JP2011241050A - Facility and method for storing coal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide safer facility and method for storing coal.SOLUTION: According to the facility and the method for storing coal, a water sprayer 150 is disposed in a coal delivery path 140 on which coal is delivered from a storage tank 102 by a delivery machine 130 is transported. Thus, when the coal is delivered from the coal storage tank 102 by the delivery machine 130 is reloaded in the coal storage tank 102, water can be sprayed to the conveyed coal. By this water spraying, the heat of the coal is captured by water vaporization heat to reduce a temperature.

Description

  The present invention relates to a coal storage facility and a coal storage method for storing coal until it is used in a thermal power plant or the like.

  Thermal power plants obtain electric energy using coal, oil, natural gas or the like as fuel. Of these fuels, coal is often stored in a coal storage tank in a coal storage facility until it is combusted in a boiler after being transported. When stacked and stored, coal may generate heat due to the progress of oxidation reaction over time.

For this reason, in order to prevent coal stored for a long period of time, a plurality of coal storage tanks are provided inside the coal silo, the coal is stored separately in each storage tank, the storage date and time is memorized, and stored first. Coal is used first (so-called first-in first-out).
However, if the amount of coal stored increases, even if the first-in first-out is performed, the storage period of coal becomes long, and the temperature may rise before the order of use comes. For this reason, when a certain period of time has passed or when the temperature has risen, the coal is transshipped and air-cooled by conveying the coal (for example, see Patent Document 1).

JP 2007-45564 A

  However, even if the coal is transshipped and air-cooled by transporting the coal, the cooling may be insufficient. Insufficient cooling of coal is not preferable from the viewpoint of safety because the temperature immediately rises even after transshipment.

  An object of the present invention is to provide a safer coal storage facility and a coal storage method.

  The present invention solves the above problems by the following means.

(1) A coal storage facility of the present invention includes a plurality of coal storage tanks that are partitioned from each other and capable of storing coal therein, a coal receiving unit that is disposed above the plurality of coal storage tanks and receives coal, and the plurality of coal storage tanks A coal carry-in device for carrying the coal received above the coal receiving section into the plurality of coal storage tanks, and the coal arranged below the plurality of coal storage tanks and stored in the plurality of coal storage tanks. A payout device that pays out from below the coal storage tank, a coal carry-out passage that is arranged below the payout device and carries coal discharged by the payout device, and a coal carry-out passage that is arranged downstream of the coal carry-out passage A coal supply path for supplying the coal carried out to the external device, a coal return path that is arranged downstream of the coal carry-out path and returns the coal unloaded by the coal carry-out path to the coal receiving section, and the coal Depending on the carry-out route A transport path switching unit that switches the transport path of the coal to be discharged to the coal supply path side or the coal return path side; and a watering device that sprays the coal that is disposed in the coal transport path and is transported through the coal transport path. Prepare.

  According to the coal storage facility, since the watering device is arranged in the coal carry-out path, water can be sprinkled on the coal to be transported. The sprinkled coal has its heat lowered by the heat of vaporization of water or when the amount of water is large, the heat is taken away by running water and the temperature is lowered.

(2) Moreover, the said coal storage facility is a storage part which memorize | stores the time of coal carrying in in which the coal in each of these some coal storage tanks was carried in, and the coal storage tank which passed predetermined time from the time of coal carrying in memorize | stored in the said memory | storage part A transshipment control unit that controls the dispensing device, the coal return path, the transport path switching unit, the coal receiving unit, and the coal carry-in device so as to transship the coal stored in a predetermined coal storage tank; A watering device control unit that controls the watering device to spray water on the coal transported through the coal carry-out path when the coal is transshipped by the transshipment control unit.

  According to the coal storage facility, the coal is sprayed only when the coal is transshipped. For this reason, the coal that is supplied to the external device and burned is not sprinkled, and a reduction in coal combustion efficiency (power generation efficiency) is prevented.

(3) Furthermore, a plurality of carbon monoxide concentration measuring units provided in each of the plurality of coal storage tanks,
A plurality of temperature measuring units provided in each of the plurality of coal storage tanks, and the transshipment control unit is configured to measure a carbon monoxide concentration of a predetermined value or more by the plurality of carbon monoxide concentration measuring units. Or when a temperature equal to or higher than a predetermined value is measured by the plurality of temperature measuring units, stored in a coal storage tank in which a carbon monoxide concentration higher than a predetermined value is measured, or a coal storage tank in which a temperature higher than a predetermined value is measured You may control the said discharge device, the said coal return path, the said conveyance path switching part, the said coal receiving part, and the said coal carrying-in apparatus so that the made coal may be transshipped to a predetermined coal storage tank.
According to this, since the transshipment of coal is performed when the carbon monoxide concentration or temperature of the coal storage tank becomes high, the safety of the coal storage facility is improved.

(4) The transshipment control unit may circulate coal in the coal storage tank that has paid out of the plurality of coal storage tanks.
According to this coal storage facility, when coal is transshipped, it is returned to the originally stored storage tank, so that the efficiency of management of coal stored in a plurality of storage tanks can be improved.

(5) The coal storage method of the present invention includes a plurality of coal storage tanks that are partitioned from each other and capable of storing coal therein, a coal receiving unit that is disposed above the plurality of coal storage tanks and receives coal, and the plurality of coal storage tanks. A coal carry-in device that carries coal received in the coal receiving unit disposed above the coal receiving unit, and a storage unit that stores the time when the coal is carried into each of the coal storage tanks, Dispensing device that disposes the coal stored below the plurality of coal storage tanks and stored in the plurality of coal storage tanks from below the coal storage tank, and coal disposed below the dispensing device and dispensed by the dispensing device A coal unloading path, a coal supply path that is disposed downstream of the coal unloading path and supplies coal unloaded by the coal unloading path to an external device, and a coal unloading path that is disposed downstream of the coal unloading path. By carry-out route A coal return path for returning the unloaded coal to the coal receiving section, a transport path switching section for switching a coal transport path carried out by the coal unloading path to the coal supply path side or the coal return path side, and the coal A watering device for spraying the coal that is disposed in the carry-out path and transported through the coal carry-out path, and a storage unit that stores the time when the coal is loaded in each of the plurality of coal storage tanks. So that the coal stored in the coal storage tank that has passed for a predetermined time from the time of coal delivery stored in is transferred to the predetermined coal storage tank, the dispensing device, the coal return path, the transport path switching unit, the coal receiving unit, and The said coal carrying-in apparatus is controlled, and when the coal is transshipped, the said watering apparatus is controlled so that the coal conveyed through the said coal carrying-out path is sprinkled.

  According to this coal storage method, as in the above (1), since the watering device is arranged in the coal carry-out path, water can be sprinkled on the coal being conveyed. The sprinkled coal has a cooling effect that is enhanced by the heat of vaporization of water, so that the temperature of the coal is lowered. Also, as in (2) above, since water is sprayed only when coal is transshipped, it is not sprinkled on coal that is supplied to an external device and burned, and coal combustion efficiency (power generation efficiency) ) Reduction is prevented.

  According to the present invention, a safer coal storage facility and a coal storage method can be provided.

It is a figure which shows the relationship between the coal silo in a thermal power plant, a boiler, a turbine, and a generator. It is a figure which shows the coal storage equipment containing a coal silo and the surrounding coal conveyance apparatus. It is a figure explaining the hopper for coal carrying out provided in the lower part of the coal silo, a discharging machine, and a hopper lower conveyor. It is a block diagram of the conveyance control system of a coal storage facility. It is a flowchart which shows the external supply control of a conveyance control apparatus. It is a flowchart which shows the overall control including the coal transshipment control of coal. It is a flowchart which shows coal transshipment control.

  Hereinafter, a coal storage facility for a thermal power plant according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a relationship among a coal silo 4, a boiler 7, turbines 10, 11, 12 and generators 13, 14 in a thermal power plant. In addition, other equipment in the thermal power plant is omitted for easy understanding of the figure. The coal transported to the thermal power plant by the coal ship 1 is landed on the silo line conveyor 4A from the coal ship 1 by the continuous type coal unloader (unloader) 2 and is transported to the coal silo 4 until it is actually used. Temporarily stored.

  After storage in the coal silo 4, the coal is conveyed to the bunker 5 by the bunker row conveyor 4B. The coal transported to the bunker 5 is made into powder (pulverized coal) by the high-performance pulverized coal machine 6 and put into the boiler 7. The pulverized coal is combusted in the boiler 7 to convert the feed water 8 into steam 9 having high-temperature (for example, about 600 degrees) thermal energy. The steam 9 is converted into mechanical energy by the high-pressure turbine 10 and the intermediate-pressure turbine 11 to rotate them, and the generator 13 connected thereto is driven to generate electrical energy. Further, the residual heat is guided to the low-pressure turbine 12, and the generator 14 connected thereto is also driven.

  FIG. 2 is a diagram illustrating an example of the coal storage facility 100 including the coal silo 4 and the surrounding coal conveyance device. The coal silo 4 is surrounded by an outer wall 101.

  As shown in FIG. 2, the coal storage area of the coal silo 4 is divided into three rows of A, B, and C in the horizontal direction (Y direction in FIG. 2) (the symbols A, B, and C are on the roof of the outer wall 101). Each row is further divided into four parts a, b, c, and d in the vertical direction (X direction in FIG. 2) (the symbols of a, b, c, and d are shown in the lower part of the side surface of the outer wall 101). A total of 12 coal storage tanks 102 are provided. In addition, the number of the coal storage tanks 102 is not limited to this, It may be more or less.

  The partition walls forming each coal storage tank 102 include a main pillar 104 extending in the vertical direction (Z direction), and a plurality of intermediate pillars 105 that are narrower than the main pillar 104 extending in the vertical direction (Z direction) between adjacent main pillars 104 and horizontal. Directional ring beam 106.

  The coal storage facility 100 includes a receiving conveyor (coal receiving unit) 20 (20A, 20B, 20C) that receives the coal carried by the silo row conveyor 4A and transports the coal to the coal storage tank 102. The receiving conveyor 20A conveys coal to the A row coal storage tank 102, the receiving conveyor 20B conveys the coal to the B row coal storage tank 102, and the receiving conveyor 20C conveys the coal to the C row coal storage tank 102. Moreover, the receiving conveyor 20 is connected with the loading machine (coal carrying-in apparatus) 108 (108A, 108B, 108C) provided in the upper part of the coal storage tank 102, respectively. The loading machine 108A is connected to the receiving conveyor 20A, the loading machine 108B is connected to the receiving conveyor 20B, and the loading machine 108C is connected to the receiving conveyor 20C. The loader 108 can move in the vertical direction (X direction in the figure) on each coal storage tank 102, and can drop coal into one of the coal storage tanks 102.

  FIG. 3 is a view for explaining a coal hopper 110, a dispenser 130 (dispensing device), and a hopper lower conveyor (coal carrying path) 140 provided at the lower part of the coal storage tank 102. A hopper generally means a funnel for flowing coal or the like, that is, a funnel-like device. In this embodiment, the hopper 110 is installed in the lower part of each coal storage tank 102. The hopper 110 includes a hopper wall configured in a lattice shape. Of the hopper walls 111, 112, 113, 114... Extending in the vertical direction (X direction in the figure), the odd-numbered hopper walls 111, 113,. And the lower part of the coal storage tank 102 has the space of the inverted trapezoid shape into which coal is poured into the bottom part by adjacent odd-numbered hoppers. In this space, even-numbered hopper walls 112, 114... Are arranged, and a gap 133 is formed below the even-numbered hopper wall with the bottom of the hopper. Dispenser 130 that can move along 112, 114... Is installed. Further, the hopper walls 121, 122, 123... Extend in the lateral direction, and the strength of the vertical hopper walls 111, 112, 113, 114... Is secured and positioned by these lateral hopper walls 121, 122, 123. ing.

  The dispenser 130 includes a rotating member 131 having six claw members each having an arc shape and extending radially. As described above, the rotating member 131 is movable along the hopper walls 112, 114, and so on so that the claw members are disposed in the gaps 133 in the gaps 133 of the even-numbered hopper walls 112, 114, and so on. Is provided. Further, a slit 132 is provided at the bottom of the even-numbered hopper walls 112, 114... In the hopper 110 along the moving direction of the dispenser 130.

  Below the slit 132, a lower hopper conveyor 140 is installed. The dispenser 130 moves along the even-numbered hopper walls 112, 114... Inside the coal stored in the hopper while rotating the rotating member 131. As a result, the coal is discharged from the gap 133, passes through the slit 132, and is discharged to the lower hopper conveyor 140.

  Returning to FIG. 2, the lower hopper conveyor 140 extends to the outside of the coal storage tank 102 (X plus direction in the figure). And in the vicinity of the conveyance end point of the lower hopper conveyor 140, a watering device 150 for watering the conveyed coal is provided.

  One sprinkler 150 is provided for each lower hopper conveyor 140. The watering device 150 is a water pipe that spans over the upper part of the lower hopper conveyor 140 that extends to the outside of the coal silo 4. A plurality of holes are formed in a portion of the water pipe located above the lower hopper conveyor 140. From the hole, it is possible to spray water as appropriate to the coal that is the object to be conveyed passing under the control of the control unit, which will be described later, and the coal is water-cooled by this watering.

  A primary payout conveyor (coal carry-out path) 160 is arranged in the horizontal direction (Y direction in FIG. 2) below the conveyance end point of the lower hopper conveyor 140, and the coal discharged to the lower hopper conveyor 140 is the primary payout conveyor. It is passed to 160. A secondary delivery conveyor (coal delivery path) 161 provided perpendicular to the primary delivery conveyor 160 is disposed at the conveyance end point of the primary delivery conveyor 160. The coal carried out by the primary delivery conveyor 160 is converted by 90 degrees in the moving direction by the secondary delivery conveyor 161, and is conveyed in the X minus direction in FIG.

  A transport path switching unit 162 is provided at the transport end point of the secondary payout conveyor 161. The conveyance path switching unit 162 sends a coal transported from the secondary delivery conveyor 161 to the bunker 5 to be burned outside the coal storage facility 100, that is, in the boiler 7, in accordance with an instruction from the control device described later. (Coal supply path) 4B is switched over or switched to the recirculation conveyor 163 (coal return path) for storage in the coal storage tank 102 again.

  The recirculation conveyor 163 extends from the transfer path switching unit 162 and is connected to the receiving conveyor 20 so as to reload coal into the coal storage tank 102.

  Next, the conveyance control system 200 of the coal storage facility 100 will be described. FIG. 4 is a block diagram showing the transport control system 200. The conveyance control system 200 includes a monitoring device 210 that monitors the state of coal, a coal conveyance device 220 that moves coal, and a control device 230 that controls the monitoring device 210 and the coal conveyance device 220.

  The monitoring device 210 includes a timer 211 that measures the storage period of coal, and a storage period storage unit 212 that is connected to the timer 211 and stores the storage period of coal. When coal in each coal storage tank 102 is carried in (including transshipment), time measurement by the timer 211 is started, and the storage period data being timed is sent to the storage period storage unit 212. The storage period storage unit 212 sends storage period data to the control device 230.

  The monitoring device 210 includes a temperature sensor 213 that detects the temperature of the stored coal, and a temperature monitoring unit 214 that is connected to the temperature sensor 213 and monitors the temperature of the stored coal. The temperature sensors 213 are installed at six locations at the same horizontal position at the top of the hopper 110 and at six different horizontal positions within the coal storage tank 102 above the top of the hopper 110 for each coal storage tank 102. (Both not shown). The temperature data detected by the temperature sensor 213 is transmitted to the temperature monitoring unit 214. The temperature monitoring unit 214 sends this temperature data to the control device 230 together with data indicating which coal storage tank 102 is the temperature sensor 213.

  Furthermore, the monitoring device 210 includes a gas sensor 215 installed in each coal storage tank 102 and a gas concentration monitoring unit 216 that is connected to the gas sensor 215 and monitors the gas concentration. The gas sensor 215 can measure the CO concentration, and is installed at three locations at equal intervals in the Y direction at the top of the hopper 110 and at one location inside the coal storage tank 102 for each coal storage tank 102. Furthermore, one is installed in the upper part of the silo as a whole (none is shown).

  The CO gas concentration data detected by the gas sensor 215 is transmitted to the gas concentration monitoring unit 216. The gas concentration monitoring unit 216 sends the CO gas concentration data to the control device 230 together with data indicating which gas sensor 215 of which coal storage tank 102.

  The control device 230 includes a conveyance control unit (reloading control unit) 231 and a watering control unit 232. The transport control unit 231 sends coal to the outside based on the storage period data from the storage period storage unit 212, the temperature data from the temperature monitoring unit 214, and the CO gas concentration data from the gas concentration monitoring unit 216, or transships ( Controls whether recirculation is performed.

  The watering control unit 232 controls the watering device 150 to perform watering when the conveyance control unit 231 determines to perform transshipment.

  The control device 230 may be a normal computer, and includes at least a CPU having an arithmetic function, a ROM storing a computer program for executing recirculation control, a RAM as a work area, a storage period storage unit 212, a temperature monitor. Unit 214, gas concentration monitoring unit 216, and input / output control device connected to coal conveying device 220, and a monitor (all not shown).

  The coal conveyance device 220 is a device that sends coal to the outside or recirculates the coal based on the control of the conveyance control unit 231 described above. The coal conveyance device 220 includes the above-described dispenser 130, the lower hopper conveyor 140, the primary delivery conveyor 160, the conveyance path switching unit 162, the bunker line conveyor 4B, the recirculation conveyor 163, the receiving conveyor 20, and the conveying unit including the loading machine 108. The whole thing.

  Next, the operation | movement performed with the coal storage equipment 100 of this embodiment is demonstrated.

(First-in first-out)
First, a first-in first-out operation that is a basic operation in the above-described coal storage facility 100 will be described. In order to shorten the average storage period of coal in the coal storage tank 102 as much as possible, in principle, the coal is transferred into and out of the storage tank 102 by “first-in first-out”.

  The new coal carried by the silo row conveyor 4 </ b> A is guided to the coal storage tank 102 of the coal silo 4 by the receiving conveyor 20, dropped into the tank by the loader 108, and stored in the coal storage tank 102.

  When the storage is started in the coal storage tank 102, the timer 211 starts counting. The storage period of coal is managed by the storage period storage unit 212 based on the time measured by the timer 211. Then, when using coal (when supplied to the outside and combusted in the boiler), the control device 230 uses the storage period managed by the storage period storage unit 212 as the most coal in the storage tank 102 in the storage period. Control is performed to supply (hereinafter, this control is referred to as external supply control).

FIG. 5 is a flowchart showing external supply control of the control device 230.
In step 101 (hereinafter, step is represented by S), the control device 230 operates the dispenser 130 installed below the hopper 25 in the coal storage tank 102 having a long storage period described above. As a result, the rotating member 131 of the dispenser 130 rotates, and the coal is delivered to the lower hopper conveyor 140 from the slit 132 formed under each coal storage tank 102.

  In S <b> 102, the lower hopper conveyor 140 is operated to transport the coal that has fallen onto the lower hopper conveyor 140. In this case, the watering device 150 does not operate. In S103, the primary delivery conveyor 160 and the secondary delivery conveyor 161 are operated. The coal transported by the lower hopper conveyor 140 is transferred to the primary delivery conveyor 160 and then transported by the secondary delivery conveyor 161.

  In S104, the conveyance control unit 231 connects the secondary delivery conveyor 161 and the bunker row conveyor 4B in the conveyance path switching unit 162, and operates the bunker row conveyor 4B in S105. Thereby, the coal carried by the secondary delivery conveyor 161 is carried out to the outside, that is, carried on the bunker row conveyor 4 </ b> B, carried to the bunker 5, and burned in the boiler 7.

Thus, according to the first-in first-out method of this embodiment, it is carried out from the coal storage tank 102 with a long storage period, and also from the coal stored previously also in the same coal storage tank 102 outside. Moreover, in this case, the watering device 150 does not operate and watering is not performed on the coal.
Therefore, since the water supplied to the external device and burned is not sprinkled, it is possible to prevent a reduction in combustion efficiency (power generation efficiency) of the coal supplied to the outside.

(Transshipment)
Next, the coal transshipment operation will be described. FIG. 6 is a flowchart showing overall control including coal transshipment control. FIG. 7 is a flowchart showing the coal transshipment (recirculation) control.

  First, the coal is transported by the receiving conveyor 20 and dropped into the coal storage tank 102 by the loading machine 108 and stored. When the storage is started in the coal storage tank 102, the timer 211 starts counting. The storage period of coal is managed by the storage period storage unit 212 based on the time measured by the timer 211. The above is the same as in the first-in first-out case.

  As shown in FIG. 6, the control device 230 first reads storage period data from after storage of coal from the storage period storage unit 212 in S201.

  In S202, it is determined whether or not the storage period exceeds the first period (1.5 months in the present embodiment). If not exceeded (S202, No), the process proceeds to S203. If it exceeds (S202, Yes), it will progress to S211 mentioned later, and the control apparatus 230 will perform the transshipment control shown in FIG. 7 so that the coal storage equipment 100 may transship coal.

  In the transshipment control of FIG. 7, the dispenser 130 installed in the lower part of the hopper 25 in the coal storage tank 102 is operated in S301 similarly to the external supply control of the transport control unit 231. As a result, the rotating member 131 of the dispenser 130 rotates, and the coal is delivered to the lower hopper conveyor 140 from the slit 132 formed under each coal storage tank 102. In S302, the lower hopper conveyor 140 is operated to transport the coal on the lower hopper conveyor 140.

  Next, in S303, unlike the external supply control, the watering device 150 is operated. As a result, water is sprayed from the hole of the water sprinkler 150 and water is applied to the coal.

  In S304, the primary delivery conveyor 160 and the secondary delivery conveyor 161 are operated. The coal that has been transported by the lower hopper conveyor 140, sprinkled and moistened is transferred to the primary delivery conveyor 160, and then transported by the secondary delivery conveyor 161.

  In S <b> 305, the conveyance control unit 231 connects the secondary delivery conveyor 161 and the recirculation conveyor 163 in the conveyance path switching unit 162. Thereby, coal is conveyed by the recirculation conveyor 163, and is conveyed to the receiving conveyor 20. FIG. The temperature of coal is lowered by heat of vaporization while being transported through the primary delivery conveyor 161, the secondary delivery conveyor 161, and the recirculation conveyor 163.

  In S <b> 306, the control device 230 operates the recirculation conveyor 163 and the receiving conveyor 20. The coal carried by the recirculation conveyor 163 is also carried to the loader 108 and returned to the original coal storage tank 102 in the same manner as the newly loaded coal carried by the silo line conveyor 4A. In addition, when returning to the original coal storage tank 102, there exists an advantage that the efficiency of management of the stored coal can be aimed at. However, it is not limited to this, and can be returned to another coal storage tank 102.

  In this embodiment, the coal is sprinkled with water. For this reason, when coal is conveyed by the primary delivery conveyor 160, the secondary delivery conveyor 161, and the recirculation conveyor 163, heat is taken away by the vaporization heat of water, and temperature falls.

  Even if the “first-in first-out” order does not occur, when the storage period exceeds a certain period, the transshipment of coal is performed for the following reason.

  In the present embodiment, in principle, the above-mentioned “first-in first-out” is adopted in the use of coal, and the old coal in the coal storage tank 102 is put out first to shorten the average coal storage period. However, when the amount of coal stored increases, the storage period becomes longer, and when stored for a long time, the temperature of coal may increase. For this reason, when storing beyond the first period (for example, 1.5 months), which is a certain period after coal is brought in, it is once transported on the conveyor even if the order of use has not yet come. This is because it is preferable to air-cool.

  Thus, the temperature of coal can be lowered | hung by moving the storage coal whose temperature rose by the belt conveyor. Coal does not generate heat in the absence of air at all, so it does not generate heat, but it is most likely to generate heat with a slight flow of air. However, if it is transported using a conveyor or the like and brought into contact with a large amount of air, the amount of heat dissipated becomes larger than the amount of heat generated by coal, and the temperature of coal decreases. Therefore, the coal which has been stored in the silo and once heated is discharged outside the silo using a conveyor and is recirculated back into the silo for air cooling. Furthermore, in this embodiment, since the watering apparatus 150 is operated, it is sprinkled by coal and the temperature of coal can be reduced.

  In addition, the 1.5 months adopted as the first period in the present embodiment are the coal heating temperature actual value of the applicant's Ishikawa Thermal Power, the coal with a high heating rate at the Misumi power station (for example, Blair sole charcoal) ) Is the value obtained from the actual temperature rise value.

  Returning to FIG. 6, if the storage period does not exceed 1.5 months in S202, the process proceeds to S203. In S <b> 203, the control device 230 reads temperature data from the temperature monitoring unit 214 together with data indicating which temperature sensor 213 of which coal storage tank 102.

  In S204, it is determined whether or not the hopper top temperature th exceeds a first temperature (for example, 45 degrees). If exceeded, the process proceeds to S211. If not, the process proceeds to S205. In S205, it is determined whether or not the silo internal temperature ts exceeds a second temperature (for example, 55 degrees). If exceeded, the process proceeds to S211. If not, the process proceeds to S206.

  Thus, the hopper top temperature th and the silo internal temperature ts are measured for the following reason.

  As described above, when stored for a long period of time, the temperature of the coal may increase. In S202, it is determined whether or not the first period has been exceeded. However, even if it does not exceed the first period, the coal temperature may increase. For this reason, the hopper top temperature th is monitored, and when the temperature reaches 45 degrees (Celsius, the same applies hereinafter), the process proceeds to S211 and transshipment is performed. Even if the hopper top temperature th does not become 45 degrees, when the silo internal temperature ts becomes 55 degrees, the process proceeds to S211 and the transshipment is performed.

  The reason why the first temperature at the hopper top temperature th is 45 degrees and the second temperature at the silo internal temperature ts is 55 degrees is as follows.

  As the properties of the stored coal, when it reaches the oxidation start temperature (about 60 degrees), it enters the low temperature oxidation zone and gradually begins to heat up, and when it reaches the evaporation start temperature (about 70 degrees), the low temperature oxidation zone ends and the coal moisture gradually increases. Evaporation begins, and when it reaches a red hot start temperature (about 85 ° C.), the coal moisture evaporates, and when it is left standing, it quickly becomes red hot.

  The hopper top temperature th is a temperature measured by thermometers (for example, six points) installed at a plurality of locations on the top. The hopper top temperature in the coal stored in the coal storage tank 102 is generally lower than the internal temperature of the coal storage tank 102. For this reason, the hopper top temperature th is set to 45 degrees as a warning temperature before the internal temperature of the coal storage tank 102 reaches the red heat start temperature, the evaporation start temperature, and the red heat start temperature.

  The silo internal temperature ts is a temperature obtained by measuring the coal temperature with a plurality of (for example, five points) wire thermometers suspended inside the coal inside the silo tank. 55 degree | times which is 2nd temperature is the temperature calculated | required from the temperature rise of coal in the time required for transshipment (recirculation) with respect to the red hot start temperature of coal, and the transshipment time.

  Returning to FIG. 6, if the silo internal temperature ts does not exceed 55 degrees in S205, the process proceeds to S206. In S206, the CO gas concentration data is read from the gas concentration monitoring unit 216 together with the data indicating which gas sensor of which coal storage tank 102.

  In S207, it is determined whether or not the CO gas concentration exceeds a first concentration (5 ppm in this embodiment) indicating the start of oxidation. If exceeded, the process proceeds to S208, the monitoring is strengthened, and the process further proceeds to S09. If not, the process proceeds directly to S209.

  In S208, monitoring for coal heat generation is strengthened. Surveillance refers to monitoring within the silo, and monitors the 12 tanks sequentially using an ITV (industrial television) (not shown) at a fixed time every day, and further monitors once a day. The patrol. In S209, the confirmation work in the tank by the ITV and the patrol frequency of the monitoring staff are performed more frequently.

  In S209, it is determined whether or not the CO gas concentration exceeds the second concentration (20 ppm in this embodiment) that requires immediate transshipment. If it exceeds, the process proceeds to S211. If not, the process returns to S201.

  The first concentration of 5 ppm is a detection limit concentration of the gas sensor 215, and is a concentration that indicates that the oxidation of coal has begun to a slight extent. If 5 ppm is detected, the monitoring reinforcement system is entered here. The second CO concentration of 20 ppm is a CO concentration indicating that oxidation of coal is taking place in earnest from past performance data. When 20 ppm is detected, coal reloading is started immediately.

  Coal temperature rise initially occurs locally rather than uniformly in stored coal, and then the temperature rise gradually spreads. Therefore, it may not be possible to reliably detect an increase in the temperature of coal by simply measuring ten thousand tons of coal per tank using a thermometer for temperature monitoring.

  However, coal always generates carbon monoxide (CO) as the temperature rises. Since CO is lighter than air, it collects at the top of the coal silo. Therefore, by installing the gas sensor 215 on the upper part of the coal storage tank 102 and monitoring the CO concentration, local heat generation of coal can be detected at an early stage.

  The gas sensor 215 for measuring the CO concentration is installed in advance in the coal silo 4 in response to a request from the Industrial Safety Law for ensuring safety to the human body, and uses this.

  In S212, it is determined whether or not the coal transshipment has been completed. If not completed, the process returns to S211, and the coal transshipment operation is continued. If completed, the process returns to S201.

  As described above, according to the coal storage facility 100 and the coal storage method of the present embodiment, when the coal is transshipped, the watering device 150 is operated. As a result, the heat of the coal is lost due to the heat of vaporization of water, and the temperature drops. Therefore, the safety of the coal storage facility can be enhanced.

  In addition, water is sprayed on coal only when coal is transshipped. For this reason, it is not sprinkled on the coal which is supplied to the external device and burned, and it is possible to prevent the combustion efficiency (power generation efficiency) of the coal from being lowered. Since coal transshipment is performed when a certain period of time elapses in the coal storage tank, when the carbon monoxide concentration becomes high, or when the temperature becomes high, the safety of the coal storage facility can be improved.

  As described above, various modifications and changes are possible without being limited to the embodiments described above, and these are also within the scope of the present invention.

  4: Coal silo, 4B: Bunker row conveyor, 20 (20A, 20B, 20C): Receiving conveyor, 100: Coal storage facility, 102: Coal storage tank, 108: Loading machine, 110: Hopper, 130: Dispenser, 140 : Hopper lower conveyor, 150: sprinkler, 160: primary delivery conveyor, 161: secondary delivery conveyor, 162: transport path switching unit, 163: recirculation conveyor, 210: monitoring device, 212: storage period storage unit, 213: Temperature sensor, 214: Temperature monitoring unit, 215: Gas sensor, 216: Gas concentration monitoring unit, 230: Control device, 231: Transport control unit, 232: Sprinkling control unit

Claims (5)

A plurality of coal storage tanks partitioned from each other and capable of storing coal inside;
A coal receiving portion disposed above the plurality of coal storage tanks for receiving coal;
A coal carry-in device for carrying coal that is disposed above the plurality of coal storage tanks and received by the coal receiving unit into the plurality of coal storage tanks;
A payout device that disposes the coal stored below the plurality of coal storage tanks and stored in the plurality of coal storage tanks from below the coal storage tanks;
A coal unloading path for unloading the coal disposed below the dispensing device and dispensed by the dispensing device;
A coal supply path that is arranged on the downstream side of the coal carry-out path and supplies the coal carried out by the coal carry-out path to an external device;
A coal return path that is disposed downstream of the coal carry-out path and returns the coal unloaded by the coal carry-out path to the coal receiving unit;
A transport path switching unit that switches the transport path of the coal transported by the coal transport path to the coal supply path side or the coal return path side;
A coal storage facility comprising: a watering device that sprays water on the coal that is disposed in the coal carrying-out path and is transported through the coal carrying-out path. A storage unit for storing the time when coal is loaded into each of the plurality of coal storage tanks;
The dispensing device, the coal return path, the transport path switching unit, the coal so as to reload the coal stored in the coal storage tank that has passed for a predetermined time from the time of coal delivery stored in the storage unit into the predetermined coal storage tank A transshipment control unit for controlling the receiving unit and the coal carry-in device;
The coal storage according to claim 1, further comprising a watering device control unit that controls the watering device so as to spray water on the coal transported through the coal carry-out path when the coal is reloaded by the transshipment control unit. Facility. A plurality of carbon monoxide concentration measuring units provided in each of the plurality of coal storage tanks;
A plurality of temperature measuring units provided in each of the plurality of coal storage tanks,
The transshipment control unit is configured such that when the carbon monoxide concentration of a predetermined value or more is measured by the plurality of carbon monoxide concentration measurement units, or when the temperature of a predetermined value or more is measured by the plurality of temperature measurement units. The discharging device, the coal, so that coal stored in a coal storage tank in which a carbon monoxide concentration of a predetermined value or more is measured, or coal stored in a coal storage tank in which a temperature of a predetermined value or more is measured is transferred to the predetermined storage tank The coal storage facility according to claim 2, which controls a return path, the transport path switching unit, the coal receiving unit, and the coal carry-in device.   4. The coal storage facility according to claim 2, wherein the transshipment control unit circulates coal in a coal storage tank that has been paid out of the plurality of coal storage tanks. A plurality of coal storage tanks partitioned from each other and capable of storing coal inside;
A coal receiving portion disposed above the plurality of coal storage tanks for receiving coal;
A coal carry-in device for carrying coal that is disposed above the plurality of coal storage tanks and received by the coal receiving unit into the plurality of coal storage tanks;
A storage unit for storing the time when coal is loaded into each of the plurality of coal storage tanks;
A payout device that disposes the coal stored below the plurality of coal storage tanks and stored in the plurality of coal storage tanks from below the coal storage tanks;
A coal unloading path for unloading the coal disposed below the dispensing device and dispensed by the dispensing device;
A coal supply path that is arranged on the downstream side of the coal carry-out path and supplies the coal carried out by the coal carry-out path to an external device;
A coal return path that is disposed downstream of the coal carry-out path and returns the coal unloaded by the coal carry-out path to the coal receiving unit;
A transport path switching unit that switches the transport path of the coal transported by the coal transport path to the coal supply path side or the coal return path side;
A watering device for spraying the coal disposed in the coal carrying-out path and transported through the coal carrying-out path;
A storage unit for storing the coal loading time when the coal in each of the plurality of coal storage tanks is loaded,
The dispensing device, the coal return path, the transport path switching unit, the coal so as to reload the coal stored in the coal storage tank that has passed for a predetermined time from the time of coal delivery stored in the storage unit into the predetermined coal storage tank Controlling the receiving unit and the coal carrying-in device;
A coal storage method for controlling the water sprinkler to spray water on the coal transported through the coal carry-out path when the coal is transshipped.

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