Turbulence-enhanced incinerator

Abstract

The incinerator comprises a combustion chamber, a first flue, a second flue and a third flue which are sequentially communicated, the first flue, the second flue and the third flue form a turn-back type flue gas flow channel, and turbulent flow enhancing inner components are arranged at inlets of the second flue and the third flue. The cross section of the turbulence enhancing inner component is triangular, and one side edge of the turbulence enhancing inner component directly faces the incoming flow direction of smoke. When flue gas flows into the second flue and the third flue, the flue gas is more uniformly distributed on the cross sections of the flues due to the turbulent flow enhancing inner components arranged at the inlets of the second flue and the third flue, so that the utilization rate of a subsequent convection heat exchange surface is increased, the combustion mixing is enhanced, and the combustion efficiency is improved by eliminating a low-temperature region and improving the temperature uniformity. And coking and pollutant generation are inhibited. The turbulent flow enhancing inner components are arranged at the inlets of the second flue and the third flue to improve the flow field, and the flue gas heat exchanger is simple in structure, low in implementation difficulty and low in cost.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of incinerator, especially, relate to a turbulent flow enhanced incinerator. BACKGROUND

[0002] Mechanical grate incinerator is the mainstream technology for treating municipal solid waste at present. The hearth structure thereof usually comprises a combustion chamber with a grate as the core, and a first flue, a second flue and a third flue arranged in sequence for heat exchange. The high-temperature flue gas generated by combustion firstly performs radiation heat exchange in the first flue, and then enters the second and third flues to perform convection heat exchange for recovering heat energy.

[0003] However, in actual operation, when the high-temperature flue gas flows from the first flue with a large cross-sectional area into the second and third flues with a small cross-sectional area and needs to be diverted, due to flow inertia and sudden change of flow channel, serious uneven flow field distribution problems are easily caused at the entrance "throat" of the second and third flues. Specifically, the high-speed flue gas concentrates on one side of the flue entrance, while a large range of flow separation zone and backflow zone (i.e. "flow dead zone") is formed on the other side. This leads to that the flue gas cannot uniformly fill the entire flue cross section, resulting in many disadvantages: first, a large amount of high-temperature flue gas "short-circuits" through, and part of the heat exchange surface is in a low flow speed zone, resulting in low heat exchange efficiency; second, the high-speed flue gas concentrated on one side entrains fly ash and violently washes the first row of heat exchange tubes at the entrance, resulting in serious abrasion of the tube wall; third, the low-temperature zone on the leeward side makes the molten alkali metal salt in the flue gas easily adhere to the wall, causing coking and corrosion; fourth, the uneven flow field and the existing low-temperature zone provide a catalytic surface and a suitable temperature window for the recombination of pollutants such as dioxin, increasing the difficulty of pollutant control.

[0004] The prior art usually adopts the method of optimizing the overall flue geometry or adding a complex array of guide plates to improve the flow field. However, the former has great implementation difficulty and high cost when modifying the existing boiler, and the latter has a complex structure and is difficult to maintain. UTILITY MODEL CONTENTS

[0005] The main purpose of the utility model is to provide a turbulent flow enhanced incinerator, which can effectively solve the problems in the background art.

[0006] To achieve the above purpose, the utility model is implemented by the following technical solutions:

[0007] A turbulent flow enhanced incinerator, comprising a combustion chamber, a first flue, a second flue and a third flue connected in sequence, the first flue, the second flue and the third flue forming a U-turn type flue gas flow channel, a turbulent flow enhanced internal component being arranged at the entrance of the second flue and the third flue, the cross section of the turbulent flow enhanced internal component being triangular, and one side being opposite to the incoming flow direction of the flue gas.

[0008] Preferably, the turbulence enhancement inner member comprises a triangular cross-section shell and a circular tube arranged in the middle of the shell, a layer of refractory material is filled between the circular tube and the shell, the circular tube is communicated with the secondary air supply system of the incinerator to form an air cooling channel.

[0009] Preferably, the circular tube and the shell are connected by a plurality of cage structures, and the plurality of cage structures are arranged along the length direction of the circular tube and the shell.

[0010] Preferably, the cage structure comprises a plurality of connecting rods, one end of the connecting rod is fixedly connected with the circular tube, the other end is fixedly connected with the triangular apex or the midpoint of the side length of the shell, and a supporting rod is fixedly connected between adjacent connecting rods.

[0011] Preferably, the connection between the circular tube and the wall of the incinerator is in a mode that one end is fixed and the other end is freely supported.

[0012] Preferably, the shell and the circular tube are both metal, and the circular tube is a 310S stainless steel tube.

[0013] Preferably, the cross-section of the turbulence enhancement inner member is an equilateral triangle.

[0014] Preferably, a grate is arranged in the combustion chamber, a primary air inlet is arranged at the bottom of the grate, a feeding port is arranged on the sidewall above the grate, and a secondary air inlet is arranged on the inlet of the first flue.

[0015] Preferably, the first flue is an upward flue, the second flue is a downward flue, and the third flue is an upward flue, which together form the turning type flue gas flow channel.

[0016] The utility model provides a kind of incinerator of turbulence enhancement, with the following beneficial effects.

[0017] When flue gas flows into the second flue and the third flue, due to the turbulence enhancement inner member arranged at the inlet of the second flue and the third flue, the cross-section of the turbulence enhancement inner member is triangular, and one side length is opposite to the incoming flow direction of flue gas, the turbulence enhancement inner member can effectively disperse and divide the concentrated main airflow, guide it to leeward, and guide part of the airflow to deviate from the original flow dead zone, significantly enhance the turbulence intensity, so that flue gas is more evenly distributed on the cross-section of the flue, which not only improves the utilization rate of the subsequent convection heat transfer surface and strengthens the combustion mixing, but also suppresses coking and pollutant generation by eliminating low-temperature zones and improving temperature uniformity. The utility model improves the flow field by arranging the turbulence enhancement inner member at the inlet of the second flue and the third flue, which is simple in structure, easy to implement and low in cost. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a structural schematic view of the incinerator of the utility model.

[0019] Figure 2 It is a structural schematic view of the turbulent flow enhancement inner member of the utility model.

[0020] Figure 3 It is a structural schematic view of the cage type structure of the utility model.

[0021] In the figure: 1, combustion chamber; 2, first flue; 3, second flue; 4, third flue; 5, turbulent flow enhancement inner member; 51, outer shell; 52, round pipe; 53, refractory material layer; 54, cage type structure; 541, connecting rod; 542, support rod; 6, grate; 7, primary air inlet; 8, feeding port; 9, secondary air inlet. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the utility model more clear, the technical scheme in the utility model will be described clearly and completely below by combining with the drawings of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the ordinary skilled in the art without creative labor belong to the scope of protection of the utility model.

[0023] In the description of the utility model, it is understood that the orientation or position relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the utility model and simplifying the description, and is not indicative or implied that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model.

[0024] In addition, the terms "first", "second", "third", "fourth", "fifth", "sixth", "seventh" and "eighth" are only used for descriptive purpose and cannot be understood as indicating or implying relative importance or implicitly pointing out the number of the technical features indicated. Therefore, the features defined with "first", "second", "third", "fourth", "fifth", "sixth", "seventh" and "eighth" can explicitly or implicitly include one or more of the features. In the description of the utility model, the meaning of "multiple" is two or more than two, unless otherwise specifically limited. In addition, the terms "mounting", "connecting", "connection" should be broadly understood, for example, it can be fixed connection, or detachable connection, or integrally connected, it can be mechanical connection, or electrical connection, it can be directly connected, or indirectly connected through intermediate medium, it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the utility model can be understood according to specific circumstances.

[0025] With reference to Figure 1 The utility model provides a kind of turbulent enhancement incinerator, the incinerator includes combustion chamber 1, first flue 2, second flue 3 and third flue 4 in turn, and the first flue 2, second flue 3 and third flue 4 form the smoke flue of return type, and the inlet of second flue 3 and third flue 4 is provided with turbulent enhancement inner component 5, and the cross section of turbulent enhancement inner component 5 is triangle, and one side length is directly opposite the flow direction of flue gas.

[0026] Incinerator is numerous, in the embodiment, incinerator is specifically mechanical grate incinerator, and grate 6 is provided in combustion chamber 1, and primary air inlet 7 is provided at the bottom of grate 6, and the side wall of combustion chamber 1 is provided with feeding port 8 above grate 6, and the inlet of first flue 2 is provided with secondary air inlet 9 towards combustion chamber 1.

[0027] Further, in the embodiment, the first flue 2 is up flue, the second flue 3 is down flue, and the third flue 4 is up flue, to form the smoke flue of return type.

[0028] The incinerator is used, the garbage is put into from the feeding port 8, and the drying, pyrolysis, combustion and burning-out process is completed on the grate 6. The air required for combustion is partly sent into as primary air from the primary air inlet 7, and the other part is sent into as secondary air from the secondary air inlet 9. The high-temperature flue gas generated by garbage combustion enters the heat exchange in the turn-around type flue gas flow channel formed by the first flue 2, the second flue 3 and the third flue 4. When the flue gas flows into the second flue 3 and the third flue 4, the inlet of the second flue 3 and the third flue 4 is provided with the turbulence enhancement inner member 5, the cross section of the turbulence enhancement inner member 5 is triangular, and the length of one side is opposite to the incoming direction of the flue gas, the turbulence enhancement inner member 5 can effectively disperse and divide the concentrated main airflow, guide the airflow to the leeward, guide part of the airflow to deviate from the original flow dead zone, significantly enhance the turbulence intensity, and make the flue gas more uniformly distributed on the cross section of the flue, which not only improves the utilization rate of the subsequent convection heat exchange surface, but also strengthens the combustion mixing, and through the elimination of the low-temperature zone and the improvement of the temperature uniformity, the coking and pollutant generation are inhibited. The utility model improves the flow field by setting the turbulence enhancement inner member 5 at the inlet of the second flue 3 and the third flue 4, and has the advantages of simple structure, small implementation difficulty and low cost.

[0029] As a preferred embodiment, with reference to Figure 2 、 Figure 3 , the turbulence enhancement inner member 5 comprises an outer shell 51 with a triangular cross section and a circular tube 52 arranged in the middle of the outer shell 51, a layer of refractory material 53 is filled between the circular tube 52 and the outer shell 51, the circular tube 52 is communicated with the secondary air supply system of the incinerator to form an air cooling channel.

[0030] The outer shell-refractory layer-central circular tube forms a solid and high-temperature-resistant turbulence enhancement inner member 5, the circular tube 52 is communicated with the secondary air supply system of the incinerator to form an air cooling channel, the existing secondary air of the system is used to cool the turbulence enhancement inner member 5 to prevent high-temperature deformation or burning loss, and the reliability is greatly improved, and the cooling air is heated and then enters the first flue 2 as secondary air for recycling.

[0031] Calculation shows that even if the flue gas temperature at the inlet of the second flue 3 is as high as 1000 DEG C, under the action of the cooling air, the temperature of the pipe wall of the circular tube 52 can be controlled below 400 DEG C, which is far below the high-temperature strength limit of the refractory material, the temperature of the air after cooling increases by about 70 DEG C, then enters the first flue 2 from the secondary air inlet 9, and energy recycling is realized.

[0032] As a preferred embodiment, the circular tube 52 and the outer shell 51 are connected through a plurality of cage structures 54, and the plurality of cage structures 54 are arranged along the length direction of the circular tube 52 and the outer shell 51.

[0033] The cage structure 54 serves as a framework of the refractory layer 53 and the circular tube 52, which can ensure the bonding strength of the refractory layer 53 and the circular tube 52, prevent the refractory layer 53 from peeling off or falling off the circular tube 52 at high temperature, and uniformly transmit the load of the shell 51 and the refractory layer 53 to the circular tube 52. The cage structure 54 is arranged at intervals to avoid the thermal bridge effect and save materials while ensuring the connection strength.

[0034] As a preferred embodiment, a specific form of the cage structure 54 is provided, which includes a plurality of connecting rods 541, one end of each connecting rod 541 being fixedly connected to the circular tube 52, and the other end being fixedly connected to a triangular vertex or a midpoint of a side length of the shell 51, and a support rod 542 being fixedly connected between adjacent connecting rods 541.

[0035] As a preferred embodiment, the connection between the circular tube 52 and the incinerator wall is in the form of one end being fixed and the other end being freely supported.

[0036] The temperature in the incinerator changes dramatically, and the long circular tube 52 will inevitably expand and contract significantly. The "one end fixed and the other end freely supported" (i.e., hinged or sliding support) can effectively release thermal stress, prevent structural cracking, deformation or connection damage due to restricted expansion, and ensure the safety and service life of the internal components during long-term operation.

[0037] Specifically, the freely supported end accommodates and supports the pipe through a U-shaped sliding groove welded to the furnace body. The sliding groove has a radial gap between the outer wall of the pipe and the sliding groove, and a limiting plate is arranged above the sliding groove, so as to limit the vertical and lateral displacement of the pipe while allowing it to freely slide in the axial direction to release thermal expansion stress. The refractory layer and the shell are attached to the circular tube, and expansion joints are arranged at both ends of the circular tube.

[0038] As a preferred embodiment, the shell 51 and the circular tube 52 are both made of metal, and the circular tube 52 is a 310S stainless steel pipe. In this embodiment, a 310S stainless steel pipe with an outer diameter of 219 mm and a wall thickness of 8-20 mm is preferred. 310S stainless steel has excellent oxidation resistance, corrosion resistance and sufficient strength at high temperatures, making it an ideal choice for such high-temperature flue gas environments.

[0039] As a preferred embodiment, the cross section of the turbulent flow enhancing internal component 5 is a regular triangle, which has perfect symmetry and uniform streamline guiding ability in all directions, can most uniformly divide and guide the middle airflow to both sides, and can theoretically achieve the best flow uniformity, and the manufacturing and stress are also more uniform.

[0040] The above examples are only used to illustrate the technical solutions of the present application, and are not intended to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can still be modified, or some technical features therein can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A turbulent enhanced incinerator characterized by, The incinerator comprises a combustion chamber, a first flue, a second flue and a third flue connected in sequence, the first flue, the second flue and the third flue form a turn-back flue gas flow channel, a turbulence enhancement inner component is arranged at the inlet of the second flue and the third flue, the cross section of the turbulence enhancement inner component is triangular, and one side length is opposite to the incoming flow direction of flue gas.

2. A turbulent enhanced incinerator according to claim 1 wherein, The turbulence enhancement inner component comprises a triangular cross section outer shell and a circular tube arranged in the middle of the outer shell, a refractory material layer is filled between the circular tube and the outer shell, the circular tube is communicated with the secondary air supply system of the incinerator to form an air cooling channel.

3. A turbulent enhanced incinerator according to claim 2, wherein The circular tube and the outer shell are connected by a plurality of cage structures, the plurality of cage structures are arranged along the length direction of the circular tube and the outer shell.

4. A turbulent-enhanced incinerator according to claim 3, characterised in that The cage structure comprises a plurality of connecting rods, one end of the connecting rod is fixedly connected with the circular tube, the other end is fixedly connected with the triangular apex or the midpoint of the side length of the outer shell, and a supporting rod is fixedly connected between adjacent connecting rods.

5. A turbulent enhanced incinerator as claimed in claim 2, wherein The connection between the circular tube and the furnace wall of the incinerator adopts a mode that one end is fixed and the other end is freely supported.

6. A turbulent enhanced incinerator as claimed in claim 2, wherein The outer shell and the circular tube are both metal, and the circular tube is a 310S stainless steel tube.

7. A turbulent enhanced incinerator as claimed in claim 1 wherein, The cross section of the turbulence enhancement inner component is an equilateral triangle.

8. A turbulent enhanced incinerator as claimed in claim 1 wherein, A grate is arranged in the combustion chamber, a primary air inlet is arranged at the bottom of the grate, a feeding port is arranged on the sidewall above the grate, and a secondary air inlet is arranged at the inlet of the first flue.

9. A turbulent enhanced incinerator as claimed in claim 1 wherein, The first flue is an upward flue, the second flue is a downward flue, and the third flue is an upward flue, which together form the turn-back flue gas flow channel.

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