WO2016084509A1

WO2016084509A1 - Drying system

Info

Publication number: WO2016084509A1
Application number: PCT/JP2015/079169
Authority: WO
Inventors: 石井　徹
Original assignee: 株式会社Ihi
Priority date: 2014-11-26
Filing date: 2015-10-15
Publication date: 2016-06-02
Also published as: JP6520076B2; AU2015351701B2; AU2015351701A1; JP2016099099A

Abstract

The present invention is provided with: a plurality of solar heat collectors (2) that heat a heat transfer medium (X) with solar heat; and a drying furnace (5) that dries an object to be dried (Y) by exchanging heat between the object to be dried (Y) and the heat transfer medium (X) that has been heated by the solar collectors (2).

Description

Drying system

The present disclosure relates to a drying system.
Priority is claimed on Japanese Patent Application No. 2014-238922, filed Nov. 26, 2014, the content of which is incorporated herein by reference.

Conventionally, solid fuels containing a large amount of water such as lignite, biomass and palm scum are badly ignited and combustible due to the effect of the contained water if used as they are, and are dried by sun drying or the like. However, sun drying requires a large space for mounting the fuel, and it is difficult to control the temperature of the fuel during drying. For this reason, in addition to heating by solar radiation, in addition to oxidation and deterioration by exposure to air, heat generated by oxidation is added to the heat of solar radiation, and the temperature may rise abnormally to lead to spontaneous ignition.

On the other hand, it is conceivable to create hot air artificially and use this hot air to dry the fuel. However, the generation of such hot air needs to consume a large amount of fuel and also emits a large amount of carbon dioxide. For this reason, for example, it is conceivable to perform drying without consuming fuel by heating the fuel with heat obtained by condensing the sunlight by applying the gasification facility shown in Patent Document 1 .

Japanese Patent Application Laid-Open No. 2001-123183

However, in the gasification facility disclosed in Patent Document 1, the fuel is directly heated to approximately 1000 ° C. because the condensed sunlight is directly irradiated to the fuel. Such a temperature is not a problem at all in the case of a gasification facility that gasifies fuel, but becomes too high to dry the fuel.

Further, in the gasification facility disclosed in Patent Document 1, in order to heat the fuel to about 1000 ° C., sunlight collected by a plurality of heliostats is collected on a reflection mirror supported upward by a large tower. Furthermore, it is guided to the gasification furnace. For this reason, many heliostats, a large tower, etc. are needed, and an installation enlarges. Moreover, in order to condense the sunlight collected from many heliostats installed in a wide area in a limited range, complicated control is needed, and the subject that equipment cost is increased occurs. In the drying system for drying the fuel, since it is not necessary to heat the temperature of the fuel to about 1000 ° C., it is not necessary to install a large facility as shown in Patent Document 1, and it is desirable to miniaturize the facility.

The present disclosure has been made in view of the above-described problems, and in a drying system for drying a material to be dried, the consumption of fuel used for drying is suppressed by using solar heat, and the facility is enlarged. An object of the present invention is to make it possible to control the temperature of a material to be dried to a temperature suitable for drying and suppressing.

The present disclosure adopts the following configuration as means for solving the above problems.

The first aspect of the drying system of the present disclosure heats a heat transfer medium with solar heat and exchanges heat between a plurality of solar collectors and a heat transfer medium heated by the solar collector and the material to be dried. And a drying oven for drying the material to be dried.

According to the present disclosure, a configuration including a plurality of solar heat collectors that heat the heat transfer medium is employed.
Therefore, by installing a number of solar collectors that can collect the energy required to dry the material to be dried, it is possible to dry the material to be dried, and a huge tower and reflection mirror are installed. Drying without using solar heat can be performed. In addition, since the amount of heat required for drying can be reduced as compared to the amount of heat required to gasify a solid fuel such as coal, in the present disclosure, a large number of heliostats are used as in the above-mentioned gasification facility. Not only does it not have to be installed, it also does not require a complex control system that focuses to a limited area from a widely installed heliostat. Therefore, according to the present disclosure, it is possible to prevent an increase in size of equipment and a complication of control system. Furthermore, according to the present disclosure, the heat of the heat transfer medium is heated by the solar heat and the dry matter is heated by the heat transfer medium, instead of directly heating the material to be dried by the solar heat collected by the solar collector. The configuration is adopted. For this reason, the temperature of the material to be dried can be easily adjusted by adjusting the physical properties (for example, saturated vapor temperature) of the heat transfer medium, the flow velocity of the heat transfer medium at the time of heat exchange, and the like. Therefore, according to the present disclosure, it is possible to adjust the temperature of the material to be dried to a temperature suitable for drying.

It is a flow figure showing a schematic structure of a drying system in a 1st embodiment of this indication. It is a schematic diagram which shows schematic structure of the solar collector with which the drying system in 1st Embodiment of this indication is provided. It is a schematic diagram which shows schematic structure of the solar collector with which the drying system in 1st Embodiment of this indication is provided. In the drying system in a 1st embodiment of the present disclosure, it is an explanatory view in the case of operating an auxiliary boiler only before and behind sunrise time. In the drying system in a 1st embodiment of the present disclosure, it is an explanatory view in the case of operating an auxiliary boiler only before and behind sunset time. In the drying system in a 1st embodiment of the present disclosure, it is an explanatory view in the case of making an auxiliary boiler operate before and behind sunrise time and before and after sunset time. It is a flowchart which shows schematic structure of the drying system in 2nd Embodiment of this indication. The drying system in 2nd Embodiment of this indication WHEREIN: It is explanatory drawing in the case of operating an auxiliary boiler only before and behind sunrise time. In the drying system in a 2nd embodiment of this indication, it is an explanatory view in the case of operating an auxiliary boiler only before and behind sunset time. In the drying system in a 2nd embodiment of the present disclosure, it is an explanatory view in the case of making an auxiliary boiler operate before and behind sunrise time and before and after sunset time. It is a flow figure showing a schematic structure of a drying system in a 3rd embodiment of this indication.

Hereinafter, an embodiment of a drying system according to the present disclosure will be described with reference to the drawings. In the following drawings, the scale of each member is appropriately changed in order to make each member have a recognizable size.

First Embodiment
FIG. 1 is a flow diagram showing a schematic configuration of the drying system 1 of the present embodiment. As shown in this figure, the drying system 1 of the present embodiment includes a plurality of solar collectors 2, a steam drum 3, an auxiliary boiler 4, a drying furnace 5, and a fluidizing gas supply device 6 A supply unit, an inert gas supply unit, a heat transfer medium circulation unit 7, and a control device 8 are provided.

2A and 2B are schematic views showing a schematic configuration of the solar heat collector 2, FIG. 2A is a perspective view, and FIG. 2B is a cross-sectional view. As shown in these drawings, the solar heat collector 2 includes a first reflection plate 2a, a second reflection plate 2b, a heat transfer tube 2c, and a drive device 2d.

The first reflecting plate 2a is a substantially semi-cylindrical reflecting plate whose inner surface serving as a reflecting surface is directed to the upper sky, and reflects sunlight so as to condense on the second reflecting plate 2b. The second reflection plate 2b is supported by the support portion 2e fixed to the first reflection plate 2a, and is a substantially semi-cylindrical reflection plate whose inner surface serving as a reflection surface is directed to the first reflection plate 2a. The heat transfer tube 2c is a straight pipe disposed at the light collecting position of the second reflection plate 2b, and the heat transfer medium X flows inside. The heat transfer tube 2c is fixed by a support mechanism provided outside so as to pass through a through hole provided in the support portion 2e. The driving device 2d supports the first reflecting plate 2a and the second reflecting plate 2b so as to be movable around the heat transfer tube 2c. For example, under the control of the control device 8, the reflecting surface of the first reflecting plate 2a The first reflecting plate 2a and the second reflecting plate 2b are moved so as to face. The second reflection plate 2b improves the light collection efficiency, and also heats the surface of the heat transfer tube 2c on the back side as viewed from the first reflection plate 2a to obtain an effect of improving the heat collection. It is also possible to omit it.

In this solar heat collector 2, the sunlight reflected by the first reflection plate 2a and the second reflection plate 2b is collected at the heat transfer tube 2c, and the heat of the heat obtained by this condenses the heat transfer medium X inside the heat transfer tube 2c. It is heated. In the present embodiment, water is used as the heat transfer medium X, and the heat transfer medium X heated in the solar collector 2 is heated to a degree that some or all of the heat transfer medium X is vaporized. The heat transfer medium X is not limited to water, and, for example, an organic solvent, an inorganic salt, or a metal can also be used. For example, in the case of using an organic solvent, alcohols, fats and oils having a relatively high boiling point and being liquid at normal temperature can be used. Moreover, when using an inorganic salt or a metal, what becomes a liquid at comparatively low temperature is selected in order to ensure fluidity.

As shown in FIG. 1, a plurality of solar heat collectors 2 for heating the heat transfer medium X by such solar heat are provided, and each is connected to the steam drum 3 via a collecting pipe 2f. The number of installed solar collectors 2 is determined based on the amount of steam required to dry the object Y in the drying furnace 5. For example, in the daytime in fine weather, the number of installed solar collectors 2 is determined such that the amount of steam generated by the operating solar collector 2 exceeds the amount of steam required by the drying furnace 5 .

The steam drum 3 is a container for temporarily storing the heat transfer medium X which is partially or totally vaporized by being heated by the solar collector 2, and the steam drum 3 is configured of the solar collector 2 and the drying furnace 5. It is arranged between. The upper portion of the steam drum 3 is connected to the drying furnace 5, and the lower portion is connected to the heat transfer medium circulation portion 7. When the heat transfer medium X is supplied to such a steam drum 3, the heat transfer medium X in a steam state is accumulated in the upper part of the steam drum 3 and is sent out to the drying furnace 5. Further, the heat transfer medium X in a liquid state is collected at the bottom of the steam drum 3 and is sent out to the heat transfer medium circulating unit 7.

The auxiliary boiler 4 is a general-purpose boiler that can be easily started and stopped, for example, and is connected to the steam drum 3. The auxiliary boiler 4 supplementarily heats the heat transfer medium X to generate steam when the amount of steam generation in the solar collector 2 decreases near sunrise time, sunset time, etc. The steam drum 3 is supplied. In the present embodiment, the auxiliary boiler 4 is connected to the control device 8 and generates steam under the control of the control device 8.

The drying furnace 5 includes a chamber 5a, a dividing wall 5b dividing the inside of the chamber 5a into a plurality of regions in the horizontal direction, and a heat transfer pipe 5c inserted into the inside of the chamber 5a. The chamber 5a is a container in which the material to be dried Y is stored. In the chamber 5a, when the material to be dried Y is supplied from the outside, a part of the material to be dried Y previously stored is pushed out and discharged. A plurality of dividing walls 5b are erected at the bottom of the chamber 5a, and a plurality of dividing walls 5b are provided such that the wall surfaces face each other. As the dividing wall 5b, there are provided a first dividing wall 5b1 having an opening at the lower part, and a second dividing wall 5b2 having no opening and having a height smaller than that of the first dividing wall 5b1. They are alternately arranged in the chamber 5a. As the inside of the chamber 5a is divided by the plurality of dividing walls 5b, the object to be dried Y advances while meandering up and down in the chamber 5a as shown by the arrows in FIG. The heat transfer tube 5 c has an inlet end connected to the steam drum 3 and an outlet end connected to the heat transfer medium circulating unit 7. A heat transfer medium X, which exchanges heat with the material to be dried Y in the chamber 5a, flows through the heat transfer tube 5c.
In the drying furnace 5, the material to be dried Y is exchanged by heat exchange between the material to be dried Y flowing with the fluidizing gas Z supplied from the fluidizing gas supply device 6 and the heat transfer medium X flowing through the heat transfer tube 5c. dry.

The to-be-dried material Y dried by such a drying furnace 5 is a solid fuel used as fuels, such as a pulverized coal boiler not shown, and contains much moisture (for example, water content is 20% or more). As such to-be-dried material Y, it is powdered lignite and biomass, for example. In addition to the material to be dried Y, a fluid medium such as sand may be stored inside the chamber 5a in order to enhance the fluidity in the chamber 5a. The fluid medium is separated from the material to be dried Y after being discharged from the chamber 5a, and returned again into the chamber 5a.

The fluidizing gas supply device 6 includes a circulation pipe 6a, an inert gas generator 6b, a blower 6c, a heat exchanger 6d, and a cooler 6e. The circulation pipe 6a is a pipe that is branched at one end to be connected to the bottom of the chamber 5a and connected at the other end to the ceiling of the chamber 5a and serves as a flow path for the fluidizing gas Z. Note that one end side of the circulation pipe 6a is connected to the bottom of the chamber 5a such that each branch end is connected to each region of the chamber 5a divided by the dividing wall 5b. The inert gas generator 6 b generates nitrogen gas (inert gas) used as fluid gas from, for example, the atmosphere, and is connected to the circulation pipe 6 a. The blower 6c is provided at an intermediate position of the circulation pipe 6a, and pumps the fluidizing gas Z. The blower 6c pumps the fluidizing gas Z toward one end side (a side connected to the bottom of the chamber 5a) of the circulation pipe 6a so that the fluidizing gas Z is supplied upward from the bottom of the chamber 5a. Do. Thus, the fluidizing gas Z is supplied from the one end side (the side connected to the bottom of the chamber 5a) of the circulation pipe 6a into the chamber 5a, and the other end side of the circulation pipe 6a (the ceiling portion of the chamber 5a) The fluidization gas Z inside the chamber 5a is recovered from the side).

The heat exchanger 6d is disposed in the middle of the circulation pipe 6a and downstream of the blower 6c. The heat exchanger 6 d exchanges heat between a heat transfer medium X flowing through a return flow pipe 7 a (described later) included in the heat transfer medium circulating unit 7 and the fluidizing gas Z flowing through the circulation pipe 6 a. In the heat exchanger 6d, the heat transfer medium X and the fluidizing gas Z exchange heat, so that the fluidizing gas Z is heated before being supplied to the drying furnace 5, and the fluidizing gas Z causes the chamber 5a to be heated. It is possible to prevent the temperature inside from falling.

The cooler 6e is disposed in the middle of the circulation pipe 6a and on the upstream side of the blower 6c. The cooler 6e cools the fluidizing gas Z in order to condense and separate the water contained in the fluidizing gas Z heated by passing through the inside of the chamber 5a. As a result, the fluidizing gas Z that has been dried is supplied to the blower 6c and the like, and the occurrence of condensation in the blower 6c and the like can be prevented.

As the fluidization gas Z is supplied upward from the bottom of the chamber 5a by the fluidization gas supply device 6 as described above, the material to be dried Y stored in the chamber 5a flows. Thereby, heat exchange between the material to be dried Y and the heat transfer medium X is promoted, and the material to be dried Y can be dried in a short time.

The heat transfer medium circulating unit 7 includes a return flow piping 7a, a condenser 7b, a water supply pump 7c, a water supply preheater 7d, and a steam drum connection piping 7e. The return flow piping 7 a is a piping that connects the drying furnace 5 and the solar heat collector 2 and returns the heat transfer medium X discharged from the drying furnace 5 back to the solar heat collector 2 again. As shown in FIG. 1, the return flow pipe 7a passes through the heat exchanger 6d, whereby the heat transfer medium X flowing through the return flow pipe 7a and the fluidizing gas Z flowing through the circulation pipe 6a are thermal The amount of heat of the heat transfer medium X is transferred to the fluidizing gas Z.

The condenser 7b is disposed in the middle of the return pipe 7a and downstream of the heat exchanger 6d, and cools and liquefies the heat transfer medium X, which is a vapor, by heat exchange with the atmosphere, for example. The feed water pump 7c is disposed further downstream of the condenser 7b, and pumps the heat transfer medium X liquefied by the condenser 7b toward the solar collector 2. The feed water preheater 7d is disposed further downstream of the feed pump 7c, and exchanges heat between the heat transfer medium X discharged from the feed pump 7c and the heat transfer medium X on the upstream side of the condenser 7b. , Preheat the heat transfer medium X supplied to the solar collector 2. The steam drum connection pipe 7 e is a pipe that connects the bottom of the steam drum 3 and the return flow pipe 7 a, and condenses the heat transfer medium X of the liquid accumulated at the bottom of the steam drum 3 without passing through the drying furnace 5. It guides to the upper stream side of vessel 7b. A port (not shown) for additionally supplying the heat transfer medium X to the return flow pipe 7a is provided on the upstream side of the water supply pump 7c. For example, the port may be used to compensate for the decrease in the heat transfer medium X The heat transfer medium X is additionally supplied to the return flow pipe 7a.

The control device 8 controls the entire drying system 1 of the present embodiment, and controls, for example, the auxiliary boiler 4, the inert gas generator 6b, the blower 6c, and the water supply pump 7c. In the drying system 1 of the present embodiment, the operation period of the auxiliary boiler 4 is defined under the control of the control device 8 as described above. For example, under the control of the control device 8, the auxiliary boiler 4 is operated only before and after sunrise time, is operated only before and after sunset time, and is operated before and after sunrise time and before and after sunset time. Moreover, although omitted in FIG. 1, in the drying system 1 of the present embodiment, a valve is provided at a suitable position. The flow rates of the heat transfer medium X and the fluidizing gas Z are adjusted by adjusting the opening degree of these valves by control of the control device 8 or the like.

Then, operation of drying system 1 of this embodiment constituted in this way is explained. In the following description of the operation, the material to be dried Y is continuously supplied in a constant amount to the chamber 5 a of the drying furnace 5.

When sunlight is collected by the first reflection plate 2a and the second reflection plate 2b of the solar collector 2 and the heat transfer medium X flowing through the heat transfer tube 5c is heated by solar heat, a part of the heat transfer medium X is steam To form the heat transfer medium X in the gas-liquid mixed state. The heat transfer medium X generated by the plurality of solar collectors 2 is collected by the collecting pipe 2 f and supplied to the steam drum 3. The heat transfer medium X is separated into gas and liquid in the steam drum 3, and the heat transfer medium X for steam is supplied to the heat transfer tube 5 c of the drying furnace 5. On the other hand, the liquid heat transfer medium X is supplied from the steam drum connection pipe 7 e to the heat transfer medium circulating unit 7 and is supplied again to the solar heat collector 2.

Further, in the fluidizing gas supply device 6, the fluidizing gas Z (inert gas) is supplied from the inert gas generator 6b to the circulation piping 6a, and the blower 6c is driven to fluidize the circulation piping 6a. The gas Z is pumped toward the drying furnace 5. The fluidizing gas Z supplied to the drying furnace 5 is preheated in the heat exchanger 6d, and then supplied from the bottom of the chamber 5a to the inside of the chamber 5a. The material to be dried Y in the chamber 5a is fluidized by supplying the fluidization gas Z from the bottom of the chamber 5a. The fluidizing gas Z in the chamber 5a is recovered from the upper portion of the chamber 5a to the circulation pipe 6a, water is removed by the cooler 6e, and then pressure-fed again by the blower 6c.

As described above, when the heat transfer medium X supplied to the heat transfer tube 5c inserted into the chamber 5a is supplied, the heat transfer medium X inside the heat transfer tube 5c and the material to be dried Y outside the heat transfer tube 5c The object to be dried Y is heated by heat exchange. As a result, the moisture contained in the material to be dried Y evaporates, and the material to be dried Y is dried. The dried material to be dried Y is discharged to the outside of the chamber 5a by being pushed by the new material to be dried Y supplied to the chamber 5a continuously. The water evaporated from the material to be dried Y is recovered along with the fluidizing gas Z in the circulation pipe 6a.

The heat transfer medium X discharged to the outside of the chamber 5 a through the heat transfer tube 5 c flows into the return flow pipe 7 a of the heat transfer medium circulating unit 7. The heat transfer medium X flowing into the return flow pipe 7a passes through the heat exchanger 6d, passes through the feed water preheater 7d, and is returned to liquid by being cooled by the condenser 7b. The heat transfer medium X that has become liquid is pumped toward the solar collector 2 by the water supply pump 7c. The heat transfer medium X pumped by the feed water pump 7 c is preheated in the feed water preheater 7 d and then supplied to the solar collector 2 again.

Further, the auxiliary boiler 4 is operated only before and after the sunrise time, only before and after the sunset time, or before and after the sunrise time and before and after the sunset time. When the auxiliary boiler 4 is operated, steam (heat transfer medium X) is generated and supplied to the steam drum 3. The steam thus supplied from the auxiliary boiler 4 to the steam drum 3 is mixed with the steam (heat transfer medium X) supplied from the solar collector 2 to the steam drum 3 and used.

Subsequently, an example of an operation pattern using the auxiliary boiler 4 of the drying system 1 of the present embodiment will be described with reference to FIGS. 3 to 5.

FIG. 3 is an explanatory view of the case where the auxiliary boiler 4 is operated only before and after the sunrise time in the drying system 1 of the present embodiment. Moreover, FIG. 4 is explanatory drawing in the case where the auxiliary | assistant boiler 4 is operated only before and behind sunset time in the drying system 1 of this embodiment. FIG. 5 is an explanatory view of the case where the auxiliary boiler 4 is operated before and after the sunrise time and before and after the sunset time in the drying system 1 of the present embodiment. In these figures, a graph showing the relationship between the time and the temperature of the heat transfer medium X in the steam drum 3 is shown at the top, but in this graph, the relationship between the time and energy obtained from the sun is shown for reference. The graph shown is superimposed and shown.

As shown in FIG. 3, when the auxiliary boiler 4 is operated before and after the sunrise time, the operation of the auxiliary boiler 4 is started before the sunrise. Since the heat transfer medium X can not be heated by the solar collector 2 at the time before sunrise, even if steam is supplied to the steam drum 3 from the auxiliary boiler 4 supplementarily, the solar collector 2 side The temperature of the heat transfer medium X supplied to the steam drum 3 via the collecting pipe 2f is low, and the temperature of the heat transfer medium X in the entire steam drum 3 does not reach the boiling point.

The drying system 1 of the present embodiment performs the preheating operation until the temperature of the heat transfer medium X in the steam drum 3 reaches the boiling point. This preheating operation is an operation performed in a state in which the material to be dried Y is not supplied to the drying furnace 5, and is an operation in which the temperature of the heat transfer medium X is gradually raised toward the boiling point. The preheating operation is performed either in a state in which the material to be dried Y is not stored in the drying furnace 5 or in a state in which the material to be dried Y whose drying is not completed on the previous day is stored in the drying furnace 5. In such a preheating operation, the heat transfer medium X is gradually heated by the operation of the auxiliary boiler 4 (including heating by the solar collector 2 after sunrise). Further, in the preheating operation, the fluidizing gas Z is supplied to the drying furnace 5 by the fluidizing gas supply device 6. Accordingly, the fluidizing gas Z is also heated as the heat transfer medium X is heated, and it is possible to prevent the material to be dried Y from being cooled by the fluidizing gas Z after the start of the drying operation.

At sunrise time, although the energy obtained from the sun is lower compared to after noon, the heat transfer medium X is heated by the solar collector 2 and the temperature of the heat transfer medium X in the steam drum 3 rises sharply to the boiling point . When the temperature of the heat transfer medium X in the steam drum 3 reaches the boiling point, the auxiliary boiler 4 is stopped, the material to be dried Y is put into the drying furnace 5, and the drying operation to dry the material to be dried Y is performed. Then, when the sunset time approaches and the energy obtained from the sun decreases, the temperature of the heat transfer medium X falls below the boiling point, so at this point the supply of the material to be dried Y to the drying furnace is stopped and the drying operation is stopped. Do.

After that, the cooling operation is performed until the sunset time. In this cooling operation, for example, by directing the solar collector 2 in a direction different from that of the sun, the heat transfer medium X is not heated by the solar collector 2, and the drying furnace 5 by the fluidizing gas supply device 6 is Continue to supply the fluidization gas Z. By this, the to-be-dried material Y is stirred without being heated, and the temperature inside the drying furnace 5 is rapidly lowered. Then, after the temperature inside the drying furnace 5 is cooled to a temperature at which there is no risk of spontaneous ignition or the like, the cooling operation is ended, and the drying system 1 of the present embodiment is stopped until the operation restarts the next day.

In the case where the auxiliary boiler 4 is not operated before and after the sunrise time, the heat transfer medium X is heated by the solar collector 2 after the sunrise, so as indicated by the dashed dotted line in FIG. The time for the heat transfer medium X to reach the boiling point is delayed. Therefore, by operating the auxiliary boiler 4 before and after the sunrise time, it is possible to advance the start timing of the drying operable period, and it is possible to dry the object to be dried Y in a longer period.

Further, as shown in FIG. 4, when the auxiliary boiler 4 is operated before and after the sunset time, the operation of the auxiliary boiler 4 is started before the sunset. As sunset approaches, the energy obtained from the sun decreases, so the energy for heating the heat transfer medium X in the solar collector 2 decreases, and the temperature of the heat transfer medium X is maintained at the boiling point only with the solar collector 2 It can not be done. However, the temperature of the heat transfer medium X does not immediately decrease to normal temperature as sunset approaches and further passes after sunset time, but gradually decreases (see FIG. 3). Here, as shown in FIG. 4, when the auxiliary boiler 4 is operated before and after the sunset time, new steam is supplied from the auxiliary boiler 4 to the steam drum 3 so that it is before and after the sunset time. The decrease in the temperature of the heat transfer medium X can be suppressed. Therefore, the temperature of the heat transfer medium X can be maintained at the boiling point for a while even after the sunset time, and the drying of the material to be dried Y can be continued. In this way, by operating the auxiliary boiler 4 before and after the sunset time, it is possible to extend the drying operable period to after the sunset time as shown in FIG. It is possible to dry the

Also, as described above, the temperature of the heat transfer medium X can not be maintained at the boiling point by the solar collector 2 alone before and after sunset time, but the heat transfer medium X is warmed by the daytime operation There is. Therefore, the input energy for maintaining the temperature of the heat transfer medium X at the boiling point by using the auxiliary boiler 4 can be reduced compared to the case where the auxiliary boiler 4 is operated before and after sunrise.
Therefore, when the auxiliary boiler 4 is operated before and after the sunset time, it is possible to extend the dry operation possible period with a smaller amount of fuel before and after sunrise, than when operating the auxiliary boiler 4.

Further, as shown in FIG. 5, when the auxiliary boiler 4 is operated before and after the sunrise time and before and after the sunset time, the start timing of the drying operation possible period is advanced, and the drying operation possible period is sunset. It is possible to extend until after the time. In such a case, more fuel is required as compared to the case where the auxiliary boiler 4 is operated only before and after the sunrise time and the case where the auxiliary boiler 4 is operated only before and after the sunset time, but the longest The drying operable period can be secured. For this reason, for example, the operation time of the factory where the drying system 1 of the present embodiment is installed is long, and it is a useful operation pattern when it is desired to operate the drying system 1 for a long time according to the operation time.

According to the drying system 1 of the present embodiment as described above, a configuration including a plurality of solar heat collectors 2 for heating the heat transfer medium X is employed. Therefore, by installing a number of solar collectors capable of collecting the energy necessary to dry the material to be dried Y, it is possible to dry the material to be dried Y, and a huge tower or a reflection mirror is provided. It is possible to dry using solar heat without installing Further, compared to the amount of heat required to gasify a solid fuel such as coal, the amount of heat required for drying can be reduced, so in the drying system 1 of the present embodiment, a large number of gasification facilities are required. Not only does it not need to install a heliostat, there is no need for a complex control system that focuses from a widely installed heliostat to a limited range. Therefore, according to the drying system 1 of this embodiment, the enlargement of an installation and the complication of a control system can be suppressed.

Furthermore, according to the drying system 1 of the present embodiment, the heat transfer medium X is heated by solar heat instead of directly heating the material to be dried Y by the solar heat collected by the solar collector 2, and this heat transfer medium A configuration is employed in which the object to be dried Y is heated by X. Therefore, the temperature of the object to be dried Y can be easily adjusted by adjusting the physical properties (for example, saturated vapor temperature) of the heat transfer medium X, the flow velocity of the heat transfer medium X at the time of heat exchange, and the like. For example, in the drying system 1 of the present embodiment, since water is used as the heat transfer medium X, the temperature of the material to be dried Y can be prevented from becoming higher than the saturation temperature of water. The piping or the like through which the heat transfer medium X flows is a closed space, and the inside of the space is pressurized by vaporizing the heat transfer medium X. Therefore, in the drying system 1 of the present embodiment, the saturation temperature of the heat transfer medium X is, for example, about 160 ° C. to 170 ° C.

Therefore, according to the drying system 1 of the present embodiment as described above, the consumption of fuel used for drying can be suppressed by using solar heat. Moreover, the enlargement of the equipment can be suppressed. Furthermore, it becomes possible to adjust the temperature of the material to be dried Y to a temperature suitable for drying.

Further, in the drying system 1 of the present embodiment, the heat transfer medium X which is disposed between the solar collector 2 and the drying furnace 5 and is vaporized by being heated by the solar collector 2 is temporarily used. The steam drum 3 stored in the Therefore, even if there is a variation in the heating performance of each solar collector 2 due to, for example, the arrangement or individual differences and there is a difference in the ability to generate steam, all the steam is collected on the steam drum 3 once, Since the steam drum 3 is supplied to the drying furnace 5, the heat transfer medium X can be stably supplied to the drying furnace 5 at all times. Further, even if the sun is temporarily hidden in the cloud and the solar collector 2 can not sufficiently generate steam, for example, because a certain amount of steam is accumulated inside the steam drum 3, the drying furnace 5 is not The supply of steam can be continued.

Further, in the drying system 1 of the present embodiment, the material to be dried Y flows in the chamber 5a by supplying the fluidization gas Z from the fluidization gas supply device 6 into the chamber 5a. For this reason, the heat exchange between the material to be dried Y and the heat transfer medium X is promoted, and the material to be dried Y can be dried in a shorter time. Further, the fluidizing gas supply device 6 supplies the inert gas as the fluidizing gas Z to the drying furnace 5. Therefore, oxygen does not enter the chamber 5 a of the drying furnace 5, and it is possible to prevent the material Y to be dried from burning in the drying furnace 5 in any case.

Moreover, in the drying system 1 of this embodiment, the auxiliary | assistant boiler 4 which heats the heat transfer medium X separately from the solar heat collector 2 is provided. For this reason, when the steam required by the drying furnace 5 can not be generated in the solar heat collector 2, the material to be dried Y can be dried by generating the steam by the auxiliary boiler 4. For example, by operating the auxiliary boiler 4 before and after the sunrise time and before and after the sunset time, it is possible to extend the drying operable period (period in which the material to be dried Y can be dried) as described above. It becomes.

Moreover, in the drying system 1 of this embodiment, the control apparatus 8 operates the auxiliary boiler 4 according to at least one of sunrise time and sunset time. Therefore, as described above with reference to FIGS. 4 to 6, it is possible to secure a longer drying operation possible period as compared to the case where the auxiliary boiler 4 is not used.

Second Embodiment
Next, a second embodiment of the present disclosure will be described with reference to FIGS. In the description of the present embodiment, the description of the same parts as those in the first embodiment will be omitted or simplified.

FIG. 6 is a flow diagram showing a schematic configuration of the drying system 1A of the present embodiment. As shown to this figure, drying system 1A of this embodiment is the solar superheater 10 (superheater) with respect to the drying system 1 of the said 1st Embodiment, Fluidization vapor | steam supply part 11 (fluidization gas supply) Means, a superheated steam supply unit).

The solar heater 10 is disposed between the steam drum 3 and the drying furnace 5. The solar superheater 10 has a configuration similar to that of the solar heat collector 2, and the heat transfer medium X supplied from the steam drum 3 to the heat transfer tube 5c of the drying furnace 5 has a saturation temperature (for example 200). Temperature rise to approx. In addition, although 1 A of solar superheaters 10 are provided in the drying system 1A of this embodiment, it is also possible to employ a structure provided with a plurality of solar superheaters 10.

The fluidized steam supply unit 11 includes a superheated steam supply pipe 11 a and an on-off valve 11 b. The superheated steam supply pipe 11a is a pipe that connects the solar superheater 10 and the bottom of the chamber 5a, and supplies the heat transfer medium X heated by the solar superheater 10 into the chamber 5a as a fluidizing gas. The on-off valve 11b is disposed in the middle of the superheated steam supply pipe 11a, and opens and closes the flow path formed by the superheated steam supply pipe 11a. The on-off valve 11 b is controlled by, for example, the control device 8.

In the drying system 1A of this embodiment having such a configuration, the heat transfer medium X of the steam discharged from the steam drum 3 is heated by the solar superheater 10 to a temperature higher than or equal to the saturation temperature. It is supplied to the heat pipe 5c. Therefore, the heat transfer medium X having a high temperature is supplied to the heat transfer pipe 5 c of the drying furnace 5 as compared with the drying system 1 of the first embodiment. Therefore, the drying temperature in the drying oven 5 can be further raised, and the material to be dried Y can be dried in a short time.

Further, in the drying system 1A of the present embodiment, the control device 8 opens the on-off valve 11b as needed while the heat transfer medium X is overheated by the solar superheater 10. By opening the on-off valve 11b as described above, the heat transfer medium X is supplied as fluidizing gas into the chamber 5a through the superheated steam supply pipe 11a. When the heat transfer medium X is brought into direct contact with the material to be dried Y when the temperature in the chamber 5a is low, for example, at the start of operation of the drying system 1A, the heat transfer medium X condenses and the surface of the material to be dry Y But the flow of the substance to be dried Y is inhibited. For this reason, when the temperature in the chamber 5a is low, the fluidizing gas supply device 6 supplies the fluidizing gas Z consisting of an inert gas to the chamber 5a as in the drying system 1 of the first embodiment.

Subsequently, an example of the operation pattern in the drying system 1A of the present embodiment will be described with reference to FIGS. 7 to 9.

FIG. 7 is an explanatory view of the case where the auxiliary boiler 4 is operated only before and after the sunrise time in the drying system 1A of the present embodiment. Moreover, FIG. 8 is explanatory drawing in the case where the auxiliary | assistant boiler 4 is operated only before and behind sunset time in the drying system 1A of this embodiment. FIG. 9 is an explanatory diagram of the case where the auxiliary boiler 4 is operated before and after the sunrise time and before and after the sunset time in the drying system 1A of the present embodiment.

As shown in FIG. 7, when the auxiliary boiler 4 is operated before and after the sunrise time, the operation of the auxiliary boiler 4 is started before the sunrise. At the start of operation, the preheating operation is performed as in the drying system 1 of the first embodiment. However, during this time, the temperature of the heat transfer medium X does not reach the boiling point, and the heat transfer medium X (superheated steam) overheated in the solar superheater 10 is not generated. The fluidization gas Z comprising the above is supplied to the chamber 5a, and the material to be dried Y remaining in the chamber 5a in the operation of the previous day is made to flow.

When the sunrise time passes and the temperature of the heat transfer medium X reaches the boiling point, a new material to be dried Y is supplied to the chamber 5a and the drying operation is started. Furthermore, when the heat transfer medium X heated by the solar superheater 10 is generated, the supply of the inert gas chamber 5a by the fluidizing gas supply device 6 is stopped, and the heat transfer medium heated by the solar superheater 10 The chamber 5a is supplied as X as a fluidizing gas. Even when the inert gas is circulated, a constant amount leaks and it becomes necessary to replenish it. Therefore, the supply of the inert gas is stopped and the overheated heat transfer medium X is supplied as the fluidizing gas. The amount of active gas used can be reduced, and operating costs are reduced.

When the sunset time approaches and energy for superheating by the solar superheater 10 can not be obtained, the supply of the heat transfer medium X from the fluidizing steam supply unit 11 to the chamber 5a is stopped, and the fluidizing gas supply device 6 to the chamber 5a Resume the supply of inert gas to the Then, when the temperature approaches the sunset time, the temperature is switched to the cooling operation at the timing when the temperature of the heat transfer medium X falls below the saturation temperature, and then the operation is stopped.

As described above, by operating the auxiliary boiler 4 before and after the sunrise time, it is possible to advance the start timing of the drying operable period, and it is possible to dry the object to be dried Y in a longer period.

As shown in FIG. 8, when the auxiliary boiler 4 is operated before and after the sunset time, the operation of the auxiliary boiler 4 is started before the sunset. As a result, it is possible to suppress the decrease in the temperature of the heat transfer medium X before and after the sunset time. Therefore, the temperature of the heat transfer medium X can be maintained at the boiling point for a while even after the sunset time, and the drying of the material to be dried Y can be continued. However, while the auxiliary boiler 4 is in operation, the heat transfer medium X can not be overheated by the solar superheater 10 because the energy obtained from the sun is small. Therefore, during this period, the supply of the heat transfer medium X from the fluidizing vapor supply unit 11 to the chamber 5a is stopped, and the fluidizing gas Z comprising the inert gas is supplied from the fluidizing gas supply device 6 to the chamber 5a. In this manner, by operating the auxiliary boiler 4 before and after the sunset time, it is possible to extend the drying operable period to after the sunset time as shown in FIG. It is possible to dry the

Further, as shown in FIG. 9, when the auxiliary boiler 4 is operated before and after the sunrise time and before and after the sunset time, the start timing of the drying operation possible period is advanced, and furthermore, the drying operation possible period is sunset. It is possible to extend until after the time.

According to the drying system 1A of the present embodiment as described above, the solar superheater 10 that further raises the temperature of the heat transfer medium X heated by the solar heat collector 2 is provided. For this reason, the drying temperature in the drying furnace 5 can be further raised, and the material to be dried Y can be dried in a short time. Furthermore, according to the heat transfer medium X heated to the saturation temperature or higher, the temperature is sufficiently high, and therefore, even when contacting the material to be dried Y during the drying, the aggregation does not occur. Therefore, the heat transfer medium X can be used as a fluidizing gas, and the amount of inert gas used can be reduced.

Third Embodiment
Next, a third embodiment of the present disclosure will be described with reference to FIG. In the description of the present embodiment, the description of the same parts as those in the first embodiment or the second embodiment will be omitted or simplified.

FIG. 10 is a flowchart showing a schematic configuration of the drying system 1B of the present embodiment. As shown in this figure, the drying system 1B of the present embodiment is juxtaposed to a boiler power generation system 100 that uses the to-be-dried material Y (brown coal) dried by the drying system 1B of the present embodiment as fuel. With respect to the drying system 1A of the embodiment, a configuration including an intermediate pressure turbine extraction unit 12, a drying steam superheater 13 (superheater), and a low pressure turbine extraction unit 14 is employed.

The configuration is not particularly limited, but the boiler power generation system 100 includes a boiler 101 that burns the material to be dried Y to generate steam, and a turbine 102 that generates rotational power using the steam obtained by the boiler 101. There is. Although not shown in FIG. 10, the boiler power generation system 100 includes a generator or the like that generates electric power using the rotational power generated by the turbine 102. In the present embodiment, the turbine 102 is a three-stage turbine including a high pressure turbine 102a, an intermediate pressure turbine 102b, and a low pressure turbine 102c.
The boiler 101 also includes a reheater 101a that reheats the steam discharged from the high pressure turbine 102a and supplies the reheated steam to the intermediate pressure turbine 102b.

The intermediate pressure turbine extraction unit 12 includes an extraction pipe 12 a and an on-off valve 12 b. The bleed pipe 12a is a pipe that passes the drying steam superheater 13 and connects the intermediate pressure turbine 102b and the low pressure turbine 102c. The on-off valve 12b is disposed at an intermediate position of the bleed pipe 12a, and opens and closes a flow path formed by the bleed pipe 12a. The on-off valve 12 b is controlled by, for example, the control device 8. Such an intermediate pressure turbine extraction unit 12 extracts steam from the intermediate pressure turbine 102b, guides the extracted steam so as to pass through the drying steam superheater 13, and supplies it to the low pressure turbine 102c.

The drying steam heater 13 is provided in parallel to the solar heater 10 between the steam drum 3 and the drying 5. The drying steam superheater 13 exchanges heat between the steam extracted from the intermediate pressure turbine 102 b by the intermediate pressure turbine extraction unit 12 and the heat transfer medium X disposed from the steam drum 3 to obtain a heat transfer medium X Further raise the temperature.

The low pressure turbine extraction unit 14 includes an extraction pipe 14 a and an on-off valve 12 b. The bleed pipe 12 a is connected to the low pressure turbine 102 c and guides the steam extracted from the low pressure turbine 102 c toward the heat transfer pipe 5 c of the drying furnace 5. The on-off valve 14b is disposed at an intermediate position of the bleed pipe 14a, and opens and closes the flow path formed by the bleed pipe 14a. The on-off valve 14 b is controlled by, for example, the control device 8. Such a low pressure turbine extraction unit 14 extracts steam from the low pressure turbine 102 c and supplies the steam to the heat transfer pipe 5 c of the drying furnace 5.

According to the drying system 1B of the present embodiment as described above, the drying steam superheater 13 that further raises the temperature of the heat transfer medium X heated by the solar collector 2 is provided. For this reason, the drying temperature in the drying furnace 5 can be further raised, and the material to be dried Y can be dried in a short time. Furthermore, according to the heat transfer medium X heated to the saturation temperature or higher, the temperature is sufficiently high, and therefore, even when contacting the material to be dried Y during the drying, the aggregation does not occur. Therefore, the heat transfer medium X can be used as a fluidizing gas, and the amount of inert gas used can be reduced.

Further, in the drying system 1B of the present embodiment, a part of the steam extracted from the low pressure turbine 102c can be supplied to the heat transfer tube 5c of the drying furnace 5. Therefore, when the flow rate of the heat transfer medium X discharged from the steam drum 3 is small, it can be compensated by the steam from the low pressure turbine 102c. Therefore, the drying operable period can be extended, and it is also possible to operate the drying system 1B, for example, for 24 hours.

Although the preferred embodiments of the present disclosure have been described above with reference to the drawings, the present disclosure is not limited to the above-described embodiments. The shapes, combinations, and the like of the constituent members shown in the above-described embodiment are merely examples, and various changes can be made based on design requirements and the like without departing from the spirit of the present disclosure.

For example, in the said embodiment, the structure using what is called a fluid bed type which dries while fluidizing the to-be-dried material Y as the drying furnace 5 was demonstrated. However, the present disclosure is not limited thereto, and it is also possible to use other drying ovens. For example, it is also possible to adopt a configuration using a moving bed type drying furnace in which the material to be dried Y is supplied to the inclined surface and drying is performed while moving the material to be dried Y by weight. However, in the fluidized bed type drying oven 5 described in the above embodiment, the moving distance of the material to be dried Y can be easily changed by the arrangement interval of the dividing wall 5b, etc. It is advantageous in that it can be adjusted to

Moreover, in the said embodiment, the structure which drive | operates the auxiliary | assistant boiler 4 in the sunrise time and / or the sunset time was demonstrated. However, the present disclosure is not limited thereto, and the auxiliary boiler 4 may be operated in cloudy or rainy weather. In such a case, for example, the control device 8 determines whether or not to operate the auxiliary boiler 4 based on a sensor that detects weather or weather information input from the outside.

According to the present disclosure, in a drying system for drying a fuel or the like containing a large amount of water, consumption of fuel used for drying is suppressed by using solar heat, and enlargement of facilities is suppressed, and drying is suitable. The temperature of the material to be dried can be made adjustable.

DESCRIPTION OF SYMBOLS 1 drying system

1A drying system

1B drying system 2 solar heat collector 2a 1st reflective plate 2b 2nd reflective plate 2c heat transfer tube 2d drive device 2e support part 2f collecting pipe 3 steam drum 4 auxiliary boiler 5 drying furnace 5a chamber 5b divided wall 5b1 first divided wall 5b2 second divided wall 5c heat transfer pipe 6 fluidizing gas supply device (fluidizing gas supply means, inert gas supply unit)
6a circulation pipe 6b inert gas generator 6c blower 6d heat exchanger 6e cooler 7 heat transfer medium circulation unit 7a return pipe 7b condenser 7c feed water pump 7d feed water preheater 7e steam drum connection pipe 8 control device 10 solar heating 11 Fluidizing steam supply unit (fluidizing gas supply means, superheated steam supply unit)
11a Superheated steam supply piping 11b opening and closing valve 12 medium pressure turbine extraction part 12a extraction piping 12b opening and closing valve 13 steam heater for drying (superheater)
14 low pressure turbine extraction part 14a extraction pipe 14b on-off valve 100 boiler power generation system 101 boiler 101a reheater 102 turbine 102a high pressure turbine 102b medium pressure turbine 102c low pressure turbine X heat transfer medium Y to-be-dried matter Z fluidization gas

Claims

A plurality of solar collectors that heat the heat transfer medium with solar heat and are provided in plural;
A drying furnace for drying the material to be dried by heat exchange between the heat transfer medium heated by the solar collector and the material to be dried.
The steam drum according to claim 1, further comprising a steam drum disposed between the solar collector and the drying furnace and temporarily storing the heat transfer medium vaporized by being heated by the solar collector. Drying system.
The drying system according to claim 1, further comprising a superheater that further raises the temperature of the heat transfer medium heated by the solar collector.
The drying system according to any one of claims 1 to 3, further comprising: fluidizing gas supply means for fluidizing the material to be dried in the drying oven by supplying the fluidization gas to the drying oven.
The drying system according to claim 4, further comprising: a superheated steam supply unit configured to supply the superheated steam as the fluidizing gas to the drying furnace as the fluidizing gas supply means.
The drying system according to claim 4 or 5, further comprising an inert gas supply unit configured to supply an inert gas as the fluidization gas to the drying furnace as the fluidization gas supply unit.
The drying system according to any one of claims 1 to 6, further comprising an auxiliary boiler that heats the heat transfer medium separately from the solar collector.
The drying system according to claim 7, further comprising a control device that operates the auxiliary boiler in accordance with at least one of sunrise time and sunset time.