CN214120032U

CN214120032U - Porous medium combustor and kiln

Info

Publication number: CN214120032U
Application number: CN202023287324.8U
Authority: CN
Inventors: 付超; 项往; 任志恒; 孔凡磊; 李豪; 尹向南; 王乃豪; 战斗
Original assignee: Zhongke Zhuoyi Environmental Technology Dongguan Co ltd; Songshan Lake Materials Laboratory
Current assignee: Zhongke Zhuoyi Environmental Technology Dongguan Co ltd; Songshan Lake Materials Laboratory
Priority date: 2020-12-30
Filing date: 2020-12-30
Publication date: 2021-09-03
Anticipated expiration: 2030-12-30

Abstract

The application provides a porous medium combustor and kiln, relates to the combustor field. The porous medium combustor is provided with an air inlet, a premixing diffusion chamber and a combustion chamber which are communicated in sequence along the air inlet direction; the premixing diffusion chamber is internally provided with a gas distribution assembly, the gas distribution assembly is provided with a gas inlet end connected with the gas inlet, a gas outlet end corresponding to the combustion chamber and a plurality of diffusion layers which are arranged between the gas outlet end and the gas inlet end at intervals, each diffusion layer is provided with a plurality of barrier parts arranged at intervals, and a flow guide hole is formed between every two adjacent barrier parts; in the axial direction of the porous medium combustor, in at least two adjacent diffusion layers, the blocking part of one diffusion layer is arranged corresponding to the flow guide holes of the other diffusion layer, and the flow guide holes of the multiple diffusion layers are matched to form a plurality of diffusion channels communicated with the air outlet end and the air inlet end, so that when the longitudinal stroke is short, the longitudinal speed of the gas at one side of the gas distribution plate far away from the premixing diffusion chamber is basically kept consistent, and the gas can enter the porous medium more uniformly to be uniformly combusted.

Description

Porous medium combustor and kiln

Technical Field

The application relates to the field of burners, in particular to a porous medium burner and a furnace kiln.

Background

Firstly, the mixed gas of the existing porous medium burner is generally premixed and then directly enters the combustion chamber through the gas inlet, at this moment, if the longitudinal stroke of the gas between the combustion chamber and the gas inlet is short and the space is small, the gas is difficult to be uniformly diffused, and further the longitudinal velocity of the gas entering one side of the gas distribution plate of the combustion chamber, which is close to the porous medium layer, is unevenly distributed, and the gas cannot be uniformly combusted.

In addition, the existing kilns, such as the existing ceramic roller kiln burners, provide convection heating and radiation heating of high-temperature flue gas by free flame combustion, and the burners are arranged on the roller and under the roller in a staggered manner. The flow direction of the flame and the flue gas is as follows: the flow above the product and below the stick is parallel to the product. At the moment, the combustor provides heat through free flame combustion, so that the temperature gradient near the flame surface is large, the temperature is uneven, the temperature of the section of the kiln is easily uneven, and the ceramic firing has extremely high requirement on the uniformity of the temperature field of the section in the kiln. Especially for roller kilns with a kiln width of more than three meters, the non-uniform temperature field of the kiln section is one of the main reasons for reducing the ceramic firing yield, and the conventional burner actually mixes fuel gas and flue gas and then injects the mixture into the kiln for combustion, so that incomplete combustion is easy to occur and the combustion efficiency is reduced, therefore, the uniformity of the oxidation/reduction atmosphere in the kiln cannot be ensured, and meanwhile, local high temperature is easy to occur during combustion, so that the emission of nitrogen oxides is high.

In view of this, the present application is hereby presented.

SUMMERY OF THE UTILITY MODEL

It is an object of embodiments of the present application to provide a porous medium burner and kiln that is capable of ameliorating at least one of the above-mentioned technical problems.

In a first aspect, embodiments of the present application provide a porous medium burner, which has an air inlet, a premixing diffusion chamber and a combustion chamber, which are sequentially communicated, along an axial direction of the porous medium burner.

The gas distribution assembly is arranged in the premixing diffusion chamber, and is provided with a gas inlet end connected with a gas inlet, a gas outlet end corresponding to the combustion chamber and a plurality of diffusion layers arranged at intervals between the gas outlet end and the gas inlet end along the gas inlet direction of the porous medium combustor, each diffusion layer is provided with a plurality of blocking parts arranged at intervals, and a flow guide hole is formed between every two adjacent blocking parts.

In at least two adjacent diffusion layers along the air inlet direction of the porous medium combustor, the blocking part of one diffusion layer is arranged corresponding to the flow guide holes of the other diffusion layer, and the flow guide holes of the multiple diffusion layers are matched to form a plurality of diffusion channels communicated with the air outlet end and the air inlet end.

In the implementation process, because the barrier part of one diffusion layer is arranged corresponding to the diversion holes of the other diffusion layer in at least two adjacent diffusion layers along the air inlet direction of the porous medium burner, therefore, even under the condition of short longitudinal stroke of gas, the gas flow entering from the gas inlet end can be quickly shunted and diffused to the gas outlet end through the diffusion channel, so that the gas is uniformly distributed on one side of the gas distribution plate of the combustion chamber close to the premixing diffusion chamber, the longitudinal (namely, the axial direction of the porous medium combustor) speed of the gas on one side of the gas distribution plate far away from the premixing diffusion chamber is basically kept consistent, and the gas can more uniformly enter the porous medium for uniform combustion, meanwhile, the blocking part can block the airflow to a certain degree, so that certain interaction is generated between the blocked airflow and the new entering airflow due to different flow directions, and the gas and the combustion-supporting gas in the airflow are further mixed more uniformly.

In a possible embodiment, in any adjacent diffusion layers along the air inlet direction of the porous medium burner, the barrier part of one diffusion layer is arranged corresponding to the flow guide hole of the other diffusion layer.

In the implementation process, the blocking part of any one of the two diffusion layers is arranged corresponding to the diversion hole of the other diffusion layer, so that the diversion effect can be ensured to be more uniform.

In one possible embodiment, each diffusion layer contains a gradually larger number of barriers in the air intake direction of the porous medium burner.

In the implementation process, the number of the blocking parts contained in each diffusion layer is gradually increased, so that the gas flow is favorably shunted by the diffusion channel and diffused to the gas outlet end, and the difference between the longitudinal speeds of the gas is reduced before the gas enters the combustion section.

In one possible embodiment, the cross-sectional area of the outlet end is greater than the cross-sectional area of the inlet end.

By means of the arrangement, compared with a mode that the premixing chamber is internally provided with the air distribution assembly, the manufacturing cost is effectively reduced on the premise that air distribution is effectively achieved.

In one possible embodiment, the blocking portion is a cylinder.

In the implementation process, the blocking part is a cylinder, the gap between any two adjacent cylinders on the same layer is a diffusion hole, the arrangement is simple, the processing is convenient, the uniformity of the gas after the gas distribution assembly is shunted can be ensured, and the difference between the longitudinal speeds of the shunted gas before entering the combustion section is reduced.

Optionally, the blocking portion is cylindrical.

In the implementation process, the arrangement of the cylinder can reduce the impact of the airflow on the cylinder, prolong the service life of the cylinder and simultaneously facilitate the diversion of the airflow along the surface of the cylinder.

In one possible embodiment, the barriers in any two adjacent diffusion layers are arranged in parallel, and the distance between any two adjacent barriers in any two adjacent diffusion layers is equal.

That is, in arbitrary adjacent two-layer diffusion layer, the position of the water conservancy diversion hole of the barrier portion of one diffusion layer and another diffusion layer corresponds, through above-mentioned setting, guarantees that every gas flow can equally divide into two strands after the barrier portion basically, further guarantees the homogeneity of diffusion.

In a possible embodiment, the porous medium burner has a rectangular projected shape in a horizontal plane along the air intake direction, and the axis of each barrier is parallel to the width direction of the projected shape.

The cooperation of the setting direction of utilizing the blocking part and the shape of combustor guarantees that gas can be shunted and spread to the end of giving vent to anger through the diffusion passageway fast to guarantee as far as that the gas after the diffusion can cover the gas distribution board of combustion chamber basically.

In a possible embodiment, the premixing diffusion chamber comprises a first premixing part, a second premixing part and a third premixing part which are connected in sequence, wherein the third premixing part is connected with the combustion chamber, the width of the first premixing part is gradually reduced towards one side close to the third premixing part, and the width of the third premixing part is gradually reduced towards one side close to the first premixing part.

By means of the arrangement, the gas is enhanced to be uniformly distributed in a short longitudinal stroke, the flowing speed of the gas in the combustor body is improved so as to avoid tempering, and the safety of the porous medium combustor is improved.

In one possible embodiment, a gap is left between the gas outlet end and the combustion chamber.

The gap is arranged, so that the gas output from the gas outlet end can further flow, and the difference between the longitudinal speeds of the gas before entering the combustion section is further reduced.

In a second aspect, embodiments of the present application provide a kiln, which includes a kiln body, and a porous medium burner provided in the kiln body according to the first aspect of the present application, a combustion surface of the burner faces the kiln body.

In the implementation process, the porous medium burner is used for replacing the existing common open flame burner, so that the gas can be ensured to be burnt out when being sprayed out of the burner outlet, the temperature difference of the section of the kiln is improved, the local high temperature phenomenon is avoided, and the reduction of the product yield caused by the contact of products and flame for partial ceramic firing is avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

FIG. 1 is a schematic view of a porous media burner from a first perspective;

FIG. 2 is a schematic structural view of a porous medium burner from a second perspective;

FIG. 3 is a schematic structural view of a third perspective of the porous media burner;

FIG. 4 is a schematic diagram of an alternative embodiment of an air distribution assembly 150 b;

fig. 5 is a partially enlarged view of V in fig. 2.

Icon: 10-a porous medium burner; 110-a first housing; 120-a second housing; 130-an air inlet; 131-an air inlet pipe; 133-connecting tube; 135-flange; 140-a premix diffusion chamber; 141-a first premixing section; 143-a second premixing section; 145-a third premixing section; 150 a-a gas distribution assembly; 150 b-a gas distribution assembly; 151-inlet end; 153-an air outlet end; 154-a diffusion layer; 155-diffusion channel; 156-a blocking portion; 157-diversion holes; 160-a combustion chamber; 161-uniform distribution plate; 163-first porous media layer; 164-a second porous media layer; 170-smoke outlet; 180-an ignition electrode; 190-ignition detection mechanism.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present application, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the term "horizontal" does not mean that the component is required to be absolutely horizontal, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

Examples

A kiln (not shown) includes a kiln body, and a porous medium burner 10 disposed in the kiln body.

It should be noted that the porous medium burner 10 may be a revolving body, such as a cylinder, or a strip, and since the porous medium burner 10 is installed in a kiln, such as a ceramic roller kiln in this embodiment, referring to fig. 1, the longitudinal depth of the porous medium burner 10 along the axial direction is short, and the projection of the porous medium burner 10 on the horizontal plane along the axial direction is a rectangle, and the combustion surface of the porous medium burner 10 faces the inside of the kiln for supplying heat to the kiln.

Specifically, referring to fig. 2, the porous medium burner 10 includes a hollow casing, and the casing has an air inlet 130, a premixing diffusion chamber 140, a combustion chamber 160, and an exhaust port 170, which are sequentially connected to each other along an air intake direction of the porous medium burner 10. The air inlet direction refers to the direction from the air inlet end to the air outlet end, i.e. the direction indicated by X in fig. 2.

Specifically, the casing includes a first casing 110 defining a premixing diffusion chamber 140 and a second casing 120 defining a combustion chamber 160, the first casing 110 is made of metal, for example, the second casing 120 is made of pouring refractory castable, for example, the first casing 110 is connected with the second casing 120, the premixing diffusion chamber 140 is communicated with the combustion chamber 160, an end of the first casing 110 far away from the combustion chamber 160 is provided with an air inlet 130, and an end of the second casing 120 far away from the first casing 110 is provided with an exhaust port 170.

The number of the gas inlets 130 may be one, at this time, the gas inlets 130 are used for introducing premixed gas and combustion-supporting gas, the number of the gas inlets 130 may also be at least two, for example, two, three, and the like, at this time, each gas inlet 130 may separately introduce gas or combustion-supporting gas, or may directly introduce premixed gas and combustion-supporting gas. Hereinafter, the gas is used for either the fuel gas or the combustion-supporting gas alone or the premixed gas of the fuel gas and the combustion-supporting gas.

Referring to fig. 1, in the present embodiment, the number of the air inlets 130 is two, the two air inlets 130 are respectively connected with the air inlet pipes 131, the end portions of the two air inlet pipes 131 are converged on the same connecting pipe 133, wherein the end portion of the connecting pipe 133 is provided with a flange 135, and further, in order to reduce the volume of the porous medium burner 10, the porous medium burner is more suitable for being used in a kiln body, and the air inlet pipes 131 are bent pipes.

The premixed diffusion chamber 140 has a rectangular shape in a projection in a horizontal plane in the air intake direction of the porous medium burner 10.

Referring to fig. 3, the premixing diffusion chamber 140 includes a first premixing part 141, a second premixing part 143 and a third premixing part 145 connected in sequence along the air intake direction of the porous medium burner 10, wherein the third premixing part 145 is connected to the combustion chamber 160, and the first premixing part 141 is communicated with the air intake 130.

The cross-sectional area of the first premixing section 141 is gradually reduced toward the side adjacent to the third premixing section 145, and the cross-sectional area of the third premixing section 145 is gradually reduced toward the side adjacent to the first premixing section 141.

Specifically, in the present embodiment, the width of the first premixing section 141 is gradually reduced only toward the side near the third premixing section 145, and the width of the third premixing section 145 is gradually reduced only toward the side near the first premixing section 141.

Referring to fig. 2, an air distribution assembly 150a is disposed in the premixing diffusion chamber 140, and the air distribution assembly 150a has an air inlet 151 connected to the air inlet 130, an air outlet 153 corresponding to the combustion chamber 160, and a plurality of diffusion layers 154 disposed at intervals between the air outlet 153 and the air inlet 151.

Each diffusion layer 154 has a plurality of barriers 156 spaced apart from each other, and a flow guide hole is formed between two adjacent barriers 156. In the air inlet direction of the porous medium burner, in at least two adjacent diffusion layers 154, the barrier portion 156 of one diffusion layer is arranged corresponding to the flow guide holes 157 of the other diffusion layer, and the flow guide holes of the multiple diffusion layers are matched to form a plurality of diffusion channels 155 communicating the air outlet end 153 with the air inlet end 151, so that the air flow entering through the air inlet end 151 is divided by the diffusion channels 155 and diffused to the air outlet end 153 and then enters the combustion chamber 160.

In this embodiment, in any two adjacent diffusion layers 154, the barrier portion 156 of one diffusion layer is disposed corresponding to the flow guiding hole 157 of the other diffusion layer, so as to ensure the uniformity of flow distribution.

Wherein, the cross-sectional area of the gas outlet end 153 is larger than that of the gas inlet end 151.

That is, the cross-sectional area of the gas inlet 130 is smaller than the cross-sectional area of the gas outlet 153, wherein the cross-section here refers to the cross-section perpendicular to the gas inlet direction of the porous medium burner 10.

Optionally, the gas distribution assemblies 150a correspond to the gas inlets 130 one by one, so as to ensure that the gas entering from each gas inlet 130 is distributed and diffused.

Specifically, in order to ensure the diffusion and flow-splitting effects, from the air inlet 151 to the air outlet 153, the number of the blocking portions included in each diffusion layer 154 is gradually increased, that is, the number of the corresponding flow guiding holes included in each diffusion layer 154 is gradually increased, at this time, the flow guiding holes of any two adjacent diffusion layers 154 are arranged in a staggered manner along the axial direction of the porous medium burner 10 in the projection of the horizontal plane, and the flow guiding holes of the multiple diffusion layers 154 are matched to form the diffusion channel 155.

Referring to fig. 4, in an air distribution assembly 150b provided in some alternative embodiments of the present application, the diffusion layer 154 may be a plate, and the guiding holes are through holes formed thereon, wherein the guiding holes may be waist holes arranged in parallel along a width direction of the projection direction, and the blocking portion is a residual part of the plate between two guiding holes.

Referring to fig. 2 and 5, in the air distribution assembly 150a of the present embodiment, the blocking portions 156 are cylinders, and a flow guiding hole 157 is formed between any two adjacent blocking portions 156, which is more convenient to install and effectively saves the manufacturing cost compared to the arrangement of the plate.

In order to secure the uniformity of the dispersion of the gas, in the present embodiment, the barriers 156 in any adjacent two diffusion layers 154 are arranged in parallel, and the axis of each barrier 156 is parallel to the width direction of the projected shape.

Specifically, the distance between any adjacent two barrier sections 156 in any adjacent two diffusion layers 154 is equal. That is, in the air intake direction of the porous medium burner, in two adjacent diffusion layers 154, the projection of the axis of the barrier 156 of one diffusion layer 154 on the horizontal plane substantially coincides with the projection of the axis of the flow guide hole of the other diffusion layer 154 on the horizontal plane, and at this time, three barriers 156 in any two adjacent barriers 156 are distributed in an equilateral triangle, so as to ensure the uniformity of flow distribution.

The blocking portion 156 is a cylinder, including but not limited to a hollow cylinder, and may also be a solid cylinder, whether hollow or solid, and the cylinder may be a prism, an elliptic cylinder, or a cylinder.

In this embodiment, the blocking portion 156 is a cylinder, and since the surface of the cylinder is smooth and curved, the impact of the airflow on the cylinder can be reduced, the service life of the cylinder can be prolonged, and the airflow can be conveniently divided along the surface of the cylinder.

In any case, in order to further ensure the uniformity of the output of the gas and ensure that the gas can completely cover the communication part between the premixing diffusion chamber 140 and the combustion chamber 160, a gap is left between the gas outlet end 153 and the combustion chamber 160.

Referring to fig. 2, a uniform distribution plate 161 and a porous medium layer are disposed in the combustion chamber 160 along the air intake direction of the porous medium burner 10, wherein the porous medium layer is located at a side of the uniform distribution plate 161 away from the pre-mixing diffusion chamber 140, and the uniform distribution plate 161 has a plurality of through holes extending along the axial direction of the porous medium burner 10 to communicate the pre-mixing diffusion chamber 140 and the porous medium layer. Through the arrangement of the gas distribution assembly 150a and the gap, the longitudinal flow velocity difference of the gas before entering the uniform distribution plate 161 is ensured to be small, so that the longitudinal flow velocity of the gas output by the uniform distribution plate 161 is ensured to be basically uniform, and the gas uniformly enters the porous medium layer to be uniformly combusted.

Wherein the uniform distribution plate 161 is made of a refractory material.

The porous medium layer may be a single layer, in this embodiment, the porous medium layer includes a first porous medium layer 163 and a second porous medium layer 164 stacked along the porous medium burner 10, wherein the second porous medium layer 164 is located on a side of the first porous medium layer 163 away from the distribution plate 161, a pore diameter of the first porous medium layer 163 is smaller than a pore diameter of the second porous medium layer 164, specifically, the first porous medium layer 163 is, for example, a porous alumina fiberboard, and the second porous medium layer 164 is, for example, a porous ceramic silicon carbide layer.

The porous medium burner 10 further comprises an ignition electrode 180 and an ignition detection mechanism 190, the ignition electrode 180 is connected with the housing, the ignition electrode 180 is located on one side of the porous medium layer away from the uniform distribution plate 161 and is used for igniting gas in the porous medium, and the ignition detection mechanism 190 is located on one side of the porous medium layer away from the uniform distribution plate 161 and is used for monitoring an ignition state, for example, the ignition detection mechanism 190 is a thermocouple, for example, temperature changes identify whether ignition is performed or not and combustion changes.

Optionally, the porous medium burner 10 further includes a controller (not shown), the ignition electrode 180 and the ignition detection mechanism 190 are electrically connected to the controller, so that the controller remotely controls the ignition electrode 180 to ignite and extinguish, and the controller determines whether to ignite, change the combustion, and the like through information fed back by the ignition detection mechanism 190.

In summary, the porous medium burner provided by the application utilizes the arrangement of the gas distribution assembly, even under the condition that the longitudinal stroke of gas is short, the gas flow entering through the gas inlet end can be quickly divided and diffused to the gas outlet end through the diffusion channel, so that the gas is uniformly distributed on one side of the gas distribution plate of the combustion chamber close to the premixing diffusion chamber, the longitudinal (namely, the axial) speed of the gas on one side of the gas distribution plate far away from the premixing diffusion chamber is basically kept consistent, and the gas can uniformly enter the porous medium to be uniformly combusted. The kiln comprising the porous medium burner can ensure that fuel gas is burnt out when the fuel gas is sprayed out of the outlet of the burner, improve the temperature difference of the section of the kiln, avoid the phenomenon of local high temperature, and avoid the reduction of the yield of products caused by the contact of products and flame for the firing of partial ceramic.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. The porous medium burner is characterized by comprising an air inlet, a premixing diffusion chamber and a combustion chamber which are sequentially communicated along the air inlet direction;

the gas distribution assembly is arranged in the premixing diffusion chamber, and is provided with a gas inlet end connected with the gas inlet, a gas outlet end corresponding to the combustion chamber and a plurality of diffusion layers arranged at intervals between the gas outlet end and the gas inlet end along the axial direction of the porous medium combustor, each diffusion layer is provided with a plurality of barrier parts arranged at intervals, and a flow guide hole is formed between every two adjacent barrier parts;

2. The porous medium burner of claim 1, wherein the barrier of one diffusion layer is disposed corresponding to the flow guide holes of another diffusion layer in any adjacent diffusion layer along the air intake direction of the porous medium burner.

3. The porous medium burner of claim 1, wherein each of the diffusion layers has a gradually increasing number of the barriers in an intake direction of the porous medium burner.

4. The porous media burner of claim 1, wherein the cross-sectional area of the outlet end is greater than the cross-sectional area of the inlet end.

5. The porous media burner of claim 1, wherein the barrier is a cylinder.

6. The porous medium burner of claim 5, wherein the barriers in any two adjacent diffusion layers are arranged in parallel and the distance between any two adjacent barriers in any two adjacent diffusion layers is equal.

7. The porous medium burner of claim 4, wherein a projected shape of the premixed diffusion chamber in a horizontal plane along the air intake direction is rectangular, and an axis of each of the blocking portions is parallel to a width direction of the projected shape.

8. The porous medium burner of claim 1, wherein the premixing diffusion chamber comprises a first premixing portion, a second premixing portion and a third premixing portion connected in sequence, wherein the third premixing portion is connected to the combustion chamber, the cross-sectional area of the first premixing portion is gradually reduced toward a side close to the third premixing portion, and the cross-sectional area of the third premixing portion is gradually reduced toward a side close to the first premixing portion.

9. The porous medium burner of any one of claims 1 to 8, wherein a gap is left between the gas outlet end and the combustion chamber.

10. A kiln comprising a kiln body, and a porous medium burner as claimed in any one of claims 1 to 9 disposed in the kiln body with a combustion face of the porous medium burner facing into the kiln body.