JP2002316194A - Method and apparatus for producing ground improvement material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a ground improvement material whereby long-time continuous operation of a fluidized-bed oven for drying and baking a granular material comprising a dehydrated sludge cake and lime is made possible while decreasing powdering, prolonging baking time, decreasing deposition, and maintaining a high heat efficiency and whereby the quality of a cyclone-collected material is improved. SOLUTION: A granular material comprising a dehydrated sludge cake and lime is charged into a two-chamber-type fluidized-bed drying/baking oven 20 using hot air as a fluidizing gas and the granular material itself as a fluidization medium, is dried at a bed temperature of 100 deg.C or lower in a drying chamber 26, and is subjected to the incineration of organics and the baking of lime at 900 deg.C or higher in a baking chamber 28; then, the baked granular material is introduced from the fluidized-bed oven 20 into a fluidized-bed cooler 54 to be cooled, thus giving the objective product. An exhaust gas from the fluidized-bed oven 20 is led into a cyclone 58, the temperature of the exhaust gas at the outlet of the cyclone is kept at 750 deg.C or higher, and the exhaust gas is mixed with an odor in a mixing chamber 59. A fine powder collected in the cyclone 58 is recovered as the objective product.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-chamber fluidized-bed drying and drying method in which a dewatered cake of sludge such as sewage sludge or industrial waste sludge is mixed with kneaded limes such as quicklime and slaked lime and granulated. The present invention relates to a method and an apparatus for producing a ground improvement material by putting into a firing furnace, drying in a first chamber on the upstream side, and incineration and calcination of organic matter in a second chamber on the downstream side.

[0002]

2. Description of the Related Art Sewage sludge, industrial waste sludge, etc. have been dewatered and dried and then incinerated in a fluidized bed furnace or a rotary kiln to incinerate organic matter in the sludge and landfilled. Various recycling methods for performing the above are being developed. Conventionally, as a method and apparatus for dehydrating, drying and incinerating sludge, for example, JP-A-6-15297 discloses a dehydration and drying step of mixing sludge and quicklime to dehydrate and dry sludge;
The generated solids are heated in a one-chamber fluidized bed furnace or a gas stream furnace to incinerate the organic matter in the sludge and to burn dehydrated lime by the heat of combustion of the organic matter to regenerate it into quicklime. An incineration system is disclosed.

JP-A-10-237852 discloses an organic sludge such as sewage sludge mixed with lime such as quicklime and slaked lime, and granulating the mixture to a size of 1 to 10 mm. There is disclosed a method for producing a ground improvement material by drying, dehydrating, burning organic matter, and firing slaked lime at a temperature of ~ 1000 ° C.

[0004]

The above-mentioned Japanese Patent Application Laid-Open No. 6-15 / 1994
In the sludge dewatering / drying incineration system described in Japanese Patent No. 297, the residence time in a one-chamber type fluidized bed furnace or an airflow furnace is short, so that it cannot be sufficiently fired and the performance as a ground improvement material cannot be satisfied. In addition, there is a problem that the fine powder of quicklime is re-carbonated and re-hydroxylated and adheres to the inside of the apparatus, so that long-term continuous operation cannot be performed. In addition, Japanese Patent Application Laid-Open
In the method for manufacturing a ground improvement material described in Japanese Patent No. 237852, the rotary kiln has poor heat transfer performance, so that the dry kiln only for drying, dehydration, incineration, and firing requires a large-sized apparatus. There is a problem that it adheres to the heat exchanger, hinders continuous operation, and requires a great deal of labor to remove the adhered matter.

The present invention has been made in view of the above points, and an object of the present invention is to divide a fluidized-bed furnace by a partition member.
After a granulated raw material is dried in a first room, a low-temperature room (drying room), an organic substance is incinerated and a slaked lime is decomposed in a second room, a high-temperature room (baking room).・ By performing calcination, the temperature of each chamber layer can be adjusted, less pulverization, longer calcination time, and furthermore, the exhaust gas from the fluidized bed furnace is removed by cyclone, heat exchanger, etc. It is an object of the present invention to provide a method and an apparatus for manufacturing a ground improvement material, which can greatly reduce the adhesion inside the equipment, maintain high thermal efficiency, and perform long-term continuous operation.

Another object of the present invention is to provide a mixing chamber between a cyclone and a heat exchanger, and to blow excess heating odor and normal-temperature odor or / and air into the mixing chamber to mix with the cyclone exhaust gas. The temperature of each part can be set to a temperature at which deodorization is possible and dust is not attached without deteriorating heat consumption by deodorizing by heating.In particular, the temperature of cyclone exhaust gas is set to a temperature at which fine powder products do not recarbonate. Therefore, it is an object of the present invention to provide a method and an apparatus for manufacturing a ground improvement material capable of obtaining a high-quality product because fine powder collected by a cyclone is separated from exhaust gas without recarbonation.

[0007]

Means for Solving the Problems To achieve the above object, a method for producing a soil improvement material of the present invention comprises mixing a lime into a sludge dewatered cake, stirring and granulating the granulated product from a combustion furnace. Using the hot air as a fluidizing gas and the granulated material itself as a fluidizing medium,
It is put into a two-chamber fluidized-bed drying / firing furnace partitioned by a partition member, dried in the upstream drying chamber (first chamber), and burns organic matter / lime in the downstream firing chamber (second chamber). After firing, the fired granules from the fluidized-bed drying and firing furnace are introduced into a fluidized-bed cooler or a packed-bed cooler and cooled to produce a product, while the exhaust gas from the fluidized-bed drying and firing furnace is introduced into a cyclone. After removing the dust, the exhaust gas from the cyclone is mixed with the odor in the mixing chamber, this mixed gas is introduced into a heat exchanger to recover heat, and at least a part of the fine powder collected by the cyclone passes through the cooler. , Or directly, as a product (see FIGS. 1 and 2).

[0008] In the above method, the odor generated in the process of producing the granulated product is introduced into the heat exchanger to increase the temperature, the heated odor is collected as combustion air in the combustion furnace, and the excess heated odor is removed. The air is blown into the air box and / or the mixing chamber of the drying room of the fluidized bed drying / firing furnace to deodorize. In this case, the amount of the heated odor to be blown into the combustion furnace and the amount of the heated odor to be blown into the drying chamber wind box of the fluidized bed drying / firing furnace and / or the amount of the heated odor to be blown into the mixing chamber can be adjusted. Is preferred.

Further, in the above method, the particle size of the granulated material is set to a range suitable for fluidized bed operation, from 1 to 20 mm, preferably from 2 to 20 mm.
To 10 mm. In addition, the temperature of the fluidized bed in the firing chamber was 900 ° C.
As described above, desirably, organic matter incineration and lime burning are performed at 900 to 1050 ° C. In addition, the distribution of hot air to each chamber of the fluidized bed drying / firing furnace and / or the amount of injected fuel are adjusted.

[0010] In the above method, fluidized bed drying
The superficial velocity in the drying chamber and the firing chamber of the firing furnace is adjusted to different flow rates so that each of the chambers forms a good fluidized bed. Further, in the above method, it is preferable that a normal-temperature odor and / or air different from the heating odor be introduced into the mixing chamber, and the mixing amount be adjusted. The temperature of the exhaust gas at the outlet of the mixing chamber is 600 ° C. or more, the temperature of the exhaust gas at the outlet of the cyclone is 750 ° C. or more, and the temperature of the fluidized bed in the drying chamber of the fluidized-bed drying and firing furnace is 100 ° C.
The following is assumed.

An apparatus for producing a ground improvement material according to the present invention comprises a kneading machine for kneading sludge dewatered cake and lime, a granulation machine for granulating a kneaded material, and a raw material manufacturing section. For drying, burning organic matter, and burning lime with hot air from a combustion furnace using the granulated material of
A chamber-type fluidized-bed drying and firing furnace, a fluidized-bed cooler for cooling the fired granules from the fluidized-bed drying and firing furnace, and a cyclone connected to the fluidized-bed drying and firing furnace through an exhaust gas duct. A mixing chamber connected to the cyclone via an exhaust gas duct, mixing and deodorizing by blowing the exhaust gas and odor, and a heat exchanger for introducing the exhaust gas from the mixing chamber to recover heat, and The fluidized bed drying / firing furnace is provided with a partition member in a substantially vertical direction in the fluidized bed, and is divided into an upstream drying chamber (low temperature chamber) and a downstream firing chamber (high temperature chamber). The drying of the granules is performed, and organic matter incineration and lime calcination are performed in a firing chamber. Heating odor Is introduced into the windbox of the drying chamber, it is characterized in that the remaining heating odor configured to be blown into the mixing chamber by heating odor conduit (see FIG. 1, FIG. 2).

[0012] In the above apparatus, a pipe for introducing a normal-temperature odor and / or an atmosphere other than the heated odor is connected to the mixing chamber. In addition, a heat exchanger is provided in two stages in series with the exhaust gas flow, and the odor generated during the manufacturing process of the granulated material is blown into the heat exchanger on the high temperature side, and the cooling air is blown into the heat exchanger on the low temperature side. It is preferable to adopt the configuration described above.

It is preferable that a baffle member such as a baffle plate is provided above the fluidized bed in the drying chamber of the fluidized bed drying / firing furnace so that the exhaust gas of the drying chamber and the exhaust gas of the firing chamber are mixed well. . It is preferable that the partition member for partitioning the drying chamber and the baking chamber has a height at which the granulated material overflows, and is configured such that a communication passage is provided below the partition member.

It is also possible to adopt a configuration in which the fluidized-bed cooler is of a two-chamber type, and a part of the odor is used as a cooling medium and recovered as combustion air (see FIGS. 6, 7 and 8). ). In addition, it is preferable that the heat exchanger has a structure in which a heat transfer tube for allowing odor to pass therethrough for heating is arranged substantially vertically (see FIG. 3). In addition, fluidized bed drying
A structure in which a gas dispersion plate of a baking furnace is provided with a plurality of small holes having a diameter of three times or less, and preferably two times or less, a diameter of a fluid medium in a top wall portion of a large number of cylindrical bodies fixed through the plate body. (See FIGS. 4 and 5).

Further, the mixing chamber may have a substantially cylindrical shape, and an inner cylinder may be provided to enhance the mixing property. Further, the mixing chamber may have a double air cooling structure (see FIG. 9).

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications. FIG. 1 shows an apparatus for manufacturing a ground improvement material according to a first embodiment of the present invention. Reference numeral 10 denotes a raw material (granulated material) manufacturing plant (raw material manufacturing section), which includes a kneader 12, a granulator 14, and the like. The sludge dewatered cake and limes, for example, quick lime, are put into the kneader 12 and kneaded. Quicklime absorbs water to become slaked lime, and furthermore, evaporates the water of the sludge dewatered cake by an exothermic reaction. The proportion of quicklime is selected so that the water content of the kneaded material is suitable for granulation and the granulated material has a strength that does not break in the fluidized bed. Depending on the properties of the sludge dewatered cake, for example, the water content of the kneaded material is 20 to 30%. The kneaded material is introduced into a granulator 14 and granulated to a particle size of 1 to 20 mm, preferably 2 to 10 mm. In addition, by using a kneading machine having a granulation function, it is also possible to configure so that kneading and granulation are simultaneously performed by one apparatus.

The granulated material (raw material) from the granulator 14 is temporarily stored in a hopper 16 and then supplied to a fluidized bed drying / firing furnace (hereinafter simply referred to as a fluidized bed furnace or furnace) by a feeder, for example, a belt feeder 18. 20). As shown in FIGS. 1 and 2, the fluidized bed drying / firing furnace 20 includes a fluidized bed 22 provided with a substantially vertical partition member 24, and an upstream drying chamber (first chamber) 26 and a downstream drying chamber 26. Firing chamber (second
(Room 28). 30 and 32 are burners, 3
4 is a raw material inlet.

The fluidized-bed drying / firing furnace 20 has wind boxes 38 and 40 corresponding to chambers defined below the flow box, and a granulated material serving as a fluid medium is provided above a gas dispersion plate 42 above the wind box. It is configured to form a layer 22. Hot air from a combustion furnace 44 is introduced into these wind boxes 38 and 40 as fluidized gas. Further, a part of the heated odor from a heat exchanger 46 described later can be introduced into the wind box 38 of the drying room.

A baffle member 48 such as a baffle plate is provided above the drying chamber 26 of the fluidized bed drying / firing furnace 20 so that exhaust gas from the drying chamber and exhaust gas from the firing chamber are mixed well. The partition member 24 that partitions the drying chamber 26 and the baking chamber 28 has a height at which the granules overflow, and a communication passage 50 is provided below the partition member 24.

A fluidized-bed cooler 54 is connected to the fluidized-bed drying / sintering furnace 20 via an airtight discharge mechanism, for example, an L valve 52. Fluidized bed furnace 20 has exhaust gas duct 5
The cyclone 58 is connected via the exhaust pipe 6, and an exhaust gas outlet of the cyclone 58 is connected to a mixing chamber 59. The heat exchanger 46 is connected to the exhaust gas outlet of the mixing chamber 59.
The odor from the raw material production unit 10 is introduced by the odor fan 60, and heat is exchanged with the exhaust gas from the mixing chamber 59 to increase the temperature. The mixing chamber 59 has, for example, a substantially cylindrical shape, and blows and mixes exhaust gas and odor in substantially tangential directions from opposing side surfaces, respectively, and deodorizes the odor with the heat of the exhaust gas. In this case, when the inner cylinder 61 is provided in the mixing chamber 59, the gas can be mixed well. It is also possible to make the mixing chamber cyclone-shaped so that dust can be separated from the lower part. The description of the odor introduced into the mixing chamber 59 will be described later.

The granulated material (raw material) charged into the drying chamber 26 of the fluidized bed drying / firing furnace 20 is fluidized by a fluidizing gas and adjusted to a layer temperature of 100 ° C. or less, for example, 50 to 100 ° C. dry. Burner 3 when granulated material has a lot of moisture
0 is used. The dried granules overflow the partition member 24 and move to the firing chamber 28, where incineration of organic substances is performed at a layer temperature of 900 ° C or more, preferably 900 to 1050 ° C.
The slaked lime is decomposed and fired. The communication passage 50 between the partition member 24 and the gas distribution plate 42 is for moving a lump, but, of course, the granulated material also moves. In addition,
If the calorific value is insufficient in the firing chamber 28, the burner 32
Is used.

The fired granules (mixture of incinerated ash and CaO) fired in the furnace 20 are charged into a fluidized bed cooler 54,
It is cooled directly by air or / and odor at normal temperature, discharged by a discharger, for example, a rotary feeder 62, and conveyed as a product by a transporter 64. 68 is a pushing blower, 70 is a bag filter. This bug filter 70
Is discharged to the atmosphere if it does not contain odor. In the case of exhaust gas containing odor, the exhaust gas is introduced into the combustion furnace 44, where the odor component is burned or decomposed and deodorized. In addition, it is also possible to use a packed bed cooler instead of a fluidized bed cooler.

Exhaust gas from the furnace 20 is introduced into the cyclone 58 to collect dust. This dust is collected as a fine powder product, for example, put into a fluidized bed cooler 54, cooled, and then sent to a product tank. In this case, the exhaust gas temperature at the outlet of the cyclone 58 is adjusted to be 750 ° C. or higher. If the cyclone outlet gas temperature is lower than 750 ° C., CaO contained in the dust (fine powder) absorbs CO ₂ in the exhaust gas to become CaCO ₃ , and the recarbonation lowers the quality of the fine powder product. .

The exhaust gas from the cyclone 58 is mixed with the odor in the mixing chamber 59 and introduced into the heat exchanger at 600 ° C. or higher. The heat exchanger is preferably provided in two stages in series with the exhaust gas flow. Hereinafter, a case where the heat exchanger is provided in two stages will be described. The odor generated in the raw material manufacturing plant 10 is introduced into the heat exchanger 46 on the high temperature side by the odor fan 60, and the cooling air (atmosphere) is introduced into the heat exchanger 72 on the low temperature side by the pushing blower 74. The exhaust gas from the heat exchanger 72 on the low temperature side is exhausted by the exhaust gas induction fan 7.
6, the dust is introduced into the bag filter 78, where the dust is separated, and then discharged from the chimney 80.

The odor heated by the heat exchanger 46 on the high temperature side is recovered as combustion air in the combustion furnace 44, and the excess heated odor is blown into the wind box 38 of the drying chamber 26 of the furnace 20 to burn the odor. The remaining heated odor introduced into the furnace 44 and the wind box 38 of the drying chamber in a required amount is blown into the mixing chamber 59, and the odor components are burned or decomposed and deodorized at each location. In this case, the distribution of the amount of hot air and the amount of fuel injected into each chamber of the furnace 20 are adjustable, and the superficial velocity in the drying chamber 26 and the baking chamber 28 is different from each other so that each chamber forms a good fluidized bed. It is preferable to adjust to. In addition, the branch pipes 84 and 86 of the heating odor from the heat exchanger 46,
88 are provided with valves 90, 92, 94, respectively, for blowing the heated odor into the combustion furnace 44, blowing the heated odor into the wind box 38 of the drying chamber 26, and feeding the heated odor to the mixing chamber 59. It is configured such that the blowing amount of each can be adjusted.

In addition to the heating odor, odor at room temperature and / or air (atmosphere) is introduced into the mixing chamber 59 so that the exhaust gas temperature at the outlet of the mixing chamber 59 becomes 600 ° C. or more. Then, the blowing amount is adjusted. 82 is a pushing blower and 95 is a valve. If the outlet temperature of the mixing chamber 59 is adjusted to 600 ° C. or higher, deodorization can be reliably performed without deterioration of heat consumption, and there is no problem of dust adhesion.

In the above apparatus, the heat exchangers 46, 72
As shown in FIG. 3, it is preferable to use a structure in which a heat transfer tube 96 for passing an odor and heating it is arranged vertically. With this configuration, the amount of dust attached and deposited is small, and cleaning is easy. It is preferable that the low-temperature side heat exchanger 72 has the same structure.

Further, as the gas dispersion plate 42 of the fluidized-bed drying and firing furnace 20, for example, a dispersion plate having a special structure as disclosed in Japanese Utility Model Publication No. 7-37113 is preferable. As shown in FIGS. 4 and 5, the dispersion plate having this special structure has a diameter of not more than three times the diameter of the flowing medium, preferably not more than the diameter of the fluid medium, on the top wall portion 102 of a large number of cylindrical bodies 100 fixedly penetrating the plate body 98. It is provided with a plurality of small holes 104 of twice or less. By using the dispersion plate having such a structure, hot banking in which the fluid medium is maintained at a high temperature becomes possible. The auxiliary burners 30 and 32 provided near the upper side of the gas distribution plate 42 can deodorize the odor at the time of startup, in addition to supplementing the insufficient fuel.

As described above, the present invention is characterized in that a two-chamber fluidized bed drying / firing furnace 20 is used. In the case of a one-chamber fluidized-bed furnace, a granulated material having a water content of 25 to 30% is introduced into a high-temperature fluidized bed. Sintering, resulting in insufficient firing. However, when only the granulated material is dried by adjusting the bed temperature to 50 to 100 ° C. in a drying chamber in a two-chamber fluidized bed furnace, the granulated material hardly powders in the drying chamber, and Powdering is also greatly reduced. Although the powdering rate is substantially proportional to the flow rate (superficial velocity), the flow rate can be reduced because the calcined product is lighter than the wet raw material.

Further, in order to deodorize the exhaust gas in the drying chamber 26, it is necessary to improve the mixing between the dried exhaust gas and the high-temperature exhaust gas in the firing chamber 28. Therefore, by providing a baffle member (for example, baffle plate) 48 above the drying chamber 26, the odor from the drying chamber 26 can be surely deodorized.

When the firing temperature in the firing chamber 28 of the furnace 20 is adjusted to 900 to 1050 ° C. and the outlet gas temperature of the cyclone 58 is adjusted to 750 ° C. or more, the quality and deodorization of the fine powder product collected by the cyclone can be operated without any problem. be able to. By setting the cyclone outlet gas temperature to 750 ° C. or higher so that the fine powder does not recarbonate, the quality of the cyclone collection product can be improved. Further, when the gas temperature at the cyclone outlet is set to 750 ° C. or more, there is no problem of adhesion in the cyclone.

When an odor is blown into the fluidized bed cooler 54 as cooling air and is recovered as combustion air in the combustion furnace 44, heat is recovered by the cooler 54 to further reduce fuel cost. Dust collected by the bag filter and unburned dust generated in a raw material factory, a baking factory, and the like can be collected as a product by being put into the baking chamber 28 of the fluidized bed furnace 20 and baking. In addition, by blowing excess heating odor and room temperature odor or / and atmosphere into the mixing chamber 59 and mixing with the exhaust gas from the cyclone 58 for deodorization, heat consumption is not deteriorated.
The temperature of each part can be set to a temperature where deodorization is possible and there is no dust adhesion.

FIG. 6 shows the surroundings of a fluidized-bed cooler in an apparatus for manufacturing a ground improvement material according to a second embodiment of the present invention. In this embodiment, a two-chamber fluidized bed cooler 106 is used, wind boxes 108 and 110 are provided corresponding to each chamber, odor is introduced into the upstream wind box 108, and the downstream wind box 110 is cooled. The odor from the first chamber 112 is introduced into the cyclone 114 to remove dust by introducing air for use, the odor is supplied to the combustion furnace 44, and the dust is introduced into the second chamber 116, and the second chamber 116 is charged. The exhaust gas from 116 is introduced into the cyclone 118. Reference numeral 120 denotes a partition, 122 denotes an odor pushing blower, 124 denotes an air pushing blower, 126 denotes a rotary feeder, and 128 denotes a transport machine. As described above, the fluidized-bed cooler is made into a two-chamber type, and the odor is blown into the first chamber (high-temperature side) and is recovered as combustion air of the combustion furnace, so that heat is recovered in the fluidized-bed cooler and fuel cost is reduced. It can be further reduced. Other configurations and operations are the same as those in the first embodiment.

FIG. 7 shows the surroundings of a fluidized-bed cooler in an apparatus for manufacturing a ground improvement material according to a third embodiment of the present invention. In the present embodiment, a two-chamber fluidized bed cooler 106 is used, wind boxes 108 and 110 are provided for each chamber, exhaust gas from the cyclone 118 is introduced into the upstream wind box 108, and the downstream wind An odor is introduced into the box 110. Note that a cyclone for removing exhaust gas from the first chamber 112 is omitted. As described above, the fluidized-bed cooler is of the two-chamber type, the odor is blown into the second chamber (low-temperature side), the exhaust gas of the second chamber is used as cooling air for the first chamber, and then recovered as combustion air for the combustion furnace. By doing so, heat is recovered in the fluidized-bed cooler, and the fuel cost can be further reduced. Other configurations and operations are the same as those in the first and second embodiments.

FIG. 8 shows the surroundings of a fluidized bed cooler in an apparatus for manufacturing a ground improvement material according to a fourth embodiment of the present invention. In the present embodiment, a two-chamber fluidized bed cooler 130 is used, and the wind box 132 of each chamber is made common without being divided, and odor is introduced into the wind box 132 so as to introduce odor into the first chamber 11.
2 to the cyclone 114 to remove dust,
The exhaust odor is supplied to the combustion furnace 44, dust is introduced into the second chamber 116, and the exhaust odor from the second chamber 116 is removed from the bag filter 13.
4, the bag filter exhaust gas is supplied to the heat exchanger 46. As described above, the fluidized-bed cooler is a two-chamber type, odors are blown into the first and second chambers, the exhaust gas from the first chamber is collected as combustion air for the combustion furnace, and the exhaust gas from the second chamber is cooled by the heat exchanger. After being used as the air for use, by collecting the air in the wind box or the freeboard section, heat is recovered in the fluidized bed cooler, and the fuel cost can be further reduced. Other configurations and operations are the same as those in the first and second embodiments.

FIG. 9 shows an apparatus for manufacturing a ground improvement material according to a fifth embodiment of the present invention. In this embodiment, a mixing chamber 59a having a double air cooling structure is used, and the amount of air can be adjusted so that the outlet gas temperature becomes 600 ° C. or higher. 136 is an air push blower, 13
8 is a jacket. Other configurations and operations are the same as those of the first embodiment.
This is the same as in the case of the form.

[0037]

As described above, the present invention has the following effects. (1) Since a two-chamber fluidized bed drying and firing furnace is used to dry pre-granulated raw materials, incinerate organic substances, and decompose and burn slaked lime in separate chambers, the bed temperature in each chamber can be easily adjusted. , The powdered granules are less powdered, and the firing time is longer. For this reason, the rotary kiln conventionally required is not required. (2) Since the raw material is a granulated material, the granulated material itself becomes a fluid medium, and another fluid medium is unnecessary. In addition, a small-sized, high-efficiency fluidized-bed cooler or packed-bed cooler can be used as the cooler. (3) Since the exhaust gas from the fluidized bed furnace is removed by a cyclone, adhesion in the downstream heat exchanger is greatly reduced, and good thermal efficiency can be maintained, and long-term continuous operation can be performed. (4) Since the temperature of the exhaust gas at the cyclone outlet is set to a temperature (750 ° C. or higher) at which re-carbonation of the fine powder product does not occur,
The quality of the fine powder product collected by the cyclone can be improved. Further, when the gas temperature at the cyclone outlet is set to 750 ° C. or more, there is no problem of adhesion in the cyclone. (5) Since the distribution of the odor is adjusted and the excess odor is deodorized in the mixing chamber, the temperature of each part can be set to a deodorizable and dust-free temperature without deteriorating heat consumption. (6) When two stages of heat exchangers are used, the amount of heat recovery is reduced, but the size of the device can be reduced (the heat transfer area is reduced to 1/3 to 1/4) and the amount of cooling air is adjusted. By doing so, the exhaust gas temperature can be kept constant. Therefore, the downstream bag filter can be protected, and stable operation can be continued. (7) When a baffle member (for example, a baffle plate) is provided above the drying chamber of the fluidized bed furnace, the baffle member improves the mixing between the exhaust gas from the drying chamber and the exhaust gas from the firing chamber, and can reliably deodorize. (8) When the height of the partition member of the fluidized-bed furnace is set to the height at which the granulated material overflows, it is not necessary to adjust the bed height of the drying chamber due to the overflow. Stable operation can be easily performed without stagnation. (9) There is almost no scattering from the drying chamber in the fluidized bed furnace, the scattering dust is fired in the free board part, and the cyclone trapping powder is separated from the exhaust gas at a temperature that does not cause re-carbonation, so a high quality product Is obtained. (10) When a two-chamber fluidized bed cooler is used, heat consumption can be further reduced. (11) When a heat exchanger in which the heat transfer tubes are arranged vertically is used, dust is less likely to adhere and accumulate and cleaning is easy. (12) When a dispersion plate having a special structure is used, hot banking can be performed. Therefore, starting and stopping can be performed in a very short time, and the operation at the time of abnormality is easy. (13) When an inner cylinder is provided in the mixing chamber,
The mixture of the exhaust gas and the odor becomes good, and the deodorization can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a systematic schematic configuration diagram showing an apparatus for manufacturing a ground improvement material according to a first embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional explanatory view of the fluidized bed drying / firing furnace in FIG.

FIG. 3 is an explanatory sectional view showing an example of the heat exchanger in FIG. 1;

FIG. 4 is an explanatory sectional view showing an example of a gas dispersion plate of the fluidized-bed drying / firing furnace in FIG. 1;

FIG. 5 is a plan view of a main part of the gas dispersion plate in FIG.

FIG. 6 is a schematic configuration diagram around a fluidized-bed cooler in an apparatus for manufacturing a ground improvement material according to a second embodiment of the present invention.

FIG. 7 is a schematic configuration diagram around a fluidized bed cooler in an apparatus for manufacturing a ground improvement material according to a third embodiment of the present invention.

FIG. 8 is a schematic configuration diagram around a fluidized-bed cooler in an apparatus for manufacturing a ground improvement material according to a fourth embodiment of the present invention.

FIG. 9 is a systematic schematic configuration diagram of an apparatus for manufacturing a ground improvement material according to a fifth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Raw material manufacturing plant (raw material manufacturing part) 12 Kneader 14 Granulator 16 Hopper 18 Belt feeder 20 Fluidized bed drying / firing furnace (fluidized bed furnace) 22 Fluidized bed 24 Partition member 26 Drying room (first room, low temperature room) 28 firing chamber (second chamber, high temperature chamber) 30, 32 burner 34 raw material inlet 38, 40 wind box 42 gas dispersion plate 44 combustion furnace 46, 72 heat exchanger 48 baffle member such as baffle plate 50 communication passage 52 L valve 54 Fluidized bed cooler 56 Exhaust gas duct 58 Cyclone 59, 59a Mixing chamber 60 Odor fan 61 Inner cylinder 62 Rotary feeder 64 Transport machine 68, 74, 82 Push blower 70, 78 Bag filter 76 Exhaust gas inducing fan 80 Chimney 84, 86, 88 Branch pipe 90, 92, 94, 95 Valve 96 Heat transfer tube 98 Plate 100 Cylindrical 102 Top wall Part 104 Small hole 106, 130 Two-chamber fluidized bed cooler 108, 110, 132 Wind box 112 First chamber 114, 118 Cyclone 116 Second chamber 120 Partition 122 Odor pushing blower 124, 136 Air pushing blower 126 Rotary feeder 128 Transportation Machine 134 Bag filter 138 Jacket

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Mikio Murao 35th floor, Nishimachi, Chuo-ku, Kobe Mitsui Nissei Kobe Bldg. 3F Kawatera Staff Co., Ltd. F term (reference) 2D043 CA01 EA04 3L113 AA07 AB03 AB04 AC04 AC45 AC46 AC50 AC56 AC61 AC67 AC73 AC83 AC87 BA37 DA02 DA13 DA14 DA24 4D059 AA30 BB02 BB06 BB13 BB18 BD03 BG00 BJ00 BK09 CA10 CA16 CB30 CC10 DA04 EB06 EB07 EB10

Claims (19)

[Claims] 1. A granulated material obtained by mixing and agitating lime into a sludge dewatered cake and granulating the granulated material, and using a hot air from a combustion furnace as a fluidizing gas, and using the granulated material itself as a fluid medium, divided by a partition member. After being placed in a chamber-type fluidized bed drying / firing furnace, drying is performed in the upstream drying chamber, organic matter incineration / lime calcination is performed in the downstream firing chamber, and then the granulated particles from the fluidized bed drying / firing furnace are fired. The product is introduced into a fluidized bed cooler or a packed bed cooler and cooled to produce a product.On the other hand, the exhaust gas from the fluidized bed drying / firing furnace is introduced into a cyclone to remove dust, and then the exhaust gas from the cyclone is mixed with odor in a mixing chamber. Then, the mixed gas is introduced into a heat exchanger to recover heat, and at least a part of the fine powder collected by the cyclone is passed through the cooler or directly, as a soil improvement material characterized by being recovered as a product. Production method. 2. The odor generated in the process of producing the granulated product is introduced into a heat exchanger to raise the temperature, and the heated odor is recovered as combustion air in a combustion furnace. The method for producing a ground improvement material according to claim 1, wherein the air is blown into a wind box and / or a mixing chamber of a drying room of the firing furnace to deodorize. 3. The amount of the heated odor blown into the combustion furnace and the amount of the heated odor blown into the drying chamber wind box of the fluidized bed drying / firing furnace and / or the amount of the heated odor blown into the mixing chamber are adjusted. A method for producing the ground improvement material according to claim 2. 4. The method for producing a ground improvement material according to claim 1, wherein the granulated material has a particle size of 1 to 20 mm. 5. The method for producing a ground improvement material according to claim 1, wherein the incineration of organic matter and lime calcination are performed by setting the fluidized bed temperature of the sintering chamber to 900 ° C. or higher. 6. The method for producing a ground improvement material according to claim 1, wherein the amount of hot air distributed to each chamber of the fluidized bed drying / firing furnace and / or the amount of fuel injected are adjusted. 7. The method according to claim 1, wherein the superficial velocity in the drying chamber and the firing chamber of the fluidized-bed drying / firing furnace is adjusted to different flow rates so that each of the chambers forms a good fluidized bed. A method for producing the ground improvement material as described above. 8. The method for producing a ground improvement material according to claim 2, wherein a normal-temperature odor and / or air other than the heated odor is introduced into the mixing chamber, and the blowing amount is adjusted. 9. The exhaust gas temperature at the outlet of the mixing chamber is 600 ° C. or more, and the exhaust gas temperature at the outlet of the cyclone is 750 ° C.
The method for producing a ground improvement material according to any one of claims 1 to 8, wherein the fluidized bed temperature in the drying chamber of the fluidized bed drying / firing furnace is 100 ° C or lower. 10. A raw material production section comprising a kneader for kneading sludge dewatered cake and lime, a granulator for granulating the kneaded material, and granulation from the raw material production section. A two-chamber fluidized-bed drying and firing furnace for drying, burning organic matter, and burning lime with hot air from a combustion furnace using the material as a fluidized medium, and for cooling the fired granules from the fluidized-bed drying and firing furnace. A fluidized bed cooler, a cyclone connected to a fluidized bed drying / sintering furnace via an exhaust gas duct, and a mixing chamber connected to the cyclone via an exhaust gas duct for blowing and mixing odors with the exhaust gas for deodorization. A heat exchanger for introducing exhaust gas from the mixing chamber and recovering heat therefrom, wherein the fluidized bed drying / sintering furnace is provided with a substantially vertical partition member in the fluidized bed, and has an upstream drying chamber and a downstream drying chamber. Side firing room The granulated material is dried in the drying chamber, the organic matter is incinerated and lime is calcined in the firing chamber, and the odor generated during the manufacturing process of the granulated material is generated in the heat exchanger. The heating odor is introduced into the mixing chamber by the odor conduit, the heated odor is introduced into the combustion chamber and the wind box of the drying chamber, and the remaining odor is blown into the mixing chamber by the heating odor conduit. Equipment for manufacturing ground improvement materials. 11. An apparatus for manufacturing a ground improvement material according to claim 10, wherein a pipe for introducing a normal-temperature odor and / or an air other than the heating odor is connected to the mixing chamber. 12. A heat exchanger is provided in two stages in series with respect to the exhaust gas flow, and the odor generated during the manufacturing process of the granulated material is blown into the heat exchanger on the high temperature side, and the cooling air is supplied to the heat exchanger on the low temperature side. The apparatus for manufacturing a ground improvement material according to claim 10 or 11, wherein the air is blown. 13. A baffle member such as a baffle plate is provided above a fluidized bed in a drying chamber of a fluidized bed drying / firing furnace so that exhaust gas from the drying chamber and exhaust gas from the firing chamber are mixed well. 13. An apparatus for manufacturing a ground improvement material according to item 12. 14. The partitioning member for partitioning the drying chamber and the baking chamber has a height at which the granulated material overflows, and a communication passage is provided below the partitioning member. 2. A manufacturing apparatus for a ground improvement material according to claim 1. 15. The apparatus for manufacturing a soil improvement material according to claim 10, wherein the fluidized bed cooler is a two-chamber type, and a part of the odor is used as a cooling medium and recovered as combustion air. 16. The apparatus for manufacturing a ground improvement material according to claim 10, wherein the heat exchanger has a structure in which heat transfer tubes for passing odor and heating the heat exchanger are arranged substantially vertically. 17. The gas dispersion plate of a fluidized bed drying / firing furnace,
The ground according to any one of claims 10 to 16, wherein a plurality of small holes each having a diameter of three times or less the diameter of the fluid medium are provided in a top wall portion of a large number of cylindrical bodies fixed through the plate body. Equipment for manufacturing improved materials. 18. The mixing chamber has a substantially cylindrical shape,
The apparatus for manufacturing a ground improvement material according to any one of claims 10 to 17, wherein an inner cylinder is provided to enhance mixing properties. 19. The apparatus for manufacturing a ground improvement material according to claim 10, wherein the mixing chamber has a double air cooling structure.