JP6878840B2 - Cooling system - Google Patents

Description

The present disclosure relates to a cooling device for cooling hydrous coal dried by heating.

Coal has more than three times the recoverable life of petroleum, and its reserves are not unevenly distributed compared to petroleum. Therefore, coal is expected as a natural resource that can be stably supplied for a long period of time. Coal is classified into peat, lignite, lignite, subbituminous coal, bituminous coal, semi-smokeless coal, and smokeless coal in ascending order of carbon content. Peat, sub-coal, brown coal, and sub-bituminous coal (hereinafter referred to as hydrous coal) have a higher water content (moisture content) than bituminous coal, semi-anthracite coal, and smokeless coal (hereinafter referred to as anthracite coal, etc.).

Of the hydrous coal, lignite is said to account for half of the world's coal reserves, so effective use of lignite is being considered. However, as described above, hydrous coal such as lignite has a higher water content than anthracite coal and the like. Therefore, hydrous coal has a low calorific value per unit weight and low energy efficiency as a fuel for transportation costs.

Therefore, a technique has been developed in which superheated steam is supplied to the hydrated coal to heat and dry the hydrated coal while flowing it (for example, Patent Document 1). Hydrous coal dried by heating (hereinafter, dried hydrous coal is referred to as "dry coal") may ignite when it comes into contact with the atmosphere at a high temperature (for example, about 80 ° C. to 150 ° C.). Therefore, in the technique of Patent Document 1, the dry coal is cooled by supplying a low-temperature inert gas from the bottom surface of the storage tank containing the high-temperature dry coal.

Japanese Unexamined Patent Publication No. 2013-173086

In the technique of Patent Document 1 described above, it is necessary to use a large amount of inert gas for cooling the dry coal. Therefore, there is a problem that the cost required for the inert gas is high.

In view of such a problem, the present disclosure aims to provide a cooling device capable of cooling dry coal at low cost.

In order to solve the above problems, the cooling device according to one aspect of the present disclosure comprises a object to be cooled obtained by heating and drying a hydrous coal and ferromagnetic particles having a temperature lower than that of the object to be cooled. A mixing unit for mixing and exchanging heat, a transport device on which the mixture of the object to be cooled and the ferromagnetic particles generated by the mixing section is placed, and a transport device for transporting the mixture, and on the transport device. said mixture, and a separation unit you separated into該被cooled product and ferromagnetic particles, the separation portion is a disk shape, the center is located at the outside of the conveying device, A main body portion in which a part of a plurality of regions divided in the circumferential direction is provided vertically above the transport device, an electromagnet provided in each of the plurality of regions in the main body portion, and the main body portion. The rotating part that rotates the main body and the electromagnet located vertically above the transporting device are energized so that the center of the rotating shaft is the rotating shaft and the rotating shaft is in the vertical direction. It has a control unit that puts the electromagnet located in a non-energized state into a non-energized state .

Further, a cooling unit for cooling the ferromagnetic particles separated by the separation unit is provided, and the mixing unit mixes the ferromagnetic particles cooled by the cooling unit with the object to be cooled. May be good.

Further, a control unit that controls the amount of the ferromagnetic particles introduced into the mixing unit may be provided so that the object to be cooled separated by the separation unit has a temperature lower than a predetermined temperature.

Further, the ferromagnetic particles may be composed of at least iron.

It is possible to cool dry coal at low cost.

It is a figure explaining the drying system. It is a figure explaining the cooling apparatus. It is a figure explaining an example of a separation part. It is a figure explaining the rotation of a main body part by a drive part, and the power supply control to an electromagnet. It is a figure explaining another example of a separation part.

An embodiment of the present disclosure will be described in detail below with reference to the accompanying drawings. The dimensions, materials, other specific numerical values, etc. shown in such an embodiment are merely examples for facilitating understanding, and do not limit the present disclosure unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are designated by the same reference numerals to omit duplicate description, and elements not directly related to the present disclosure are omitted from the illustration. To do.

(Drying system 100)
FIG. 1 is a diagram illustrating a drying system 100. As shown in FIG. 1, the drying system 100 includes a drying device 110, a cooling device 120, and a storage unit 130, and dries the hydrous coal. Here, lignite will be described as an example of hydrous coal.

The drying device 110 dries the lignite BC by heating the lignite BC. The drying device 110 is, for example, a fluidized bed drying furnace, and includes a storage tank, a fluidized gas supply unit, and a heat transfer tube. The containment tank accommodates lignite BC. The fluidized gas supply unit supplies fluidized gas (for example, water vapor) from the lower part of the fluidized bed (containment tank). The heat transfer tube is arranged in a fluidized bed (containment tank), and a heat medium having a temperature higher than that of lignite BC passes through the heat transfer tube. Since various existing techniques can be applied to the technique for drying lignite BC, detailed description thereof will be omitted here.

The cooling device 120 cools the lignite BC (dry coal DC (object to be cooled)) dried by the drying device 110. The specific configuration of the cooling device 120 will be described in detail later.

The storage unit 130 stores the dry coal DC cooled by the cooling device 120. The dry coal DC stored in the storage unit 130 is supplied to a dry coal utilization facility such as a boiler.

Hereinafter, the cooling device 120 according to the present embodiment will be described in detail.

(Cooling device 120)
FIG. 2 is a diagram illustrating the cooling device 120. As shown in FIG. 2, the cooling device 120 includes a mixing unit 210, a transport device 212, a separation unit 220, a cooling unit 230, a return device 232, a temperature measuring unit 240, and a control unit 250. It is composed. In FIG. 2, the flow of the dry coal DC, the ferromagnetic particle SP, and the mixture MX is indicated by a solid arrow, and the signal flow is indicated by a broken line.

Dry charcoal DC is introduced into the mixing unit 210 from the drying device 110. Further, the ferromagnetic particle SP is introduced into the mixing unit 210 by the return device 232 described later. The mixing unit 210 mixes the dry coal DC and the ferromagnetic particles SP having a temperature lower than that of the dry coal DC (for example, about room temperature (25 ° C.)) for a predetermined time. Here, the predetermined time (contact time) is such that the temperatures of the dry coal DC and the ferromagnetic particles SP are substantially equal to each other due to contact with each other. In the present embodiment, the ferromagnetic particle SP is composed of iron (Fe). That is, the ferromagnetic particle SP is an iron particle.

The mixing unit 210 includes, for example, a housing, a shaft, rotary blades, and a motor. Dry coal DC and ferromagnetic particles SP are introduced into the housing. The shaft is provided in the housing so that the longitudinal direction is along the horizontal direction. The rotary blade has a flat plate shape and is fixed to the shaft. The rotary blades are erected radially from the outer peripheral surface of the shaft. The motor rotates the shaft. Since various existing techniques can be applied to the technique of mixing two kinds of solids such as dry coal DC and ferromagnetic particle SP, detailed description thereof will be omitted here.

Due to the configuration including the mixing unit 210, the dry coal DC (about 80 ° C. to 150 ° C.) and the low-temperature ferromagnetic particles SP are in contact with each other for a predetermined time, and heat exchange is performed between the dry coal DC and the ferromagnetic particles SP. It will be done. That is, heat is transferred from the dry coal DC to the ferromagnetic particles SP, which cools the dry coal DC.

Since the ferromagnetic particle SP is a solid, it has a larger heat capacity than a gas. Therefore, the dry coal DC can be cooled with an extremely small amount of ferromagnetic particles SP as compared with the conventional technique of cooling with an inert gas. Further, in the conventional technique of cooling only with the inert gas, the cost for recovering and circulating the inert gas is high. On the other hand, since the cooling device 120 of the present embodiment recovers or circulates a smaller amount of the ferromagnetic particles SP than the inert gas, the cost required for recovery and circulation can be reduced. Therefore, the dry coal DC can be cooled efficiently and at low cost.

As described above, the mixture MX (for example, about 50 ° C.) of the dry coal DC generated by the mixing unit 210 and the cooled ferromagnetic particles SP is transferred to the separating unit 220 by the transport device 212 (for example, a conveyor). Be transported.

The separation unit 220 separates the mixture MX produced by the mixing unit 210 into the dry coal DC and the ferromagnetic particles SP. In the present embodiment, the separation unit 220 includes a magnet.

FIG. 3 is a diagram illustrating an example of the separation unit 220, and is a top view of the separation unit 220. In FIG. 3, the rotation direction of the main body 310 is indicated by a solid arrow, and the flow of the mixture MX and the dry coal DC is indicated by a white arrow.

As shown in FIG. 3, the separation unit 220 includes a main body unit 310 and a drive unit 320. The main body 310 has a disk shape and is installed above the transport device 212 so that the in-plane direction is horizontal. Further, one or a plurality of electromagnets are provided in each of the regions 314A, 314B, and 314C divided into three in the circumferential direction in the main body 310. In the present embodiment, the main body 310 is arranged so that the center is located outside the transport device 212, and a part (at least one region) of the main body 310 is vertically above the transport device 212. It is located so that the other portion of the main body 310 is located vertically above the cooling 230.

The drive unit 320 rotates the main body 310 so that the center of the main body 310 is the rotation shaft 312 and the rotation shaft 312 is along the vertical direction. Further, the drive unit 320 controls the supply of electric power to the electromagnet.

FIG. 4 is a diagram illustrating rotation of the main body 310 by the drive unit 320 and control of power supply to the electromagnet. In FIG. 4, the rotation direction of the main body 310 is indicated by a solid arrow, the flow of the mixture MX and the dry coal DC is indicated by a white arrow, the energized state of the electromagnet is indicated by a black fill, and the electromagnet is not. The energized state is indicated by a white fill. Further, in order to facilitate understanding, the description of the drive unit 320 is omitted in FIG.

As shown in FIG. 4A, at time t1, the drive unit 320 energizes the electromagnet arranged in the region 314B located vertically above the transport device 212. Then, the ferromagnetic particles SP in the mixture MX conveyed by the transfer device 212 are attracted by the electromagnet (adsorbed to the electromagnet) in the process of passing vertically below the region 314B, and are separated from the mixture MX. Become. Then, the dry coal DC obtained as a result of separating the ferromagnetic particles SP from the mixture MX is transported to the storage unit 130 in the subsequent stage by the transport device 212.

Then, when the electromagnet in the region 314B approaches the allowable amount capable of adsorbing the ferromagnetic particles SP (time t2), as shown in FIG. 4 (b), the drive unit 320 energizes the electromagnet in the region 314A from the non-energized state. The state is switched and the main body 310 is rotated 120 degrees (here, counterclockwise). Further, the drive unit 320 switches the electromagnet in the region 314B from the energized state to the non-energized state. That is, the drive unit 320 energizes the electromagnet located vertically above the transport device 212, and energizes the electromagnet retracted from the transport device 212. Then, the ferromagnetic particles SP in the mixture MX conveyed by the transfer device 212 are attracted by the electromagnet and separated from the mixture MX in the process of passing vertically below the region 314A.

Further, at time t2, the electromagnet in the region 314B is switched from the energized state to the non-energized state by the drive unit 320. Therefore, at time t1, the ferromagnetic particles SP adsorbed on the electromagnet in the region 314B are transferred to the cooling unit 230. It falls and is temporarily stored in the cooling unit 230. That is, the ferromagnetic particles SP are removed (adsorption is released) from the electromagnet in the region 314B.

Similarly, when the electromagnet in the region 314A approaches the allowable amount capable of adsorbing the ferromagnetic particles SP (time t3), as shown in FIG. 4C, the drive unit 320 removes the electromagnet in the region 314C from the non-energized state. It switches to the energized state and rotates the main body 310 by 120 degrees. Further, the drive unit 320 switches the electromagnet in the region 314A from the energized state to the non-energized state.

In this way, the drive unit 320 energizes the electromagnet located vertically above the transfer device 212, so that the ferromagnetic particles SP can be separated from the mixture MX conveyed by the transfer device 212. Further, the drive unit 320 can remove the ferromagnetic particles SP from the electromagnet (regenerate the electromagnet) by deenergizing the electromagnet retracted from the transport device 212.

Further, the drive unit 320 rotates the main body 310 to energize the electromagnet located vertically above the transport device 212 and de-energize the electromagnet retracted from the transport device 212, whereby the ferromagnetic particle SP It is possible to continuously perform the separation of the electromagnet and the regeneration of the electromagnet in parallel.

In this way, the dry coal DC separated by the separation unit 220 is introduced into the storage unit 130 by the transport device 212 and stored in the storage unit 130. On the other hand, the ferromagnetic particles SP separated by the separation unit 220 (electromagnet) and stored in the cooling unit 230 are cooled by the cooling unit 230.

The cooling unit 230 is composed of, for example, an air cooling device, and cools the ferromagnetic particles SP separated by the separation unit 220. The return device 232 is composed of, for example, a conveyor, and introduces the cooled ferromagnetic particle SP into the mixing unit 210 based on a control command by the control unit 250 described later.

The ferromagnetic particle SP can be reused by the configuration including the cooling unit 230 and the return device 232. Therefore, it is possible to further cool the dry coal DC at low cost.

The temperature measuring unit 240 measures the temperature of the dry coal DC introduced into the mixing unit 210, that is, the temperature of the dry coal DC discharged from the drying device 110. Further, the temperature measuring unit 240 measures the temperature of the dry coal DC separated by the separating unit 220.

The control unit 250 is composed of a semiconductor integrated circuit including a CPU (Central Processing Unit). The control unit 250 reads a program, parameters, and the like for operating the CPU itself from the ROM, and manages and controls the entire cooling device 120 in cooperation with the RAM as a work area and other electronic circuits.

In the present embodiment, the control unit 250 controls the return device 232 based on the temperature of the dry coal DC measured by the temperature measurement unit 240. Specifically, the control unit 250 describes the temperature of the dry coal DC introduced into the mixing unit 210, the amount of the dry coal DC introduced into the mixing unit 210, and the residence time (contact time) of the dry coal DC in the mixing unit 210. ), The dry coal DC separated by the separation unit 220 is predetermined based on the temperature of the ferromagnetic particle SP introduced into the mixing unit 210 (the temperature of the ferromagnetic particle SP cooled by the cooling unit 230). The amount of the ferromagnetic particle SP to be introduced into the mixing unit 210 is derived so as to be lower than the specified temperature (for example, the ignition temperature). Then, the control unit 250 controls the return device 232 so that the derived amount of the ferromagnetic particle SP is introduced into the mixing unit 210.

With the configuration including the control unit 250, the dry coal DC separated by the separation unit 220 can be maintained at a temperature lower than the temperature desired by the user. For example, assume that the control unit 250 derives the amount of ferromagnetic particles SP to be introduced into the mixing unit 210 so that the dry coal DC separated by the separation unit 220 becomes lower than the ignition temperature. In this case, it is possible to avoid a situation in which the dry coal DC separated by the separation unit 220 (the dry coal DC conveyed by the transfer device 212 and the dry coal DC stored in the storage unit 130) ignites. ..

As described above, according to the cooling device 120 according to the present embodiment, the dry coal DC is lowered by a simple configuration in which the ferromagnetic particles SP having a temperature lower than that of the dry coal DC and the dry coal DC are simply mixed. It is possible to cool at a cost. Further, by forming the cooling medium for cooling the dry coal DC with a ferromagnet (ferromagnetic particle SP), it can be easily separated by a magnet. Further, by forming the ferromagnetic particles SP with iron, it is possible to reduce the cost of the cooling medium itself. Further, since the ferromagnetic particles SP can be recycled, the cost can be further reduced.

Although the embodiments have been described above with reference to the accompanying drawings, it goes without saying that the present disclosure is not limited to such embodiments. It is clear that a person skilled in the art can come up with various modifications or modifications within the scope of the claims, and it is understood that they also naturally belong to the technical scope.

For example, in the above embodiment, the case where the ferromagnetic particle SP is an iron particle has been described as an example. As a result, the ferromagnetic particle SP itself can be manufactured at low cost. However, the ferromagnetic particle SP may be composed of at least iron (for example, an iron alloy or the like). Further, the ferromagnet particles SP are not limited to iron, and may be composed of ferromagnets such as cobalt (Co) and nickel (Ni). Further, the ferromagnet particle SP may be composed of a ferromagnet and copper (Cu). For example, it may be a ferromagnet particle SP in which a ferromagnet is coated with copper. As a result, the separation portion 220 can be composed of a magnet, so that separation becomes easy. Further, by coating with copper having a relatively large thermal conductivity, the dry coal DC can be cooled more efficiently.

Further, in the above embodiment, the case where the separation unit 220 is configured to include an electromagnet has been described as an example. However, the separation unit 220 may be configured to include a permanent magnet. Various existing techniques can be applied to the technique for separating the ferromagnetic particles SP using a magnet.

FIG. 5 is a diagram illustrating another example of the separation unit 420, and is a top view of the separation unit 420. In FIG. 5, the moving direction of the main body 510 is indicated by a solid arrow, the flow of the mixture MX and the dry coal DC is indicated by a white arrow, the energized state of the electromagnet is indicated by a black fill, and the electromagnet is not. The energized state is indicated by a white fill.

As shown in FIG. 5, the separation unit 420 includes a main body unit 510 and a drive unit 520. The main body 510 has a rectangular shape and is installed above the transport device 212 so that the in-plane direction is horizontal. A drive unit 520 is connected to one end of the main body 510 in the lateral direction.

One or more electromagnets are provided in each of the regions 514A and 514B divided into two in the longitudinal direction in the main body 510. The main body 510 is arranged so that the longitudinal direction intersects the transport direction of the transport device 212, and a part (at least one region) of the main body 510 is located vertically above the transport device 212. The other part of the part 510 is arranged so as to be located vertically above the cooling part 230a or the cooling part 230b. The cooling units 230a and 230b are arranged on both sides of the transport device 212.

The drive unit 520 moves the main body 510 in the longitudinal direction. Further, the drive unit 520 controls the supply of electric power to the electromagnet.

As shown in FIG. 5, at time t4, the drive unit 520 energizes the electromagnet arranged in the region 514A located vertically above the transfer device 212. Then, the ferromagnetic particles SP in the mixture MX conveyed by the transfer device 212 are attracted by the electromagnet and separated from the mixture MX in the process of passing vertically below the region 514A. Then, the dry coal DC obtained as a result of separating the ferromagnetic particles SP from the mixture MX is transported to the storage unit 130 in the subsequent stage by the transport device 212.

Then, when the electromagnet in the region 514A approaches the allowable amount capable of adsorbing the ferromagnetic particles SP (time t5), the drive unit 520 moves the main body 510 after switching the region 514B from the non-energized state to the energized state. , Region 514B is positioned vertically above the transport device 212. After that, the drive unit 520 switches the region 514A from the energized state to the non-energized state. Then, the ferromagnetic particles SP in the mixture MX conveyed by the transfer device 212 are attracted by the electromagnet and separated from the mixture MX in the process of passing vertically below the region 514B.

Further, at time t5, the electromagnet in the region 514A is switched from the energized state to the non-energized state by the drive unit 520, so that the ferromagnetic particles SP adsorbed on the electromagnet in the region 514A are transferred to the cooling unit 230b at time t4. It falls and is temporarily stored in the cooling unit 230b. That is, the ferromagnetic particles SP are removed from the electromagnet in the region 514A.

Similarly, when the electromagnet in the region 514B approaches the allowable amount capable of adsorbing the ferromagnetic particles SP (time t6), the drive unit 520 moves the main body 510 after switching the region 514A from the non-energized state to the energized state. The region 514A is positioned vertically above the transfer device 212. After that, the drive unit 520 switches the region 514B from the energized state to the non-energized state.

Further, in the above embodiment, the air cooling device has been described as an example of the cooling unit 230. However, the structure of the cooling unit 230 is not limited as long as it can cool the ferromagnetic particles SP. For example, the cooling unit 230 may be composed of a water cooling device, a device for cooling with another refrigerant, or a Peltier element.

Further, as the hydrous coal, lignite was taken as an example for explanation. However, the hydrous coal may be peat, lignite, or subbituminous coal, or may be a mixture of any two or more of peat, lignite, lignite, and subbituminous coal.

The present disclosure can be used in a cooling device for cooling hydrous coal dried by heating.

120 Cooling device 210 Mixing unit 220 Separation unit 230 Cooling unit 250 Control unit

Claims (4)

A mixing portion in which a material to be cooled obtained by heating and drying hydrous coal and ferromagnetic particles having a temperature lower than that of the material to be cooled are mixed and heat exchanged.
A transport device on which a mixture of the object to be cooled and the ferromagnetic particles generated by the mixing unit is placed and the mixture is conveyed,
The mixture on the conveyor device, a separation unit you separated into該被cooled product and ferromagnetic particles,
Equipped with a,
The separation part
A main body portion having a disk shape, the center of which is located outside the transport device, and a part of a plurality of regions divided in the circumferential direction provided vertically above the transport device.
An electromagnet provided for each of the plurality of regions in the main body,
A rotating portion that rotates the main body portion so that the center of the main body portion serves as a rotation axis and the rotation axis is in the vertical direction.
A control unit that energizes the electromagnet located vertically above the transport device and de-energizes the electromagnet located outside the transport device.
Cooling device with. A cooling unit for cooling the ferromagnetic particles separated by the separation unit is provided.
The cooling device according to claim 1, wherein the mixing unit is a mixture of the ferromagnetic particles cooled by the cooling unit and the object to be cooled. Claim 1 or 2 provided with a control unit that controls the amount of the ferromagnetic particles introduced into the mixing unit so that the object to be cooled separated by the separation unit has a temperature lower than a predetermined temperature. The cooling device described in. The cooling device according to any one of claims 1 to 3, wherein the ferromagnetic particles are composed of at least iron.

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