CN113864783A

CN113864783A - Ammonia fuel fast pyrolysis grading injection gun

Info

Publication number: CN113864783A
Application number: CN202111040556.XA
Authority: CN
Inventors: 李水清; 宋民航; 黄骞; 李祎鹏; 靳星
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2021-09-06
Filing date: 2021-09-06
Publication date: 2021-12-31
Anticipated expiration: 2041-09-06
Also published as: CN113864783B

Abstract

The invention relates to an ammonia fuel fast pyrolysis grading injection gun. The ammonia fuel fast pyrolysis graded injection gun comprises: the heating pipe is internally provided with a heating component for heating and pyrolyzing the ammonia fuel; the injection subassembly, the injection subassembly with the heating pipe is connected, the injection subassembly includes a plurality of shower nozzles, the shower nozzle is used for after with the pyrolysis the high-speed blowout of ammonia fuel, the spray angle of shower nozzle can be adjusted. The ammonia fuel fast pyrolysis staged injection gun can enable the ammonia fuel delivered to the combustion furnace to quickly catch fire, stably and completely combust, and simultaneously reduce nitrogen oxides generated in the combustion process.

Description

Ammonia fuel fast pyrolysis grading injection gun

Technical Field

The invention relates to the technical field of fuel combustion, in particular to an ammonia fuel fast pyrolysis grading injection gun.

Background

The ammonia is used as a zero-carbon fuel and has high hydrogen storage density and easy useThe fuel has the advantages of low cost of liquefaction and unit energy storage, and the like, is a green energy carrier with a very promising prospect, is expected to become a basic fuel of a future power production system, and promotes low carbon emission in the fuel combustion and utilization process. However, ammonia fuels have low combustion strength, narrow flammability range, poor combustion stability, and NO_xHigh throughput is a problem that requires significant attention. One of the typical solutions to the above problem is to convert the combustible gas into a combustible gas more favorable for ignition and then burn the combustible gas, so as to reduce the difficulty in ignition, ensure more complete combustion and improve the utilization rate of ammonia fuel. Specifically, in solving the above problems, the rapid pyrolysis of ammonia fuel is realized, and the ammonia fuel is pyrolyzed into H₂The staged blending combustion of the combustible fuel and the constructed fuel promotes the stable combustion of ammonia after being sprayed into a hearth and reduces NO_xImportant measures for generation, but under the application scenes of the existing various fuel combustion technologies and the requirements of minimum reconstruction and capital investment, how to realize the quick pyrolysis and flexible and reasonable injection of ammonia fuel to reduce NO_xProduction has been an important concern in ammonia fuel utilization.

Aims to solve the problems of poor combustion stability and NO in the combustion and utilization process of ammonia fuel_xThe invention provides a high-yield ammonia fuel fast pyrolysis grading injection gun, which has the advantages of fast and stable combustion of ammonia fuel and reduction of NO_xThe device has the advantages of compact structure, small occupied space and low investment and operation cost, and is beneficial to popularization and application.

Disclosure of Invention

Based on the ammonia fuel fast pyrolysis grading injection gun, the ammonia fuel conveyed to the combustion furnace can be easily and rapidly ignited, and can be stably and completely combusted, and nitrogen oxides generated in the combustion process are reduced.

An ammonia fuel fast pyrolysis staged injection lance comprising:

the heating pipe is internally provided with a heating component for heating and pyrolyzing the ammonia fuel;

the injection subassembly, the injection subassembly with the heating pipe is connected, the injection subassembly includes a plurality of shower nozzles, the shower nozzle is used for with the pyrolysis after the ammonia fuel blowout, the spray angle of shower nozzle can be adjusted.

In one embodiment, the heating assembly includes a first heating element and a second heating element, the second heating element includes a closed end close to the fuel inlet and a first open end far away from the fuel inlet, the first heating element extends into the inner cavity of the second heating element from the first open end, the first heating element includes a second open end close to the fuel inlet and a third open end far away from the fuel inlet, a first heating zone is formed between the second heating element and the tube wall of the heating tube, a second heating zone is formed between the first heating element and the second heating element, a third heating zone is formed in the inner cavity of the first heating element, and the ammonia fuel can flow through the first heating zone, the second heating zone and the third heating zone in sequence.

In one embodiment, the heating pipe includes a flared section communicating with the fuel inlet, and a space of the first heating zone is gradually increased in a direction from the fuel inlet to the heating pipe.

In one embodiment, the first heating member and the second heating member are spiral electric heating wires, a filler is embedded in a gap between two adjacent circles of the electric heating wires, the filler and the electric heating wires are fixedly connected into a whole, the radial dimension of the inner wall of the filler is larger than that of the inner wall of the electric heating wires, and the radial dimension of the outer wall of the filler is smaller than that of the outer wall of the electric heating wires.

In one embodiment, the ammonia fuel fast pyrolysis staged injection gun further comprises a transition pipe, one end of the transition pipe is connected with the heating pipe, the other end of the transition pipe is connected with the injection assembly, the transition pipe comprises an inner pipe and an outer pipe, and a heat storage layer is filled between the inner pipe and the outer pipe.

In one embodiment, the spraying assembly comprises a mounting part and a rotating shaft, the mounting part is connected with the heating pipe, the rotating shaft is fixed on the mounting part, and each spraying head is sleeved on one rotating shaft and is rotatably connected with the rotating shaft; the ammonia fuel fast pyrolysis graded injection gun further comprises a limiting assembly, the limiting assembly is connected with the injection assembly, and the limiting assembly is used for limiting the spray head at the current injection angle.

In one embodiment, the limiting assembly includes a limiting member, the limiting member is detachably connected to the mounting member, and in a limiting state, the limiting member is fixedly connected to the mounting member, and the limiting member abuts against the nozzle to limit the rotation of the nozzle; under the rotation state, the fixed relation of locating part with the installed part is relieved, just the locating part with the shower nozzle separation.

In one embodiment, the spraying assembly further comprises guide pieces, the guide pieces are connected with the mounting pieces, a guide groove is defined between every two adjacent guide pieces, the spraying head extends into the guide groove and is attached to the groove wall of the guide groove, and the attachment area is an arc surface.

In one embodiment, a partition plate is arranged inside the nozzle, a first spraying cavity and a second spraying cavity for spraying the ammonia fuel are respectively arranged on two sides of the partition plate, and a protrusion is arranged on the surface of the partition plate.

Above-mentioned hierarchical spray gun of ammonia fuel fast pyrolysis, heating element in the heating tube can heat fuel, makes fuel intensification and carries out the pyrolysis, and the fuel after the pyrolysis is again followed the shower nozzle blowout and is burnt. The combustion difficulty of the fuel is reduced through pyrolysis, so that ignition is easier, complete combustion is easier to realize during combustion, the fuel is more sufficiently combusted, and the generation of nitrogen oxides can be reduced; meanwhile, the injection angle of the nozzle can be adjusted, so that the injection angle of the nozzle can be adjusted according to the flame distribution condition in the combustion furnace, and the injection of multiple fuel strands at different positions is constructed, thereby realizing the staged combustion of the fuel and inhibiting the generation of nitrogen oxides in the combustion process.

Drawings

FIG. 1 is a schematic diagram of the overall structure of an ammonia-fueled fast pyrolysis staged injection gun in one embodiment of the present invention;

FIG. 2 is a cross-sectional view of an ammonia fuel fast pyrolysis staged injection gun;

FIG. 3 is a cross-sectional view taken along A-A of FIG. 1;

FIG. 4 is a left side view of the ammonia fuel fast pyrolysis staged injection gun of FIG. 1;

FIG. 5 is a schematic diagram of a portion of the injector assembly of the ammonia fuel fast pyrolysis staged injection gun of FIG. 1;

FIG. 6 is a cross-sectional view taken along line B-B of FIG. 5;

FIG. 7 is a partial schematic structural view of the mounting member and guide member of the jetting assembly of FIG. 5;

FIG. 8 is a schematic view of the ammonia fuel fast pyrolysis staged injection lance of FIG. 1 disposed in the center of the burner;

FIG. 9 is a schematic illustration of the placement of the ammonia-fueled fast pyrolysis staged injection lance of FIG. 1 within the overfire air passage of the burner;

FIG. 10 is a schematic illustration of the ammonia fuel fast pyrolysis staged injection lance of FIG. 1 disposed adjacent a side of a burner;

FIG. 11 is a schematic view of the ammonia fuel fast pyrolysis staged injection lance of FIG. 1 disposed in a vertical side wall of a furnace;

FIG. 12 is a schematic view showing the direction of flow of the gas stream in the ammonia fuel pin pyrolysis staged spray gun of FIG. 1.

Reference numerals:

inlet pipe 100, fuel inlet 110;

a heating tube 200, a first heating zone 211, a second heating zone 212, a third heating zone 213, a flaring segment 221, a cylindrical segment 222, a necking segment 223;

a heating assembly 300, a first heating member 310, a second heating member 320, a first heating section 321, a second heating section 322, and a filler 330;

transition pipe 400, inner pipe 411, outer pipe 412, heat storage layer 413, first transition section 421, second transition section 422, and third transition section 423;

the spraying assembly 500, the mounting member 510, the side plate 511, the connecting plate 512, the spraying head 520, the opening 521, the separation plate 522, the protrusion 523, the first cambered surface 524, the rotating shaft 530, the guide member 540, the guide groove 541, the second cambered surface 542 and the protective cover 550;

a stop bolt 600;

a furnace 700;

a burner 800.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1, 2 and 8, an ammonia fuel fast pyrolysis staged injection lance according to an embodiment of the present invention may be used to deliver ammonia fuel into a furnace 700 such that the ammonia fuel is combusted in the furnace 700. In the following embodiments, the present embodiment is described by taking ammonia fuel as an example, but the device is not limited to delivering ammonia fuel, and other fuels with similar properties may be used. The ammonia fuel fast pyrolysis graded injection gun comprises a heating pipe 200 and an injection assembly 500, wherein a heating assembly 300 is arranged in the heating pipe 200, and the heating assembly 300 can heat ammonia fuel flowing through the heating pipe 200, so that the ammonia fuel is fast pyrolyzed. The injection assembly 500 is connected with the heating pipe 200, the injection assembly 500 comprises a plurality of spray heads 520, the spray heads 520 can spray the pyrolyzed ammonia fuel, and the spray angle of the spray heads 520 can be adjusted. In this embodiment, the heating element 300 in the heating pipe 200 can rapidly heat the ammonia fuel, so that the ammonia fuel is heated and rapidly pyrolyzed, and the pyrolyzed ammonia fuel is sprayed out from the nozzle 520 to be combusted. The ammonia fuel can be decomposed into combustible hydrogen through pyrolysis, so that the combustion difficulty can be reduced, the ignition is easier, the complete combustion is easier to realize during the combustion, the burnout rate of the ammonia fuel can be greatly improved, and the generation of nitrogen oxides in the combustion process is reduced. In addition, the injection angle of the nozzle 520 can be adjusted, so that the injection angle of the nozzle 520 can be adjusted according to the flame distribution condition in the combustion furnace, and multiple strands of ammonia fuel can be injected at different positions, thereby realizing the staged combustion of the ammonia fuel and inhibiting the generation of nitrogen oxides in the combustion process to the maximum extent.

Referring to fig. 2, preferably, in some embodiments, the heating assembly 300 includes a plurality of heating members, a plurality of heating zones for flowing fuel are formed between the heating members and the heating pipe 200, adjacent heating zones are communicated with each other, and the adjacent heating zones can provide different flowing directions for the ammonia fuel. For example, the ammonia fuel flows in opposite directions or vertically in adjacent heating zones, and the flow direction of the ammonia fuel is changed when the ammonia fuel flows from one heating zone to the adjacent heating zone. When ammonia fuel flow direction changed, flow velocity can reduce, and the time that makes ammonia fuel flow through heating element 300 required is more of a specified duration to can be more abundant be heated, more abundant pyrolysis, make spun fuel more easily, combustion strength is higher, changes in abundant burning. And by the flow channel arrangement mode for switching the flow direction, under the condition that the lengths of the flow channels are equal, the length of the heating assembly 300 along the axial direction can be smaller, and correspondingly, the length of the heating pipe 200 along the axial direction is smaller, so that the mode has obvious advantages when the axial size of the ammonia fuel fast pyrolysis staged injection gun is greatly limited, and the radial size is not excessively required.

Specifically, in some embodiments, the heating assembly 300 includes a first heating element 310 and a second heating element 320, the second heating element 320 includes a closed end near the fuel inlet 110 and a first open end far away from the fuel inlet 110, the first heating element 310 extends from the first open end into an inner cavity of the second heating element 320, the first heating element 310 includes a second open end near the fuel inlet 110 and a third open end far away from the fuel inlet 110, a first heating zone 211 is formed between the second heating element 320 and the tube wall of the heating tube 200, a second heating zone 212 is formed between the first heating element 310 and the second heating element 320, the inner cavity of the first heating element 310 forms a third heating zone 213, and the fuel can sequentially flow through the first heating zone 211, the second heating zone 212 and the third heating zone 213.

Specifically, the ammonia fuel fast pyrolysis staged injection gun includes an inlet pipe 100, the inlet pipe 100 is connected to a heating pipe 200, and ammonia fuel enters from a fuel inlet 110 at the end of the inlet pipe 100 and flows into the heating pipe 200. Of course, in other embodiments, the ammonia fuel may be directly fed into the heating pipe 200 from the ammonia storage tank through a hose or the like.

Referring to fig. 2 and 12, in particular, the second heating member 320 has a hollow interior, and an end thereof close to the fuel inlet 110 is closed, i.e., forms a closed end, and an end thereof far from the fuel inlet 110 has an opening, i.e., forms a first open end. The first heating member 310 is hollow inside and has both ends open, i.e., forming a second open end close to the fuel inlet 110 and a third open end remote from the fuel inlet 110. The first heating member 310 extends from the first open end partially into the cavity of the second heating member 320, i.e., a portion of the first heating member 310 extends into the cavity of the second heating member 320 and a portion is still outside the second heating member 320. Specifically, in the view of fig. 2, when the ammonia fuel flows from the inlet pipe 100 to the connection with the heating pipe 200 toward the left, the ammonia fuel will continue to flow into the first heating region 211 between the second heating element 320 and the pipe wall of the heating pipe 200 toward the left, and the end of the heating pipe 200 away from the fuel inlet 110 is closed, so that when the ammonia fuel flows thereto, the ammonia fuel will turn back toward the right, reach the first open end, and then flow into the second heating region 212 between the first heating element 310 and the second heating element 320, and when the ammonia fuel flows to the region close to the closed end, the ammonia fuel will turn back toward the left again, reach the second open end, and flow into the inner cavity of the first heating element 310, flow into the inner cavity of the first heating element 310 toward the left to the third open end, and flow out of the heating element 300 from the third open end. When the heating assembly 300 is disposed as described above, the first heating zone 211, the second heating zone 212, and the third heating zone 213 may form an "S" shaped flow path. When the heating unit 300 is arranged in this manner, the heating unit 300 can be made smaller in the axial direction with the same length of the flow path, and correspondingly, the heating pipe 200 can be made smaller in the axial direction, which is a significant advantage when there is a large limitation on the axial dimension of the ammonia fuel fast pyrolysis staged injection gun without an excessive requirement on the radial dimension.

Preferably, in some embodiments, the heating tube 200 includes a flared section 221 communicating with the fuel inlet 110, and a space of the first heating region 211 gradually increases within the flared section 221 in a direction from the fuel inlet 110 to the heating tube 200. Specifically, the flared section 221 is connected to the inlet pipe 100 and communicates internally therewith. As previously described, the first, second, and

third heating zones

211, 212, and 213 may form an "S" shaped flow path. When the ammonia fuel flows in the bent flow path, the ammonia fuel is turned back for multiple times, the flow direction is changed for multiple times, and meanwhile, the flow channel sectional area of the first heating area 211 is increased, so that the flow speed of the air flow is greatly reduced, the retention time of the ammonia fuel in the heating area can be prolonged, the time required by the ammonia fuel flowing through the heating assembly 300 is longer, and the ammonia fuel can be heated and pyrolyzed more fully. Meanwhile, in the case of equal flow path lengths, this configuration allows the heating assembly 300 to have a smaller length in the axial direction, and correspondingly, the heating tube 200 to have a smaller length in the axial direction, which is a significant advantage when there is a large limitation on the axial dimension of the ammonia fuel fast pyrolysis staged injection gun without an excessive requirement on the radial dimension.

Specifically, the heating pipe 200 includes a flared section 221, a cylindrical section 222 and a constricted section 223 connected in sequence and communicating with each other, and the constricted section 223 and the flared section 221 are respectively located at two end regions of the heating pipe 200. The flared section 221 is in the shape of a hollow circular truncated cone, both ends of which are open, and the radial dimension of the flared section 221 gradually increases in the direction from the fuel inlet 110 to the heating pipe 200. The cylindrical section 222 is in the shape of a ring with a hollow interior and open ends. The tapered section 223 is in the form of a hollow circular truncated cone, and one end connected to the cylindrical section 222 is open and the other end is closed. The radial dimension of the throat section 223 gradually decreases in a direction from the fuel inlet 110 to the heating pipe 200.

Further, in some embodiments, the second heating member 320 includes a first heating section 321 and a second heating section 322, the first heating section 321 is annular, and the first heating section 321 is sleeved outside the first heating member 310. The second heating section 322 is closed at one end near the inlet tube 100 to form a closed end; the second heating section 322 is open at an end thereof remote from the inlet pipe 100, and is connected to the first heating section 321 to communicate with the inside thereof. In the direction from the inlet pipe 100 to the heating pipe 200, the radial dimension of the second heating section 322 gradually increases, i.e., the second heating section 322 is tapered with a hollow interior and an open bottom. Of course, in other embodiments, the second heating element 320 may be eliminated from the second heating section 322 and the end of the first heating section 321 adjacent to the inlet pipe 100 is directly closed to form a closed end.

In some embodiments, the first heating element 310 and the second heating element 320 are both spiral electric heating wires and are coaxial with the heating tube 200, a filler 330 is embedded in a gap between two adjacent turns of the electric heating wires, and the filler 330 and the electric heating wires are fixedly connected into a whole. Specifically, the filler may be a material with good thermal conductivity and high temperature resistance, such as silicon carbide, and the filler is sintered and cured after the powdery silicon carbide is filled in the gap between two adjacent circles of the electric heating wire, so as to be connected with the electric heating wire into a whole. By providing the filler 330, the electric heating wire can be connected as one body, thereby improving the strength thereof. In addition, compared with the electric heating wire with gaps, the electric heating wire connected into a whole has better heat distribution continuity along the axial direction and more uniform temperature distribution in all areas along the axial direction.

Preferably, in some embodiments, the radial dimension of the inner wall of the filler 330 is greater than the radial dimension of the inner wall of the heating element in which the electric heating wire is enclosed, and the radial dimension of the outer wall of the filler 330 is less than the radial dimension of the outer wall of the heating element in which the electric heating wire is enclosed. Therefore, the inner wall and the outer wall of the entire heating member are formed in an uneven shape along the axial direction of the heating pipe 200. The uneven inner wall and the uneven outer wall are beneficial to the generation of turbulence when the ammonia fuel flows through, and more sufficient heat exchange is carried out with the inner wall and the outer wall, so that the rapid temperature rise of the ammonia fuel is promoted.

In many of the above embodiments, the ammonia fuel flows in opposite directions in adjacent heating zones. Similarly, in other embodiments, the ammonia fuel flows vertically in adjacent heating zones. The heating assembly 300 may still be arranged as described above with reference to the embodiments, but the shape or the arrangement angle of the heating elements is different. For example, the second heating member 320 may be arranged to have a radial size gradually decreasing from right to left, in which case the included angle between the first heating region 211 and the second heating region 212 is acute, and correspondingly, the included angle of the flow direction of the ammonia fuel in the first heating region 211 and the second heating region 212 is also acute.

In the above embodiments, only two heating members are provided, and similarly, in other embodiments, it is also possible to increase the heating members and increase the number of times of return of the ammonia fuel in the manner described above with reference to the above embodiments, thereby achieving more sufficient pyrolysis. For example, a third heating member may be additionally provided inside the first heating member 310, and the third heating member has a structure similar to that of the second heating member 320, and is hollow inside, and has a right end closed to the left end opening. The third heating element extends from the third open end portion into the cavity of the first heating element 310. Thus, after the ammonia fuel flows into the cavity of the second heating member 320, the ammonia fuel enters between the second heating member 320 and the third heating member, and returns back again when reaching the opening at the left end of the third heating member, and enters the cavity of the third heating member.

In other embodiments, the heating assembly includes a first heating element having an annular shape, and an inner cavity of the first heating element forms a heating zone through which the fuel flows. Specifically, the first heating member may be a spiral electric heating wire, and the whole is annular. The first heating member is coaxial with the heating pipe 200, and the inner wall setting of heating pipe 200 can be hugged closely to the first heating member, and the external diameter of first heating member is about the same with the internal diameter of heating pipe 200 promptly, and the inside cavity of first heating member and both ends all are the opening form. The ammonia fuel may enter the first heating member through an opening at one end and exit the first heating member through an opening at the other end, and the first heating member may heat the ammonia fuel to pyrolyze the ammonia fuel as the ammonia fuel flows through the first heating member.

Alternatively, in some embodiments, the first heating element forms a heating zone between the tube wall of the heating tube 200 through which the fuel flows. Specifically, the first heating member may be a columnar heating member such as a prism or a cylinder, and the first heating member is coaxial with the heating pipe 200, and the radial dimension of the first heating member is smaller than the inner diameter of the heating pipe 200. When the ammonia fuel flows through the space between the first heating member and the pipe wall of the heating pipe 200, the first heating member may heat it so that it is pyrolyzed.

In other embodiments, the heating assembly includes a first heating member and an annular second heating member, the second heating member is sleeved outside the first heating member and spaced apart from the first heating member, and a heating region for fuel to flow through is formed between the first heating member and the second heating member. Specifically, the first heating member is coaxial with the second heating member, the first heating member may be columnar, the second heating member is hollow inside and has both ends open, and the radial dimension of the first heating member is smaller than that of the inner ring of the second heating member. When ammonia fuel flows through the space between the first heating element and the second heating element, the first heating element and the second heating element heat the ammonia fuel at the same time, so that the temperature of the ammonia fuel can be increased to the pyrolysis temperature as soon as possible, and the ammonia fuel is pyrolyzed more fully.

In some embodiments, the ammonia-fueled fast pyrolysis staged injection lance further includes a transition tube 400, and one end of the transition tube 400 is connected to the heating tube 200, and the other end is connected to the injection assembly 500, i.e., the injection assembly 500 is connected to the heating tube 200 through the transition tube 400. The transition pipe 400 includes an inner pipe 411 and an outer pipe 412, and a heat storage layer 413 is filled between the inner pipe 411 and the outer pipe 412.

Specifically, the ammonia fuel fast pyrolysis staged injection gun comprises an inlet pipe 100, a heating pipe 200, a heating assembly 300, a transition pipe 400, an injection assembly 500 and the like, wherein the inlet pipe 100, the heating pipe 200, the transition pipe 400 and the injection assembly 500 are sequentially connected in the axial direction. Ammonia fuel enters the inlet tube 100 from the fuel inlet 110 at the end of the inlet tube 100 and flows through the heating tube 200 and the transition tube 400 in sequence to the injector assembly 500. One end of the outer tube 412 of the transition tube 400 is fixedly connected to the heating tube 200, and the other end is fixedly connected to the injection assembly 500. The inner pipe 411 of the transition pipe 400 has one end connected to and communicating with the inside of the first heating member 310 and the other end communicating with the inlet of the spray head 520 of the spray assembly 500. The ammonia fuel in the inner chamber (i.e., the third heating zone 213) of the first heating member 310 flows into the inner pipe 411 and further into the injection head 520. Through setting up heat storage layer 413, can make the ammonia fuel after carrying out the pyrolysis in heating pipe 200 the heat dissipation less after entering inner tube 411, still be in high temperature state before flowing into shower nozzle 520, the partial ammonia fuel that has not come to pyrolysis can continue the pyrolysis in this section region to make the pyrolysis more thorough. In addition, as mentioned above, the transportation device is extended into the combustion furnace 700 when in use, and the heat storage layer 413 can absorb the radiant heat of the flame in the combustion furnace 700, so that the temperature in the inner tube 411 can be kept high, which is beneficial to the continuous pyrolysis of the ammonia fuel in this region. Specifically, the heat storage layer 413 may be formed by filling a sensible heat material, such as ceramic, etc., or a phase change material, such as nitrate, etc., between the inner tube 411 and the outer tube 412. Specifically, the transition pipe 400 includes a first transition section 421, a second transition section 422, and a third transition section 423 that are sequentially connected in the axial direction. The cross section of the outer wall of the first transition section 421 is circular, the cross section of the outer wall of the third transition section 423 is rectangular, and the cross section of the outer wall of the second transition section 422 transitions from circular to rectangular to connect the first transition section 421 and the third transition section 423. Referring to fig. 2-4, third transition piece 423 is coupled to injection assembly 500. The plurality of spray heads 520 within spray assembly 500 are arranged in a row radially of transition duct 400, i.e., at the angle shown in the drawings, the plurality of spray heads 520 are arranged in a vertical orientation. The overall spray assembly 500 is designed to be rectangular, and the cross section of the outer wall of the third transition section 423 is also rectangular, so that the spray assembly 500 with such a shape can be conveniently installed. Of course, if the outer shape of the injection assembly 500 is designed to be circular, the cross-sectional shape of the outer wall of the entire transition duct 400 may be the same.

Referring to fig. 1, 2, and 5 to 7, in some embodiments, the spraying assembly 500 includes a mounting member 510 and a rotating shaft 530, the mounting member 510 is connected to the heating tube 200, the rotating shaft 530 is fixed to the mounting member 510, and each spraying head 520 is sleeved on one rotating shaft 530 and is rotatably connected to the same. Specifically, the spray module 500 further includes a shield 550, the shield 550 is connected to the heating pipe 200 through a transition pipe 400, and the shield 550 has a rectangular parallelepiped shape, is hollow inside, and has an opening at the spraying side of the spray head 520. Specifically, the shield 550 and the mounting member 510 are both fixedly connected to the end of the third transition section 423, the shield 550 is covered outside the mounting member 510, and the shield 550 and the mounting member are fixedly connected to each other, so that the components inside the shield 550 can be protected. The mounting member 510 includes two side plates 511 spaced apart from each other, and a connecting plate 512 integrally connecting the two side plates 511. The nozzle 520 is disposed between the two side plates 511, the rotating shaft 530 is also disposed between the two side plates 511, two ends of the rotating shaft 530 are respectively fixedly connected to the corresponding side plates 511, and the nozzle 520 is sleeved on the rotating shaft 530. Injector head 520 may be rotated relative to rotational axis 530 to adjust the angle of ammonia fuel injection. As described above, a plurality of heads 520 are provided, and each head 520 may be rotated independently or simultaneously, so that the ejection angle of the ammonia fuel ejected from each head 520 may be more suitable for the flame conditions of the corresponding region. For staged combustion, reference may be made to the related art for specific locations in the furnace 700 when ammonia fuel is injected, and further description thereof is omitted here.

In some embodiments, the ammonia fuel fast pyrolysis staged injection gun further comprises a limiting assembly coupled to the injection assembly 500, the limiting assembly configured to limit the injector head 520 at a current injection angle. Specifically, after the spraying head 520 rotates to a preset position, the spraying head 520 is limited by the limiting assembly, so that the spraying head is stably maintained at the current position. Specifically, in some embodiments, the limiting component includes a limiting member detachably connected to the mounting member 510, and in the limiting state, the limiting member is fixedly connected to the mounting member 510, and the limiting member abuts against the nozzle 520 to limit the rotation of the nozzle 520; in the rotating state, the fixing relationship between the limiting member and the mounting member 510 is released, and the limiting member is separated from the showerhead 520. Specifically, the limiting member includes a limiting rod and a limiting bolt 600. In the limit state, the limit rod passes through the side wall of the shield 550 and the side plate 511 of the mounting member 510 from the outside and abuts against the outer side wall of the nozzle 520, and the limit bolt is in threaded connection with the portion of the limit rod located outside the shield 550 to fix the position of the limit rod, thereby inhibiting the rotation of the nozzle 520. In a rotating state, the limit bolt is separated from the limit rod, and the limit rod can be withdrawn in a direction away from the spray head 520 and separated from the spray head 520, so that the spray head 520 can rotate around the rotating shaft 530. Preferably, two sets of limiting components are provided, and two limiting rods respectively pass through the shield 550 and the side plate 511 in sequence from two sides and abut against two outer side walls of the spray head 520 located at opposite sides. The two limiting rods are respectively abutted against the two outer side walls of the sprayer 520, so that the limiting effect can be enhanced, and the sprayer 520 can be more stably limited at the current position.

Preferably, in some embodiments, the spray assembly 500 further includes guide members 540, the guide members 540 are connected to the mounting member 510, a guide groove 541 is defined between adjacent guide members 540, the spray head 520 extends into the guide groove 541 and is attached to a groove wall of the guide groove 541, and the attachment area is an arc surface. Specifically, a plurality of guide members 540 are fixedly coupled between the two side plates 511 of the mounting member 510, and the shower head 520 is positioned between the adjacent two guide members 540 to define a guide groove 541. The nozzle 520 comprises a first cambered surface 524, the guide 540 comprises a second cambered surface 542, and the first cambered surface 524 and the second cambered surface 542 are attached to each other. In this way, when the spraying head 520 rotates around the rotating shaft 530, two side walls (i.e. two second arc surfaces 542) of the guiding groove 541 can guide the spraying head 520 to a certain extent, so that the first arc surface 524 rotates relative to the second arc surface 542, but the two arc surfaces are always attached to each other. The rotation of the spray head 520 about the rotation shaft 530 can be stabilized by the guide of the guide groove 541.

Preferably, in some embodiments, a partition plate 522 is provided inside the head 520, a first ejection chamber and a second ejection chamber for ejecting fuel are provided on both sides of the partition plate 522, respectively, and a protrusion 523 is provided on a surface of the partition plate 522. Specifically, the partition plate 522 is located between the two side plates 511, and is fixedly connected to both the two side plates 511, and protrusions 523 are distributed on the surfaces of both sides of the partition plate 522 in the thickness direction. When ammonia fuel enters the mounting member 510 from the transition pipe 400, the ammonia fuel enters the inner cavity of the nozzle 520 from the opening 521 of the nozzle 520, and the partition plate 522 divides the ammonia fuel into two parts, wherein one part flows into the first ejection cavity on one side of the partition plate 522, and the other part flows into the second ejection cavity on the other side of the partition plate 522, and the two parts are merged and ejected together at the outlet of the nozzle 520. When passing through the two sides of the partition plate 522, the ammonia fuel contacts the protrusions 523, the protrusions 523 can disturb the ammonia fuel airflow, enhance the turbulence characteristic after the ammonia fuel is sprayed out, promote the turbulence mixing between the ammonia fuel and the main flame, and ensure better overall combustion stability and burnout effect. Preferably, the rotating shaft 530 passes through the separation plate 522, so that the area of the nozzle 520, which is sleeved on the rotating shaft 530 and contacts with the rotating shaft 530, is larger, and the rotation is more stable.

In some embodiments, the combustion apparatus comprises the ammonia-fueled fast pyrolysis staged injection lance of any of the above embodiments, a burner 700, and a burner 800, wherein the burner 800 is coupled to the burner 700, and the ammonia-fueled fast pyrolysis staged injection lance extends at least partially into the burner 700. Referring to fig. 8-11, in particular, in general, at least the injection assembly 500 and transition tube 400 of the ammonia-fueled fast pyrolysis staged injection lance extend into the furnace 700. The angle and position of the ammonia fuel fast pyrolysis staged injection lance protruding into the furnace 700 are not limited, and may be any one of the positions shown in fig. 8 to 11, for example. In fig. 8, an ammonia fuel fast pyrolysis staged injection gun is disposed at the center of the burner 800, in fig. 9, the ammonia fuel fast pyrolysis staged injection gun is disposed in the overfire air passage of the burner 800, in fig. 10, the ammonia fuel fast pyrolysis staged injection gun is disposed at a side position adjacent to the burner 800, and in fig. 11, the ammonia fuel fast pyrolysis staged injection gun is disposed on a vertical sidewall of the furnace of the combustion furnace 700.

The invention has the beneficial effects that:

(1) the ammonia fuel of the invention can be used for rapid heatingThe de-grading spray gun realizes the rapid pyrolysis and the decomposition into H before the ammonia fuel is sprayed into the main flame by virtue of the design of an S-shaped axisymmetric reciprocating passage constructed by an electric heating wire and the use of an on-way heat storage layer₂And various gases with strong reaction activity participate in combustion, which is beneficial to the high-efficiency stable combustion utilization of ammonia;

(2) according to the ammonia fuel fast pyrolysis grading injection gun, the single body is of a rod-shaped structure, flexible arrangement can be performed on the inner part, the side surface or the side wall of a hearth of the burner under the condition of not changing the combustion organization mode of a main burner according to the type (a gas burner, a pulverized coal burner, a small industrial furnace burner and the like) and the actual spatial position of the main burner, and the whole occupied space is small;

(3) in the stage injection section, by designing a plurality of adjustable nozzles, the incidence direction of each nozzle can be adjusted based on different arrangement positions of the injection gun and the flame distribution form of the main burner, stage injection of a plurality of ammonia air flows at different positions is constructed, and stage combustion of ammonia fuel is realized, so that the ammonia fuel is rapidly pyrolyzed and stably combusted, and NO in the combustion process is inhibited_xGenerating;

(4) the ammonia fuel fast pyrolysis graded injection gun is suitable for fast heating pyrolysis of ammonia fuel, promoting and accelerating fast heating and reaction processes of mixed gas of ammonia gas and oxygen, ammonia gas and water vapor, ammonia gas and air and the like, and has strong fuel type adaptability.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. An ammonia-fueled fast pyrolysis staged injection lance comprising:

2. The ammonia-fueled fast pyrolysis staged spray gun according to claim 1, wherein the heating assembly comprises a plurality of heating elements, the heating elements and the heating tube together form a plurality of heating zones for flowing the fuel, adjacent heating zones are communicated with each other, and the adjacent heating zones can provide different flowing directions for the fuel.

3. The ammonia-fueled fast pyrolysis staged injection gun of claim 2, the heating assembly includes a first heating member and a second heating member, the second heating member including a closed end adjacent to the fuel inlet, and a first open end remote from the fuel inlet, the first heating element extending from the first open end portion into the interior cavity of the second heating element, the first heating element including a second open end proximate the fuel inlet, and a third opening end far away from the fuel inlet, a first heating area is formed between the second heating element and the pipe wall of the heating pipe, a second heating area is formed between the first heating element and the second heating element, a third heating area is formed in the inner cavity of the first heating element, the ammonia fuel can flow through the first heating zone, the second heating zone, and the third heating zone in sequence.

4. The ammonia-fueled fast pyrolysis staged injection gun of claim 3, wherein the heating tube includes a flared section in communication with the fuel inlet, the space in the first heating zone gradually increasing in a direction from the fuel inlet to the heating tube within the flared section.

5. The ammonia fuel fast pyrolysis staged injection gun according to claim 3, wherein the first heating element and the second heating element are both spiral electric heating wires, a filler is embedded in a gap between two adjacent circles of the electric heating wires, the filler and the electric heating wires are fixedly connected into a whole, the radial dimension of the inner wall of the filler is larger than that of the inner wall of the electric heating wires, and the radial dimension of the outer wall of the filler is smaller than that of the outer wall of the electric heating wires.

6. The ammonia-fueled staged fast pyrolysis injection gun according to claim 1, further comprising a transition pipe, wherein one end of the transition pipe is connected to the heating pipe, the other end of the transition pipe is connected to the injection assembly, the transition pipe comprises an inner pipe and an outer pipe, and a heat storage layer is filled between the inner pipe and the outer pipe.

7. The ammonia-fueled fast pyrolysis staged spray gun according to claim 1, wherein the spray assembly comprises a mounting member and a rotating shaft, the mounting member is connected with the heating tube, the rotating shaft is fixed on the mounting member, and each spray head is sleeved on one rotating shaft and is rotatably connected with the rotating shaft; the ammonia fuel fast pyrolysis graded injection gun further comprises a limiting assembly, the limiting assembly is connected with the injection assembly, and the limiting assembly is used for limiting the spray head at the current injection angle.

8. The ammonia fuel fast pyrolysis staged injection gun according to claim 7, wherein the limiting assembly comprises a limiting member detachably connected to the mounting member, and in a limiting state, the limiting member is fixedly connected to the mounting member and abuts against the nozzle to limit rotation of the nozzle; under the rotation state, the fixed relation of locating part with the installed part is relieved, just the locating part with the shower nozzle separation.

9. The ammonia fuel fast pyrolysis staged injection gun of claim 8, wherein the injection assembly further comprises guide members connected to the mounting member, guide grooves are defined between adjacent guide members, the nozzle head extends into the guide grooves and is attached to the groove walls of the guide grooves, and the attachment area is a cambered surface.

10. The ammonia fuel fast pyrolysis grading injection gun according to claim 1, wherein a partition plate is arranged inside the nozzle, a first injection cavity and a second injection cavity for injecting the ammonia fuel are respectively arranged on two sides of the partition plate, and a surface of the partition plate is provided with a protrusion.