Abstract: In an apparatus of controlling an exhaust gas in an oxyfuel combustion boiler having the boiler 4 provided with burners 6 and a two-stage combustion port 7, a primary recirculation line 12 through which pulverized coal obtained by a mill 3 is fed to the burners 6 of the boiler 4 by the primary recirculating exhaust gas, a secondary recirculation line 14 through which another portion of the exhaust gas in recirculation is fed to a wind box 5 of the boiler 4, an oxygen producer 23, a direct supply line 25 through which a portion of oxygen produced by the oxygen producer 23 is directly fed to the burner 6 and a secondary oxygen mixing line 24 through which another portion of oxygen produced by the oxygen producer 23 is fed to the secondary recirculation line 14, the apparatus comprises an oxygen supply line 26 through which oxygen is fed to the two-stage combustion port of the boiler 4 and a flow rate regulator 20, 27 in the oxygen supply line for adjusting oxygen density.

Abstract: Provided are a method and an apparatus of controlling a flow rate of a primary recirculating exhaust gas in an oxyfuel combustion boiler, capable of realizing a stable combustion by a burner in oxyfuel combustion. Weight ratio of flow rate of primary recirculating exhaust gas [ton/h] to amount of pulverized coal from a mill [ton/h] is defined as G/C, and the flow rate of primary recirculating exhaust gas is controlled so that the G/C falls within a given range.

Abstract: In order to provide a pulverized coal burner for an oxyfuel combustion boiler which attains uniform combustion from a pulverized coal burner and which constrains a temperature rise of an oxygen injection nozzle, burner inner and outer cylinders are arranged to penetrate a wind box 2 and come close to a throat portion 3. A pulverized coal feed passage 9 is provided between the burner inner and outer cylinders 4 and 5. A plurality of oxygen injection means 11 are arranged outwardly of the burner outer cylinder 4 so as to directly feed oxygen ahead of the burner outer cylinder 4.

Abstract: Provided are a method and an apparatus of controlling exhaust gas in an oxyfuel combustion boiler which can attain stable combustion of the boiler while an amount of unburned combustibles and a NOx density in exhaust gas are maintained in their allowable ranges. A rate of supply of directly supplied oxygen to burners 6 to a total amount of oxygen produced by an air separation unit 18 is regulated in an operating range where the NOx density in the exhaust gas is below a NOx limit value and the amount of unburned combustibles in the exhaust gas is blow an unburned combustible limit value to thereby attain stable combustion of the oxyfuel combustion boiler.

Abstract: A method and an apparatus of controlling combustion in an oxyfuel combustion boiler are provided which ensure a sufficient furnace heat absorption through prevention of lowering of flame temperature, enabling oxyfuel combustion operations to be performed in a stable manner. A boiler-brought-in oxygen density which is an oxygen density for a total amount of gases introduced into a coal burning boiler is calculated and a flow rate of total recirculating gases is controlled such that the boiler-brought-in oxygen density falls within a predetermined range.

Abstract: Provided are a method and an apparatus of controlling an oxygen supply in an oxyfuel combustion boiler capable of attaining stable oxyfuel combustion even when properties of coal are changed. A boiler-brought-in oxygen density is obtained when coal with a fuel ratio measured by fuel measuring means 39 is burned stably with oxygen in a boiler 4 so that a relationship between the fuel ratio and/or carbon content of the coal and the boiler-brought-in oxygen density is obtained and inputted in advance into the controller. When the coal is changed to the new kind of coal, a total amount of gases recirculated is regulated such that a boiler-brought-in oxygen density becomes accordance with a fuel ratio and/or a carbon content which is measured in advance for the new kind of coal.

Abstract: Provided are fuel feed means 3, an air separation unit 6 air feed means 7, a combustion furnace 11 with a burner 9 for combustion, an exhaust gas line 14 for leading an exhaust gas from the combustion furnace 11 to outside of the combustion furnace 11, exhaust gas treatment means 20a and 20b included in the exhaust gas line 14, and a recirculation line 15 for circulating a portion of the exhaust gas at least exhaust gas treatment means 20a and 20b for recirculation of a portion of the exhaust gas at least dust-removed by the exhaust gas treatment means 20a and 20b to the burner. Further provided are exhaust gas capture means 18 for taking out carbon dioxide gas from a remaining non-recirculating exhaust gas, and carbon dioxide gas feed means 33, 40 and 46 for introducing carbon dioxide gas to equipments 10, 20a and 20b of the oxyfuel combustion boiler facility.

Abstract: A circulating fluidized bed boiler has reduced corrosion in the exchanging tube in an external heat exchanger. The circulating fluidized bed boiler has a furnace which combusts a fuel which is fluidized together with a bed material, a cyclone dust collector into which an flue gas which is generated by the combustion in the furnace is introduced and which catches particles in the flue gas, a separation loop, in a seal box, which separates corrosive components from the particles so as not to introduce the corrosive components to the external heat exchanger which is arranged downstream of the seal box.

Abstract: In a pneumatic booster, a front shell and a rear shell are connected by means of a rod. A stud bolt on one end of the rod extends through the front shell to the outside, and a support plate fitted around the stud bolt is engaged with the rod and abutted against an inner surface of the front shell. A seal member is provided in an annular groove formed in the support plate. A projection is formed in the support plate. When the support plate is reversely mounted on the stud bolt, the projection is abutted against the front shell, and the seal member is unable to provide a seal between the stud bolt and the front shell. In a leak inspection, air is flowed into a constant-pressure chamber through a cut portion formed in a distal end of the projection, to thereby detect reverse mounting of the support plate.

Abstract: An elastic member is interposed between a reaction disk and a plunger. By moving the plunger to open a poppet seal such that atmospheric air is introduced into the variable pressure chambers, a pressure differential is created between the variable pressure chambers and constant pressure chambers (negative pressure). As a result, servo power is applied to an output rod, and a resulting reaction force is partly transmitted back to an input rod through the reaction disk. During a rapid braking operation, a piston is caused to retract by a pin, thus pushing the elastic member into an outer peripheral groove formed on the piston so that the elastic member is axially compressed. As a result, the movement amount of the plunger can be increased without receiving a reaction force, enabling the rapid development of servo power.

Abstract: In a pneumatic booster, a front shell and a rear shell are connected by means of a rod. A stud bolt on one end of the rod extends through the front shell to the outside, and a support plate fitted around the stud bolt is engaged with the rod and abutted against an inner surface of the front shell. A seal member is provided in an annular groove formed in the support plate. A projection is formed in the support plate. When the support plate is reversely mounted on the stud bolt, the projection is abutted against the front shell, and the seal member is unable to provide a seal between the stud bolt and the front shell. In a leak inspection, air is flowed into a constant-pressure chamber through a cut portion formed in a distal end of the projection, to thereby detect reverse mounting of the support plate.

Abstract: A valve body 2 is connected to a power piston, which divides a housing into a constant pressure chamber (negative pressure) and a variable pressure chamber. In the valve body 2, there is provided a brake assisting mechanism 10 between a reaction disk 3 and a plunger 9. A poppet seal 12 is opened by movement of the plunger 9, to thereby introduce atmospheric air into the variable pressure chamber and generate a thrust force in the power piston. During rapid braking, a plunger rod 23 advances relative to a sleeve 21, and balls 30 shift outward and the plunger rod 23 directly abuts against a reaction rod 22, resulting in contraction of the brake assisting mechanism 10. Therefore, the amount of movement of the plunger 9 can be increased without being affected by a reaction force from the reaction disk 3, thus enabling rapid development of servo power.

Abstract: An elastic member is interposed between a reaction disk and a plunger. By moving the plunger to open a poppet seal such that atmospheric air is introduced into the variable pressure chambers, a pressure differential is created between the variable pressure chambers and constant pressure chambers (negative pressure). As a result, servo power is applied to an output rod, and a resulting reaction force is partly transmitted back to an input rod through the reaction disk. During a rapid braking operation, a piston is caused to retract by a pin, thus pushing the elastic member into an outer peripheral groove formed on the piston so that the elastic member is axially compressed. As a result, the movement amount of the plunger can be increased without receiving a reaction force, enabling the rapid development of servo power.

Abstract: A circulating fluidized bed boiler has reduced corrosion in the exchanging tube in an external heat exchanger. The circulating fluidized bed boiler has a furnace which combusts a fuel which is fluidized together with a bed material, a cyclone dust collector into which an flue gas which is generated by the combustion in the furnace is introduced and which catches particles in the flue gas, a separation loop, in a seal box, which separates corrosive components from the particles so as not to introduce the corrosive components to the external heat exchanger which is arranged downstream of the seal box.

Abstract: A valve body 2 is connected to a power piston, which divides a housing into a constant pressure chamber (negative pressure) and a variable pressure chamber. In the valve body 2, there is provided a brake assisting mechanism 10 between a reaction disk 3 and a plunger 9. A poppet seal 12 is opened by movement of the plunger 9, to thereby introduce atmospheric air into the variable pressure chamber and generate a thrust force in the power piston. During rapid braking, a plunger rod 23 advances relative to a sleeve 21, and balls 30 shift outward and the plunger rod 23 directly abuts against a reaction rod 22, resulting in contraction of the brake assisting mechanism 10. Therefore, the amount of movement of the plunger 9 can be increased without being affected by a reaction force from the reaction disk 3, thus enabling rapid development of servo power.

Abstract: A tandem pneumatic booster includes a front shell having a relatively long cylindrical portion and a rear shell having a relatively short cylindrical portion. The cylindrical portions of the front and rear shells are joined together to form a shell body. An opening edge of a cylindrical portion of a center shell is disposed in the joint between the front and rear shells, together with an outer peripheral bead of a diaphragm of a rear power piston. The cylindrical portion of each of the front, rear and center shells has a frusto-conical shape gradually increasing in diameter toward the opening edge thereof. Thus, when front shells, rear shells and center shells are stacked on one another, respectively, as constituent parts before assembly, the depth of fitting between each pair of adjacent shell elements is increased sufficiently to stably maintain the stacked conditions of the shell elements.

Abstract: A circulating fluidized bed boiler has reduced corrosion in the exchanging tube in an external heat exchanger. The circulating fluidized bed boiler has a furnace which combusts a fuel which is fluidized together with a bed material, a cyclone dust collector into which an flue gas which is generated by the combustion in the furnace is introduced and which catches particles in the flue gas, a separation loop, in a seal box, which separates corrosive components from the particles so as not to introduce the corrosive components to the external heat exchanger which is arranged downstream of the seal box.

Abstract: A tandem pneumatic booster includes a front shell having a relatively long cylindrical portion and a rear shell having a relatively short cylindrical portion. The cylindrical portions of the front and rear shells are joined together to form a shell body. An opening edge of a cylindrical portion of a center shell is disposed in the joint between the front and rear shells, together with an outer peripheral bead of a diaphragm of a rear power piston. The cylindrical portion of each of the front, rear and center shells has a frusto-conical shape gradually increasing in diameter toward the opening edge thereof. Thus, when front shells, rear shells and center shells are stacked on one another, respectively, as constituent parts before assembly, the depth of fitting between each pair of adjacent shell elements is increased sufficiently to maintain the stacked conditions of the shell elements stably.

Abstract: A tandem pneumatic booster having a shell body, the inside of which is divided into two, front and rear, chambers by a center shell. Each chamber includes a negative pressure chamber and a working pressure chamber. A valve body is slidably fitted in the shell body and the center shell with seal members therebetween. The valve body is provided with an air passage for communication between the front and rear working pressure chambers. A valve mechanism is actuated in association with an input shaft to introduce atmospheric air into the front and rear working pressure chambers through the air passage so as to apply thrust to front and rear power pistons. The diaphragm of the front power piston has a bead on an inner periphery thereof. The valve body has a groove on an outer periphery thereof. A portion of the air passage which leads to the front working pressure chamber has a main passage portion extending axially in the valve body, and a bypass extending radially outward from the main passage portion.

Abstract: A method for manufacturing a thermionic cathode is provided which comprises cutting a bar from a multi-layer structure having a first layer of thermoelectron emissive compound and a third layer of metal of high melting point, a second layer of reaction barrier being interposed between said first and third layers, the bar being cut in a direction substantially perpendicular to that of the layers, sharpening the end of the first layer of the bar and then providing current terminals with the third layer of the bar. According to the method of the invention, a thermionic cathode capable of emitting stable electron beams of high intensity for a long period of time can be manufactured.