JP2011206696A - Deposit drying device using waste heat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deposit drying device using waste heat capable of reducing a cost for drying a deposit.SOLUTION: A gasifying and melting system 200 includes a gasifying and melting furnace 300, an exhaust gas treatment device 14 for discharging dust 15, a neutralizing column 16 for discharging a deposit 20, and a mist Cottrell precipitator 17, etc. A deposit drying device 100 installed alongside the gasifying and melting system 200 includes a floor 30 and an upper space 32 for housing the deposit 20, a mixing plow 40 for plowing up the deposit 20, and a lower space 31 formed under the floor 30, etc. Into the upper space 32, heated air Awhich is obtained by cooling air A that has been used for cooling the gasifying and melting furnace 300 is introduced. Meanwhile, hot water 23 via heat exchange in a second heat exchanger 12 is allowed to pass through a road heating part 36 in the lower space 31 and thus the deposit 20 housed in the upper space 32 is dried while plowed up by the mixing plow 40.

Description

  The present invention relates to a starch drying apparatus for drying starch containing moisture discharged from gasification melting equipment, wastewater treatment equipment, etc., and in particular, circulating water and melting for cooling a water cooling jacket of a gasification melting furnace. The present invention relates to a starch drying apparatus using waste heat for drying starch containing moisture by using retained heat of heated air that has passed through a heat exchanger for recovering waste heat from exhaust gas at the furnace outlet.

  Metals are recycled in scrap cars and home appliances. Specifically, valuable metals are recovered after being crushed with an industrial shredder. Fragments of plastic, rubber, glass, and the like left after the recovery of valuable metals are called shredder dust, and are conventionally sent to landfill. However, in recent years, it has become obligatory to carry out recycling in accordance with the revision of the Waste Management Law, the enactment and enforcement of the Home Appliance Recycling Law and the Automobile Recycling Law. For this reason, the gasification and melting treatment method is attracting attention as a shredder dust treatment facility.

  A typical treatment process of this gasification and melting method is to put a waste in a low-oxygen atmosphere furnace and thermally decompose it at a temperature of 500 to 550 ° C. to produce pyrolysis gas, unburned carbon and pyrolysis residue. The gas and unburned carbon are introduced into a combustion / melting process, and are burned at a high temperature of 1200 ° C. or higher to bring the ash to melting / slagging. Good quality iron and aluminum that are not oxidized can be recovered from the pyrolysis residue. In addition, it is excellent in the decomposition of dioxins in order to stably burn gas with good combustion characteristics at high temperature, and furthermore, the amount of exhaust gas can be reduced by combustion with reduced excess air ratio, so that the amount of NOx generated can be reduced and the exhaust gas treatment device There is an advantage that can be reduced in size.

  The gasification melting method is roughly classified into a shaft furnace type in which pyrolysis and melting are performed in one furnace, and a method in which pyrolysis and melting are performed in different furnaces. Further, the former (shaft furnace type) is classified into a coke bed type, an oxygen type, a plasma type, etc., and the latter is classified according to the type of furnace used for pyrolysis, and a kiln type using a kiln furnace and a fluidized bed furnace are used. There are two main types: fluidized bed.

  The gasification and melting equipment by the kiln method and the fluidized bed method mainly comprises a gasification and melting furnace and an exhaust gas treatment equipment, and the gasification and melting furnace is a melting gas disposed in the gasification furnace and the subsequent stage. A valuable metal is recovered from the gasification furnace and slag is discharged from the melting furnace. In the exhaust gas treatment facility, the starch leached from fly ash collected by the bag filter for treating the exhaust gas generated in the gasification melting furnace and the exhaust gas treated by the exhaust gas treatment facility are further cooled and washed. The neutralized starch discharged from the drained water is discharged. In general, the water-leached starch and neutralized starch are often landfilled. However, depending on the operator, the starch may be transferred to a gasifier after being dried in a drying kiln facility. Moreover, since it contains Cu slightly, a recycling process is performed as Cu raw material.

  In addition, as a gasification melting apparatus provided with the gasification furnace and the gasification furnace, there exists a thing shown in patent document 1, for example. In this gasification and melting apparatus, a gasification furnace and a melting furnace are connected by a communication duct, a gas injection nozzle is provided in the communication duct, and a duct deposited on the communication duct by injecting a cleaning gas from the gas injection nozzle. By removing the dust, the dust accumulated in the communication duct is prevented from closing the communication duct and reducing the exhaust gas suction ability of the gasification furnace.

JP 2008-207179 A

  However, in the conventional gasification and melting equipment described above, the starch obtained by leaching the fly ash collected by the bag filter constituting the exhaust gas treatment equipment and the exhaust gas treated by the exhaust gas treatment equipment are further cooled and washed. Then, the neutralized starch discharged from the waste water was dried by a drying kiln facility. Therefore, there was a problem that the consumption cost of the recycled heavy oil used as a heat source of the drying kiln facility was increased.

  Therefore, the present invention has been made in view of such problems, and does not use recycled heavy oil as a heat source of a dry kiln, and can reduce the cost of starch drying treatment by using another heat source that does not cost. An object of the present invention is to provide a starch drying apparatus utilizing possible waste heat.

  In order to solve the above-mentioned problem, the invention described in claim 1 is formed by having an upper space serving as a storage space for storing a material to be dried and a lower space partitioned by a floor on the lower side of the upper space. The industrial waste is gasified by forming a fluidized bed while blowing air from the lower part of the gasification furnace and thermally decomposing it, and recovering ferrous and non-ferrous metals contained in the industrial waste. In addition, a heat medium that is heat-exchanged by a cooling device is disposed in the lower space in order to cool the melting furnace of the gasification melting furnace that introduces pyrolysis gas into the melting furnace communicated with the gasification furnace to generate slag. Introducing into the upper space by introducing into the upper space the heated air that has been introduced into the generated load heating and heat-exchanged by the first heat exchanger for recovering waste heat from the exhaust gas passing through the melting furnace. The contained material to be dried characterized by drying.

  In order to solve the above-mentioned problem, the present invention described in claim 2 is a starch drying apparatus using waste heat according to claim 1, wherein the cooling device has a water cooling jacket structure for cooling the melting furnace with circulating water. The heating medium is water, and by cooling the melting furnace, the heated water is heated in the lower space after being heat-exchanged for further cooling by the second heat exchanger. It is characterized by being introduced into the road heating.

  In order to solve the above-mentioned problem, the present invention described in claim 3 is a starch drying apparatus using waste heat according to claim 1 or 2, for stirring the material to be dried accommodated in the upper space. A stirrer is further provided.

  In order to solve the above-mentioned problem, the present invention described in claim 4 is a starch drying apparatus using waste heat according to any one of claims 1 to 3, wherein the material to be dried is a gasification melting furnace. Waste water after leaching the fly ash collected by the bag filter that constitutes the exhaust gas treatment facility for treating the exhaust gas and / or exhaust gas after further cooling and washing the exhaust gas treated by the exhaust gas treatment facility of the gasification melting furnace It is characterized by being neutralized starch discharged from.

  According to the starch drying apparatus using waste heat according to the present invention, it is not necessary to use recycled heavy oil by using waste heat in the gasification melting furnace, thereby reducing the cost of starch drying treatment. There is an effect that can be.

1 is a configuration diagram illustrating a preferred embodiment of a starch drying apparatus using waste heat according to the present invention and a gasification melting system to which the starch drying apparatus is applied. It is a perspective view which shows a starch drying apparatus. It is a top view which shows the detail in the lower space shown in FIG.

[Configuration of gasification and melting system]
Hereinafter, a starch drying apparatus using waste heat according to the present invention will be described in detail based on a preferred embodiment. FIG. 1 is a configuration diagram showing a starch drying apparatus according to an embodiment of the present invention and a gasification melting system to which the starch drying apparatus is applied. In addition, in FIG. 1, illustration of the gasification furnace, the melting furnace, the heat exchanger provided in the latter stage, etc. is shown in cross section.

  First, a gasification melting system to which the starch drying apparatus according to the present invention is applied will be described. As shown in FIG. 1, the gasification and melting system 200 generally includes a pulverization facility 1 for pulverizing industrial waste such as ASR (automobile-derived shredder dust), and a shredder dust introduced from the pulverization facility 1 onto a fluidized bed. Gasification furnace 2 that thermally decomposes and gasifies, a sorter 3 that separates the incombustible material discharged from the gasification furnace 2 from a fluid medium (for example, sand), and an incombustible material that is sorted by the sorter 3 Is arranged so as to communicate with the gasification furnace 2 and the magnetic separator 4 for sorting the non-ferrous metals 5a and the iron scrap 5b, and is burned while supplying air to the pyrolysis gas generated in the gasification furnace 2, A melting furnace 6 that discharges as slag 7 by oxidizing and melting a metal such as Al transferred together with the pyrolysis gas, a water-cooling jacket 8 that cools the refractory in the melting furnace 6, and a water-cooling jacket 8 through a pipe 11. In A pump 9 that circulates reject water, a tank 10 that stores cooling water supplied to the pump 9, a first heat exchanger 12 provided in the middle of the pipe 11, and an outlet side of the melting furnace 6 A second heat exchanger 13 that recovers waste heat from the melting furnace outlet exhaust gas, an exhaust gas treatment facility 14 that processes the exhaust gas from the second heat exchanger 13 and discharges dust 15, and an exhaust gas from the exhaust gas treatment facility 14 A neutralization tower 16 that is provided on the side and neutralizes the inflowing exhaust gas, a mistcottel 17 that removes dust remaining in the exhaust gas at the outlet of the neutralization tower 16, an exhaust fan 18 that sucks gas in the mistcotrel 17, A chimney 19 for releasing the gas from the exhaust fan 18 to the atmosphere, a thickener 21 for generating the starch 20 generated by treating the waste water from the neutralization tower 16 and the mist cot rel 17 in a waste water treatment facility, and high-temperature exhaust gas In order to cool the melting furnace 6 heated by the second heat exchanger 13, a fan 22 for supplying air to the second heat exchanger 13 for heat exchange is provided. The starch 20 is a starch obtained by leaching fly ash collected by a gasification melting furnace exhaust gas treatment bag filter, a neutralized starch recovered by the thickener 21, or the like. Further, the gasification furnace 2 and the melting furnace 6 form a so-called gasification melting furnace 300.

[Configuration of starch drying equipment]
The starch drying apparatus 100 is introduced into the first heat exchanger 12 and warm water 23 (about 50 ° C.) as a heat medium heated by heat exchange with circulating water flowing through the pipe 11 and the second heat exchange. The starch 20 is dried while being stirred by the stirring device 40 based on the heated air A (about 200 ° C.) from the fan 22 heat-exchanged by the vessel 13. FIG. 2 shows a perspective view of the starch drying apparatus 100. This starch drying apparatus 100 is roughly composed of a floor 30 into which undried starch 20 is carried, and a lower space 31 (under the lower part) ( 1), an upper space 32 formed in the upper part of the floor 30 as a storage space for storing the starch 20 to be dried, and a cover member (ceiling member) made of a heat-resistant vinyl sheet or the like forming the upper space 32 33, an entrance / exit 37 for taking the starch 20 in and out of the starch drying apparatus 100, and an agitation device for stirring the undried starch 20 provided on the floor 30 and carried onto the floor 30 during the drying process 40. Here, a building is constituted by the structure 38, the floor 30, the cover member 33, and the doorway 37 forming the lower space 31.

The second heat exchanger 13 is installed for the purpose of recovering waste heat from the exhaust gas at the melting furnace outlet, and the heat exchanged heat air (20 ° C. → 200 ° C.) is introduced into the melting furnace as combustion air. However, some of them are introduced into the upper space 32 through the pipe 34 as heated air A. The air A _L introduced into the upper space 32 is discharged to the atmosphere after being dust by bag filter (not shown) from the pipe 35 after the action (see FIG. 1) in order to dry the sediment was 20.

  FIG. 3 shows details in the lower space 31. As shown in the drawing, in the lower space 31, an end of a pipe 24 for introducing the hot water 23 supplied from the first heat exchanging device 12 is guided and arranged at the end of the pipe 24. Is connected to a load heating section 36 formed by meandering pipe materials. The warm water 23 is introduced into the load heating unit 36 to heat the floor 30, thereby drying the starch 20 from below.

  As shown in FIG. 2, the stirring device 40 includes guide rails 42 provided on both sides of the floor 30, a movable part 41 that reciprocates using a motor as a drive source while being guided by the guide rails 42, and a movable part 41, provided at regular intervals, and provided with a plurality of whiskers 43 for stirring the starch 20 on the floor 30.

[Operation of starch drying equipment and gasification high temperature melting system]
Next, the starch drying apparatus 100 described above will be described in detail including the operation of the gasification melting system 200. First, shredder dust pulverized by the pulverization facility 1 is put into the gasification furnace 2. In the gasification furnace 2, the high-temperature fluidized medium is flowing by the flow-in air, and the shredder dust thrown in by this is pyrolyzed to form pyrolysis gas, and the incombustible material is taken out from the furnace bottom and sorted. It is separated from the fluid medium by machine 3. The separated incombustible material is separated into non-ferrous metals 5a and iron scrap 5b by the magnetic separator 4.

  The pyrolysis gas pyrolyzed in the gasification furnace 2 is further sent to the melting furnace 6. In the melting furnace 6, the dust-containing gas is melted at a high temperature using the combustion heat of the pyrolysis gas generated in the gasification furnace 2 to generate the slag 7. Further, the exhaust gas from the melting furnace 6 is cooled by air exchange by the air supplied by the fan 22 in the second heat exchanger 13 and cooled by spraying the cooling water 25, and then the exhaust gas. It is sent to the processing facility 14. In the exhaust gas treatment facility 14, the exhaust gas sent from the second heat exchanger 13 is treated and the dust 15 is discharged. The exhaust gas discharged from the exhaust gas treatment facility 14 is neutralized in the neutralization tower 16, and then dust remaining in the exhaust gas at the outlet of the neutralization tower 16 is removed by the mist cotrel 17. Further, the exhaust gas from the mist cot rel 17 is sent to the chimney 19 by the exhaust fan 18 and discharged from the chimney 19 into the atmosphere.

The drainage discharged from the neutralization tower 16 and the mist cot rel 17 precipitates impurities contained in the drainage by the thickener 21 of the wastewater treatment plant to produce a starch 20. It is to be noted that moisture is also removed from the solidified starch 20 by a filter press or the like. A predetermined amount of the starch 20 is carried into the upper space 32 of the starch drying device 100. The starch 20 accommodated in the upper space 32 of the starch drying apparatus 100 is agitated by the reciprocating movement of the movable portion 41 of the agitating apparatus 40, and thereby waste heat for drying (described later) ( Warm water 23 and air A _L ) can be evenly distributed over the starch 20.

  As described above, there are two types of starch 20: starch obtained by leaching fly ash from a gasification melting furnace and neutralized starch accompanying wastewater treatment. These are simultaneously supplied to the starch drying apparatus 100. It is not carried in, but carried in alternately. The drying time of the water-leached starch is, for example, 10 hours, the take-in / loading operation is, for example, 2 hours, the drying time of the neutralized starch is, for example, 12 hours, and the combined drying time per day is 22 hours.

In the upper space 32 of the starch drying apparatus 100, air A _L (heated air), which is adjusted to a temperature of, for example, 60 ° C. by mixing heated air A of about 200 ° C. with piping 34 through the pipe 34, is on the floor 30. Into the upper space 32, the starch 20 is dried from above. Here, the reason why the temperature of the heated air A is lowered and then introduced is that if the heated air A at about 200 ° C. is introduced as it is, there is a risk of causing a fire. Further, the starch 20 is also dried in the lower space 31 from below by hot water (heat medium) 23 having a temperature of about 50 ° C. introduced from the first heat exchanger 12 through the pipe 24. In addition, by stirring the starch 20 with the stirring device 40, the drying time can be greatly shortened compared to natural drying by turning the interior that is difficult to dry upside down. Thereby, the regenerated heavy oil conventionally required for the dry kiln facility can be eliminated. In addition, the temperature of the air discharged | emitted from the piping 35 falls to about 20 degreeC, and the temperature of the warm water discharged | emitted through the lower space 31 has fallen to about 30 degreeC.

[Effect of the embodiment]
According to the starch drying apparatus according to the present embodiment, the hot water heat-exchanged by the first heat exchanger 12 with the circulating water of the water-cooling jacket 8 that is a cooling device provided in the melting furnace 6 is starch-dried. By introducing the waste heat heat-exchanged by the second heat exchanger 13 into the upper space 32 and drying the starch 20 while introducing it into the load heating section 36 of the lower space 31 of the apparatus 100, There is an effect that the cost of the drying treatment of the Japanese starch can be greatly reduced.

  As mentioned above, although preferable embodiment was described, the starch drying apparatus which concerns on this invention is not restricted to the installation of the system using a fluidized bed type gasification melting furnace, Exhaust gas and waste_water | drain from normal temperature or more are discharged | emitted from a furnace body. The present invention can be applied to the entire gasification melting furnace.

  The present invention adds a starch drying facility to a facility that discharges waste heat above a predetermined temperature and discharges a material to be dried that requires a drying treatment such as starch. The present invention can also be applied to drying objects other than products.

DESCRIPTION OF SYMBOLS 1 Crushing equipment 2 Gasifier 3 Sorter 4 Magnetic separator 5a Non-ferrous metal 5b Iron scrap 6 Melting furnace 7 Slag 8 Water cooling jacket 9 Pump 10 Tank 11 Pipe 12 First heat exchanger 13 Second heat exchanger 14 Exhaust gas Treatment facility 15 Dust 16 Neutralization tower 17 Mist cotrel 18 Exhaust fan 19 Chimney 20 Starch 21 Thickener 22 Fan 23 Hot water 24 Pipe 25 Cooling water 30 Floor 31 Lower space 32 Upper space 33 Cover member 34 Pipe 35 Pipe 36 Load heating section 37 Entrance / Exit 38 Structure 40 Stirrer 41 Movable Part 42 Guide Rail 43 Fired 100 Starch Dryer 200 Gasification Melting System 300 Gasification Melting Furnace

Claims (4)

An upper space serving as a storage space for storing an object to be dried, and a sealable building formed with a lower space partitioned by a floor on the lower side of the upper space;
Industrial waste is gasified by forming a fluidized bed while blowing air from the bottom of the gasification furnace and thermally decomposing it, recovering iron and non-ferrous metals contained in the industrial waste, and communicating with the gasification furnace Load heating in which the heat medium heat-exchanged by a cooling device is disposed in the lower space in order to cool the melting furnace of the gasification melting furnace in which the pyrolysis gas is introduced into the molten melting furnace to generate slag And introduced into the upper space by introducing the heated air heat-exchanged by the first heat exchanger for recovering waste heat from the exhaust gas passing through the melting furnace into the upper space. A starch drying apparatus using waste heat, wherein the dried object is dried. In the starch drying apparatus using waste heat according to claim 1,
The cooling device has a water cooling jacket structure that cools the melting furnace with circulating water, and the heat medium is water,
By cooling the melting furnace, the hot water after being heat-exchanged to further cool the circulating water heated by the second heat exchanger in the load heating disposed in the lower space. A starch drying apparatus using waste heat, which is characterized by being introduced. In the starch drying apparatus using the waste heat according to claim 1 or 2,
A starch drying apparatus using waste heat, further comprising a stirring device for stirring the material to be dried accommodated in the upper space. In the starch drying apparatus using the waste heat according to any one of claims 1 to 3,
The to-be-dried material is a starch obtained by leaching fly ash collected by a bag filter constituting an exhaust gas treatment facility for treating the exhaust gas of the gasification melting furnace and / or the exhaust gas treatment facility of the gasification melting furnace. A starch drying apparatus using waste heat, characterized in that it is a neutralized starch discharged from waste water after further cooling and washing the exhaust gas treated by the above.

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