CN217635587U - Straw combustion furnace - Google Patents

Abstract

The utility model provides a straw fires burning furnace, including first furnace body, second furnace body and enclosure: the first furnace body is provided with a preheating part; the second furnace body is communicated with the first furnace body along the conveying direction of fuel, the second furnace body comprises a combustion part and a burnout part which are arranged along the conveying direction, a feed inlet is formed in the front end of the first furnace body, and the tail end of the second furnace body is closed; the smoke exhaust hood is arranged outside the second furnace body and provided with a smoke exhaust channel arranged along the conveying direction, the air inlet end of the smoke exhaust channel is communicated with the preheating part, and the air outlet end of the smoke exhaust channel discharges smoke outwards. The utility model provides a straw fires burning furnace aims at realizing tying the abundant drying to the straw, reduces the fume emission temperature, avoids causing the atmosphere pollution.

Description

Straw combustion furnace

Technical Field

The utility model belongs to the technical field of biomass boiler, more specifically say, relate to a straw fires burning furnace.

Background

The straw combustion furnace is divided into a straw bundle combustion furnace, a straw bulk combustion furnace and a straw formed fuel furnace according to different charging forms of straws, and the density of the straws is different due to the different charging forms of the straws, so that the heat value and the required air quantity during combustion are different, and the furnace type designs of the three furnaces are completely different.

The existing straw combustion furnace uses mechanical grates (such as chain grates, reciprocating grates, rocking grates and the like) as primary combustion air distribution equipment, and heat required by drying and preheating straw bundles is obtained by means of heat radiation. Therefore, the fuel humidity of the current straw combustion furnace design is not more than 20%, the fuel heat value is not less than 3000 kcal/kg, and the highest combustible fuel humidity is 30% when the fuel is operated under the design load. Because the humidity of the straws is 40% and the heat value is about 2000 Kcal/kg when the straws are bundled, the existing straw combustion furnace can not directly combust the straws with high humidity and low heat value, otherwise, the straws can not be fully dried, and the load strength of one-time combustion can not be ensured.

In addition, flue gas generated by the existing straw combustion furnace is directly discharged to the atmosphere, and high-temperature flue gas easily pollutes the atmosphere, so that the temperature is increased.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a straw fires burning furnace aims at realizing tying the straw fully dry, reduces the fume emission temperature, avoids causing the atmosphere pollution.

In order to achieve the purpose, the utility model adopts the technical proposal that: provides a straw combustion furnace, which comprises a first furnace body, a second furnace body and a smoke exhaust hood, wherein,

the first furnace body forms a preheating part; the second furnace body is communicated with the first furnace body along the conveying direction of fuel, the second furnace body comprises a combustion part and a burnout part which are arranged along the conveying direction, a feed inlet is formed in the front end of the first furnace body, and the tail end of the second furnace body is closed; the smoke exhaust hood is arranged outside the second furnace body and provided with a smoke exhaust channel arranged along the conveying direction, the air inlet end of the smoke exhaust channel is communicated with the preheating part, and the air outlet end of the smoke exhaust channel discharges smoke outwards.

In a possible implementation manner, the smoke exhaust hood is arranged above the second furnace body, and the smoke exhaust channel is positioned above the second furnace body.

In one possible implementation, the straw combustion furnace further includes:

the cooling hood is arranged outside the smoke exhaust hood, a closed cooling space is formed between the cooling hood and the smoke exhaust hood, and the cooling space is used for filling a cooling medium;

the connecting cover is arranged at the rear end of the smoke exhaust cover, and the connecting cover forms a return cavity with an air inlet end communicated with the smoke exhaust channel; and

the air guide mechanism is arranged in the cooling space, the air inlet end of the air guide mechanism is communicated with the air outlet end of the turn-back cavity, and the air outlet end of the air guide mechanism is used for discharging smoke.

In a possible implementation manner, a heat insulation space is arranged between the cooling hood and the smoke exhaust hood, a support plate is arranged in the heat insulation space, and the support plate is respectively connected with the cooling hood and the smoke exhaust hood.

In a possible implementation manner, the air guide mechanism includes a first air guide tube and a second air guide tube arranged in the up-down direction, an air inlet end of the first air guide tube is communicated with the turn-back cavity, the connecting hood is located in the cooling hood, and the straw combustion furnace further includes:

the air guide cover is positioned at the upstream of the air guide mechanism, an air guide chamber is arranged in the air guide cover, and the air outlet end of the first air guide pipe and the air inlet end of the second air guide pipe are communicated with the air guide chamber respectively.

In a possible implementation mode, the air guide cover is provided with a cleaning opening, the cleaning opening is provided with a cleaning door, and the cleaning door has a closing state for shielding the cleaning opening and an opening state for communicating the cleaning opening with the outside.

In a possible implementation mode, the second furnace body further comprises a slag storage part located on the downstream of the burnout part, a slag discharge port is formed in the bottom of the slag storage part, and a cover plate is covered on the slag discharge port in a sealing mode.

In a possible implementation manner, the straw combustion furnace further comprises a first air blowing assembly arranged at the lower part of the second furnace body, wherein the first air blowing assembly comprises a plurality of first air nozzles arranged along the conveying direction, and the first air nozzles are communicated with the second furnace body and used for conveying air into the second furnace body.

In a possible implementation manner, the first air blowing assemblies are provided in two groups, and the two groups of first air blowing assemblies are symmetrically arranged by taking the axis of the second furnace body as a symmetry axis.

In a possible implementation manner, the straw combustion furnace further includes a second air blowing assembly disposed at an upper portion of the second furnace body in the conveying direction, the second air blowing assembly is communicated with the combustion portion, the second air blowing assembly includes a plurality of second air nozzles distributed along a circumferential direction of the second furnace body, and the second air nozzles are used for introducing air into the combustion portion.

The utility model provides a straw fires burning furnace's beneficial effect lies in: compared with the prior art, the utility model discloses the straw fires burning furnace and seals at the tail end of second furnace body, sets up the feed inlet at the front end of first furnace body and makes preheating part and outside intercommunication, and the burning makes the atmospheric pressure in first furnace body and the second furnace body be higher than outside atmospheric pressure, and consequently the flue gas in first furnace body and the second furnace body can only flow to the feed inlet to make the temperature rise in the preheating part. The heat radiation of high temperature flue gas and burning is simultaneously to the straw bundle heating, accelerates to the drying of straw bundle, reduces the humidity of straw bundle, ensures the load of once burning. After flowing to the preheating part, the high-temperature flue gas enters the smoke exhaust channel, flows along the smoke exhaust channel and is exhausted outwards. The flue gas flows along the smoke exhaust channel, so that the residence time of the flue gas in the straw bundle direct-fired furnace is prolonged, the flue gas is naturally cooled, and the pollution to the atmosphere caused by directly discharging high-temperature flue gas is avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a sectional view of a straw combustion furnace provided in an embodiment of the present invention;

FIG. 2 is a schematic structural view of a straw combustion furnace provided in an embodiment of the present invention;

FIG. 3 is a schematic structural view of a straw combustion furnace provided in an embodiment of the present invention;

fig. 4 is a schematic structural view of a straw combustion furnace provided in the second embodiment of the present invention.

In the figure: 1. a first furnace body; 101. a preheating section; 102. a feed inlet; 2. a second furnace body; 201. a combustion section; 202. a burnout section; 203. a slag storage part; 2031. a slag discharge port; 204. a second slag removal port; 3. a grate; 4. a first tuyere; 5. a connecting cover; 501. a reentry chamber; 6. a cooling jacket; 601. a housing; 602. an end cap; 7. a first air duct; 8. a second airway tube; 9. a gas guide hood; 901. a gas conducting chamber; 10. an explosion-proof tube; 11. a support plate; 12. a smoke exhaust hood; 1201. a smoke evacuation channel; 13. and a second tuyere.

Detailed Description

In order to make the technical problem, technical solution and advantageous effects to be solved by the present invention more clearly understood, the following description is given in conjunction with the accompanying drawings and embodiments to illustrate the present invention in further detail. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1 and fig. 2 together, the straw combustion furnace provided by the present invention will now be described. Straw fires burning furnace, including first furnace body 1, second furnace body 2 and enclosure 12: the first furnace body 1 has a preheating section 101; the second furnace body 2 is communicated with the first furnace body 1 along the conveying direction of the fuel, the second furnace body 2 comprises a combustion part 201 and a burnout part 202 which are arranged along the conveying direction, the front end of the first furnace body 1 is provided with a feed inlet 102, and the tail end of the second furnace body 2 is closed; the fume hood 12 is arranged outside the second furnace body 2, the fume hood 12 is provided with a fume exhaust channel 1201 arranged along the conveying direction, the air inlet end of the fume exhaust channel 1201 is communicated with the preheating part 101, and the air outlet end discharges fume outwards.

The straws are fed into the preheating part 101 from the feeding hole 102 for preheating, and as more straw bundles are gradually pushed into the preheating part 101, the straw bundles which enter the preheating part 101 first can gradually move to the rear part along with the pushing of the subsequent straw bundles, the straw bundles are combusted in the combustion part 201 to release heat and gradually become ash, and then the ash is pushed into the burnout part 202 by the subsequent heat-released straw bundles to continue to combust.

The utility model provides a straw fires burning furnace, compared with the prior art, the utility model discloses the straw fires burning furnace seals at the tail end of second furnace body 2, sets up feed inlet 102 at the front end of first furnace body 1 and makes preheating part 101 and outside intercommunication, and the burning makes the atmospheric pressure in first furnace body 1 and the second furnace body 2 be higher than outside atmospheric pressure, and consequently the flue gas in first furnace body 1 and the second furnace body 2 can only flow to feed inlet 102 to make the temperature rise in the preheating part 101. The high-temperature flue gas and the heat radiation of combustion heat the straw bundle simultaneously, and the drying to the straw bundle is accelerated, reduces the humidity of straw bundle, ensures the load of once burning. After flowing to the preheating section 101, the high-temperature flue gas enters the flue gas exhaust passage 1201, flows along the flue gas exhaust passage 1201, and is discharged to the outside. The smoke flows along the smoke exhaust channel 1201, so that the retention time of the smoke in the straw bundle direct-fired furnace is prolonged, the smoke is naturally cooled, and the pollution to the atmosphere caused by the direct discharge of high-temperature smoke is avoided.

It should be noted that, in the existing straw combustion furnace, an inlet is usually arranged at the front end along the fuel conveying direction, an outlet is arranged at the rear end, and straw bundles enter from the inlet and then sequentially move to the outlet along the hearth, and are discharged from the outlet. Therefore, the flue gas of the existing straw combustion furnace flows from the inlet to the outlet, the heat of the preheating zone is only radiated by heat, the drying effect is poor, and the combustion load is influenced.

The terms "front" and "rear" refer to the orientation in the fuel transport direction.

Optionally, the first furnace body 1 and the second furnace body 2 may be an integral component or may be separate components.

Optionally, the feed inlet 102 is disposed at the lower part of the front end of the first furnace body 1, and because the high-temperature flue gas flows upwards, the feed inlet 102 disposed at the lower part of the first furnace body 1 can reduce the probability of discharging the flue gas from the feed inlet 102.

Optionally, a vent hole is formed in the front end of the first furnace body 1, high-pressure air is introduced into the preheating portion 101 through the vent hole, the flow direction of the high-pressure air is consistent with the conveying direction of the straw bundles, and the combustion of the straw bundles can be accelerated. In addition, the high-pressure air entering the preheating part 101 can accelerate the evaporation of the moisture on the surface of the straw bundle, and further dry the straw bundle.

Optionally, a second slag removal port 204 is formed in the second furnace body 2, the second slag removal port 204 can clean ash in the combustion portion 201 and the burnout portion 202, and meanwhile, the combustion condition of the straw bundle can be conveniently observed, and the combustion fault can be timely processed.

Optionally, the second furnace body 2 includes a cylinder and a sealing plate covering the end of the cylinder, and the cylinder and the sealing plate may be an integral component or a separate component.

In some embodiments, referring to fig. 1 and 2, the fume hood 12 is disposed above the second furnace body 2, and the fume exhaust channel 1201 is located above the second furnace body 2.

Because of the upward emission of high temperature flue gas, set up exhaust passage 1201 in the top of second furnace body 2 and be favorable to the flue gas to get into exhaust passage 1201, in time discharge the flue gas in the furnace.

Optionally, the number of the smoke exhaust channels 1201 is two, the two smoke exhaust channels 1201 are symmetrically arranged along the axis of the second furnace body 2, the smoke exhaust speed of the smoke exhaust channels 1201 is increased, and the straw bundles can be combusted by enough air in the hearth.

In some embodiments, referring to fig. 1 to 4, the straw combustion furnace further includes a cooling hood 6, a connecting hood 5, and an air guide mechanism, the cooling hood 6 is disposed outside the smoke exhaust hood 12, a closed cooling space is formed between the cooling hood 6 and the smoke exhaust hood 12, and the cooling space is used for filling a cooling medium; the connecting hood 5 is arranged at the rear end of the smoke exhaust hood 12, and the connecting hood 5 forms a return cavity 501 of an air inlet end and a smoke exhaust channel 1201; the air guide mechanism is arranged in the cooling space, the air inlet end of the air guide mechanism is communicated with the air outlet end of the turn-back cavity 501, and the air outlet end of the air guide mechanism is used for discharging flue gas.

In this embodiment, after the flue gas is discharged from the smoke discharge channel 1201, the flue gas enters the turn-back cavity 501, then enters the gas guide mechanism from the turn-back cavity 501, and is discharged from the gas outlet end of the gas guide mechanism. The flue gas exchanges heat with the cooling medium in the gas guide mechanism, so that the temperature of the flue gas is reduced, and the atmospheric pollution caused by the discharge of high-temperature flue gas is avoided.

Alternatively, the axis of the first airway tube 7 is parallel to the direction of delivery.

Alternatively, the cooling medium may be water, oil or salt.

In some embodiments, referring to fig. 1 to 4, a heat insulation space is provided between the cooling hood 6 and the smoke exhaust hood 12, a support plate 11 is provided in the heat insulation space, and the support plate 11 is connected to the cooling hood 6 and the smoke exhaust hood 12 respectively.

The heat insulation space can reduce the temperature outside the cooling cover 6, avoid burning operating personnel and improve the safety in use. The coupling stability of the cooling jacket 6 is improved.

In some embodiments, referring to fig. 1 to 4, the air guide mechanism includes a first air guide tube 7 and a second air guide tube 8 arranged along the up-down direction, an air inlet end of the first air guide tube 7 is communicated with the turn-back cavity 501, the connecting hood 5 is located in the cooling hood 6, the straw combustion furnace further includes an air guide hood 9, the air guide hood 9 is located upstream of the air guide mechanism, an air guide chamber 901 is arranged in the air guide hood 9, and an air outlet end of the first air guide tube 7 and an air inlet end of the second air guide tube 8 are respectively communicated with the air guide chamber 901.

The flue gas enters the smoke exhausting channel 1201 from the preheating part 101, flows out of the smoke exhausting channel 1201, enters the turn-back cavity 501, enters the first air duct 7 from the turn-back cavity 501, is discharged into the air guide chamber 901 from the air outlet end of the first air duct 7, finally enters the second air duct 8 and is discharged from the air outlet end of the second air duct 8. The scheme in this embodiment has further prolonged the flow path of flue gas, and the flue gas takes place the heat exchange with cooling medium when flowing in first air duct 7 and second air duct 8 respectively moreover, further reduces the temperature of flue gas through twice heat exchange.

In particular, the cooling hood 6 forms the outer wall of the straw combustion furnace.

Optionally, the cooling hood 6 includes a housing 601 disposed outside the smoke exhaust hood 12, and an end cap 602 disposed at the rear end of the housing 601.

In some embodiments, referring to fig. 1 to 4, the air guide cover 9 is provided with a cleaning opening, and the cleaning opening is provided with a cleaning door, and the cleaning door has a closed state for shielding the cleaning opening and an open state for communicating the cleaning opening with the outside.

When needing to clear up first air duct 7 or second air duct 8, switch the clearance door to the state of opening, clear up the dust in first air duct 7 or the second air duct 8, ensure that first air duct 7 and second air duct 8 are unobstructed, avoid first air duct 7 or second air duct 8 to block up the discharge that influences the flue gas, if cause the flue gas to gather the easy explosion risk that appears of flue gas.

In some embodiments, referring to fig. 1 to 4, the second furnace body 2 further includes a slag deposit portion 203 located downstream of the burnout portion 202, a slag discharge hole 2031 is formed at the bottom of the slag deposit portion 203, and the slag discharge hole 2031 is covered with a cover plate.

As the straw bundle is pushed in, the ash completely burned in the burnout section 202 is pushed into the slag trap 203, and the ash can be discharged from the slag discharge port 2031 by opening the cover plate. When the slag is not required to be discharged, the cover plate is closed, and the stability of the airflow in the second furnace body 2 is ensured.

Optionally, one side of the cover plate is rotatably connected with the second furnace body 2.

In some embodiments, referring to fig. 1 to 4, the straw combustion furnace further includes a first air blowing assembly disposed at a lower portion of the second furnace body 2, the first air blowing assembly includes a plurality of first air nozzles 4 disposed along the conveying direction, and the first air nozzles 4 are communicated with the second furnace body 2 for conveying air into the second furnace body 2.

According to the scheme in the embodiment, the first air nozzle 4 is arranged on the side wall of the lower portion of the combustion portion 201 to perform direct air distribution, the structure that air distribution is performed through a fire grate is replaced, the penetration capacity of combustion-supporting air is improved through the first air nozzle 4, the load intensity of primary combustion is exploded, and then straw bundles can be sufficiently combusted.

The primary air (air) supplied from the biomass boiler accounts for 2/3 or more of the total air amount required for combustion, and is a main factor for determining the combustion intensity of the fuel. Primary air of the existing biomass boiler is supplied into a hearth through a fire grate or an air distribution plate, the air flow rate through the fire grate holes is only about 2 m/s, the air speed cannot penetrate through compact straw bundles, only combustion can be carried out on the surfaces of the straw bundles, and the combustion intensity and the combustion speed are greatly influenced. The primary air distribution in the community is realized through the first air nozzle 4, the air flow rate through the air nozzle reaches 50 m/s, the straw bundle can be penetrated, the combustion is developed to the depth of the straw bundle, and the combustion strength is effectively improved.

In some embodiments, referring to fig. 1 to 4, two sets of the first blowing assemblies are provided, and the two sets of the first blowing assemblies are symmetrically arranged with respect to the axis of the second furnace body 2 as a symmetry axis. By simultaneously introducing air into the combustion part 201 from both sides of the second furnace body 2, the combustion intensity and the combustion speed are improved.

Alternatively, the first blowing means may be disposed in the combustion portion 201, or may be disposed in the combustion portion 201 and the burnout portion 202 to ensure that ash in the burnout portion 202 is sufficiently burned.

In some embodiments, referring to fig. 1 to 4, the straw combustion furnace further includes a second air blowing assembly disposed at an upper portion of the second furnace body 2 in the conveying direction, and the second air blowing assembly is communicated with the combustion portion 201, the second air blowing assembly includes a plurality of second air nozzles 13 distributed along a circumferential direction of the second furnace body 2, and the second air nozzles 13 are used for introducing air into the combustion portion 201.

Because the straw fuel has high volatile component content and is rapidly separated out in the state of carbon monoxide and hydrocarbon gas, the combustible gas has low density and is easy to gather at the upper part of the combustion part 201, and the second air nozzle 13 continuously supplies air at the top of the combustion part 201, so that the combustible gas gathered at the top of the combustion part 201 is beneficial to continuously burning, and the burning sufficiency of the straw bundle is ensured. The plurality of second air nozzles 13 are sequentially arranged along the circumferential direction of the second furnace body 2, so that air is uniformly introduced to the upper part of the combustion part 201, and the straw bundles in the combustion part 201 are fully combusted.

In some embodiments, referring to fig. 1 to 4, the second furnace body 2 is provided with a slag outlet at the bottom thereof, and the second furnace body 2 is provided with a grate 3, wherein the grate 3 is located at the slag outlet.

The straw bundles are burnt to form ash, large ash falls on the fire grate 3, and small ash passes through the fire grate 3 and is discharged out of the second furnace body 2. In addition, when the ash carried on the grate 3 reaches a certain weight, the ash is divided into small blocks by the grate 3 and discharged out of the second furnace body 2. The scheme in the embodiment can discharge the ash in the second furnace body 2 in time, and the ash is prevented from accumulating in the second furnace body 2 to influence the combustion of the straw bundle.

Optionally, the combustion part 201 or the burnout part 202 is provided with a slag hole, and the combustion part 201 and the burnout part 202 may be provided with slag holes.

The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, as any modifications, equivalents, improvements and the like made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.

Claims (10)

1. The straw combustion furnace is characterized by comprising a first furnace body, a second furnace body and a smoke exhaust hood, wherein,

the first furnace body forms a preheating part; the second furnace body is communicated with the first furnace body along the conveying direction of fuel, the second furnace body comprises a combustion part and a burnout part which are arranged along the conveying direction, a feed inlet is formed in the front end of the first furnace body, and the tail end of the second furnace body is closed; the smoke exhaust hood is arranged outside the second furnace body and provided with a smoke exhaust channel arranged along the conveying direction, the air inlet end of the smoke exhaust channel is communicated with the preheating part, and the air outlet end of the smoke exhaust channel discharges smoke outwards.

2. The straw combustion furnace as defined in claim 1, wherein the smoke exhaust hood is disposed above the second furnace body, and the smoke exhaust channel is located above the second furnace body.

3. The straw combustion furnace as set forth in claim 2, further comprising:

the cooling hood is arranged outside the smoke exhaust hood, a closed cooling space is formed between the cooling hood and the smoke exhaust hood, and a cooling medium is filled in the cooling space;

the connecting cover is connected with the tail end of the smoke exhaust cover, a turn-back cavity is formed between the connecting cover and the second furnace body, and the turn-back cavity is communicated with the smoke exhaust channel; and

the air guide mechanism is arranged in the cooling space, the air inlet end of the air guide mechanism is communicated with the air outlet end of the turn-back cavity, and the air outlet end of the air guide mechanism is used for discharging smoke.

4. The straw combustion furnace as set forth in claim 3, wherein a heat insulation space is provided between the cooling hood and the smoke exhaust hood, and a support plate is provided in the heat insulation space and connected to the cooling hood and the smoke exhaust hood, respectively.

5. The straw combustion furnace as set forth in claim 3, wherein the air guide mechanism includes a first air guide tube and a second air guide tube arranged in an up-down direction, an air inlet end of the first air guide tube is communicated with the turn-back chamber, the connecting hood is located in the cooling hood, and the straw combustion furnace further includes:

and the air guide cover is positioned at the upper stream of the air guide mechanism, an air guide chamber is arranged in the air guide cover, and the air outlet end of the first air guide pipe and the air inlet end of the second air guide pipe are respectively communicated with the air guide chamber.

6. The straw combustion furnace as set forth in claim 5, wherein the air guide hood is provided with a cleaning opening, and a cleaning door is provided on the cleaning opening, the cleaning door having a closed state in which the cleaning opening is shielded, and an open state in which the cleaning opening is communicated with the outside.

7. The straw combustion furnace as set forth in claim 1, wherein the second furnace body further comprises a slag deposit portion located downstream of the burnout portion, a slag discharge port is opened at a bottom of the slag deposit portion, and a cover plate is covered on the slag discharge port.

8. The straw combustion furnace as set forth in claim 1, further comprising a first blowing assembly disposed at a lower portion of the second furnace body, the first blowing assembly including a plurality of first blowing nozzles disposed along the feeding direction, the first blowing nozzles being in communication with the second furnace body for feeding air into the second furnace body.

9. The straw combustion furnace as set forth in claim 8, wherein the first blowing assemblies are provided in two sets, and the two sets of the first blowing assemblies are symmetrically provided with respect to an axis of the second furnace body as a symmetry axis.

10. The straw combustion furnace as set forth in claim 8, further comprising a second air blowing assembly disposed at an upper portion of the second furnace body in the conveying direction and communicating with the combustion portion, wherein the second air blowing assembly includes a plurality of second air nozzles distributed along a circumferential direction of the second furnace body, and the second air nozzles are used for introducing air into the combustion portion.

Images