JPH102509A - Synthetic solid fuel combustion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a combustion device to perform high-efficient combustion of synthetic solid fuel formed of fractional recovery refuse and having a high ash content without leakage of combustion gas and unburnt gas. SOLUTION: A synthetic solid fuel combustion device is formed such that a plurality of air feed holes 2b for combustion are formed in side peripheral walls 1c-1f and a plurality of combustion air feed holes 2a are formed in a hearth 1b and synthetic solid fuel is burnt on the hearth 1b. Plate members 44A and 44B for extruding ash reciprocated and slid along the opening surface of the combustion air feed hole 1b are arranged on the upper surface of the hearth. Further, an ash discharge port 20 to discharge ash extruded by plate members 44A and 44B for extruding ash is formed in a position below a side peripheral wall 1d. A cover member 21 constituted in a manner to be always in an attitude to close the ash discharge port 20 and open the ash discharge port 20 only when the members 44A and 44B for extruding ash are operated is arranged at the ash discharge port 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic solid fuel combustion apparatus, and more particularly, to a synthetic resin which has been disposed of.
The present invention relates to a synthetic solid fuel combustion apparatus that is particularly suitable for burning synthetic solid fuel produced by compression molding of wood waste and paper waste.

[0002]

2. Description of the Related Art Heretofore, in a combustion furnace having a fixed hearth, it has been considered that one problem is to supply combustion air and discharge combustion ash, and several proposals have been made for that purpose. For example, in a combustion furnace of a type in which a solid fuel is charged on a grate to form a fixed bed and burn on the hearth, a rotary stirring means capable of supplying combustion air simultaneously with stirring of the fixed bed is provided. A combustion furnace is known (see Japanese Patent Application Laid-Open No. 62-210505), and high-load combustion is enabled by providing a rotary stirring means capable of supplying air. However, the ash that accumulates on the hearth falls naturally on the furnace bottom through the air holes of the grate, and the air holes are clogged with the ash, which may cause a shortage of supply of primary air for combustion.

In order to effectively remove ash on the grate, the hearth is inclined with respect to the horizontal plane, and a plurality of projections are projected on the hearth to burn on the side walls of the projections. There is known a fixed-bed combustion furnace in which an air inlet is formed, and a pusher for extruding ash having a convex portion loosely fitted to the convex portion is provided so as to reciprocate along the furnace floor. (See JP-A-59-55232). In this combustion furnace, the combustion air is sent from the combustion air inlet formed on the side wall of the projection, so that the combustion efficiency is improved and the ash is easily discharged from the combustion ash outlet by the movement of the pusher. The clogging of the air holes of the grate can be avoided. However, in this type of combustion furnace, the inside of the combustion furnace has a positive pressure due to the balance between the blowing and blowing of the combustion air, but in the above-described combustion furnace, the combustion ash discharge port is in an open state. The combustion gas in the furnace may leak to the outside from the combustion ash discharge port.

[0004] As a pulverized coal combustion furnace which avoids the leakage of combustion gas from the combustion ash discharge port, a sliding plate slidable closely along the upper surface of the hearth is intermittently reciprocated, thereby burning the pulverized coal. In a pulverized coal combustion furnace which crushes clinker generated later and equalizes the thickness of the pulverized coal bed and simultaneously discharges ash from the combustion ash outlet together with the crushed clinker, the clinker and the combustion ash are transferred to a sister tank. It is known that the water passes through the water inside and is discharged to the outside (see Japanese Utility Model Publication No. 5-47928). According to this combustion furnace, the combustion ash discharge port is basically sealed with water, so that the combustion gas does not leak outside.

[0005]

[0005] However, actual fairness 5-4
In the case of the combustion furnace of the type described in JP-A-7928, when the combustion material is pulverized coal, the amount of ash is small compared to the amount of clinker, and since this clinker is heavier than water, Since it sinks under water, there is no particular problem in the emission of combustion ash. However, when a fuel containing a large amount of ash is used, the ash floats on the water, where it absorbs moisture and solidifies, so that it cannot be easily discharged to the outside.

[0006] In recent years, garbage has been separated and collected in each municipality, and the combustible waste (wood waste, paper waste, resin material, etc.) that has been collected is pulverized and then mixed at a fixed rate to obtain solid fuel. In many cases, a so-called synthetic solid fuel is compressed and reduced in volume by a compression molding machine to obtain a so-called synthetic solid fuel, and effective use of the synthetic solid fuel produced in this manner is required. However, since the synthetic solid fuel produced in this manner may generate more combustion ash compared to coal fuel, it can be effectively combusted by the conventional fixed-bed combustion device as described above. It is difficult to achieve this, and there is a demand for the development of a combustion furnace suitable for this kind of synthetic solid fuel.

An object of the present invention is to efficiently burn a synthetic solid fuel, which is expected to emit a large amount of ash after combustion, without leaking combustion gas and unburned gas to the outside as described above. And, more specifically, continuous combustion of synthetic solid fuel produced based on household waste separately collected for resource reuse with high combustion efficiency and for a long time. An object of the present invention is to provide a synthetic solid fuel combustion device capable of being operated.

[0008]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problem by basically providing an ash outlet at a lower portion of a peripheral wall on a combustion furnace side,
This problem has been solved by providing a cover for the discharge hole so that the discharge hole can be opened only when the sliding plate for pushing out the ash is operated. That is, in the present invention, a plurality of combustion air supply holes are provided in the side peripheral wall, and a plurality of combustion air supply holes are provided in the hearth, so that the synthetic solid fuel is burned in the hearth. In the synthetic solid fuel combustion device, an ash pushing plate member that reciprocates and slides along the opening surface of the combustion air supply hole is provided on the hearth upper surface, and further, at a position below the side peripheral wall. Is provided with an ash outlet for discharging the ash extruded by the ash pushing plate member, and the ash discharging port is always in a position to close the ash outlet, and the ash pushing plate member A lid member that opens the ash discharge port only when is operated.

In the present invention, when the ash pushing plate member is not operated, that is, when the ash pushing plate member is retracted to the rear of the furnace, the lid member is appropriately pressurized by its own weight or provided as needed. Further urged by means closes the ash outlet. Therefore, leakage of the combustion gas and the unburned gas from the ash discharge port does not occur. When the ash pushing plate member advances into the furnace along the opening of the combustion air supply hole on the upper surface of the hearth, the ash deposited on the hearth is pushed by the tip of the ash pushing plate member and pushed out to the ash discharge port side. It is.
The lid member opens by an angle corresponding to the pressure received from the extruded ash, and discharges the ash from the ash discharge port to the outside of the furnace. After discharging the required amount of ash, the ash extrusion plate member is retracted. As a result, the lid member is immediately closed, and leakage of the combustion gas and the unburned gas is prevented. The ash extrusion plate member retreats to its original position,
Advance again if necessary. This reciprocating movement is repeated as necessary.

In the present invention, the thickness of the ash extrusion plate member is preferably smaller than the cross-sectional dimension of the synthetic solid fuel used as fuel. Thereby, simultaneously with the extrusion of the ash by the movement of the ash extrusion plate member, the separation of the ash and the unburned portion of the synthetic solid fuel progresses, the ash is pushed out, and the unburned portion remains in the furnace. Higher combustion efficiency is obtained.

[0011] In a preferred aspect of the present invention, the ash extrusion plate member is provided so as to cover only a part of the hearth, and all or a part of the hearth surface which is not covered by the ash extrusion plate member is provided. A second ash-extruding plate member, which is reciprocally slid in a direction crossing the reciprocating sliding direction of the ash-extruding plate member, is further provided. In this aspect, it is not necessary to provide the ash discharge port over the entire side surface of the hearth, and the opening area can be made smaller, so that the leakage of the combustion gas is more reliably prevented. Furthermore, at the time of the pushing action of the ash pushing plate member, the entire hearth can be prevented from being closed by the ash pushing plate member, so that the combustion efficiency does not decrease due to the insufficient supply of the primary combustion air. . Furthermore, by the second ash extrusion plate member,
Since the ash is separated from the burning synthetic solid fuel at the same time as the ash is transferred, the combustion efficiency is definitely improved.

[0012]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a front view, partially in cross section, illustrating an embodiment of a synthetic solid fuel combustion device according to the present invention, showing a state where a lid member is in a closed posture. FIG. 2 is a side view showing the device of FIG. 1 in a partial section viewed from a direction different by 90 °.

As shown in FIGS. 1 and 2, the furnace body A has a ceiling 1a made of a refractory material, a hearth 1b, and four circumferential side walls 1c to 1f, and a combustion chamber S is formed inside. I do. Hearth 1
b is provided with a large number of air holes 2a for supplying primary air for combustion, and two opposing side walls 1c and 1d of the four side walls 1c to f are also provided with air holes 2b for supplying secondary air for combustion. Are provided in large numbers. The other side wall 1e is provided with a burner nozzle 3 as a combustion gas (combustion flame) jet port. Further, the side wall 1f opposite to the side wall 1e where the burner nozzle 3 is located has air directly opening into the combustion chamber S. Supply port 4
Is provided (FIG. 2). The air supply port 4 is connected to a pipe line 51 connected to a combustion air blower 50 described later, and an ignition burner 5 and a frame sensor 5a are arranged in the air supply port 4. The ceiling 1a is provided with a supply port 6 for supplying a fuel, and the fuel supply port 6 is connected to a discharge end side of a screw conveyor 11 connected to the fuel hopper 10 so that the fuel in the fuel hopper 10 The solid fuel 12 passes through the fuel supply port 6 from the screw conveyor 11 and is charged into the combustion chamber S of the furnace body.

The ceiling 1a and four side walls 1c to 1f.
Is covered with an air jacket 7, and the air jacket 7 has a pipe 52 connected to a combustion air blower 50.
Are in communication. The periphery and lower part of the hearth 1b are covered with a water cooling jacket 8 to prevent the hearth 1b from being overheated. The bottom of the water cooling jacket 8 is formed as an air jacket 7 ', and a pipe 52 connected to the combustion air blower 50 communicates with the air jacket 7'. An air hole 2c is also formed in the fuel supply port 6, from which air in the air jacket 7 is supplied as secondary air for combustion. In FIG. 1, M1 is a motor for driving the screw conveyor 11.

At the position of the upper surface of the hearth 1b on the side wall 1d, an ash discharge port 2 extending over the entire width of the combustion chamber S is provided.
0, and the ash outlet 20 is provided as shown in FIG.
A cover member 21 having a size capable of covering the entire surface of the ash discharge port 20 is provided at the tip of the ash through the air jacket 7 and extending beyond the outer wall of the furnace. The discharge port 20 is pivotally connected to a hinge 22 so that the discharge port 20 can be closed. In this embodiment, the lid member 21 is divided into two parts at the center of the ash discharge port 20 in the width direction, and is configured as a first lid member 21A and a second lid member 21B. It can be rocked.

An opening 25 having the same size as the ash discharge port 20 is provided on the side wall 1c opposite to the side wall 1d where the ash discharge port 20 is provided.
The opening 25 also penetrates through the air jacket 7 and reaches the furnace outer wall. As shown in FIG. 1 and FIG.
5, a rotary transfer device 40 including two endless chains 42 wound between a pair of sprockets 41 a and 41 b adjusts the lower surface height of the endless chains 42 to the upper end surface of the opening 25. Two sets are provided in parallel at almost the same position as the height. At the lower surface side of the endless chain 42, a posture in which ash pushing plate members 44A and 44B are fixed to the endless chain 42 at the outer ends thereof by a locking member 43 is attached. The ash extrusion plate member 44
A guide plate 45 is disposed at a position below A and 44B, and a motor M2 for driving the endless chain 42 is attached to the back surface of the guide plate 45. The ash extrusion plate members 44A and 44B are rectangles of the same size, the width is substantially half the width of the opening 25, and the length is longer than the length including the air jacket 7 of the combustion furnace. It is said.

When the motor M2 is driven and the endless chain 42 is rotated in the forward and reverse directions by a control mechanism (not shown), the ends of the ash pushing plate members 44A and 44B are burned. The position (FIG. 1) retracted from the chamber S and the tip extends beyond the ash discharge port 20 and pushes the first lid member 21A or 21B with the tip to open the first lid member 21A or 21B. (FIG. 4b). At this time, as shown in FIGS. 3A and 3B, one ash pushing plate member 44A is in the advanced position and its corresponding first lid member 2
1A is in the open state, the other ash pushing plate member 44B is in the retracted position and the corresponding second lid member 21 is in the retracted position.
It is a preferable embodiment that B is operated by a control mechanism (not shown) in which both are reciprocated out of phase so as to keep the closed state, whereby the air holes 2b formed in the hearth 1b are used for ash extrusion. It is possible to avoid all the blockages by the plate members 44A and 44B and prevent unstable combustion.

A casing 53 is provided outside the lid member 21.
At the lower end of the casing 53, a screw 54 for discharging ash is provided. The discharge side of the ash discharge screw 54 is open to an ash receiver 60 via a pipe 55, and the upper air layer area of the ash receiver 60 is connected to the intake side of the combustion air blower 50 by a pipe 56. doing. Further, a large number of pores 61 are provided near the upper end surface of the ash tray 60.
Is formed, from which air can flow. M3 is a motor for driving the ash discharging screw 54.

Next, the operation of the above-described synthetic solid fuel combustion device will be described. (1) A synthetic solid fuel 12 mainly made of combustible waste such as wood chips, paper waste, and resin material, which is manufactured by using an appropriate manufacturing apparatus (not shown), is put into a fuel hopper 10, and a motor M1 is operated. To rotate the screw conveyor 11,
The fuel 12 is sent into the combustion chamber S. In this case,
The ash pushing plate members 44A and 44B are both set at the retracted positions (retracted positions). Therefore, the first and second lid members 21A and 21B are in the closed posture. (2) The combustion air blower 50 is operated, and the ignition burner 5 is ignited. The fuel of the ignition burner 5 uses heavy oil, kerosene, or the like as an auxiliary fuel.

(3) It is confirmed by the flame sensor 5a that the composite solid fuel 12 in the combustion chamber S has been ignited, and the supply of the auxiliary fuel to the ignition burner 5 is stopped. (4) During combustion, the combustion chamber S is at a positive pressure, and the flame blows out from the burner nozzle 3. The heat of this flame is used as a heat source for a boiler or the like (not shown). However, the first and second lid members 21A, 21B attached to the ash outlet 20
Are in a closed position, and no fuel gas or unburned gas leaks out of the ash discharge port 20. (5) The control mechanism sets the reciprocating movement interval according to the amount of ash generated (depending on the component ratio of the synthetic solid fuel used),
In addition, the rotary transfer device 40 is driven to reciprocate the ash pushing plate members 44A and 44B with their phases being alternately shifted.

(6) By the advance of the ash pushing plate member 44A, most of the ash accumulated on the hearth 1b in front of the ash pushing plate member 44A is scraped out and gradually pushed into the ash discharge port 20 side.
Some are excluded laterally. In the meantime, the synthetic solid fuel 13 burning is also impacted by the ash pushing plate member 44A, so that the ash is shaken off. (7) By being further pushed, the pressing force of the ash acting on the first lid member 21A in front of the ash pushing plate member 44A gradually increases, and finally, the first lid member 21A
Swings into an open state. As a result, the ash starts to be discharged out of the machine from the portion of the ash discharge port 20 corresponding to the first lid member 21A. The ash pushing plate member 44A further advances, and after reaching the most advanced position shown in FIG. At the same time, another ash extrusion plate member 16B
Begins to move forward.

(8) When discharging the ash, half of the ash discharge port 20 in the width direction is closed by the other second lid member 21B, and the side where the first lid member 21A is open is the ash content. And the ash pushing plate member 44A.
Thereby, the combustion gas or the unburned gas hardly leaks. The discharged ash is sent out to the ash receiver 60 by the ash extraction screw 54.

Thereafter, during the continuation of the combustion, the reciprocating movement of the ash pushing plate members 44A, 44B with the phases shifted is repeated. Thereby, the number of air holes 2a closed at a time can be reduced to half of the whole at the maximum, and stable combustion is maintained.

As described above, according to the synthetic solid fuel combustion apparatus of the present invention, the leakage of the combustion gas or the unburned gas from the ash outlet 20 can be avoided. Since the air layer of the ash receiver 60 is connected to the intake side of the combustion air blower 50 through the conduit 56, the leaked combustion gas or unburned gas is not released to the outside air and the combustion chamber S It is blown back to.
FIG. 5 shows another embodiment of the synthetic solid fuel combustion device according to the present invention. FIG. 5 shows a cross section in the same direction as in FIG. 2 of the synthetic solid fuel combustion device according to the first embodiment described with reference to FIGS. 1 to 4, and has the same functions as those in the first embodiment. The fulfilling members have the same reference numerals.

In the example shown in FIG. 5, the lateral width is widened, and the supply port 6 for charging the fuel is provided to be deviated to the left of the combustion chamber S in the figure, and the ash discharge port 20 (in FIG. Not shown)
The ash discharging screw 54 is provided so as to be displaced to the right. That is, the ash discharge port 20 is not provided over the entire width of the combustion chamber S. On the other hand, a second opening 120 is provided over the entire width of the combustion chamber S at a height position of the surface of the hearth 1b on one side wall 1f orthogonal to the side wall on which the ash discharge port 20 is formed. A second rotary transfer device 140 having substantially the same configuration as the rotary transfer device 40 described above is attached to the side of the second opening 120.
The second rotary transfer device 140 includes a second ash pushing plate member 144 similar to the ash pushing plate members 44A and 44B.
A and 144B are attached so as to be able to freely enter and exit the combustion chamber S. The second rotary transfer device 140 operates similarly to the rotary transfer device 40 by a control mechanism (not shown).

According to this embodiment, in the case of a high-load combustion furnace having a large hearth bottom area, the ash discharge port 20 is provided not in the entire side surface of the hearth 1b but in a narrower section. The intended purpose is achieved. Thereby, leakage of the combustion gas or the unburned gas is reliably prevented. Further, when the ash extruding plate members 44A, 44B are pushed out, the area where the hearth surface is closed by the ash extruding plate members is further reduced, so that combustion instability occurs due to an insufficient supply of the primary air for combustion. Can be reliably avoided. Further, the second ash pushing plate members 144A and 144B separate the ash from the burning synthetic solid fuel simultaneously with the movement of the ash, so that the combustion efficiency is reliably improved.

In the present invention, the cover member 21
Is normally in a position to close the ash outlet 20, and if the ash outlet 20 is opened only when the ash pushing plate member 44A or 44B is operated, the shape and size of the ash outlet 20 are The length is arbitrary and there is no particular limitation. The closing position may be achieved and maintained only by the own weight of the lid member, or may be achieved and maintained by an appropriate urging means such as a spring pressing in addition to the own weight.
Below, in the case of obtaining a closed position only by its own weight,
A design example of the lid member 21 will be described by taking an example in which one lid member is used as a whole.

The shape of the ash discharge port 20 is 25 mm × 400 m
m, and the pressure in the furnace at the time of rated combustion is plus 60 mmAq, the pressure P received by the lid member 21 provided at the ash discharge port 20 from the inside of the furnace is P = 60/10000 = 0.006 kgf / cm ² The area S of the lid member 21 which receives the pressure is as follows: S = 2.5 cm × 40 cm = 100 cm ² The thickness of the lid member 21 is 16 mm, and the vertical length is 22 m.
m, and the center height of the hinge 22 is 3 mm, the effect of the lid member weight on the furnace pressure is θ = tan ⁻¹ (8/22) ≒ 20 °. The required mass M is M = P × S / tan θ = 0.006 × 100 / tan20 ° = 1.65 kgf If the safety factor is 1.4, it is 2.3 kgf. Therefore, if a flat steel of 16 mm × 36 mm × 500 mm is used, the weight is about 2.4 kg, so that the leakage of combustion waste or unburned gas from the furnace can be substantially suppressed.

It will be appreciated that if springs are biased in the closing direction, lighter steel can be used.

[0030]

According to the synthetic solid fuel combustion apparatus of the present invention, even when a synthetic solid fuel containing a large amount of ash is burned, the ash can be reliably removed without leaking the combustion gas or the unburned gas outside the apparatus. It can be discharged outside the machine, and high combustion efficiency can be continuously achieved.

[Brief description of the drawings]

FIG. 1 is a front view, partially in section, illustrating an embodiment of a synthetic solid fuel combustion device according to the present invention.

FIG. 2 is an explanatory side view showing a partial cross section of the apparatus of FIG. 1 viewed from a direction different by 90 °.

FIG. 3 is an explanatory plan view with a partial cross section for explaining a moving state of a ash pushing plate member.

FIG. 4 is a partially enlarged cross-sectional view for explaining an open / close state of a lid member.

FIG. 5 is an explanatory side view partially showing a cross section of another embodiment of the synthetic solid fuel combustion device according to the present invention.

[Explanation of symbols]

A: Furnace body, 1a: Furnace ceiling, 1b: Furnace floor, 1c-
1f: furnace side wall, 2a: air hole for primary air supply for combustion, 1b ... air hole for secondary air supply for combustion, 3 ... burner nozzle, 6 ... fuel supply port, 7, 7 '... air jacket , 8 ... water cooling jacket, 10 ... fuel hopper, 11 ...
Screw conveyor, 12: synthetic solid fuel, 20: ash outlet, 21 (21A, 21B): lid member, 22: hinge, 25: opening, 40: rotary transfer device, 41a, 41b
... Sprocket, 42 ... Endless chain, 43 ... Locker,
45: guide plate, 44A, 44B: ash extrusion plate member, 5
0: combustion air blower, 51, 52 ... pipeline, 53 ... casing, 54 ... ash conveyor, 60 ... ash receiver, 61 ...
Pores, M: motor, S: combustion chamber.

Claims (4)

[Claims] A plurality of combustion air supply holes are provided in a side peripheral wall, and a plurality of combustion air supply holes are provided in a hearth, and a synthetic solid fuel is burned in the hearth. A solid fuel combustion device, wherein an ash pushing plate member that reciprocates and slides along an opening surface of the combustion air supply hole is provided on the hearth upper surface, and further, at a position below the side peripheral wall. An ash discharge port for discharging ash extruded by the ash extrusion plate member is provided, and the ash discharge port is always in a position to close the ash discharge port, and the ash extrusion plate member is A synthetic solid fuel combustion device, comprising a lid member that opens the ash discharge port only when activated. 2. The synthetic solid fuel combustion device according to claim 1, wherein said lid member is mounted in the vicinity of said ash discharge port in such a manner as to be swingable with its upper edge side as a pivot point. . 3. The ash extrusion plate member is constituted by a plurality of plate members positioned in parallel with each other, and each of the plate members can reciprocate in different phases. 3. The synthetic solid fuel combustion device according to claim 1, wherein: 4. The ash-extruding plate member is provided so as to cover only a part of the hearth, and all or one portion of the hearth surface that is not covered by the ash-extruding plate member is provided. The ash pushing plate member is further provided with a second ash pushing plate member adapted to reciprocate in a direction crossing the reciprocating sliding direction of the ash pushing plate member. 4. The composite fuel combustion device according to any one of claims 3 to 3.