JPH1073229A - Ash treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the solidification and accumulation of molten slag at the lower end in the direction of inclination of a hearth part while efficiently heating incinerating ash when the ash is melted on the inclined furnace floor part. SOLUTION: An ash treatment apparatus 10 has a channel-shaped hearth part 16 in a combustion chamber 12 and ash is dumped by an ash dumping device 18 from the upper end 16A in the direction of inclination of the furnace floor part 16. The ash on the hearth part 16 is heated and melted efficiently by a first burner and the lower end 16B in the direction of inclination of the hearth part 16 is heated by a second burner 22 thereby keeping the molten slag from being solidified and accumulated at the lower end.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ash treatment device for heating and melting refuse incineration ash and the like to treat it as molten slag.

[0002]

2. Description of the Related Art Ash from incineration of garbage discharged from factories and homes is melted into molten slag, thereby greatly reducing the volume of the ash and scattering harmful metals contained in the ash. In addition, the use of molten and solidified slag as an aggregate in building materials has been attempted.

[0003] As one of such incineration ash melting apparatuses, there is one described in, for example, JP-A-7-273158. The ash treatment device disclosed in Japanese Patent Application Laid-Open No. 7-273158 blows a flame from a burner on ash falling from a hopper, heats and melts the ash, and heats and melts the ash on a hearth portion inclined in the combustion chamber. When the molten slag flows down on the hearth, it is further heated and completely melted by a burner, and from the lower end of the inclined hearth,
The solidified slag is collected by dropping and solidifying into lower water.

[0004]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 7-273 is disclosed.
No. 158 discloses an ash treatment device in which ash is pushed into a cylindrical portion projecting downward into a combustion chamber by a feed screw provided in a hopper, and ash is injected into a flame blown from a burner in the cylindrical portion. However, if the amount of ash in the hopper is not sufficient, there is a problem that the combustion gas blows up from the cylindrical portion into the hopper.

Further, since the volume of the cylindrical portion is small, there is a problem that the flame blown from the burner cannot form a sufficient vortex, and thus the ash may not be sufficiently heated and melted.

[0006] Further, the molten slag flows down along the inclined hearth, but the temperature decreases at the tip (lower end) of the hearth, and solidification and deposition occurs there. However, there is a problem in that the molten slag accumulates thickly on the furnace floor, and in some cases, the molten slag adheres to the hearth and solidifies on the bottom surface where the temperature is low.

Further, in the apparatus for ash treatment as described above, a burner for forming a flame for heating and melting the ash is provided by:
For example, one disclosed in JP-A-6-281114 is used.

In this burner, a nozzle for ejecting fuel is disposed coaxially with the inner tubular member in an inner tubular portion to which combustion air is supplied, and the fuel ejected from the nozzle and the fuel supplied from the inner tubular member are supplied. Is mixed with the air to be blown, and the mixed gas is formed into a conical flow which expands forward by the tip of the conical member, and is disposed outside the conical member with respect to the flow of the air-fuel mixture. A spiral air flow is ejected from the tip of the cylindrical member, and the mixed gas is placed on the spiral air flow and swirled in the combustion chamber to perform combustion.

In the burner as described above, the gas mixture formed by the fuel jetted from the nozzle and the air supplied from the inner cylindrical member is blown to the conical member, so that the outer periphery of the conical member is Liquid fuel adheres,
There is a problem that the concentration of fuel in the air-fuel mixture becomes low, so that sufficiently high-temperature combustion cannot be obtained.

The present invention has been made in view of the above-mentioned conventional problems, and it is not necessary to bring ash and flame into contact with each other in a tubular member in front of the hearth, and the ash can be sufficiently removed on the hearth. It is an object of the present invention to provide an ash processing device which can be heated and melted.

It is another object of the present invention to provide an ash processing apparatus which prevents high-temperature gas from flowing back from the combustion chamber to the hopper even when the ash in the hopper is small.

It is a further object of the present invention to provide an ash treatment apparatus which prevents molten slag from solidifying at the tip of the hearth and accumulating the molten slag on the hearth.

[0013] Another object of the present invention is to provide an ash processing apparatus which can burn fuel efficiently at high temperature in a burner used for heating and melting ash.

[0014]

According to the present invention, there is provided a furnace body forming a combustion chamber, and a molten slag which is disposed in the combustion chamber in a longitudinally inclined manner and is formed by melting ash from a lower end in the inclined direction. A groove-shaped hearth to be flowed down, an ash input device for supplying ash to an upper end of the hearth in an inclined direction, and a flame provided to the combustion chamber and blowing a flame to a middle part of the hearth in a longitudinal direction. The above object is achieved by an ash treatment device having a first burner and a second burner that blows a flame to an end of the hearth where the molten slag flows down.

Since the hearth has a groove shape, a flame from the first burner is applied to the ash flowing there.
It flows along the groove-shaped bottom of the hearth and efficiently heats and melts the ash on the hearth. Further, since the flame is blown to the end of the hearth by the second burner, the molten slag is solidified at the tip (lower end) of the hearth, and the molten slag is deposited on the hearth. To prevent

According to a second aspect of the present invention, in the first aspect of the present invention, the bottom surface of the hearth portion has a concave arc shape.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the ash input device includes an ash input pipe linearly extending from the upper end of the hearth in the inclined direction to the outside of the combustion chamber; An ash hopper that is connected to the input pipe outside the combustion chamber and drops ash into the ash input pipe, and is arranged coaxially with the ash input pipe;
And a pusher for extruding the ash dropped from the ash hopper into the ash input pipe from the ash input pipe onto the hearth.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the central axes of the ash input pipe and the hearth are substantially aligned in the width direction.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, at least one of the first and second burners surrounds a fuel injection nozzle and the fuel injection nozzle coaxially. A cylindrical member having a mixed fluid injection port located at a front end thereof in the injection direction of the fuel injection nozzle, and an air pipe to which combustion air is supplied from a base end side, and coaxially surrounding the air pipe; And an output opening located at the front end in the ejection direction of the mixed fluid ejection port, and a proximal side surface formed outside the air pipe so as to form a spiral flow toward the output opening. And a swirling flow forming pipe to which air is supplied from.

According to a sixth aspect of the present invention, in the fifth aspect of the invention, the mixed fluid injection port is a tapered opening that expands forward.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ash processing apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

As shown in FIGS. 1 to 4, an ash processing apparatus 10 according to an embodiment of the present invention includes a furnace body 14 forming a combustion chamber 12 and a longitudinally inclined inside of the combustion chamber 12. A groove-shaped hearth portion 16 for disposing molten slag formed by melting ash from a lower end 16A in the inclined direction, an ash input device 18 for supplying ash to an upper end 16B in the inclined direction of the hearth portion 16, And first and second burners 20 and 22 disposed on the ceiling 15 of the furnace main body 14 above the combustion chamber 12, wherein the first burner 20 is located in the middle of the hearth 16 in the longitudinal direction. The second burner 22 is set to blow the flame toward the lower end 16A of the hearth 16 in the inclined direction.

As shown in FIGS. 2 and 3, the hearth 16 has a concave arc-shaped bottom surface 17, and crosses the combustion chamber 12 at an inclination of about 20 degrees in the left-right direction in FIG.
It extends linearly, and the lower end 16A in the inclined direction is arranged facing a slag drop port 24 formed vertically downward.

The ash input device 18 has a straight ash input pipe 26 connected to the upper end 16B of the hearth 16 in the inclined direction through the wall of the furnace body 14.

The ash input pipe 26 has a rectangular cross section, and its longitudinal direction is, as shown in FIG.
The center axis is aligned with the hearth 16 so that the center axis coincides with the center axis of the hearth 16 in the width direction. In addition, the ash input pipe 26 is displaced above the hearth 16 in the vertical direction.

The ash input device 18 is provided with the ash input pipe 26.
And an ash hopper 28 connected from above near the upper end of the ash input pipe 26 outside the furnace;
A pusher 30 arranged coaxially with the ash hopper 6 and capable of extruding ash flowing from the lower end of the ash hopper 28 into the ash input pipe 26 toward the upper end 16B in the inclined direction of the hearth 16. It is configured.

Reference numeral 32 in FIGS. 1 to 4 denotes a cooling water jacket covering the entire outside of the furnace body 14, and reference numeral 32 in FIGS.
A is a cooling water inlet, 32B in FIGS. 2 and 3 is a cooling water outlet, 34 is an observation window for observing the inside of the combustion chamber 12, especially near the lower end 16A in the inclined direction of the hearth 16, and FIGS. Reference numeral 36 indicates a hot air outlet.

A cooling water tank 40 having a screw 38 for discharging solidified slag is disposed below the slag drop port 24.

Further, the hearth portion 16 in the furnace body 14 is provided.
Below, is provided a smoke pool 42 which communicates with the upper portion of the cooling water tank 40 through two communication ports 40A, and as shown in FIG. The water vapor passes through a smoke exhaust port 44, passes through a heat exchanger 46, reaches a secondary combustion furnace 48, where the unburned portion is subjected to secondary combustion, and is discharged to the outside.

As shown in FIG. 3, primary combustion air is introduced into the heat exchanger 46 from an air inlet 46A.
Preheated air heated by heat exchange with flue gas and water vapor generated by the primary combustion is taken out from the air outlet 46B on the opposite side, and the preheated air is supplied from the air outlet 46B to the hot air blowing provided in the combustion chamber 12. The gas is blown out from the outlet 36 into the combustion chamber 12.

Next, referring to FIG. 5 and FIG.
And the second burners 20 and 22 will be described.

The first and second burners 20, 22
Have the same shape, the first burner 20 will be described, and the description of the second burner 22 will be omitted.

The first burner (hereinafter, burner) 20 is
A fuel injection nozzle 52, a cylindrical member surrounding the fuel injection nozzle 52 coaxially and having a mixed fluid injection port 54 at a distal end thereof at a position ahead of the fuel injection nozzle 52 in the injection direction; An air pipe 56 to which combustion air is supplied from the side, and an air pipe 56 disposed coaxially around the air pipe 56, the tip of which is an output opening 58 in the injection direction of the mixed fluid injection port 54, and the air pipe 56. The swirl flow forming pipe 6 to which air is supplied from the outer surface on the proximal end side so as to form a spiral flow toward the output opening 58 outside
0.

The fuel injection nozzle 52 is provided at the distal end of a fuel pipe 62 inserted and fixed in the air pipe 56 from the base end thereof. Fuel from a fuel tank 63 is supplied to the fuel pipe 62 by a fuel pump 64 via a valve 66 under pressure.

The air pipe 56 is supplied with compressed air from an air pump 68 via a valve 70 to an air port 56A formed in a base peripheral wall.

The swirling flow forming pipe 60 has a portion corresponding to a substantially intermediate position in the axial direction of the air pipe 56,
A blow pipe 72 is connected to the center of the air pipe 56 offset from the side.
2. By supplying the compressed air from the air pump 74, a swirling flow is formed along the outer circumference of the air pipe 56.

Here, the air pipe 56 has a multi-stage structure, and the tip 5 having the mixed fluid injection port 54 at the tip is provided.
5 and a plurality of module pipes 56B except for the base end portion.
Can be connected as necessary to adjust its axial length. Reference numeral 57A in FIG. 5 denotes a male thread portion formed at the tip of each module pipe 56B, and 57B denotes each module pipe 5 so as to be screwed into the male thread portion 57A.
6B and a screw portion formed on the base end side of the distal end tip 55 are shown.

As shown in the enlarged view of FIG. 6, the mixed fluid injection port 54 is formed in a tapered shape that expands forward, whereby the mixed fluid of fuel and air is diffused from the mixed fluid injection port 54. It is to be injected while doing.

Next, the process of melting the ash by the ash processing apparatus 10 will be described.

With the first burner 20 and the second burner 22 ignited and the flame blown into the combustion chamber 12 and preheated, the ash falling from the ash hopper 28 into the ash inlet pipe 26 is pushed by the pusher 30. , The upper end 1 of the hearth section 16 in the inclination direction
Extrude on 6B.

In the first burner 20 and the second burner 22, when the fuel injected from the fuel injection nozzle 52 is mixed with air in the air pipe 56 and is blown into the combustion chamber from the mixed fluid injection port 54. The air flows into the combustion chamber 12 on the air flow supplied from the swirling flow forming pipe 60.

In the swirling flow forming pipe 60, since the center axis of the blowing pipe 72 is offset from the air pipe 56, the compressed air supplied from the air pump 74 forms a swirling flow along the periphery of the air pipe 56. The mixed fluid injected from the mixed fluid injection port 54 is blown into the combustion chamber 12 while swirling on the swirling flow. The ignition of the mixed fluid is performed by the mixed fluid injection port 5
This is performed near the exit 4.

Although the size of the hearth section 16 in the width direction is considerably larger than that of the mixed fluid injection port 54, since the mixed fluid injection port 54 is formed in a tapered shape expanding forward, a flame is formed. Radiates widely, and the flame reaches so as to cover a considerable portion of the hearth 16 in the longitudinal direction and the width direction.

In particular, since the bottom of the hearth portion 16 has a concave arc-shaped bottom surface 17, the flame blown from the first burner 20 causes the hearth portion 16 to extend along the concave arc-shaped bottom surface 17. The ash on the hearth 16 is sufficiently heated and melted during the flow in the width direction and the longitudinal direction.

The ash is heated and melted on the hearth 16 to form molten slag. When the ash reaches the lower end 16 A in the inclined direction of the hearth 16, the flame of the first burner 20 does not reach and the hearth 16 is cut off. Here, the molten slag is easily cooled and solidified because it is easily radiated downward, but here, the flame from the second burner 22 is blown, so that the molten slag does not accumulate on the hearth 16. , Falls into the cooling water tank 40 through the slag drop port 24.

The molten slag dropped into the cooling water tank 40 is
It is solidified by cooling and crushed finely because the cooling is instantaneous. The finely crushed solid slag is discharged to the outside by the screw 38 and used as concrete aggregate or the like.

When the molten slag is cooled by the water in the cooling water tank 40, a large amount of steam is generated. Above the cooling water tank 40, the smoke generated in the combustion chamber 12 and the high-temperature combustion gas flow down and flow out into the sump 42 together with the steam.

The hot gas containing smoke and water vapor flowing out to the sump 42 passes through a heat exchanger 46 from a smoke outlet 44 and
It reaches the next combustion furnace 48, where it is completely burned by the secondary combustion air and discharged to the outside.

After the outside air is introduced into the heat exchanger 46 from the air inlet 46 and heated by heat exchange with the high-temperature gas, the heat exchanger 46 passes through the air outlet 46B, and from the hot air outlet 36 of the combustion chamber 12 to the combustion chamber 12. The inside of the furnace 12 is blown out to improve the heating efficiency of the ash on the furnace body 14.

In the ash treatment apparatus 10, the ash in the ash hopper 28 once falls into the ash input pipe 26 and is then pushed out onto the hearth 16 by the pusher 30, so that even when the amount of ash is small, The input pipe 26 can be closed by the ash, so that the combustion gas in the combustion chamber 12 does not flow back to the ash hopper 28.

Since the hearth section 16 and the ash input pipe 26 are arranged so that their central axes coincide with each other in the width direction, the ash input by the pusher 30 is smoothly transferred to the hearth section 16. Is done.

Further, since the hearth portion 16 has the concave arcuate bottom surface 17, the flame from the first burner 20 passes through the hearth portion 16 along the concave arcuate bottom surface 17 in the width direction and the longitudinal direction. Since it flows in the direction, the contact time between the flame and the ash becomes longer, and the ash can be sufficiently heated and melted.

The hearth section 16 may be a groove having a bottom shape other than an arc shape. For example, it may be V-shaped or concave-shaped. However, in these cases, the sprayed flame flows smoothly in the longitudinal direction, but it may be difficult to form a flow in the width direction.

Further, since a part of the flame from the first burner 20 flows down along the inclined hearth 16 or the second burner 22 also blows the flame in the same direction, the combustion chamber 12 The ash can be heated and melted at a high temperature by forming a strong vortex in the fuel and efficiently burning the fuel.

In particular, the first and second burners 20, 22
Is mixed with the swirling flow of air generated by the swirling flow forming pipe 60 and is radiated while diffusing into the combustion chamber 12 because the mixed fluid injection port 54 is formed in a tapered shape expanding forward. The ash on the hearth 16 can be efficiently heated.

In the ash processing apparatus 10, the first
The second burner 20 and the second burner 20 each have a mixed fluid injection port 54 that expands forward, but the present invention is not limited to this, and at least the first burner 20 has a tapered mixed fluid. What is necessary is just to have the injection opening 54. Regarding the second burner 22, the lower end portion 16B of the hearth portion 16 is provided.
Since it is only necessary to heat the gas in a concentrated manner, there is a case where it is not necessary to greatly diffuse the escaping flame.

[0057]

According to the present invention, as described above, the ash can be efficiently melted, the combustion gas blows out of the furnace, and the molten slag solidifies and deposits on the furnace floor. It has an excellent effect that it does not occur.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an ash processing apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is a sectional view taken along the line IV-IV in FIG.

FIG. 5 is a sectional view showing a burner used in the ash processing device.

FIG. 6 is an enlarged sectional view showing a main part of the burner;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Ash processing apparatus 12 ... Combustion chamber 14 ... Furnace main body 16 ... Furnace floor part 16A ... Inclination lower end 16B ... Inclination upper end 17 ... Concave arc-shaped bottom surface 18 ... Ash input device 20 ... First burner 22 ... Second Burner 26 ... Ash input pipe 28 ... Ash hopper 30 ... Pusher 52 ... Fuel injection nozzle 54 ... Mixed fluid injection port 56 ... Air pipe 58 ... Output opening 60 ... Swirl flow forming pipe

Claims (6)

[Claims] 1. A furnace main body forming a combustion chamber, and a groove-shaped hearth section disposed in the combustion chamber at an inclination in a longitudinal direction and for flowing a molten slag formed by melting ash from a lower end in the inclination direction. An ash input device for supplying ash to an upper end of the hearth in the inclined direction, a first burner provided in the combustion chamber and blowing a flame to a middle portion in a longitudinal direction of the hearth, A second burner for blowing a flame to an end of the floor where the molten slag flows down. 2. The method according to claim 1, wherein a bottom surface of the hearth portion is
An ash processing device having a concave arc shape. 3. The ash input device according to claim 1, wherein the ash input device is connected to the ash input tube outside the combustion chamber, the ash input tube extending linearly from the upper end of the hearth in the inclined direction to the outside of the combustion chamber. An ash hopper for dropping ash into the ash input pipe, and an ash disposed coaxially with the ash input pipe, and the ash dropped from the ash hopper into the ash input pipe from the ash input pipe to the hearth section. An ash processing device, comprising: a pusher that extrudes upward. 4. The ash processing apparatus according to claim 3, wherein the central axes of the ash input pipe and the hearth are substantially aligned in the width direction. 5. A fuel injection nozzle according to claim 1, wherein at least one of said first and second burners is coaxially surrounding said fuel injection nozzle and said fuel burner is provided at a tip thereof. A cylindrical member provided with a mixed fluid injection port located in the forward direction of the injection direction of the injection nozzle, and an air pipe to which combustion air is supplied from a base end side, which is disposed coaxially around the air pipe, and has a distal end. An output opening located in the ejection direction of the mixed fluid ejection port, and air is supplied from the side face on the proximal end side so as to form a spiral flow toward the output opening outside the air pipe. And a swirling flow forming pipe. 6. An ash processing apparatus according to claim 5, wherein said mixed fluid injection port is a tapered opening expanding forward.