KR102014245B1 - Coal-fired power generation system having coal moisture removal apparatus - Google Patents

Abstract

SUMMARY OF THE INVENTION An object of the present invention is to provide a coal-fired power generation system that can use coal as a fuel by efficiently eliminating moisture contained in coal and increasing calorific value. Coal-fired power generation system according to the present invention for achieving the above object is a coal crushing unit for grinding coal; A coal drying unit accommodating the pulverized coal and removing moisture of the coal; A coal boiler for burning the pulverized coal dried in the coal drying unit; An electricity generation unit installed inside the coal boiler and having a steam drum including steam for obtaining thermal energy generated by combustion of the pulverized coal, and a steam turbine connected to the steam drum; A condenser unit for recovering thermal energy from the steam passing through the steam turbine to condense the steam; A hot air movement passage having an intake unit through which external air is sucked in, a heat energy acquisition unit disposed inside the condenser unit, and an exhaust unit connected to the coal drying unit, and blowing the air sucked from the intake unit to the discharge unit side. It includes a hot air supply having a blower.

Description

Coal-fired power generation system with coal drying unit {COAL-FIRED POWER GENERATION SYSTEM HAVING COAL MOISTURE REMOVAL APPARATUS}

The present invention relates to a coal-fired power generation system having a coal drying unit.

Coal is divided into high grade coal and low grade coal according to the degree of carbonization. In general, high grade coal has a low water content, and low grade coal has a relatively high water content. Due to this difference in water content, low grade coal has a low possibility of complete combustion and a low calorific value is not suitable for use as it is as a fuel. In addition, low-grade coal is less likely to burn completely, so the amount of unburned coal is relatively higher than that of high-grade coal.

Due to the problem of low grade coal, most domestic coal-fired power plants use high grade coal as fuel. However, as the price of high-grade coal increases due to the increase in demand for power generation, it is becoming difficult to supply it stably. Therefore, the need to use it as a fuel to solve the problem of high water content of low-grade coal, which is relatively rich in reserves.

On the other hand, in coal-fired power plant boilers, coal ash (Ash) is generated after burning coal, and when the content of coal briquettes (LOI, loss of ignition) is less than 6%, it is recycled as raw materials such as aggregate, but it is more than 6%. In this case, there is a problem that cannot be recycled.

An object of the present invention is to provide a coal-fired power generation system that can increase the combustion rate of coal to improve the calorific value and minimize the coal briquettes.

Another object of the present invention is to provide a coal-fired power generation system that can efficiently process the coal briquettes.

Coal-fired power generation system according to the present invention for achieving the above object is a coal crushing unit for grinding coal; A coal drying unit accommodating the pulverized coal and removing moisture of the coal; A coal boiler for burning the pulverized coal dried in the coal drying unit; An electricity generation unit installed inside the coal boiler and having a steam drum including steam for obtaining thermal energy generated by combustion of the pulverized coal, and a steam turbine connected to the steam drum; A condenser unit for recovering thermal energy from the steam passing through the steam turbine to condense the steam; A hot air movement passage having an intake unit through which external air is sucked in, a heat energy acquisition unit disposed inside the condenser unit, and an exhaust unit connected to the coal drying unit, and blowing the air sucked from the intake unit to the discharge unit side. It includes a hot air supply having a blower.

Here, the coal drying unit has an input unit into which the pulverized coal is input and extends in the horizontal direction, and the pulverized coal is blocked but the air is connected to the inner cylinder part made of a membrane material passing through the discharge unit. An outer cylinder portion having a dry air inlet portion and a dry air outlet portion through which the air introduced from the dry air inlet portion is discharged, the outer cylinder portion rotatably supporting the inner cylinder portion around the horizontal axis outside the inner cylinder portion; It is preferred that the outer cylinder is provided with a drive roller unit for providing a driving force so that the inner cylinder is rotated about the horizontal axis.

And it is preferable that the inner cylinder portion has a coating section provided with a coating spraying unit for spraying a hydrophobic coating agent to the pulverized coal in at least some section.

The inner cylinder may further include a predrying section for predrying the pulverized coal at the front end of the coating section, and a final drying section for finally drying the coated pulverized coal at the rear end of the coating section. It is preferable to have.

The outer cylinder includes a coal receiving unit for receiving the pulverized coal, a dry coal supply passage connecting the coal receiving unit and the boiler, and an open / close valve for opening and closing the dry coal supply passage at the discharge end of the inner cylinder. It is preferable to include.

Coal-fired power generation system according to the present invention can efficiently remove the moisture contained in the coal through the coal drying unit, and thus can be used as the fuel of the boiler with a high burnability and high calorific value. The coal-fired power generation system can use low-cost coal, which is relatively inexpensive, as a fuel, thereby reducing the operation cost of the power plant, and lowering the ash content of ash produced during the combustion of coal.

1 is a schematic view showing a coal-fired power generation system having a coal drying unit according to the present invention,
2 is a cross-sectional view schematically showing a coal drying unit according to the present invention,
3 is a flow chart showing a method for pelletizing the coal briquette powder according to the present invention,
4 is an explanatory view showing a coal briquette separation unit for separating the coal briquette powder from the ash according to the present invention;
5 is a flowchart illustrating a method for separating coal briquettes using the coal briquette separation unit 230 according to the present invention.

1 is a schematic view showing a coal-fired power generation system having a coal drying unit 120 according to the present invention. As shown in FIG. 1, the coal-fired power generation system includes a coal crushing unit 110 for crushing coal. The coal crushing unit 110 finely crushes coal, that is, raw coal, to be used as a fuel of the boiler 130. The pulverized coal is transferred to the coal drying unit 120 through the pulverized coal transfer pipe 111.

2 is a cross-sectional view schematically showing a coal drying unit 120 according to the present invention. Referring to Figure 2 with reference to Figure 1, the coal drying unit 120 is supported by the inner cylinder portion 1230 extending along the horizontal direction and the inner cylinder portion 1230 rotatably around the horizontal axis in the outside thereof. It includes an outer cylinder portion 1250.

The inner cylinder part 1230 has an input part 1231 into which pulverized coal is input. The input part 1231 is connected to a coal supply pipe 111 to which pulverized coal is supplied. At this time, the bearing 1211 is installed between the supply pipe 111 and the outer cylinder 1250 so that the inner cylinder 1230 is rotatable. In addition, the pulverized coal supplied from the supply pipe 1210 is preferably quantitatively supplied without being dispersed by a transport screw. The inner cylinder part 1230 is made of a membrane material that blocks the pulverized coal but allows air to pass through.

The inner cylinder part 1230 has a coating section in which a coating agent spray unit 1235 for spraying a hydrophobic coating agent on the pulverized coal is installed. Wherein the hydrophobic coating agent comprises a biomass-derived carbon component. The biomass-derived carbon component is preferably a sugar obtained from sugarcane stock solution or molasses or obtained by enzymatic decomposition of a sugar or starch system converted from lignocellulosic of wood. For preparing the hydrophobic coating agent may refer to Republic of Korea Patent Publication No. 10-1195416.

The inner cylinder part 1230 has a predrying section and a final drying section, respectively, before and after the coating section. That is, the predrying section, the coating section and the final drying section are sequentially disposed along the moving direction of the pulverized coal supplied through the input part 1231. In FIG. 2, the predrying section, the coating section, and the final drying section are not explicitly indicated, but the stirring blades 1233 installed in the predrying section and the coating spraying part 1235 installed in the coating section and the stirring provided in the final drying section. Each section may be distinguished by checking the position of the wing 1237. The inner cylinder portion 1230 may be provided with a door that can be opened and closed between each pre-drying section, the coating section and the last drying section.

The pre-drying section is provided with a plurality of stirring wings 1233 for stirring the crushed coal injected. The stirring blade 1233 is formed by projecting inwardly to the inner surface of the inner cylinder portion 1230. The stirring blade 1233 is in contact with the drying air by a relatively large area and time by stirring in a manner of pumping the pulverized coal while rotating with the inner cylinder portion 1230 to improve the drying effect.

Like the pre-drying section, the final drying section is provided with a plurality of stirring vanes 1237 for stirring the pulverized coal. The stirring blade 1237 is formed by projecting inwardly to the inner surface of the inner cylinder portion 1230. The stirring vane 1237 rotates with the inner cylinder part 1230 to scoop up the pulverized coal into the air so as to be in contact with the dry air for more area and time, thereby improving the drying effect.

The inner cylinder portion 1230 is rotatably supported with respect to the outer cylinder portion 1250 disposed coaxially on the outside of the inner cylinder portion 1230. A bearing 1240 is installed between the outer cylinder portion 1250 and the inner cylinder portion 1230 such that the inner cylinder portion 1230 is rotatable with respect to the outer cylinder portion 1250. In addition, at least one driving roller part 1270 for rotating the outer cylinder part 1250 is installed on the inner wall of the outer cylinder part 1250. The driving roller is driven in contact with the outer surface of the inner cylinder portion 1230 so that the inner cylinder portion 1230 is rotated about an axis. To this end, the inner cylinder portion 1230 has a roller contact portion 1239 to facilitate contact friction with the drive roller 1270. Of course, the drive roller 1270 may be modified in various ways such as gear engagement or chain drive in addition to the contact friction drive method. The inner cylinder portion 1230 preferably has a rotation speed of between 10 and 100 RPM.

The outer cylinder part 1250 includes a dry air inlet part 1251 through which hot dry air is introduced and a dry air outlet part 1253 through which the dry air is discharged. Here, the dry air inlet 1251 and the dry air outlet 1253 may be disposed at positions spaced apart from each other with respect to the longitudinal direction of the outer cylinder 1250. That is, the gap is spaced apart so that the dry air introduced through the dry air inlet 1251 is not immediately discharged through the dry air outlet 1253 so that dry air is filled in the entire outer cylinder part 1250.

The outer cylinder portion 1250 has a coal receiving portion 1255 for receiving the pulverized coal finally dried at the discharge end portion 1238 side of the final drying section of the inner cylinder portion 1230. The coal receiver 1255 may include a separate heating device to remove moisture remaining in the pulverized coal. In addition, the outer cylinder part 1250 includes a dry coal supply passage 1256 to which the coal receiver 1255 and the boiler 130 are connected, and an open / close valve 1257 to open and close the dry coal supply passage 1256. The on-off valve 1257 may be opened when a predetermined amount of pulverized coal is accumulated in the coal receiving unit 1255.

The horizontal extension length of the inner cylinder portion 1230 and the outer cylinder portion 1250 according to the present invention can be designed to be longer than the ratio shown in FIG.

Coal drying unit 120 according to the present invention is disposed inclined downward so that the height position is lowered along the discharge end 1238 side in the input unit 1231, the discharge end from coal input unit 1231 by gravity It is preferable to be able to gradually move to the (1238) side. At this time, the inclination angle is preferably between 1 to 5 degrees.

The coal drying unit 120 having such a structure may effectively remove moisture contained in the pulverized coal supplied through the input unit 1231. That is, the dry air introduced through the dry air inlet 1125 passes through the inner cylinder part 1230 of the membrane material to dry the pulverized coal contained in the inner cylinder part 1230, and then the dry air outlet part 1253 together with moisture. The coal is dried through). And the coal drying unit 120 is to remove the moisture in the pre-drying section first and then coated with a hydrophobic material in the coating section and finally dried again to prevent the moisture is adsorbed to the dried coal again. Thus, the pulverized coal may be supplied to the boiler 130 in a dry state.

The boiler 130 burns the crushed coal supplied from the coal drying unit 120. Thermal energy generated by the coal burned in the boiler 130 is converted into electrical energy through kinetic energy. The coal-fired power generation system includes an electric power generation unit 140 for this energy conversion. The electric generator 140 includes a steam drum 141, a steam turbine 143, and a generator 145. The steam drum 141 is installed inside the boiler 130 to absorb thermal energy of the burned coal. The steam drum 141 includes steam, ie, water vapor vaporized by thermal energy obtained from the boiler 130. The steam in the steam drum 141 drives the steam turbine 143 while moving to the steam turbine 143 with high energy. And the generator 145 connected to the steam turbine 143 and the shaft converts the kinetic energy into electrical energy.

The steam passing through the steam turbine 143 moves to the condenser 150. The condenser 150 absorbs the energy of steam and condenses it into water. The capacitor unit 150 preferably absorbs the energy of steam by using low temperature water drawn from an external lake, river or sea. Water condensed by the condenser 150 is moved to the steam drum 141 again.

The coal-fired power generation system according to the present invention includes a hot air supply unit for heating the outside air in the condenser unit 150 to supply to the coal drying unit (120). The hot air supply unit is disposed in the suction unit 161 and the condenser unit 150 where the outside air is sucked, and the thermal energy obtaining unit 163 for allowing the sucked air to obtain thermal energy from steam, and the air obtained by the thermal energy is a coal drying unit. It has a hot air movement passage having a discharge portion 165 to be discharged to the (120) side. The hot air supply unit 160 has a blower 167 for blowing air sucked from the suction unit 161 to the discharge unit 165 through the heat energy acquisition unit 163. The discharge part 165 is connected to the dry air inlet part 1251.

As described with reference to the coal drying unit 120, the dry air supplied to the dry air inlet unit 1251 passes through the inner cylinder part 1230 made of membrane material, and then, dry the pulverized coal and then the dry air outlet unit 1253. Is discharged through. Accordingly, the coal drying unit 120 may dry a large amount of coal by obtaining some thermal energy from the waste heat without providing a separate heating device.

On the other hand, the coal-fired power generation system according to the present invention includes a collecting unit 210 for collecting the ash containing the coal briquettes from the steam and exhaust gas generated from the boiler 130. Here, the ash including the coal briquettes collected by the collecting unit 210 is stored in the silo 220, and steam and gas other than the ash are discharged through the flue gas denitrification and desulfurization facility.

Ash including the coal briquettes stored in the silo 220 is supplied to the coal briquette separation unit 230 continuously or intermittently. The coal briquette separation unit 230 separates the coal briquette powder from the ash including the coal briquette powder. The coal briquettes separated by the coal briquette separation unit 230 are transferred to the coal briquette storage unit 240, and the refined ash is transferred to the refined ash storage unit 250, respectively. The refined ash stored in the refined ash storage unit 250 is treated to be recycled when the content of the fine coal content (LOI) is less than 6%.

When the coal briquettes stored in the coal briquettes storage unit 240 are stored in a predetermined amount or more, the coal briquettes are transferred to the coal briquettes supply unit 260 for pelletizing the coal briquettes. The coal briquette storage unit 240 includes a check sensor to check a stored amount of the coal briquettes stored. The check sensor may be an infrared sensor or a physical sensor. Unburned coal powder separated from the ash can be unburned by rising from the inner wall surface of the boiler 130 which is relatively low in temperature when it is thrown into the boiler 130 and does not approach the center of the boiler 130 due to its small particle size. Because of this is to pelletize so that the central portion of the boiler 130 is accessible.

3 is a flow chart showing a method for pelletizing the coal briquette powder according to the present invention. As can be seen in Figure 3, the method for pelletizing the coal briquette powder according to the present invention is first mixed with the coal briquette powder and a binder in a stirring vessel (S10). Here, the binder adopts petroleum binders such as pitch, bitumen and asphalt. Rapeseed, coffee by-products, bark, pine cones, and lignin powder may be added together with the petroleum-based binder. In particular, coffee by-products are preferred as binder additives because of low water content and high calorific value. On the other hand, a starch-based binder can be adopted as the binder. The starch-based binder comprises starch-based polymer particles, reactive emulsifiers and water.

And the coal briquettes and the binder is stirred to mass (mass) (S20). As a result, the coal briquettes dispersed as small particles agglomerate with each other to increase the mass. At this time, it is preferable to add a certain amount of wood waste, such as sawdust. Wood waste has a relatively low ignition point and is easy to ignite, helping to completely burn unburned coal. On the other hand, wood waste may be replaced or a regular amount of coal powder may be added. The coal powder is to increase the coal content of the coal briquettes because unrefined ash is included in the coal briquettes separated from the coal briquette separation unit 230. The higher the coal content of the pellet, the higher the chance of complete combustion.

Next, the massed coal briquette powder is molded into pellets having a predetermined shape and size (S30). The molding may adopt an injection molding method or an extrusion molding method using an injection mold. In the case of extrusion molding, the massed coal briquette powder is extruded to a predetermined cross-sectional shape and diameter, and then cut into pellets by cutting into a predetermined length. At this time, it may be pelletized by drying for a predetermined time after extrusion and cutting or crushing to a predetermined length. Unburned coal pellets produced by injection molding can also be crushed if necessary to make the pellets smaller. Pelletized coal briquettes should preferably be as similar in size to pulverized coal as possible.

Pelletized coal briquettes are supplied to the coal crushing unit 110 and pulverized with the raw coal. The raw coal and the pelletized coal briquettes are crushed together and transferred to the coal drying unit 120. The process is as described above. Here, when the total water value of the ore coal supplied to the coal mill is 30% or more, the weight ratio of the coal briquettes to the coal mill, that is, the pelletized coal briquettes is 5 to 6% or more Be sure to The total moisture value of coal is the value obtained by drying the raw coal at 107 ° C. for 60 minutes and multiplying the measured weight by the initial weight of the raw coal and multiplying by 100. The coal-fired power generation system according to the present invention may further include a coal moisture measurement unit for measuring the total moisture of the coal supplied to the coal mill 110. On the other hand, a portion of the coal supplied to the coal crushing unit 110 may be taken as a sample to measure the total moisture.

When pulverized by adding 5 to 6% unburned coal powder by weight to raw coal having a high water content of 30% or more, coal drying is carried out later because the water contained in the coal is diffused into unburned coal and the overall moisture concentration is lowered. The drying efficiency in the part 120 can be improved. Pelletized coal briquettes have a lower ash efficiency than coal fuel because they contain ash, so that the supply amount of the coal briquettes needs to be appropriately limited so as not to put a load on the combustion efficiency of the coal fuel boiler. Of course, it is possible to change the weight ratio with coal according to the production properties of the pelletized coal briquettes.

4 is an explanatory view showing the coal briquette separation unit 230 for separating the coal briquette powder from the ash according to the present invention. As can be seen in Figure 4, the coal briquette separation unit 230 according to the present invention includes a casing (100a) having an ash supply passage to which the ash is supplied. Here, ash refers to ashes in which coal is burned in the boiler 130 of the coal-fired power plant, and includes unburned coal powder which is not completely burned. The ash including such coal briquettes is introduced into the casing 100a through the ash supply passage 110a.

The casing 100a has a lower coal briquette discharge passage 130a and a refined ash discharge passage 150a through which the refined ash from which the coal briquettes are separated from the ash is discharged. Here, the refined ash discharge passage 150a is installed to face the coal briquette discharge passage 130a at the upper side of the casing 100a. The lower portion of the casing (100a) is preferably a funnel shape in which the cross-sectional area in the horizontal direction decreases. Accordingly, the dropped coal briquettes may be easily discharged into the coal briquettes discharge passage 130a by force such as gravity.

The conductive ceramic filter 200a covering the inlet of the tablet ash discharge passage 150a is installed inside the casing 100a. The conductive ceramic filter 200a is porous, and the size of the through hole is preferably 75 to 85 micrometers or less. This is to block the coal briquettes according to the basic fact that the ash particles correspond to the coal briquettes when the ash particles are larger than a specific size (75 to 85 micrometers). The conductive ceramic filter part 200a may be made of a metal material for electrical conductivity or manufactured in a form including a separate metallic component.

The conductive ceramic filter part 200a has a plurality of plate surface parts 201a extending in parallel to each other in the longitudinal direction. Here, the plate surface portions 201a facing each other are designed to have different electrodes. That is, the plurality of plate surface portions 201a have electrodes in the order of (+), (-), (+), (-) in a predetermined direction. This is to separate according to the electrical properties difference between the relatively non-conductive coal briquettes and the refined ash that is not relatively conductive. Since the plurality of plate surface portions 201a are provided, the coal briquettes can be blocked and separated from the ash containing the coal briquettes in a relatively large area.

The coal briquette separation unit 230 according to the present invention includes a power supply unit for applying or releasing electricity to the conductive ceramic filter unit 200a. The power supply unit is preferably a DC power supply device, and it is preferable to adopt a device capable of applying a relatively high voltage.

The coal briquette separation unit 230 according to the present invention may include a moving unit 400a capable of moving the conductive ceramic filter unit 200a. The moving part 400a mediates the casing 100a and the conductive ceramic filter part 200a and allows the conductive ceramic filter part 200a to move relative to the casing 100a. The moving part 400a may shake off the ashes stuck in the through-holes of the conductive ceramic filter 200a using inertia by shaking the conductive ceramic filter 200a from side to side or up and down.

On the tablet ash discharge passage 150a, an air pressure adjusting unit 300a is installed to adjust the air pressure so that air flows from the inside of the casing 100a along the tablet ash discharge passage 150a. The air pressure control unit 300a may adopt any one of various pump types such as a reciprocating pump, a rotary pump, an axial pump, and the like. Atmospheric pressure control unit (300a) may have a second mesh to block the ash more than a certain size.

By such a structure, the coal briquette separation unit 230 according to the present invention is based on the particle size difference and the electrical conductivity difference from the ash including the coal briquettes supplied through the ash supply passage (110a). Separately, the coal briquettes may be discharged through the coal briquette discharge passage 130a positioned at the lower portion of the casing 100a, and the refined ash may be discharged along the refined ash discharge passage 150a located at the upper portion of the casing. can do.

5 is a flow chart illustrating a method for separating coal briquettes using the coal briquette separation unit 230 according to the present invention. Referring to Figure 5 with reference to Figure 4, the method for separating the coal briquettes using the coal briquette powder separation unit 230 according to the present invention, first, the electricity supply and air pressure control unit for the conductive ceramic filter (200a) ( 300a) to operate (S100).

Then, the ash containing the coal briquettes is supplied into the casing 100a through the ash supply passage 110a (S200). Then, the air containing the unburnt coal ash approaches the conductive ceramic filter part 200a because the air flow is directed toward the refined ash discharge passage 150a by the air pressure control unit 300a. In this case, since the plurality of plate portions 201a of the conductive ceramic filter portion 200a are supplied with electricity by the power supply portion, the conductive particles having electrical conductivity may be plated portion by the electric field of the plate portion 201a. It is led to an electrode such as 201a and spaced apart from the plate surface portion 201a by a predetermined distance. Accordingly, the coal briquette powder does not primarily contact the plate surface portion 201a, and even if it is in contact with the conductive ceramic filter portion 200a, 75 to 85 micrometers, which is the size of the through hole of the conductive ceramic filter portion 200a. More generally, because of the large size, the conductive ceramic filter 200a does not pass through and is blocked. Here, the air pressure control unit (300a) is to operate as weakly as possible to utilize the separation technology according to the difference in electrical conductivity between the coal briquettes and refined ash. On the other hand, the purification ash (Insulating particles) is charged with the electrode of the plate portion 201a and the electrode opposite to the plate portion 201a under the influence of the electric field when approaching the plate portion 201a receives the electricity supply. The refined ash attracted to the plate portion 201a is relatively small in size and moves along the refined ash discharge passage through the through hole.

Next, the operation of the air pressure control unit 300a is stopped (S300). In this case, since the electricity supply to the conductive ceramic filter 200a is still maintained, only the electric field formed by the gravity and the conductive ceramic filter part 200a is removed by the flow of air acting inside the casing. Accordingly, the purification ash (Insulating paticle) is attracted to the conductive ceramic filter portion 200a by the electric field of the conductive ceramic filter portion 200a and does not fall, and the coal briquettes (Conductive particles) as described above are conductive ceramic filters. Since it has a property of being spaced apart from the portion (200a), it will fall according to gravity. The dropped coal briquettes are moved along the coal briquette discharge passage.

Then, after a predetermined time, the electricity to the conductive ceramic filter unit 200a is released and the air pressure control unit 300a is reactivated (S400). Accordingly, the refined ash remaining inside the casing is moved along the refined ash discharge passage 150a through the through hole of the conductive ceramic filter 200a. Here, the purified ash adhered to the surface of the conductive ceramic filter part 200a by shaking the conductive ceramic filter 200a by using the moving part 400a. Can be moved accordingly.

Next, the operation of the air pressure control unit 300a is stopped again (S500). In this step, the operation of the air pressure control unit 300a is stopped to drop particles (refined ash or coal briquettes) caught on the conductive ceramic filter unit 200a. To this end, the conductive ceramic filter unit 200a may be shaken by using the moving unit 400a or the air pressure control unit 300a may be operated in reverse to allow air to flow from the purification ash discharge passage 150a into the casing. . In this case, it is preferable to block the ash supply passage 110a so that the flow of air flows along the coal briquette discharge passage 130a.

Claims (5)

In coal-fired power generation system,
A coal grinding unit for grinding coal;
A coal drying unit accommodating the pulverized coal and removing moisture of the coal;
A coal boiler for burning the pulverized coal dried in the coal drying unit;
An electric power generation unit installed inside the coal boiler and having a steam drum including steam for obtaining thermal energy generated by combustion of the pulverized coal, and a steam turbine connected to the steam drum;
A condenser unit for recovering thermal energy from the steam passing through the steam turbine to condense the steam;
A hot air flow passage having an intake unit through which external air is sucked in, a heat energy acquisition unit disposed inside the condenser unit, and an exhaust unit connected to the coal drying unit, and blowing the air sucked from the intake unit to the discharge unit side. It includes a hot air supply having a blower,
The coal drying unit,
An inner cylinder part formed of a membrane material through which the pulverized coal is extended and extends in the horizontal direction and the pulverized coal is blocked but the air is passed;
An outer cylinder portion having a dry air inlet portion connected to the discharge portion and a dry air outlet portion through which the air introduced from the dry air inlet portion is discharged, and which the inner cylinder portion is rotatably supported about the horizontal axis on an outer side of the inner cylinder portion; Wow;
A driving roller unit installed in the outer cylinder to provide a driving force so that the inner cylinder rotates about the horizontal axis;
The inner cylinder portion is pre-drying section, coating section and the final drying section are sequentially arranged along the moving direction of the crushed coal supplied through the input,
The coating section is provided with a coating spraying unit for injecting a hydrophobic coating agent to the pulverized coal in at least a portion of the inner cylinder portion, each of the pre-drying section and the final drying section is provided with a stirring blade for stirring the pulverized coal The pulverized coal is dried with stirring,
Coal-fired power generation system, characterized in that the stirring blade is formed to protrude inward to the inner surface of the inner cylinder portion. delete delete delete The method of claim 1,
The outer cylinder portion,
A coal receiver for receiving the pulverized coal at the discharge end of the inner cylinder;
A dry coal supply passage connecting the coal receiver and the coal boiler;
Coal-fired power generation system comprising an on-off valve for opening and closing the dry coal supply passage.

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