Description:

TECHNICAL FIELD
[0001] The present invention, in general relates to a gas firing nozzle design for gas firing burners. More particularly, the invention related to gaseous fuel firing nozzle where shorter flame length is preferred with lower NOx generation in gaseous fuel fired boiler applications.
BACKGROUND
[0002] Background description includes information that may be useful in understanding the present invention.
[0003] For wall burner design fuel nozzle design plays key role in its interaction with combustion air, complete combustion and NOx generation during combustion. There are several types of fuel nozzles that have been developed for firing various gaseous, for e.g. solid and liquid fuels. Gaseous fuel firing in process industries involves a very complex mechanism, as the gaseous fuel composition varies significantly from conventional fuels such as natural gas or Liquefied Petroleum Gas (LPG).
[0004] The industrial gaseous fuels are refinery gas, low calorific value gases such as synthesis gas or blast furnace gas or coke oven gas are byproducts (off-gases) from the various furnaces used in the refining processes of industrial steel mills or refineries. Selection of fuel nozzles are used in the burner for combustion depends upon the type of fuel, its composition and available pressure of fuel. Multiple of such burners are used produce steam and/or power as per the requirement.
[0005] Therefore, the present novel invention of nozzle design describes about the various gaseous fuel firing nozzles for different fuel applications which will produce shorter flame, lower CO and NOx generation during combustion process.
[0006] To solve the above mentioned problems, US 20150226421 A1 describes gas turbine combustion system with reduced size and lower complexity and also maintaining the same NOx levels. In this invention the nozzles were arranged for injection of compressed air, however specific design was mentioned and only arrangement of air nozzles was discussed.
[0007] A cited prior art bearing the Indian Patent Application No 201831018466 describes an oil and gaseous fuel device developed for boiler applications where the device has capability of efficient fuel firing with minimal pollutant emission. In this invention a fuel nozzle has been mentioned where gaseous fuel is ejecting straight from the nozzle tip and side holes are arranged only on one side of the nozzle.
[0008] Another cited prior art EP0905443A2 describes a dual-fuel nozzle for a gas turbine combustor for firing liquid and gaseous fuels, wherein the liquid fuel nozzle and gaseous fuel nozzle forming an integrated structure within the flow passage. The gas release arrangement is through a convergent section at the nozzle tip.
[0009] Yet another prior art WO2005/031142A1 describes a directly injected gaseous fuel into combustion chamber of an internal combustion engine, wherein the compressed gaseous fuel is injected through nozzle at sonic velocity into combustion chamber. In this invention specific design for gaseous fuel is not discussed where the gaseous fuel injected at more than 10 MPa.
[0010] Also, a prior art US2019/0351370A1 describes a nozzle lance for treatment of exhaust gas. In the design of gaseous fuel lance is used to atomization of an active fluid by means of pressurized gas for exhaust gas treatment. In this nozzle lance design arrangement, gas feed lines were made to mix with active fluid in a mixing zone after which atomization zone is made. The design of lance nozzle is very different and it is for atomizing liquid active fluid, and
[0011] The prior art US2012/0137695A1 describes a fuel nozzle related to gas turbine engine. The fuel nozzle includes a gas only insert tip positioned on the tube. The gas nozzle tip is designed with plurality of vanes positioned on its tip and the tip end comprises a tip aperture and a plug is positioned with the tip aperture such that the breather hole positioned within the plug.
[0012] Although many gas nozzle or ejector concepts are available in the above mentioned prior arts for atomizing liquids and gases but the present invention significantly deviate from others in terms of number of arrangement of nozzle ports, simplicity in the design and fabrication. In the present invention, different variants of gas ejectors are designed for firing various type of gaseous fuel commonly found in refineries, steel plant, etc. which reduces the flame length and emits lower NOx.
OBJECTS OF THE DISCLOSURE
[0013] Some of the objects of the present disclosure, which at least one embodiment herein satisfy, are listed hereinbelow.
[0014] It is a general object of the present disclosure is to propose a gas nozzle design for various pressure conditions existing in the gas fired boilers with different calorific value of fuels.
[0015] It is another object of the present disclosure is to produce shorter flame length with lower NOx generation.
[0016] It is another object of the present disclosure is to provide low pressure drop when header gas pressure is less and to produce shorter flame lengths.
[0017] It is yet another object of the present disclosure is to use gas nozzle design in dual or multi-fuel firing boilers where gaseous fuel one of the fuel component.
[0018] These and other objects and advantages of the present invention will be apparent to those skilled in the art after a consideration of the following detailed description taken in conjunction with the accompanying drawings in which a preferred form of the present invention is illustrated.
SUMMARY
[0019] This summary is provided to introduce concepts related to provide gaseous fuel fired ejector design concepts in a burner. The concepts are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
[0020] In an embodiment, the present disclosure relates to a gaseous fuel fired nozzle designs have been provided for used in the wall mounted burner of a gaseous fuel fired furnace or boiler. Where the burner is a single fuel or multi-fuel fired assembly. The burner is also a single in number or multiple in number.
[0021] In an aspect, a gaseous fuel nozzle for injecting the gaseous fuel into furnace where it effectively mixes the surrounding air and it is capable of producing a stable flame, low Carbon Monoxide (CO) generation and low Nitrogen Oxides (NOx) generation. Where the gaseous fuel is admitted centrally and it is emitting into the combustion environment at an angle through the outer periphery of gaseous fuel nozzle tip. The angle at which it is existing the gaseous nozzle is depending upon the gaseous fuel type, gaseous fuel composition and pressure and temperature at which the it is available.
[0022] In an aspect, for gaseous fuel available at lower calorific value the higher number of gas emitting ports are envisaged and the gas nozzle tip header diameter is large.
[0023] In an aspect, for gaseous fuel available at lower pressure and it demands higher gaseous fuel input, in that case, many number of gas emitting ports are arranged in a lengthy gas nozzle tip in multiple rows.
[0024] In an aspect, wherein the number of gas emitting ports varies from 4 to 30 based demand of fuel firing.
[0025] In aspect, the angle of holes from centreline of horizontal axis varies from 100 to 800.
[0026] In aspect, the diameter of the gas nozzle tip also varies from 2 mm to 20 mm.
[0027] In another aspect, the fuel ejector tip designs can be used either in gaseous fuel firing burner alone or multi-fuel firing burners along with other fuels.
[0028] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.
[0029] It is to be understood that the aspects and embodiments of the disclosure described above may be used in combination with each other based on the requirement. Several of the aspects and embodiments may be combined to form a further embodiment of the disclosure.
[0030] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and, together with the description, serve to explain the disclosed principles. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system and/or methods in accordance with embodiments of the present subject matter are now described, by way of example only, and with reference to the accompanying figures, in which:
[0032] FIG. 1 illustrate gas nozzle design variant F viewed from top according to the invention.
[0033] FIG. 2 illustrates A-A view of Figure 1 with cross sectional view of the gas nozzle.
[0034] FIG. 3 illustrates gas nozzle design variant G viewed from top according to the invention.
[0035] FIG. 4 illustrate B-B view of Figure 3 with cross sectional view of the gas nozzle.
[0036] FIG. 5 illustrates gas nozzle design variant H viewed from top according to the invention.
[0037] FIG. 6 illustrates C-C view of Figure 5 with cross sectional view of the gas nozzle.
[0038] It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative systems embodying the principles of the present subject matter.

DETAILED DESCRIPTION
[0039] The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to clearly communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure as defined by the appended claims.
[0040] It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
[0041] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a",” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
[0042] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0043] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0044] The present invention relates to the developments of various gas nozzle designs for variety of gaseous fuel firing applications. Figures 1 to 6 show the detailed arrangement of various gas nozzle designs for fuel firing applications.
[0045] Referring to Fig. 1, the variant F of the gas nozzle head seen from top. Here the nozzle head (1) is having holes (2) at regular intervals around the diameter of nozzle head. On the sides of nozzle, a flat face (3) is shown for tightening or loosening the gas nozzle head into any gas pipe.
[0046] Referring to Fig. 2, the A-A view of the gas nozzle which is cross-sectional view of gas nozzle variant F, in which the gaseous fuel passes through the space 5 and emit through the nozzle ports 4 at an angle ‘?’. The nozzle head 1 is tapered 6 to provide angled surface. The head receiving end (4) is threaded for easier removal or replacement with supply pipe.
[0047] Referring to Fig. 3, illustrates a gas nozzle variant G, in which the nozzle head 7 has two rows of gas emitting ports 8 and 9 and the flat portion 10 on the receiving side of gas nozzle head for tightening or loosening purpose.
[0048] Referring to Fig. 4, illustrates a B-B view of the gas nozzle which is cross-sectional view of gas nozzle variant G, in which the gaseous fuel passes through the space 12 and emit through the nozzle ports 8 at an angle ‘a’ and gas nozzle ports 9 at an angle ‘ß’. The nozzle head 7 is tapered 13 to provide angled surface for gaseous fuel exit and the nozzle end tip 14 is flat. The head receiving end 11 is threaded for easier removal or replacement with supply pipe.
[0049] While referring to Fig. 5, illustrates a gas nozzle variant H, in which the nozzle head 16 has gas emitting ports 15 and a flat portion 17 on the receiving side of gas nozzle head for tightening or loosening purpose.
[0050] While referring to Fig. 6, illustrates a C-C view of the gas nozzle which is cross-sectional view of gas nozzle variant H, in which the gaseous fuel passes through the space 19 and emit through the nozzle ports 15 at an angle ‘?’. The nozzle head 16 is tapered 21 to provide angled surface for gaseous fuel exit and the nozzle end tip 22 is flat. The head receiving end 18 is threaded for easier removal or replacement with supply pipe
[0051] Details of the Experimentation

The gas nozzles were tested at 10 Mkcal/h gaseous fuel firing boiler with natural gas ad fuel and the results indicates that the flame length is less than 5 m and CO and NOx values are meeting the environmental norms announced in India during 2017.
[0052] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

Claims:We claim:
1. A multi-variant fuel firing gas nozzle, in which a first variant comprising:
a first variant (F) of fuel firing gas nozzle;
a second variant (G) of fuel firing gas nozzle; and
a third variant (H) of fuel firing gas nozzle;
characterized in that:
the first variant (F) of fuel firing gas nozzle comprises:
a gas fuel nozzle head (1);
a plurality of gas emitting ports (2) provided at regular intervals on the gas fuel nozzle head (1);
a passage (5) for gaseous fuel, to allow the entry of gaseous fuel into the gas fuel nozzle at an angle ?;
a fixing arrangement (4) to fix the nozzle with the gas supply pipe,
the second variant (G) of fuel firing gas nozzle comprises:
a gas fuel nozzle head (7);
a plurality of gas emitting ports (8, 9) provided at regular intervals on the gas fuel nozzle head (1);
a passage (12) for gaseous fuel, to allow the entry of gaseous fuel into the gas fuel nozzle at an angle ‘a’ and ‘ß’;
a fixing arrangement (11) to fix the nozzle with the gas supply pipe, and
the third variant (H) of fuel firing gas nozzle comprises:
a gas fuel nozzle head (16);
a plurality of gas emitting ports (15) provided at regular intervals on the gas fuel nozzle head (1);
a passage (19) for gaseous fuel, to allow the entry of gaseous fuel into the gas fuel nozzle at an angle ‘?’; and
a fixing arrangement (18) to fix the nozzle with the gas supply pipe.
2. The multi-variant fuel firing gas nozzle as claimed in claim 1, wherein the number of gas emitting ports (2) vary from 4 to 12 in the first variant (F) of the fuel firing gas nozzle.
3. The multi-variant fuel firing gas nozzle as claimed in claim 1, wherein the angle ‘?’ vary from 10O to 60O.
4. The multi-variant fuel firing gas nozzle as claimed in claim 1, wherein the number of gas emitting ports (8, 9) vary from 8 to 24 in the second variant (G) of the fuel firing gas nozzle.
5. The multi-variant fuel firing gas nozzle as claimed in claim 1, wherein the angle ‘a’ vary from 10O to 60O.
6. The multi-variant fuel firing gas nozzle as claimed in claim 1, wherein the angle ‘ß’ vary from 10O to 70O.
7. The multi-variant fuel firing gas nozzle as claimed in claim 1, wherein the angle ‘a’ and ‘ß’ need not be the same and the maximum deviation is 20O.
8. The multi-variant fuel firing gas nozzle as claimed in claim 1, wherein the number of gas emitting ports (15) vary from 8 to 30 in the third variant (H) of the fuel firing gas nozzle.
9. The multi-variant fuel firing gas nozzle as claimed in claim 1, wherein the angle ‘F’ vary from 10O to 80O.
10. The multi-variant fuel firing gas nozzle as claimed in claim 1, wherein the diameter of gas emitting port is between 4 mm to 30 mm.