KR102291836B1 - Method for manufacturing ashless coal and apparatus for manufacturing ashless coal - Google Patents

Abstract

A method for producing ashless coal according to an aspect of the present invention includes a step of heating a mixture of coal, a radical stabilizer and a solvent, and a step of eluting a component soluble in the solvent from the coal in the slurry obtained in the heating step; A step of separating the slurry after elution in the elution step into a liquid component containing a solvent-soluble component and a solvent-insoluble component; and a step of evaporating a solvent from the liquid component separated in the separation step. The apparatus for producing ashless coal according to another aspect of the present invention includes a heating unit for heating a mixture of coal, a radical stabilizer and a solvent, and an elution unit for eluting a component soluble in the solvent from the coal in the slurry obtained by the heating unit. and a solid-liquid separation unit for separating the slurry after elution from the elution unit into a liquid component containing a solvent-soluble component and a solvent-insoluble component, and an evaporation separation unit for evaporating a solvent from the liquid component separated by the solid-liquid separation unit be prepared

Description

Method for manufacturing ashless coal and apparatus for manufacturing ashless coal

The present invention relates to a method for manufacturing ashless coal and an apparatus for manufacturing ashless coal.

BACKGROUND ART Coal is widely used as a fuel for thermal power generation and boilers, or as a raw material for chemical products. As one of environmental measures, the development of a technology for efficiently removing ash in coal is strongly desired. For example, in a high-efficiency combined cycle power generation system by combustion of a gas turbine, an attempt is made to use ashless coal (HPC) from which ash has been removed as a fuel to replace liquid fuel such as LNG. In addition, attempts have been made to use ashless coal as raw coal for coke for iron manufacture, such as coke for blast furnaces.

As a method for producing ashless coal, a method of separating a solution containing a coal component soluble in a solvent (hereinafter also referred to as a solvent soluble component) from a slurry using a gravitational sedimentation method has been proposed (for example, Japanese Patent Laid-Open Publication No. See publication 2005-120185). This method is equipped with the extraction process which heats the slurry obtained by the slurry preparation process which mixes coal and a solvent and prepares a slurry, and the slurry preparation process, and extracts a solvent soluble component. In addition, this method includes a separation step of separating a solution in which the solvent soluble component is dissolved from the slurry from which the solvent soluble component is extracted in the extraction step, and a process of obtaining ashless coal by separating the solvent from the solution separated in the separation step. be prepared

In addition, there is also proposed a method for producing ashless coal that can shorten the extraction time of solvent-soluble components compared to the conventional method for producing ashless coal (see Japanese Patent Application Laid-Open No. 2016-56282). In the manufacturing method of this ashless coal, the extraction time of the solvent soluble component is shortened by heating up the slurry which mixed the solvent and coal rapidly.

In all these conventional manufacturing methods of ashless coal, ashless coal is obtained by isolating a solvent from the solution containing the coal component soluble in a solvent. Therefore, the yield of ashless coal depends on the ratio of the coal component soluble in the solvent, that is, the extraction rate. For this reason, in order to raise the manufacturing efficiency of ashless coal, further improvement of this extraction rate is desired.

Japanese Patent Laid-Open No. 2005-120185 Japanese Patent Laid-Open No. 2016-56282

The present invention has been made based on the circumstances described above, and an object of the present invention is to provide a method for producing ashless coal and an apparatus for producing ashless coal with an increased extraction rate.

MEANS TO SOLVE THE PROBLEM The present inventors discovered that the extraction rate of ashless coal could be raised by adding a radical stabilizer to the slurry before heating and extracting a solvent-soluble component, and completed this invention. This is considered to be because the radical stabilizer can suppress the polymerization by polycondensation of the coal radical which generate|occur|produces by heating of a slurry.

That is, the invention made in order to solve the said subject is a process of heating the mixture of coal, a radical stabilizer, and a solvent, the process of eluting the component soluble in the said solvent from the said coal in the slurry obtained in the said heating process, The said elution A method for producing ashless coal comprising the steps of: separating the slurry after elution in the step into a liquid component containing a solvent-soluble component and a solvent-insoluble component; and evaporating a solvent from the liquid component separated in the separation step. .

In the manufacturing method of the said ashless coal, a radical stabilizer is added to the slurry before heating and extracting a solvent soluble component. Since this radical stabilizer can suppress the polymerization by polycondensation of the coal radical which generate|occur|produces by heating a slurry, the soluble component of the coal eluted by an elution process can be increased. Therefore, the extraction rate of ashless coal can be raised by using the said manufacturing method of ashless coal.

The said heating process should just be equipped with the process of mixing coal, a radical stabilizer, and a solvent, and the process of raising the temperature of the slurry obtained by the said mixing process. Thus, in a heating process, since polymerization of a coal radical can be effectively suppressed by heating up a slurry after mixing a radical stabilizer, the extraction rate of ashless coal can be raised further.

When the heating step includes a step of heating the solvent, a step of conveying the solvent heated in the solvent heating step to the elution step, and a step of supplying coal and a radical stabilizer to the solvent in the solvent conveying step. do. Thus, by supplying coal to the heated solvent in conveyance, while being able to heat up coal rapidly, coal and a solvent can be stirred by the flow of a solvent. Thereby, coal can be melt|dissolved in a solvent in a short time. In addition, by supplying the radical stabilizer together with coal, polymerization of coal radicals can be effectively suppressed, so that the extraction rate of ashless coal can be further increased.

What is necessary is just to adjust the heating temperature of the solvent in the said solvent heating process so that the temperature increase rate of the coal in the said supply process may become 600 degreeC/min or more. Thus, by making the temperature increase rate of the coal in the said supply process more than the said minimum, since polymerization of a coal radical can be suppressed more effectively, the extraction rate of ashless coal can be raised further.

The addition amount of the radical stabilizer to coal on an anhydrous coal basis is preferably 0.045 mmol/g or more and 0.4 mmol/g or less. By carrying out the addition amount of a radical stabilizer into the said range, the extraction rate of ashless coal can be raised effectively, suppressing the raise of the manufacturing cost by addition of a radical stabilizer.

An amine or an ammonium salt may be sufficient as the said radical stabilizer. As such, by using the radical stabilizer as an amine or an ammonium salt, the extraction rate of ashless coal can be further increased.

Monoamine, diamine, or triamine may be sufficient as the said amine. By using the amine as a monoamine, diamine or triamine in this way, the extraction rate of ashless coal can be effectively increased while suppressing an increase in manufacturing cost due to addition of a radical stabilizer.

Another invention made in order to solve the above problem is a heating unit for heating a mixture of coal, a radical stabilizer and a solvent, an elution unit for eluting a component soluble in the solvent from the coal in the slurry obtained by the heating unit; Ashless having a solid-liquid separator for separating the slurry after elution in the elution part into a liquid component containing a solvent-soluble component and a solvent-insoluble component, and an evaporation separation unit for evaporating a solvent from the liquid component separated by the solid-liquid separation unit It is an ammunition manufacturing device.

The said ashless coal manufacturing apparatus heats the slurry to which the radical stabilizer was added in the heating part, and extracts a solvent soluble component. Since this radical stabilizer can suppress the polymerization by polycondensation of the coal radical which generate|occur|produces by heating a slurry, the soluble component of the coal eluted from an elution part can be increased. Therefore, the extraction rate of ashless coal can be raised by using the said ashless coal manufacturing apparatus.

Here, ashless coal (hypercoal, HPC) is a type of reformed coal obtained by reforming coal, and is a reformed coal obtained by removing ash and insoluble components from coal as much as possible using a solvent. However, the ashless coal may contain ash as long as the fluidity and expansibility of the ashless coal are not significantly impaired. Generally, although coal contains 7 mass % or more and 20 mass % or less of ash, in ashless coal, about 2 mass %, you may also contain about 5 % mass of ash in some cases. In addition, "ash content" means the value measured based on JIS-M8812:2004.

As described above, the extraction rate of ashless coal can be increased by using the method and manufacturing apparatus for manufacturing ashless coal of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic which shows the manufacturing apparatus of the ashless coal of 1st Embodiment of this invention.
FIG. 2 is a schematic diagram showing a heating unit different from the heating unit of the apparatus for manufacturing ashless coal of FIG. 1 .
It is a graph which shows the relationship between the addition amount of monoamine in an Example, and an extraction rate increase rate.
It is a graph which shows the relationship between the kind of radical stabilizer in an Example, and an extraction rate increase rate.
5 is a graph showing the relationship between the addition amount of the radical stabilizer to coal and the extraction rate increase rate on an anhydrous coal basis in Examples.

EMBODIMENT OF THE INVENTION Hereinafter, the manufacturing method of the ashless coal which concerns on this invention, and embodiment of the manufacturing apparatus of ashless coal are described.

[First Embodiment]

The apparatus for manufacturing ashless coal shown in FIG. 1 includes a heating unit 1 , an elution unit 2 , a solid-liquid separation unit 3 , a first solvent separation unit 4 , and a second solvent separation unit 5 . ) is mainly provided.

[Heating part]

The heating unit 1 includes a solvent tank 11 , a pump 12 , a preheater 13 , and a feeder 14 for supplying coal and a radical stabilizer. Moreover, the heating part 1 is equipped with the conveyance pipe 15 which conveys the solvent of the solvent tank 11 to the elution part 2 .

<Solvent Tank>

The solvent tank 11 stores the solvent to be mixed with coal.

Although it will not specifically limit if the said solvent melt|dissolves coal, For example, the bicyclic aromatic compound derived from coal is used suitably. Since this bicyclic aromatic compound has a basic structure similar to the structural molecule of coal, it has high affinity with coal, and can obtain a comparatively high extraction rate. Examples of the bicyclic aromatic compound derived from coal include methyl naphthalene oil, naphthalene oil, and the like, which are distillation oils of by-product oil at the time of carbonizing coal to produce coke.

Although the boiling point of the said solvent is not specifically limited, For example, as a lower limit of the boiling point of the said solvent, 180 degreeC is preferable and 230 degreeC is more preferable. On the other hand, as an upper limit of the boiling point of the said solvent, 300 degreeC is preferable and 280 degreeC is more preferable. Since a solvent will volatilize easily that the boiling point of the said solvent is less than the said minimum, there exists a possibility that adjustment and maintenance of the mixing ratio of the coal in a slurry and a solvent may become difficult. Conversely, when the boiling point of the solvent exceeds the upper limit, separation of the solvent-soluble component and the solvent becomes difficult, so that the recovery rate of the solvent may decrease.

<pump>

The pump 12 is disposed in the conveying pipe 15 , and conveys the solvent in the solvent tank 11 to the elution part 2 .

The type of the pump 12 is not particularly limited as long as it can pump the solvent to the elution unit 2 through the conveying pipe 15 , but, for example, a positive displacement pump or a non-displacement pump may be used. More specifically, as a positive displacement pump, a diaphragm pump, a tube fram pump, or the like can be used, and as a non-displacement pump, a vortex pump or the like can be used.

As a lower limit of the pressure (internal pressure of the conveyance pipe 15) at the time of pumping the said solvent to the elution part 2 with the pump 12, 1.1 MPa is preferable and 1.5 MPa is more preferable. On the other hand, as an upper limit of the internal pressure of the said conveyance pipe 15, 5 MPa is preferable and 4 MPa is more preferable. When the internal pressure of the conveying pipe 15 is less than the above lower limit, there is a fear that the coal may be insufficiently dissolved because the power of the solvent to stir the coal at the time of supplying coal to the solvent during conveying, which will be described later, is weakened. Conversely, when the internal pressure of the conveying pipe 15 exceeds the above-mentioned upper limit, there is a fear that the improvement effect of coal dissolution obtained may be insufficient compared to the increase in the cost of manufacturing equipment for ensuring the internal pressure required for the heating unit 1 .

The solvent conveyed by the pump 12 may be conveyed in a laminar flow state, or may be conveyed in a turbulent flow state. Thus, by conveying a solvent in a turbulent state, since the force with which a solvent stirs coal at the time of coal supply to the solvent in conveyance becomes high, while coal becomes easy to mix with a solvent, melt|dissolution of coal is accelerated|stimulated. Here, the "laminar flow state" refers to a state in which the Reynolds number Re is less than 2100, and the "turbulent flow state" refers to a state in which the Reynolds number Re is 2100 or more, and more preferably, the Reynolds number Re is 4000 or more.

As a lower limit of the flow rate of the said solvent conveyed by the pump 12, 0.5 m/sec is preferable and 1 m/sec is more preferable. On the other hand, as an upper limit of the flow rate of the said solvent, 10 m/sec is preferable and 5 m/sec is more preferable. When the flow rate of the solvent is less than the lower limit, the power of the solvent to stir the coal at the time of supply of coal to the solvent during conveyance is weakened, so that there is a possibility that the coal may be insufficiently dissolved. On the other hand, when the flow rate of the said solvent exceeds the said upper limit, there exists a possibility that the improvement effect of the coal melt|dissolution obtained compared with the cost increase for making the pump 12 powerful may become inadequate.

<Preheater>

The preheater 13 is not particularly limited as long as it can heat the solvent passing through the preheater 13 , and examples thereof include a resistance heating type heater and an induction heating coil. Moreover, you may heat using a heat medium. For example, the solvent passing through the preheater 13 can be heated by arranging a heating tube around the flow path of the solvent passing through the preheater 13 and supplying a heating medium such as steam or oil to the heating tube.

As a lower limit of the solvent temperature after heating by the preheater 13, 300 degreeC is preferable and 350 degreeC is more preferable. On the other hand, as an upper limit of the temperature of the said solvent, if it is a temperature which can elute, Although it will not specifically limit, 480 degreeC is preferable and 450 degreeC is more preferable. When the temperature of the solvent is less than the lower limit, the bond between molecules constituting the coal in the elution part 2 cannot be sufficiently weakened, and there is a possibility that the elution rate may decrease. Conversely, when the temperature of the solvent exceeds the upper limit, since the amount of heat for maintaining the temperature of the solvent becomes unnecessarily large, there is a fear that the manufacturing cost increases.

The lower limit of the heating rate by the preheater 13 is preferably 10°C/min, more preferably 20°C/min. On the other hand, as an upper limit of the said heating rate, 100 degreeC/min is preferable and 50 degreeC/min is more preferable. When the heating rate is less than the lower limit, it takes time to heat the solvent to a predetermined temperature, so there is a fear that the production efficiency of the ashless coal may be lowered. Conversely, when the heating rate exceeds the upper limit, there is a fear that the cost of heating energy or manufacturing equipment is unnecessarily increased.

Although it does not specifically limit as heating time by the preheater 13, From the relationship between the temperature and heating rate mentioned above, it can be set as 10 minutes or more and 30 minutes or less, for example.

<Feeder>

The feeder 14 supplies coal and a radical stabilizer to the conveyance pipe 15 . As the feeder 14, well-known hoppers, such as a normal pressure hopper used in a normal pressure state, and a pressurization hopper used in a normal pressure state and pressurized state, can be used. The coal and the radical stabilizer are mixed and put into the hopper.

(Coal)

As the coal to be supplied from the feeder 14 , coal of various qualities can be used. As said coal, bituminous coal with a high extraction rate of ashless coal, and cheaper thermal coal (subbituminous coal or lignite) are used suitably, for example. In addition, when coal is classified by particle size, finely pulverized coal is suitably used. Here, "finely pulverized coal" means coal in which the mass ratio of coal with a particle size of less than 1 mm with respect to the mass of the whole coal is 80% or more, for example. Moreover, lump coal can also be used as the coal supplied from the feeder 14. As shown in FIG. Here, "bullet coal" means, for example, coal in which the mass ratio of the coal with a particle size of 5 mm or more with respect to the mass of the whole coal is 50 % or more. Since lump coal has a larger particle size than finely pulverized coal, separation in the solid-liquid separation unit 3 described later can be made more efficient. Here, "particle size (particle size)" means the value measured based on the sieving test general rule of JIS-Z8815 (1994). In addition, the metal mesh sieve prescribed|regulated to JIS-Z8801-1 (2006) can be used for classification by the particle size of coal, for example.

Moreover, from a viewpoint of shortening of an elution time, it is preferable to use what contains a lot of thermal coal as coal supplied from the feeder 14. As shown in FIG. In this case, as a minimum of the ratio of the thermal coal in the whole coal to be supplied, 80 mass % is preferable and 90 mass % is more preferable. When the ratio of the thermal coal contained in the coal to be supplied is less than the said minimum, there exists a possibility that the time which elutes a solvent soluble component may become long.

As a lower limit of the carbon content rate of the said hot carbon, 70 mass % is preferable. On the other hand, as an upper limit of the carbon content rate of the said hot coal, 85 mass % is preferable and 82 mass % is more preferable. There exists a possibility that the elution rate of a solvent-soluble component may fall that the carbon content rate of the said heat carbon is less than the said lower limit. Conversely, when the carbon content of the thermal coal exceeds the upper limit, the cost of the coal to be supplied may increase.

(radical stabilizer)

The radical stabilizer is mixed with the coal and fed into the feeder 14 .

Examples of the radical stabilizer include amine-based stabilizers and phenol-based stabilizers. Among them, amine-based stabilizers such as amines and ammonium salts are preferable, and amines are particularly preferable. Moreover, as said amine, monoamines, such as octadecylamine, diamines, such as N-alkyl-1, 3- diamino propane, or triamines, such as tallow dipropylenetriamine, are preferable, and monoamine is more preferable.

As a lower limit of the addition amount of the said radical stabilizer with respect to coal on an anhydrous coal basis, 0.045 mmol/g is preferable and 0.15 mmol/g is more preferable. On the other hand, as an upper limit of the addition amount of the said radical stabilizer, 0.4 mmol/g is preferable and 0.22 mmol/g is more preferable. If the addition amount of the radical stabilizer is less than the lower limit, there is a possibility that the effect of improving the extraction rate of the ashless coal may be insufficient. Conversely, when the addition amount of the radical stabilizer exceeds the upper limit, there is a fear that the cost of the radical stabilizer becomes excessively high compared to the effect of improving the extraction rate of ashless coal.

The mixture of the coal and the radical stabilizer may be preheated. By preheating the mixture, it is possible to prevent the temperature of the slurry from lowering when it is supplied to the conveying pipe 15 and mixed with a solvent. Although it does not specifically limit as a preheating temperature of the said mixture, For example, it can be 200 degreeC or more and 300 degrees C or less.

Moreover, as the said mixture supplied from the feeder 14 to the conveyance pipe 15, you may use the mixture which mixed and slurried the solvent. By supplying the slurried mixture from the feeder 14 to the conveyance pipe 15, coal and a radical stabilizer become easy to mix with a solvent in the conveyance pipe 15, and coal can be melt|dissolved more quickly.

The lower limit of the coal concentration on the anhydrous coal basis in the slurry is preferably 20 mass %, more preferably 30 mass %. On the other hand, as an upper limit of the said coal concentration, 70 mass % is preferable and 60 mass % is more preferable. When the coal concentration is less than the lower limit, the elution amount of the solvent-soluble component eluted from the elution part 2 to be described later becomes smaller than the slurry treatment amount, so there is a fear that the production efficiency of the ashless coal may decrease. Conversely, when the said coal concentration exceeds the said upper limit, there exists a possibility that the mixing facilitation effect of the coal and solvent by slurrying may become inadequate.

<Return tube>

The conveyance pipe 15 conveys the solvent of the solvent tank 11 to the elution part 2 . In addition, the mixture of coal and radical stabilizer supplied from the feeder 14 to the conveying pipe 15 is mixed with the heated solvent flowing through the conveying pipe 15 in this conveying pipe 15, and the temperature is raised rapidly. Here, "rapid temperature increase" means heating at a heating rate of, for example, about 10°C/sec or more and 500°C/sec or less. As a result, the temperature of the slurry, which is a mixture of the solvent, coal, and the radical stabilizer, becomes relatively uniform for several seconds to several tens of seconds after the coal and the radical stabilizer are added. In addition, the temperature of the said slurry is lower than the temperature of the solvent after heating by the sensible heat of coal, for example, about 350 degreeC or more and 420 degrees C or less.

As a minimum of the coal concentration in the said slurry on an anhydrous basis, 5 mass % is preferable and 10 mass % is more preferable. On the other hand, as an upper limit of the said coal concentration, 40 mass % is preferable and 30 mass % is more preferable. When the coal concentration is less than the lower limit, the elution amount of the solvent-soluble component eluted from the elution part 2 to be described later becomes smaller than the slurry treatment amount, so there is a fear that the production efficiency of the ashless coal may decrease. Conversely, when the coal concentration exceeds the upper limit, since the solvent-soluble component is saturated in the solvent, there is a fear that the dissolution rate of the solvent-soluble component is lowered.

[Elution part]

The elution part 2 elutes the coal component soluble in a solvent from the said coal in the slurry obtained by the said heating part 1 . The elution part 2 has an extraction tank 21 .

Slurry is supplied to the extraction tank 21 from the conveyance pipe 15 . In the said extraction tank 21, the coal component soluble in a solvent is eluted from coal, maintaining the temperature of this slurry. Moreover, the said extraction tank 21 has the stirrer 21a. The said elution can be accelerated|stimulated by stirring a slurry with this stirrer 21a.

As a lower limit of the internal pressure of the said extraction tank 21, 1.1 MPa is preferable and 1.5 MPa is more preferable. On the other hand, as an upper limit of the internal pressure of the said extraction tank 21, 5 MPa is preferable and 4 MPa is more preferable. When the internal pressure of the extraction tank 21 is less than the said lower limit, it reduces by evaporation of a solvent, and there exists a possibility that dissolution of coal may become inadequate. Conversely, when the internal pressure of the extraction tank 21 exceeds the upper limit, there is a fear that the effect of improving the coal dissolution obtained may be insufficient compared to an increase in cost for maintaining the pressure.

In addition, although it does not specifically limit as elution time in the elution part 2, From a viewpoint of the extraction amount of a solvent soluble component, and extraction efficiency, it can be set as 10 minutes or more and 70 minutes or less.

The slurry from which the soluble coal component is eluted from the elution part 2 is sent to the solid-liquid separation part 3 through a supply pipe.

[Solid-liquid separation unit]

The solid-liquid separation unit 3 separates the solution in which the coal component obtained in the elution unit 2 is dissolved in a solvent and the solid content concentrate containing the solvent-insoluble component from the slurry. In addition, a solvent-insoluble component is mainly comprised from the ash which is insoluble in the solvent for extraction, and insoluble coal, and says the extraction residue which also contains the solvent for extraction.

The said separation in the solid-liquid separation part 3 can be performed by the gravity sedimentation method, for example. Here, the gravity sedimentation method is a separation method in which solid content is sedimented using gravity in a sedimentation tank and solid-liquid separation is performed. When separation is performed by the gravity sedimentation method, the solution containing the solvent-soluble component accumulates in the upper portion of the solid-liquid separation unit 3 . This solution is filtered using a filter unit if necessary, and then discharged to the first solvent separation unit 4 . On the other hand, the solid content concentrate containing the solvent-insoluble component accumulates in the lower portion of the solid-liquid separation unit 3 , and is discharged to the second solvent separation unit 5 .

In addition, when separation is performed by gravity sedimentation, the liquid content containing the solvent-soluble component and the solid content concentrated liquid containing the solvent-insoluble component can be discharged from the settling tank while continuously supplying the slurry into the solid-liquid separation unit 3 . . Thereby, continuous solid-liquid separation processing becomes possible.

The time for holding the slurry in the solid-liquid separation unit 3 is not particularly limited, and can be, for example, 30 minutes or more and 120 minutes or less, and sedimentation separation in the solid-liquid separation unit 3 is performed within this time period. Moreover, since sedimentation separation becomes efficient when using lump coal as coal, the time for holding a slurry in the solid-liquid separation part 3 can be shortened.

The inside of the solid-liquid separation unit 3 is preferably heated and pressurized. As a lower limit of the heating temperature in the solid-liquid separation part 3, 300 degreeC is preferable and 350 degreeC is more preferable. On the other hand, as an upper limit of the heating temperature in the solid-liquid separation part 3, 420 degreeC is preferable and 400 degreeC is more preferable. If the said heating temperature is less than the said minimum, a solvent-soluble component may re-precipitate, and there exists a possibility that separation efficiency may fall. Conversely, when the heating temperature exceeds the upper limit, there is a fear that the operating cost for heating becomes high.

Moreover, as a pressure lower limit in the solid-liquid separation part 3, 1 MPa is preferable and 1.4 MPa is more preferable. On the other hand, as an upper limit of the said pressure, 3 MPa is preferable and 2 MPa is more preferable. When the pressure is less than the lower limit, there is a fear that the solvent-soluble component is re-precipitated and the separation efficiency is lowered. Conversely, when the pressure exceeds the upper limit, there is a risk that the operating cost for pressurization becomes high.

In addition, as a method of isolate|separating the said solution and a solid content concentrate, it is not limited to the gravity sedimentation method, For example, a filtration method or a centrifugal separation method may be used. When a filtration method or a centrifugal separation method is used as the solid-liquid separation method, a filter, a centrifugal separator, or the like is used as the solid-liquid separation unit 3 .

[First Solvent Separation Unit]

The first solvent separation unit 4 evaporates the solvent from the solution separated by the solid-liquid separation unit 3 . Ashless coal HPC is obtained by evaporative separation of this solvent. This first solvent separation unit 4 may be referred to as an evaporation separation unit.

The ashless coal HPC obtained in this way shows a higher calorific value than the raw material coal of coke, for example. In addition, ashless coal has significantly improved softening meltability, which is a particularly important quality as a raw material for coke for ironmaking, and exhibits a fluidity much superior to that of raw material coal, for example. Therefore, ashless coal can also be used as coal mix|blended with a coke raw material.

As a method of evaporatively separating the solvent, a general distillation method using an evaporative separator or a separation method including an evaporation method (spray drying method, etc.) can be used.

In addition, the solvent evaporated by the 1st solvent separation part 4 is liquefied, for example by a heat exchanger, is supplied to the heating part 1, What is necessary is just to use it as a solvent mixed with coal and a radical stabilizer. By circulating and using the solvent in this way, the manufacturing cost of ashless coal can be reduced.

[Second solvent separation unit]

The 2nd solvent separation part 5 evaporates a solvent from the said solid content concentrate separated by the solid-liquid separation part 3, and obtains by-product coal RC.

Although by-product coal RC does not show softening meltability, an oxygen-containing functional group is detached. Therefore, by-product coal RC does not impair the softening meltability of the other coal contained in this coal blend, when it uses as a coal blended coal. Therefore, this by-product coal RC can be used as a part of coal blending of a coke raw material, for example. In addition, you may use by-product coal RC as a fuel similarly to general coal.

As a method of isolating the solvent from the solid content concentrate, a general distillation method using an evaporative separator or an evaporation method (spray drying method, etc.) can be used similarly to the separation method of the first solvent separation unit 4 .

In addition, the solvent evaporated by the 2nd solvent separation part 5 is liquefied, for example by a heat exchanger, is supplied to the heating part 1, What is necessary is just to use it as a solvent mixed with coal and a radical stabilizer. By circulating and using the solvent in this way, the manufacturing cost of ashless coal can be reduced.

[Method for producing ashless coal]

The manufacturing method of the said ashless coal is equipped with a heating process, an elution process, a separation process, a 1st evaporation process, and a 2nd evaporation process. The manufacturing method of the said ashless coal can be performed using the manufacturing apparatus of the ashless coal of FIG.

<Heating process>

In the heating process, a mixture of coal, a radical stabilizer and a solvent is heated. A heating process is equipped with a solvent heating process, a solvent conveyance process, and the supply process of supplying coal and a radical stabilizer.

In the said solvent heating process, a solvent is heated. Specifically, the solvent stored in the solvent tank 11 is flowed by the pump 12 to the conveying pipe 15 , and the solvent flowing in the conveying pipe 15 is heated while passing through the preheater 13 .

In the said solvent conveyance process, the said solvent heated in the said solvent heating process is conveyed to the said elution process. Specifically, the solvent is supplied to the elution part 2 by the conveyance pipe 15 .

In the said supply process, coal and a radical stabilizer are supplied to the said solvent in the said solvent conveyance process. Specifically, coal and a radical stabilizer are supplied from a feeder 14 to a conveying pipe 15 through which the solvent after heating flows, and coal and a radical stabilizer are mixed with a solvent to form a slurry. The coal and radical stabilizer supplied to the conveying pipe 15 are rapidly heated by the solvent, and since the solvent flowing through the conveying pipe 15 stirs the coal, the coal is easily dissolved, and a slurry in which the solvent and coal are well mixed is formed. is obtained

As a minimum of the temperature increase rate of the coal in the said supply process, 600 degreeC/min is preferable and 700 degreeC/min is more preferable. When the temperature increase rate is less than the lower limit, the effect of improving the extraction rate of ashes by the radical stabilizer may be insufficient. In addition, although it does not specifically limit as an upper limit of the said temperature increase rate, It can be set as 30000 degreeC/min. When the temperature increase rate exceeds the upper limit, there is a fear that the cost for temperature increase is unnecessarily increased. In addition, the said temperature increase rate can be adjusted according to the heating temperature of the solvent in the said solvent heating process.

<Elution process>

At an elution process, the coal component soluble in a solvent is eluted from the said coal in the slurry obtained by the said heating process. Specifically, the slurry prepared in the heating step is supplied to the extraction tank 21, and the solvent-soluble component is extracted while maintaining it at a predetermined temperature while stirring with the stirrer 21a.

<Separation process>

In a separation process, the said slurry after elution in the said elution process is isolate|separated into the liquid content containing a solvent-soluble component, and the solid content concentrate containing the solvent-insoluble component. Specifically, the slurry discharged from the extraction tank 21 is supplied to the solid-liquid separation unit 3, and the slurry supplied into the solid-liquid separation unit 3 is converted into the liquid and solid contents concentrate by, for example, gravity sedimentation. separate

<First evaporation step>

In a 1st evaporation process, a solvent is evaporated from the said solution isolate|separated in the said separation process. Specifically, the solution separated in the solid-liquid separation unit 3 is supplied to the first solvent separation unit 4 , and the solvent is evaporated in the first solvent separation unit 4 . Thereby, the solution is separated into a solvent and ashless coal.

<Second evaporation process>

In a 2nd evaporation process, a solvent is evaporated from the said solid content concentrate separated in the said separation process. Specifically, the solid content concentrate separated in the solid-liquid separation unit 3 is supplied to the second solvent separation unit 5 , and the solvent is evaporated in the second solvent separation unit 5 to separate the solvent and by-product coal.

[advantage]

In the manufacturing apparatus of the said ashless coal, and the manufacturing method of the said ashless coal, a radical stabilizer is added to the slurry before heating and extracting a solvent soluble component. Since this radical stabilizer can suppress the polymerization by polycondensation of the coal radical which generate|occur|produces by heating a slurry, the soluble component of the eluted coal can be increased. Therefore, the extraction rate of ashless coal can be raised by using the said ashless coal manufacturing apparatus and the said ashless coal manufacturing method.

Moreover, in the said ashless coal manufacturing apparatus and the said ashless coal manufacturing method, by supplying coal to the heated solvent during conveyance, the coal can be heated up rapidly, and the coal and the solvent are stirred by the flow of the solvent. can Thereby, coal can be melt|dissolved in a solvent in a short time. In addition, by supplying the radical stabilizer together with coal, polymerization of coal radicals can be effectively suppressed, so that the extraction rate of ashless coal can be further increased.

[Second Embodiment]

The heating unit 10 of FIG. 2 is used instead of the heating unit 1 of the apparatus for manufacturing an ashes of FIG. 1 . The heating unit 10 of FIG. 2 includes a solvent tank 11 , a feeder 14 , a mixing unit 16 , a pump 17 , and a temperature increasing unit 18 . In addition, since the solvent tank 11 and the feeder 14 are the same as that in the manufacturing apparatus of an ashes of FIG. 1, it attaches the same correspondence and abbreviate|omits description.

<Mixed part>

The mixing unit 16 mixes the solvent supplied from the solvent tank 11 with the coal and radical stabilizer supplied from the supply unit 14 .

As the mixing unit 16 , a preparation tank 19 can be used. The coal, the radical stabilizer and the solvent are supplied to the preparation tank 19 through a supply pipe. In the said preparation tank 19, this supplied coal, a radical stabilizer, and a solvent are mixed, and a slurry is prepared. Moreover, the said preparation tank 19 has the stirrer 19a, The mixed state of the slurry is maintained by holding the mixed slurry while stirring with the stirrer 19a.

Moreover, the slurry prepared in the preparation tank 19 of the mixing part 16 is sent to the temperature raising part 18 through a supply pipe.

<pump>

The pump 17 is disposed in a supply pipe for supplying the slurry from the mixing unit 16 to the temperature increasing unit 18 , and pressurizes the slurry stored in the preparation tank 19 to the temperature increasing unit 18 .

The type of the pump 17 is not particularly limited as long as it can pump the slurry to the temperature increasing unit 18 through a supply pipe, but, for example, a positive displacement pump or a non-displacement pump may be used. As said positive displacement pump, a diaphragm pump, a tube fram pump, etc. are mentioned, As said non-displacement type pump, a vortex pump etc. are mentioned.

<Temperature Raising Unit>

The temperature increasing unit 18 raises the temperature of the slurry obtained in the mixing unit 16 .

Although it will not specifically limit as the temperature rising part 18 if it can raise the temperature of the slurry passing through, For example, a resistance heating type heater and an induction heating coil are mentioned. Moreover, the temperature raising part 18 may be comprised so that the temperature may be raised using a heating medium, for example, it has a heating tube arrange|positioned around the flow path of the slurry passing through inside, It has steam, oil, etc. in this heating tube. The temperature of the slurry may be increased by supplying the heating medium.

As a lower limit of the temperature of the slurry after the temperature increase by the temperature raising part 18, 300 degreeC is preferable and 360 degreeC is more preferable. On the other hand, as an upper limit of the temperature of the said slurry, 420 degreeC is preferable and 400 degreeC is more preferable. If the temperature of the slurry is less than the lower limit, the bond between molecules constituting the coal cannot be sufficiently weakened, and there is a possibility that the dissolution rate may decrease. Conversely, when the temperature of the slurry exceeds the upper limit, since the amount of heat for maintaining the temperature of the slurry becomes unnecessarily large, there is a fear that the manufacturing cost of the porous carbon particles increases.

[Method for producing ashless coal]

The manufacturing method of the said ashless coal is equipped with a heating process, an elution process, a separation process, a 1st evaporation process, and a 2nd evaporation process. The manufacturing method of the said ashless coal can be performed using the manufacturing apparatus of the ashless coal which has the heating part 10 of FIG. In addition, since an elution process, a separation process, a 1st evaporation process, and a 2nd evaporation process can be performed similarly to the ashless coal manufacturing method of 1st Embodiment, only a heating process is demonstrated here.

<Heating process>

In the heating process, a mixture of coal, a radical stabilizer and a solvent is heated. The said heating process is equipped with a mixing process and a temperature raising process.

In a mixing process, coal, a radical stabilizer, and a solvent are mixed. The coal and radical stabilizer supplied from the feeder 14, and the solvent supplied from the solvent tank 11 are specifically, mixed by the preparation tank 19 of the mixing part 16, and let it be a slurry.

In a temperature raising process, the slurry obtained by the said mixing process is heated up. Specifically, the slurry is heated by supplying the slurry to the temperature increasing unit 18 by the pump 17 .

[advantage]

In the apparatus for producing the ashless coal and the method for producing the ashless coal, by heating the slurry after mixing the radical stabilizer, polymerization of coal radicals can be effectively suppressed, so that the extraction rate of the ashless coal can be further increased.

[Other embodiments]

In addition, the manufacturing apparatus of ashless coal and the manufacturing method of ashless coal of this invention are not limited to the said embodiment.

Although the said embodiment demonstrated the structure which supplies the mixture which mixed coal and the radical stabilizer previously from a feeder, you may supply separately coal and a radical stabilizer.

Moreover, although the said embodiment demonstrated the case where a 2nd evaporation process is provided as a manufacturing method of ashless coal, for example, when by-product coal is not used, this 2nd evaporation process can be abbreviate|omitted. When not performing a 2nd evaporation process, the manufacturing apparatus of ashless coal does not need to be equipped with a 2nd solvent separation part.

In the first embodiment, the case where the preheater is disposed on the downstream side of the pump as the heating unit has been described. However, the arrangement order of the pump and the preheater may be reversed.

In the second embodiment, the configuration in which the mixing section of the apparatus for producing ashless coal has an auxiliary tank is described. However, the structure is not limited to this configuration, and if the solvent, coal, and radical stabilizer are mixed, the auxiliary tank may be omitted. For example, when the said mixing is completed by a line mixer, it is good also as a structure which abbreviate|omits a preparation tank and provides a line mixer between a supply pipe and a temperature rising part.

Example

Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.

As coal, 40 g of bituminous coal was prepared. In addition, the said coal was grind|pulverized and used so that the ratio of the coal with a particle diameter of less than 1 mm with respect to all coal might be set to 90 mass % or more. In addition, 240 g of 1-methylnaphthalene was prepared as a solvent for extraction of ashless coal. The coal and the solvent were mixed to prepare a slurry.

As a radical stabilizer, 2 g of octadecylamine, which is a monoamine, was prepared and added to the slurry and mixed.

The slurry was put into an autoclave having a capacity of 500 cc having a stainless filter, and the temperature was raised to 380°C under a pressure condition of 2 MPa. And it stirred for 40 minutes, maintaining temperature at 380 degreeC, and the coal component soluble in a solvent was eluted from coal.

Filtration was performed with the said extraction temperature, the mass of the filter residue (solvent-insoluble component) was measured, and the ratio of the coal component soluble in a solvent, ie, an extraction rate, was computed.

The same process was performed with the addition amount of monoamine being 0 g, 0.5 g, 1 g, and 4 g. In addition, "the addition amount of a monoamine shall be 0 g" means that a monoamine is not added.

The increase rate (mass %) of the extraction rate in another addition amount was computed on the basis of the extraction rate when the addition amount of monoamine was 0 g. The results are shown in FIG. 3 . In addition, "increase rate" is an amount calculated as (Y-X)/X x 100 when X is the extraction rate when the addition amount is 0 g, and Y is the extraction rate under the conditions for calculating the increase rate. In addition, in FIG. 3, the horizontal axis is converted into the addition amount (mmol/g) of the said radical stabilizer with respect to coal on an anhydrous coal basis.

From the result of FIG. 3, it can be seen that the effect is seen when the amount of addition is 0.045 mmol/g or more (the increase in extraction rate becomes 3% or more), and the extraction rate increases in proportion to the amount of monoamine added up to about 0.4 mmol/g. have.

In addition, while the addition amount of the radical stabilizer was fixed at 2 g, the types of the radical stabilizer were selected as primary monoamine octadecylamine (amine A), secondary monoamine dioctadecylamine (amine B), and quaternary ammonium salt. of dialkyldimethylammonium chloride (amine C), N-alkyl-1, 3-diaminopropane (amine D) of primary diamine, and tallow dipropylenetriamine (amine E) of primary triamine, the same was processed, and the increase rate (mass %) of the extraction rate was calculated. The results are shown in FIG. 4 . In addition, it shows that the above-mentioned result in FIG. 5 is graphed based on the addition amount (mol amount) of the radical stabilizer to coal on an anhydrous coal basis.

From the results of Figures 4 and 5, it can be seen that the extraction rate is increased in any radical stabilizer. Among them, it can be seen that when monoamine is used as a radical stabilizer, the increase rate of the extraction rate is high. In addition, it can be seen that the extraction rate can be increased by increasing the addition amount of the radical stabilizer to the coal on the basis of anhydrous coal. From the above, it is thought that an extraction rate can be raised by adding a radical stabilizer.

As described above, by using the ashless coal manufacturing method and manufacturing apparatus of the present invention, the extraction rate of the ashless coal can be increased.

1, 10: heating part
11: solvent tank
12, 17: pump
13: Preheater
14: feeder
15: return pipe
16: mixing part
18: temperature rising unit
19: Jojo
19a: agitator
2: dissolution part
21: brew tank
21a: agitator
3: solid-liquid separation unit
4: first solvent separation unit
5: second solvent separation unit

Claims (8)

A process of obtaining a slurry by mixing a part of coal and a radical stabilizer with a solvent in the supply unit;
a step of heating the slurry to 200°C or higher and 300°C or lower;
The process of raising the temperature of the remainder of the said solvent stored by the solvent tank to 300 degreeC or more and 450 degrees C or less;
a step of conveying the solvent, which has been heated in the conveying pipe, in a turbulent state to the elution section;
supplying the heated slurry to the solvent conveyed in the turbulent flow state to make a mixture, and further heating the mixture;
a step of eluting a component of the coal soluble in the solvent from the mixture in the elution unit;
A step of separating a solution in which the coal component is dissolved from the mixture in which the coal component is eluted in a solid-liquid separation unit and a solid content concentrate containing a solvent-insoluble component;
A process of evaporating the solvent from the solution in the solvent separation unit
to provide
In the process of obtaining the slurry,
The mass ratio of the coal having a particle size of less than 1 mm to the mass of the entire coal is 80% or more,
The addition amount of the radical stabilizer to the coal on an anhydrous coal basis is 0.045 mmol/g or more and 0.4 mmol/g or less,
The radical stabilizer is an amine or an ammonium salt,
Wherein the amine is a monoamine, diamine or triamine. According to claim 1,
In the mixture temperature increasing step, the heating temperature of the solvent in the solvent residual temperature increasing step is adjusted so that the temperature increase rate of the slurry is 600° C./min or more. a heating unit for heating a mixture of coal, a radical stabilizer and a solvent;
an elution unit for eluting a component of the coal soluble in the solvent from the mixture;
a solid-liquid separation unit separating a solution in which the coal component is dissolved from the mixture in which the coal component is eluted and a solid concentration and insecticide solution containing a solvent-insoluble component;
Evaporation separation unit for evaporating the solvent from the solution separated in the solid-liquid separation unit
to provide
the heating unit,
a supply unit for mixing the coal and radical stabilizer with a part of the solvent to form a slurry;
a solvent tank for storing the remainder of the solvent;
A preheater for raising the temperature of the solvent to 300°C or higher and 450°C or lower;
A conveying pipe for conveying the heated solvent to the elution section in a turbulent flow state and further increasing the temperature of the mixture with the slurry supplied to the solvent
have,
In the supply unit,
The mass ratio of the coal having a particle size of less than 1 mm to the mass of the entire coal is 80% or more,
The addition amount of the radical stabilizer to the coal on an anhydrous coal basis is 0.045 mmol/g or more and 0.4 mmol/g or less,
The radical stabilizer is an amine or an ammonium salt,
The amine is a monoamine, diamine or triamine, an apparatus for producing ashless coal. delete delete delete delete delete

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