JP2013002723A - Slag melting apparatus and fluidized bed gasification melting facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a molten slag from being cooled by vapor generated when the molten slag discharged from a slag notch of a melting furnace is cooled in a water sealing tank and to prevent the slag notch from being occluded by the cooled slag.SOLUTION: A slag melting apparatus 23 includes a melting furnace 18 that melts and burns products generated in a fluidized bed gasification furnace 17 to generate the molten slag 2 and discharge the generated molten slag 2 from the slag notch 31, a slag discharge chute 19 which is mounted to the melting furnace 18 and connected to the slag notch 31, and a water sealing tank 21 which is disposed to water seal the side of an exit of the slag discharge chute 19 and which cools the molten slag 2. In the slag melting apparatus 23, there is provided a degassing device 22 that discharges a gas 34 from the slag discharge chute 19, the gas containing vapor corresponding to a volume of vapor generated by cooling the molten slag 2 in the water sealing tank 21.

Description

  In the present invention, solid combustibles such as municipal waste and industrial waste are gasified (partially combusted) in a fluidized bed gasifier, and the pyrolysis gas containing unburned char (unburned carbon) and ash is melted. The present invention relates to a slag melting device that is introduced into a furnace, melts ash at a high temperature by supplying air, and is separated into slag and combustion gas, and a fluidized bed gasification and melting facility including the same.

  Conventionally, in a fluidized bed gasification and melting facility, as shown in FIG. 4, the slag 2 fixed to the tap outlet 1 is heated by the slag burner 3 to be melted and removed, and the tap outlet 1 is blocked by the fixed slag. To prevent that.

  Further, in order to prevent low temperature gas 5 such as water vapor generated in a large amount in the water sealing tank 4 from flowing into the swirl melting furnace 6 through the tap outlet 1, the gas outlet 8 is provided in the slag discharge chute 7. So that most of the low-temperature gas 5 such as water vapor can be extracted from the gas extraction port 8 and discharged to such an extent that the combustion gas 9 in the swirling melting furnace 6 is not drawn (for example, , See Patent Document 1).

  The steam extraction apparatus 10 shown in FIG. 4 sucks the low-temperature gas 5 in the slag discharge chute 7 from the gas extraction port 8 and can return the sucked gas 5 to the swirl melting furnace 6. And a temperature measuring means 12 for measuring the temperature of the gas 5 withdrawn from the gas outlet 8, and connected to the temperature measuring means 12, and controlling the suction amount of the suction blower 11 based on the measured temperature, Extraction amount adjusting means for controlling the extraction amount so that most of the gas 5 such as low-temperature steam from the water sealing tank 4 is extracted from the gas extraction port 8 to such an extent that the combustion gas 9 is not drawn from the swirling melting furnace 6. 13.

JP 2001-147909 A

  However, in the conventional water vapor extraction apparatus 10 shown in FIG. 4, the temperature of the gas 5 extracted from the gas extraction port 8 is measured by the temperature measuring means 12, and the suction amount of the suction blower 11 is controlled based on the measured temperature. However, in the slag discharge chute 7, the gas 5 such as low-temperature steam generated in the water sealing tank 4 and the high-temperature combustion gas 9 from the swirling melting furnace 6 are unevenly distributed without being mixed sufficiently. If there is a gas 5 such as a large amount of low temperature steam in the slag discharge chute 7, for example, the high temperature combustion gas 9 is extracted from the gas extraction port 8 and the high temperature combustion gas is present. The suction amount of the suction blower 11 may be controlled to be small based on the temperature of 9. In such a case, the gas 5 such as low-temperature steam in the slag discharge chute 7 cannot be extracted from the gas extraction port 8 by an accurate amount.

  As a result, there is a possibility that the molten slag 2 is solidified by the gas 5 such as low-temperature steam in the slag discharge chute 7 and the outlet 1 is closed. In this case, in order to prevent the outlet 1 from being blocked by the cooled slag 2, the frequency of heating and removing the fixed slag 2 by the slag burner 3 is greatly increased. In this case, the cost of the fuel used in No. 3 is increased, and as a result, the running cost of the gasification and melting equipment is increased.

  In order to prevent such a situation from occurring, if a large amount of gas is extracted from the gas extraction port 8, the high-temperature combustion gas 9 is discharged from the swirling melting furnace 6 to the gas extraction port of the slag discharge chute 7. 8 may be extracted, and the thermal efficiency of this gasification and melting equipment will decrease.

  Further, when the combustion gas 9 in the melting furnace 6 is extracted from the gas extraction port 8 of the slag discharge chute 7, dust such as unmolten ash contained in the combustion gas 9 is removed from the gas extraction port 8 and the gas extraction port. These may adhere to the inner surface of the extraction pipe 14 connected to the mouth 8 and clog them. In order to process such dust, a dust processing apparatus is required, which leads to an increase in the size and cost of the gasification and melting equipment.

  The present invention has been made in order to solve the above-described problems, and this output is caused by water vapor generated when the molten slag discharged from the discharge port of the melting furnace is cooled in a water sealing tank. A slag melting device that can reliably prevent the molten slag discharged from the outlet and the outlet from being cooled and prevent the outlet from being blocked by the cooled slag, and a fluidized bed gasification provided with the same. It aims to provide melting equipment.

  A slag melting apparatus according to the present invention includes a melting furnace in which a product generated in a fluidized bed gasification furnace is melted and burned to generate molten slag, and the generated molten slag is discharged from an outlet. A slag melting device provided in the melting furnace and connected to the tap outlet, and a water sealing tank provided to seal the outlet side of the slag discharge chute and for cooling the molten slag In order to extract the gas containing water vapor corresponding to the volume of water vapor generated when the molten slag is cooled in the water-sealed tank from the slag discharge chute based on the cooled slag weight Means are provided.

  According to the slag melting apparatus according to the present invention, the product generated in the fluidized bed gasification furnace can be melted and combusted in the melting furnace, and the molten slag generated in the melting furnace is discharged from the outlet and the slag discharge chute. The water can be supplied to the water-sealed tank, cooled, and discharged from the melting apparatus.

  Then, when the molten slag is supplied to the water-sealed tank through the outlet and the slag discharge chute and cooled in the water-sealed tank, water vapor is generated, and the water vapor corresponding to the volume of the generated water vapor Can be extracted from the slag discharge chute by the degassing means based on the cooled slag weight. Thereby, it is possible to prevent the molten slag discharged from the tap outlet and the tap outlet from being cooled by water vapor generated when the molten slag is cooled in the water sealing tank, and the tap outlet is cooled. Can be prevented from being blocked by slag.

In the slag melting apparatus according to the present invention, a gas extraction volume by the degassing means may be 0.3 to 0.5 m ³ N / kg per unit slag weight.

The gas extraction volume of 0.3 to 0.5 m ³ N / kg per unit slag weight extracted by the degassing means is the sensible heat and latent heat of the slag, the water-sealed water evaporation transfer (contribution) ratio of slag, water The amount of generated air per unit slag weight derived based on the latent heat of vaporization and the volume per unit weight of water vapor.

And it can suppress that the high temperature combustion gas in a melting furnace is extracted through a slag discharge chute by making the extraction volume of gas into 0.5 m < ³ > N / kg or less per unit slag weight. . In addition, the gas extraction volume of 0.3 m ³ N / kg per unit slag weight is determined so that the molten slag discharged from the tap outlet and the tap outlet are cooled by steam and the tap outlet is blocked by the slag. This is the lower limit extraction volume so that it can be prevented.

  In the slag melting apparatus according to the present invention, the degassing means has a gas duct for extracting gas in the slag discharge chute and a watering part for applying water to the gas in the gas duct. Can do.

  If it does in this way, the gas containing the water vapor | steam which generate | occur | produces when molten slag is cooled with a water-sealed tank can be discharged | emitted from the inside of the slag discharge chute to the exterior of a gasification melting installation through a gas duct. And the watering part can separate (remove) the dust contained in this gas from the gas containing water vapor by applying water to the gas in this gas duct and dissolve it in water or mix it in water. It is possible to prevent dust from adhering to the inner surface of the gas duct on the downstream side of the water sprinkling portion and closing the gas duct.

  In the slag melting apparatus according to the present invention, after the water in the gas duct is sprinkled with water by the water sprinkling unit, the gas and the water can be passed through a granular material layer composed of a large number of granular materials.

  If it does in this way, the water sprayed from the water sprinkling part can be poured on the surface of many granular materials which comprise a granular material layer. As a result, when the gas containing vapor passes through the gaps between a large number of granular materials constituting the granular material layer, the chance that the dust contained in the gas contacts the water flowing on the surface of each granular material can be increased. . Therefore, dust contained in gas such as water vapor can be efficiently separated from the gas and removed.

  In the slag melting apparatus according to the present invention, the gas venting means can extract the gas in the slag discharge chute with a blower having a constant air flow rate characteristic.

  In this way, the gas corresponding to the volume of water vapor generated when the molten slag is cooled in the water-sealed tank can be accurately extracted from the slag discharge chute without being affected by pressure fluctuations in the slag discharge chute. Can do.

  In the slag melting apparatus according to the present invention, the degassing means may supply the gas extracted from the slag discharge chute into a secondary combustion chamber provided on the downstream side of the melting furnace.

  In this way, when the relatively low temperature gas extracted from the slag discharge chute is supplied to the secondary combustion chamber without being supplied to the melting furnace, the molten slag discharged from the outlet by this relatively low temperature gas. Is not cooled, and it is possible to prevent the outlet from being blocked by the cooled slag. Since the secondary combustion chamber has a lower pressure than the slag discharge chute, for example, the load on the blower for supplying the gas in the slag discharge chute to the secondary combustion chamber can be reduced, and the size is relatively small. It is possible to use a blower.

  In the slag melting apparatus according to the present invention, the degassing means has a gas extraction port portion for extracting gas from the slag discharge chute so that the opening of the gas extraction port portion faces the water sealing tank. It may be formed.

  If it does in this way, the water vapor | steam which generate | occur | produces and raises when molten slag is cooled with a water-sealed tank can flow easily into opening of this gas extraction port part. Therefore, the gas containing water vapor corresponding to the volume of the water vapor can be reliably extracted from the slag discharge chute by this degassing means. And it can prevent that the molten slag discharged | emitted and dropped from the tap outlet falls in the opening of a gas extraction opening | mouth part, and can prevent this opening being obstruct | occluded by slag.

  The fluidized bed gasification and melting equipment according to the present invention is characterized by including the slag melting device according to the present invention.

  The fluidized bed gasification and melting facility according to the present invention includes the slag melting device of the present invention, and this slag melting device operates in the same manner as described above.

  According to the slag melting apparatus and the fluidized bed gasification and melting facility according to the present invention, the gas containing the water vapor corresponding to the volume of water vapor generated when the molten slag is cooled in the water-sealed tank is slag by the degassing means. Since it is configured to be extracted from the discharge chute, the molten slag discharged from the outlet and the outlet can be reliably prevented from being cooled by the water vapor, and the outlet is closed by the cooled slag. Can be prevented. Accordingly, in order to prevent the tap outlet from being blocked by the cooled slag, it is possible to greatly reduce the frequency of melting and removing the slag adhered to the tap outlet by the slag burner. As a result, it is possible to reduce the cost of the fuel used in the slag burner, and consequently reduce the running cost of the gasification and melting equipment.

  Since the gas containing water vapor corresponding to the volume of water vapor generated when the molten slag is cooled in the water-sealed tank is extracted from the slag discharge chute, the high-temperature combustion gas in the melting furnace is slag Extraction from the slag discharge chute through the discharge chute can be suppressed, whereby the thermal efficiency of the gasification melting facility can be improved.

  Moreover, since it can suppress that the combustion gas in a melting furnace is extracted from this slag discharge chute through a slag discharge chute, dust, such as unmelted ash contained in the gas extracted from a slag discharge chute The amount of can be lowered. Therefore, the cost for processing the extracted dust can be reduced, and the gasification and melting equipment can be downsized.

It is a partial section front view showing fluidized bed type gasification fusion equipment concerning one embodiment of this invention. It is a partial expanded front view which shows the slag melting | fusing apparatus with which the fluidized bed type gasification melting equipment which concerns on the same embodiment is provided. It is a figure for demonstrating how to obtain | require the extraction amount of the gas containing the water vapor | steam discharged | emitted by the degassing apparatus with which the slag melting apparatus which concerns on the same embodiment is equipped. It is a fragmentary sectional front view which shows the water vapor extraction apparatus with which the conventional gasification melting equipment is provided.

  Hereinafter, an embodiment of a fluidized bed type gasification melting facility according to the present invention will be described with reference to FIGS. As shown in FIG. 1, the fluidized bed type gasification and melting facility 16 includes a fluidized bed type gasification furnace 17, a swirl melting furnace 18, a slag discharge chute 19, a slag burner 20, a water sealing tank 21, and a gas venting device 22. I have. The swirl melting furnace 18, the slag discharge chute 19, the slag burner 20, the water sealing tank 21, and the gas venting device 22 constitute a slag melting device 23.

  A fluidized bed gasification furnace 17 shown in FIG. 1 has a fluidized bed formed by combustion air supplied from an air supply port (not shown) at the bottom of the furnace, and a solid combustible (for example, This is an apparatus for partially combusting municipal waste, industrial waste, etc.) at a low air ratio and pyrolyzing solid combustibles in a fluidized bed maintained at a predetermined temperature (for example, 500 to 600 ° C.) by this combustion heat.

  As a result of partial combustion in the gasification furnace 17, incombustibles (substances mainly containing metals such as iron and aluminum) mixed in the solid combustibles are discharged from the lower discharge port provided at the furnace bottom by the discharge device 24. . The pyrolysis gas (CO, CH4, etc.), unburned char (unburned carbon), ash and combustion product gases (H2O, CO2, N2, etc.) generated in the gasification furnace 17 are provided on the top of the furnace. The gas is discharged from the discharge port 17 a and is introduced into the precombustion portion 26 of the swirl melting furnace 18 through the connection duct 25. The swirl melting furnace 18 includes a pre-combustion section 26, a substantially cylindrical inlet-side main combustion section 27, and an outlet-side main combustion section 28. Hereinafter, the pyrolysis gas, unburned char, ash, and combustion product gas introduced into the swirl melting furnace 18 are collectively referred to as unburned gas.

  In the pre-combustion unit 26, pyrolysis gas (CO, CH4, etc.) in the unburned gas, unburned char, and fuel supplied from the auxiliary burner 29 as necessary are supplied from an air supply port (not shown). Combustion is performed by the supplied combustion air and the temperature becomes high, and the ash melts at the outlet of the precombustion unit 26 to form slag. The unburned gas burned in the pre-combustion section 26 is introduced into the inlet main combustion section 27 together with the molten ash (slag). The slag 2 is separated from the combustion gas 9 at the inlet-side main combustion section 27.

  The temperatures in the inlet-side main combustion section 27 and the outlet-side main combustion section 28 are maintained at about 1300 to 1500 ° C. by burning the pyrolysis gas and the unburned char, so that the ash content in the unburned gas is melted. The slag state is maintained, and the slag is basically discharged from the outlet 31 at the bottom of the furnace. The molten slag 2 discharged from the swirl melting furnace 18 falls into the water sealing water 32 in the water sealing tank 21 and is rapidly cooled to become a granulated slag, which is taken out by a conveying means (not shown) such as a conveyor. The extracted granulated slag can be used effectively for roadbed materials.

  The unburned gas introduced into the swirl melting furnace 18 is burned in the pre-combustion section 26, the inlet-side main combustion section 27, and the outlet-side main combustion section 28, and then from the outlet-side main combustion section 28 to the secondary combustion chamber. It is sent to 33. In the secondary combustion chamber 33, the combustion air supplied from an air supply port (not shown) is set so that the total air ratio becomes 1.2 to 1.5, and is not contained in the combustion gas. The fuel is completely burned here. The sensible heat possessed by the exhaust gas discharged from the secondary combustion chamber 33 is effectively used as a heat source for a boiler (not shown).

  Next, with reference to FIG. 2, the tap port 31, the slag discharge chute 19, the slag burner 20, the water sealing tank 21, and the gas venting device 22 that constitute the slag melting device 23 will be described.

  The tap port 31 is for discharging the slag 2 from the swirl melting furnace 18, and as shown in FIG. 2, the bottom of the inlet side main combustion part 27 and the outlet side main combustion part 28 forming a substantially V-shape. Is provided at the intersection.

  The slag discharge chute 19 is arranged in a substantially vertical direction, and the upper end of the slag discharge chute 19 is provided to be coupled to the bottom of the swirl melting furnace 18 so as to surround the tap port 31 formed at the bottom of the swirl melting furnace 18. . And it arrange | positions so that the lower end part may be immersed in the water sealing water 32 with which the water sealing tank 21 is filled, and it is water-sealed.

  The slag burner 20 heats the slag 2 fixed to the tap hole 31 by the flame to be jetted, and melts and removes the fixed slag 2 to prevent the tap hole 31 from being blocked by the fixed slag. belongs to. The slag burner 20 is provided on the upper part of the slag discharge chute 19.

  The water-sealed tank 21 urges the molten slag 2 discharged from the tap 31 to drop into the water-seal water 32 so as to become a granulated slag, and transports the granulated slag to a conveyor or the like. It can be taken out by means (not shown). And the lower end part of the slag discharge chute | shoot 19 is water-sealed by arrange | positioning so that it may be immersed in the water seal water 32 with which the water seal tank 21 is filled.

  The degassing device 22 uses the slag discharge chute 19 to remove the gas 34 containing water vapor corresponding to the volume of water vapor generated when the molten slag 2 shown in FIG. 2 is cooled in the water-sealed tank 21 (water-sealed water 32). It is for extracting from.

  The degassing device 22 includes a gas duct 35 (first to third gas ducts 35a to 35c) shown in FIG. One end portion of the gas duct 35 is disposed through the peripheral wall portion of the slag discharge chute 19, and a gas outlet port portion 36 is formed at the one end portion. A gas 34 containing water vapor generated when the molten slag 2 is cooled in the water-sealed tank 21 can be sucked from the gas outlet 36.

  As shown in FIG. 2, the opening 36 a of the gas extraction port portion 36 is formed so as to face the water surface of the water sealing tank 21, and steam generated from the water surface is placed in the opening 36 a of the gas extraction port portion 36. Easy to flow in.

  The other end portion of the gas duct 35 is disposed so as to penetrate the lower peripheral wall portion of the secondary combustion chamber 33, and the gas 34 containing water vapor in the slag discharge chute 19 is sent into the secondary combustion chamber 33. Can be done.

  A dust removing unit 37 and a blower 38 are provided in the middle of the gas duct 35. The dust removing unit 37 removes dust such as unmelted ash contained in the gas 34 passing through the gas duct 35, and the dust adheres to the gas duct 35 and the gas duct 35 is clogged. This is to prevent failure. The blower 38 sucks the gas 34 containing water vapor in the slag discharge chute 19 and sends the sucked gas 34 into the secondary combustion chamber 33.

  The dust removing unit 37 includes a casing 39 in which a cavity is formed. As for this casing 39, the upper part of the cavity part is formed as the water sprinkling chamber 40, the granular material layer 41 is provided in the center part, and the water reservoir part 42 is formed in the lower part.

  In the side wall portion of the water sprinkling chamber 40, the rear end portion of the first gas duct 35 a having the gas extraction port portion 36 formed at the front end portion is disposed so as to penetrate the water vapor sucked from the gas extraction port portion 36. The contained gas 34 flows into the watering chamber 40. The upper end portion of the water spray chamber 40 is provided with a front end portion of the supply water pipe 43 penetrating therethrough, and a water sprinkling portion (shower portion) 44 is provided at the front end portion of the supply water pipe 43. The water sprinkling part 44 can wash away dust contained in the gas 34 flowing into the water sprinkling chamber 40 with water.

  And the rear-end part of this supply water pipe 43 is immersed in the water seal water 32 stored in the water seal tank 21, as shown in FIG. In addition, the supply water pipe 43 is provided with a circulation pump 45, and the circulation pump 45 sucks the water seal water 32 stored in the water seal tank 21, and the sucked water seal water 32 is contained in the water spray chamber 40. You can spray water.

  The granular material layer 41 is composed of a large number of granular materials arranged in contact with each other. After the water 34 is sprayed on the gas 34 in the watering chamber 40 by the watering portion 44, the gas 34 and the water are It is made to pass through a granular material layer 41 composed of a large number of granular materials, and can be fed into a water reservoir 42 formed below the granular material layer 41. The many granular materials are, for example, sand.

  As shown in FIG. 2, the water reservoir portion 42 is a place where water sprinkled from the water sprinkling portion 44 accumulates, and the water accumulated in the water reservoir portion 42 passes through the return water pipe 46 and enters the water sealing tank 21. Returned. In this way, the water seal water 32 in the water seal tank 21 pumped up by the circulation pump 45 is sprinkled into the water spray chamber 40 and passes through the granular material layer 41 and the water reservoir 42 to return to the original water seal tank. 21 is returned. In this way, the water seal water 32 can be circulated and used.

  Further, the gas 34 containing water vapor sent into the water reservoir 42 is sucked into the blower 38 through the second gas duct 35b, and then sent into the secondary combustion chamber 33 through the third gas duct 35c. This blower 38 is, for example, a roots blower. Of course, a blower other than the Roots blower may be used.

  Furthermore, the first and third gas ducts 35a and 35c, the supply water pipe 43, and the return water pipe 46 shown in FIG. 2 are provided with valves 47, 48, 49, and 50, respectively.

  Next, the extraction air volume of the blower 38 shown in FIG. 2 will be described. The blower 38 is a gas containing water vapor corresponding to the volume of water vapor generated when the molten slag 2 generated in the swirl melting furnace 18 falls into the water sealing tank 21 and is cooled in the water sealing tank 21. The extraction air volume is set so that 34 can be extracted from the slag discharge chute 19, and has constant air volume characteristics. The blower 38 is rotationally driven by an electric motor (not shown) so as to rotate at a predetermined constant speed.

  Here, the fluidized bed type gasification and melting equipment 16 gasifies (partially combusts) solid combustibles such as municipal waste and industrial waste having a substantially constant weight per day in the gasification furnace 17, and unburned char (unburned) The pyrolysis gas containing fuel carbon), ash, and combustion product gas is introduced into the swirl melting furnace 18, and the ash is melted at a high temperature by supplying air. It is set to be generated in the furnace 18. Therefore, water vapor generated when the molten slag 2 is cooled in the water-sealed tank 21 is also generated at a substantially constant volume per hour.

  Therefore, an electric motor is set to drive the blower 38 at a constant rotational speed so that the gas 34 containing water vapor generated by the blower 38 at a substantially constant volume per hour can be extracted from the slag discharge chute 19. Yes.

  For example, when the fluidized bed gasification and melting facility 16 is initially installed, the weight of the solid combustible material per day processed by the fluidized bed gasification and melting facility 16 (the weight of the molten slag 2 generated every hour) is determined. Then, since the volume of water vapor generated every hour is also determined, the rotation speed of the electric motor is set so that this water vapor can be extracted accurately.

  In addition, when the weight of the solid combustible material processed per day by the fluidized bed gasification melting equipment 16 (the weight of the molten slag 2 generated every hour) is changed, it is generated in the slag discharge chute 19 accordingly. The setting of the rotation speed of the electric motor is changed so that the water vapor to be extracted can be accurately extracted.

Next, the extraction volume of the gas 34 containing water vapor extracted from the slag discharge chute 19 by the blower 38 shown in FIG. 2 will be described. The extraction volume of the gas 34 containing water vapor is an amount obtained by multiplying the slag weight by 0.3 to 0.5 m ³ N / kg, that is, 0.3 to 0.5 m ³ N / kg per unit slag weight. The rotational speed of the blower 38 is set so that

  The extraction volume of the gas 34 per unit slag weight is the sum A of the sensible heat and latent heat of the slag 2 shown in FIG. 3, the water seal water evaporation transfer (contribution) ratio D of the slag 2, the latent heat E of water evaporation, and This is a volume calculated based on the volume per unit weight of water vapor.

Then, by setting the extraction volume of the gas 34 per unit time to 0.5 m ³ N / kg or less per unit slag weight, the high-temperature combustion gas 9 in the swirl melting furnace 18 is extracted through the slag discharge chute 19. Can be suppressed.

Moreover, the extraction volume of the gas 34 of 0.3 m ³ N / kg per unit slag weight is such that the molten slag 2 and the outlet 31 discharged from the outlet 31 are cooled by steam, and the outlet 31 is slag. This is the lower limit extraction volume for preventing the blockage by 2.

  FIG. 3 is a diagram for explaining how to obtain the extraction amount (volume and weight) per unit time of the gas 34 containing water vapor, and slag sensible heat and latent heat used to obtain the extraction amount of the gas 34. An added value (A) of slag, an amount of slag (B to C) (kg) generated per 1 ton of garbage, and the like are shown.

As can be seen from FIG. 3, when the waste processing amount is 120 (N) t / day, the required extraction amount of the gas 34 is 102 (P) to 230 (Q) m ³ N / h. However, in consideration of variations such as the amount of dust treatment, it is preferable to set the required extraction amount of the gas 34 to 100 to 300 m ³ N / h.

  In this example, the total A of the slag sensible heat and latent heat shown in FIG. 3 is 500, the slag amounts B to C are 20 to 50, the water-sealed water evaporation transition ratio D is 0.5, and the latent heat E of water evaporation is , 600. Then, the evaporation amount F from the slag water seal water is 0.42, G to H is 8.33 to 20.8, I is 0.52, and J to K is 10.4 to 25.9. Become. Further, the air volumes L to M of the slag burner 20 are 50 to 100, the waste disposal amount N is 120, and the required extraction amounts P to Q are 102 to 230.

  Here, the slag burner cooling air volumes L to M are the air volumes of air that is constantly discharged from the slag burner 20 in order to cool the slag burner 20 in order to prevent the slag burner 20 from being seized or clogged. This air volume is set to an appropriate air volume.

  Next, the operation of the slag melting device 23 including the swivel melting furnace 18, the slag discharge chute 19, the slag burner 20, the water sealing tank 21, and the gas venting device 22 configured as described above will be described.

  According to the slag melting apparatus 23 shown in FIG. 2, the product (unburned gas and ash content therein) generated in the fluidized bed gasification furnace 17 can be melted and combusted in the swirl melting furnace 18, and this swirl melting is performed. The molten slag 2 generated in the furnace 18 can be supplied to the water-sealed tank 21 through the outlet 31 and the slag discharge chute 19, cooled, and discharged from the swirl melting furnace 18. Moreover, by heating and removing the slag 2 fixed to the tap hole 31 with the slag burner 20, it is possible to prevent the tap port 31 from being blocked by the fixed slag.

  Then, when the molten slag 2 falls through the tap 31 and the slag discharge chute 19 to the water sealing tank 21 and is cooled in the water sealing tank 21, water vapor is generated, and the volume of the generated water vapor The gas 34 containing the water vapor corresponding to the above can be extracted from the slag discharge chute 19 by the degassing device 22. Thereby, the molten slag 2 discharged from the tap outlet 31 and the tap outlet 31 are prevented from being cooled by water vapor generated when the molten slag 2 is cooled in the water-sealed tank 21 (water-sealed water). As a result, the outlet 31 can be prevented from being blocked by the cooled slag 2.

  Thus, in order to prevent the tap port 31 from being blocked by the cooled slag 2, the frequency of heating and removing the slag 2 fixed to the tap port 31 by the slag burner 20 can be greatly reduced. Is possible. As a result, it is possible to reduce the cost of fuel and the like used in the slag burner 20, and consequently reduce the running cost of the gasification melting facility 16.

  And since it was set as the structure which extracts the said gas 34 containing the said water vapor | steam equivalent to the volume of the water vapor | steam generated when the molten slag 2 is cooled with the water-sealed tank 21, from the slag discharge chute 19, it is the high temperature in the swirling melting furnace 18. The combustion gas 9 can be prevented from being extracted from the slag discharge chute 19 through the slag discharge chute 19, thereby improving the thermal efficiency of the gasification and melting equipment 16.

  Further, since the combustion gas 9 in the swirl melting furnace 18 can be suppressed from being extracted from the slag discharge chute 19 through the slag discharge chute 19, it is included in the gas 34 extracted from the slag discharge chute 19. The amount of dust such as unmelted ash can be reduced to a low level. Therefore, the cost for processing the extracted dust can be reduced, and the gasification and melting equipment 16 can be downsized.

  Further, according to the gas venting device 22 shown in FIG. 2, a gas 34 containing water vapor generated when the molten slag 2 is cooled in the water sealing tank 21 is passed through the gas duct 35 from the slag discharge chute 19 to It can be fed into the next combustion chamber 33. Then, the water sprinkling part 44 separates (removes) the dust from the gas 34 containing water vapor by applying water to the dust contained in the gas 34 flowing into the water sprinkling chamber 40 of the dust removing part 37 to form water. It can be dissolved or mixed in water, and dust can be prevented from adhering to the inner surfaces of the second and third gas ducts 35b and 35c on the downstream side of the dust removing portion 37 and closing the gas duct.

  Moreover, since the water sprinkling part 44 is spraying water on the dust contained in the gas 34 flowing into the water sprinkling chamber 40, the temperature of the gas 34 can be lowered. Can be prevented.

  Furthermore, as shown in FIG. 2, the water sprinkled from the water sprinkling part 44 can be made to flow on the surfaces of a large number of granular materials constituting the granular material layer 41. As a result, when the gas 34 containing steam passes through the gaps between the large number of granular materials constituting the granular material layer 41, the chance that the dust contained in the gas 34 contacts the water flowing on the surface of each granular material is increased. be able to. Therefore, dust contained in the gas 34 such as water vapor can be efficiently separated from the gas 34 and removed.

  Further, as described above, the water-sealed tank 21 is a crushed slag in which the molten slag 2 discharged from the outlet 31 of the swirling melting furnace 18 and falling is urged with water to become a granulated slag. The granulated slag can be taken out by a conveying means such as a conveyor. And the dust contained in the water which flows into this water sealing tank 21 from the water reservoir 42 can also be taken out by this conveying means.

  2 is used as the blower 38 shown in FIG. 2, and the gas 34 corresponding to the volume of water vapor generated when the molten slag 2 is cooled in the water-sealed tank 21 is discharged from the slag. Without being affected by pressure fluctuations in the chute 19 and the secondary combustion chamber 33, it can be accurately extracted from the slag discharge chute 19 and fed into the secondary combustion chamber 33.

  In addition, the relatively low temperature gas 34 extracted from the slag discharge chute 19 is supplied to the secondary combustion chamber 33 without being supplied to the melting furnace 18, so that the relatively low temperature gas 34 swirls and melts. It is possible to prevent the inside of the furnace 18 from being cooled. Since the secondary combustion chamber 33 has a lower pressure than the slag discharge chute 19, the load on the blower 38 for supplying the gas 34 in the slag discharge chute 19 into the secondary combustion chamber 33 is reduced. It is possible to use a relatively small blower 38.

  The secondary combustion chamber 33 has a lower pressure than the swirl melting furnace 18 and the slag discharge chute 19 because a suction ventilator (not shown) is provided on the downstream side of the secondary combustion chamber 33. Due to the suction force of the suction ventilator, the swirl melting furnace 18, the slag discharge chute 19, and the secondary combustion chamber 33 have negative pressure, and the secondary combustion chamber 33 is more than the swirl melting furnace 18 and the slag discharge chute 19. This is because it is arranged on the downstream side.

  Furthermore, as shown in FIG. 2, the opening 36 a of the gas outlet port 36 for extracting the gas 34 from the slag discharge chute 19 is formed so as to face the water surface of the water sealing tank 21, so that the molten slag 2 is The water vapor generated and raised when cooled in the water sealing tank 21 can easily flow into the opening 36 a of the gas extraction port 36. Therefore, the gas 34 containing water vapor corresponding to the volume of the water vapor can be reliably extracted from the slag discharge chute 19 by the degassing device 22. Then, it is possible to prevent the molten slag 2 discharged and dropped from the tap outlet 31 from falling into the opening 36a of the gas outlet port 36, and thus preventing the opening 36a from being blocked by the slag 2. it can.

  However, in the above embodiment, as shown in FIG. 2, the distal end portion of the gas extraction port portion 36 is bent by about 90 ° so that the opening 36 a faces the water surface of the water seal tank 21, Although the generated steam is easy to flow into the opening 36a of the gas outlet 36, other configurations may be adopted. For example, the front end of the gas outlet port 36 arranged horizontally may be formed into a shape that is cut obliquely, and the opening edge may be formed to go obliquely downward.

  In the above embodiment, as shown in FIG. 2, one gas outlet port 36 is provided at one end of the gas duct 35. Instead, a plurality of gas outlets are provided at one end of the gas duct 35. It is good also as a structure which provided the opening part 36 and provided these several gas extraction opening parts 36 in the perimeter of the surrounding wall part of the slag discharge chute 19 for every fixed angle.

  By configuring in this way, the steam generated from the water surface of the water-sealed tank 21 can surely flow into the openings 36 a of the plurality of gas outlet ports 36.

  In the above embodiment, the combustion gas 9 swirls at the inlet-side main combustion portion 27 and the outlet-side main combustion portion 28 and does not swirl at the pre-combustion portion 26. It is good also as a structure swirled by the precombustion part 26, the entrance side main combustion part 27, and the exit side main combustion part 28. FIG. Moreover, it is good also as a structure which the combustion gas 9 swirls in the precombustion part 26, and does not swirl in the entrance side main combustion part 27 and the exit side main combustion part 28.

  As described above, the slag melting apparatus according to the present invention and the fluidized bed gasification and melting equipment provided with the slag melting steam generated when the molten slag discharged from the outlet of the melting furnace is cooled in the water-sealed tank. By reliably suppressing that the molten slag discharged from the tap outlet and the tap outlet are cooled, it has an excellent effect of preventing the tap outlet from being blocked by the cooled slag, It is suitable for application to such a slag melting apparatus and a fluidized bed type gasification melting facility equipped with the same.

2 Molten slag 9 Combustion gas 16 Fluidized bed type gasification melting equipment 17 Fluidized bed type gasification furnace 17a Upper discharge port 18 Swivel melting furnace 19 Slag discharge chute 20 Slag burner 21 Water sealing tank 22 Degassing device 23 Slag melting device 24 Discharge device 25 Connection duct 26 Pre-combustion part 27 Inlet side main combustion part 28 Outlet side main combustion part 29 Auxiliary burner 30 Arrow 31 Outlet 32 Water-sealed water 33 Secondary combustion chamber 34 Gas containing steam 35 Gas duct 35a First gas duct 35b First 2 Gas duct 35c 3rd gas duct 36 Gas extraction port part 36a Opening 37 Dust removal part 38 Blower 39 Casing 40 Sprinkling chamber 41 Granule layer 42 Reservoir part 43 Supply water pipe 44 Sprinkling part 45 Circulation pump 46 Return water pipes 47, 48, 49, 50 valves

Claims (8)

The product produced in the fluidized bed gasification furnace is melted and combusted to produce molten slag, and the produced molten slag is discharged from the outlet. In a slag melting apparatus comprising a slag discharge chute connected to a shed and a water sealing tank for cooling the molten slag provided to seal the outlet side of the slag discharge chute,
Degassing means for extracting the gas containing water vapor corresponding to the volume of water vapor generated when the molten slag is cooled in the water sealing tank from the slag discharge chute based on the cooled slag weight. A slag melting apparatus comprising: 2. The slag melting apparatus according to claim 1, wherein a gas extraction volume by the degassing unit is 0.3 to 0.5 m ³ N / kg per unit slag weight.   3. The slag according to claim 1, wherein the degassing unit includes a gas duct for extracting gas in the slag discharge chute and a watering part for spraying water on the gas in the gas duct. Melting equipment.   4. The slag melting apparatus according to claim 3, wherein water is poured into the gas in the gas duct by the water sprinkling unit, and then the gas and the water are passed through a granular material layer composed of a large number of granular materials.   The slag melting apparatus according to any one of claims 1 to 4, wherein the degassing means extracts the gas in the slag discharge chute with a blower having a constant air flow rate characteristic.   The said degassing means supplies the gas extracted from the said slag discharge chute into the secondary combustion chamber provided in the downstream of the said melting furnace. Slag melting device.   The degassing unit has a gas extraction port for extracting gas from the slag discharge chute, and an opening of the gas extraction port is formed to face the water sealing tank. The slag melting apparatus according to any one of claims 1 to 6.   A fluidized-bed gasification and melting facility comprising the slag melting device according to any one of claims 1 to 7.

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