JP2015117844A - Superheater and boiler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce temperature difference of superheated steam flowing from heat transfer tubes to an outlet header in a superheater and a boiler.SOLUTION: A superheater includes: an inlet header 81 to which steam is supplied; an outlet header 82 from which generated superheated steam is discharged; a plurality of heat transfer tubes 83 aligned in a longitudinal direction of the inlet header 81 and the outlet header 82 so as to couple the inlet header 81 to the outlet header 82; a water injection device 91 that can inject cooling water to the steam supplied to the inlet header 81; and a water-injection-quantity regulator that can regulate a water injection quantity in the longitudinal direction of the inlet header 81 by controlling the water injection device 91.

Description

  The present invention relates to a superheater capable of generating superheated steam in a boiler that generates steam by burning solid fuel and air, and a boiler having a superheater.

  In a thermal power plant, for example, a coal-fired boiler has a furnace that has a hollow shape and is installed in a vertical direction, and combustion burners are arranged in a plurality of stages in the vertical direction on the furnace wall. And the furnace 11 is provided with the flue in the upper part, and the superheater, reheater, and economizer for recovering the heat | fever of waste gas are provided in this flue. Therefore, heat is exchanged between the exhaust gas generated by combustion in the furnace and the water flowing in the heat transfer tube, steam can be generated, and power can be generated by supplying this steam to the steam turbine and driving it. It has become.

  As such a boiler, there exists a thing described in the following patent document, for example.

Japanese Patent Laid-Open No. 50-065939 Japanese Patent Laid-Open No. 10-299424 JP 07-233903 A JP 2006-071166 A

  In the conventional boiler, the water supplied by the feed water pump is preheated by the economizer, then supplied to each heat transfer tube on the furnace wall, and is overheated in the heat transfer tube to become saturated steam. This saturated steam is introduced into the superheater and is superheated by the exhaust gas to become superheated steam, and this superheated steam is supplied to the steam turbine. Since this superheater needs to supply superheated steam having a predetermined temperature to the steam turbine, an overheat reducer is provided that adjusts the temperature of the superheated steam by injecting water into the superheated steam.

  By the way, the superheater is configured by connecting an inlet header and an outlet header by a plurality of heat transfer tubes. And the temperature and flow velocity of the exhaust gas flowing through the flue differ, for example, between the vicinity of the wall surface and the central portion. For this reason, the superheater has a deviation in the amount of heat absorbed in the superheated steam flowing inside each heat transfer pipe, and even if the superheat reducer injects water into the inlet communication pipe, the superheated steam at the outlet of the superheater Even if the average temperature can be reduced, the temperature difference between the tubes may not be reduced.

  If the temperature deviation of the superheated steam cannot be reduced by the superheat reducer, high-temperature parts will be created partially, and high-grade materials with excellent heat resistance strength will be created for the inlet header, outlet header, and heat transfer tube in the superheater. It must be used, leading to high costs. The use of a high-grade material only in a partially generated high-temperature part may vary depending on the operating state (boiler load, fuel type, etc.), and therefore it is difficult to predict in advance. Further, when the temperature of the superheated steam is increased, the maximum temperature of the outlet pipe header and the heat resistance temperature of the superheater pipe outlet may become a bottleneck, and the overall average steam temperature may not be increased.

  This invention solves the subject mentioned above, and it aims at providing the superheater and boiler which can reduce the temperature difference of the superheated steam which flows out from a heat exchanger tube to an outlet header.

  In order to achieve the above object, a superheater according to the present invention connects an inlet header to which steam is supplied, an outlet header for discharging generated superheated steam, and the inlet header and the outlet header. A plurality of heat transfer tubes arranged in the longitudinal direction of the inlet header and the outlet header, a water injection device capable of injecting cooling water to the steam supplied to the inlet header, and the water injection A water injection amount adjusting device capable of adjusting the water injection amount in the longitudinal direction of the inlet header by controlling the device.

  Therefore, when the steam supplied to the inlet header flows through the plurality of heat transfer tubes to the outlet header, the steam is superheated by recovering heat from the outside and being overheated. At this time, the water injection device adjusts the temperature of the superheated steam by injecting cooling water to the steam supplied to the inlet header, and the water injection amount adjusting device is configured to perform water injection in the longitudinal direction of the inlet header. Adjust the amount. Therefore, even if there is a deviation in the amount of heat recovered by the heat transfer tubes, each superheat that flows from each heat transfer tube to the outlet header is adjusted by adjusting the steam temperature supplied to each heat transfer tube according to the deviation in the heat amount. The temperature of the steam can be made uniform, and the temperature difference of the superheated steam flowing out from the heat transfer tube to the outlet header can be reduced.

  In the superheater of the present invention, the water injection device has a plurality of injection nozzles arranged at predetermined intervals in a longitudinal direction of the inlet header, and the water injection amount adjustment device is configured to supply water by the plurality of injection nozzles. It is characterized in that the injection amount can be adjusted.

  Therefore, by adjusting the water injection amount by the plurality of injection nozzles, the steam temperature supplied to each heat transfer tube is adjusted, and the outlet of each superheated steam flowing out from each heat transfer tube to the outlet header with a simple configuration. The temperature can be made uniform easily.

  In the superheater of the present invention, a plurality of injection nozzles are arranged in the inlet header.

  Therefore, since the temperature of the steam is adjusted by injecting the cooling water into the steam in the inlet header, the spray nozzle is not exposed to the outside, and the structure can be simplified.

  In the superheater of the present invention, a plurality of steam communication pipes for supplying steam are connected at a predetermined interval in the longitudinal direction of the inlet header, and the plurality of injection nozzles are respectively disposed in the steam communication pipes. Yes.

  Therefore, since the temperature of the steam is adjusted by injecting the cooling water into the steam in each steam communication pipe that supplies the steam, the temperature of the steam can be finely adjusted, and highly accurate temperature management can be performed.

  In the superheater of the present invention, the water injection amount adjusting device includes a flow rate adjusting valve provided in each cooling water supply pipe to the plurality of injection nozzles.

  Therefore, the temperature of the steam can be accurately adjusted by adjusting the opening of the flow rate adjusting valve and adjusting the injection amount of the cooling water from the injection nozzle.

  In the superheater of the present invention, the water injection amount adjusting device is configured such that the nozzle diameters of the plurality of injection nozzles or the pipe diameters of the cooling water supply pipes to the plurality of injection nozzles are different. It is a feature.

  Therefore, by adjusting the injection amount of the cooling water from the injection nozzle by changing the nozzle diameter of the injection nozzle or the diameter of the cooling water supply pipe, it is not necessary to provide a separate adjustment device, and the structure can be simplified. it can.

  In the superheater according to the present invention, the water injection device has an injection nozzle capable of injecting cooling water in a longitudinal direction of the inlet header.

  Therefore, since the injection nozzle injects the cooling water in the longitudinal direction of the inlet header, the cooling water can be spread over a wide range with a small number of nozzles.

  A boiler according to the present invention is provided in a furnace having a hollow shape and installed in a vertical direction, a combustion apparatus that blows fuel into the furnace, and a flue of the furnace to recover heat of exhaust gas. And the superheater that generates superheated steam.

  Therefore, exhaust gas is generated by injecting fuel into the furnace and burning it, and the superheater recovers the heat of the exhaust gas and generates superheated steam. At this time, even if there is a deviation in the amount of heat recovered by the plurality of heat transfer tubes, each flow from the heat transfer tubes to the outlet header is adjusted by adjusting the steam temperature supplied to each heat transfer tube according to the deviation in the heat amounts. The temperature of the superheated steam can be made uniform, and the temperature difference of the superheated steam flowing out from the heat transfer tube to the outlet header can be reduced. As a result, the average steam temperature at the boiler outlet can be increased without using high-grade materials for the superheater pipe, the reheater pipe, and the outlet header, and the plant efficiency can be improved.

  According to the superheater and boiler of the present invention, a water injection device capable of injecting cooling water to the steam supplied to the inlet header, and a water injection amount in the longitudinal direction of the inlet header by controlling the water injection device Is provided with a water injection amount adjusting device that can adjust the temperature of each superheated steam that flows from the plurality of heat transfer tubes to the outlet header, and reduces the temperature difference of the superheated steam that flows from the heat transfer tubes to the outlet header. be able to.

Drawing 1 is a schematic structure figure showing the boiler of a 1st embodiment. FIG. 2 is a schematic diagram of a steam system representing the flow of steam in the boiler. FIG. 3 is a schematic diagram illustrating a superheater. FIG. 4 is a schematic diagram illustrating an overheat reducer in the superheater. FIG. 5 is a graph showing a temperature change in the inlet header. FIG. 6 is a graph showing the temperature change of superheated steam. FIG. 7 is a schematic diagram illustrating the superheater according to the second embodiment. FIG. 8 is a schematic diagram illustrating the superheater according to the third embodiment. FIG. 9 is a schematic diagram illustrating the superheater according to the fourth embodiment.

  Exemplary embodiments of a superheater and a boiler according to the present invention will be described below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment, and when there are two or more embodiments, what comprises combining each embodiment is also included.

[First Embodiment]
FIG. 1 is a schematic configuration diagram showing a boiler according to the first embodiment, and FIG. 2 is a schematic diagram of a steam system showing a flow of steam in the boiler.

  The boiler according to the first embodiment is a boiler that can use pulverized coal obtained by pulverizing coal as fuel, burn the pulverized coal with a combustion burner, and recover heat generated by the combustion. In addition, this invention is not limited to this type of boiler, You may use fuels other than pulverized coal as a fuel.

  In the first embodiment, as shown in FIG. 1, the boiler 10 is a conventional boiler and includes a furnace 11 and a combustion device 12. The furnace 11 has a rectangular hollow shape and is installed along the vertical direction. The furnace wall constituting the furnace 11 is constituted by a heat transfer tube.

  The combustion device 12 is provided in a lower part of a furnace wall (heat transfer tube) constituting the furnace 11. This combustion apparatus 12 has a plurality of combustion burners 21, 22, 23, 24, 25 mounted on the furnace wall. In this embodiment, the combustion burners 21, 22, 23, 24, and 25 are arranged as four sets at equal intervals along the circumferential direction, and five sets along the vertical direction. Five stages are arranged. The shape of the furnace, the number of combustion burners in one stage, and the number of stages are not limited to this embodiment.

  The combustion burners 21, 22, 23, 24, 25 are connected to pulverized coal machines (mills) 31, 32, 33, 34, 35 via pulverized coal supply pipes 26, 27, 28, 29, 30. Although not shown, the pulverized coal machines 31, 32, 33, 34, and 35 are supported in a housing so that the pulverization table can be driven to rotate with a rotation axis along the vertical direction, and face the upper side of the pulverization table. A plurality of crushing rollers are configured to be rotatably supported in conjunction with the rotation of the crushing table. Accordingly, when coal is introduced between a plurality of crushing rollers and a crushing table, the pulverized coal supplied to the pulverized coal supply pipe 26 is pulverized to a predetermined size and classified by transporting air (primary air). 27, 28, 29, 30 can be supplied to the first combustion burners 21, 22, 23, 24, 25.

  In the furnace 11, a wind box 36 is provided at the mounting position of each combustion burner 21, 22, 23, 24, 25, and one end of an air duct 37 is connected to the wind box 36. The duct 37 has a blower 38 attached to the other end. Therefore, the combustion air (secondary air) sent by the blower 38 is supplied from the air duct 37 to the wind box 36 and supplied from the wind box 36 to the combustion burners 21, 22, 23, 24, 25. it can.

  In addition, each combustion burner 21, 22, 23, 24, 25 which constitutes the combustion apparatus 12 of the present embodiment has an oil nozzle capable of injecting oil fuel at the center and a fine fuel mixture outside the oil nozzle. A fuel nozzle capable of injection, a secondary air nozzle capable of injecting secondary air to the outside of the fuel nozzle, and a tertiary air nozzle capable of injecting tertiary air to the outside of the secondary air nozzle. Yes. Therefore, when the boiler is started, each combustion burner 21, 22, 23, 24, 25 injects oil fuel into the furnace 11 to form a flame, and thereafter, the pulverized fuel mixture, secondary air, and tertiary air are supplied. It is injected into the furnace 11 to form a flame.

  Further, the furnace 11 is provided with an additional air injection device 41 above the mounting positions of the combustion burners 21, 22, 23, 24, 25, and the branched air branched from the air duct 37 to the additional air injection device 41. The ends of the duct 42 are connected. Therefore, the combustion air (secondary air) sent by the blower 38 can be supplied from the branch air duct 42 to the additional air injection device 41.

  As shown in FIG. 1, a furnace 11 has a flue 50 connected to an upper portion thereof, and superheaters (superheaters) 51 and 52 for collecting heat of exhaust gas as a convection heat transfer section in the flue 50. Further, reheaters 53 and 54 and economizers 55, 56 and 57 are provided, and heat exchange is performed between the exhaust gas generated by combustion in the furnace 11 and water.

  The flue 50 is connected to an exhaust gas pipe 58 from which exhaust gas subjected to heat exchange is discharged downstream. The exhaust gas pipe 58 is provided with an air heater 59 between the air duct 37 and performs heat exchange between the air flowing through the air duct 37 and the exhaust gas flowing through the exhaust gas pipe 58, and the combustion burners 21, 22, 23, The temperature of the combustion air supplied to 24 and 25 can be raised.

  Although not shown, the exhaust gas pipe 58 is provided with a denitration device, an electrostatic precipitator, an induction blower, and a desulfurization device, and a chimney is provided at the downstream end.

  When the pulverized coal machines 31, 32, 33, 34, and 35 are driven in the coal-fired boiler 10 configured as described above, the supplied coal is pulverized, and the generated pulverized coal is supplied by the air for conveyance. It is supplied to the first combustion burners 21, 22, 23, 24, 25 through the pipes 26, 27, 28, 29, 30. Also, heated combustion air is supplied from the air duct 37 to the combustion burners 21, 22, 23, 24, 25 via the wind box 36.

  Then, the combustion burners 21, 22, 23, 24, and 25 blow the first pulverized fuel mixture, which is a mixture of pulverized coal and carrier air, into the combustion region A of the furnace 11 and the combustion air into the combustion region of the furnace 11. A first flame swirl is formed in the combustion region A by blowing into A and igniting at this time. Further, the additional air injection device 41 blows additional air above the first flame swirl flow and the reduction region B in the furnace 11 to perform combustion control. In the furnace 11, when the pulverized fuel mixture and the combustion air are combusted to generate a flame swirl flow, and a flame swirl flow is generated in the combustion region A, the combustion gas (exhaust gas) rises while swirling in the furnace 11. To the reduction region B.

  At this time, in the furnace 11, the combustion burners 21, 22, 23, 24, and 25 are set so that the supply amount of air is less than the theoretical air amount with respect to the supply amount of pulverized coal. The reduction region B above A is maintained in a reducing atmosphere. Therefore, NOx generated by the combustion of the pulverized fuel mixture is reduced in the reduction region B. The additional air injection device 41 blows additional air above the reduction region B in the furnace 11. Then, in the reduction region B, the exhaust gas reacts with the additional air, whereby the oxidative combustion of the pulverized fuel is completed, and the amount of NOx generated by the combustion of the pulverized fuel is reduced.

  The water supplied from a water supply pump (not shown) is preheated by the economizers 55, 56, and 57, then supplied to a steam drum (not shown) and supplied to each water pipe (not shown) on the furnace wall. It is heated to become saturated steam and fed into a steam drum (not shown). Further, saturated steam of a steam drum (not shown) is introduced into the superheaters 51 and 52 and is superheated by the combustion gas. The superheated steam generated by the superheaters 51 and 52 is supplied to a power plant (not shown) such as a turbine. Further, the steam taken out in the middle of the expansion process in the turbine is introduced into the reheaters 53 and 54, overheated again, and returned to the turbine. In addition, although the furnace 11 was demonstrated as a drum type | mold (steam drum), it is not limited to this structure.

  Thereafter, the exhaust gas that has passed through the economizers 55, 56, and 57 of the flue 50 is subjected to removal of harmful substances such as NOx by a catalyst in a denitration device (not shown) in the exhaust gas pipe 58, and the particulate matter is collected by an electric dust collector. Is removed, and after the sulfur content is removed by the desulfurizer, it is discharged from the chimney into the atmosphere.

  Here, the flow of water and steam in the boiler 10 described above will be described. As shown in FIG. 2, the water supply line 61 is provided with a water supply pump 62 and a steam drum 63, and the downstream portion is connected to a heat transfer tube 64 that constitutes the furnace wall of the furnace 11. The heat transfer tube 69 has a downstream portion connected to the steam line 65, superheaters 51 and 52 are provided in the steam line 65, and an overheat reducer 66 is provided between the superheaters 51 and 52. The steam line 65 is connected to a high-pressure turbine 67 a in the steam turbine 67 and is connected to a low-pressure turbine 67 b via reheaters 53 and 54. The steam turbine 67 is connected to a discharge line 68, provided with economizers 55, 56, and 57, and connected to a water supply line 61.

  Therefore, when the feed water pump 62 is driven, a predetermined amount of water is supplied from the feed water line 61 to the heat transfer pipe 64 via the steam drum 63, and is heated by exchanging heat in the boiler, thereby generating steam. The steam is superheated by the superheaters 51 and 52 and adjusted in temperature by the superheat reducer 66, and then supplied to the high-pressure turbine 67a via the steam line 65 to drive the high-pressure turbine 67a to generate power. The steam that has worked in the high-pressure turbine 67a is superheated by the reheaters 53 and 54, supplied to the low-pressure turbine 67b, and drives the low-pressure turbine 67b to generate power. The steam that has worked in the low-pressure turbine 67 b is superheated by the economizers 55, 56, and 57 through the discharge line 68 and then returned to the water supply line 61.

  Hereinafter, the superheaters 51 and 52 and the superheat reducer 66 will be described. FIG. 3 is a schematic diagram illustrating a superheater, and FIG. 4 is a schematic diagram illustrating a superheat reducer in the superheater.

  As shown in FIG. 3, the superheater 51 has an inlet header 71, an outlet header 72, and a plurality of heat transfer tubes 73. The inlet header 71 is connected to the downstream end of a steam pipe 74 that supplies steam from a steam line 65 (see FIG. 2). The outlet header 72 is connected to an upstream end of a steam communication pipe 75 that discharges the generated superheated steam and supplies it to the superheater 52. The plurality of heat transfer tubes 73 are arranged in the longitudinal direction of the inlet header 71 and the outlet header 72 so as to connect the inlet header 71 and the outlet header 72.

  The superheater 52 has substantially the same configuration as the superheater 51 and includes an inlet header 81, an outlet header 82, and a plurality of heat transfer tubes 83. The inlet header 81 is connected to the downstream end of the steam communication pipe 75 of the superheater 51. The outlet header 82 is connected to an upstream end of a steam discharge pipe 84 that discharges superheated superheated steam. The plurality of heat transfer tubes 83 are arranged in the longitudinal direction of the inlet header 81 and the outlet header 82 so as to connect the inlet header 81 and the outlet header 82.

  3 and 4, the inlet headers 71 and 81 and the outlet headers 72 and 82 of the superheaters 51 and 52 are arranged up and down, and both are connected by a plurality of linear heat transfer tubes 83. Although shown, this configuration is a simplified representation of the actual configuration. Actually, the inlet headers 71 and 81 and the outlet headers 72 and 82 of the superheaters 51 and 52 are arranged in parallel, and both of them are U-shaped (not limited to this, there are W-shaped and the like). They are connected by a heat pipe 83.

  The superheat reducer 66 is provided in the inlet header 81 of the superheater 52, cools the steam supplied from the steam communication pipe 75 to the inlet header 81, lowers the temperature, and consequently reduces the outlet steam temperature. Is. As shown in FIG. 4, the superheat reducer 66 is configured by a water injection device 91 that can inject cooling water to the steam supplied to the inlet header 81.

  The water injection device 91 has a plurality (five in this embodiment) of injection nozzles 92a, 92b, 92c, 92d, and 92e arranged at predetermined intervals in the longitudinal direction of the inlet header 81. The plurality of injection nozzles 92 a, 92 b, 92 c, 92 d, and 92 e are arranged in the inlet header 81, and for example, injection ports are arranged in the radial direction, that is, toward the plurality of heat transfer tubes 83.

  The cooling water supply line 93 has a base end portion connected to a water supply source (not shown) and a tip end portion branched into a plurality of (in this embodiment, five) branch pipes 94a, 94b, 94c, 94d, 94e, The spray nozzles 92a, 92b, 92c, 92d, and 92e are connected. The cooling water supply line 93 is provided with a water supply pump 95, and the branch pipes 94a, 94b, 94c, 94d, 94e are provided with flow rate adjusting valves 96a, 96b, 96c, 96d, 96e. The water supply pump 95 is an example, and a bypass pipe from the boiler water supply pump may be connected to the cooling water supply line 93 without providing the water supply pump 95 in the cooling water supply line 93.

  On the other hand, each heat transfer tube 83 is provided with temperature sensors 97a, 97b, 97c for measuring the temperature of the heat transfer tube 83 or the temperature of the internal steam. In the present embodiment, temperature sensors 97a, 97b, and 97c are provided on the heat transfer tube 83 connected to each end of the outlet header 88 and the heat transfer tube 83 connected to the center portion. However, the position where the temperature sensor is provided is not limited to this embodiment, and four or more positions may be provided, or may be provided for all the heat transfer tubes 83.

  The control device 98 receives the measurement results of the temperature sensors 97a, 97b, and 97c, and adjusts the opening degree of the flow rate adjusting valves 96a, 96b, 96c, 96d, and 96e based on the measurement results. That is, in the furnace 11 and the flue 50 (see FIG. 1), the exhaust gas temperature, the exhaust gas flow rate, and the like differ between the wall portions or the central portion depending on the shape and the like. Generally, the temperature of the exhaust gas at the center is high. Therefore, even if the superheater 52 has a deviation in the amount of heat absorption in the superheated steam flowing inside each heat transfer tube 83 and the water injection device 91 injects water into the inlet header 81, the heat transfer tube 83 exits the outlet tube. There is a possibility that the deviation of the outlet temperature of the superheated steam flowing out to the pool 82 cannot be reduced. Therefore, in the present embodiment, the water injection device 91 injects different amounts of water in the longitudinal direction of the inlet header 81 in advance corresponding to the heat absorption amount deviation of the superheated steam flowing through each heat transfer tube 83. The temperature deviation of the superheated steam can be reduced.

  Note that the superheater 52 of this embodiment has a water injection amount adjustment device that can adjust the water injection amount in the longitudinal direction of the inlet header 81 by controlling the water injection device 91 that constitutes the overheat reducer 66. doing. This water injection amount adjusting device includes a plurality of injection nozzles 92a, 92b, 92c, 92d, and 92e, a plurality of branch pipes 94a, 94b, 94c, 94d, and 94e, and a plurality of flow rate adjusting valves 96a, 96b, 96c, and 96d. , 96e and the like.

  Next, the operation of the superheaters 51 and 52 and the superheat reducer 66 will be described. When the steam supplied from the steam pipe 74 to the inlet header 71 of the superheater 51 moves to the outlet header 72 through the plurality of heat transfer tubes 73, it is superheated by recovering the heat of the external exhaust gas. The steam superheated by the superheater 51 is sent to the superheater 52 through the steam communication pipe 75. When the steam supplied to the inlet header 81 of the superheater 52 moves to the outlet header 82 through the plurality of heat transfer tubes 83, it is superheated by recovering the heat of the external exhaust gas.

  The superheat reducer 66 causes the spray nozzles 92 a, 92 b, 92 c, 92 d, and 92 e of the water injection device 91 to inject cooling water to the steam in the inlet header 81, thereby reducing the temperature of the steam. At this time, the control device 98 adjusts the opening degree of the flow rate adjusting valves 96a, 96b, 96c, 96d, and 96e based on the measurement results of the temperature sensors 97a, 97b, and 97c. That is, the control device 98 estimates the temperature distribution in the plurality of heat transfer tubes 83 from the detection results of the temperature sensors 97a, 97b, and 97c. And the control apparatus 98 increases the amount of cooling water injected from the corresponding injection nozzle 92a, 92b, 92c, 92d, 92e with respect to the area | region of the inlet header 81 to which the heat exchanger tube 83 with high temperature was connected. That is, the opening degree of the flow rate adjusting valves 96a, 96b, 96c, 96d, and 96e corresponding to the injection nozzles 92a, 92b, 92c, 92d, and 92e that increase the cooling water is increased.

  The control device 98 detects the temperature distribution in the plurality of heat transfer tubes 83 by the temperature sensors 97a, 97b, and 97c, and then supplies the amount of cooling water to the area of the inlet header 81 to which the high temperature heat transfer tubes 83 are connected. Although it is made to increase, it is not limited to this control. That is, the control device 98 estimates the temperature distribution in the plurality of heat transfer tubes 83, and injects nozzles 92a, 92b, 92c, and 92d corresponding to the region of the inlet header 81 to which the heat transfer tubes 83 having a low temperature are connected. , 92e may reduce the amount of cooling water injected. Further, the control device 98 increases the amount of cooling water injected from the corresponding injection nozzles 92a, 92b, 92c, 92d, and 92e in the region of the inlet header 81 to which the heat transfer pipe 83 having a high temperature is connected. The amount of cooling water injected from the corresponding injection nozzles 92a, 92b, 92c, 92d, and 92e may be reduced in the region of the inlet header 81 to which the low temperature heat transfer tube 83 is connected.

  Whether to increase or decrease the amount of cooling water injected from the injection nozzles 92a, 92b, 92c, 92d, 92e varies depending on the temperature of the superheated steam discharged from the superheater 52. The superheated steam discharged from the superheater 52 is sent to the steam turbine 67 (see FIG. 2). However, it is necessary to send superheated steam at a predetermined temperature to the steam turbine 67. The temperature of the superheated steam is adjusted by increasing / decreasing the amount of injection from each of the injection nozzles 92a, 92b, 92c, 92d, 92e. Therefore, the control device 98 adjusts the total amount of cooling water injected from the injection nozzles 92a, 92b, 92c, 92d, and 92e based on the measurement result of a temperature sensor (not shown) provided in the steam discharge pipe 84. In this case, finally, after all the superheated steam flowing out from the heat transfer tube 83 to the outlet header 82 has joined, the mixed average temperature reaches the final target temperature, so that the high temperature heat transfer tube 83 reaches the final target temperature. Adjust the increase in the amount of water jetted and the amount of water jetted down to the pipe with lower temperature.

  Then, the steam that has moved to the outlet header 82 through the plurality of heat transfer tubes 83 becomes superheated steam and is discharged to the steam discharge tube 84.

  Here, the temperature change of the steam in the superheaters 51 and 52 and the superheat reducer 66 will be described. FIG. 5 is a graph showing the temperature change in the inlet header, and FIG. 6 is a graph showing the temperature change of the superheated steam.

  As indicated by the solid line in FIG. 5, when steam is supplied from the steam pipe 74 to the inlet header 71 of the superheater 51 at the place P1, the heat of the exhaust gas is recovered while passing through the plurality of heat transfer pipes 73. The temperature starts to rise due to overheating. As the steam is discharged from the heat transfer tubes 73 to the outlet header 72 at the place P2, the temperature rise is completed. Then, when the steam is sent to the inlet header 81 of the superheater 52 through the steam communication pipe 75, the superheat reducer 66 causes the water injection device 91 to inject the cooling water, so that the temperature of the steam decreases. At the place P3, the steam in the inlet header 81 recovers the heat of the exhaust gas while passing through the plurality of heat transfer pipes 73 and is overheated, so that the temperature rise starts. As the steam is discharged from each heat transfer tube 83 to the steam discharge tube 84 at the place P4, the temperature rise is completed. Here, the temperature Tt is an appropriate temperature of the superheated steam sent to the steam turbine 67 (see FIG. 2).

  However, when temperature deviation occurs in the plurality of heat transfer pipes 73 in the superheater 52, even if water is injected into the steam communication pipe 75 as in the prior art, as shown by the dotted line in FIG. To the place P3, a heat transfer tube 83 is generated in which the temperature of the superheated steam cannot be reduced. Then, the temperature rises more than necessary between the place P3 and the place P4 while the steam passes through a part of the heat transfer tubes 73 having a high heating temperature, and exceeds the appropriate temperature Tt of the superheated steam. For example, since the heat transfer tube 83 has an exhaust gas temperature distribution and a flow velocity distribution in the width direction, the heat absorption amount is different for each heat transfer tube 83, and thus a temperature deviation occurs.

  That is, in FIG. 6, conventionally, water is injected into the steam communication pipe 75, so that the temperature Ta at the inlet header 81 is uniformly distributed in the longitudinal direction of the inlet header 81, as indicated by a dashed line. It becomes. Therefore, when a high heat absorption amount deviation occurs in the center portion of the plurality of heat transfer tubes 73, the temperature Tb of the steam flowing from the heat transfer tube 83 into the outlet header 82 is not high in the longitudinal center portion of the outlet header 82. A uniform distribution results in a partially high steam temperature. On the other hand, in FIG. 6, since this embodiment injects the cooling water of the quantity corresponding to temperature distribution to each heat exchanger tube 73 in the longitudinal direction of the inlet header 81 as represented by a solid line dashed line, the inlet pipe Even if the heat absorption amount deviation occurs in the plurality of heat transfer tubes 36, the temperature Tb at the outlet header 82 remains at the outlet tube, even if the temperature Ta at the header 81 becomes lower in the longitudinal center of the inlet tube header 81. The distribution is uniform in the longitudinal direction of the stopper 82, and the steam temperature is not partially increased.

  As described above, in the superheater of the first embodiment, the inlet header 81 to which steam is supplied, the outlet header 82 for discharging the generated superheated steam, and the inlet header 81 and the outlet header 82 are connected. A plurality of heat transfer tubes 83 arranged in the longitudinal direction of the inlet header 81 and the outlet header 82, and a water injection device 91 capable of injecting cooling water to the steam supplied to the inlet header 81, A water injection amount adjusting device capable of adjusting the water injection amount in the longitudinal direction of the inlet header 81 by controlling the water injection device 91 is provided.

  Therefore, when the steam supplied to the inlet header 81 in the superheater 52 flows to the outlet header 82 through the plurality of heat transfer tubes 83, the steam is recovered from the outside and is superheated to be superheated. It becomes. At this time, the water injection device 91 of the superheat reducer 66 adjusts the temperature of the superheated steam by injecting cooling water to the steam supplied to the inlet header 81, and the water injection amount adjusting device The water injection amount in the longitudinal direction of the gather 81 is adjusted. Therefore, even if there is a deviation in the amount of heat collected by the plurality of heat transfer tubes 83, the steam temperature supplied to each heat transfer tube 83 is adjusted according to the deviation in the amount of heat, so that the outlet header 82 from each heat transfer tube 83. The temperature of each superheated steam flowing through the heat transfer pipe 83 can be made uniform, and the temperature difference of the superheated steam flowing out from the heat transfer pipe 83 to the outlet header 82 can be reduced.

  In the superheater of the first embodiment, the water injection device 91 is provided with a plurality of injection nozzles 92a, 92b, 92c, 92d, and 92e arranged at predetermined intervals in the longitudinal direction of the inlet header 81. The water injection amount by the plurality of injection nozzles 92a, 92b, 92c, 92d, and 92e can be adjusted. Therefore, by adjusting the water injection amount by the plurality of injection nozzles 92a, 92b, 92c, 92d, and 92e, the steam temperature supplied to each heat transfer tube 83 is adjusted, and each heat transfer tube 83 can be configured with a simple configuration. The outlet temperature of each superheated steam flowing out to the outlet header 82 can be easily made uniform.

  In the superheater of the first embodiment, a plurality of injection nozzles 92 a, 92 b, 92 c, 92 d, 92 e are arranged in the inlet header 81. Therefore, since the temperature of the steam is adjusted by injecting the cooling water into the steam in the inlet header 81, the injection nozzles 92a, 92b, 92c, 92d, and 92e are not exposed to the outside of the inlet header 81. It is possible to simplify the structure.

  In the superheater of the first embodiment, as the water injection amount adjusting device, the flow rate adjusting valves 96a, 96b are provided in the branch pipes 94a, 94b, 94c, 94d, 94e to the plurality of injection nozzles 92a, 92b, 92c, 92d, 92e. 96c, 96d, and 96e. Therefore, by adjusting the opening of the flow rate adjusting valves 96a, 96b, 96c, 96d, 96e and adjusting the injection amount of the cooling water by the injection nozzles 92a, 92b, 92c, 92d, 92e, fine temperature adjustment of the steam can be performed. It can be carried out.

  Moreover, in the boiler of 1st Embodiment, the furnace 11 which makes | forms a hollow shape and is installed along a perpendicular direction, the combustion apparatus 12 which injects a fuel toward the furnace 11, and the flue 50 of the furnace 11 Are provided with superheaters 51 and 52 for recovering the heat of exhaust gas and generating superheated steam.

  Therefore, the combustion device 12 blows a fuel gas, which is a mixture of solid fuel and combustion air, into the furnace 11 and burns it to generate exhaust gas. The superheaters 51 and 52 recover the heat of the exhaust gas. Generate superheated steam. At this time, even if there is a deviation in the amount of heat collected by the plurality of heat transfer tubes 83, the temperature of the steam supplied to each heat transfer tube 83 is adjusted in advance according to the deviation in the amount of heat, and the outlet from each heat transfer tube 83. The temperature of each superheated steam flowing in the header 82 can be made uniform, and the temperature difference of the superheated steam flowing out from the heat transfer tube 83 to the outlet header 82 can be reduced. As a result, the average steam temperature at the boiler outlet can be increased without using high-grade materials for the superheater pipe, the reheater pipe, and the outlet header, and the plant efficiency can be improved.

[Second Embodiment]
FIG. 7 is a schematic diagram illustrating the superheater according to the second embodiment. In addition, the same code | symbol is attached | subjected to the member which has the same function as embodiment mentioned above, and detailed description is abbreviate | omitted.

  In the second embodiment, as shown in FIG. 7, the superheater 52 includes an inlet header 81, an outlet header 82 (see FIG. 3), and a plurality of heat transfer tubes 83, and the inlet pipe of the superheater 52. A superheat reducer 101 is provided in the header 81, and the superheat reducer 101 cools the steam supplied from the steam communication pipe 75 to the inlet header 81 and lowers the temperature. The superheat reducer 101 is configured by a water injection device 102 that can inject cooling water to the steam supplied to the inlet header 81.

  The water injection device 102 has a plurality of (in this embodiment, five) injection nozzles 103a, 103b, 103c, 103d, and 103e arranged at predetermined intervals in the longitudinal direction of the inlet header 81. The plurality of injection nozzles 103a, 103b, 103c, 103d, and 103e are arranged in the inlet header 81, and the injection ports are arranged toward the plurality of heat transfer tubes 83.

  The cooling water supply line 93 is branched at its distal end into a plurality of branch pipes 94a, 94b, 94c, 94d, and 94e, and is connected to the injection nozzles 103a, 103b, 103c, 103d, and 103e. The cooling water supply line 93 is provided with a water supply pump 95 and a flow rate adjusting valve 104.

  The superheater 52 of this embodiment has a water injection amount adjustment device that can adjust the water injection amount in the longitudinal direction of the inlet header 81 by controlling the water injection device 102 that constitutes the superheat reducer 101. Yes. This water injection amount adjusting device includes a plurality of injection nozzles 103a, 103b, 103c, 103d, and 103e, a plurality of branch pipes 94a, 94b, 94c, 94d, and 94e. Here, the water injection amount adjusting device is configured such that the nozzle diameters of the plurality of injection nozzles 103a, 103b, 103c, 103d, and 103e are different depending on the amount of heat absorption of the superheater tube in the vicinity of the nozzles. Is done. For example, the nozzle diameters of the injection nozzles 103a and 103e are small, and the nozzle diameters of the injection nozzles 103b, 103c, and 103d are large.

  Instead of the nozzle diameters of the plurality of injection nozzles 103a, 103b, 103c, 103d, and 103e, the pipe diameters of the plurality of branch pipes 94a, 94b, 94c, 94d, and 94e are changed, or fixed types such as orifices are used. An aperture mechanism may be provided.

  Accordingly, the superheat reducer 101 lowers the temperature of the steam by injecting the cooling water to the steam in the inlet header 81 by the spray nozzles 103a, 103b, 103c, 103d, and 103e of the water spray device 102. . At this time, since the nozzle diameters of the injection nozzles 103a, 103e are small and the nozzle diameters of the injection nozzles 103b, 103c, 103d are large, a small amount of cooling water is injected from the injection nozzles 103a, 103e, and the injection nozzles 103b, 103c, 103d. A large amount of cooling water is jetted from. For example, in the furnace 11 (see FIG. 1), when the temperature of the exhaust gas is higher in the central part than in the wall part, a lot of cooling water is generated in the region of the inlet header 81 corresponding to the heat transfer pipe 83 arranged in the central part. Inject.

  Therefore, the temperature of the steam in the inlet header 81 becomes a distribution that becomes lower in the central portion in the longitudinal direction, and when the heat absorption amount deviation occurs in the plurality of heat transfer tubes 83 and a large amount of heat transfer tubes 83 in the central portion recovers heat, The temperature of the steam flowing out from the heat transfer pipe 83 to the outlet header 82 (see FIG. 3) is uniformly distributed in the longitudinal direction of the outlet header 82, and does not partially become a high steam temperature.

  Thus, in the superheater of 2nd Embodiment, the nozzle diameter of several injection nozzle 103a, 103b, 103c, 103d, 103e or several branch pipe 94a, 94b, 94c, 94d is used as a water injection amount adjusting device. , 94e have different tube diameters.

  Therefore, even if there is a deviation in the amount of heat collected by the plurality of heat transfer tubes 83, the outlet pipes from each heat transfer tube 83 can be adjusted in advance by adjusting the steam temperature supplied to each heat transfer tube 83 in accordance with the deviation in heat amount. The temperature of each superheated steam flowing to the header 82 can be made uniform, and the temperature difference of the superheated steam flowing out from the heat transfer tube 83 to the outlet tube header 82 can be reduced. The nozzle diameters of the injection nozzles 103a, 103b, 103c, 103d, and 103e and the pipe diameters of the branch pipes 94a, 94b, 94c, 94d, and 94e may be set in advance according to the temperature distribution of the exhaust gas in the furnace 11, There is no need to provide an adjustment device or a control device, and the structure can be simplified.

[Third Embodiment]
FIG. 8 is a schematic diagram illustrating the superheater according to the third embodiment. In addition, the same code | symbol is attached | subjected to the member which has the same function as embodiment mentioned above, and detailed description is abbreviate | omitted.

  In the third embodiment, as shown in FIG. 8, the superheater 52 includes an inlet header 81, an outlet header 82, and a plurality of heat transfer tubes 83, as in the first embodiment. A steam communication pipe 75 is connected to 81, and a steam discharge pipe 84 is connected to the outlet header 82.

  The superheat reducer 111 is provided in the inlet header 81 of the superheater 52 and cools the steam supplied from the steam communication pipe 75 to the inlet header 81 to lower the temperature. The overheat reducer 111 is configured by a water injection device 112 that can inject cooling water to the steam supplied to the inlet header 81.

  The steam communication pipe 75 is branched into a plurality of (four in this embodiment) branch communication pipes 75 a, 75 b, 75 c, 75 d at the tip, and a predetermined interval (preferably equal intervals) in the longitudinal direction of the inlet header 81. ) Position. The water injection device 112 has a plurality (four in this embodiment) of injection nozzles 92a, 92b, 92c, and 92d disposed in the branch communication pipes 75a, 75b, 75c, and 75d.

  The cooling water supply line 93 has a base end portion connected to a water supply source (not shown), and a tip end portion branched into a plurality of (four in this embodiment) branch pipes 94a, 94b, 94c, 94d. The nozzles 92a, 92b, 92c, and 92d are connected. The cooling water supply line 93 is provided with a water supply pump 95, and the branch pipes 94a, 94b, 94c, 94d are provided with flow rate adjusting valves 96a, 96b, 96c, 96d.

  Although not shown, as in the first embodiment described above, each heat transfer tube is provided with a temperature sensor, and the control device controls the flow rate adjustment valves 96a, 96b, 96c, 96d based on the measurement results of the temperature sensors. The opening can be adjusted. That is, the control device adjusts the opening degree of the flow rate adjusting valves 96a, 96b, 96c, 96d based on the measurement result of the temperature sensor, and a large amount of cooling is performed in the region of the inlet header 81 corresponding to the heat transfer tube 83 having a high temperature. Water is jetted.

  Therefore, the superheat reducer 111 lowers the temperature of the steam by injecting the cooling water to the steam in the inlet header 81 by each of the spray nozzles 92a, 92b, 92c, and 92d of the water spray device 112. At this time, the control device adjusts the opening degree of the flow rate adjusting valves 96a, 96b, 96c, 96d based on the measurement result of the temperature sensor. That is, the control device detects the temperature distribution in the plurality of heat transfer tubes 83, and from the corresponding injection nozzles 92a, 92b, 92c, 92d to the region of the inlet header 81 to which the high temperature heat transfer tubes 83 are connected. Increase the amount of cooling water injected.

  Therefore, the temperature of the steam in the inlet header 81 has a distribution that decreases in a region where a large amount of cooling water is injected, and a heat absorption amount deviation occurs in the plurality of heat transfer tubes 83 so that the heat transfer tubes 83 in this region have a large amount of heat. When recovered, the temperature of the steam flowing out from the heat transfer pipe 83 to the outlet header 82 (see FIG. 3) becomes a uniform distribution in the longitudinal direction of the outlet header 82, and the steam temperature does not partially increase. Then, the superheated steam that has moved to the outlet header 82 through the plurality of heat transfer tubes 83 is discharged to the steam discharge tube 84.

  As described above, in the superheater of the third embodiment, a plurality of branch connecting pipes 75a, 75b, 75c, and 75d that supply steam are connected at a predetermined interval in the longitudinal direction of the inlet header 81, and a plurality of injection nozzles are connected. 92a, 92b, 92c, and 92d are disposed in the branch connection pipes 75a, 75b, 75c, and 75d, respectively.

  Therefore, even if there is a deviation in the amount of heat collected by the plurality of heat transfer tubes 83, the outlet pipes from each heat transfer tube 83 can be adjusted in advance by adjusting the steam temperature supplied to each heat transfer tube 83 in accordance with the deviation in heat amount. The temperature of each superheated steam flowing to the header 82 can be made uniform, and the temperature difference of the superheated steam flowing out from the heat transfer tube 83 to the outlet tube header 82 can be reduced. Further, since the cooling water is injected into the branch connecting pipes 75a, 75b, 75c, and 75d, the temperature of the steam supplied to the heat transfer pipe 83 is accurately adjusted in order to adjust the temperature before the steam is supplied to the inlet header 81. It can be adjusted, and high-precision temperature management can be performed.

[Fourth Embodiment]
FIG. 9 is a schematic diagram illustrating the superheater according to the fourth embodiment. In addition, the same code | symbol is attached | subjected to the member which has the same function as embodiment mentioned above, and detailed description is abbreviate | omitted.

  In the fourth embodiment, as shown in FIG. 9, the superheater 52 includes an inlet header 81, an outlet header 82, and a plurality of heat transfer tubes 83. The superheat reducer 121 cools the steam supplied from the steam communication pipe 75 to the inlet header 81 and lowers the temperature. The overheat reducer 121 is configured by a water injection device 122 capable of injecting cooling water to the steam supplied to the inlet header 81.

  The water injection device 122 has a plurality (two in this embodiment) of injection nozzles 123a and 123b arranged at predetermined intervals in the longitudinal direction of the inlet header 81. The plurality of injection nozzles 123 a and 123 b are arranged in the inlet header 81, and the injection ports are arranged in the longitudinal direction of the inlet header 81. Here, the two injection nozzles 123a and 123b are arranged on the end side of the inlet header 81, and the injection ports face the center, so that each of the injection nozzles 123a and 123b corresponds to the inlet header 81. Cooling water can be jetted to the central portion side in the longitudinal direction.

  The cooling water supply line 124 is branched at its distal end into a plurality of branch pipes 125a and 125b and connected to the respective injection nozzles 123a and 123b. And the water supply pump 126 is provided in the cooling water supply line 124, and the flow regulating valves 127a and 127b are provided in the branch pipes 125a and 125b.

  The superheater 52 of this embodiment has a water injection amount adjustment device that can adjust the water injection amount in the longitudinal direction of the inlet header 81 by controlling the water injection device 122 that constitutes the overheat reducer 121. Yes. This water injection amount adjusting device includes a plurality of injection nozzles 123a and 123b, a plurality of branch pipes 125a and 125b, flow rate adjustment valves 127a and 127b, and the like.

  Accordingly, the superheat reducer 121 reduces the temperature of the steam by injecting the cooling water to the steam in the inlet header 81 by the spray nozzles 123 a and 123 b of the water spray device 122. At this time, the injection nozzles 123a and 123b inject the cooling water toward the central portion in the longitudinal direction of the inlet header 81 because the respective injection ports are directed toward the central portion. For example, in the furnace 11 (see FIG. 1), when the temperature of the exhaust gas is higher than that of the wall portion, the furnace portion 11 supplies a large amount of cooling water in the region of the inlet header 81 corresponding to the heat transfer tube 83 arranged in the center portion. Spray.

  Therefore, the temperature of the steam in the inlet header 81 becomes a distribution that becomes lower in the central portion in the longitudinal direction, and when the heat absorption amount deviation occurs in the plurality of heat transfer tubes 83 and a large amount of heat transfer tubes 83 in the central portion recovers heat, The temperature of the steam flowing out from the heat transfer pipe 83 to the outlet header 82 (see FIG. 3) is uniformly distributed in the longitudinal direction of the outlet header 82, and does not partially become a high steam temperature.

  Note that the positions, orientations, number, and the like of the injection nozzles 123a, 123b may be appropriately set according to the temperature distribution of the exhaust gas in the furnace 11.

  Thus, in the superheater of 4th Embodiment, the injection nozzles 123a and 123b which can inject a cooling water toward the longitudinal direction of the inlet header 81 are provided as a water injection amount adjusting device as a water injection device. ing.

  Therefore, even if there is a deviation in the amount of heat collected by the plurality of heat transfer tubes 83, the outlet pipes from each heat transfer tube 83 can be adjusted in advance by adjusting the steam temperature supplied to each heat transfer tube 83 in accordance with the deviation in heat amount. The temperature of each superheated steam flowing to the header 82 can be made uniform, and the temperature difference of the superheated steam flowing out from the heat transfer tube 83 to the outlet tube header 82 can be reduced. Moreover, since the injection nozzles 123a and 123b inject the cooling water toward the longitudinal direction of the inlet header 81, the cooling water can be spread over a wide range. Furthermore, the positions and orientations of the injection nozzles 123a and 123b may be set in advance according to the temperature distribution of the exhaust gas in the furnace 11, and it is not necessary to separately provide an adjustment device or a control device, and the structure can be simplified. .

  In the above-described embodiment, the two superheaters 51 and 52 are arranged in series in the flue 50, but may be one or three or more. Moreover, although the superheat reducer 66 was provided in the superheaters 51 and 52, since the reheaters 53 and 54 also superheat steam like the superheater, they have the same function as this superheater. Therefore, an overheat reducer may be provided at the inlet header of the reheater 54 on the downstream side. That is, the superheater of the present invention includes superheaters 51 and 52 and reheaters 53 and 54.

DESCRIPTION OF SYMBOLS 10 Boiler 11 Furnace 12 Combustion device 21,22,23,24,25 Combustion burner 50 Flue 51,52 Superheater 53,54 Reheater 55,56,57 Eco-saving device 61 Water supply line 62 Water supply pump 64 Heat transfer pipe 65 Steam line 66, 101, 111, 121 Superheat reducer 67 Steam turbine 71, 81 Inlet header 72, 82 Outlet header 73, 83 Heat transfer pipe 75 Steam communication pipe 75a, 75b, 75c, 75d Branch communication pipe 91, 102, 112, 122 Water injection device 92a, 92b, 92c, 92d, 92e Injection nozzle (water injection amount adjusting device)
93 Cooling water supply line 94a, 94b, 94c, 94d, 94e Branch pipe (cooling water supply pipe, water injection amount adjusting device)
95 Water supply pump 96a, 96b, 96c, 96d, 96e Flow rate adjusting valve (water injection amount adjusting device)
97a, 97b, 97c Temperature sensor 98 Control device

Claims (8)

An inlet header to which steam is supplied;
An outlet header for discharging the generated superheated steam;
A plurality of heat transfer tubes arranged in a longitudinal direction of the inlet header and the outlet header so as to connect the inlet header and the outlet header;
A water injection device capable of injecting cooling water to the steam supplied to the inlet header;
A water injection amount adjusting device capable of adjusting the water injection amount in the longitudinal direction of the inlet header by controlling the water injection device;
The superheater characterized by having.   The water injection device has a plurality of injection nozzles arranged at predetermined intervals in the longitudinal direction of the inlet header, and the water injection amount adjustment device is capable of adjusting a water injection amount by the plurality of injection nozzles. The superheater according to claim 1.   The superheater according to claim 2, wherein a plurality of injection nozzles are disposed in the inlet header.   The plurality of steam communication pipes for supplying steam are connected at a predetermined interval in the longitudinal direction of the inlet header, and the plurality of injection nozzles are respectively disposed in the steam communication pipes. Superheater.   The superheater according to any one of claims 2 to 4, wherein the water injection amount adjusting device includes a flow rate adjusting valve provided in each cooling water supply pipe to the plurality of injection nozzles. .   The said water injection amount adjustment apparatus is comprised by the pipe diameter of each cooling water supply pipe | tube to each nozzle diameter of these injection nozzles or these injection nozzles being different. The superheater as described in any one of Claims 4.   The superheater according to claim 1, wherein the water injection device has an injection nozzle capable of injecting cooling water toward a longitudinal direction of the inlet header. A furnace that is hollow and installed along the vertical direction;
A combustion device for injecting fuel into the furnace;
The superheater according to any one of claims 1 to 7, wherein the superheater is provided in a flue of the furnace and recovers heat of exhaust gas to generate superheated steam.
The boiler characterized by having.

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