JP3486385B2 - Waste dry feeder - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is directed to the incineration of municipal waste and industrial waste, the ash contained in the waste is melted by the heat of incineration, and the boiler feed water is heated to construct an aggregate for construction or the like. , And a system for producing steam for power plants, etc., a fluidized bed combustion furnace or a thermal fluidized medium in a pyrolysis furnace is refluxed, and the heat is used to dry and pulverize waste to pulverize the fluidized bed furnace. The present invention relates to a device for supplying and drying wastes.

[0002]

2. Description of the Related Art Municipal solid waste and industrial waste are incinerated, and the incineration heat melts and cools the ash contained in the waste to obtain building aggregates, etc., and further produces steam for power generation plants, etc. In the above system, conventionally, the solid waste to be supplied to the fluidized bed type pyrolysis furnace is crushed to an appropriate size and supplied to the upper space of the fluidized bed. Alternatively, JP-A-10-8964
8 is equipped with a fluidized bed type drying furnace to supply the EGR of about 150 ° C. supplied through the diffuser plate and the hot fluidized sand circulated from the char combustion furnace to dry and dry the waste. The EGR and the hot fluidized sand are fed to the fluidized bed of the pyrolysis furnace by gravity from the drying furnace and the twin-screw horizontal stirring and conveying apparatus to stir and mix the waste and sand mixture. An apparatus is disclosed in which waste is dried while being sent by feeding, and the dried waste / sand mixture is gravity fed to a pyrolysis furnace.

[0003]

The calorific value of waste such as municipal solid waste varies depending on the type of waste, but the water content in the waste has a great influence. Water has a large latent heat of vaporization, and the specific heat of steam exceeds twice that of air and carbon dioxide.
When the water content is high, the amount of heat generated by the waste is small and the temperature of the combustion gas is low, which may make it difficult to operate the device that uses the temperature of the combustion gas. Further, if wastes having different water contents are mixed, the temperature variation of the combustion gas due to the combustion of the wastes becomes large, which makes it difficult to stably operate the apparatus using the temperature of the combustion gas. In particular, a device that performs thermal decomposition of waste in a fluidized bed type pyrolysis furnace and melts ash with high-temperature gas produced by burning the pyrolysis gas in an ash melting furnace to form slag requires a large amount of pyrolysis gas. It

Therefore, in such an apparatus, it is necessary to sufficiently dry the waste and supply it to the pyrolysis furnace. JP-A-1
The waste dry supply device disclosed in 0-89648 is
In the fluidized bed type drying furnace, the waste is pulverized and mixed with the fluidized sand quickly and sufficiently, and the twin-screw type stirring and conveying device is not able to pulverize quickly and sufficiently. Therefore, the drying device had to be large to some extent.

Further, when the waste is supplied to the upper space of the fluidized bed, in the case of solid waste, the shape of the waste is irregular and the supply amount is likely to fluctuate, and light materials such as vinyl are free. Scattered on the board and mixed with the generated gas to cause clogging of the nozzle that supplies the generated gas to the ash melting furnace,
Since the pressure in the furnace into which the waste is put is higher than the atmospheric pressure, there is a problem that gas in the furnace leaks when supplying the waste into the furnace. In view of the above-mentioned problems, the present invention provides a waste drying and supplying device which is small and compact and can be supplied to a fluidized bed furnace in a state where waste is sufficiently crushed and uniformly mixed with fluidized sand. To aim.

[0006]

The invention according to claim 1 is
A supply port for supplying waste and a heat fluid medium is provided on the upper surface on one end side of the outer peripheral surface of a casing that rotatably supports two rotating shafts having a plurality of feed paddles and stirring paddles, and the other end of the outer peripheral surface is provided. A discharge port is provided on the lower side surface, and the feed paddle is fixed to the rotary shaft near the supply port to mainly feed the waste and the heat fluid medium to the discharge port side. It is fixed to the shaft near the discharge port and mainly agitates, pulverizes and mixes the waste and the heat fluid medium, and pulverizes the waste material supplied from the supply port while drying it by the heat of the heat fluid medium. And a drying feeder for forming a uniform mixture with the heat fluid medium and sending the mixture to the discharge port.

According to this invention, the waste introduced from the supply port of the dry feeder has a small inclination angle of the paddle surface fixed to the rotary shaft near the supply port with respect to the direction perpendicular to the rotary shaft, that is, By a plurality of feed paddles having a small stagger angle, the mixture is agitated and mixed with the high temperature fluidized sand that has been refluxed from the fluidized bed combustion furnace supplied from the supply port, and is sent toward the discharge port of the drying feeder and sent. According to this, the waste is dried by the heat of the fluidized sand.

As the waste is dried, it is more likely to be crushed by the mechanical impact received from the paddle, and the smaller the crushed and crushed pieces are, the smaller the bulk becomes. Therefore, the feeding speed becomes slower as it approaches the discharge port of the drying feeder. Is good. When the waste proceeds from the supply port to the discharge side to some extent,
The waste that has been dried has a large inclination angle of the paddle surface fixed to the rotation shaft near the discharge port with respect to the direction perpendicular to the rotation axis, that is, it is large due to a plurality of paddles having a large stagger angle and a small feeding function. As it is impacted and crushed into small pieces, and the surface area of the waste increases, the contact area with the hot fluid sand increases and it becomes easier to dry. When the waste reaches the discharge port, it becomes a state in which the finely crushed waste and the fluidized sand whose temperature has dropped due to heat exchange with the waste are uniformly mixed and discharged from the discharge port. Supplied to the place.

The invention according to claim 2 further includes a second feeder which is disposed below the drying feeder and which is connected to the discharge port of the drying feeder and which supplies the homogeneous mixture to the fluidized bed furnace. At the outlet of the dry feeder, the mixture of the finely crushed waste and the fluidized sand whose temperature has been lowered by heat exchange with the waste is uniformly mixed, It flows down to a second feeder whose inlet is connected to and is supplied to the fluidized bed furnace by the feeder.
The invention according to claim 3 is characterized in that the front end side of the paddle of the drying feeder is formed narrower than the root side,
When a string-like waste material is entangled with the paddle, it is slid toward the tip of the paddle so that it can be easily removed.

According to a fourth aspect of the present invention, the discharge port of the second feeder, which is disposed below the dry feeder and is connected to the discharge port of the dry feeder and supplies the homogeneous mixture to the fluidized bed furnace, is fluidized. It is characterized in that it is installed so as to face the fluidized bed of the bed furnace, and the waste that has been dried and crushed into small pieces is pushed into the fluidized bed while being uniformly mixed with the fluidized sand. It is possible to almost completely prevent gas leakage from
Moreover, the mixing of the waste material into the fluidized bed is accelerated so that the thermal decomposition and combustion become uniform, and the thermal decomposition and combustion products with stable calorific value can be obtained.

According to a fifth aspect of the present invention, the discharge port of the second feeder, which is disposed below the dry feeder and is connected to the discharge port of the dry feeder and supplies the homogeneous mixture to the fluidized bed furnace, is fluidized. It is mounted so as to face the upper space of the fluidized bed of the floor furnace, and the connection between the inlet of the homogeneous mixture and the outlet of the drying feeder in the second feeder and to the second feeder. Since the homogeneous mixture is filled in the section and has a sealing effect, there is no gas leakage even when the waste is supplied to the space above the fluidized bed. Further, since the waste material, which is sufficiently dried and crushed into small pieces, is charged in a state of being uniformly mixed with the fluidized sand, vinyl cloth pieces and the like are not scattered.

According to a sixth aspect of the present invention, the uniform mixture discharged from the drying feeder is supplied to the space above the fluidized bed of the fluidized bed furnace, and the gas in the fluidized bed furnace is the dry material. To prevent leakage through the feeder,
The passage resistance of the homogeneous mixture between the drying feeder discharge port and the inlet of the fluidized bed furnace is increased to some extent so that the drying feeder always extrudes the homogeneous mixture and the drying. Balance with the feeding force of the feeder.
Further, the height difference between the uniform mixture charging port of the fluidized bed furnace and the drying feeder is made as large as possible to increase the sealing effect due to the head difference. Since the uniform mixture is a mixture of the dried and crushed waste and the sand, it is quite dense and the seal can be easily secured. Further, since the waste material, which is sufficiently dried and crushed into small pieces, is put in in a state of being uniformly mixed with the fluidized sand, vinyl cloth pieces and the like are not scattered.

According to a seventh aspect of the present invention, the second feeder is a screw conveyor type second feeder, and a uniform mixture of the dried and crushed waste and the fluidized sand is screwed. Since it is supplied to the fluidized bed furnace at a constant flow rate by the conveyer, waste with a small variation in the calorific value is supplied at a constant flow rate, and stable pyrolysis furnace and combustion furnace operations can be easily performed.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the embodiments shown in the drawings. However, unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. described in this embodiment are not intended to limit the scope of the present invention thereto but merely as examples. FIG. 1 is a cross-sectional view showing the structure of a waste drying and feeding device according to a first embodiment of the present invention, (A) is a vertical cross-sectional view, and (B) is ZZ in (A).
A cross section is shown. 2 is an enlarged view of the drying feeder in FIG. 1, (A) is a vertical sectional view, (B) is a sectional view taken along line XX in (A),
(C) shows the YY cross section in (A). FIG. 3 shows a case where the paddle shape in FIG. 2A is the shape of the second embodiment.

In FIGS. 1 and 2, the waste material supplied from the supply port 11 of the drying feeder 10 through the inlet duct 2 and the heat fluid medium recirculated from the fluidized bed furnace are rotated by a motor 7. The plurality of paddle shafts 4 and 4 ′ are fed toward the discharge port 12 side by a plurality of feed paddles 5 fixed at axial intervals. Reference numeral 1 is a casing, 3 is an outlet duct, and 8 is a paddle shaft bearing. Paddle shaft 4,
The 4'paddles are rotated to engage each other. The waste and the heat fluid medium may be supplied from separate supply ports.
The waste is mixed with the heat-fluid medium as it is sent by the feed paddle 5, dried by the heat of the heat-fluid medium to reduce its volume, and stirred and mixed with the heat-fluid medium by the stirring paddle 6. Since the waste becomes easier to be pulverized as it is dried, it is pulverized into small pieces by the stirring paddle 6 while being uniformly mixed with the fluid medium to promote the drying, and is sent to the discharge port 12. Moisture gas 9 generated by drying the waste is guided to the secondary combustion furnace arranged in the downstream of the gas flow generated by the pyrolysis furnace, and the odor in the moisture gas 9 is high at the high temperature in the secondary combustion furnace. Be disassembled.

The feed speed varies depending on the inclination angle of the feed paddle 5 fixed to the paddle shaft 4 with respect to the direction perpendicular to the paddle shaft 4, that is, the size of the stagger angle a. In FIG. 2 (A),
The stagger paddle 6 has a stagger angle a of 90 ° and is not provided with a feeding function, but the stagger paddle and the stir paddle may be arranged such that the stagger angle a is sequentially changed to appropriately distribute the feed function and the stirrer function. In FIGS. 2 (B) and 2 (C), the paddles are arranged at 90 ° intervals in four directions, but may be in three directions or five directions other than the four directions. The front shape of the paddle in FIG. 2 is rectangular, but as shown in FIG.
The front shapes of a and 6a may be trapezoidal. Alternatively, the tip of the paddle may be narrower than the root. String-shaped waste may be entangled with the paddle during the feeding or stirring of the waste, and if the paddle shape is narrow toward the tip, the entangled string-like material will slide toward the tip of the paddle and become easy to come off. .

The second feeder 20 is the dry feeder 10.
Connected via the outlet duct 3 below
A uniform mixture of the dry waste and the fluidized medium that has been crushed into small pieces that has flowed through the opening 22 of the pyrolysis furnace 30 is driven at a constant speed by a screw 21 that is driven to rotate by a motor 23.
To the fluidized bed 31. At that time, a uniform mixture of the waste material and the fluidized medium in the second feeder 20 seals the in-furnace fluidized bed. However, since the homogeneous mixture has a considerably high density, it is against a high-temperature in-furnace fluidized medium. Has a sufficient sealing effect. The second feeder may be, for example, a pusher other than the screw conveyor.

FIG. 4 shows an embodiment in which the solid waste treatment system is equipped with the waste drying and feeding device of the present invention. In the processing system, the pyrolysis gas, char, and ash 61 generated in the fluidized bed type pyrolysis furnace 52 are guided to the melting furnace 53 and burned, and the combustion heat collects the dust in the dust collector 58 to the melting furnace 53. About 14 ash in the fly ash 63 and the pyrolysis gas char ash 61 produced in the pyrolysis furnace 52 are introduced.
It is melted at 00 ° C. to form slag 64, and the slag flows down into the slag water tank 60 to obtain water-cooled slag used for building aggregate or the like. The combustion gas discharged from the melting furnace 53 is the secondary combustion furnace 5
4 is completely combusted, and the combustion exhaust gas is superheated with steam by a boiler or super heater 72, and then by the air heater 57, the melting furnace 5
3 and the combustion air 82 supplied to the thermal decomposition furnace 52 are heated, and are discharged into the atmosphere through the dust collector 58. The walls of the melting furnace 53 and the secondary combustion furnace 54 are water-cooled wall boilers 70.
And 71. Moisture gas 83 generated by drying the waste is guided to the secondary combustion furnace 54, and the high temperature in the secondary combustion furnace 54 decomposes the odor in the humidity gas 83.

When the second feeder 20 of the present invention is included, a waste drying and supplying device is attached to the pyrolysis furnace 52,
A uniform mixture of the dried and crushed waste and the fluidized sand is supplied to the fluidized bed of the pyrolysis furnace 52 through the screw type second feeder 20. In order to prevent sand in the fluidized bed of the pyrolysis furnace 52 from entering the second feeder 20, the feeder 20 should be filled with the homogeneous mixture without any gaps. The homogeneous mixture formed by the waste is thoroughly dried,
Since it is finely crushed and uniformly mixed with sand, it is possible to fill the inside of the second feeder 20 without any gap,
Excellent sealing property. In order to fill the second feeder with the homogeneous mixture, it is necessary that the drying feeder 10 always pushes the homogeneous mixture into the second feeder 20, which is the second feeder. It is adjusted by the balance between the feeding speed of 20 and the feeding force of the drying feeder 10. The delivery force of the dry feeder 10 is adjusted by the stagger angle of the paddle as described above.

FIG. 5 shows another embodiment in which the solid waste treatment system is equipped with the waste drying and feeding device of the present invention. 4 is different from FIG. 4 in that a drying / feeding device for a waste material including a second feeder 20 is installed so that the homogeneous mixture is supplied to a space above the fluidized bed of the pyrolysis furnace 52. is there. Since the gas pressure in the pyrolysis furnace 52 is slightly higher than atmospheric pressure and the second feeder 20 faces the space in the pyrolysis furnace 52, gas sealing is more difficult than in the embodiment of FIG. However, as described above, the homogeneous mixture filling the second feeder 20 is quite dense and fills the outlet duct 3 of the drying feeder 10 connecting the second feeder 20 and the drying feeder 10. The homogeneous mixture can have a height head,
Gas sealing is easy. Also in this case, it is necessary to sufficiently balance the supply speed of the second feeder 20 and the delivery force of the drying feeder 10.

FIG. 6 shows still another embodiment in which the solid waste treatment system is equipped with the waste drying and feeding device of the present invention. The difference from FIG. 5 is that there is no second feeder,
That is, the discharge duct 3 of the drying feeder 10 communicates with the space above the fluidized bed of the pyrolysis furnace 52 via the duct 25. In this case, the duct resistance of the duct 25 is increased to some extent so that the dry feeder 10 always pushes out the mixture, but the outlet duct 3 of the dry feeder 10
It is better to make the length as long as possible to obtain the sealing effect by the height head.

[0022]

As described above, according to the present invention,
The heat and fluid medium heated to a high temperature in the fluidized bed furnace and the waste are mixed and stirred to efficiently dry and pulverize the waste to form a uniform mixture of the pulverized and fragmented dry waste and the fluidized medium. Since it can be sent to the fluidized bed furnace at a constant speed, waste with a small calorific value variation is supplied to the furnace at a constant flow rate, which enables stable and stable operation of the fluidized bed furnace. Therefore, it is possible to provide a small-sized and compact solid waste drying and supplying device that does not leak gas in the furnace when supplying waste and does not require a separate heat source for drying.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a waste drying / feeding device according to a first embodiment of the present invention, (A) is a vertical sectional view, and (B) is a ZZ sectional view in (A).

2 is a schematic structural diagram of the drying feeder in FIG. 1, (A) is a vertical sectional view, (B) is an XX sectional view in (A), and (C) is YY in (A). FIG.

FIG. 3 is a schematic structural diagram of a drying feeder when the paddle shape of the drying feeder according to the present invention is the shape of the second embodiment.

FIG. 4 is a diagram showing an example in which the waste drying and supplying apparatus according to the embodiment of the present invention is applied to a thermal decomposition furnace in a solid waste treatment system.

FIG. 5 is a diagram showing another embodiment in which the waste drying and supplying apparatus according to the embodiment of the present invention is applied to a thermal decomposition furnace in a solid waste treatment system.

FIG. 6 is a view showing still another embodiment in which the drying and feeding apparatus for waste according to the embodiment of the present invention is applied to a thermal decomposition furnace in a solid waste treatment system.

[Explanation of symbols]

1 casing 2 entrance duct 3 exit duct 4, 4'paddle shaft 5 Feed paddle 6 stirring paddles 7 motor 8 bearings 9 Moisture gas 10 Dry feeder 11 Supply port 12 outlet 20 Second feeder 21 screw 22 Fluidized bed opening 23 motor 30 Pyrolysis furnace 31 fluidized bed

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshinori Terasawa 1-8-1 Sachiura, Kanazawa-ku, Yokohama-shi 1 Mitsubishi Heavy Industries, Ltd. Yokohama Research Laboratory (72) Atsushi Sato 1-8-1, Sachiura, Kanazawa-ku, Yokohama Mitsubishi Heavy Industries (56) Reference JP 49-65669 (JP, A) JP 57-56096 (JP, A) JP 54-113974 (JP, A) JP 8-327039 ( JP, A) JP 55-104659 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F23G 5/44 ZAB F23G 5/033 ZAB F23G 5/04 ZAB

Claims (7)

(57) [Claims] 1. A supply port for supplying a waste material and a heat fluid medium is provided on an upper surface on one end side of an outer peripheral surface of a casing in which two rotary shafts each having a plurality of feed paddles and a stirring paddle are rotatably supported. A discharge port is provided on the lower surface on the other end side of the outer peripheral surface, and the feed paddles are fixed to the respective rotation shafts near the supply port to mainly feed the waste and the heat fluid medium to the discharge port side. The stirring paddles are fixed to the respective rotating shafts near the discharge port, and mainly perform stirring, crushing, and mixing of the waste and the heat fluid medium, and the waste supplied from the supply port is A drying and feeding device for waste, comprising a drying feeder for pulverizing while drying by the heat of the heat fluid medium to form a uniform mixture with the heat fluid medium and sending it to the discharge port. 2. The waste according to claim 1, further comprising a second feeder disposed below the drying feeder and connected to the discharge port to supply the homogeneous mixture to a fluidized bed furnace. Drying and supplying device for materials. 3. The waste drying and supplying apparatus according to claim 1, wherein the tip end side of the paddle of the drying feeder is formed narrower than the root side. 4. The discharge port of a second feeder, which is arranged below the drying feeder and is connected to the discharge port and supplies the homogeneous mixture to the fluidized bed furnace, faces the fluidized bed of the fluidized bed furnace. The drying and feeding device for waste according to claim 2, wherein the drying and feeding device is provided as described above. 5. The discharge port of a second feeder, which is disposed below the drying feeder and is connected to the discharge port and supplies the homogeneous mixture to the fluidized bed furnace, is located in the space above the fluidized bed of the fluidized bed furnace. The waste drying and supplying device according to claim 2, wherein the drying and supplying device is disposed so as to face each other. 6. The apparatus for drying and supplying waste according to claim 1, wherein the uniform mixture discharged from the dry feeder is supplied to a space above a fluidized bed of a fluidized bed furnace. 7. The second feeder is a screw conveyor type feeder, and the second feeder is a screw conveyor feeder.
The dry supply device for waste according to any one of 1.