KR20160089455A - Method for producing ashless coal - Google Patents

Abstract

The thermal energy held by the solvent in the vapor state generated in the extraction process (for example, the extraction tank) and / or the ashless coal acquisition process (for example, the flasher) is controlled by at least one process for producing ashless coal, Or used as a heat source in the dehydration process (dehydration tank) (heaters for slurry dewatering), or heat recovery in a batch recovery boiler as thermal energy of steam.

Description

[0001] METHOD FOR PRODUCING ASHLESS COAL [0002]

The present invention relates to a method for producing ashless coal for obtaining ashless coal from which ash is removed from coal.

As a method of producing the ashless carbon, for example, there is one described in Patent Document 1. In Patent Document 1, a slurry is prepared by mixing coal and a solvent, heating the obtained slurry to extract a coal component soluble in the solvent, separating a solution containing a coal component soluble in the solvent from the slurry from which the coal component is extracted And recovering the solvent from the separated solution to obtain an ashless coal.

Japanese Patent No. 4045229

In the process for producing ashless coal, the coal and the solvent in a state such as slurry are heated in most of the processes. That is, thermal energy is given to the coal and the solvent. This heat energy (heating energy) is introduced from the outside of the process in the form of, for example, high-pressure steam, low-pressure steam or electricity.

Here, when used in any one of the processes for producing the ashless coal without disposing the arrays generated in the process of introducing thermal energy, it is possible to reduce the heat energy (heating energy) newly introduced from the outside of the process system, As a result, it is considered that the manufacturing cost of the unfired carbon (the running cost of the unfired manufacturing facility) can be reduced as compared with the conventional one. However, this does not mean that the present invention can be effectively utilized to contribute to the reduction of the manufacturing cost of the arrangement and the ashless carbon during the process of introducing thermal energy. The slurry or the like can not be efficiently heated even if the temperature of the resulting arrangement is excessively low or the amount of heat generated is too small. That is, the arrangement can not be used so as to contribute to the reduction of manufacturing cost of the ashless carbon. In this way, it is not possible to reduce the production cost of the ashless coal in the facility of the scale scale simply by using the arrangement generated in the process of introducing thermal energy.

In addition, the method of extracting the arrays generated in the step of introducing thermal energy is not a simple method, and does not contribute to the reduction of manufacturing cost of the ashless carbon. This is because, if the array taking out method is complicated, the equipment is complicated and accordingly, the introduction cost of the equipment is increased, and the labor cost of the operation is also increased.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a manufacturing method of ashless coal having a process of array use capable of reducing the manufacturing cost of the ashless coal (running cost of the ashless coal manufacturing facility) .

The present invention relates to a slurry producing method comprising: a slurry preparing step of mixing a coal and a solvent to prepare a slurry; an extraction step of extracting a coal component soluble in the solvent by heating the slurry obtained in the slurry preparing step; A separation step of separating the solvent into a solution containing a coal component soluble in the solvent and a solid concentrate in which a coal component insoluble in the solvent is concentrated; and a step of separating the solvent from the solution separated in the separation step, And an unburned carbon obtaining process for obtaining carbon. In this method for producing an ashless coal, it is preferable that the thermal energy held by the solvent in a vapor state generated in at least one of the extraction step and the non-recycle acquisition step is higher than the thermal energy held in at least one step At least one of the use as a heat source and the heat recovery from a batch recovery boiler as thermal energy of steam.

According to the present invention, the heat energy generated in the process for producing ashless coal can be effectively used for manufacturing ashless coal in a simple and effective manner. As a result, the production cost of the ashless coal (running cost of the ash production facility) Can be reduced.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a block diagram showing an ashless coal manufacturing facility for explaining a production method of an ashless coal according to a first embodiment of the present invention. FIG.
2 is a block diagram showing an ash tundish manufacturing facility for explaining a manufacturing method of the ashless coal according to the second embodiment of the present invention.
3 is a block diagram showing an ashless coal manufacturing facility for explaining a production method of an ashless coal according to a third embodiment of the present invention.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(First Embodiment)

As shown in FIG. 1, the ashless coal manufacturing facility 100 includes a coal hopper 1, a solvent tank 2, a slurry tank 3, a feed pump 3, The first gravity incineration accelerator 9, the second gravity incineration accelerator 10 and the flasher (solvent separator) 4, the dehydrating tank 5, the transfer pump 6, the preheater 7, the extraction tank 8, (11, 12).

The ashless coal manufacturing facility 100 includes a high temperature recovery solvent tank 15, a transfer pump 16, a first heat exchanger 17 And an arrangement recovery boiler 18.

As a series of devices for effectively utilizing heat energy generated in the flasher 11 (solvent separator for ashlessoning), the ashless coal manufacturing facility 100 includes a second heat exchanger 13 and a slurry dewatering heater 14 .

In addition, as a device for effectively utilizing heat energy generated in the flasher 12 (solvent separator for byproducts), the ashless coal manufacturing facility 100 is provided with an arrangement recovery boiler 19.

Here, the method for producing ashless coal has a slurry preparation step, a slurry dewatering step, an extraction step, a separation step, an unburned carbon acquisition step, and a by-product tank acquisition step. Each of these steps will be described below. In addition, explaining each of these steps, the effective utilization of the heat energy generated in the manufacturing process of the ashless coal will be described.

The coal to be used as the raw material in the present production method is not particularly limited, and bituminous coal having a high extraction ratio (ratio of soluble components of coal extracted in the solvent) may be used as a raw material, and cheaper crude zeolite (bituminous coal, lignite) May be used as a raw material. The term "ashless coal" means that the ash content is 5% by weight or less, preferably 3% by weight or less.

<Slurry Preparation Process>

The slurry preparing step is a step of mixing coal and a solvent to prepare a slurry. The slurry preparation process is carried out in slurry preparation (3) in Fig. The raw coal is charged into the slurry tank 3 from the coal hopper 1 and the solvent is introduced into the slurry tank 3 from the solvent tank 2. The coal and the solvent put in the slurry preparation 3 are mixed by the agitator 3a to form a slurry containing coal and a solvent.

The mixing ratio of coal to the solvent is, for example, 0.5 to 4.0 based on dry coal, and more preferably 0.75 to 2.0.

&Lt; Slurry dewatering step &

The slurry dewatering step is a step of dehydrating the slurry by preheating the slurry obtained (produced) in the slurry preparing step. The slurry dewatering process is carried out in the dehydration tank 5 in Fig. The slurry prepared in the slurry preparation (3) is supplied to the dehydration tank (5) by the feed pump (4). The slurry supplied to the dehydrating tank 5 is mixed by the stirrer 5a while being heated by the heated slurry sent from the slurry dewatering heater 14. As a result, the moisture contained in the slurry evaporates, and the amount of water in the slurry decreases. The slurry in the dewatering tank 5 is drained from the bottom of the dewatering tank 5 by the transfer pump 6 and then drained from the top of the dewatering tank 5 via the slurry dewatering heater 14 (5).

In the slurry dewatering heater 14, the slurry is generated by the flasher 11 and heated by the heat energy held by the vaporized solvent sent to the pipe 21. As a result, it is possible to reduce the thermal energy for dewatering the slurry newly introduced from the outside of the process.

The dehydration temperature of the slurry in the slurry dewatering step is a temperature higher than the boiling point of water and lower than the boiling point of the solvent, for example, 100 to 150 캜.

The slurry dewatering step may be omitted when the amount of water contained in the raw coal is small. When the slurry dewatering step is omitted, the slurry prepared in the slurry preparation step is directly sent to the next extraction step (see, for example, FIG. 2 in which the dewatering tank 5 is not installed).

<Extraction Process>

The extraction step is a step of heating the slurry dewatered in the slurry dewatering step to extract (soluble in a solvent) a coal component soluble in the solvent. The extraction process is carried out in the preheater 7 and the extraction tank 8 in Fig. The slurry dewatered in the dewatering tank 5 is supplied to the preheater 7 by the transfer pump 6 and heated to a predetermined temperature and then supplied to the extraction tank 8 and stirred by the agitator 8a The extraction is carried out while being maintained at the predetermined temperature.

Here, in the present embodiment, the slurry dewatered in the dewatering tank 5 is fed to the preheater 7 via the second heat exchanger 13 by the feed pump 6. The slurry in the second heat exchanger 13 is generated by the flasher 11 and is heated by the thermal energy held by the vaporized solvent sent to the pipe 21. As a result, the heat capacity of the preheater 7 can be made smaller than in the prior art. In other words, the heat energy (heating energy) newly introduced from outside the process system can be reduced.

The solvent in the vapor state generated in the extraction tank 8 is extracted from the top of the extraction tank 8 and flows through the pipe 22 to be supplied to the first heat exchanger 17 and the arrangement recovery boiler 18 Are supplied to these devices in order. Effective utilization of thermal energy in the first heat exchanger 17 will be described later. The heat energy generated in the extraction tank 8 and retained by the solvent remaining after passing through the first heat exchanger 17 is recovered as heat by the heat recovery boiler 18 as heat energy of the steam.

The water vapor (recovered heat energy) generated in the batch recovery boiler 18 can be used as steam in each step of manufacturing the ashless coal. Therefore, it is possible to reduce the amount of steam newly introduced from outside the process. Further, the solvent discharged from the batch recovery boiler 18 is circulated by being returned to the slurry preparation 3 (slurry preparation step). The circulating use of this solvent is also applied to the arrangement recovery boiler 19.

Refer to the solvent. When the slurry obtained by mixing the coal and the solvent is heated to extract the coal component soluble in the solvent, a solvent having a large dissolving power for coal, in most cases, an aromatic solvent (a solvent of a hydrogen donor or a non-hydrogen donor) , The coal is mixed and heated to extract the organic component in the coal.

The non-hydrogenated solvent is a coal derivative, which is a solvent mainly composed of a bicyclic aromatic group, which is mainly purified from a coal product of coal. Examples of the main components of the non-hydrogenated naphthalene solvents include naphthalene, naphthalene, methylnaphthalene, dimethylnaphthalene and trimethylnaphthalene, which are two-ring aromatic compounds, and naphthalenes and aliphatic dicarboxylic acids having aliphatic side chains, , Fluorenes, and alkylbenzenes having biphenyls or long chain aliphatic side chains therein. In addition, a hydrogen-containing compound represented by tetralin (including coal liquefied oil) may be used as a solvent.

The boiling point of the solvent is not particularly limited. From the viewpoints of the pressure reduction in the extraction step and the separation step, and the extraction ratio in the extraction step, for example, a solvent having a boiling point of 180 to 300 캜, particularly 240 to 280 캜, is preferably used.

The heating temperature of the slurry in the extraction step is not particularly limited as long as the solvent soluble component can be dissolved and is preferably 300 to 420 DEG C in view of sufficient dissolution of the solvent soluble component and improvement of the extraction ratio, Lt; / RTI &gt;

The extraction step is carried out in the presence of an inert gas such as nitrogen. The pressure in the extraction tank 8 is preferably from 1.0 to 2.0 MPa, depending on the temperature at the time of extraction and the vapor pressure of the solvent to be used. When the pressure in the extraction tank 8 is lower than the vapor pressure of the solvent, the solvent volatilizes and is not trapped in the liquid phase and can not be extracted. In order to confine the solvent in the liquid phase, a pressure higher than the vapor pressure of the solvent is required.

<Separation Process>

The separation step is a step of separating the slurry obtained in the extraction step into a solution containing a coal component soluble in a solvent and a solid concentrate (solvent insoluble matter concentrate) in which a coal component insoluble in a solvent is concentrated, for example, by gravity sedimentation . This separation step is carried out in the first gravitational forceps 9 and the second gravitational forceps 10 in Fig. The slurry obtained in the extraction step is separated into a supernatant as a solution and a solid concentrate by gravity in the first gravity sedimentation 9 and the second gravity sedimentation 10. The supernatant of the upper part of the gravity sedimentation accelerators 9 and 10 is sent to the flasher 11, respectively. The solid concentrate settled in the lower portion of the second gravity set precipitator 10 is sent to the flasher 12. In this embodiment, the gravitational sedimentation emphasis is two-stage (plural stages), but it may be one stage as shown in Fig. It is ideal that the supernatant and the solid concentrate are completely separated. However, in some cases, a solid content is mixed in a part of the supernatant, or a supernatant is mixed in a part of the solid content.

Further, the gravity sedimentation method is a method in which slurry is held in a vessel to sediment and separate the solvent insoluble component by gravity. As a method for separating the solution containing the coal component dissolved in the solvent from the slurry obtained in the extraction step, there are filtration method, centrifugal separation method and the like in addition to the gravitational sedimentation method.

In the gravity sedimentation accelerators 9 and 10, it is preferable to heat, heat or pressurize in order to prevent re-precipitation of the solvent-soluble components eluted from the coal. The heating temperature is, for example, 300 to 380 占 폚, and the pressure in the bath is, for example, 1.0 to 3.0 MPa.

Here, in the present embodiment, the second gravitational forceps 10 are kept warm (heated) by using the thermal energy held by the solvent in the vapor state generated in the extraction tank 8. The solvent stored in the high temperature recovery solvent tank 15 flows into the first heat exchanger 17 by the transfer pump 16 and is then supplied to the second gravity settler 10. In the first heat exchanger (17), the solvent is generated by the extraction tank (8) and heated by the heat energy held by the vaporized solvent sent to the piping (22). The heated solvent is supplied to the second gravitational forceps 10, so that the second gravitational forceps 10 is kept warm (heated). According to this configuration, the heat energy to be newly introduced from the outside of the process in the process can be reduced in order to maintain (heat) the inside of the second gravitational forceps 10.

<Acquisition process of ashyo coal>

In the ash recovery step, the solvent is evaporated and separated from the solution (supernatant) separated in the above separation step to obtain ashless coal. This uncyclopedia acquisition process is carried out in the flasher 11 in Fig. The solution separated from the gravity sedimentation accelerations 9 and 10 is supplied to the flasher 11 and the solvent is evaporated and separated from the supernatant in the flasher 11. [

The pressure in the tank of the flasher 11 is, for example, 0.1 MPa (normal pressure). As a result, the solution separated from the gravitational sedimentation 9, 10 is ejected into the flasher 11, and the solvent in the solution is evaporated from the solution (flash distillation method). Thereby, an ash-free coal substantially free of ash (for example, having a by-product of 3 wt% or less) is obtained.

Further, the method of separating the solvent from the solution (supernatant) is not limited to the flash distillation method. As another separation method, for example, a thin film distillation method can be mentioned. The thin film distillation method is a method in which a distillation target (a solution separated in the separation step in the present invention) is introduced into a tank (thin film distillation tank) containing a scraper (also referred to as a wiper) and a thin film to be distilled is formed on the inner wall of the tank by a scraper And distillation is carried out continuously. The inner wall of the bath is heated from the outside. The pressure in the tank (thin film distillation tank) is, for example, 0.1 MPa (normal pressure).

On the other hand, the vaporized solvent separated from the solution is extracted from the top of the flasher 11, flows through the pipe 21, and is supplied to the second heat exchanger 13 and the slurry dewatering heater 14 in this order. And supplied to each device. The solvent discharged from the slurry dewatering heater 14 enters the high temperature recovery solvent tank 15.

<Process for obtaining by-products>

The by-product burning step is a step for obtaining by-products by evaporating and separating the solvent from the solid concentrate separated in the separation step. This by-product burning process is carried out in the flasher 12 in Fig. The solid concentrate separated in the second gravity sedimentation accelerator 10 is supplied to the flasher 12 and the solvent is evaporated from the solid concentrate in the flasher 12 (flash distillation). In addition, the process for obtaining by-products is not an essential process.

The pressure in the tank 12 of the flasher 12 is, for example, 0.1 MPa (atmospheric pressure) in the same manner as the flasher 11 for ashing. In addition, the method of separating the solvent from the solid concentrate is not limited to the flash distillation method. By separation of the solvent, by-product carbon (RC, also referred to as residual product) in which a solvent insoluble component including ash and the like is concentrated can be obtained from the solid component concentrate.

Here, in the present embodiment, the thermal energy held by the vapor-state solvent generated in the flasher 12 is heat-recovered by the arrangement recovery boiler 19 as thermal energy possessed by steam. The solvent in the vapor state separated from the solid concentrate is extracted from the top of the flasher 12 and supplied to the arrangement recovery boiler 19. The steam (recovered heat energy) generated in the batch recovery boiler 19 can be used as steam in each step of manufacturing the ashless coal. Therefore, it is possible to reduce the amount of steam newly introduced from outside the process.

&Lt; Heat energy generated in the ash-free manufacturing process >

Examples of effective heat energy generated in the ash-free manufacturing process are summarized in Table 1. As can be seen from Table 1, the temperature of the heat energy generated in the extraction process (extraction tank 8) is as high as 400 ° C at maximum. The temperature of the heat energy generated in the ash recovery process (in the case of the flasher 11) is about 270 ° C at the maximum, which is lower than the temperature of the heat energy generated in the extraction process (extraction tank 8) 1.08 MMkcal / ton- Coal throughput is large. The "/ ton-coal throughput" means that 1 ton of coal is treated. Also, in Table 1, the device generated in the ashlesson obtaining process refers to the case where the flasher 11 (flash distillation method) is used in the ash recovery process as illustrated in Fig. The device that is generated in the ash recovery process is referred to as a thin film distillation tank when the thin film distillation tank (thin film distillation method) is used in the ash recovery step (also in Table 2).

<Where to use heat energy>

Table 2 shows an example of utilization of the thermal energy shown in Table 1 that occurs in the ash-free manufacturing process.

As shown in Table 1, since the temperature of the heat energy generated in the extraction process (extraction tank 8) is as high as 400 ° C at maximum, the extraction process (extraction tank 8) Can be applied as a heating source in various processes such as a slurry dewatering process, an extraction process, a separation process, and a steam recovery process.

On the other hand, the temperature of the heat energy generated in the flasher in the ash recovery process is about 270 ° C at the maximum, which is lower than the temperature of the heat energy generated in the extraction process (extraction tank 8). As a result, the heat energy generated by the flasher in the ash recovery process is not suitable for heating the object at 300 ° C. or higher, but the heat quantity is 1.08 MM kcal / ton-coal, It is suitable for heating on.

On the other hand, when a thin film distillation tank (thin film distillation method) is used in the ash recovery step, the temperature of the heat energy generated there is at most 300 ° C, which is higher than in the flasher (flash distillation method) However, since the amount of heat energy generated from the thin-film distillation tank is not so large as about 0.024 MMKcal / ton-coal throughput, it can be used as a heating source for heating the slurry in the slurry dewatering step or the extraction step, It is better to use it as a circle.

The calorific value of the heat energy generated in the flasher of the by-product burning process is 0.144 MMKcal / ton-coal throughput, which is larger than that of the heat energy generated from the thin film distillation tank. Therefore, the thermal energy generated in the flasher of the by-product burning process is suitable not only for use as a heating source for steam recovery but also for use as a heating source for heating slurry in a slurry dewatering process or an extraction process .

&Lt; Specific reduction amount of heat energy newly introduced from the outside of the process >

The ashless carbon production equipment 100 illustrated in Figure 1, in the slurry for dewatering a heater ^{(14) 4.9 × 10 3 kcal} / ton- coal throughput, in the first heat exchanger ^{(17) 3.7 × 10 3 kcal} / ton - the throughput of the coal, and the heat of the 13.6 × 10 ³ kcal / ton-coal throughput in the second heat exchanger 13 can be supplied by the heat energy generated from the process (apparatus) of the ashless coal production. Further, the heat of 3.4 x 10 ³ kcal / ton-coal throughput can be recovered in the batch recovery boiler 19 to produce steam.

<Action / Effect>

In the present invention, in each of the processes for producing the ashless coal, the thermal energy held by the vapor-state solvent generated in at least one of the extraction process and the non-recycle process is changed in at least one step And heat recovery from the heat recovery boiler as heat energy of the steam.

For example, heat is generated also in the slurry dewatering process (dehydration tank 5) and the separation process (gravity deposition 9, 10) in the ashlesson production facility 100 shown in Fig. However, the temperature of the heat generated in these processes is low, and the amount of heat is small. On the other hand, the temperature of the heat generated in the extraction process (extraction tank 8), the non-recycle acquisition process (for example, the flasher 11), and the by-product recovery process (for example, the flasher 12) is high. Even though the temperature of the heat is not remarkably high (which is higher than the temperature of heat generated in the slurry dewatering step and the separation step), the amount of heat is large. Therefore, the heat energy generated in these processes can be used as a heat source in at least one process for producing the ashless coal, or the heat can be recovered from the batch recovery boiler as thermal energy possessed by steam, And can be effectively used effectively in production.

Further, in the present invention, the generated heat energy is treated as heat energy held by the vapor-state solvent. The solvent in the vapor state can easily be sent by connecting pipes between apparatuses. That is, the vaporized solvent is easy to handle.

As described above, according to the present invention, the thermal energy generated in the process for producing ashless coal can be effectively used in a simple and effective manner for the production of ashless coal. As a result, the production cost of the ashless coal Running cost) can be reduced.

Here, in the present embodiment, the heat energy held by the solvent in the vapor state generated in the extraction step (extraction tank 8) is supplied to the heat source for heating the solvent in the separation step (second gravitational forceps 10) As shown in FIG. Since the temperature of the heat energy generated in the extraction process (extraction tank 8) is as high as 400 DEG C at maximum, the gravity sedimentation can be effectively kept warm (heated) by the heat energy.

In the present embodiment, the heat energy held by the solvent in the vapor state generated in the extraction step (extraction tank 8) is supplied to the heat source for heating the solvent in the separation step (second gravity precipitate 10) And the remaining heat energy is recovered by the heat recovery boiler 18 as heat energy of the steam. According to this configuration, the remaining heat energy can be recovered in the arrangement recovery boiler 18, and the arrangement for throwing away the waste can be minimized.

Further, by supplying the vaporized solvent generated in the extraction step (extraction tank 8) directly to the batch recovery boiler 18, almost all of the thermal energy retained by the solvent in the vapor state can be detected It is also preferable that heat is recovered from the batch recovery boiler 18 as thermal energy. The steam (recovered heat energy) generated in the batch recovery boiler 18 can be used as low-pressure steam in each step of manufacturing the ashless coal. Therefore, it is possible to reduce the amount of low-pressure steam newly introduced from outside the process.

Further, in the present embodiment, the thermal energy held by the solvent in the vapor state generated in the ashless coal obtaining step (for example, the flasher 11) is used for heating the slurry in the extraction step (extraction tank 8) And is used as a heat source (second heat exchanger 13). The heating amount of the slurry in the preheater 7 can be reduced by using the heat energy generated in the ash recovery step (for example, the flasher 11) as the energy for heating the slurry. As a result, the heat energy (heating energy) newly introduced from outside the process system can be reduced.

Further, in the present embodiment, the thermal energy held by the solvent in the vapor state generated in the ashless coal obtaining step (for example, the flasher 11) is used for heating the slurry in the extraction step (extraction tank 8) After being used as a heat source, the remaining heat energy is used as a heat source for slurry dewatering in the slurry dewatering step (dewatering tank 5) (heater for dewatering slurry 14). As shown in Table 1, since the amount of heat energy generated in the ash recovery process (flasher 11) is large, for example, at 1.08 MM kcal / ton-coal throughput, The slurry can be heated.

In the present embodiment, the thermal energy retained in the vapor state solvent generated in the by-product burning step (flasher 12) is recovered by the arrangement recovery boiler 19 as heat energy possessed by steam. As in the case where the heat recovered in the vapor-phase solvent in the extraction process (extraction tank 8) is recovered by the heat recovery boiler 18 as thermal energy possessed by the vapor, according to this configuration, The steam (recovered heat energy) generated in the boiler 19 can be used as steam in each process for producing ashless coal, so that the amount of steam newly introduced from the outside of the process can be reduced.

(Second Embodiment)

The ashless coal manufacturing facility 101 shown in Fig. 2 will be described. With regard to the equipment constituting the ashless coal manufacturing facility 101, the same components as those of the equipment constituting the ashless coal manufacturing facility 100 shown in Fig. 1 are denoted by the same reference numerals.

In the present embodiment, not the thermal energy held by the solvent in the vapor state generated in the uncyricer acquiring step (for example, the flasher 11), but the solvent in the vapor state generated in the extraction step (extraction tank 8) The heat energy to be retained is used as a heat source for heating the slurry in the extraction process (extraction tank 8). Structurally, the vapor-state solvent generated in the extraction process (extraction tank 8) is sent to the second heat exchanger 13 via the pipe 22, where the slurry before entering the preheater 7 Heating.

According to this configuration, by using the heat energy generated in the extraction step (extraction tank 8) as energy for heating the slurry in the extraction step (extraction tank 8), the slurry in the preheater 7 It is possible to reduce the amount of heating. As a result, the heat energy (heating energy) newly introduced from outside the process system can be reduced.

Further, in the present embodiment, the remaining heat energy is recovered by the heat recovery boiler 18 as heat energy of the steam.

In the present embodiment, the heat energy retained by the solvent in the vapor state generated in the unburned gas obtaining step (for example, the flasher 11) is recovered as heat energy in the steam by the heat recovery boiler 19 have. Structurally, the solvent in the vapor state generated in the ash recovery process (for example, the flasher 11) is sent to the arrangement recovery boiler 19 via the pipe 21, where steam is generated.

According to this configuration, the steam (recovered heat energy) generated in the arrangement recovery boiler 19 can be used as low-pressure steam in each step of manufacturing the ashless coal, thereby reducing the amount of low-pressure steam newly introduced from outside the process can do.

(Third Embodiment)

The ash tin manufacturing facility 102 shown in Fig. 3 will be described. With regard to the equipment constituting the ashless coal manufacturing facility 102, the same components as those of the equipment constituting the ashless coal manufacturing facility 100 shown in Fig. 1 are denoted by the same reference numerals.

In the present embodiment, the heat energy held by the vapor-state solvent generated in the extraction step (extraction tank 8) is used for heating hot oil (thermal oil) in the third heat exchanger 20. [ Structurally, the vaporized solvent generated in the extraction process (extraction tank 8) is sent to the third heat exchanger 20 via the pipe 22, where the hot oil (thermal oil) is heated have.

In the process for producing ashless coal, it is necessary to set the coal and the slurry of the solvent to a high temperature state of, for example, 250 DEG C or more. Hot oil (thermal oil) is one of the heating media that heats slurry of coal and solvent. For example, in the case of using the thin film distillation method in the step of acquiring the unburned carbon, hot oil (thermal oil) is used for heating the thin film distillation tank. The hot oil (heat medium oil) is heated to, for example, 280 to 350 캜 in the third heat exchanger 20. Conventionally, hot oil (thermal oil) is heated by an electric heater.

According to the above configuration, the thermal energy held by the solvent in the vapor state generated in the extraction step (extraction tank 8) can be reduced by at least one step (for example, It is not necessary to introduce an electric heater by using the heating oil (heating oil oil) used as a heating source. Even if the introduction of the electric heater does not become zero, the amount of the electric heater to be introduced is reliably reduced. Therefore, the installation cost and the running cost of the electric heater can be reduced.

Further, in the present embodiment, among the thermal energy held in the vapor state solvent generated in the extraction step (extraction tank 8), the remaining heat energy used for heating the hot oil (thermal oil) Is used as a heat source for heating the solvent in the separating step (second gravitational forceps 10) in the separating step (17). According to this configuration, the second gravitational forceps 10 can be effectively kept warm (heated), and as a result, the heat energy to be newly introduced from outside the process system (energy for heating) can be reduced.

In the present embodiment, the thermal energy remaining in the steam is then recovered by the heat recovery boiler 18 as heat energy remaining thereafter. According to this configuration, it is possible to minimize the disposal arrangement.

&Lt; Specific reduction amount of heat energy newly introduced from the outside of the process >

Here, in the ashless carbon production equipment 102 illustrated in Figure 3, in the third heat exchanger 20, the hot oil (thermal oil) was heated to 300 ℃ to ^{320 ℃ (1.25 × 10 3 kcal} / ton- coal (2.37 x 10 &lt; ³ &gt; kcal / ton-coal throughput) of the solvent in the first heat exchanger (17). That is, the heat quantity of 1.25 × 10 ³ kcal / ton-coal throughput in the third heat exchanger 20 and the heat quantity of 2.37 × 10 ³ kcal / ton-coal throughput in the first heat exchanger 17 were measured in the process (Equipment). In addition, the heat of 0.96 × 10 ³ kcal / ton-coal throughput can be recovered in the batch recovery boiler 18 to produce steam.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, but can be variously modified within the scope of the claims.

The present application is based on Japanese Patent Application (Patent Application No. 2013-267438) filed on December 25, 2013, the content of which is incorporated herein by reference.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to reduce the running cost and effectively manufacture the ashless coal at low cost by effectively utilizing the arrangement of the ashless coal manufacturing facility.

1: Coal Hopper
2: solvent tank
3: Slurry preparation
4, 6, 16: Feed pump
5: Dehydration tank
7: Preheater
8: Extraction tank
9: First gravity sedimentation emphasis
10: Second gravity sedimentation emphasis
11, 12: a flasher (solvent separator)
13, 17: Heat exchanger
14: Slurry dewatering heater
18, 19: Sequence recovery boiler
100: Non-ferrous production facility

Claims (12)

A slurry preparing step of preparing a slurry by mixing coal and a solvent,
An extraction step of heating the slurry obtained in the slurry preparing step to extract a soluble coal component in the solvent,
A separation step of separating the slurry obtained in the extraction step into a solution containing a coal component soluble in the solvent and a solid concentrate in which a coal component insoluble in the solvent is concentrated;
And an unburned carbon obtaining step of volatilizing and separating the solvent from the solution separated in the separating step to obtain an unburned carbon,
Wherein the heat energy held by the solvent in the vapor state generated in at least one of the extraction step and the non-recycle step is used as a heat source in at least one step of producing the ashless carbonaceous material, And recovering heat in the batch recovery boiler as the heat energy to be recovered. The method according to claim 1,
Wherein the heat energy held by the solvent in the vapor state generated in the extraction step is used as a heat source for heating the solvent in the separation step. 3. The method of claim 2,
The heat energy retained by the solvent in the vapor state generated in the extraction step is used as a heat source for heating the solvent in the separation step and then the remaining heat energy is recovered as heat energy in the steam recovery heat recovery boiler By weight. 4. The method according to any one of claims 1 to 3,
Wherein the heat energy held by the solvent in the vapor state generated in the extraction step is used as a heat source for heating the slurry in the extraction step. 4. The method according to any one of claims 1 to 3,
Wherein the heat energy retained by the solvent in the vapor state generated in the ash recovery step is used as a heat source for heating the slurry in the extraction step. 6. The method of claim 5,
A slurry dewatering step of dewatering the slurry obtained in the slurry preparing step by preliminary heating is provided between the slurry preparing step and the extraction step,
The thermal energy retained by the solvent in the vapor state generated in the ashless coal obtaining step is used as a heat source for heating the slurry in the extraction step and the remaining thermal energy is used for the slurry dewatering in the slurry dewatering step As a heat source for the ashless coal. The method according to claim 1,
Characterized in that the thermal energy held by the solvent in the steam state generated in the extraction step is recovered by heat in an arrangement recovery boiler as thermal energy possessed by steam. The method according to claim 1,
Wherein the thermal energy retained by the solvent in the vapor state generated in the non-recycle step is heat-recovered in the arrangement recovery boiler as thermal energy possessed by the water vapor. The method according to claim 1,
Further comprising a step of obtaining by-product carbon by evaporating and separating the solvent from the solid concentrate separated in the separation step,
Wherein the thermal energy held by the solvent in the vapor state generated in the by-product burning step is heat-recovered in the arrangement recovery boiler as thermal energy possessed by the steam. The method according to claim 1,
Characterized in that the thermal energy held by the solvent in the steam state generated in the extraction step is used for heating the heat medium oil used as a heating source in at least one step of producing the ashless coal . 11. The method of claim 10,
Characterized in that the remaining heat energy is used as a heat source for heating the solvent in the separation step after the thermal energy held by the solvent in the vapor state generated in the extraction step is used for heating the heat medium oil, A method of manufacturing an ashless carbon. 12. The method of claim 11,
The remaining heat energy is used as a heat source for heating the solvent in the separation step after the thermal energy held by the solvent in the vapor state generated in the extraction step is used for heating the heat medium oil, And recovering heat from the batch recovery boiler as heat energy of the steam.

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