Combustor

Abstract

A combustor comprising: a first channel surrounding a centerline and terminating in a first end; a second channel surrounding the first channel and terminating in a second end, the second channel including a convergent tapered section forming a first angle with respect to the centerline; a third channel surrounding the second channel and terminating in a third end, the third channel including a convergent tapered section forming a second angle with respect to the centerline; wherein the third end includes one or more slots.

Description

Technical Field

[0001] The present invention generally relates to burners, particularly to burners for gasification systems, and more particularly to advanced devices for injecting feed into a gasifier. Background Art

[0002] At least some known gasifiers convert a mixture of fuel, air or oxygen, liquid water and / or steam, and / or flux and / or auxiliary additives into an output of partially oxidized gas, which is commonly referred to as "synthesis gas" or "syngas". The partial oxidation or gasification of solid carbonaceous fuels such as coal to produce a gas that has value as a residential and industrial fuel, as a starting material for the synthesis of chemicals and fuels, and as an energy source for generating electricity has long been recognized and practiced on various scales throughout the world.

[0003] Fuel, air or oxygen, liquid water and / or steam, and / or flux or auxiliary additives are injected into the gasifier through a feed injector from separate sources, and the feed injector connects the sources of the feed components to a feed nozzle. The feed components individually traverse the feed injector and are combined in a reaction zone downstream of the nozzle. In order for the reaction to be completed within a short time while the feed is in the reaction zone, the feed components need to be in intimate mixing. At least some known gasification feed injectors are designed to inject the feed components into the reaction zone at high speed to promote atomization, however such methods reduce the available reaction time and tend to inhibit efficient conversion. Summary of the Invention

[0004] An object of the present invention is to provide a burner that can provide more available reaction time and promote efficient conversion of the feed.

[0005] The following outlines several technical solutions of the burner according to the present invention.

[0006] Technical Solution 1. A burner, comprising:

[0007] A first channel that surrounds a centerline and terminates in a first end;

[0008] A second channel that surrounds the first channel and terminates in a second end, the second channel including a converging conical section that forms a first angle relative to the centerline;

[0009] A third channel that surrounds the second channel and terminates in a third end, the third channel including a converging conical section that forms a second angle relative to the centerline;

[0010] wherein the third end includes one or more slots.

[0011] Technical solution 2. The burner of technical solution 1, wherein the first channel includes a section with a constant cross-sectional area terminating at a first end.

[0012] Technical solution 3. The burner of technical solution 1, wherein one or more slots have a swirl angle less than or equal to 15 degrees.

[0013] Technical solution 4. The burner of technical solution 1, wherein the first angle is in the range of 10 to 50 degrees.

[0014] Technical solution 5. The burner of technical solution 1, wherein the value of the second angle minus the first angle is in the range of 0 to 10 degrees.

[0015] Compared with the prior art, the burner according to the present invention has one or more slots in the third end, which can provide more available reaction time and promote the effective conversion of the feed. Description of the Drawings

[0016] The present invention will be described hereinafter in conjunction with the drawings, wherein like reference numerals represent like elements:

[0017] Figure 1 is a schematic cross-sectional side view of a burner according to one or more aspects of the present disclosure.

[0018] Figure 2A is a schematic view of the front part of the end of a burner according to one or more aspects of the present disclosure.

[0019] Figure 2B is Figure 2A a schematic view of a variant thereof, wherein the burner end has one or more tapered slots.

[0020] Figure 2C is Figure 2A a schematic view of a variant thereof, wherein the burner end has one or more tapered slots with a swirl angle. Detailed Description

[0021] The following detailed description provides only preferred exemplary embodiments and is not intended to limit the scope, applicability, or construction of the present invention. On the contrary, the following detailed description of the preferred exemplary embodiments will provide those skilled in the art with an enabling description for implementing the preferred exemplary embodiments of the present invention. Various changes can be made in the function and arrangement of the elements without departing from the spirit and scope of the present invention.

[0022] As used herein, the articles "a" or "an" when applied to any feature of the embodiments of the invention described in the specification mean one or more. The use of "a" and "an" does not limit the meaning to a single feature unless such a limitation is specifically stated. The article "the" before a singular or plural noun or noun phrase denotes one or more specifically specified features and may have a singular or plural meaning depending on the context in which it is used.

[0023] The phrase "and / or" placed between a first entity and a second entity includes any of the following meanings: (1) only the first entity, (2) only the second entity, or (3) the first entity and the second entity. The phrase "and / or" placed between the last two entities of a list of three or more entities means at least one of the entities in the list, including any particular combination of the entities in the list. For example, "A, B and / or C" has the same meaning as "A and / or B and / or C" and includes the following combinations of A, B and C: (1) only A, (2) only B, (3) only C, (4) A and B but not C, (5) A and C but not B, (6) B and C but not A, and (7) A and B and C.

[0024] The adjective "any" means one, some or all without selection of quantity.

[0025] The phrase "at least a portion" means "a portion or all". "At least a portion of a stream" has the same composition as the stream from which it is derived, with the concentration of each species in the material being the same.

[0026] As used herein, "first", "second", "third", etc. are used to distinguish multiple steps and / or features and do not denote a total number or relative position in time / or space unless expressly stated to be so.

[0027] "Downstream" and "upstream" refer to the intended flow direction of the process fluid being conveyed. If the intended flow direction of the process fluid is from a first device to a second device, the second device is downstream of the first device. In the case of a circulating flow, downstream and upstream refer to the first pass of the process fluid.

[0028] Figure 1A schematic side cross-sectional view of burner 1 in accordance with one or more aspects of the present disclosure. The first channel 10 may be configured to deliver a carbonaceous fuel to a gasifier (not shown) via a first end 12. In some embodiments, the carbonaceous fuel may be pulverized coal suspended in a carrier gas. The first channel 10 may be symmetric about a centerline 14 and may be straight and non-tapering, in other words, the cross-sectional area of the first channel 10 is constant. The straight and non-tapering first channel may reduce turbulence and erosion caused by coal particles impacting on the walls of the first channel 10. The second channel 16 may concentrically surround the first channel 10 and may be configured to deliver an oxidant via an oxidant inlet 18, such as oxygen, an oxygen-steam mixture, or an oxygen-enriched gas. The second channel 16 may be configured to deliver the oxidant at a first angle A with respect to the centerline 14 via a second end 20 so as to improve mixing and atomization of the carbonaceous fuel, which may shorten the flame length and ensure complete reaction. Especially in a side-fired gasifier, shortening the flame length may improve operation by preventing the flame from impinging on the opposite wall. A longer flame may also cause overheating in the burner. The first angle A may be in the range of 10 to 50 degrees or 20 to 45 degrees. The third channel 22 may concentrically surround the second channel 16 and may be configured to deliver an inert gas, such as carbon dioxide, nitrogen, steam, or a mixture thereof, via an inert inlet 24. The thickness of the third channel 22 may be greater than 1 mm. The inert gas may be delivered at a speed greater than or equal to 5 m / s under all operating conditions. The third channel 22 may be configured to deliver the inert gas at a second angle B with respect to the centerline 14 via a third end 26. The second angle B may be in the range of 10 degrees to 60 degrees or 30 to 60 degrees. The value of the second angle B minus the first angle A may be in the range of 0 to 10 degrees.

[0029] The cooling jacket 30 may surround the third channel 22 to protect the interior of the burner (defined as the first channel 10, the second channel 16, and the third channel 22) from the high temperatures generated in the gasifier. A coolant, such as water, may be delivered into the cooling jacket via a coolant inlet 32 and discharged via a coolant outlet 34. The coolant may be supplied at a pressure higher than the pressure of the gasifier, for example, at a pressure 10 bar higher than the pressure of the gasifier. The thin-walled front portion 36 facing the gasifier may have a thickness in the range of 1.5 to 5 mm. The thin-walled front portion 36 may be made of a high-temperature high-strength alloy with corrosion resistance, such as a high-nickel alloy including alloy 718 or alloy 188. The inner edge 38 of the thin-walled front portion 36 may be rounded to reduce thermal stress.

[0030] The interior of the burner and the cooling jacket may be configured as a removable burner head, which is connected to a burner body including pipes and flanges (not shown) via a burner connector (not shown). The burner connector may include an internally removable connector and an externally removable connector. The burner connector may include a single connector.

[0031] Figure 2A Schematic view of the front part of the burner tip according to one or more aspects of the present disclosure. The second tip 20 is visible behind the third tip 26. The first channel 10 is visible in the center of the burner. Figure 2B is Figure 2A Schematic view of a variant of, in which the third tip 26 has one or more tapered slots 40. As Figure 2A shown, the one or more tapered slots 40 can be rectangular sections removed from the third tip 26, or can be any other shape that provides a shorter path for a portion of the flow in the third channel to exit the burner. The one or more tapered slots 40 can allow a reduction in the flow rate of the inert gas required to maintain a sufficient gas velocity. The one or more tapered slots 40 can also reduce the risk of blockage of the third channel. The one or more tapered slots 40 can provide a clearance size of at least 2 mm. Figure 2C is Figure 2A Schematic view of a variant of, in which the third tip 26 has one or more tapered slots 40, which have a swirl angle C relative to a line drawn radially from the center of the burner. The swirl angle C can be less than 15 degrees, or can be in the range of 0 degrees to 15 degrees. The swirl angle C can improve the shielding effect of the inert gas and can also improve the mixing in the flame. Tapered slots may not be required in the second tip 20 because there is typically a greater oxidant flow than the inert gas, and placing the tapered slots in the second tip 20 at a swirl angle can increase the mixing of oxygen and fuel such that the flame is generated too close to the front of the burner and produces an excessive heat flux on the burner. Conversely, when the flow rate of the inert gas through the third channel 22 is low, increasing the mixing through the tapered slots 40 in the third tip 26 can be advantageous. In applications where the flow rate of the inert gas through the third channel 22 is high, such as when using high calorific value fuels (such as anthracite and petroleum coke), tapered slots may not be required.

[0032] Accordingly, the present disclosure can provide a system for delivering a carbonaceous fuel to a gasifier. The system can include any of the various features disclosed herein, including one or more of the following aspects.

[0033] Aspect 1: A burner, comprising: a first channel that surrounds a centerline and terminates in a first tip; a second channel that surrounds the first channel and terminates in a second tip, the second channel including a converging tapered section that forms a first angle relative to the centerline; a third channel that surrounds the second channel and terminates in a third tip, the third channel including a converging tapered section that forms a second angle relative to the centerline; wherein the third tip includes one or more slots.

[0034] Aspect 2: The burner according to aspect 1, wherein the first channel includes a section of constant cross-sectional area that terminates at the first tip.

[0035] Aspect 3: The burner according to Aspect 1 or Aspect 2, wherein one or more slots have a swirl angle less than or equal to 15 degrees.

[0036] Aspect 4: The burner according to any one of Aspects 1 to 3, wherein the first angle is in the range of 10 to 50 degrees.

[0037] Aspect 5: The burner according to any one of Aspects 1 to 4, wherein the value of the second angle minus the first angle is in the range of 0 to 10 degrees.

[0038] Although the principles of the present invention have been described above in connection with preferred embodiments, it should be clearly understood that the description is by way of example only and is not intended as a limitation on the scope of the present invention.

Claims

1. A burner, the burner comprising: a first channel that surrounds a centerline and terminates in a first end; a second channel that surrounds the first channel and terminates in a second end, the second channel including a converging conical section that forms a first angle relative to the centerline; a third channel that surrounds the second channel and terminates in a third end, the third channel including a converging conical section that forms a second angle relative to the centerline; characterized in that the third end includes one or more slots.

2. The burner according to claim 1, wherein, The first channel includes a section of constant cross-sectional area that terminates at the first end.

3. The burner according to claim 1, wherein, The one or more slots have a swirl angle less than or equal to 15 degrees.

4. The burner according to claim 1, wherein, The first angle is in the range of 10 to 50 degrees.

5. The burner according to claim 1, wherein, The value of the second angle minus the first angle is in the range of 0 to 10 degrees.

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