the modes of convection heat transfer and radiation heat transfer, the heat is absorbed by the heat head to ensure the normal work of the Stirling engine, 8 fuel gas inlets are uniformly distributed through changing the number of the air inlets, the fuel gas inlets and the air return pipes of the biomass burner, 6 air inlets are uniformly distributed around each fuel gas inlet, cooling air seals off the flame through radial wind, uniform plane flame is formed in a combustion area, and a uniformly distributed stable field meets the requirements of the temperature of a hearth and the work of an engine; the utility model solves the problem of temperature uniformity of the biomass combustion furnace, ensures the flame uniformity of the high-quality flat flame burner, and inhibits the high-point temperature rise by utilizing the homogenization effect of the radiation cylinder; the turbulence of the radiation cylinder is utilized to improve the flame uniformity, and the concentration of nitrogen oxide NOX pollutants of the gas burner is lower than that specified by the national standard, thus meeting the national requirement of environmental protection.

Drawings

FIG. 1 is a schematic structural view of a biomass combustion furnace according to the present invention;

fig. 2 is a perspective view of the heat radiation burner of the present invention;

fig. 3 is a perspective view of the heat radiation burner of the present invention;

fig. 4 is a top view of the heat radiation burner of the present invention;

fig. 5 is a plan view of the heat radiation burner of the present invention;

fig. 6 is a side view of the heat radiation burner of the present invention;

fig. 7 is a side view of the heat radiation burner of the present invention;

fig. 8 is a sectional view of the heat radiation burner of the present invention;

fig. 9 is a perspective half-sectional view of the heat radiation burner of the present invention.

In the figure: 1-furnace body; 2-a heat exchanger; 3-a heat radiation burner; 3-1-induced draft; 3-2-cold water inlet; 3-3-hot water outlet; 3-4-water outlet; 31-a housing; 32-machine chamber; 32-1-smoke exhaust chamber; 33-a scaffold; 34-a gas inlet; 35-air inlet; 36-a thermal radiation cartridge; 36-1-outer layer cylinder; 37-a gas pipe; 38-a radiation plate; 39-air return pipe; 4-ash containing box; 5, a motor; 6-a chain; 7-a grate; 8-a storage bin; 9-a feed channel; 10-communicating tube; 11-elongated hollow round tube.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.

As shown in fig. 1, a direct-fired biomass combustion furnace for a stirling engine comprises a furnace body 1, wherein a hearth and a combustion chamber are sequentially arranged in the furnace body 1 from top to bottom, and a heat exchanger 2 for heat exchange is arranged in the hearth; be equipped with the thermal radiation combustor 3 that can produce flat flame who is connected with heat exchanger 2 in the combustion chamber, thermal radiation combustor 3 below is equipped with dress ash box 4, is equipped with feed bin 8 in furnace body 1 one side, and feed bin 8 passes through feedstock channel 9 to be connected with thermal radiation combustor 3, is equipped with fuel conveying mechanism on feedstock channel 9.

The fuel conveying mechanism comprises a hinge shaft arranged on a grate 7 at the lower end of the thermal radiation burner 3, a gear is arranged on the hinge shaft, a motor 5 is arranged on one side of the grate 7, and the gear is mutually connected with the motor 5 through a chain 6; one end of the hearth and the combustion chamber is provided with a bin 8, the bin 8 is communicated with a feeding channel 9 of the thermal radiation combustor 3, and the left end of the bin is provided with an ash discharge port and a baffle; the motor 5 drives the grate 7 to rotate, so that the combustion materials enter the combustion chamber from the feeding pipe in a following feeding mode, are gasified and volatilized to be combusted in the combustion chamber, and the obtained high-temperature airflow enters the heat exchanger 2 to exchange heat and then discharge waste gas; the rotation of the grate 7 also enables the burnt ash to be discharged from the ash discharge port at the left end of the grate and fall into the ash containing box 4, thereby realizing the automation of charging and discharging ash; the outer side wall of the heat exchanger 2 is provided with a smoke outlet, and a chimney or a draught fan can be arranged on the smoke outlet.

Biomass fuel carries out direct combustion in furnace bottom, has solved smokeless dirt and tar when burning, and fuel can the complete combustion, and the burning residue is few. The primary air and the secondary air distribution system in the combustor are separated, the primary air is mainly provided by the feed inlet by utilizing the chimney draft, the direct combustion of the biomass fuel is completed, the heated secondary air is supplied, the full mixing combustion of combustible gas and air at the combustor is promoted, and the combustion efficiency is further improved.

The utility model discloses a design power 25KW, the hot conversion efficiency 33% of engine calculate according to stirling, the power of actual input hot junction should not be less than 85KW, promptly when the thermal efficiency is 100%, heater output is not less than 85KW, consider heat loss, factors such as heat loss, biomass combustion furnace according to 100KW calculates, need the burning furnace that fires of a 10 ten thousand-12 ten thousand big cards, come as stirling's heat source machine, its concrete performance index is:

1. the gas combustion hot end, namely the temperature of a heat exchange position is 800-1100 ℃, the temperature is adjustable, and the temperature unevenness of a heat exchange surface is less than 10%;

2. the heating furnace outputs 100-120 KW of thermal power;

3. opening reserved cold air in the early stage, and enabling the exhaust temperature of tail gas to be not more than 100 ℃;

4. the generated power of the engine is ensured to reach 25 KW.

According to the requirements of the actual size and heating power of the Stirling engine thermal head and the combination of the actual working environment, the key component materials and the approximate shape of the heating furnace are selected, and the structural design of the combustor 3 in the biomass combustion furnace is preliminarily completed.

As shown in fig. 2-7, the thermal radiation burner 3 includes a housing 31, a chamber 32 is provided in the housing 31, a thermal radiation tube 36 capable of uniformly delivering gas is provided at the top of the combustion chamber, a radiation plate 38 opposite to the thermal radiation tube 36 is provided at the outer top end, an annular support 33 communicated with the chamber 32 is provided at the bottom of the chamber 32, a smoke exhaust chamber 32-1 is provided at the top, and the smoke exhaust chamber 32-1 is communicated with the chamber 32 through a communication pipe 10; a plurality of gas inlets 34 and air inlets 35 are uniformly distributed at one end of the chamber 32, and a plurality of gas outlets corresponding to the gas inlets 34 are arranged on the heat radiation cylinder 36, so that the heat radiation cylinder 36 is connected with the gas inlets 34 through gas pipes 37; the radiation plate 38 is arranged at one side of the smoke discharging chamber 32-1, a smoke discharging hole communicated with the device chamber 32 is arranged on the radiation plate, a smoke discharging cavity channel is arranged in the bracket 33, a plurality of smoke discharging ports are uniformly distributed at the outer side surface of the smoke discharging chamber 32-1, and the smoke discharging ports are connected with the smoke discharging cavity channel through a return air pipe 38.

As shown in fig. 8-9, the heat radiation cylinder 36 is a double-layer cylinder structure, the two cylinders are connected by a plurality of slender hollow circular tubes 11 which enable the two cylinders to be mutually communicated, and the gas outlet end of the gas tube 37 extends into the outer cylinder 36-1; the surface of the outer layer cylinder 36-1 is provided with a plurality of small holes capable of filtering combustion particles, the top end of the outer layer cylinder is provided with an opening, and the radiation plate 38 is arranged at the opening of the outer layer cylinder 36-1.

The radiation plate 38 is a circular ring radiation plate, the shaft hole of the circular ring radiation plate is matched with the opening of the outer layer cylinder 36-1, and at least four smoke exhaust holes are circumferentially distributed on the circular ring radiation plate 38.

At least 8 gas inlets 34 are uniformly distributed on the circumference of the chamber of the thermal radiation burner 3, 6 air inlets 35 are uniformly distributed on the circumference between every two gas inlets 34, so that the cooling air blocks the flame through radial wind, a long straight flame is not formed, a uniform plane flame is formed in a combustion area, at least 12 air return pipes 39 are provided, the fluid in the furnace body is uniformly distributed, the requirements of heating temperature and the working condition of a Stirling engine are met, and the requirement of uniformity of temperature field distribution is met; form annular flame through utilizing air and gas pipeline setting, chooseed porous structure's flat flame combustor for use, this combustor can provide even face-like flame, 8 equipartition gas inlets 34, 6 equipartition air intlet 35 around every gas inlet 34, and gas and air are penetrated directly in the ware thorax, are mixed the postcombustion in the ware thorax. The flow field inside the furnace is regulated by changing the number of gas inlets 34 and air inlets 35 of the burner 3, the position and number of the air return pipes 38, and adding the radiation cylinders 36, etc. Through the addition of the combustor, biomass combustion flame enters through the flue gas and air through respective pipelines, combustion is supported in the shell in a mixed mode, heat generated by combustion reaches the heat head of the Stirling engine through a convection heat transfer mode and a radiation heat transfer mode, and the heat is absorbed through the heat head so as to ensure the normal work of the Stirling engine.

An induced air port 3-1 is arranged on a bracket 33 of the thermal radiation burner 3, water outlets 3-4 are also arranged between gas inlets 34 on the bottom surface of the bracket 33, the number of the water outlets 3-4 is at least two, and a cold water inlet 3-2 and a hot water outlet 3-3 are symmetrically arranged on a furnace body of the burner 3.

To further improve combustion efficiency. The shell area is provided with two radiation cylinders, the purpose is to further homogenize the flame temperature, and the purpose is to convert convection heat into radiation heat by using a high-temperature red-burning radiation cylinder, so that the heat end is heated by the radiation cylinders, and the effective heating area is increased; the high-temperature tail gas is led back to the heat exchanger by the reflux zone, and the heat exchange area of cold and hot air is increased by the heat exchange zone, so that the energy recovery is completed.

The number of the air inlet 35, the gas inlet 34 and the gas return pipe 39 of the biomass burner is changed, the heat radiation burner 3 is subjected to multiple experiments, high-temperature heat pipe conduction is added, an optimal structure and parameters are obtained, the obtained optimal structure is analyzed, and the temperature uniformity and other characteristics of the inner cavity burner of the biomass combustion furnace are completed by analyzing an internal flow field, a temperature field, the distribution concentration of nitrogen oxide NOX and the like. After the high-temperature heat pipe is added, the heating furnace can burn sufficiently, and only the outer flame part of the heating furnace has a high-temperature area of a small area. The temperature of the gas flowing through the high-temperature heat pipe is uniformly distributed, the flame is obviously homogenized, and the temperature gradient is obviously eliminated. The temperature of the center of the heating furnace is concentrated in a green temperature area, the maximum temperature is 1340 ℃, the minimum temperature is 1280 ℃, the difference is 60 ℃, and the working condition that the temperature difference of the Stirling thermal head is not more than 10 percent is achieved.

The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best understand and utilize the invention.

Claims

1. A direct-fired biomass combustion furnace for a Stirling engine, comprising a furnace body (1), characterized in that: a hearth and a combustion chamber are sequentially arranged in the furnace body (1) from top to bottom, and a heat exchanger (2) for heat exchange is arranged in the hearth; be equipped with in the combustion chamber and produce heat radiation combustor (3) of flat flame with the ability of being connected of heat exchanger (2), heat radiation combustor (3) below is equipped with dress ash box (4), is equipped with feed bin (8) in furnace body (1) one side, and feed bin (8) are connected with heat radiation combustor (3) through feedstock channel (9), are equipped with fuel conveying mechanism on feedstock channel (9).

2. A direct combustion biomass burner for a stirling engine in accordance with claim 1 wherein: the heat radiation burner (3) comprises a shell (31), a burner chamber (32) is arranged in the shell (31), a heat radiation cylinder (36) capable of uniformly conveying fuel gas is arranged at the top in the combustion chamber, and a radiation plate (38) opposite to the heat radiation cylinder (36) is arranged at the outer top end.

3. A direct combustion biomass burner for a stirling engine in accordance with claim 2 wherein: the bottom of the device chamber (32) is provided with a support (33) communicated with the device chamber (32), the top of the device chamber is provided with a smoke exhaust chamber (32-1), one end of the device chamber (32) is uniformly provided with a plurality of gas inlets (34) and air inlets (35), and the heat radiation cylinder (36) is provided with a plurality of gas outlets corresponding to the gas inlets (34), so that the heat radiation cylinder (36) is connected with the gas inlets (34) through gas pipes (37); the radiation plate (38) is arranged in the smoke exhaust chamber (32-1), a smoke exhaust hole communicated with the device chamber (32) is formed in the radiation plate, a smoke outlet channel is formed in the support (33), a plurality of smoke exhaust ports are uniformly distributed on the outer side surface of the smoke exhaust chamber (32-1), and the smoke exhaust ports are connected with the smoke outlet channel through a return air pipe (39).

4. A direct combustion biomass burner for a stirling engine in accordance with claim 3 wherein: the heat radiation cylinder (36) is of a double-layer cylindrical structure, the two layers of cylinders are connected through a plurality of slender circular tubes which enable the two layers of cylinders to be mutually communicated, and the gas outlet end of the gas pipe (37) extends into the outer layer cylinder (36-1); a plurality of small filtering holes are formed in the surface of the outer layer cylinder (36-1), an opening is formed in the top end of the outer layer cylinder, and the radiation plate (38) is arranged at the opening of the outer layer cylinder (36-1).

5. A direct combustion biomass burner for a stirling engine in accordance with claim 3 wherein: the radiant panel (38) is a circular ring radiant panel, the shaft hole of the circular ring radiant panel is matched with the opening of the outer layer cylinder (36-1), and at least four smoke exhaust holes are circumferentially distributed on the circular ring radiant panel (38).

6. A direct combustion biomass burner for a stirling engine in accordance with claim 3 wherein: the heat radiation combustor (3) chamber on be the circumference equipartition and be equipped with 8 at least gas inlets (34), be the circumference equipartition between every gas inlet (34) and be equipped with 6 at least air intlet (35), muffler (39) are 12 at least.

7. A direct combustion biomass burner for a stirling engine as in any one of claims 3 to 6 wherein: the support of the thermal radiation burner (3) is provided with an air induction port (3-1), and a furnace body of the burner (3) is symmetrically provided with a cold water inlet (3-2) and a hot water outlet (3-3).

8. A direct combustion biomass burner for a stirling engine in accordance with claim 1 wherein: a smoke outlet is arranged on the outer side wall of the heat exchanger (2), and a chimney or a draught fan is arranged on the smoke outlet.

9. A direct combustion biomass burner for a stirling engine in accordance with claim 1 wherein: the lower end of the thermal radiation burner (3) is hinged with a grate (7) connected with a feeding channel (9) through a hinge shaft, the fuel conveying mechanism comprises a gear arranged on the hinge shaft, a motor (5) is arranged on one side of the grate (7), and the gear is connected with the motor (5) through a chain (6).

10. A direct combustion biomass burner for a stirling engine in accordance with claim 1 wherein: one side of the thermal radiation burner (3) is provided with an ash discharge port, and a baffle is arranged at the ash discharge port.