AU2011373507B2

AU2011373507B2 - Burner nozzle and coal gasifier

Info

Publication number: AU2011373507B2
Application number: AU2011373507A
Authority: AU
Inventors: Zhen Wu
Original assignee: KEDA ANHUI CLEAN ENERGY CO Ltd
Current assignee: KEDA (ANHUI) CLEAN ENERGY Co Ltd
Priority date: 2011-07-15
Filing date: 2011-07-15
Publication date: 2015-10-08
Anticipated expiration: 2031-07-15
Also published as: AU2011373507A1; RU2014105562A; WO2013010304A1; RU2573072C2

Abstract

A burner nozzle and a coal gasifier. The burner nozzle comprises a nozzle housing (10). A fuel channel (20), a combustion-supporting gas channel (30), and a cooling channel (40) are disposed in the nozzle housing (10). A cooling cavity (50) is provided at a front end of the nozzle housing (10). A spiral pipeline (60) in communication with the cooling channel (40) is embedded in the cooling cavity (50), so as to form a spiral cooling flow passage. The spiral pipeline (60) embedded in the cooling cavity (50) forms the spiral cooling flow passage used as an independent pipeline, and therefore no angular connection with a wall surface of the nozzle housing (10) is required, so as to prevent cracking of the cooling cavity caused by a great temperature difference, uneven stress, and thermal fatigue at the connection corner, thereby improving the service life and reliability of the burner nozzle.

Description

Burner Nozzle and Coal Gasifier FIELD OF THE TECHNOLOGY [0001] The present invention relates to technology of combustion equipment structure, in particular relates to a burner nozzle and a coal gasifier. BACKGROUND [0002] A burner nozzle is a conventional combustion component, which is widely used in various combustion equipments such as engine, boiler, coal gasifier etc. [0003] A typical structure of the burner nozzle is shown in Fig. 1, the burner nozzle comprises a housing 10 with a substantially cylinder shape, a fuelpassage 20 and a combustion-supporting gaspassage 30 are disposed in the housing 10, the fuel which passes through the fuel passage 20 and the combustion-supporting gas which passes through the combustion-supporting gas passage 30 are mixed at an end of the burner nozzle, and are ignited to form flame. According to the gas compositions of different combustion-supporting gas, the burner nozzle are divided into three types, which are air combustion-supporting type, oxygen-enriched combustion-supporting type and pure oxygen combustion-supporting type. The oxygen content of the combustion-supporting gas in a nozzle of oxygen-enriched combustion-supporting type is above 20%, a nozzle of pure oxygen combustion-supporting type adopts combustion-supporting gas with oxygen content above 99%. [0004] As for the burner nozzle of above structure, the fuel and the combustion-supporting gas are jet out from the nozzle at the same time, and are ignited to form flame. There is an interval D between the flame and the front end of the nozzle, generally, the value of the interval D decreases as the oxygen content of the combustion-supporting gas increases and as the pressure in the hearth of the gasifier increases. Since the flame temperature is high (the temperature at the flame core is more than 2000'C). Even if we take the flame core temperature of 1500'C for calculating, it will still result in an unbearable temperature at the surface of the front end of the nozzle. This will affect both the service life and the working reliability of the nozzle. [0005] In order to overcome this defect, the prior art provides solutions refer to Chinese patent applications with application numbers 200620045550.6 and 88108098.5. In the technical scheme, the cooling cavity of the nozzle end is constructed by providing a wing rib of spiral shape. However, the technical scheme has the following defects: [0006] The wing rib is in bevel connection with the wall surface of the cooling cavity, whether they are integrated as one part or fixed by welding, there still exists problems of temperature

I

difference and nonuniform bearing stress between the position of the bevel connection and other positions, which will easily cause crack and damage. Once the cooling cavity of the wing rib structure is damaged, it is difficult to repair, an integral replacement of the nozzle end is needed. The cooling cavity of the wing rib structure is of poor working sealing and poor reliability, if the wing rib is crack and damaged, it will no longer guide the coolant to flow, even will result in that the coolant flows out of the nozzle, which affects the combustion. SUMMARY [0007] An embodiment of the present invention provides a burner nozzle and a coal gasifier, that may optimize the structure of the cooling cavity, and may reduce the damage due to nonuniform stress. [0008] A first aspect of the present invention provides a burner nozzle, comprising a nozzle housing which is provided with a fuel passage, a combustion-supporting gas passage and a cooling passage, a front end of the nozzle housing is provided with a cooling cavity, wherein: a spiral shaped pipeline, which is connected with the cooling passage, is embeddedly provided in the cooling cavity, such that to form a spiral shaped cooling passage; wherein: one or two end surface of the cooling cavity is formed with a groove, the shape of the groove matches the shape of the spiral shaped pipeline, such that to fasten the spiral shaped pipeline in the cooling cavity. [0009] The burner nozzle above has, preferably: a cross-section of the spiral shaped pipeline is of circle shape or oval shape. [0010] The burner nozzle above has, preferably: the cooling cavity is formed by fastening and welding a shroud to a wall surface of the front end of the burner nozzle. [0011] The burner nozzle above,: one or two end surface of the cooling cavity is formed with a groove, the shape of the groove matches the shape of the spiral shaped pipeline, such that to fasten the spiral shaped pipeline in the cooling cavity. [0012] The burner nozzle above has, preferably: one or two end surface of the cooling cavity is formed with multiple pins, the spiral shaped pipeline is fastened by winding between the pins. [0013] The burner nozzle above has, preferably: an end surface of the cooling cavity facing the outside of the burner nozzle is formed with multiple pins, the spiral shaped pipeline is fastened by winding between the pins; an end surface of the cooling cavity facing the inside of the burner nozzle is formed with a groove, the shape of the groove matches the shape of the spiral shaped pipeline, such that to fasten the spiral shaped pipeline in the cooling cavity. [0014] The burner nozzle above has, preferably: a flow guiding pipe is formed in the cooling passage, the flow guiding pipe is butt joined with the spiral shaped pipeline. 2 [0015] The burner nozzle above has, preferably: a cross-section of the cooling passage is annular, the flow guiding pipe is spirallywinded in the cooling passage. [0016] The burner nozzle above has, preferably: the spirally winded flow guiding pipe is provided in a partial passage of the cooling passage which is supplied with coolant. [0017] The burner nozzle above has, preferably: the cooling passage is respectively communicated with the spiral shaped pipeline and the cooling cavity apart from the spiral shaped pipeline. [0018] The burner nozzle above has, preferably: there are at least two cooling passages, at least one of which is communicated with the spiral shaped pipeline, at least one of which is communicated with the cooling cavity apart from the spiral shaped pipeline. [0019] The above burner nozzle, preferably: the spiral shaped pipeline is copper pipe, carbon steel pipe or stainless steel pipe. [0020] The burner nozzle above has, preferably: the fuel passage is provided along a longitudinal central axis of the burner nozzle, the combustion-supporting gas passage surrounds the outside of the fuel passage, the cooling passage surrounds the outside of the combustion-supporting gas passage. [0021] The burner nozzle above has, preferably: the cooling passage configured to supply the coolant and the cooling passage configured to backflow the coolant are both provided at a same side of the housing. [0022] Another aspect of the present invention further provides a coal gasifier, comprising the burner nozzle of the first aspect. [0023] The burner nozzle and the coal gasifier provided by an embodiment of the present invention, through embeddedly providing the spiral shaped pipeline in the cooling cavity to form the spiral shaped cooling flow passage, such that the spiral shaped cooling passage is an independent pipeline, which can avoid forming a bevel connection between the spiral shaped cooling passage and the wall surface of the burner nozzle, which may thus prevent the crack of the cooling cavity due to large temperature difference at the bevel position, the nonuniform stress and thermal fatigue. The technical scheme of an embodiment of the present invention may optimize the structure of the cooling cavity of the burner nozzle, reduces the probability of metal fatigue damage, and increases the service life and the working reliability of the burner nozzle. BRIEF DESCRIPTION OF THE DRAWINGS [0024] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying non-limiting drawings, in which: 3 [0025] Fig. 1 is a schematic structural diagram of a typical burner nozzle of prior art; [0026] Fig. 2A is a schematic structural diagram of a burner nozzle provided by Embodiment One of the present invention; [0027] Fig. 2B is a sectional-view schematic diagram along A-A direction of Fig. 2A; [0028] Fig. 3A is a schematic structural diagram of a burner nozzle provided by Embodiment Two of the present invention; [0029] Fig. 3B is a sectional-view schematic diagram along B-B direction of Fig. 3A; [0030] Fig. 3C is a sectional-view schematic diagram along C-C direction of Fig. 3A; [0031] Fig. 4 is a schematic partial structural diagram of a burner nozzle provided by Embodiment Three of the present invention; [0032] Fig. 5 is a schematic partial structural diagram of a burner nozzle provided by Embodiment Four of the present invention; [0033] Fig. 6 is a schematic partial structural diagram of a burner nozzle provided by Embodiment Five of the present invention; [0034] Fig. 7 is a schematic partial structural diagram of a burner nozzle provided by Embodiment Six of the present invention; [0035] Fig. 8 is a schematic partial structural diagram of a burner nozzle provided by Embodiment Seven of the present invention. DETAILED DESCRIPTION [0036] In order to make the purposes, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described more clearly and completely in combination with the drawings of the embodiments of the present invention. Obviously, the embodiments described here are a part of the embodiments of the present invention but not all of the embodiments. Based on the embodiments of the present invention, all of other embodiments obtained by those skilled in the art without creative work are within the protection scope of the present invention. [0037] Embodiment One [0038] Fig. 2A is a schematic structural diagram of a burner nozzle provided by Embodiment One of the present invention, Fig. 2B is a sectional-view schematic diagram along A-A direction of Fig. 2A, the burner nozzle comprises a burner housing 10 which is provided with a fuel passage 20, a combustion-supporting gas passage 30 and a cooling passage 40, a front end of the nozzle housing 10 is provided with a cooling cavity 50, wherein, a spiral shaped pipeline 60, which is connected with the cooling passage 40, is embeddedly provided in the cooling cavity 4 50, such that to form a spiral shaped cooling passage. [0039] The present embodiment is a preferable structure, the fuel passage 20 is provided along a longitudinal central axis of the burner nozzle 10, the combustion-supporting gas passage 30 is around the outside of the fuel passage 20, the cooling passage 40 can be provided outside of the combustion-supporting gas passage 30. In addition, the cooling passages 40 preferably configured to supply and backflow the coolant are both provided at a same side of the housing 10, and are respectively communicated with the inlet and the outlet of the spiral shaped pipeline 60, as shown in Fig. 2A and Fig. 2B, Fig. 2B shows the position of the coolant inlet and the coolant outlet of the spiral shaped pipeline 60. A central part of the spiral shaped pipeline 60 can be reserved for the outlet of the fuel passage 20 and the combustion-supporting gas passage 30. The fuel passage 20 and the cooling passage 40 are substantially cylinders, the cross section of the combustion-supporting gas passage 30 is of a substantially annular. However, in practical application, the relative position relationship between the fuel passage 20, the combustion-supporting gas passage 30 and the cooling passage 40, the shape of the cross section and the shape of the longitudinal axis of each passage are not limited to Fig. 2A and Fig. 2B, each passage can be arranged according to practical needs if it can guide corresponding fluid to flow. [0040] The burner nozzle provided by the present embodiment, through embeddedly providing the spiral shaped pipeline in the cooling cavity to form the spiral shaped cooling flow passage, such that the spiral shaped cooling passage is an independent pipeline, which avoids from forming a bevel connection between the spiral shaped cooling passage and the wall surface of the burner nozzle, thus preventing the crack of the cooling cavity due to large temperature difference at the bevel position and the nonuniform stress. The technical scheme optimizes the structure of the cooling cavity of the burner nozzle, reduces the probability of damage, and increase the working reliability of the burner nozzle. [0041] In the present embodiment, preferably, two container cavities for coolant are respectively formed inside and outside of the spiral shaped pipeline. The cooling passage can respectively communicated with the cooling cavities inside and outside the spiral shaped pipeline, both the inside and outside container cavities have flowing coolant inside the cavity. Such a design is beneficial that, a uniform flow of the coolant at the front end of the nozzle is guaranteed through the spiral shaped pipeline, which achieves a good cooling effect, the two-layer container cavities guarantee the working reliability of the nozzle, the inside and outside container cavities achieve heat exchange through the spiral shaped pipeline, the temperature is substantially the same, even if the spiral shaped pipeline is damaged, the coolant 5 will not escape from the nozzle and thus will not affect the combustion. The cooling cavity outside the spiral shaped pipeline constitutes a cooling system outside the pipe, which means to form a heat resisting protection on the surface of the nozzle shroud. [0042] There can be multiple manners by which the spiral shaped pipeline 60 is fixed in the cooling cavity 50, such as in the present embodiment, the cooling cavity 50 can be formed by fastening the shroud 70 to the wall surface of the front end of the nozzle housing 10, or can be formed by welding fastening, then the spiral shaped pipeline 60 can be fastened in the cooling cavity 50 by the shroud 70. Or the spiral shaped pipeline can be welding fixed on the wall surface of the front end of the nozzle housing. Other fixing manners will be described in the following embodiment. [0043] No matter what kind of manner is adopted, since the spiral shaped pipeline is an independent pipe, all of the manners can avoid the spiral shaped pipeline from being bevel connected with the wall surface of the housing, which solves the problem of nonuniform stress. The cross section of the spiral shaped pipeline is preferably of a circle shape or oval shape, the pipeline of substantially cylinder shape can avoid a bevel connection effectively. [0044] The technical scheme of the present embodiment further has the advantages of low production cost and maintenance cost. The independent spiral shaped pipeline embeddedly provided in the cooling cavity can be removed and replaced directly, it is unnecessary to refit the whole burner nozzle, thus there is no need to stop using the burner nozzle for a long period of time. [0045] Embodiment Two [0046] Fig. 3A is a schematic structural diagram of a burner nozzle provided by Embodiment Two of the present invention, Fig. 3B is a sectional-view schematic diagram along B-B direction of Fig. 3A, Fig. 3C is a sectional-view schematic diagram along C-C direction of Fig. 3A. The difference between the present embodiment and Embodiment One is: there are two cooling passages 40 provided in the housing 10, one of which is communicated with the spiral shaped pipeline 60, another cooling passage 40 is communicated with the cooling cavity 50 apart from the spiral shaped pipeline 60, as shown in Fig. 3A, 3B and 3C, which respectively set the inlet and the outlet of two cooling passage 40. The cooling passages 40 comprising the supply passage and the backflow passage are respectively provided at the two sides of the housing 10. [0047] In the present embodiment, the cooling cavity is divided into two spiral shaped cooling passages by the spiral shaped pipeline, and both of which are supplied with coolant by an cooling passage independently, which can further improve the cooling effect. [0048] In specific application, the number of the cooling passage are not limited to 2, there can 6 be at least two cooling passages, at least one of which is communicated with the spiral shaped pipeline, at least one of which is communicated with the cooling cavity apart from the spiral shaped pipeline. One or more group of coolant inlets and coolant outlets can be provided on the spiral shaped pipeline and the cooling cavity, such that to connect the corresponding cooling passage. The number of the spiral shaped pipeline are also not limited to 1, there can be multiple spiral shaped pipelines, which connect with a single cooling passage, or respectively connect with multiple cooling passages. [0049] Embodiment Three [0050] Fig. 4 is a schematic partial structural diagram of a burner nozzle provided by Embodiment Three of the present invention, the present embodiment can be based on the technical scheme of each embodiment above, a groove 51 can be formed on one or two end surfaces of the cooling cavity 50, generally, formed on the wall surface of the front end of the nozzle housing 10 and on the shroud 70, the shape of the groove 51 matches the shape of the spiral shaped pipeline, which fastens the spiral shaped pipeline in the cooling cavity 50. [0051] The manner for fixing the spiral shaped pipeline provided by the present embodiment can further reduce the dot connection or linear connection between the spiral shaped pipeline and the wall surface of the housing, increse the contact area between the spiral shaped pipeline and the housing, which not only improves the conduction cooling performance, but also avoids the damage and breakage at the rigid connection position due to nonuniform stress. [0052] In addition, each embodiment above adopts independent pipeline to form the cooling passage, which actually forms two container cavities of the coolant liquid at the inside and outside of the spiral shaped pipeline. [0053] In each embodiment of the present invention, the spiral shaped pipeline is preferably copper pipe, carbon steel pipe or stainless steel pipe etc, or can be prepared by other materials with good conduction performance, such that to improve the heat transfer effect of the coolant inside and outside the spiral shaped pipeline. [0054] Embodiment Four [0055] Fig. 5 is a schematic partial structural diagram of a burner nozzle provided by Embodiment Four of the present invention, the present embodiment can be based on the technical scheme of each embodiment above, which provides another scheme of fixing the spiral shaped pipeline 60. In the present embodiment, one or two end surfaces of the cooling cavity 50 are formed with multiple pins 52, the pins 52 are provided facing the inside of the cooling cavity 50, which can be substantially perpendicular to the wall surface of the front end of the housing 10, the spiral shaped pipeline 60 is fixed by winding between the pins 52. 7 [0056] The technical scheme of the present embodiment also avoids a direct rigid connection between the spiral shaped pipeline and the wall surface of the housing, such that to reduce the possibility of damage, and facilitate the installation and remove. [0057] Embodiment Five [0058] Fig. 6 is a schematic partial structural diagram of a burner nozzle provided by Embodiment Five of the present invention, more preferably, combining the technical means of Embodiment Three and Embodiment Four, the end surface of the cooling cavity 50 facing the outside of the burner nozzle is formed with multiple pins 52, the pins 52 are provided facing the inside of the cooling cavity 50, the pins 52 are generally formed on the shroud 70, the spiral shaped pipeline is fastened by winding between the pins 52. The end surface of the cooling cavity 50 facing the inside of the burner nozzle is formed with a groove 51, generally formed on the wall surface of the front end of the burner nozzle 10, the shape of the groove 51 matches the shape of the spiral shaped pipeline, such that to fasten the spiral shaped pipeline in the cooling cavity. 50 [0059] The above technical scheme facilitates processing and manufacturing, the shroud of the burner nozzle can be designed as a flat shape, the pins are welded inward. [0060] Embodiment Six [0061] Fig. 7 is a schematic partial structural diagram of a burner nozzle provided by Embodiment Six of the present invention, the present embodiment can be based on the technical scheme of each embodiment above, which further optimizes the structure of the cooling passage 40. In the present embodiment, a guiding pipe 80 is formed in the cooling passage 40, the flow guiding pipe 80 is butt joined with the spiral shaped pipeline 60, that is, the flow guiding pipe 80 is sealed communicated with the pipe opening of the spiral shaped pipeline 60, but is not communicated with the cooling cavity 50 apart from the spiral shaped pipeline 60. [0062] The technical scheme of the present embodiment provides an independent guiding pipe for the spiral shaped pipeline, the guiding pipe directly supplies coolant for the spiral shaped pipeline. The cooling passage outside the guiding pipe can have coolant or not, that is, the outside of the spiral shaped pipeline can be either provided with coolant or not. [0063] Embodiment Seven [0064] Fig. 8 is a schematic partial structural diagram of a burner nozzle provided by Embodiment Seven of the present invention, the present embodiment can be based on Embodiment Six, the cross section of the cooling passage 40 is of an annular, the guiding pipe 80 is spirally winded in the cooling passage 40. Preferably only provided in partial passage of the cooling passage 40 which is supplied with coolant. 8 [0065] The guiding pipe 80 is butt joined with the inlet of the spiral shaped pipeline 60, that is, the guiding pipe 80 is in sealed communication with the inlet of the spiral shaped pipeline 60, the outlet of the spiral shaped pipeline 60 is communicated with another cooling passage 40. [0066] In Embodiment Six above, the cooling passage can be of tubular shape, which is only provided at one side of the housing, or the cooling passage can be a passage with its cross section of annular shape, which is around the outside of the combustion-supporting gas passage. In the present Embodiment Seven, the cooling passage is specifically a passage with its cross section of annular shape, which is around the outside of the combustion-supporting gas passage, the guiding pipe is winded in the cooling passage, which guarantees a sufficient heat transfer of the coolant inside and outside the cooling cavity. [0067] The embodiment of the present invention further provides a coal gasifier, which comprises the burner nozzle provided by any embodiment of the present invention. The coal gasifier, through embeddedly providing the spiral shaped pipeline in the cooling cavity to form the spiral shaped cooling flow passage, such that the spiral shaped cooling passage is an independent pipeline, which avoids from forming a bevel connection between the spiral shaped cooling passage and the wall surface of the burner nozzle, thus preventing the crack of the cooling cavity due to large temperature difference at the bevel position and the nonuniform stress. The technical scheme optimizes the structure of the cooling cavity of the burner nozzle, reduces the probability of damage, and increase the working reliability of the burner nozzle. [0068] Finally, it should be noted that the above embodiments are merely provided for describing the technical solutions of the present invention, but not intended to limit the present invention. It should be understood by those of ordinary skill in the art that although the present invention has been described in detail with reference to the foregoing embodiments, modifications can be made to the technical solutions described in the foregoing embodiments, or equivalent replacements can be made to some technical features in the technical solutions, as long as such modifications or replacements do not cause the essence of corresponding technical solutions to depart from the scope of the present invention. [0069] In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. [0070] It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common 9 general knowledge in the art, in Australia or any other country. 10

Claims

1. A burner nozzle, comprising a nozzle housing which is provided with a fuel passage, a combustion-supporting gas passage and a cooling passage, a front end of the nozzle housing is provided with a cooling cavity, wherein: a spiral shaped pipeline, which is connected with the cooling passage, is embeddedly provided in the cooling cavity, such that to form a spiral shaped cooling passage; wherein one or two end surface of the cooling cavity is formed with a groove, the shape of the groove matches the shape of the spiral shaped pipeline, such that to fasten the spiral shaped pipeline in the cooling cavity.

2. The burner nozzle according to claim 1, wherein: a cross-section of the spiral shaped pipeline is of circle shape or oval shape.

3. The burner nozzle according to claim 1 or 2, wherein: the cooling cavity is formed by fastening and welding a shroud to a wall surface of the front end of the burner nozzle.

4. The burner nozzle according to any one of claims 1 to 3, wherein: one or two end surface of the cooling cavity is formed with multiple pins, the spiral shaped pipeline is fastened by winding between the pins.

5. The burner nozzle according to any one of claims 1 to 3, wherein: an end surface of the cooling cavity facing the outside of the burner nozzle is formed with multiple pins, the spiral shaped pipeline is fastened by winding between the pins; and an end surface of the cooling cavity facing the inside of the burner nozzle is formed with a groove, the shape of the groove matches the shape of the spiral shaped pipeline, such that to fasten the spiral shaped pipeline in the cooling cavity.

6. The burner nozzle according to any one of claims 1 to 5, wherein: a flow guiding pipe is formed in the cooling passage, the flow guiding pipe is butt joined with the spiral shaped pipeline.

7. The burner nozzle according to claim 6, wherein: a cross-section of the cooling passage is annular, the flow guiding pipe is spirally winded in the cooling passage.

8. The burner nozzle according to claim 7, wherein: the spirally winded flow guiding pipe is provided in a partial passage of the cooling passage which is supplied with coolant.

9. The burner nozzle according to any one of claims 1 to 8, wherein: the cooling passage is respectively communicated with the spiral shaped pipeline and the cooling cavity apart from the spiral shaped pipeline.

10. The burner nozzle according to any one of claims 1 to 9, wherein: there are at least two cooling passages, at least one of which is communicated with the spiral shaped pipeline, at 11 least one of which is communicated with the cooling cavity apart from the spiral shaped pipeline.

11. The burner nozzle according to any one of claims I to 10, wherein: the spiral shaped pipeline is copper pipe, carbon steel pipe or stainless steel pipe.

12. The burner nozzle according to any one of claims 1 to 11, wherein: the fuel passage is provided along a longitudinal central axis of the burner nozzle, the combustion-supporting gas passage surrounds the outside of the fuel passage, the cooling passage surrounds the outside of the combustion-supporting gas passage.

13. The burner nozzle according to claim 12, wherein: the cooling passage configured to supply the coolant and the cooling passage configured to backflow the coolant are both provided at a same side of the housing.

14. A coal gasifier, comprising the burner nozzle according to any one of claims 1-13. 12