CN116293684A

CN116293684A - Burner module

Info

Publication number: CN116293684A
Application number: CN202211648338.9A
Authority: CN
Inventors: 马西莫·吉廖利; 桑德罗·卢利
Original assignee: Beckett Thermal Solutions LLC
Current assignee: Beckett Thermal Solutions LLC
Priority date: 2021-12-21
Filing date: 2022-12-21
Publication date: 2023-06-23
Also published as: EP4202298A1; IT202100032039A1; EP4202298B1; EP4202298C0

Abstract

A burner module for a gas mixture, comprising: a plurality of nozzles (20), each nozzle having an outlet (21) of diameter (D); a discharge plane (E) on which the outlet (21) of the nozzle (12) is located; -a connection plane (S) at which the attachment of the burner module to the support structure is located; wherein the nozzles (20) are spaced apart from each other by a constant pitch (P); wherein the connection plane (S) and the discharge plane (E) are parallel to each other and spaced apart by a main height (H). The dimensional parameter (R) given by the product between said main height (H), said pitch (P) and the diameter (D) of the outlet (21) of the nozzle (20), measured in millimeters, is comprised between 71 and 84, namely: r=h P D;71 < R < 84.

Description

Burner module

Technical Field

The present invention relates to a burner module which can be used, for example, in a wall boiler.

Background

The burner module typically includes a manifold for the combustible gas. Such manifolds are generally tubular and comprise substantially cylindrical conduits closed at the ends.

The manifold is provided with a plurality of nozzles, i.e. calibrated openings which put the interior of the manifold in communication with the external environment. The nozzles are placed side by side with each other and aligned along a generatrix of the outer surface of the manifold.

A plurality of burner modules are juxtaposed to one another to define a modular burner.

The nozzles are used to allow the combustible gas to be discharged outside the manifold so that combustion can occur. In particular, the combustible gas flowing out of the collector through the nozzle is fed to the burner and the flame is generated above the burner module. Additional combustion air (called secondary air) is supplied to the flame from the surroundings.

The combustion products include carbon monoxide (CO) and nitrogen oxides (NOx) as well as other compounds. As is known, both compounds should be reduced as much as possible.

The amount of CO and NOx produced by combustion depends on various parameters, including the ratio of fuel to primary air, and the amount of secondary air relative to the flow rate at which the nozzle is discharging. For example, a limited primary air supply results in a significant reduction in the Langda (Lambda) of the combustible air mixture. This means that in the part closest to the flame diffuser, the flame temperature is above the critical value for nitrogen oxide (NOx) formation. This phenomenon is particularly prominent in low power conditions of the boiler and is of course undesirable for obvious reasons related to the suppression of harmful emissions.

Thus, the design of the burner module is very important for achieving optimal combustion conditions with low emissions of harmful compounds. In particular, the diameter of the nozzles, the number of nozzles and the spacing between them, the collector section must be chosen with great care in order to suppress the emission of harmful compounds.

Currently, the design of burner modules is essentially done empirically, models are developed and their performance during operation is tested. In case the performance is not satisfactory, one or more geometrical parameters of the model have to be modified for subsequent testing until a satisfactory configuration is obtained.

Thus, current designs are relatively slow and laborious. Furthermore, in case one or more parameters of the burner module need to be modified, it is not allowed to easily adapt the other parameters to the optimal operation.

Disclosure of Invention

It is an object of the present invention to provide a burner module which allows to obtain optimal operating conditions, has low emissions of harmful compounds and can be quickly designed according to different construction and/or installation requirements.

Accordingly, the present invention provides a burner module for a gas mixture comprising: a manifold provided with a tubular body defining an inner cavity; a plurality of nozzles disposed through the tubular body, each of the nozzles having an outlet; a discharge plane, the outlet of the nozzle being located on the discharge plane; a pair of brackets arranged to enable attachment of the manifold to a support structure, and having attachment portions for attachment to the support structure; a connection plane on which the attachment portion is located and on which the attachment with the support structure is located. Wherein the outlets of the nozzles have equal diameters D. Wherein the nozzles are spaced apart from each other by a constant pitch P. Wherein the connection plane and the discharge plane are parallel to each other and spaced apart by a main height H. Wherein a dimensional parameter R, given by the product between said main height H measured in millimeters, said pitch P and said diameter D of said outlet of said nozzle, is comprised between 71 and 84, namely: r=h P D;71 < R < 84.

Drawings

The features and advantages of the present invention will become more fully apparent from the following detailed description of embodiments of the invention, given by way of non-limiting example in the accompanying drawings, in which:

FIG. 1 shows a schematic view of a burner module according to the invention in a vertical elevation;

FIG. 2 illustrates a top view of the combustor module of FIG. 1;

fig. 3 shows a cross-section on the plane A-A of fig. 2.

Detailed Description

The burner module according to the invention comprises a manifold 10 provided with a tubular body 11 defining an inner cavity 12. The manifold 10 is provided with an inlet 13 through which a combustible gas can be introduced into the tubular body 11.

The plurality of nozzles 20 are arranged so as to penetrate the tubular body 11. In a manner known in the art, each nozzle comprises a threaded body 22 through which a calibrated through hole is obtained, at one end of which an outlet 21 of the nozzle 20 is arranged. The threaded body 22 is screwed into a corresponding through hole obtained through the wall of the tubular body 11. The outlets 21 have the same diameter D.

The outlets 21 of the nozzles 20 lie on a common discharge plane E. In particular, the nozzle 20 is aligned along a direction parallel to the longitudinal axis X of the tubular body 11. Further, the nozzles 20 are spaced apart from each other at a constant pitch P. This pitch P is basically the distance separating the outlets 21 from each other. In practice, each outlet 21 is separated from two adjacent outlets by a distance P.

The burner module further comprises a pair of brackets 30 arranged to enable attachment of the manifold 10 to a support structure, not shown. Such a support structure is for example a suitable attachment element provided in a wall boiler or in a water heater, or typically an attachment element provided in a device in which the burner module is mounted. Preferably, but not necessarily, the support 30 is positioned at the end of the tubular body 11. In the depicted embodiment, the stent 30 has a joining portion 32 where the stent is connected to the tubular body 11, closing the ends of the tubular body.

The bracket 30 also has an attachment portion 31 arranged to enable connection to the support structure of the device in which the burner module is envisaged to be mounted. The attachment portions lie on the same connection plane S parallel to the emission plane (emission plane) E. The attachment to the support structure is located on the connection plane.

The connection plane S and the discharge plane E are separated by a main height H. In other words, the main height H is a distance separating the connection plane S and the discharge plane E.

After extensive research, the applicant has determined a dimensional parameter R which is very relevant to the correct design of the burner module, i.e. to the limitation of the compounds emitted by the combustion of the mixture.

The dimensional parameter R is given by the product between said main height H, said pitch P and the diameter D of the outlet 21 of the nozzle 20. Thus, the dimensional parameter R is the volume.

If the product thereof defines a dimensionThe dimensions H, P, D of the parameter R are measured in millimeters, the applicant has found that they are comprised in 71mm ³ And 84mm ³ The R values in between allow NOx emissions to be well limited below 90mg/kWh and CO emissions to be well limited below 1000 ppm.

In practice, if:

R＝H*P*D；

71＜R＜84mm ³ ，

NOx emissions remained well below 90mg/kWh, and CO emissions remained well below 1000 ppm.

Due to the determination of the dimensional parameter R, the design of the burner module can be significantly simplified.

For example, given the diameter of the outlet 21, which is generally a function of the type of fuel used and depends on the configuration of the nozzle 20, and the main height H is known, which is dependent on the position and the required installation of the burner module, it is instantaneous to obtain the optimal pitch P at which the nozzle 20 is placed. For example, in the case of natural gas, the diameter of the outlet 21 is comprised between about 0.9mm and 1.5mm as a function of the operating pressure.

Conversely, if the configuration of the nozzle 20 requires a predetermined mounting pitch P, the dimensional parameter R allows to obtain an optimal main height H.

Preferably, said dimension parameter R is comprised between 75 and 80, namely:

75＜R＜80。

within this range, comprised between 75 and 80, NOx is kept below 85mg/kWh, while CO is kept below 800 ppm.

A plurality of burner modules according to the invention may be arranged to form a modular burner. The burner modules are arranged alongside one another with the same discharge plane E and the same connection plane S. In a preferred embodiment, the modular burner comprises twenty-one burner modules.

Examples of further particularly effective configurations of modular burners comprising a plurality of burner modules according to the invention provide nineteen or thirty-one burner module. In all cases, the combustion conditions are optimal and emissions of harmful compounds are reduced.

The burner module according to the invention has important advantages over the prior art.

First, the burner module allows to obtain optimal combustion conditions, including the amount of emitted harmful compounds, in particular NOx and CO.

In addition, the definition of the dimensional parameter R allows to greatly simplify the design of the burner module, ensuring a certainty of the amount of harmful compounds emitted, without the need to make prototypes to test its operation.

Claims

1. A burner module for a gas mixture, comprising:

a manifold (10) provided with a tubular body (11) defining an inner cavity (12);

-a plurality of nozzles (20) arranged through said tubular body (11), each of said nozzles having an outlet (21);

-a discharge plane (E) on which the outlet (21) of the nozzle (12) is located;

a pair of brackets (30) arranged to enable attachment of the manifold (10) to a support structure, and having attachment portions (31) for attachment to the support structure;

-a connection plane (S), on which the attachment portion (31) is located, and on which the attachment with the support structure is located;

wherein the outlets (21) of the nozzles have equal diameters (D);

wherein the nozzles (20) are spaced apart from each other by a constant pitch (P);

wherein the connection plane (S) and the discharge plane (E) are parallel to each other and spaced apart by a main height (H);

the method is characterized in that:

the dimensional parameter (R) given by the product between the main height (H), the pitch (P) and the diameter (D) of the outlet (21) of the nozzle (20), measured in millimeters, is comprised between 71 and 84, namely:

R＝H*P*D；

71＜R＜84。

2. burner module according to claim 1, wherein said dimensional parameter (R) is comprised between 75 and 80, namely:

75＜R＜80。

3. a modular burner comprising a plurality of burner modules according to claim 1 or 2, arranged side by side with the same emission plane (E) and the same connection plane (S).

4. A modular burner according to claim 3, comprising twenty-one burner modules according to claim 1 or 2.

5. A modular burner according to claim 3, comprising nineteen burner modules according to claim 1 or 2.

6. A modular burner according to claim 3, comprising thirty-one burner modules according to claim 1 or 2.