Storage tank

Abstract

To provide a storage tank capable of preventing accumulation and residence of carbides to pipings and sensors projecting to an internal space of a storage tank.SOLUTION: A storage tank 3 for accepting carbides M and conducting carbide treatments is assembled with a tank body 30 having a feed port 31 for feeding carbides M from an upper part and an exhaust port 32 for exhaustion of carbides M from a lower part, and a rod-like member composed of a piping 34 having projection parts 34a, Ta projecting to an internal space 30A from a side wall of the tank body 30 for circulating a gas or a liquid or a sensor T, wherein the rod-like member has an accumulation residence prevention structure for prevention of accumulation and residence of carbides M to the projection parts 34a, Ta.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a reservoir. [Background technology]

[0002] Organic waste such as sewage sludge is carbonized, for example, by heating, and reused as fuel. The carbonized organic waste obtained in this way has highly active surface functional groups on its particle surface immediately after carbonization, and is known to have self-heating properties in its original state. Therefore, to ensure safety during storage, the carbonized organic waste is subjected to a process to reduce its self-heating properties in a storage tank (a so-called aging process, hereinafter sometimes simply referred to as "carbonization process") (see, for example, Patent Document 1).

[0003] Patent document 1 describes a carbide treatment device that has a temperature sensor that measures the temperature inside the storage tank in order to appropriately control the temperature of the carbide in the storage tank, and a supply rate adjustment unit that adjusts the supply rate of the treatment gas supplied to the storage tank based on the temperature detected by the temperature sensor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-12061 Summary of the Invention [Problem to be solved by the invention]

[0005] The temperature sensor described in Patent Document 1 protrudes from the side wall of the storage tank toward the internal space of the storage tank. Therefore, carbide supplied to the storage tank may accumulate on the protruding portion, and the carbide may remain in the storage tank for a longer period than the set period. Because carbide has a self-heating property, if carbide remains on the temperature sensor for a longer period than the set period, the temperature may become higher than expected. Furthermore, there is a possibility that the temperature sensor may be subjected to fatigue failure due to the protruding portion being heated for a long period by the accumulated carbide.

[0006] Therefore, there is a need for a storage tank that can prevent charcoal from accumulating and remaining on the piping and sensors that protrude into the internal space of the storage tank. [Means for solving the problem]

[0007] The characteristic configuration of the storage tank according to the present invention is that it is a storage tank that receives carbonized material and performs carbonized material processing, and comprises a tank body having an inlet for introducing the carbonized material from the top and an outlet for discharging the carbonized material from the bottom, and a rod-shaped member that has a protrusion that protrudes from the side wall of the tank body toward the internal space and is composed of a pipe through which gas or liquid flows, or a sensor, and the rod-shaped member has a deposition and retention prevention structure that prevents the carbonized material from accumulating and retaining on the protrusion.

[0008] According to this configuration, the rod-shaped member formed by the pipe or sensor has a deposition and retention prevention structure that prevents carbide from accumulating and remaining on the protruding portion that protrudes from the side wall of the storage tank toward the internal space, thereby preventing carbide from accumulating and remaining on the protruding portion. This prevents carbide from remaining in the storage tank for longer than a set period of time, making it possible to prevent the carbide from becoming hotter than expected. Furthermore, because carbide does not accumulate or remain on the protruding portion, there is no need to require excessive heat resistance for the protruding portion, allowing for a wider range of materials to be used for the protruding portion.

[0009] Another characteristic feature is that the deposition stagnation prevention structure is a cover member that covers the upper part of the protrusion, and the cover member overlaps with the protrusion in a planar view, and is formed over the entire length of the protrusion with a top portion provided above the protrusion and two inclined portions that slope in different directions from the top portion toward the tangent direction of the protrusion.

[0010] According to this configuration, because the cover member covers the top of the protrusion, the carbide introduced through the inlet comes into contact with the cover member, not the protrusion. Furthermore, because the cover member has a top and an inclined portion, the carbide moves downward along the inclination of the inclined portion due to its own weight, and does not accumulate on the cover member. Therefore, the carbide does not remain in the storage tank for longer than the set period, which prevents the carbide from becoming hotter than expected and also prevents the cover member from becoming hotter than expected.

[0011] Another characteristic feature is that a part of the inclined portion abuts against the protruding portion.

[0012] According to this configuration, a portion of the inclined portion abuts against the protruding portion, so that carbides that move along the inclined portion do not accumulate on the protruding portion, thereby reducing contact between the carbides and the protruding portion.

[0013] Another characteristic feature is that the carbide is not present in the space surrounded by the cover member and the protrusion.

[0014] According to this configuration, the space surrounded by the cover member and the protruding portion is free of carbides, so even if carbides accumulate in the storage tank and cover the protruding portion and the cover member, the carbides will not enter the space, thereby preventing the accumulation and retention of carbides in the protruding portion.

[0015] Another characteristic feature is that a space surrounded by the cover member and the protrusion is filled with a filler material.

[0016] According to this configuration, the space surrounded by the cover member and the protruding portion is filled with the filler, so even if carbide accumulates in the storage tank and covers the protruding portion and the cover member, the carbide will not enter the space, thereby preventing the accumulation and retention of carbide in the protruding portion.

[0017] Another characteristic feature is that the upper surface of the cover member includes a coating layer that reduces the adhesion of the carbide.

[0018] According to this configuration, the upper surface of the cover member includes a coating layer that reduces the adhesion of carbides, so that carbides are less likely to adhere to the cover member and carbides that come into contact with the cover member tend to slide down the slope, thereby preventing carbides from accumulating and remaining on the cover member. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a configuration diagram of an organic sludge recycling system. [Figure 2] FIG. [Figure 3] FIG. 10 is a perspective view of a protruding portion of a pipe protruding into the internal space of the storage tank. [Figure 4] FIG. 4 is a cross-sectional view of a protruding portion of a pipe. [Figure 5] FIG. 10 is a cross-sectional view of a protruding portion of a pipe according to another embodiment. [Figure 6] FIG. 10 is a cross-sectional view of a protruding portion of a pipe according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of a storage tank according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiment, and various modifications are possible without departing from the spirit of the present invention.

[0021] [Overall structure] As shown in Fig. 1, a storage tank 3 according to the present invention is used for carbonization treatment in an organic sludge recycling system 200 that uses organic sludge, such as sewage sludge, as recycled fuel F. The storage tank 3 is disposed in a carbonization treatment device 100 included in the organic sludge recycling system 200. In this embodiment, a case will be described in which dried sludge L, which is organic sludge that has been dried and granulated in advance, is supplied to the organic sludge recycling system 200. The organic sludge recycling system 200 obtains recycled fuel F by carbonizing the dried sludge L, for example.

[0022] The carbonized material treatment device 100 receives the carbonized material M obtained from the dried sludge L and performs a process to reduce the self-heating property of the carbonized material M (so-called aging process (low-temperature oxidation process), hereinafter referred to as "carbonized material treatment").

[0023] The organic sludge recycling system 200 mainly includes a carbonization furnace 10, a cooler 20, and a stock tank 27 in addition to the carbonized material treatment device 100.

[0024] The dried sludge L is granulated into cylindrical pellets, for example, by extrusion granulation. This is to homogenize the particle shape, bulk density, and other particle properties of the dried sludge L or the charcoal M and recycled fuel F obtained from the dried sludge L, thereby improving the handleability of the charcoal M and the like and the uniformity of the charcoal treatment in the organic sludge recycling system 200 and the charcoal treatment device 100. The dried sludge L may be granulated into other shapes, such as spherical, or may not be granulated.

[0025] The dried sludge L is supplied to the carbonization furnace 10 and carbonized. This produces cylindrical pellet-shaped carbonized material M. The carbonized material M discharged from the carbonization furnace 10 is humidified and cooled in a cooler 20. It is then stored in the carbonized material processing device 100 for a predetermined time. The carbonized material processing device 100 performs carbonization treatment by passing a treatment gas G containing oxygen (an example of an oxygen-containing gas) through the stored carbonized material M for a predetermined time (see also Figure 2). The carbonized material M becomes recycled fuel F that can be safely stored in a tank, etc., and is discharged from the carbonized material processing device 100. The recycled fuel F discharged from the carbonized material processing device 100 is stored in a stock tank 27 in preparation for shipment to the market. Hereinafter, the downstream side of the transport path of the carbonized material M or recycled fuel F from the carbonization furnace 10 to the stock tank 27 will be simply referred to as the downstream side, and the opposite side will be referred to as the upstream side.

[0026] [Carbonization furnace] The carbonization furnace 10 is a device that heats dried sludge L in a low-oxygen atmosphere (hereinafter, this may be referred to as "carbonization treatment") to obtain a carbonized material M. The carbonization furnace 10 is composed of a rotary kiln. The carbonization furnace 10 may be of a rotary kiln type, a fluidized bed type, a screw type, or the like. The carbonization furnace 10 carbonizes the dried sludge L at a temperature of approximately 250°C to 600°C.

[0027] In this embodiment, during carbonization treatment in the carbonization furnace 10, combustible pyrolysis gas is generated from the dried sludge L. The pyrolysis gas is supplied to, for example, a secondary combustion furnace 12 and burned, and then passed through exhaust gas treatment equipment 13, such as an exhaust heat recovery machine or a scrubber, and discharged to the outside as combustion exhaust Ef. After being discharged from the carbonization furnace 10, the carbonized material M is introduced into a cooler 20 via a chute 11 or the like.

[0028] [Cooler] The cooler 20 is a device that cools the carbide M. In this embodiment, the cooler 20 is a device that is equipped with a nozzle 20E that supplies cooling water CW to a screw conveying device that moves the carbide M using a screw provided in a casing. In this embodiment, the cooler 20 conveys the carbide M in one direction using a screw, and sprays and supplies cooling water CW to the carbide M being conveyed.

[0029] The carbide M inside the cooler 20 is cooled by the latent heat of vaporization of the cooling water CW. In this embodiment, the carbide M is rapidly cooled to below 60°C. In this embodiment, the carbide M is cooled and humidified by spraying and supplying the cooling water CW. In this embodiment, the carbide M is humidified to a moisture content of 5% to 20%, and particularly preferably 13% to 17%, on a dry basis (weight ratio to the weight of completely dried carbide). In addition, a jacket through which a refrigerant flows may be provided on the outside of the cooler 20, and a method of indirectly cooling the carbide M inside the cooler 20 may also be used.

[0030] In this embodiment, a cooling gas CG, which is an inert gas such as nitrogen, flows through the cooler 20 in a direction opposite to the flow of the carbide M. In the cooler 20, in addition to the cooling gas CG and the water vapor of the cooling water CW, flammable gases such as carbon monoxide gas and odorous gases are generated. Therefore, the exhaust gas from the cooler 20 is introduced into the secondary combustion furnace 12 via an exhaust pipe 14. The cooled carbide M is supplied from the cooler 20 to a flight conveyor 22. In this embodiment, the carbide M is supplied to the flight conveyor 22 via a rotary valve 21 that separates the cooler 20 from an inlet (not shown) of the flight conveyor 22.

[0031] The carbide M discharged from the cooler 20 is transported to the cushion tank 23 by the flight conveyor 22, and is supplied from the cushion tank 23 to the carbide processing device 100. In this embodiment, the carbide M transported to the cushion tank 23 is supplied to the carbide processing device 100, for example, via a rotary valve (not shown) or piping. Note that instead of using the flight conveyor 22, the carbide M discharged from the cooler 20 may be supplied to the carbide processing device 100 via a chute or the like. Furthermore, instead of transporting by the flight conveyor 22, transport may be performed using pneumatic transport, a belt conveyor, a bucket conveyor, or the like.

[0032] [Carbide Treatment Apparatus] The carbide processing device 100 processes carbide M to obtain recycled fuel F. The recycled fuel F obtained in the carbide processing device 100 is transported to a cushion tank 26 by a flight conveyor 25. At this time, an air cooling device 25a, such as a heat exchanger supplied with a refrigerant from a chiller, is disposed upstream of the flight conveyor 25, and the recycled fuel F may be cooled using air A cooled by the air cooling device 25a. The recycled fuel F is transferred from the cushion tank 26 to a stock tank 27 and stored until shipment. Note that the cushion tank 26 may be omitted and the recycled fuel F may be directly transferred to the stock tank 27 via a chute or the like, or it may be transported using a pneumatic transport, a belt conveyor, a bucket conveyor, or the like instead of transporting by the flight conveyor 25. Furthermore, the cushion tank 26 and the stock tank 27 may be omitted, and the transported recycled fuel F may be directly supplied to a user facility.

[0033] As shown in FIG. 2 , the carbide processing apparatus 100 includes a storage tank 3 for storing carbide M and performing carbide processing, and an aeration unit 4 for ventilating (supplying) a processing gas G to a deposit B of carbide M stored in the storage tank 3. The carbide processing apparatus 100 also includes an in-tank thermometer for measuring the internal temperature of the storage tank 3. The internal temperature of the storage tank 3 refers to the measured temperature of the deposit B. In addition to the in-tank thermometer, the carbide processing apparatus 100 may also include a gas thermometer for measuring the gas temperature of the processing gas G supplied to the storage tank 3, a gas flow meter for measuring the gas flow rate of the processing gas G supplied to the storage tank 3, or an instrument for measuring the temperature of the carbide M before it is introduced into the storage tank 3 (temperature before introduction). The in-tank thermometer is configured using a known temperature sensor, and therefore detailed description thereof will be omitted.

[0034] As shown in FIG. 1 , the processing gas G is a gas containing at least a first processing gas G1 containing oxygen, such as air A. The ventilation unit 4 in this embodiment supplies the processing gas G, which is a mixture of the first processing gas G1 and the second processing gas G2. The second processing gas G2 is a gas containing an inert gas (e.g., nitrogen). The oxygen concentration of the processing gas G is determined by the mixing ratio of the first processing gas G1 and the second processing gas G2. Therefore, the oxygen concentration of the processing gas G decreases as the mixing ratio of the second processing gas G2 increases. The ventilation unit 4 includes a first fan 41 for supplying the first processing gas G1 and a second fan 42 for supplying the second processing gas G2. The second fan 42 for supplying the second processing gas G2 may be omitted and a constant amount of the second processing gas G2 may be supplied, or the supply amount may be adjusted using a valve or the like instead of the second fan 42.

[0035] The carbide processing device 100 performs a storage process of storing the carbide M in a storage tank 3, an aeration process of passing a processing gas G containing oxygen through a deposit B of the carbide M, and a discharge process of retaining the carbide M for a predetermined period of time and then discharging it, thereby achieving carbide processing of the carbide M and obtaining recycled fuel F.

[0036] [Storage tank] As shown in Fig. 2, the storage tank 3 is a metal container that stores the carbide M in layers by piling it up vertically (from bottom to top). The storage tank 3 is also a supply container that supplies the carbide M stored in layers to the next process while maintaining the layered state. The storage tank 3 has an inlet 31 for introducing the carbide M into the internal space 30A of the tank body 30 of the storage tank 3, an outlet 32 ​​for discharging the recycled fuel F from the internal space 30A of the storage tank 3, and an emergency outlet 35 that can discharge the carbide M in an emergency.

[0037] The tank body 30 of the storage tank 3 in this embodiment has a circular cross section that narrows at the bottom, and the narrowing angle (cone angle) of the bottom is set so that the residence time of the carbide M (recycled fuel F) discharged from the discharge port 32 is uniform within the tank. Note that a pincushion-shaped baffle (a so-called cone baffle) may be provided near the boundary between the upper and lower parts of the storage tank 3 and near the center of the storage tank 3 in the radial direction, to make the residence time of the carbide M (recycled fuel F) within the tank uniform.

[0038] The storage tank 3 has an inlet 31 at the upper end of the tank body 30. The inlet 31 includes a supply pipe connected to the internal space 30A of the storage tank 3, and may include a rotary valve provided on the supply pipe. When the inlet 31 includes a rotary valve, the carbide M can be introduced into the internal space 30A of the storage tank 3 while being isolated from the atmosphere upstream. In this embodiment, the carbide M is continuously supplied to the inlet 31 at a constant supply rate.

[0039] The storage tank 3 has a discharge port 32 at the lower end of the tank body 30. The discharge port 32 has a discharge pipe 32b connected to the internal space 30A of the storage tank 3, and a rotary valve 32a provided in the discharge pipe 32b as a discharge device for discharging the carbide M (recycled fuel F).

[0040] Discharge pipe 32b is a cylindrical pipe that extends downward from the lower end of tank body 30. Storage tank 3 can discharge recycled fuel F from internal space 30A of storage tank 3 to the bottom of storage tank 3 while being isolated from the atmosphere downstream by rotary valve 32a. Recycled fuel F is continuously discharged from discharge port 32.

[0041] The carbide M is continuously fed into this storage tank 3 at a constant supply rate, and the recycled fuel F is continuously discharged from the storage tank 3. The average residence time of the carbide M (recycled fuel F) in the storage tank 3 is controlled to be, for example, 2 to 4 days (48 to 96 hours). The residence time is set to a length necessary and sufficient for obtaining the recycled fuel F from the carbide M. If the residence time is too short, the self-heating property of the carbide M cannot be sufficiently reduced, and the safety of the recycled fuel F cannot be guaranteed. If the residence time is too long, the production efficiency of the recycled fuel F decreases, which is uneconomical and therefore undesirable.

[0042] The storage tank 3 has a plurality of (twelve in this embodiment) pipes 34 (an example of rod-shaped members) on its sidewall that introduce the processing gas G into the internal space 30A and supply the oxygen-containing processing gas G to the deposits B. In this embodiment, the pipes 34 may be provided at a plurality of locations along the vertical direction of the sidewall of the storage tank 3, and may be connected to the sidewall at the upper, middle, or lower part of the storage tank 3. The pipes 34 are attached along the radial direction of the tank body 30, penetrating the wall of the tank body 30 from the outer side of the storage tank 3, with their ends positioned inside the tank. Therefore, the pipes 34 have protrusions 34a that protrude from the sidewall of the storage tank 3 toward the internal space 30A. The insertion depths of the plurality of pipes 34 into the internal space 30A of the storage tank 3 may be different or the same.

[0043] The processing gas G supplied from the pipe 34 is uniformly passed through the particle layer of the sediment B from the bottom to the top of the storage tank 3. The processing gas G comes into solid-gas contact with the particle surfaces of the carbide M while passing through the particle layer of the sediment B, and oxidizes surface functional groups and the like on the particle surfaces. Note that the pipe 34 connected to the side wall at the bottom of the storage tank 3 may be connected to the bottom wall of the storage tank 3.

[0044] Note that a pipe may be provided on the side wall of the storage tank 3 to supply an inert gas such as nitrogen or a liquid such as a cooling fluid to the internal space 30A of the storage tank 3. As with the pipe 34, these pipes may also be attached to the tank body 30 so that their ends are positioned in the internal space 30A of the storage tank 3.

[0045] The deposits B in the storage tank 3 form multiple layer regions made up of particle layers. The processing gas G that has passed through the particle layers of the deposits B is discharged to the outside as exhaust gas E from an exhaust pipe 33 provided at the upper end of the storage tank 3. The exhaust gas E is introduced into a secondary combustion furnace 12 (see FIG. 1) or the like, purified, and then discharged into the atmosphere.

[0046] A plurality of (three in this embodiment) temperature sensors T (rod-shaped members, an example of sensors) that are sensor probes of in-tank thermometers are attached to the storage tank 3. The temperature sensor T in this embodiment is a rod-shaped sensor probe with a temperature detection element at its tip, and uses a resistance temperature detector. Note that the temperature sensor T may also be a thermocouple or other sensor.

[0047] The temperature sensor T is installed on the side wall of the storage tank 3. The temperature sensor T is attached along the radial direction of the tank body 30 such that a rod-shaped sensor probe penetrates from the outer side surface of the storage tank 3 into the wall of the tank body 30 and the tip of the sensor is positioned inside the tank of the storage tank 3. Therefore, the temperature sensor T has a protrusion Ta that protrudes from the side wall of the storage tank 3 toward the internal space 30A. Note that the temperature sensor T is not limited to being attached along the radial direction of the tank body 30, and may be attached so as to be inclined upward or downward with respect to the vertical direction of the tank body 30, or so as to be inclined with respect to the radial direction of the tank body 30.

[0048] The multiple temperature sensors T may be inserted to different or the same depth into the internal space 30A of the storage tank 3. If the tip of one temperature sensor T is located near the center of the sediment B and the tips of the other temperature sensors T are located near the outer periphery of the sediment B, the internal temperature of the sediment B can be measured accurately.

[0049] [Deposition prevention structure] Because carbide M is introduced into the storage tank 3 through an inlet 31 provided at the top, carbide M is likely to accumulate on the protruding portion Ta of the temperature sensor T, which protrudes from the side wall of the storage tank 3 toward the internal space 30A, and on the protruding portion 34a of the piping 34. Because carbide M has self-heating properties, if carbide M remains on the protruding portions Ta, 34a for a long period of time, the carbide M may reach a temperature higher than expected. In addition, there is a risk that these may be subjected to fatigue failure due to being heated for a long period of time by the carbide M accumulated on the protruding portions Ta, 34a. Therefore, the temperature sensor T and the piping 34 have an accumulation and retention prevention structure to prevent carbide M from accumulating and remaining on the protruding portions Ta, 34a.

[0050] As shown in FIGS. 2 to 4, the sedimentation and retention prevention structure is a cover member 5 that covers the upper part of the protrusion Ta, 34a. The cover member 5 has a top 51 and a pair of inclined portions 52, 52, and the top 51 and inclined portions 52 cover the upper part of the protrusion Ta, 34a over the entire length of the protrusion Ta, 34a. One end of the cover member 5 is connected to the side of the tank body 30. As shown in FIG. 4, the top 51 is provided above the protrusion Ta, 34a and overlaps with the protrusion Ta, 34a in a plan view of the protrusion Ta, 34a (viewed from above). In other words, the top 51 is not in contact with the protrusion Ta, 34a. The top 51 may have an angular mountain shape that is convex upward, or may have a smoothly curved surface that bulges upward.

[0051] The pair of inclined portions 52, 52 are inclined in different directions from the apex 51 toward the tangential direction of the protrusion Ta, 34a. The inclination refers to being inclined with respect to a horizontal plane. The tangential direction includes not only the direction defined by the apex 51 and the contact point P of the inclined portion 52 and the protrusion Ta, 34a, but also the direction defined by the apex 51 and a point near the contact point P. Therefore, the inclined portion 52 does not have to be in contact with the protrusion Ta, 34a. The length from the apex 51 to the tip of the inclined portion 52 is not particularly limited; the tip may be located at the same position as the contact point P or may extend downward from the contact point P along the inclined direction. The apex 51 and the inclined portion 52 may be integrally formed of metal or resin.

[0052] In this embodiment, as shown in FIG. 4, the top 51 is disposed on a vertical plane having the central axis of the protrusion Ta, 34a. That is, the pair of inclined portions 52, 52 are disposed symmetrically with respect to the vertical plane. The distance between the top 51 and the protrusion Ta, 34a can be determined arbitrarily. However, if the distance is too short, the inclination angle θ of the inclined portion 52 relative to the vertical plane becomes small, and carbides M accumulate without sliding on the protrusion Ta, 34a. Furthermore, if the distance is too long, the inclination angle θ of the inclined portion 52 becomes large. However, the dimensions of the inclined portion 52 become large, and therefore the insertion opening formed on the outer periphery of the tank body 30 when attaching the piping 34 with the cover member 5 or the temperature sensor T to the tank body 30 becomes large. Therefore, it is preferable to determine the distance between the top 51 and the protrusion Ta, 34a so that the inclination angle θ of the inclined portion 52 is equal to or smaller than the angle of repose of the deposit B. Specifically, the inclination angle θ of the inclined portion 52 is preferably 45° or less, more preferably 30° or less, and even more preferably 15° or less.

[0053] In this embodiment, the inclined portion 52 abuts against the protrusion Ta, 34a at the contact point P, so that the carbide M introduced from the introduction port 31 is unlikely to enter the space 5A surrounded by the cover member 5 and the protrusion Ta, 34a. Furthermore, the inclined portion 52 extends in the inclined direction downward from the contact point P. On the other hand, when the carbide M is introduced into the storage tank 3 and the carbide M accumulates up to the top of the storage tank 3, the protrusion Ta, 34a may be covered with the deposit B. In this case, since the carbide M is likely to enter between the extending portion of the cover member 5 and the protrusion Ta, 34a, it is preferable that the tip of the inclined portion 52 is provided near the contact point P.

[0054] 3, a partition wall 53 is disposed between the end of the cover member 5 facing the internal space 30A and the end of the protrusion Ta, 34a. The partition wall 53 separates the internal space 30A from the space 5A surrounded by the cover member 5 and the protrusion Ta, 34a. The partition wall 53 has a surface perpendicular to the protrusion direction of the protrusion Ta, 34a and is provided on the same plane as the ends of the cover member 5 and the protrusion Ta, 34a. This prevents communication between the internal space 30A and the space 5A surrounded by the cover member 5 and the protrusion Ta, 34a. This prevents carbides M from entering the space 5A, thereby preventing the accumulation of carbides M on the upper surfaces of the protrusion Ta, 34a.

[0055] The space 5A surrounded by the cover member 5 and the protrusions Ta, 34a may be filled with a filler. The filler may be, for example, a heat-resistant ceramic. Even if a portion of the cover member 5 is damaged, the filler prevents contact between the carbide M and the protrusions Ta, 34a, thereby preventing the carbide M from accumulating on the protrusions Ta, 34a. The filler and the cover member 5 may be integrally formed. That is, the cross section of the cover member 5 may be formed into a substantially triangular prism shape so as not to have the space 5A.

[0056] A coating layer may be formed on the surface of the cover member 5, i.e., the surfaces of the top portion 51 and the inclined portion 52, so that the carbide M can slide easily along the inclination direction. The coating layer may be of any type as long as it makes it easier for the carbide M to slide off the surface of the cover member 5, and may be, for example, a coating of fluorine or the like. This reduces the adhesion between the cover member 5 and the carbide M, making it easier for the carbide M to slide off from the cover member 5, thereby preventing the carbide M from accumulating and remaining on the protrusions Ta, 34a.

[0057] Other Embodiments (a) In the above embodiment, the inclined portions 52, 52 are arranged symmetrically with respect to the vertical plane of the protrusion Ta, 34a, but the inclined portions 52, 52 do not have to be arranged symmetrically with respect to the vertical plane, and as shown in Figure 5, the inclination angle of one inclined portion 52 may be different from the inclination angle of the other inclined portion 52.

[0058] (b) In the above embodiment, the protrusion Ta of the temperature sensor T and the protrusion 34a of the piping 34 are exemplified as protrusions, but a water piping that supplies water or the like to the tank body 30 of the storage tank 3 may protrude into the internal space 30A, and a cover member 5 may be placed on the protrusion of such a water piping.

[0059] (c) In the above embodiment, the protrusion Ta, 34a protrudes from the side wall of the tank body 30 toward the internal space 30A. However, it may protrude from the bottom wall of the tank body 30 toward the internal space 30A. In this case, as shown in FIG. 6, a cover member 5 may be provided to cover the upper end of the protrusion Ta, 34a. In the embodiment of (c), the cover member 5 may be conical, and the lower end of the cover member 5 and the protrusion Ta, 34a are not in contact. Furthermore, the bottom surface of the lower end of the cover member 5 when viewed in the axial direction of the protrusion Ta, 34a may be larger than the tube diameter of the protrusion Ta, 34a. This allows the cover member 5 to cover the protrusion Ta, 34a while still allowing the upper end surface of the protrusion Ta, 34a to communicate with the internal space 30A. This allows gas to be introduced into the tank body 30, temperature measurement, and the like, while preventing the accumulation of carbides M.

[0060] (d) In the above embodiment, the reservoir 3 is provided with the pipe 34 and the temperature sensor T having a structure for preventing accumulation of sediment. However, these may also be disposed in the stock tank 27. [Industrial Applicability]

[0061] The present invention can be used for a storage tank that can prevent carbonized matter from accumulating and remaining on piping and sensors that protrude into the internal space of the storage tank. [Explanation of symbols]

[0062] 3: Reservoir 5: Cover material 5A: Space 30: Tank body 30A: Internal space 31: Inlet 32: Outlet 34: Piping (rod-shaped member) 34a:Protrusion 51:Top 52: Inclined part M: Carbide T: Temperature sensor (rod-shaped component) Ta:Protrusion

Claims

1. A storage tank for receiving carbonized material and performing carbonized material processing, a tank body having an inlet for introducing the carbonized material from an upper portion thereof and an outlet for discharging the carbonized material from a lower portion thereof; a rod-shaped member having a protrusion protruding from the side wall of the tank body toward the internal space, the rod-shaped member being a pipe through which a gas or a liquid flows, or a sensor; The rod-shaped member has a deposition and retention prevention structure that prevents the carbide from depositing and accumulating on the protruding portion.

2. the deposition and retention prevention structure is a cover member that covers an upper portion of the protrusion, The cover member is a top portion that overlaps with the protruding portion in a plan view and is provided above the protruding portion; 2. The storage tank according to claim 1, wherein two inclined portions inclined in different directions from each other are formed along the entire length of the protrusion from the top toward the tangent direction of the protrusion.

3. The storage tank according to claim 2 , wherein a portion of the inclined portion abuts against the protrusion.

4. The storage tank according to claim 3 , wherein the space surrounded by the cover member and the protrusion is configured so that the carbide is not present.

5. The storage tank according to claim 3 , wherein a space surrounded by the cover member and the protrusion is filled with a filler material.

6. The storage tank according to any one of claims 2 to 5, wherein the upper surface of the cover member includes a coating layer that reduces adhesion of the carbide.

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