JP2005206695A - Apparatus and method for producing solid fuel from raw-rank coal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method for producing a solid fuel from raw-rank coal, whereby the productivity [throughput/(time×consumed energy)] of the solid fuel can be improved. <P>SOLUTION: There are provided [1] the solid fuel production apparatus comprising a mixing tank 1 for making a slurry by mixing a mixed oil containing a heavy oil component and a solvent oil component with low-rank coal, an evaporator 7 for evaporating water from the slurry, and a solid/liquid separator for effecting the solid/liquid separation of the slurry subjected to the evaporation, (a) wherein the mixing tank 1 has a raw slurry heating means (e.g, heat exchanger 4) for heating the raw material slurry or (b) wherein the evaporator 7 has the first-stage evaporator for heating the raw material slurry and the second-stage evaporator for further subjecting the heated slurry to heating and/or pressure reduction, [2] the production method for the solid fuel comprising heating the raw material slurry, and the like. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention belongs to a technical field related to a solid fuel production apparatus and production method using low-grade coal as a raw material.

  As a conventional technique for producing a solid fuel using low-grade coal as a raw material, there is a method for producing a solid fuel described in JP-A-7-233383 (Patent Document 1). In the method for producing a solid fuel described in this publication, a mixed oil containing a heavy oil and a solvent oil is mixed with porous coal to obtain a raw material slurry, and this slurry is heated to advance dehydration of the porous coal. A solid fuel production method is characterized in that a mixed oil containing a heavy oil and a solvent oil is contained in the pores of porous charcoal, and then this slurry is subjected to solid-liquid separation. Here, the porous coal corresponds to low grade coal.

  According to the method for producing a solid fuel described in the above publication, it is possible to obtain a solid fuel that is dehydrated, has a low pyrophoric property, is excellent in transportability and storage property, and has a high calorie content.

  That is, since porous coal (low-grade coal) contains a large amount of moisture, the transportation cost is expensive due to the same aspect as transporting moisture, and in this respect, the transportability is poor, and , Calories are reduced by the amount of water content. Therefore, it is desired to dehydrate the porous charcoal. However, if this dehydration is performed by a dry evaporation type dehydration method such as a tubular dryer, the oxygen to the active sites existing in the pores of the dehydrated porous coal is reduced. There is a risk of spontaneous ignition due to adsorption and oxidation reactions.

  On the other hand, in the method for producing a solid fuel described in the above publication, the inside of the pores of the porous coal is heated by heating the raw material slurry (a mixture of the mixed oil containing the heavy oil and the solvent oil and the porous coal). As the water vapor evaporates, the pores are covered with the mixed oil containing the heavy oil, and finally the mixed oil, particularly the heavy oil, preferentially fills the pores. Oxygen adsorption and oxidation reaction on active sites present in the pores are suppressed, and thus spontaneous ignition is suppressed. Moreover, while dehydrating by the said heating, a calorie becomes high by this dehydration and oil filling in the said pore. Accordingly, it is possible to obtain a solid fuel that is dehydrated, has low pyrophoric properties, is excellent in transportability and storage properties, and is highly caloric.

Regarding the apparatus for producing the solid fuel as described above, the above publication (Japanese Patent Laid-Open No. 7-233383) discloses that a mixed oil containing a heavy oil and a solvent oil is mixed with porous coal to obtain a raw material slurry. An apparatus for producing a solid fuel, comprising: a mixing tank to be formed; an evaporator for heating the raw slurry to remove water vapor; and a solid-liquid separator for solid-liquid separation of the heated treated slurry. Has been described. Here, the porous coal corresponds to low grade coal.
JP 7-233383 A

  The solid fuel production apparatus described in the above publication is a basic apparatus for producing the above solid fuel. When such an apparatus is used, in order to maintain a slurry state in a mixing tank and an evaporator, normally, while stirring with a stirrer, the slurry is circulated by a slurry pump to be in a turbulent state, and coal is deposited by sedimentation. And keep the slurry state. The slurry must have good fluidity.

  For this reason, when making a raw material slurry by mixing a mixed oil containing heavy oil and solvent oil and raw coal (low-grade coal) in a mixing tank, the mixing ratio of the raw coal to this mixed oil is limited. The That is, the ratio of the mixed oil to the raw material coal to be mixed needs to be a value (amount of mixed oil / amount of raw material coal) such that a raw material slurry having good fluidity can be obtained. Here, weight (S) is used as the amount of the mixed oil. The amount of raw material coal is the weight (C) based on dry / anhydrous standards. That is, the raw coal (low-grade coal) mixed with the mixed oil contains moisture, but the weight of the coal (dry / anhydrous coal) when the raw coal is dried to be in an anhydrous coal state (C) Is used.

Thus, the ratio of the mixed oil to the raw material coal to be mixed (hereinafter also referred to as S / C) is set to a value (hereinafter referred to as [S / C] _UL or higher) at which a raw material slurry having good fluidity can be obtained. It is necessary to say). For this reason, under the condition where the plant size is constant, the productivity (production amount / time) of the solid fuel is limited by the S / C. If the S / C is simply decreased to improve the productivity, a raw material slurry having good fluidity cannot be obtained, the plant cannot be operated, and the productivity cannot be improved.

  If a raw material slurry having good fluidity can be obtained even if the S / C is lowered, productivity can be improved. That is, if the S / C can be lowered while ensuring good fluidity, the productivity (production amount / time) of the solid fuel can be improved. Alternatively, the plant size can be reduced under a constant productivity condition.

  In the solid fuel production apparatus described in the above publication, the raw slurry is heated in an evaporator to dehydrate the low-grade coal in the raw slurry. At this time, the heating temperature needs to be higher than the boiling point of water in order to increase the dehydration rate. For example, in order to evaporate (dehydrate) 96% of the water contained in the low-grade coal, the temperature needs to be 5 ° C. higher than the boiling point of water. That is, a superheat temperature of 5 ° C. is necessary. It is necessary to raise the temperature excessively in this way because the moisture of coal is water that has a small interaction with the coal surface (hereinafter referred to as free water), water that exists in the pores of coal and has a strong surface tension ( (Hereinafter referred to as pore water) and water strongly associated with functional groups on the coal surface (hereinafter referred to as crystallization water). Among these, free water evaporates at almost the same boiling point as single water, Pore water and crystal water have a higher boiling point than single water, and this is mainly due to the fact that excessive energy is required for evaporation.

  Heating of the raw material slurry in the evaporator is performed by a heat exchanger provided in the middle of the raw material slurry supply flow path from the mixing tank to the evaporator, and steam generated in the evaporator is used as a heat source for the heat exchanger. The one whose temperature has been raised at is used. At this time, the lower the temperature of the water vapor sucked by the compressor, the lower the operating power of the compressor, and thus the energy required for operating the evaporator.

  Therefore, if a high level of dehydration rate can be secured even if the heating temperature in the evaporator is lowered (a high level of dehydration rate can be secured and the heating temperature in the evaporator can be lowered), a compressor can be used. The temperature of the water vapor to be sucked can be lowered, so that the driving power of the compressor can be lowered, and consequently the energy required for the operation of the evaporator can be reduced. In addition, the required energy can be reduced by lowering the heating temperature in the evaporator itself. As a result of the reduction of the required energy, the productivity (production amount / input energy) of the solid fuel can be improved.

  The present invention has been made paying attention to such circumstances, and an object of the present invention is a solid fuel production apparatus and production method using low-grade coal as a raw material. (Time / input energy)] is intended to provide a solid fuel production apparatus and method. More specifically, a raw material slurry having good fluidity can be obtained even if the S / C (ratio of the mixed oil to the raw material coal) is reduced, and the S / C can be obtained without hindering the fluidity of the raw material slurry. The solid fuel production apparatus and production method that can improve the productivity of solid fuel, and the high dehydration rate can be secured even if the heating temperature in the evaporator is lowered. Therefore, an object of the present invention is to provide a solid fuel production apparatus and a production method capable of lowering the heating temperature in the evaporator without impairing the rate, and thus improving the productivity of the solid fuel.

  In order to achieve the above object, the present inventors have intensively studied, and as a result, completed the present invention. According to the present invention, the above object can be achieved.

  The present invention, which has been completed in this way and has achieved the above object, relates to a solid fuel production apparatus and production method using low-grade coal as a raw material. A fuel production apparatus (solid fuel production apparatus according to first to fifth inventions), a solid fuel production method according to claims 6 to 7 (solid fuel production method according to sixth to seventh inventions), The configuration is as follows.

  That is, the solid fuel manufacturing apparatus according to claim 1 includes a mixing tank for mixing a mixed oil containing a heavy oil and a solvent oil with a low-grade coal to form a raw slurry, and an evaporator for performing a water evaporation process on the raw slurry. And a solid-liquid separator for solid-liquid separation of the moisture-evaporated slurry, wherein the mixing tank has a raw slurry heating means for heating the raw slurry. An apparatus for producing solid fuel [first invention].

  The solid fuel manufacturing apparatus according to claim 2, wherein the mixing tank has a slurry circulation passage through which a raw material slurry is introduced into the upper part of the mixing tank through a slurry pump, and the raw material slurry heating means is The solid fuel production apparatus according to claim 1, wherein the solid fuel production apparatus is provided in the slurry circulation passage [second invention].

  The solid fuel production apparatus according to claim 3 is the solid fuel production apparatus according to claim 1 or 2, wherein a heat exchanger is used as the raw material slurry heating means [third invention].

  The solid fuel production apparatus according to claim 4 is the solid fuel production apparatus according to any one of claims 1 to 3, wherein water vapor generated in the evaporator is used as a heat source of the raw slurry heating means. 4 invention].

  The apparatus for producing a solid fuel according to claim 5 is a mixing tank for mixing a mixed oil containing a heavy oil component and a solvent oil component with low-grade coal to form a raw slurry, an evaporator for performing a water evaporation treatment on the raw slurry, An apparatus for producing a solid fuel having a solid-liquid separator for solid-liquid separating the water-evaporated slurry, the first stage evaporator for heating the raw slurry as the evaporator, and the heated And a second stage evaporator for further heating and / or depressurizing the slurry (5th invention).

  In the method for producing a solid fuel according to claim 6, a mixed oil containing a heavy oil and a solvent oil is mixed with a low-grade coal to form a raw slurry, and the raw slurry is heated. This is a method for producing a solid fuel, characterized by evaporating and separating the liquid-evaporated slurry by solid-liquid separation [Sixth Invention].

  In the method for producing a solid fuel according to claim 7, a mixed oil containing a heavy oil component and a solvent oil component is mixed with low-grade coal to form a raw material slurry, the raw material slurry is subjected to a water evaporation process, and the water evaporation process is performed. A method for producing a solid fuel for solid-liquid separation of a slurry, wherein the raw slurry is first heated to evaporate free water of coal in the raw slurry as a water evaporation process of the raw slurry. The solid slurry is subjected to a second stage water evaporation treatment in which the raw material slurry is further heated and / or decompressed to evaporate pore water and crystallization water of coal in the raw material slurry. A fuel production method [seventh invention].

  According to the solid fuel manufacturing apparatus according to the first to fourth inventions of the present invention, a raw material slurry having good fluidity can be obtained even if the S / C (ratio of the mixed oil to the raw material coal) is reduced. S / C can be reduced without hindering the fluidity of the liquid. As a result, productivity of solid fuel [production amount / (time / input energy)] can be improved. Alternatively, the plant size can be reduced under constant productivity conditions.

  According to the solid fuel production apparatus of the fifth aspect of the present invention, a high level of dehydration rate can be secured even if the heating temperature in the evaporator is lowered, and heating in the evaporator is performed without causing any problem in the dehydration rate. The temperature can be lowered, so that the energy required for the operation of the evaporator can be reduced. As a result, productivity of solid fuel [production amount / (time / input energy)] can be improved.

  According to the method for producing a solid fuel according to the sixth aspect of the present invention, a raw material slurry having good fluidity can be obtained even if the S / C is reduced, and without affecting the fluidity of the raw material slurry. / C can be reduced. As a result, productivity of solid fuel [production amount / (time / input energy)] can be improved. Alternatively, the plant size can be reduced under constant productivity conditions.

  According to the method for producing a solid fuel according to the seventh aspect of the present invention, a high level of dehydration rate can be secured even when the heating temperature in the evaporator is lowered, and heating in the evaporator is performed without causing any problem in the dehydration rate. The temperature can be lowered, so that the energy required for the operation of the evaporator can be reduced. As a result, productivity of solid fuel [production amount / (time / input energy)] can be improved.

  The solid fuel manufacturing apparatus according to the first aspect of the present invention, as described above, mixes a mixed oil containing heavy oil and solvent oil with low-grade coal to form a raw slurry, and this raw slurry A solid fuel manufacturing apparatus having an evaporator for performing a water evaporation process and a solid-liquid separator for solid-liquid separating the slurry subjected to the water evaporation process, wherein the mixing tank has a raw material slurry heating means for heating the raw material slurry. It is the manufacturing apparatus of the solid fuel characterized by having.

  Thereby, the raw material slurry heating means can heat the raw material slurry. When the raw slurry is heated, the fluidity of the raw slurry is improved.

  Therefore, according to the above apparatus (the solid fuel production apparatus according to the first invention), a raw material slurry having good fluidity can be obtained even if the S / C (the ratio of the mixed oil to the raw material coal) is reduced. S / C can be lowered without hindering the fluidity of the slurry. As a result, productivity [production amount / (time / input energy)] is improved. Alternatively, the plant size can be reduced under constant productivity conditions.

  The raw slurry heating means is provided as follows, for example. The mixing tank has a slurry circulation channel for introducing the raw material slurry from the lower part thereof to the upper part of the mixing tank via a slurry pump, and a raw material slurry heating means is provided in the slurry circulation channel [second invention]. When the raw material slurry heating means is provided in this way, the heat exchange efficiency is good, the raw material slurry is easily heated, and the heating efficiency is good. That is, the raw material slurry temperature can be raised in a short time with less energy. On the other hand, when the raw material slurry heating means is provided around the mixing tank, the heating efficiency is small.

  As the raw material slurry heating means, for example, a heat exchanger is used [third invention]. When a heat exchanger is used, the heat exchange efficiency is good and the heating efficiency is good.

  As a heat source for the raw slurry heating means, it is desirable to use water vapor generated in the evaporator of the above apparatus [fourth invention]. This is because the water vapor generated in the evaporator can be used effectively and energy is saved.

  The solid fuel manufacturing apparatus according to the fifth aspect of the present invention, as described above, mixes a mixed oil containing heavy oil and solvent oil with low-grade coal to form a raw slurry, and this raw slurry An apparatus for producing a solid fuel, comprising: an evaporator that performs a water evaporation process; and a solid-liquid separator that performs solid-liquid separation on the slurry subjected to the water evaporation process, wherein the raw slurry is heated as the evaporator. An apparatus for producing a solid fuel, comprising: an eye evaporator; and a second stage evaporator for further heating and / or depressurizing the heated slurry.

  As mentioned above, the moisture of coal includes free water (water that has a small interaction with the coal surface), pore water (water that exists in the coal pore and has a strong surface tension), and crystal water (on the coal surface). In this, free water evaporates at a boiling point almost the same as that of single water, but pore water and crystal water have a boiling point higher than that of single water. Excess energy is required.

  Therefore, the first stage evaporator is used as an evaporator for evaporating free water, and the second stage evaporator is used as an evaporator for evaporating pore water and crystal water. That is, the first stage evaporator is heated to a temperature necessary for evaporating free water. Thereby, free water evaporates and pore water and crystal water remain. In the second stage evaporator, the remaining pore water and crystal water are heated to a temperature necessary for evaporating or reduced to a necessary pressure. Alternatively, the pressure is reduced while heating. Thereby, pore water and crystal water evaporate. As described above, the water evaporation of the raw slurry is performed. That is, the low-grade coal in the raw slurry is dehydrated. At this time, the same high level of dehydration rate as in the conventional case can be secured.

  The heating temperature in the first stage evaporator is lower than the heating temperature in the evaporator when there is only one evaporator as in the prior art. In the second stage evaporator, dehydration can be performed with appropriate energy without waste. Therefore, the heating temperature in the evaporator is lower than that in the conventional case in the entire evaporator.

  Therefore, even if the heating temperature in the evaporator is lowered, a high level of dehydration rate can be secured, and the heating temperature in the evaporator can be lowered without hindering the dehydration rate.

  For this reason, the energy required for the operation of the evaporator can be reduced. Details will be described below.

  As described above, the heating of the raw material slurry in the evaporator is performed by a heat exchanger provided in the middle of the raw material slurry supply flow path from the mixing tank to the evaporator, and the heat source of the heat exchanger is generated by the evaporator. What heated up the steam with the compressor is used. As the water vapor, water vapor generated in the first stage evaporator is used. That is, as the heat source of the heat exchanger, water vapor generated in the first stage evaporator is heated with a compressor. At this time, the temperature of water vapor generated in the first stage evaporator is lower than the temperature of water vapor generated in the evaporator when there is one evaporator as in the prior art. Therefore, the temperature of the water vapor sucked by the compressor is low, and the operating power of the compressor can be lowered. As a result, the energy required for the operation of the evaporator can be reduced.

  In addition, the required energy can be reduced by lowering the heating temperature in the evaporator itself.

  By reducing the required energy as described above, the productivity [production amount / (time / input energy)] of the solid fuel can be improved.

  In the solid fuel production apparatus according to the fifth aspect of the present invention, when the mixing tank has raw material slurry heating means for heating the raw material slurry, that is, the apparatus according to the fifth aspect of the present invention and the first aspect of the present invention. In the case of the device combined with the device according to the invention, the function and effect of the first invention can be achieved in addition to the function and effect of the fifth invention.

  In the present invention, the low-grade coal is a coal that contains a large amount of moisture and is desired to be dehydrated as described above. Examples of such low-grade coal include lignite, lignite, subbituminous coal, and the like. For example, lignite coal includes Victoria coal, North Dakota coal, Belga coal, etc., and subbituminous coal includes West Bango coal, Binungan coal, and the like. The low-grade coal is not limited to those exemplified above, and any coal containing a large amount of water and desired to be dehydrated is included in the low-grade coal according to the present invention.

  The heavy oil component is a heavy component or an oil containing the heavy component that does not substantially exhibit a vapor pressure even at, for example, 400 ° C., such as a vacuum residue oil.

  The water evaporation process of the raw slurry is a process of dehydrating low-grade coal in the raw slurry. That is, it is a process of evaporating the moisture contained in the low-grade coal and removing the water vapor generated thereby.

  When the raw material slurry is heated in the evaporator by a heat exchanger provided in the middle of the raw material slurry supply flow path from the mixing tank to the evaporator, this heat exchanger is not the raw material slurry heating means according to the present invention. That is, the heating of the raw material slurry by the heat exchanger is performed for the water evaporation process of the raw material slurry, and this is not included in heating the raw material slurry by the raw material slurry heating means according to the present invention. The heating of the raw material slurry by the raw material slurry heating means according to the present invention is performed in order to increase the temperature of the raw material slurry in relation to the fluidity of the raw material slurry in the mixing tank and the slurry circulation passage.

  The mixing tank is not particularly limited, and various types can be used, but an axial flow type stirrer or the like is usually used. The evaporator is not particularly limited, and various types can be used. For example, an evaporator such as a flash evaporation type, a coil type, or a forced circulation type vertical tube type can be used, but usually a heat exchanger. Use an evaporator such as a forced circulation type.

  The solid-liquid separation device is not particularly limited, and various devices can be used. For example, a centrifuge, a press, a sedimentation tank, a filter, or the like can be used. Use.

  The slurry is dehydrated by the evaporator, and this slurry (dehydrated slurry) is solid-liquid separated by the solid-liquid separator to obtain a solid component and a liquid component. As for this solid content, the oil content remaining in the solid content is recovered in the final drying section, and the solid content can be used as a powdered solid fuel. Alternatively, after the final drying section, it is molded in the molding section to become a molded solid fuel.

  In the method for producing a solid fuel according to the sixth aspect of the present invention, as described above, a mixed oil containing heavy oil and solvent oil is mixed with low-grade coal to form a raw slurry, and this raw slurry is heated, Thereafter, the raw material slurry is subjected to a water evaporation process, and the slurry subjected to the water evaporation process is subjected to solid-liquid separation. By heating the raw material slurry, the fluidity of the raw material slurry is improved.

  Therefore, according to the above method (the method for producing a solid fuel according to the sixth invention), a raw material slurry having good fluidity can be obtained even when the S / C (the ratio of the mixed oil to the raw material coal) is reduced. S / C can be lowered without hindering the fluidity of the slurry. As a result, productivity [production amount / (time / input energy)] is improved. Alternatively, the plant size can be reduced under constant productivity conditions.

  As described above, the method for producing a solid fuel according to the seventh aspect of the present invention mixes a mixed oil containing a heavy oil and a solvent oil with a low-grade coal to form a raw slurry, and the raw slurry is subjected to a water evaporation process. A method for producing a solid fuel for solid-liquid separation of the water-evaporated slurry, wherein the raw material slurry is first heated to obtain free coal water in the raw material slurry. The first stage moisture evaporation treatment is performed, and then the raw slurry is further heated and / or reduced in pressure to evaporate coal pore water and crystal water in the raw slurry. A method for producing a solid fuel.

  As mentioned above, the moisture of coal includes free water (water that has a small interaction with the coal surface), pore water (water that exists in the coal pore and has a strong surface tension), and crystal water (on the coal surface). In this, free water evaporates at a boiling point almost the same as that of single water, but pore water and crystal water have a boiling point higher than that of single water. Excess energy is required. Therefore, the heating temperature in the first stage water evaporation process is lower than the heating temperature in the evaporator when there is one evaporator as in the prior art. In the second stage water evaporation process, dehydration can be performed with appropriate energy without waste. Therefore, the heating temperature in the evaporator is lower than that in the conventional case in the entire evaporator.

  Therefore, according to the above method (the method for producing a solid fuel according to the seventh aspect of the present invention), a high level of dehydration rate can be secured even if the heating temperature in the evaporator is lowered, and the dehydration rate is hindered. In addition, the heating temperature in the evaporator can be lowered. For this reason, the energy required for the operation of the evaporator can be reduced. By reducing the required energy as described above, the productivity [production amount / (time / input energy)] of the solid fuel can be improved.

  Embodiments 1 to 3 of the present invention are shown in FIGS. An example for comparison is shown in FIG.

  In the case of the embodiment of FIG. 1 (embodiment for comparison), a mixing tank 1 that mixes a mixed oil containing heavy oil and solvent oil with low-grade coal to form a raw slurry, and this raw slurry is subjected to moisture evaporation treatment And a solid-liquid separator (not shown) for solid-liquid separation of the water-evaporated slurry. Here, the mixing tank 1 has slurry circulation channels 2 and 5 for introducing the raw material slurry from the lower part thereof to the upper part of the mixing tank 1 via the slurry pump 3. The evaporator 7 has slurry circulation passages 11 and 13 to 14 for introducing the slurry from the lower part thereof to the upper part of the evaporator 7 via the slurry pump 12. Between the mixing tank 1 and the evaporator 7, there is a raw material slurry supply channel 6. This raw material slurry supply channel 6 is branched from the slurry circulation channels 2 and 5.

  In the mixing tank 1, a mixed oil containing heavy oil and solvent oil and low-grade coal are mixed to make a raw slurry. This raw material slurry is introduced from the lower part of the mixing tank 1 through the slurry circulation passages 2 and 5 to the upper part of the mixing tank 1 via the slurry pump 3 and circulated. The raw material slurry is circulated and enters the slurry circulation flow paths 13 to 14 of the evaporator 7 through the raw material slurry supply flow path 6 branched from the slurry circulation flow paths 2 and 5, and enters the evaporator 7 through this. . At this time, the raw material slurry is heated by the heat exchanger 15, further heated by the heat exchanger 21, and enters the evaporator 7. Thereby, the water | moisture-content evaporation process of a raw material slurry is made | formed. That is, moisture contained in the low-grade coal in the raw slurry is evaporated and dehydrated. At the same time, mixed oil is contained in the pores of the low-grade coal.

  The water vapor generated by the evaporation is introduced from the evaporator 7 through the flow path 8 into the heat exchanger 21 and used as a heat source (heating medium) of the heat exchanger 21, and further through the flow paths 9 to 10. 15 and used as a heat source (heating medium) of the heat exchanger 15.

  A dehydrated slurry is obtained by the moisture evaporation process (dehydration process). The dehydrated slurry enters the solid-liquid separator through the dehydrated slurry supply flow path 22 branched from the slurry circulation flow paths 11 and 13 to 14, and is separated into solid and liquid to obtain a solid content and a liquid content. As for this solid content, the oil content remaining in the solid content is recovered in the final drying section, and the solid content can be used as a powdered solid fuel. Alternatively, after the final drying section, it is molded in the molding section to become a molded solid fuel.

  In the case of the apparatus of the embodiment shown in FIG. 1, the raw material slurry is heated by the heat exchanger 15 as described above, further heated by the heat exchanger 21, and enters the evaporator 7. It is not the raw material slurry heating means according to the invention. That is, the raw material slurry is heated by the heat exchangers 15 and 21, and the heating of the raw material slurry by the heat exchangers 15 and 21 is performed for moisture evaporation treatment (dehydration treatment) of the raw material slurry. Is not included in heating the raw slurry by the raw slurry heating means according to the present invention. The heating of the raw material slurry by the raw material slurry heating means according to the present invention is performed in order to increase the temperature of the raw material slurry in relation to the fluidity of the raw material slurry in the mixing tank 1 and its slurry circulation channels 2 and 5. is there.

  In the case of the embodiment shown in FIG. 2 (the apparatus of Embodiment 1), a mixing tank 1 that mixes a mixed oil containing a heavy oil and a solvent oil with low-grade coal to form a raw slurry, and this raw slurry is subjected to moisture evaporation treatment. It has an evaporator 7 and a solid-liquid separator (not shown) for solid-liquid separation of the water-evaporated slurry, and the mixing tank 1 further has a raw slurry heating means for heating the raw slurry. Here, the mixing tank 1 has slurry circulation channels 2 and 5 for introducing the raw material slurry from the lower part thereof to the upper part of the mixing tank 1 via the slurry pump 3. The evaporator 7 has slurry circulation channels 11 and 13 to 14 for introducing the slurry from the lower part thereof to the upper part of the evaporator 7 via the slurry pump 12. Between the mixing tank 1 and the evaporator 7, there is a raw material slurry supply channel 6. This raw material slurry supply channel 6 is branched from the slurry circulation channels 2 and 5.

  As the raw material slurry heating means, a heat exchanger 4 is used and provided in the slurry circulation flow path 5. As a heat source (heating medium) of the heat exchanger 4, steam generated in the evaporator 7 is used.

  In the mixing tank 1, a mixed oil containing heavy oil and solvent oil and low-grade coal are mixed to make a raw slurry. This raw material slurry is introduced from the lower part of the mixing tank 1 through the slurry circulation passages 2 and 5 to the upper part of the mixing tank 1 via the slurry pump 3 and circulated. At this time, the raw slurry is heated by the heat exchanger 4.

  In this way, the raw slurry is circulated and heated. Then, this raw material slurry enters the slurry circulation flow paths 13 to 14 of the evaporator 7 through the raw material slurry supply flow path 6 branched from the slurry circulation flow paths 2 and 5, and enters the evaporator 7 through this. At this time, the raw material slurry is heated by the heat exchanger 21 and enters the evaporator 7. Thereby, the water | moisture-content evaporation process of a raw material slurry is made | formed. That is, moisture contained in the low-grade coal in the raw slurry is evaporated and dehydrated. At the same time, mixed oil is contained in the pores of the low-grade coal.

  The water vapor generated by the evaporation passes from the evaporator 7 through the compressor 71, is introduced into the heat exchanger 21 through the flow path 8, and is used as a heat source (heating medium) of the heat exchanger 21. 10 is introduced into the heat exchanger 4 and used as a heat source (heating medium) of the heat exchanger 4.

  A dehydrated slurry is obtained by the moisture evaporation process (dehydration process). The dehydrated slurry enters the solid-liquid separator through the dehydrated slurry supply flow path 22 branched from the slurry circulation flow paths 11 and 13 to 14, and is separated into solid and liquid to obtain a solid content and a liquid content. As for this solid content, the oil content remaining in the solid content is recovered in the final drying section, and the solid content can be used as a powdered solid fuel. Alternatively, after the final drying section, it is molded in the molding section to become a molded solid fuel.

  In the case of the apparatus of the embodiment of FIG. 2 (apparatus of the embodiment 1), the heat exchanger 4 is provided in the slurry circulation passage 5 as the raw material slurry heating means as described above, and the slurry circulation flow is provided by this heat exchanger 4. Since the raw material slurry circulating in the path can be heated, the S / C (with respect to the raw material coal) when making the raw material slurry by mixing the mixed oil containing heavy oil and solvent oil and the low grade coal in the mixing tank 1 The fluidity of the raw slurry can be improved under a condition where the ratio of the mixed oil) is constant, and the S / C can be reduced under the condition where the fluidity of the raw slurry is constant. Therefore, according to the said apparatus, even if it reduces S / C, the raw material slurry which has favorable fluidity | liquidity is obtained, and S / C can be reduced, without causing trouble in the fluidity | liquidity of a raw material slurry. As a result, productivity of solid fuel [production amount / (time / input energy)] can be improved. Alternatively, the plant size can be reduced under constant productivity conditions.

  In the case of the embodiment of FIG. 3 (the apparatus of Embodiment 2), a mixing tank 1 that mixes a mixed oil containing heavy oil and solvent oil with low-grade coal to form a raw slurry, and this raw slurry is heated to A first-stage evaporator 7A for performing first-stage water evaporation, a second-stage evaporator 7B for further heating and / or depressurizing the heated slurry, and a second-stage water evaporation process; A solid-liquid separator (not shown) for solid-liquid separation of the water-evaporated slurry.

  Here, the mixing tank 1 has slurry circulation channels 2 and 5 for introducing the raw material slurry from the lower part thereof to the upper part of the mixing tank 1 via the slurry pump 3. The first stage evaporator 7A has slurry circulation passages 11 and 13 to 14 for introducing the slurry into the upper part of the evaporator 7A via the slurry pump 12 from the lower part. The second stage evaporator 7B has slurry circulation channels 56 and 58 for introducing the slurry from the lower part thereof to the upper part of the evaporator 7B via the slurry pump 57. There is a raw material slurry supply flow path 6 between the mixing tank 1 and the evaporator 7A. This raw material slurry supply channel 6 is branched from the slurry circulation channels 2 and 5. Between the evaporator 7A and the evaporator 7B, there are slurry supply channels 51 to 52. The slurry supply channels 51 to 52 are branched from the slurry circulation channels 11 and 13 to 14.

  In the mixing tank 1, a mixed oil containing heavy oil and solvent oil and low-grade coal are mixed to make a raw slurry. This raw material slurry is introduced from the lower part of the mixing tank 1 through the slurry circulation passages 2 and 5 to the upper part of the mixing tank 1 via the slurry pump 3 and circulated. The raw material slurry is circulated, passes through the raw material slurry supply flow channel 6 branched from the slurry circulation flow channels 2 and 5, and enters the slurry circulation flow channels 13 to 14 of the evaporator 7A, and passes through this to the evaporator 7A. enter. At this time, the raw slurry is heated by the heat exchanger 15, further heated by the heat exchanger 21, and enters the evaporator 7A. As a result, the first stage of water evaporation of the raw slurry is performed. That is, the free water in the water contained in the low-grade coal in the raw slurry is evaporated and dehydrated.

  The heated slurry, that is, the slurry subjected to the first stage water evaporation process, enters the evaporator 7B through the slurry supply channels 51 to 52 branched from the slurry circulation channels 11 and 13 to 14. At this time, the slurry is heated by the heat exchanger 62 and enters the evaporator 7B. In the evaporator 7B, the pressure may be reduced. Thereby, the water evaporation process of the 2nd step of a slurry is made. That is, pore water and crystal water in the water contained in the low-grade coal in the slurry are evaporated and dehydrated. In addition, mixed oil is also contained in the pores of the low-grade coal along with the above dehydration.

  The water vapor generated by the first stage water evaporation process passes from the evaporator 7A through the compressor 71, through the flow path 8, and is introduced into the heat exchanger 21, and is used as a heat source (heating medium) of the heat exchanger 21. Furthermore, it is introduced into the heat exchanger 15 through the flow paths 9 to 10 and used as a heat source (heating medium) of the heat exchanger 15.

  The water vapor generated by the second-stage water evaporation process passes from the evaporator 7B through the compressor 72, passes through the flow path 53, and is introduced into the heat exchanger 62, and is used as a heat source (heating medium) of the heat exchanger 62. Furthermore, it is introduced into the heat exchanger 15 through the flow paths 54 to 55 and 10 and used as a heat source (heating medium) of the heat exchanger 15.

  A dehydrated slurry is obtained by the water evaporation process (dehydration process) in the first and second stages. The dehydrated slurry enters the solid-liquid separator through the dehydrated slurry supply channel 59 branched from the slurry circulation channels 56 and 58, and is separated into solid and liquid to obtain a solid component and a liquid component. As for this solid content, the oil content remaining in the solid content is recovered in the final drying section, and the solid content can be used as a powdered solid fuel. Alternatively, after the final drying section, it is molded in the molding section to become a molded solid fuel.

  In the case of the apparatus of the embodiment in FIG. 3 (apparatus of the embodiment 2), as described above, the raw slurry is heated by the heat exchanger 15, further heated by the heat exchanger 21, and enters the evaporator 7A. After the first stage moisture evaporation treatment of the raw slurry, free water in the low-grade coal in the raw slurry is evaporated and dehydrated, and then this slurry is heated by the heat exchanger 62 and evaporated. Entering the vessel 7B, the second stage moisture evaporation treatment of the slurry is performed, and the pore water and the crystal water in the moisture contained in the low-grade coal in the slurry are evaporated and dehydrated. As described above, the low-grade coal in the raw slurry is dehydrated. At this time, the same high level of dehydration rate as in the conventional case can be secured.

  The water vapor generated by the first-stage water evaporation process is adiabatically compressed by the compressor, and then used as a heat source for the heat exchanger 21 and further used as a heat source for the heat exchanger 15. The water vapor generated by the second-stage water evaporation process is heated by the compressor, used as a heat source for the heat exchanger 62, and further used as a heat source for the heat exchanger 15. At this time, the temperature of the water vapor generated in the first stage water evaporation process is lower than the temperature of the water vapor generated in the water evaporation process when there is one evaporator as in the prior art. The temperature of the steam to be produced is low, the operating power of the compressor can be lowered, and consequently the energy required for the water evaporation treatment operation can be reduced. In addition, since it is possible to perform dehydration with appropriate energy without waste in the second stage evaporator, it is said that the temperature is higher than the temperature of water vapor generated in the water evaporation process when there is only one evaporator as in the prior art. There is nothing. Therefore, the heating temperature in the evaporator is lower than that in the conventional case in the entire evaporator.

  Therefore, the heating temperature in the water evaporation process can be lowered as a whole without causing an obstacle to the dehydration rate, and therefore the energy required for the water evaporation process operation can be reduced. As a result, productivity of solid fuel [production amount / (time / input energy)] can be improved.

  In the case of the embodiment shown in FIG. 4 (apparatus of Embodiment 3), a mixing tank 1 that mixes a mixed oil containing heavy oil and solvent oil with low-grade coal to form a raw slurry, and this raw slurry is heated to A first-stage evaporator 7A for performing first-stage water evaporation, a second-stage evaporator 7B for further heating and / or depressurizing the heated slurry, and a second-stage water evaporation process; A solid-liquid separator (not shown) for solid-liquid separation of the water-evaporated slurry, and further, the mixing tank 1 has a raw slurry heating means for heating the raw slurry.

  Here, the mixing tank 1 has slurry circulation channels 2 and 5 for introducing the raw material slurry from the lower part thereof to the upper part of the mixing tank 1 via the slurry pump 3. The first stage evaporator 7A has slurry circulation passages 11 and 13 to 14 for introducing the slurry into the upper part of the evaporator 7A via the slurry pump 12 from the lower part. The second stage evaporator 7B has slurry circulation channels 56 and 58 for introducing the slurry from the lower part thereof to the upper part of the evaporator 7B via the slurry pump 57. There is a raw material slurry supply flow path 6 between the mixing tank 1 and the evaporator 7A. This raw material slurry supply channel 6 is branched from the slurry circulation channels 2 and 5. Between the evaporator 7A and the evaporator 7B, there are slurry supply channels 51 to 52. The slurry supply channels 51 to 52 are branched from the slurry circulation channels 11 and 13 to 14.

  As the raw material slurry heating means, a heat exchanger 4 is used and provided in the slurry circulation flow path 5. As a heat source (heating medium) of the heat exchanger 4, water vapor generated in the evaporator 7A is used, or water vapor generated in the evaporator 7B is also used.

  In the mixing tank 1, a mixed oil containing heavy oil and solvent oil and low-grade coal are mixed to make a raw slurry. This raw material slurry is introduced from the lower part of the mixing tank 1 through the slurry circulation passages 2 and 5 to the upper part of the mixing tank 1 via the slurry pump 3 and circulated. At this time, the raw slurry is heated by the heat exchanger 4.

  In this way, the raw slurry is circulated and heated. And this raw material slurry enters the slurry circulation flow paths 13-14 of the evaporator 7A through the raw material slurry supply flow path 6 branched from the slurry circulation flow paths 2, 5, and enters the evaporator 7A through this. At this time, the raw slurry is heated by the heat exchanger 21 and enters the evaporator 7A. As a result, the first stage of water evaporation of the raw slurry is performed. That is, the free water in the water contained in the low-grade coal in the raw slurry is evaporated and dehydrated.

  The heated slurry, that is, the slurry subjected to the first stage water evaporation process, enters the evaporator 7B through the slurry supply channels 51 to 52 branched from the slurry circulation channels 11 and 13 to 14. At this time, the slurry is heated by the heat exchanger 62 and enters the evaporator 7B. In the evaporator 7B, the pressure may be reduced. Thereby, the water evaporation process of the 2nd step of a slurry is made. That is, pore water and crystal water in the water contained in the low-grade coal in the slurry are evaporated and dehydrated. In addition, mixed oil is also contained in the pores of the low-grade coal along with the above dehydration.

  The water vapor generated by the first stage water evaporation process passes from the evaporator 7A through the compressor 71, through the flow path 8, and is introduced into the heat exchanger 21, and is used as a heat source (heating medium) of the heat exchanger 21. Furthermore, it is introduced into the heat exchanger 4 through the flow paths 9 to 10 and used as a heat source (heating medium) of the heat exchanger 4.

  The water vapor generated by the second-stage water evaporation process passes from the evaporator 7B through the compressor 72, passes through the flow path 53, and is introduced into the heat exchanger 62, and is used as a heat source (heating medium) of the heat exchanger 62. Furthermore, it is introduced into the heat exchanger 4 through the flow paths 54 to 55 and 10 and used as a heat source (heating medium) of the heat exchanger 4.

  A dehydrated slurry is obtained by the water evaporation process (dehydration process) in the first and second stages. The dehydrated slurry enters the solid-liquid separator through the dehydrated slurry supply channel 59 branched from the slurry circulation channels 56 and 58, and is separated into solid and liquid to obtain a solid component and a liquid component. As for this solid content, the oil content remaining in the solid content is recovered in the final drying section, and the solid content can be used as a powdered solid fuel. Alternatively, after the final drying section, it is molded in the molding section to become a molded solid fuel.

  In the case of the apparatus of the embodiment of FIG. 4 (apparatus of the embodiment 3), as in the case of the apparatus of the embodiment of FIG. 2, even if the S / C (ratio of the mixed oil to the raw coal) is reduced, the flow is good Thus, the S / C can be reduced without hindering the fluidity of the raw material slurry. Further, as in the case of the apparatus of the embodiment of FIG. 3, the heating temperature in the water evaporation process can be lowered as a whole without hindering the dehydration rate, which is necessary for the water evaporation process operation. Energy can be reduced. Therefore, in the case of the apparatus of the embodiment of FIG. 4, the solid fuel productivity [production quantity / volume] is compared with the case of the apparatus of the embodiment of FIG. 2 and the case of the apparatus of the embodiment of FIG. (Time / input energy)] is greatly improved.

  Examples of the present invention will be described below. The present invention is not limited to this embodiment, and can be implemented with appropriate modifications within a range that can be adapted to the gist of the present invention, all of which are within the technical scope of the present invention. include.

[Example 1, Comparative Example 1]
A test apparatus having the same configuration as that of the apparatus of the above-described embodiment of FIG. 2 was used, and a solid fuel production operation was performed by changing S / C (ratio of mixed oil to raw coal) as a parameter.

  At this time, the low-grade coal of the raw material used was Indonesian Binungan Block 7 coal (hereinafter referred to as Binungan Block 7 coal) (hereinafter referred to as Binungan coal) having a water content of 25 mass% (weight%). As a mixed oil containing a heavy oil and a solvent oil mixed with the low-grade coal, a mixed oil obtained by mixing asphalt with kerosene was used. Here, kerosene belongs to solvent oil, and asphalt belongs to heavy oil. The amount of asphalt in the mixed oil was 0.5% by weight (mass%).

  The raw slurry obtained by mixing the low-grade coal and the mixed oil in a mixing tank was heated by a raw slurry heating means included in the mixing tank. For comparison, the operation was performed even when the raw slurry was not heated.

  As a result, when the raw material slurry is not heated, that is, when the raw material slurry temperature is normal temperature, the fluidity of the raw material slurry becomes poor at S / C = 1.5, and the lower part of the mixing tank and the slurry circulation channel are clogged. However, when the raw material slurry is heated to 80 ° C. by the raw material slurry heating means, the fluidity of the raw material slurry is good up to S / C = 1.3, no clogging occurs, and the stable raw material slurry can be adjusted. I found it possible.

  Therefore, when the raw material slurry is heated to 80 ° C., the S / C can be lowered to 1.3 without hindering the fluidity of the raw material slurry. As a result, productivity [production amount / (time / input) It has been confirmed that the energy)] can be improved, or that the plant size can be reduced under the condition of constant productivity.

[Example 2, Comparative Example 2]
A solid fuel production operation was performed using a test apparatus (hereinafter, an apparatus according to Example 2) having the same configuration as the apparatus of the embodiment of FIG. 3 described above. Further, a solid fuel production operation was performed using a test apparatus (hereinafter, an apparatus according to Comparative Example 2) having the same configuration as the apparatus of the embodiment of FIG. 1 described above.

  At this time, the low-grade coal used as a raw material was Binungan coal from Indonesia and had a moisture content of 25% by weight. As a mixed oil containing a heavy oil and a solvent oil mixed with the low-grade coal, a mixed oil obtained by mixing asphalt with kerosene was used. Here, the amount of asphalt in the mixed oil was set to 0.5% by weight.

  As a result, in the case of the apparatus according to the second embodiment, compared with the case of the apparatus according to the second comparative example, the operating power of the compressor when the steam generated in the evaporator is heated by the compressor and used as the heat source of the heat exchanger. Was able to be reduced. That is, after the raw slurry is heated in the first stage moisture evaporation process to evaporate free water in the moisture contained in the low-grade coal in the raw slurry, this slurry is then subjected to the second stage moisture evaporation process. When the pore water and the crystal water in the water contained in the low-grade coal in the slurry are evaporated, this second-stage water evaporation treatment is performed by a method in which the slurry is further heated to raise the temperature. On the other hand, the operating power of the compressor can be reduced by 15%, and 55% when reduced by the pressure reducing method.

It is a schematic diagram which shows the outline | summary of the apparatus of the example for a comparison with the example of embodiment of this invention. It is a schematic diagram which shows the outline | summary of the apparatus of Embodiment 1 of this invention. It is a schematic diagram which shows the outline | summary of the apparatus of Embodiment 2 of this invention. It is a schematic diagram which shows the outline | summary of the apparatus of Embodiment 3 of this invention.

Explanation of symbols

1--Mixing tank, 2,5--Slurry circulation channel, 3--Slurry pump, 4--Heat exchanger,
6--Raw material supply channel, 7--Evaporator, 7A--First stage evaporator, 7B--Second-stage evaporator, 8--Channel, 9,10--Channel, 11 , 13, 14--Slurry circulation channel, 12--Slurry pump, 15--Heat exchanger, 21--Heat exchanger, 22--Dehydrated slurry supply channel,
51,52--Slurry supply channel, 53,54,55--Channel, 56,58--Slurry circulation channel,
57--Slurry pump, 59--Dehydrated slurry supply channel, 62--Heat exchanger,
71,72--Compressor.

Claims (7)

  Mixing oil containing heavy oil and solvent oil is mixed with low-grade coal to make a raw slurry, an evaporator for performing a water evaporation treatment on the raw slurry, and a solid-liquid separation of the water evaporated slurry. A solid fuel manufacturing apparatus having a solid-liquid separator, wherein the mixing tank has a raw slurry heating means for heating the raw slurry.   The said mixing tank has a slurry circulation flow path which introduce | transduces raw material slurry into the upper part of the said mixing tank through the slurry pump from the lower part, The said raw material slurry heating means is provided in the said slurry circulation flow path. The manufacturing apparatus of solid fuel of description.   The solid fuel production apparatus according to claim 1 or 2, wherein a heat exchanger is used as the raw slurry heating means.   The apparatus for producing a solid fuel according to any one of claims 1 to 3, wherein water vapor generated in the evaporator is used as a heat source of the raw slurry heating means.   Mixing oil containing heavy oil and solvent oil is mixed with low-grade coal to make a raw slurry, an evaporator for performing a water evaporation treatment on the raw slurry, and a solid-liquid separation of the water evaporated slurry. An apparatus for producing a solid fuel having a solid-liquid separator, wherein the evaporator is a first stage evaporator for heating the raw slurry, and a second for further heating and / or depressurizing the heated slurry. An apparatus for producing solid fuel, comprising: a stage evaporator.   A mixed oil containing heavy oil and solvent oil is mixed with low-grade coal to form a raw slurry, and this raw slurry is heated, and then the raw slurry is subjected to moisture evaporation treatment. A method for producing a solid fuel, comprising solid-liquid separation. A method for producing a solid fuel in which a mixed oil containing heavy oil and solvent oil is mixed with low-grade coal to form a raw material slurry, the raw material slurry is subjected to moisture evaporation treatment, and the moisture evaporated slurry is subjected to solid-liquid separation. As the water evaporation process of the raw material slurry, first, the raw material slurry is first heated to evaporate free water of coal in the raw material slurry, and then the raw material slurry is further processed. A method for producing a solid fuel, characterized in that a second stage water evaporation treatment is performed by evaporating the pore water and crystallization water of coal in the raw slurry by heating and / or reducing pressure.

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