JP2018096643A - Regenerative burner and heating furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a regenerative burner capable of simplifying loading work for several heat reservoirs constituting a heat storage part.SOLUTION: There are provided a fluid flow passing part A where a cylindrical heat storage part U is arranged at a cylindrical space between an outer cylinder part 1 and an inner cylinder part 2 concentrically arranged; a fuel gas discharging part G installed inside the inner cylinder part 2; and a combustion state changing-over part changing over between a combustion state in which combustion air F is supplied to a burner extremity end side through the fluid flow passing part A and a heat storage state for flowing combustion discharged gas E from the burner extremity end side to the burner base end side through the fluid flow passing part A. The heat storage part U is constituted in a form where several cylindrical heat storage reservoirs 3 of honeycomb structure are arranged while their setting clearances are being spaced apart in a fluid flowing direction at the fluid flow passing part A and the heat storage reservoirs 3 are integrally molded with spacer portions 3a for use in spacing apart a setting clearance L between the adjoining heat storage reservoirs 3.SELECTED DRAWING: Figure 1

Description

The present invention is arranged in a fluid flow part in which a cylindrical heat storage part is arranged in a cylindrical space between an outer cylinder part and an inner cylinder part arranged concentrically, and inside the inner cylinder part. A fuel gas discharge section, a combustion state in which combustion air is supplied to the burner tip side through the fluid flow portion, and a heat storage state in which combustion exhaust gas is passed from the burner tip side to the burner base end side through the fluid flow portion. A combustion state switching unit for switching,
The present invention relates to a heat storage burner in which the heat storage section is configured in such a manner that a plurality of tubular heat storage bodies having a honeycomb structure are arranged at a set interval in the fluid flow direction of the fluid flow section.

Such a regenerative burner is installed in a heating furnace that heats various objects to be heated, such as, for example, installed in a heating furnace that heat-treats steel materials for quenching. The regenerative burner is provided in an alternating combustion mode in which alternating combustion is performed.
That is, a plurality of heat storage type burners are provided in an alternating combustion mode in which the remaining heat storage type burners are in a combustion state when some of the heat storage type burners are in a heat storage state.

  Further, such a heat storage type burner is arranged such that a plurality of cylindrical heat storage bodies having a honeycomb structure constituting the heat storage section are arranged in a form in which a set interval is separated in the fluid flow direction of the fluid flow section, so that combustion air and Even if the flue gas flows in a so-called drift state where a part of the range of the heat storage body flows more than the other part of the heat storage body on the upper side in the flow direction, By reaching the heat storage body adjacent in the direction, the drift state can be eliminated, and the combustion air and the combustion exhaust gas can flow as uniformly as possible with respect to the entire heat storage body adjacent in the flow direction (for example, (See Patent Document 1).

Japanese Patent No. 3754507

  In order to arrange a plurality of heat storage bodies constituting the heat storage section in a form in which the set interval is separated in the fluid flow direction of the fluid flow section, for example, positioning for receiving and supporting the end surface along the fluid flow direction of the heat storage body It can be considered that the positioning support is attached to the outer peripheral surface of the inner cylinder part or the inner peripheral surface of the outer cylinder part, such as attaching the support for welding to the outer peripheral surface of the inner cylinder part.

  In other words, when one heat storage body is loaded, a positioning support body is mounted on the end surface facing the adjacent heat storage body in the loaded heat storage body, and then loaded in the heat storage body adjacent to the loaded heat storage body In the procedure for mounting the mounting positioning support for the end face facing the heat storage body at a position for receiving the adjacent heat storage body at a set interval with respect to the loaded heat storage body, the heat storage body It is conceivable that a positioning support is mounted every time the is loaded.

  However, the work of mounting the positioning support every time the heat storage body is loaded is a cumbersome and time-consuming work, and improvement is desired.

  This invention is made in view of the said situation, Comprising: It exists in the point which provides the thermal storage type burner which can aim at simplification of the loading operation | work of the several thermal storage body which comprises a thermal storage part.

The regenerative burner of the present invention includes a fluid flow passage portion in which a tubular heat storage portion is disposed in a tubular space between an outer tube portion and an inner tube portion that are concentrically disposed, and an interior of the inner tube portion. A combustion state in which combustion air is supplied to the burner tip side through the fluid flow part and the combustion exhaust gas is caused to flow from the burner tip side to the burner base side through the fluid flow part. A combustion state switching part for switching to a heat storage state is provided,
The heat storage part is configured in a form in which a plurality of cylindrical heat storage bodies having a honeycomb structure are arranged in a form spaced apart from each other in a fluid flow direction of the fluid flow part,
The characteristic configuration is that a spacer portion for separating the set interval between the heat storage body and the adjacent heat storage body is integrally formed.

  That is, since the spacer part for positioning the adjacent heat storage body at a set interval is integrally formed with the heat storage body, the plurality of heat storage bodies are placed in the cylindrical space between the outer cylinder part and the inner cylinder part. If loaded, due to the presence of the spacer portion, the plurality of heat storage bodies are loaded in a form with a set interval between adjacent heat storage bodies.

  Therefore, it is not necessary to perform a special operation in order to load adjacent heat storage bodies in a form with a set interval therebetween, and the work of loading a plurality of heat storage bodies can be simplified.

  In short, according to the characteristic configuration of the heat storage burner of the present invention, it is possible to simplify the work of loading a plurality of heat storage bodies constituting the heat storage section.

  The further characteristic structure of the heat storage type burner of this invention exists in the point in which the said spacer part is formed in the edge part by the side of the internal diameter in the said heat storage body.

  That is, since the spacer portion is formed at the inner diameter side end portion of the heat storage body, the opposing end surfaces of the adjacent heat storage bodies are largely opened, so that it is easy to avoid the drift appropriately.

  In other words, it is adjacent to the end portion on the inner diameter side (smaller diameter side) of the heat storage body than to form the spacer portion on the outer diameter side (large diameter side) end portion of the heat storage body. Since the opposing end surfaces of the heat storage body are largely opened, it is easy to avoid the drift appropriately.

  In short, according to the further characteristic configuration of the regenerative burner of the present invention, it is easy to avoid the drift appropriately.

  The further characteristic structure of the heat storage type burner of this invention exists in the point by which the said several heat storage body is formed in the same form.

  That is, since the plurality of heat storage bodies are formed in the same form, compared to the case where the plurality of heat storage bodies are formed in different forms, the heat storage body can be molded in one type, etc. Simplification of production can be achieved.

  In short, according to the further characteristic configuration of the heat storage burner of the present invention, it is possible to simplify the manufacture of the heat storage body.

  A characteristic configuration of the heating furnace according to the present invention is that a plurality of the above-described regenerative burners are provided in an alternating combustion mode in which a part of the regenerative burners is set to the heat storage state, and the remaining heat storage burners are set to the combustion state. There is in point.

  That is, since the plurality of regenerative burners that are switched between the heat storage state and the combustion state perform alternating combustion, while preheating the combustion air using the heat held by the combustion exhaust gas discharged outside the furnace, Since the regenerative burner can be burned, the object to be heated can be heated while improving energy saving.

  In addition, each of the plurality of heat storage burners can appropriately heat the combustion air with the stored heat while favorably storing the heat of the combustion exhaust gas in each of the plurality of heat storage bodies constituting the heat storage unit. Therefore, the energy saving performance can be appropriately improved while appropriately preheating the combustion air.

  In short, according to the characteristic configuration of the heating furnace of the present invention, the energy saving performance can be appropriately improved.

Vertical side view of a regenerative burner Perspective view of heat storage Outline cross-sectional plan view of the heating furnace Explanatory drawing showing alternating combustion mode

Embodiment
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Overall structure of heating furnace)
As shown in FIG. 3, the illustrated heating furnace includes a plurality of regenerative burners B that form in the furnace space N a flame M that heats the object to be heated D conveyed through the furnace space N of the furnace body H. The heated object D, which is provided along the longitudinal direction of the conveying path R of the heated object D and is inserted into the furnace space N along the conveying path R, is converted into a plurality of regenerative burners B. It is configured to heat.
Incidentally, the temperature of the furnace space N of the furnace body H is, for example, about 800 ° C. to 1000 ° C.

  In the present embodiment, four heat storage burners B are provided on each of the lateral side wall portions of the furnace body H in a state of being arranged two by two along the longitudinal direction of the transport path R, and the four heat storage burners B are arranged. The expression burner B is configured to alternately burn as described later.

(Configuration of heat storage burner)
As shown in FIG. 1, the heat storage burner B has a fluid flow in which a cylindrical heat storage unit U is disposed in a cylindrical space between the outer tube portion 1 and the inner tube portion 2 that are concentrically disposed. Part A, fuel gas discharge part G arranged inside the inner cylinder part 2, combustion state in which combustion air F is supplied to the burner tip side through the fluid flow part A, and combustion exhaust gas E through the fluid flow part A Is provided with a combustion state switching section K (see FIG. 3) for switching to a heat storage state in which the gas flows from the burner tip side to the burner base end side.

In the present embodiment, a supply / exhaust chamber 4 communicating with the heat storage unit 3 is formed at the rear end portion of the fluid flow section A, and the supply passage 5 is connected to the supply joint 4A of the supply / exhaust chamber 4. Is connected, and the exhaust passage 6 is connected to the exhaust joint 4 </ b> B of the supply / exhaust chamber 4.
An air supply fan P (see FIG. 3) for supplying air in the atmosphere as combustion air is connected to the air supply path 5, and an exhaust fan Q (for sucking and discharging combustion exhaust gas outside the furnace is connected to the exhaust path 6. Are connected).

The fuel discharge portion G includes a double tubular tube portion 7 including a concentric large diameter tube and a small diameter tube, and the burner axial center direction is between the large diameter tube and the small diameter tube of the tube portion 7. A fuel passage is formed, and an annular fuel ejection portion 7A is formed at the tip of the fuel passage.
A fuel supply joint 9 to which fuel gas is supplied is provided at a location on the rear end side of the above-described supply / exhaust chamber 4, and the fuel gas supplied from the fuel supply joint 9 passes through the fuel passage of the cylinder portion 7 to form a fuel. It is configured to be introduced into the ejection portion 7A.

Although not shown, a pilot combustion nozzle is provided inside the annular fuel injection portion 7A, and as shown in FIG. 1, fuel gas for pilot combustion is supplied to the rear end portion of the fuel supply joint 9. A pilot fuel supply joint 10 and a pilot air supply joint 11 for supplying combustion air for pilot combustion are provided in communication with the small diameter cylinder of the cylinder portion 7 and supplied from the pilot fuel supply joint 10. The fuel gas and the combustion air supplied from the pilot air supply joint 11 are configured to be supplied to the pilot combustion nozzle U through the internal space of the small-diameter cylinder in the double tubular cylinder 7.
Although not shown, an ignition spark rod for igniting the mixed gas ejected from the pilot combustion nozzle is disposed in the internal space of the small-diameter cylinder in the double tubular cylinder 7.

  In the present embodiment, the tip portion 1A located on the burner tip side with respect to the fluid flow portion A in the outer cylinder portion 1 is formed in a form having a smaller diameter toward the tip side, and the regenerative burner B is switched to the combustion state. In this state, the combustion air F supplied through the fluid flow part A is made to flow at high speed to the burner tip side, whereby the fuel gas and the combustion air F injected from the fuel injection part 7A of the fuel discharge part G It is configured so as to reduce NOx by slowing the mixing with NO.

(Details of heat storage unit)
As shown in FIG. 1, the heat storage unit U is configured in a form in which a plurality of tubular heat storage bodies 3 having a honeycomb structure are arranged in a form in which a set interval L is separated in the fluid flow direction of the fluid flow part A. In addition, a spacer portion 3a for separating a set interval L between the heat storage body 3 and the adjacent heat storage body is integrally formed.
Incidentally, the honeycomb structure of the heat accumulator 3 means a structure having a large number of flow paths along the fluid flow direction of the fluid flow section A.

In the present embodiment, the heat accumulator 3 has an outer diameter of 155 mm, an inner diameter of 62 mm, and a length along the fluid flow direction of the fluid flow section A of 70 mm.
In the present embodiment, the spacer portion 3 a is formed at the end portion on the small diameter side of the heat storage body 3. Specifically, the spacer portion 3a has an outer diameter of 82 mm, an inner diameter of 62 mm, and a length along the fluid flow direction of the fluid flow portion A that is 10 mm.

In the present embodiment, three heat storage bodies 3 are arranged in parallel along the fluid flow direction of the fluid flow section A, and the three heat storage bodies 3 are formed in the same form.
That is, the three heat accumulators 3 have the same outer diameter, inner diameter, and length, and have the same specifications in which a number of flow paths along the fluid flow direction are similarly formed.
Incidentally, the flange part of the inner cylinder part 2 in which the spacer part 3a of the heat storage element 3 on the burner rear end side among the three heat storage elements 3 is flange-connected to the cylindrical support part 12 provided inside the supply / exhaust chamber 4. The outer periphery of the heat accumulator 3 on the burner distal end side of the three heat accumulators 3 is applied to the base end portion of the distal end portion 1A in the outer cylinder portion 1. Thus, the position of the fluid flow part A in the fluid flow direction is positioned.

(Details of alternating combustion)
As shown in FIG. 3, the air supply path 5 is configured to connect the air supply fan P and the plurality of heat storage burners B in parallel, and each of the four heat storage burners B in the air supply path 5 is connected. A corresponding portion is provided with an air supply valve 15 for intermittently supplying the combustion air.
The exhaust passage 6 is configured to connect the exhaust fan Q and the plurality of heat storage burners B in parallel, and the exhaust passage 6 is provided in a portion corresponding to each of the four heat storage burners B in the exhaust passage 6. An exhaust valve 16 that opens and closes is provided.

As shown in FIG. 1, the fuel supply joint 9 of the regenerative burner B is connected to a fuel gas supply passage 17 for supplying a fuel gas such as city gas mainly composed of methane, as shown in FIG. The fuel gas supply path 17 is provided with a fuel valve 18 for intermittently supplying the fuel gas to each regenerative burner B.
Incidentally, the combustion state switching unit K is configured to switch each heat storage burner B between a combustion state and a heat storage state with the air supply valve 15, the exhaust valve 16 and the fuel valve 18 as main parts.

  That is, by closing the supply valve 15 and the fuel valve 18 and opening the exhaust valve 16, the heat storage burner B enters a heat storage state, and by opening the supply valve 15 and the fuel valve 18 and closing the exhaust valve 16, The expression burner B is configured to be in a combustion state.

  That is, the supply fan P supplies the combustion air F to the regenerative burner B in the combustion state, sucks the combustion exhaust gas E in the furnace space N, and discharges it to the outside of the furnace. When the fuel gas is supplied to the heat storage burner B in the combustion state, the plurality of heat storage burners B are switched between the heat storage state and the combustion state. (See FIG. 4).

  In addition, a combustion control unit (not shown) that controls the combustion of the regenerative burner B controls opening / closing of the air supply valve 15, the fuel valve 18, and the exhaust valve 16, and a part of the plurality of regenerative burners B When the heat storage type burner B is in a heat storage state, the plurality of heat storage type burners B are combusted in an alternating combustion mode in which the remaining heat storage type burner B is switched to a combustion state.

In the present embodiment, as shown in FIGS. 3 and 4, two regenerative burners B arranged along the longitudinal direction of the transport path R are alternately burned on both lateral side walls of the furnace body H. It is configured.
Specifically, among the four regenerative burners B arranged in a state of being positioned at the corners of the quadrangle in plan view, a pair of regenerative burners B positioned in a diagonal line is used as a pair, and two regenerative burners B Is configured to alternately burn.

  Incidentally, in FIG. 3, among the air supply valve 15, the exhaust valve 16, and the fuel valve 18, those that are in the closed state are shown in black, and among the air supply valve 15, the exhaust valve 16, and the fuel valve 18, The open state is shown in white.

  Although not shown, the air supply passage 5 is equipped with an air supply damper that changes and sets the supply amount of combustion air, and the exhaust passage 6 has an exhaust damper that changes and sets the exhaust amount of combustion exhaust gas. The fuel gas supply path 17 is equipped with a fuel adjustment valve that changes and sets the supply amount of the fuel gas, and the combustion amount of the plurality of regenerative burners B is supplied to the supply damper, the exhaust damper, and It is adjusted by operating the fuel adjustment valve.

[Another embodiment]
Next, another embodiment is listed.
(1) In the said embodiment, although the case where the four heat storage type burners B were equipped with respect to the in-furnace space N with which the heat processing material D was conveyed along the conveyance path | route R was illustrated, the heat storage type burner is shown. The number of B and the installation form can be variously changed in a specific form of the heating furnace.

(2) In the above embodiment, the regenerative burner B has exemplified the form in which the flame M is formed in the in-furnace space N of the heating furnace, but the regenerative burner B of the present invention is in the internal space of the radiant tube. The flame M may be formed in a so-called radiant tube type.

(3) In the said embodiment, although the heat storage part U illustrated the case where the three heat storage bodies 3 are arrange | positioned in the cylindrical space between the outer cylinder part 1 and the inner cylinder part 2, the heat storage to arrange | position The number of installed bodies 3 can be variously changed.

(4) In the above embodiment, the case where a plurality of heat storage bodies 3 are formed to the same specification is exemplified, but the length of the fluid flow section A of each heat storage body 3 in the fluid flow direction is different. The specifications of the plurality of heat storage bodies 3 may be different.

(5) In the above embodiment, when three heat storage bodies 3 are arranged, the setting interval L between the adjacent heat storage bodies 3 is exemplified as the same interval, but three or more heat storage bodies are illustrated. In the case of arranging 3, the set interval L between the adjacent heat storage bodies 3 can be variously set such that all the set intervals L between the adjacent heat storage bodies 3 are different or only a part thereof is different. .

  The configuration disclosed in the above embodiment (including another embodiment, the same shall apply hereinafter) can be applied in combination with the configuration disclosed in the other embodiment, as long as no contradiction occurs. The embodiment disclosed in this specification is an exemplification, and the embodiment of the present invention is not limited to this. The embodiment can be appropriately modified without departing from the object of the present invention.

DESCRIPTION OF SYMBOLS 1 Outer cylinder part 2 Inner cylinder part 3 Thermal storage body 3a Spacer part K Combustion state switching part

Claims (4)

A fluid flow part in which a cylindrical heat storage part is arranged in a cylindrical space between the outer cylinder part and the inner cylinder part arranged concentrically, and a fuel gas discharge part arranged in the inner cylinder part Switching between a combustion state in which combustion air is supplied to the burner tip side through the fluid flow part and a heat storage state in which combustion exhaust gas is passed from the burner tip side to the burner base side through the fluid flow part Are provided,
The heat storage section is a heat storage burner configured in a form in which a plurality of cylindrical heat storage bodies having a honeycomb structure are arranged in a form in which a set interval is separated in a fluid flow direction of the fluid flow section,
A heat storage burner in which a spacer portion for separating the set interval between the heat storage body and the adjacent heat storage body is integrally formed.   The regenerative burner according to claim 1, wherein the spacer portion is formed at an inner diameter side end portion of the heat storage body.   The heat storage burner according to claim 1 or 2, wherein the plurality of heat storage bodies are formed in the same form.   A plurality of the regenerative burners according to any one of claims 1 to 3 are provided in an alternating combustion mode in which a part of the regenerative burners is set to the heat storage state, and the remaining heat storage burners are set to the combustion state. Heating furnace.

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