JPS5826488B2 - Heat storage tile structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention describes the use of a zirconium oxide-encoded, centrally orifice-coated metallic flame retardant for significantly and very rapidly increasing the flame temperature by recirculating hot flame gases. The present invention relates to a regenerative tile structure for a fluid fuel burner having a flange-shaped member.

Here, °°Thermal Tile Structure'' (Regene
The term "rative tile 5structure" shall mean a tile structure having structures or surfaces that possess such high temperatures as to regenerate combustion of the fuel or maintain self-sustaining combustion of the fuel.

In the combustion of all fluid fuels, the stable flammability of the fuel and its combustion rate are important.

The rapid and stable combustion of virtually any type of fuel has been a continually pursued goal since fuel burners were first invented.

It is known in the field of fluid fuel combustion that the highest possible initial flame temperature is key to fuel combustion rate and stability of fuel combustion.

However, when burning waste gas that has a certain amount of heat, it is difficult to maintain the initial flame temperature at the maximum value or maintain the stability of fuel combustion.

In the past, thermal storage tile structures with burner devices have been effective as a means of obtaining the desired self-sustaining and rapid combustion of fuel.

The basic operating principle underlying these constructions is to provide a sufficiently high flame temperature for effective fuel combustion.

Such flame temperatures are maintained by burning fuel in a refractory-lined area for heat retention and recirculating heated flame gases through the area.

One such device is U.S. Pat. No. 3,711,243
Disclosed in the issue.

In that device, atomized fuel is sprayed into a cylindrical combustion zone surrounded by annularly shaped ceramic tiles.

A second ceramic member having a downstream facing surface disposed perpendicular to the axis of the first ceramic tile is disposed near the upstream end of the first tile and is centrally located for injecting fuel into the combustion zone and inlet of air. It has an opening.

The downstream surface of this second ceramic member serves to guide the recirculation of heated flame gases into the inlet air stream and to increase the flame temperature.

Under certain combustion conditions, it is necessary to direct airflow directly along the downstream face of the first annular tile to prevent carbon buildup.

To achieve this result, it was necessary for the second ceramic member to have an outer diameter slightly smaller than the inner diameter of the first tile, thus forming an annular air passage.

While such known devices are effective, it is clear that a simplified construction could reduce construction costs and improve frame temperature rise, thereby increasing the value of the invention to the industry. .

Furthermore, directing the heated gas back into the air/fuel mixture at right angles dilutes the supplied inlet air, which slows the combustion reaction and also reduces the desired effect provided by high flame temperatures. ing.

SUMMARY OF THE INVENTION Therefore, the present invention provides a simplified heat storage tile structure for use in the combustion of fluid fuels, which is less expensive to construct than known devices and which allows significantly higher flame temperatures to be obtained. provide.

This novel invention comprises a cylindrical metal shell, an annular heat-resistant sleeve, and a metal flange-shaped member providing a central orifice for introducing fuel and air into the heat-resistant sleeve. have.

This annular refractory sleeve is placed downstream of the metal shell to form a combustion zone.

The downstream end surface of the sleeve preferably extends beyond the end of the shell and abuts the end in an arched manner to protect the end of the shell from high temperatures.

A metal flange-shaped member coated with zirconium oxide is disposed within the shell against the upstream surface of the annular refractory sleeve and has a central orifice.

This flange edge forming the orifice is arched and projects downstream to provide maximum air supply therethrough.

The hot flame gas being recirculated by this arcuate projection is not directly fed into the air stream as is known, but is instead fed downstream.

For fuels that tend to accumulate carbon on the inner upstream surface of the refractory sleeve, holes are provided in this flange-shaped member near the inner surface of the refractory material as a passageway for sucked air.

A specific example will be described below.

Referring to the drawings, particularly FIG. 1, the numeral 10 generally indicates a regenerative tile structure suitable for burning a variety of fluid fuels.

This tile structure 10 is attached in some suitable manner (not shown) to an end plate 12 which is further attached to the wall of a furnace (not shown) in a known manner, such as by a plurality of spacer bolts 13. 14 and positioned to substantially align with an opening 16 in the furnace wall.

The tile structure 10 has a substantially cylindrical metal shell 18 having a plurality of peripheral openings 20 in its upstream portion for admitting air from the outside to the inside.

An annular heat resistant sleeve 22, preferably shorter than the length of the shell 18, is mounted downstream of the shell 18 and secured to the inner periphery of the shell 18 in any suitable manner.

The downstream end of the heat resistant sleeve 22 projects from the downstream end of the shell 18 and is preferably arcuate or curved in cross-sectional shape, with a periphery extending sufficiently outwardly to cover the end of the shell 18. The lip portion forms an annular shoulder.

This lip extension 23 protects the ends of the shell from high temperatures.

A flange-like metal member 24 is fixed to the shell 18, preferably against the upstream end of the heat-resistant sleeve 22, and provides a discharge orifice 25 for the centrally located tile structure 10.

A suitable nozzle 26 extends through the end plate 12 into the interior of the shell 18 and has a plurality of jets or apertures 27 in the vicinity of the discharge orifice 25 for discharging fuel lath in the area defined by the heat resistant sleeve. It's gushing.

These jets desirably provide a substantially conical spray pattern of fuel.

Fuel spray from nozzle 26 and air entering the tile structure through the peripheral openings are ejected through orifice 25.

The metal member 24 directly surrounding the orifice is numbered 29.
It arches downstream, as shown, and forms a smooth passage for the air sucked into the area defined by the heat-resistant sleeve.

The flange-shaped member 24 is preferably coated with zirconium oxide to protect the member at high temperatures.

The protrusion depth X of the flange in the downstream direction is not greater than the depth effective to increase the flame temperature.

The desired protrusion depth X is smaller than the thickness of the flange surface,
It is known that it is approximately 10% of the flange surface diameter.

As mentioned above, in the known arrangement hot recirculated flame gas is forced through a central orifice in a direction perpendicular to the central orifice together with the inlet air, which weakens the oxygen supply and thus reduces the initial combustion. It delayed the reaction.

However, in the present invention, the protrusion 29 of the downstream flange member 24 directs the recycle gas substantially downstream, so that the air is free from combustion inhibiting mixing with the relatively inert recycle gas produced by known devices. It can be seen that it delays

The shape of the flange member orifice also creates a low pressure area due to fuel flow.

In the present invention, this fuel flow is more concentrated than in the prior art and is concentrated in a space directly adjacent to the orifice, thus minimizing air-fuel reaction delays.

For some fuels, it is necessary to direct air along the upstream inner surface of the refractory sleeve to prevent carbon buildup.

In the embodiment shown in FIGS. 3 and 4, the flange portion 28
has a plurality of holes 30 spaced around a central orifice 31 and spaced slightly inwardly from the inner periphery of the heat resistant sleeve 22 .

In addition to the air entering the combustion zone via the central orifice 31, air is also drawn in through these holes 30 by suction.

It is clear that the simplified structure of the present invention increases the flame temperature while providing significant economy over conventional devices and increasing the efficiency of the device.

Although this invention has been described with respect to the specific relationships in the accompanying drawings, it will be understood that modifications other than those shown and implied herein are within the spirit and scope of the invention.

[Brief explanation of drawings]

FIG. 1 is a front view of a new heat storage tile structure embodying the present invention and installed in a furnace; FIG. 2 is a view taken along line 2-2 of FIG. 1; FIG. FIG. 4 is a view taken along line 4--4 of FIG. 3. Description of the symbols, 10; Tile structure, 16; Opening, 18; shell, 20: peripheral mouth, 22; heat-resistant sleeve, 23; lip, 24; member, 25; orifice, 26: nozzle,
27; opening, 28; flange member, 29; protrusion, 30
; hole.

Claims (1)

Claims: 1. A regenerative tile structure for a fluid fuel burner comprising: a substantially cylindrical shell; an axial tile structure secured to the inner periphery of the cylindrical shell and axially disposed on a downstream portion of the shell; an annular heat-resistant sleeve disposed in: a flange-shaped member abutting the upstream end of the iron annular heat-resistant sleeve and fixed around the inner periphery of the shell, the member having an orifice coaxially disposed therein; an edge of said flange-shaped member defines said orifice projecting in a downstream direction, and a plurality of peripherally spaced circumferences about said orifice spaced slightly inwardly from said inner circumference of said annular heat resistant sleeve. 1. A regenerative tile construction for a fluid fuel burner, comprising: a flange-shaped member having apertures therein; and means for introducing combustion air into the shell upstream of the flange-shaped member. 2. The thermal storage tile structure of claim 1, wherein the annular heat resistant sleeve has an outwardly extending peripheral shoulder near the downstream end of the cylindrical shell. 3. The heat storage tile structure according to claim 2, wherein the outer end of the heat-resistant sleeve has an arched cross-sectional shape. 4. The heat storage tile structure according to claim 2, wherein the shell and the flange-shaped member are made of metal, and the flange-shaped member is further coated with zirconium oxide. 5. A regenerative tile structure according to claim 3, wherein the shell has a plurality of circumferentially spaced openings providing a means for introducing combustion air therein.