Carbide treatment device and carbide treatment method

Abstract

To provide a carbonized material treatment apparatus and a carbonized material treatment method that realize energy saving.SOLUTION: A carbonized material treatment apparatus 100 comprises: a drying treatment section D that performs finish drying while pre-dried carbonization target material is stacked in layers to obtain finish-dried carbonization target material; and a carbonization treatment section 6 that carbonizes the carbonization target material finish-dried in the drying treatment section D, to produce fuel, wherein the drying treatment section D includes: a gas passage section 17 configured to pass drying gas G3 from a lower portion of a stacked layer B of the carbonization target material; and a discharge section 14 configured to supply the carbonization target material at the lower portion of the stacked layer B to the carbonization treatment section 6.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a carbide processing device and a carbide processing method. [Background technology]

[0002] Organic waste (material to be carbonized) such as sewage sludge is dehydrated and dried, then carbonized in a heating furnace or the like, and reused as fuel (see, for example, Patent Document 1).

[0003] Patent Document 1 describes a biomass char production system (an example of a char treatment device) that carbonizes wet biomass (organic matter-containing sludge, an example of a material to be carbonized) generated during wastewater treatment or the like to obtain biomass char. This system includes a dehydration device that dehydrates wet biomass such as sewage sludge, a drying treatment section that dries the wet biomass dehydrated in the dehydration device to produce dried biomass, a carbonization treatment section that carbonizes the dried biomass supplied from the drying treatment section to produce biomass char, a pyrolysis gas incineration section that combusts and incinerates pyrolysis gas generated in the carbonization treatment section, and a control device for controlling operation. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-137739 Summary of the Invention [Problem to be solved by the invention]

[0005] When carbonizing a material to be carbonized, the lower the moisture content of the material, the less heat energy is required for carbonization, resulting in energy savings for the system. However, with conventional carbonized material processing devices, attempts to sufficiently dry the material can result in the material being pulverized, which can lead to problems such as reduced handleability. Therefore, conventional carbonized material processing devices must reduce the moisture content of the material while suppressing pulverization, leaving room for further energy savings.

[0006] The present invention has been made in view of the above circumstances, and its object is to provide a carbide processing apparatus and a carbide processing method that realize energy saving. [Means for solving the problem]

[0007] The characteristic configuration of the carbide treatment apparatus according to the present invention for achieving the above object is as follows: The moisture content is 5% by weight or more and 25% by weight or less The system comprises a drying processing section in which pre-dried carbonization objects are stacked in layers and subjected to finish-drying to obtain finish-dried carbonization objects, and a carbonization processing section in which the carbonization objects that have been finish-dried in the drying processing section are carbonized to produce fuel, and the drying processing section has an aeration section that vents drying gas from the bottom of the stacked layer of carbonization objects, and a discharge section that supplies the carbonization objects at the bottom of the stacked layer to the carbonization processing section.

[0008] The carbide processing method according to the present invention for achieving the above object is characterized by the following features: The moisture content is 5% by weight or more and 25% by weight or less The method includes a drying process step in which pre-dried carbonization objects are stacked in layers and then finish-dried to obtain finish-dried carbonization objects, and a carbonization process step in which the carbonization objects that have been finish-dried in the drying process step are carbonized to produce fuel, and the drying process step includes an aeration step in which a drying gas is ventilated from the bottom of the stacked layer of carbonization objects, and a cutting step in which the carbonization objects at the bottom of the stacked layer are cut out.

[0009] According to each of the above configurations, the pre-dried material to be carbonized is finish-dried in a drying processing unit. By performing drying in two stages, pre-drying and finish-drying, drying conditions can be set appropriately for the moisture content of the material to be carbonized, such that if the moisture content of the material to be carbonized is high, drying conditions are adjusted accordingly, and if the moisture content of the material to be carbonized is lower than expected in the pre-drying, drying conditions are adjusted accordingly. This allows the material to be sufficiently dried, reducing the thermal energy required for the carbonization process (realizing energy saving).

[0010] According to the above configurations, the materials to be carbonized are finished and dried in a layered state, i.e., in a stationary layer state. This prevents the materials from moving and colliding with each other due to this movement, resulting in powdering. This prevents problems in the carbonization process caused by powdering and achieves energy savings.

[0011] According to each of the above configurations, during finish drying, a drying gas is passed through the bottom of the sedimentary layer of material to be carbonized (hereinafter simply referred to as the sedimentary layer). This ventilation allows the drying of the carbonized material in the sedimentary layer to proceed from the bottom. That is, during finish drying, the lower layer of the sedimentary layer becomes dry, while the upper layer, including the surface layer, maintains a relatively high moisture content. As a result, during finish drying, the surface of the sedimentary layer is covered with material to be carbonized, which has a high moisture content. Therefore, even if fine particles of the material to be carbonized (e.g., fine particles resulting from powdering in the lower layer of the sedimentary layer) migrate to the upper layer of the sedimentary layer accompanied by the flow of the drying gas, they are captured by the material to be carbonized in the upper layer of the sedimentary layer, which has a high moisture content (adhering by so-called liquid bridges), thereby preventing dust generation from the sedimentary layer.

[0013] A further characteristic feature of the carbonized material processing apparatus according to the present invention is that the drying processing section has a preliminary dryer that pre-dries the material to be carbonized, and a main dryer that performs the finish drying.

[0014] A further characteristic feature of the carbonized material processing device of the present invention is that it further comprises a combustion section that burns exhaust gas discharged from the carbonization processing section, and the pre-dryer pre-dries the carbonized material using the combustion exhaust gas from the combustion section as a heat source.

[0015] A further characteristic feature of the carbonized material processing device according to the present invention is that it further comprises a deodorizing section that deodorizes the exhaust gas discharged from the drying processing section, and the combustion section combusts the exhaust gas discharged from the carbonization processing section and the exhaust gas discharged from the preliminary dryer. [Effects of the Invention]

[0016] It is possible to provide a carbide processing apparatus and a carbide processing method that achieve energy savings. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram illustrating the configuration of an organic sludge recycling system. [Figure 2] FIG. 2 is a diagram illustrating the configuration of a second dryer. DETAILED DESCRIPTION OF THE INVENTION

[0018] A carbide processing apparatus and a carbide processing method according to an embodiment of the present invention will be described with reference to the drawings.

[0019] (Overall configuration) 1 shows a carbide treatment apparatus 100 according to this embodiment. The carbide treatment apparatus 100 carbonizes organic sludge such as sewage sludge as a carbonization target to produce fuel (carbide).

[0020] As shown in Figure 1, the carbonized material processing device 100 is equipped with a drying processing unit D (an example of a drying processing step) that includes a pre-dryer 3 (an example of a first dryer, an example of a first drying step) that dries the dehydrated material L1, which is obtained by dehydrating organic sludge using a filter press or the like, with high-temperature hot air G1, a storage tank 4 that temporarily stores the pre-dried product L2 pre-dried in the pre-dryer 3, a granulator 5 that granulates the pre-dried product L2 using an extrusion granulation method or the like, and a main dryer 1 (an example of a second dryer, an example of a second drying step) that finish-dries the granulated material P granulated in the granulator 5 in a layered state. The carbonized material processing apparatus 100 also includes a carbonization furnace 6 (an example of a carbonization processing section and an example of a carbonization processing step) that carbonizes the dried granules Pd dried in the dryer 1; a combustion furnace 7 (an example of a combustion section and an example of a combustion step) that combusts the first dried exhaust gas G2 from the pre-dryer 3 and the dry distillation gas F from the carbonization furnace 6 using the heat of a separately supplied fuel and supplies heat to the pre-dryer 3; and a control unit 9 including a CPU that controls the operation of the drying processing section D, the carbonization furnace 6, and the combustion furnace 7. The dehydrated material L1, the pre-dried product L2, the granulated material P, and the dried granules Pd are conveniently distinguished from each other by the organic sludge to be carbonized according to its state in each process. Hereinafter, when the dehydrated material L1, the pre-dried product L2, the granulated material P, and the dried granules Pd are collectively referred to as the "carbonization target," they will simply be referred to as the "carbonization target."

[0021] In the carbonized material processing apparatus 100, the material to be carbonized is transported in the order of preliminary dryer 3, storage tank 4, granulator 5, main dryer 1, and carbonization furnace 6, and after being carbonized in carbonization furnace 6, is transported to the next process as carbonized material M. Hereinafter, the upstream and downstream sides of the transport path of the material to be carbonized will be simply referred to as "upstream" or "upstream side" and "downstream" or "downstream side," respectively.

[0022] (Explanation of carbide treatment equipment) The following provides a detailed description of the carbide processing apparatus 100. As described above, the carbide processing apparatus 100 includes the drying processing section D, the carbonization furnace 6, and the combustion furnace 7, and is an apparatus for drying the material to be carbonized in the drying processing section D and further carbonizing it in the carbonization furnace 6 to obtain the carbide M.

[0023] (Combustion furnace) The combustion furnace 7 has a burner that burns the supplied fuel and generates high-temperature combustion exhaust gas Ex1. As described above, the combustion furnace 7 is a heat source that generates heat by burning the carbonization gas F together with the fuel, and also a purification device that combusts and removes combustible gases and odorous components contained in the carbonization gas F and the first drying exhaust gas G2. Since combustion in the combustion furnace 7 occurs at a combustion temperature exceeding 600°C, if the carbonization gas F is contaminated with fine particles containing nitrogen components, such as the carbonization target, combustion in the combustion furnace 7 may cause the generation of nitrogen oxides and cyanide compounds. Therefore, in this embodiment, the incorporation of fine particles into the carbonization gas F is suppressed, as will be described later.

[0024] (Drying processing section) In the drying section D, the dehydrated matter L1 is dried to obtain dried granules Pd. The drying section D has the preliminary dryer 3, the storage tank 4, the granulator 5, and the main dryer 1 as described above.

[0025] (Pre-dryer) The preliminary dryer 3 is a hot air dryer that dries the dehydrated material L1 using the combustion exhaust gas Ex1 from the combustion furnace 7 as a heat source to obtain a pre-dried product L2. The preliminary dryer 3 is a hot air dryer that dries the dehydrated material L1 by bringing the dehydrated material L1 into solid-gas contact with the drying hot air G1. The first dried exhaust gas G2 from the preliminary dryer 3 is sent to the combustion furnace 7, where the contained odorous gases and flammable gases are burned and removed. Note that the first dried exhaust gas G2 may be sent to the combustion furnace 7 after the pre-dried product L2 mixed in the first dried exhaust gas G2 is collected by a collector (not shown) such as a cyclone. The pre-dried product L2 is transported to the downstream storage tank 4 by a transport device such as a flight conveyor.

[0026] The preliminary dryer 3 takes in combustion exhaust gas Ex1 from the exhaust pipe of the combustion furnace 7 through a valve 37 with the flow rate adjusted, and mixes this taken in combustion exhaust gas Ex1 with first drying exhaust gas G2, which is taken in from the exhaust pipe of the preliminary dryer 3 through a valve 31 with the flow rate adjusted, and adjusts the temperature to 250°C to 850°C to use as hot air G1.

[0027] In the preliminary dryer 3, the pre-dried product L2 is dried so that its moisture content is 5% by weight or more and 25% by weight or less, preferably 5% by weight or more and 10% by weight or less. By keeping the moisture content of the pre-dried product L2 at 5% by weight or more and 25% by weight or less, the drying in the preliminary dryer 3 can be carried out safely, and granulation in the granulator 5, which will be described later, can be facilitated.

[0028] If the moisture content of the pre-dried product L2 is less than 5% by weight, it may be difficult to granulate the pre-dried product L2 in the granulator 5 described below, or the pre-dried product L2 may not be granulated properly. Furthermore, the pre-dried product L2 may be partially scorched by the hot air G1, increasing the risk of ignition or fire. If the moisture content of the pre-dried product L2 exceeds 25% by weight, blocking may occur during primary storage in the storage tank 4 described below, or granules granulated in the granulator 5 described below may easily aggregate, and the energy-saving effect of the carbonization process may be reduced.

[0029] (storage tank) The storage tank 4 is a hopper having a container portion for storing the pre-dried product L2. The storage tank 4 temporarily stores the pre-dried product L2 in order to supply it downstream in accordance with the processing capacity of the downstream device. The storage tank 4 has a powder / granular material discharge (feed) device such as a rotary valve, screw feeder, or table feeder at the bottom of the container body that stores the pre-dried product L2 in layers, and discharges the pre-dried product L2 from the storage tank 4 and supplies it downstream.

[0030] (granulator) The granulator 5 is a device that granulates the pre-dried product L2 into granules to obtain the granulated product P. The granulator 5 may be a device that realizes various granulation methods, such as stirring granulation, rolling granulation, or extrusion granulation. In this embodiment, an extrusion granulator is used as the granulator 5, which is capable of extruding the pre-dried product L2 through a screen with multiple circular openings using a screw or the like and cutting it to a predetermined length to obtain cylindrical granules with a length and diameter of approximately several millimeters.

[0031] (Second dryer) 1 and 2, the dryer 1 includes a drying tank 10 in which the granulated material P is stored and dried in a layered state to obtain dried granules Pd, an aeration section 17 (an example of an aeration step) that vents a drying gas G3 from below the sedimentary layer B of the granulated material P in the dryer 1, and a deodorization section 8 (an example of a deodorization step) that purifies the second drying exhaust gas G4 from the dryer 1 by deodorizing it, etc. The dryer 1 dries the dried granules Pd so that the moisture content thereof becomes 10% by weight or less.

[0032] 2, the drying tank 10 is a storage container made of metal such as stainless steel, which includes an upper container 11 having a top plate at the top end and a cylindrical body, and a lower container 12 that is continuous with the lower part of the upper container 11, has a circular cross section, and is cone-shaped and narrows toward the bottom. The lower container 12 may also be formed in a cylindrical shape, and is not particularly limited thereto.

[0033] The drying tank 10 is connected to a supply section 13 for feeding the granulated material P into the drying tank 10, a discharge section 14 for discharging the dried granules Pd from the upper container 11 and supplying them to the carbonization furnace 6 (see Figure 1), a gas inlet section 18 for introducing a drying gas G3 into the drying tank 10, and an exhaust section 19 for exhausting a second drying exhaust gas G4 from the drying tank 10.

[0034] The supply unit 13 is a powder / granular material supply device having, for example, a rotary valve. The supply unit 13 is provided on the top plate of the upper container 11, and supplies the granulated material P supplied from the upstream side of the dryer 1 into the drying tank 10 from above. This causes the granulated material P to be stacked in layers inside the drying tank 10. The supply unit 13 may be provided with a buffer tank upstream of the rotary valve for temporarily storing the granulated material P supplied from the upstream side of the dryer 1.

[0035] The discharge unit 14 is a powder / granular material discharge (supply) device such as a rotary valve or a table feeder, whose horizontal cross-sectional diameter is slightly larger than that of the supply unit 13. The discharge unit 14 is connected to the lower end of the lower container 12, and while maintaining the layer state of the sediment layer B to some extent, cuts out the dried granules Pd from the bottom of the sediment layer B, discharges them from the drying tank 10, and supplies them downstream (an example of a cutting step).

[0036] The gas introduction part 18 is an inlet for introducing the drying gas G3 into the drying chamber 10, and has one end connected to the lower end portion of the lower container 12 and a short pipe for introducing (supplying) the drying gas G3 into the chamber (sediment layer B) of the drying chamber 10. The other end of the gas introduction part 18 is connected to the vent part 17, and the drying gas G3 is supplied from the vent part 17.

[0037] The ventilation unit 17 is a temperature control and air supply mechanism that includes a blower or compressor (not shown) that blows the drying gas G3 and a heat exchanger (not shown) that regulates (heats) the temperature of the drying gas G3, and supplies the drying gas G3 to the drying tank 10. The ventilation unit 17, for example, draws in outside air, heats it to 40°C to 100°C, and supplies it as the drying gas G3 to the drying tank 10 at an air volume that allows the sediment layer B to maintain a stationary state (for example, an air volume that provides a superficial velocity of 0.001 to 0.4 m / s in the upper container 11). Note that "the sediment layer B maintains a stationary state" means that the sediment layer B is not fluidized by the ventilation of the drying gas G3 and is a stationary layer; downward movement of the layer accompanying the discharge of the dry granules Pd from the discharge unit 14 is not included in the fluidization. In this embodiment, the volume of air drawn in from the ventilation section 17 or the superficial velocity of the upper container 11 is maintained within a range in which the sediment layer B remains stationary even if the discharge of the dry granules Pd from the discharge section 14 is stopped.

[0038] The exhaust unit 19 has one end connected to the top plate of the upper container 11 and has a short pipe that exhausts the second drying exhaust gas G4 from inside the drying tank 10. The other end of the exhaust unit 19 is connected to the deodorizing unit 8 and blows the second drying exhaust gas G4 toward the exhaust unit 19.

[0039] The deodorizing unit 8 purifies the second dried exhaust gas G4 by removing fine particles and odorous gases from the second dried exhaust gas G4. In this embodiment, the deodorizing unit 8 includes a dust collecting unit 81 equipped with a collector such as a dust collector or a cyclone having a dust filter such as a filter cloth to remove fine particles from the second dried exhaust gas G4, and an adsorption unit 80 having an adsorption filter containing activated carbon to remove odorous gases from the second dried exhaust gas G4 by adsorption or the like. The second dried exhaust gas G4 exhausted from the dryer 1 is subjected to dust removal in the dust collecting unit 81, and then further subjected to odorous gas removal in the adsorption unit 80, after which it is released to the outside (atmosphere) as purified gas Ex2. Note that the second dried exhaust gas G4 or purified gas Ex2 is not supplied to the combustion furnace 7, and therefore the temperatures of the combustion furnace 7 and the first dried exhaust gas G2 generated in the combustion furnace 7 are not reduced.

[0040] The deodorizing section 8 may be provided with a secondary air inlet (not shown) that takes in outside air as secondary air from between the dryer 1 and the dust collecting section 81 and mixes it with the second dried exhaust gas G4. By mixing secondary air into the second dried exhaust gas G4, the humidity of the second dried exhaust gas G4 after mixing is reduced, preventing condensation in the dust collecting section 81 and the adsorption section 80. This makes it possible to avoid clogging of the dust removal filter and the adsorption filter.

[0041] (Explanation of drying in the second dryer) The drying gas G3 introduced into the drying tank 10 from the gas inlet 18 is supplied to the sediment layer B from the lower end of the sediment layer B. The drying gas G3 passes through the stationary sediment layer B and comes into solid-gas contact with the granulated material P, thereby drying the granulated material P.

[0042] The second dried exhaust gas G4 containing the moisture of the granulated material P is discharged from the surface of the sediment layer B into the upper space within the drying tank 10. The second dried exhaust gas G4 discharged into the upper space is sent to the deodorizing section 8 via the exhaust section 19. It is preferable that the relative humidity of the second dried exhaust gas G4 discharged into the upper space be in the range of 750% or more and 100% or less, because this allows the material seal described below to function well.

[0043] The sedimentary layer B moves downward while being dried by the drying gas G3, while maintaining its layer state by the discharge of dried granules Pd from the bottom end of the layer by the discharge section 14. At the same time, granulated material P is supplied from the supply section 13 to the surface of the sedimentary layer B. Since the sedimentary layer B receives the drying gas G3 from the bottom end side and new granulated material P is supplied from the top by the supply section 13, the moisture content of the upper layer part of the layer is always high and the moisture content of the lower layer part is low. In other words, the surface of the sedimentary layer B is always covered with a layer of granulated material P with a high moisture content (hereinafter referred to as the seal layer Bs).

[0044] Since the surface of the sedimentary layer B is always covered with the high moisture content material, even if fine particles contained in the sedimentary layer B (for example, fine particles generated when the granulated material P in the lower layer of the sedimentary layer B is dried and powdered) move to the upper layer of the sedimentary layer B with the flow of the drying gas G3, they are captured by the high moisture content granulated material P in the seal layer Bs of the sedimentary layer B (adhering by so-called liquid bridges), preventing dust generation from the sedimentary layer B (so-called material seal). This makes it possible to reduce the amount of fine particles mixed into the second drying exhaust gas G4.

[0045] (carbonization furnace) As shown in FIG. 1 , the carbonization furnace 6 is a device that heats dry granular Pd in ​​a low-oxygen atmosphere to obtain carbide M. The carbonization furnace 6 is, for example, a rotary kiln, a fluidized bed type, or a heat transfer disk or screw type heating device. The carbonization furnace 6 heats and carbonizes the dry granular Pd at a temperature of 250°C to 600°C. After being discharged from the carbonization furnace 6, the carbide M is cooled and aged and shipped as fuel. The carbonization furnace 6 of this embodiment uses a heat transfer disk type device, and the temperature of the heat transfer disk is set to a temperature of 250°C to 600°C. The heat transfer disk is heated by a heat medium such as heated steam, an electric heater, or the like.

[0046] The dry distillation gas F generated by the carbonization process in the carbonization furnace 6 contains combustible gases and odorous components generated from the dried granular Pd. This dry distillation gas F is sent to the combustion furnace 7 and burned together with fuel separately supplied to the combustion furnace 7.

[0047] When carbonizing dried granules Pd in ​​the carbonization furnace 6, if the moisture content of the dried granules Pd is high, thermal energy is consumed by the latent heat of evaporation and the sensible heat of water vapor depending on the amount of moisture contained in the dried granules Pd. In other words, the lower the moisture content of the dried granules Pd, the more energy can be saved because the amount of heat required for the carbonization process (for example, the amount of heat required to heat the heat transfer disk) can be reduced. In this embodiment, the dryer 1 dries the dried granules Pd to a moisture content of 10% or less, thereby reducing the amount of heat required for the carbonization process and saving energy.

[0048] As described above, a carbide processing apparatus and a carbide processing method that achieve energy savings can be provided.

[0049] (Another embodiment) (1) In the above embodiment, the drying processing unit D has a preliminary dryer 3, a storage tank 4, a granulator 5, and a main dryer 1, and the material to be carbonized is transported in the order of the preliminary dryer 3, the storage tank 4, the granulator 5, the main dryer 1, and the carbonization furnace 6. However, the drying processing unit D may not have the storage tank 4 or the granulator 5. The drying processing unit D may also not have the preliminary dryer 3.

[0050] An example of a case where the drying processing section D does not have a granulator 5 is a case where the drying processing section D has a preliminary dryer 3, a storage tank 4, and a main dryer 1, and the material to be carbonized is transported in the order of preliminary dryer 3, main dryer 1, storage tank 4, and carbonization furnace 6.

[0051] Another example of a case where the drying processing section D does not have a storage tank 4 or a granulator 5 is a case where the drying processing section D has a preliminary dryer 3 and a main dryer 1, and the material to be carbonized is transported in the order of the preliminary dryer 3, the main dryer 1, and the carbonization furnace 6.

[0052] In another example where the drying processing unit D does not have a preliminary dryer 3, the drying processing unit D has a main dryer 1 that receives the material to be carbonized that has been pre-dried after being dehydrated in a different facility, and the same effect as the two-stage drying that performs preliminary drying and finish drying described above can be obtained. The material to be carbonized can be transported in the order of the granulator 5, the main dryer 1, the storage tank 4, and the carbonization furnace 6, or the order of the main dryer 1, the storage tank 4, and the carbonization furnace 6, or the order of the main dryer 1 and the carbonization furnace 6. Other examples include the case where the material to be carbonized is transported in the order of the storage tank 4, the granulator 5, the main dryer 1, and the carbonization furnace 6, or the case where the material is transported in the order of the storage tank 4, the main dryer 1, and the carbonization furnace 6, or the case where the material is transported in the order of ....

[0053] (2) In the above embodiment, the deodorizing section 8 purifies the second dried exhaust gas G4 by removing fine particles and odorous gases contained therein, and the deodorizing section 8 is described as including the dust collecting section 81 and the adsorption section 80. The second dried exhaust gas G4 exhausted from the present dryer 1 is subjected to dust removal in the dust collecting section 81, odorous gases are removed in the adsorption section 80, and the gas is then released to the outside (atmosphere). However, in the present dryer 1, the fine particles contained in the second dried exhaust gas G4 are reduced by a material seal, and therefore the deodorizing section 8 may not be provided with the dust collecting section 81.

[0054] (3) In the above embodiment, the deodorizing section 8 purifies the second dried exhaust gas G4 by removing fine particles and odorous gases contained therein, and the deodorizing section 8 includes the dust collecting section 81 and the adsorption section 80. The second dried exhaust gas G4 exhausted from the dryer 1 is subjected to dust removal in the dust collecting section 81, has odorous gases removed in the adsorption section 80, and is then released to the outside (atmosphere). However, instead of removing odorous gases in the deodorizing section 8 (adsorption section 80), the second dried exhaust gas G4 may be sent to the combustion furnace 7 to combustibly decompose and remove the odorous gases. In this case, however, the second dried exhaust gas G4 contains a large amount of water vapor and has a large amount of sensible heat, which may increase the amount of fuel (calorie) required in the combustion furnace 7.

[0055] (4) In the above embodiment, the ventilation unit 17 draws in outside air, heats it to 40°C to 100°C, and supplies it to the drying tank 10 as the drying gas G3. However, the drying gas G3 is not limited to being heated and supplied to the drying tank 10. There is also a case where the ventilation unit 17 draws in outside air (for example, 10°C to 30°C) and supplies it directly to the drying tank 10 as the drying gas G3.

[0056] When the ventilation section 17 draws in outside air and heats it to 40°C or higher, which is higher than the outside air temperature, it may be possible to reduce the volume of the drying tank 10 and make the dryer 1 more compact. Also, by adjusting the temperature of the drying gas G3 and controlling it to a constant temperature, it becomes easy to adjust the moisture content of the dried granules Pd. On the other hand, when the ventilation section 17 draws in outside air and supplies it directly to the drying tank 10 as the drying gas G3, it is possible to simplify the configuration of the dryer 1 and reduce costs.

[0057] The configurations disclosed in the above embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, as long as no contradiction arises. Furthermore, the embodiments disclosed in this specification are examples, and the embodiments of the present invention are not limited to these, and can be modified as appropriate within the scope that does not deviate from the purpose of the present invention.

[0058] The following describes exemplary embodiments of the present invention.

[0059] [1] The present invention can be a carbonized material processing apparatus comprising: a carbonization processing section that carbonizes a material to be carbonized; and a drying processing section that dries the material to be carbonized that is supplied to the carbonization processing section, wherein the drying processing section has a first dryer that pre-dries the material to be carbonized, and a second dryer that finishes drying the material to be carbonized that has been pre-dried in the first dryer in a layered state, and the second dryer has an aeration section that ventilates a drying gas from below the layer of the material to be carbonized, and an exhaust section that supplies the material to be carbonized below the layer of the layer to the carbonization processing section.

[0060] According to the above configuration, the material to be carbonized is pre-dried in a first dryer, and then the pre-dried material is finish-dried in a second dryer. By performing drying in two stages, pre-drying and finish-drying, drying conditions can be adjusted to match the moisture content of the material to be carbonized if the moisture content is high, or to match the moisture content of the material to be carbonized if the moisture content is lower than expected in the pre-drying. This allows the material to be sufficiently dried, reducing the thermal energy required for the carbonization process (realizing energy savings).

[0061] According to the above configuration, the second dryer finishes drying the material to be carbonized while it is piled up in layers, i.e., while it is in a stationary layer state. This prevents the material from moving and colliding with each other due to this movement, resulting in powdering. This prevents problems in the carbonization process caused by powdering and achieves energy savings.

[0062] According to the above configuration, during finish drying, the ventilation section ventilates the drying gas from the bottom of the sedimentary layer of the material to be carbonized (hereinafter simply referred to as the sedimentary layer). This ventilation allows the drying of the carbonized material in the sedimentary layer to proceed from the bottom. That is, the lower layer of the sedimentary layer in the second dryer is kept dry, while the upper layer, including the surface layer, maintains a relatively high moisture content. As a result, in the second dryer, the surface of the sedimentary layer is covered with the material to be carbonized, which has a high moisture content. Therefore, even if fine particles of the material to be carbonized (e.g., fine particles resulting from powdering in the lower layer of the sedimentary layer) migrate to the upper layer of the sedimentary layer accompanied by the flow of drying gas, they are captured by the material to be carbonized in the upper layer of the sedimentary layer, which has a high moisture content (adhering by so-called liquid bridges), thereby preventing dust generation from the sedimentary layer.

[0063] [2] A further characteristic configuration of the carbonized material processing device according to [1] above is that the first dryer is a hot air drying furnace that dries the carbonized material by bringing hot air into contact with it, and the drying gas has a lower temperature than the hot air.

[0064] According to the above configuration, in the first dryer, the material to be carbonized is exposed to hot air having a higher temperature than the drying gas, thereby allowing drying to proceed at a high speed. On the other hand, in the second dryer, the material to be carbonized is dried with a relatively low-temperature drying gas, thereby allowing drying to proceed without the risk of ignition or fire. In more detail, as long as the moisture content of the material to be carbonized is within a range that does not pose a risk of ignition or fire (hereinafter referred to as "ignition, etc."), the first dryer may dry the material at a high speed using high-temperature hot air. On the other hand, if the moisture content of the material to be carbonized has decreased to a level that poses a risk of ignition or fire, low-temperature hot air can be used for drying, allowing drying to proceed while avoiding the risk of ignition, etc.

[0065] [3] A further characteristic configuration of the carbide treatment device according to the above [1] or [2] can be that the temperature of the drying gas is 100°C or less.

[0066] According to the above configuration, even if the moisture content of the material to be carbonized decreases to a level that poses a risk of ignition, etc., drying can be progressed while avoiding the risk of ignition, etc.

[0067] [4] A further characteristic configuration of the carbonized material processing apparatus according to any one of the above [1] to [3] may be that it further comprises a granulator that granulates the carbonized material pre-dried in the first dryer, and the second dryer dries the granulated material granulated in the granulator.

[0068] According to the above configuration, powdering of the material to be carbonized by granulation is prevented, and problems in the carbonization process due to powdering are prevented, thereby realizing energy savings. Furthermore, by preventing powdering, it is possible to increase the ventilation rate of the drying gas in the second dryer, and it is also possible to sufficiently reduce the moisture content of the material to be carbonized (granulated material) before the carbonization process, thereby realizing energy savings.

[0069] [5] A further characteristic configuration of the carbonized material processing device according to any one of [1] to [4] above may be that it further comprises a combustion section that combusts the exhaust gas discharged from the carbonization processing section and the exhaust gas discharged from the first dryer, and a deodorization section that deodorizes the exhaust gas discharged from the second dryer, and the first dryer dries the carbonized material using the combustion exhaust gas from the combustion section as a heat source.

[0070] According to the above configuration, the exhaust gas discharged from the carbonization unit and the first dryer is supplied to the combustion unit, where the odorous gas and flammable gas contained therein are burned and removed. The heat of the exhaust gas generated in the combustion unit is used as a heat source for the first dryer.

[0071] According to the above configuration, the low-temperature exhaust gas discharged from the second dryer is deodorized by removing odorous gases in a deodorizing unit equipped with an activated carbon filter or the like, and then released to the outside. Because the low-temperature exhaust gas discharged from the second dryer is not supplied to the combustion unit, the temperature of the exhaust gas generated in the combustion unit is not lowered by the low-temperature exhaust gas discharged from the second dryer. This makes it possible to reduce the amount of fuel (such as fossil fuel) used for combustion in the combustion unit, thereby achieving energy savings.

[0072] [6] The present invention can be a carbonized material processing method that includes a carbonization step of carbonizing an object to be carbonized, and a drying step of drying the object to be carbonized in the carbonization step, wherein the drying step includes a first drying step of pre-drying the object to be carbonized, and a second drying step of finishing drying the object to be carbonized that has been pre-dried in the first drying step in a layered state, and the second drying step includes an aeration step of ventilating a drying gas from below the deposited layer of the object to be carbonized, and a cutting step of cutting out the object to be carbonized from below the deposited layer.

[0073] [7] Furthermore, a further feature of the carbonized material processing method according to [6] above may be that it further includes a combustion step of combusting the exhaust gas generated in the carbonization processing step and the exhaust gas generated in the first drying step, and a deodorization step of deodorizing the exhaust gas generated in the second drying step.

[0074] According to the above method, it is possible to obtain the same effects as those of the above-mentioned carbide treatment device. [Industrial Applicability]

[0075] The present invention can be applied to a carbide processing apparatus and a carbide processing method. [Explanation of symbols]

[0076] 1: Main dryer (second dryer) 3: Pre-dryer (first dryer, hot air drying oven) 4: Reservoir 5: Granulator 6: Carbonization furnace (carbonization processing section) 7: Combustion furnace (combustion section) 8: Deodorizing section 9: Control section 13: Supply section 14: Discharge section 17: Ventilation section 100: Carbide treatment equipment B: Sedimentary layer D: Drying processing section Ex1: Combustion exhaust gas F: Dry distillation gas (exhaust gas discharged from the carbonization treatment unit) G1: Hot air G2: Primary drying exhaust gas (exhaust gas discharged from the primary dryer) G3: Drying gas G4: Secondary drying exhaust gas (exhaust gas discharged from the secondary dryer) L1: Dehydrated material (material to be carbonized) L2: Pre-dried product (material to be carbonized) M: Carbide P: Granulated material (material to be carbonized) Pd: Dry granules (material to be carbonized)

Claims

1. A drying processing unit that performs finish drying on pre-dried carbonized objects having a moisture content of 5% by weight or more and 25% by weight or less, stacked in layers, to obtain finish-dried carbonized objects; a carbonization processing unit that carbonizes the carbonization object that has been finish-dried in the drying processing unit to produce fuel, The drying processing unit a ventilation section for ventilating a drying gas from below the deposited layer of the material to be carbonized; a discharge section that supplies the material to be carbonized below the sediment layer to the carbonization processing section.

2. The carbonized material processing apparatus according to claim 1 , wherein the drying processing section includes a preliminary dryer for pre-drying the material to be carbonized and a main dryer for performing the finish drying.

3. Further, a combustion unit is provided for combusting the exhaust gas discharged from the carbonization treatment unit, The carbonized material processing apparatus according to claim 2 , wherein the preliminary dryer pre-dries the material to be carbonized using the combustion exhaust gas from the combustion section as a heat source.

4. Further, a deodorizing unit is provided to deodorize the exhaust gas discharged from the drying processing unit. The carbonized material processing apparatus according to claim 3, wherein the combustion section combusts the exhaust gas discharged from the carbonization processing section and the exhaust gas discharged from the preliminary dryer.

5. A drying process step in which pre-dried carbonized objects having a moisture content of 5% by weight or more and 25% by weight or less are stacked in layers and then finish-dried to obtain finish-dried carbonized objects; a carbonization step of carbonizing the carbonization object that has been finish-dried in the drying step to produce fuel, The drying step a ventilation step of ventilating a drying gas from below the deposited layer of the carbonization object; a cutting step of cutting out the object to be carbonized below the sediment layer.

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