Abstract:
A drain discharge equipment of a compressor having a separator for separating drain discharged from the compressor to compressed air and liquid drain, which is disposed on some part of a drain capture pipe connected between stages and/or to an outlet of the compressor to compress air with a liquid sprayed, and discharging the liquid drain separated by the separator to outside the compressor through a discharge pipe system, characterized in that the separator is provided with a device for intermittently discharging the liquid drain separated by the separator to the discharge pipe system.

Description:
CLAIM OF PRIORITY 
       [0001]    The present application claims priority from Japanese patent application serial No. 2011-016025, filed on Jan. 28, 2011 which is hereby incorporated by reference into this application. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to drain discharge equipment of a compressor and a gas turbine system and more particularly to drain discharge equipment of a compressor and a gas turbine system which are preferable for an apparatus having a separator for separating drain, which gets mixed in the compressor when a liquid is sprayed to gas fed to the compressor, to a liquid and compressed air. 
         [0004]    2. Description of Related Art 
         [0005]    A high-humidity gas use gas turbine system for spraying a liquid to gas (air) fed to a compressor for humidification, driving the gas turbine, thereby improving the efficiency is well known (refer to Patent Document 1 and Patent Document 2). 
         [0006]    However, in the high-humidity gas use gas turbine system aforementioned, when the liquid is sprayed to air, the spray liquid enters the compressor, and the spray liquid collides with the movable blades and static blades of the compressor, thus drain is generated, and the drain enters extracted air of the compressor. The extracted air of the compressor is used as seal air for a bearing for bearing the rotary shaft of the compressor and/or cooling air for the blades of the gas turbine, so that it is necessary to capture drain entering the extracted air of the compressor. 
         [0007]    As a conventional system for capturing drain entering the extracted air of the compressor, the following may be cited. 
         [0008]    The conventional embodiment (1) shown in  FIG. 4  is a conventional axial flow compressor. In this drawing, numeral  1  indicates an axial flow compressor, and the axial flow compressor  1  is driven by a compressor drive unit  17 , and both ends of the rotary shaft are born by bearings  3 . Further, to the axial flow compressor  1 , an air intake system  21  for spraying a liquid  6  to air  5  and sucking it into the compressor is connected. Furthermore, between the stages of the axial flow compressor  1 , an inter-stage drain capture pipe  7  of the compressor is connected and in the lowermost portion thereof, a separator  13 A for separating drain passing through the inter-stage drain capture pipe  7  of the compressor to compressed air and a liquid with dust mixed together is disposed. The liquid with dust mixed together which is separated by the separator  13 A is discharged outside the compressor through a discharge pipe system  11 A, and on the other hand, the compressed air separated by the separator  13 A is fed to the bearings  3  via seal air pipe systems  9  and is used as seal air for the bearings  3 . Further, to the outlet of the axial flow compressor  1 , an exit drain capture pipe  8  of the compressor is connected and in the lowermost portion thereof, a separator  13 B for separating drain passing through the exit drain capture pipe  8  of the compressor to compressed air and a liquid with dust mixed together is disposed. The liquid with dust mixed together which is separated by the separator  13 B is discharged outside the compressor through a discharge pipe system  11 B, and on the other hand, the compressed air separated by the separator  13 B is fed, for example, to equipment such as a chemical process via an equipment drive air extraction pipe system  16  and is used as equipment drive air. 
         [0009]    Next, the conventional embodiment (2) shown in  FIG. 5  is a conventional centrifugal compressor. In this drawing, numerals  20 A and  20 B indicate a centrifugal compressor, and the centrifugal compressors  20 A and  20 B are placed side by side with each other and are driven by a compressor drive unit  17 , and both ends of the rotary shaft are born by the bearings  3 . Further, the air intake pipe system  21  for spraying the liquid  6  to the air  5  and sucking it into the compressor is connected to the centrifugal compressor  20 A. Furthermore, the inter-stage drain capture pipe  7  of the compressor is connected to the centrifugal compressor  20 A and in the lowermost portion thereof, the separator  13 A for separating drain passing through the inter-stage drain capture pipe  7  of the compressor to compressed air and a liquid with dust mixed together is disposed. The liquid with dust mixed together which is separated by the separator  13 A is discharged outside the compressor through the discharge pipe system  11 A, and on the other hand, the compressed air separated by the separator  13 A is fed to the bearings  3  via the seal air pipe systems  9  and is used as seal air for the bearings  3 . Further, at the outlet of the centrifugal compressor  20 B connected to a drain capture pipe  7 ′ branching and extending from some part of the inter-stage drain capture pipe  7  of the compressor, an exit drain capture pipe  8  of the compressor is connected and in the lowermost portion thereof, the separator  13 B for separating drain passing through the exit drain capture pipe  8  of the compressor to compressed air and a liquid with dust mixed together is disposed. The liquid with dust mixed together which is separated by the separator  13 B is discharged outside the compressor through the discharge pipe system  11 B, and on the other hand, the compressed air separated by the separator  13 B is fed, for example, to equipment such as a chemical process via the equipment drive air extraction pipe system  16  and is used as equipment drive air. 
         [0010]    Furthermore, the conventional embodiment (3) shown in  FIG. 6  is a conventional gas turbine system. As shown in this drawing, the gas turbine system, except the drive source, is schematically composed of the axial flow compressor  1  similar to the conventional embodiment (1), a combustor  4  for burning compressed air  22  which is discharged to the exit drain capture pipe  8  of the compressor extending from the outlet of the axial flow compressor  1  and is branched and led from some part of the exit drain capture pipe  8  of the compressor and fuel, and a gas turbine  2  driven by combustion gas  23  burnt by the combustor  4 . The axial flow compressor  1  aforementioned is driven by the gas turbine  2  and both ends of the rotary shaft are born by the bearings  3 . 
         [0011]    Further, in the conventional embodiment (3), between the stages of the axial flow compressor  1 , two inter-stage drain capture pipes  7 A and  7 B of the compressor are connected and in the lowermost portions of the pipes, the separators  13 A and  13 B for separating drain passing through the inter-stage drain capture pipes  7 A and  7 B of the compressor to compressed air and a liquid with dust mixed together are disposed. The liquids with dust mixed together which are separated by the separators  13 A and  13 B are fed to the discharge pipe system  11 A through respective discharge pipe systems  11 A 1  and  11 A 2  and are discharged outside the compressor. On the other hand, the compressed air separated by the separator  13 A is discharged to a compressed air pipe system  24 A, is fed to one of the bearings  3  via a seal air pipe system  9 A branching from some part of the compressed air pipe system  24 A, furthermore, is fed to the other bearing  3  via a seal air pipe system  9 B branching from some part of the compressed air pipe system  24 A, and is used as seal air for the respective bearings  3 . The leading edge of the compressed air pipe system  24 A is connected to the gas turbine  2  and the compressed air discharged from the separator  13 A is led into the gas turbine  2  and is used as cooling air  10  for the blades. Further, the compressed air separated by the separator  13 B is discharged to the compressed air pipe system  24 B with the leading edge connected to the gas turbine  2  and the compressed air discharged from the separator  13 B is led into the gas turbine  2  and is used as cooling air  10  for the blades. 
         [0012]    Furthermore, in the conventional embodiment (3), in the lowermost portion of the exit drain capture pipe  8  of the compressor connected to the outlet of the axial flow compressor  1 , a separator  13 C for separating drain discharged from the axial flow compressor  1  to compressed air and a liquid with dust mixed together is disposed. The liquid with dust mixed together which is separated by the separator  13 C is fed to the discharge pipe system  11 A through a discharge pipe system  11 A 3  and is discharged outside the compressor, and on the other hand, the compressed air separated by the separator  13 C is led into the gas turbine  2  and is used as cooling air  10  for the blades. 
         [0013]    Document of Prior Art 
         [0014]    {Patent Document 1} Japanese Patent Laid-open No. 2008-196399 
         [0015]    {Patent Document 2} Japanese Patent Laid-open No. 2006-57607 
       SUMMARY OF INVENTION 
       [0016]    The separators  13 A and  13 B in the conventional embodiments (1) and (2) are generally structured so as to always discharge about 1/10 of entrance air of the separators  13 A and  13 B (holes for drawing out drain of about 1/10 of entrance air of the separators  13 A and  13 B are formed in the separators  13 A and  13 B and pipes are connected to them), and when a small amount of the liquid  6  gets mixed in the axial flow compressor  1  or the centrifugal compressors  20 A and  20 B, liquid drain is discharged out through the discharge pipe system  11  together with compressed air, so that seal air fed to the bearings  3  from the seal air pipe systems  9  or equipment drive air fed from the equipment drive air extraction pipe system  16  can keep the purity. 
         [0017]    However, when the liquid  6  of a quantity exceeding the capacity of the separators  13 A and  13 B gets mixed in the axial flow compressor  1  or the centrifugal compressors  20 A and  20 B, a liquid (steam included) which cannot be separated and removed by the separators  13 A and  13 B flows into seal air for sealing the bearings  3  and equipment drive air, and moisture gets mixed in the lubricating oil of the bearings  3 , and moisture gets mixed in the equipment drive air, thus there is a fear that the stable operation of the system may be inhibited. 
         [0018]    Further, when a small amount of the liquid  6  gets mixed in the axial flow compressor  1  or the centrifugal compressors  20 A and  20 B and the purity of seal air for the bearings  3  and equipment drive air can be kept by the separators  13 A and  13 B or even under the condition that the liquid  6  does not get mixed in the axial flow compressor  1  or the centrifugal compressors  20 A and  20 B, in the separators  13 A and  13 B, a part of compressed air leaks outside the compressor, so the efficiency of the compressor reduces. 
         [0019]    Furthermore, the pressure of the liquid discharged from the axial flow compressor  1  or the centrifugal compressors  20 A and  20 B reduces because of the structure that about 1/10 of entrance air of the separators  13 A and  13 B is always discharged, that is, the structure that it passes through a minute orifice. Therefore, when capturing the liquid discharged from the axial flow compressor  1  or the centrifugal compressors  20 A and  20 B, it is necessary to put it together at one place and transfer it by a transfer pump separately prepared and arranged and in correspondence to the pump power equipped, the efficiency of the system using the axial flow compressor  1  or the centrifugal compressors  20 A and  20 B reduces. 
         [0020]    Next, the separators  13 A,  13 B, and  13 C in the conventional embodiment (3) are generally structured so as to always discharge about 1/10 of entrance air of the separators  13 A,  13 B, and  13 C (holes for drawing out drain of about 1/10 of entrance air of the separators  13 A,  13 B, and  13 C are formed in the separators  13 A,  13 B, and  13 C and pipes are connected to them), and when a small amount of the liquid  6  gets mixed in the axial flow compressor  1 , liquid drain is discharged out through the discharge pipe system  11  together with compressed air, thus seal air fed to the bearings  3  from the seal air pipe systems  9 A and  9 B or the cooling air  10  for the blades of the gas turbine  2  can keep the purity. 
         [0021]    However, when the liquid  6  of a quantity exceeding the capacity of the separators  13 A,  13 B, and  13 C gets mixed in the axial flow compressor  1 , a liquid (steam included) which cannot be separated and removed by the separators  13 A,  13 B, and  13 C flows into seal air for sealing the bearings  3  and the cooling air  10  for the blades of the gas turbine  2 , and if moisture gets mixed in the lubricating oil of the bearings  3  and the cooling air  10  with moisture mixed in flows to the blades of the gas turbine  2 , destruction of the blades due to a temperature difference is a concern, thus there is a fear that the stable operation of the system may be inhibited. 
         [0022]    Further, when a small amount of the liquid  6  gets mixed in the axial flow compressor  1  and the purity of seal air for the bearings  3  and the cooling air  10  for the blades of the gas turbine  2  can be kept by the separators  13 A,  13 B, and  13 C or even under the condition that the liquid  6  does not get mixed in the axial flow compressor  1 , in the separators  13 A,  13 B, and  13 C, a part of compressed air leaks outside the compressor, so the efficiency of the compressor reduces. 
         [0023]    Furthermore, the pressure of the liquid discharged from the axial flow compressor  1  reduces because of the structure that about 1/10 of entrance air of the separators  13 A,  13 B, and  13 C is always discharged, that is, the structure that it passes through a minute orifice. Therefore, when capturing the liquid discharged from the axial flow compressor  1 , it is necessary to put it together at one place and transfer it by a transfer pump separately prepared and arranged and in correspondence to the pump power equipped, the efficiency of the system using the axial flow compressor  1  reduces. 
         [0024]    The present invention was developed with the foregoing viewpoint and an object of the present invention is to provide a drain discharge equipment of a compressor and a gas turbine system, even if the compressor or gas turbine is supposed to cause mixing-in of a liquid, capable of realizing a stable operation and high efficiency. 
         [0025]    A drain discharge equipment of the compressor of the present invention, to accomplish the above object, having a separator for separating drain discharged from the compressor to compressed air and liquid drain, which is disposed on some part of a drain capture pipe connected between stages and/or to an outlet of the compressor to compress air with a liquid sprayed, and discharging the liquid drain separated by the separator to outside the compressor through a discharge pipe system, characterized in that the separator is provided with a device for intermittently discharging the liquid drain separated by the separator to the discharge pipe system. 
         [0026]    Further, a gas turbine system of the present invention, to accomplish the above object, having a compressor for compressing air with a liquid sprayed, a combustor disposed on some part of a pipe branching from some part of a drain capture pipe connected to an outlet of the compressor for burning the compressed air from the compressor and fuel, and a turbine driven by combustion gas burned by the combustor, a separator for separating drain discharged from the compressor to compressed air and liquid drain, which is disposed on some part of the drain capture pipe connected between stages and/or to an outlet of the compressor, wherein the liquid drain separated by the separator is discharged to outside the compressor through the discharge pipe system and the compressed air separated by the separator is introduced to blades of the turbine as cooling air, characterized in that the separator is provided with a device for intermittently discharging the liquid drain separated by the separator to the discharge pipe system. 
         [0027]    According to the present invention, drain discharge equipment of a compressor and a gas turbine system, even if the compressor or gas turbine is supposed to cause mixing-in of a liquid, capable of realizing a stable operation and high efficiency can be obtained. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0028]      FIG. 1  is a system diagram showing a first embodiment of the drain discharge equipment of the compressor of the present invention which is applied to the axial flow compressor, 
           [0029]      FIG. 2  is a system diagram showing a second embodiment of the drain discharge equipment of the compressor of the present invention which is applied to the centrifugal compressor, 
           [0030]      FIG. 3  is a system diagram showing a third embodiment of the gas turbine system of the present invention, 
           [0031]      FIG. 4  is a system diagram showing a conventional drain discharge equipment of the compressor which is applied to the axial flow compressor, 
           [0032]      FIG. 5  is a system diagram showing another conventional drain discharge equipment of the compressor which is applied to the centrifugal compressor, and 
           [0033]      FIG. 6  is a system diagram showing a conventional gas turbine system. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0034]    Hereinafter, the present invention will be explained in detail on the basis of the embodiments drawn. Further, for the similar constitution to the conventional embodiment, the detailed explanation is omitted and with respect to the numerals, for the similar articles to the conventional, the same numerals are used. 
       Embodiment 1 
       [0035]      FIG. 1  is a drawing showing a first embodiment of the present invention which is applied to the axial flow compressor. 
         [0036]    The embodiment 1 shown in the  FIG. 1  has a constitution almost similar to that of the conventional embodiment (1) shown in  FIG. 4 . In the embodiment 1, the separator  13 A is installed in the lowermost portion of the inter-stage drain capture pipe  7  of the compressor connected between the stages of the axial flow compressor  1  for separating drain passing through the inter-stage drain capture pipe  7  of the compressor to compressed air and a liquid with dust mixed together. The separator  13 B is installed in the lowermost portion of the exit drain capture pipe  8  of the compressor connected to the outlet of the axial flow compressor  1  for separating drain passing through the exit drain capture pipe  8  of the compressor to compressed air and a liquid with dust mixed together. And the level sensors  14 A and  14 B for detecting the liquid quantities flowing into the separators  13 A and  13 B are disposed and so as to prevent an operation exceeding the capacity of the separators  13 A and  13 B, on some part of the discharge pipe systems  11 A and  11 B, on the liquid drain pipes (liquid transfer pipes), drain discharge valves  15 A and  15 B for operating working together with the level sensors  14 A and  14 B are installed. 
         [0037]    According to such a constitution of the embodiment 1, even if the liquid  6  of a quantity exceeding the capacity of the separators  13 A and  13 B gets mixed in the axial flow compressor  1 , the quantity of the liquid  6  can be detected by the level sensors  14 A and  14 B, and if the detection quantity by the level sensors  14 A and  14 B is a quantity exceeding the capacity of the separators  13 A and  13 B (when it exceeds a predetermined value), an intermittent operation for opening the drain discharge valves  15 A and  15 B operated working together with the level sensors  14 A and  14 B are performed, thus the drain can be discharged to the discharge pipe systems  11 A and  11 B and the liquid quantity inside the separators  13 A and  13 B can be kept appropriately. 
         [0038]    Therefore, the drain can be separated appropriately to compressed air and a liquid with dust mixed in by the separators  13 A and  13 B, and a liquid which cannot be separated by the separators  13 A and  13 B does not flow into the seal air for sealing the bearings  3  and the equipment drive air, and a fear of inhibiting the stable operation of the system due to moisture getting mixed in the lubricating oil of the bearings  3  and moisture getting mixed in the equipment drive air is eliminated, and a stable operation of the axial flow compressor  1  can be performed. 
         [0039]    Further, in the conventional embodiment (1), due to the stationary leak of compressed air from the separators  13 A and  13 B, a reduction effect of the axial flow compressor  1  is caused. Therefore, in the embodiment 1, the level sensors  14 A and  14 B are separately disposed on the upper portion and lower portion of the separators  13 A and  13 B for sensing the quantity of the liquid in the separators  13 A and  13 B and controlling the drain discharge valves  15 A and  15 B are controlled so as to discharge only the liquid in the separators  13 A and  13 B. 
         [0040]    By use of this system, the leak of compressed air from the separators  13 A and  13 B can be brought close to zero and the efficiency of the axial flow compressor  1  can be improved. 
         [0041]    Furthermore, in the conventional embodiment (1), a liquid discharged from the axial flow compressor  1  becomes low in pressure, so that a transfer pump separately installed is necessary, though in the embodiment 1, the drain discharge valves  15 A and  15 B disposed on some part of the discharge pipe systems  11 A and  11 B between the stages and at the outlet of the axial flow compressor  1  are fully born, that is, valve holes with the same diameter as that of the pipe are formed, and switching drain is discharged into the valve holes, thus a state that the inner pressure of the compressor is directly applied to the liquid is created. 
         [0042]    By doing this, the liquid in the separators  13 A and  13 B can be subjected to pressure transfer by the upstream pressure of each of the drain discharge valves  15 A and  15 B, so that the transfer pump separately installed is not necessary and the efficiency of the axial flow compressor  1  can be improved. 
       Embodiment 2 
       [0043]      FIG. 2  is a drawing showing a second embodiment of the present invention which is applied to the centrifugal compressor. 
         [0044]    The embodiment 2 shown in  FIG. 2  has a constitution almost similar to that of the conventional embodiment (2) shown in  FIG. 5 . In the embodiment 2, the separator  13 A is installed in the lowermost portion of the inter-stage drain capture pipe  7  of the compressor connected between the stages of the axial flow compressor  1  for separating drain passing through the inter-stage drain capture pipe  7  of the compressor to compressed air and a liquid with dust mixed together. The separator  13 B is installed in the lowermost portion of the exit drain capture pipe  8  of the compressor connected to the outlet of the axial flow compressor  1  for separating drain passing through the exit drain capture pipe  8  of the compressor to compressed air and a liquid with dust mixed together. And the level sensors  14 A and  14 B for detecting the liquid quantities flowing into the separators  13 A and  13 B are disposed and so as to prevent an operation exceeding the capacity of the separators  13 A and  13 B, on some part of the discharge pipe systems  11 A and  11 B, on the liquid drain pipes (liquid transfer pipes), drain discharge valves  15 A and  15 B for operating working together with the level sensors  14 A and  14 B are installed. 
         [0045]    By use of such a constitution of the embodiment 2, the operation effect similar to that of the embodiment 1 aforementioned can be obtained and the stable operation of the centrifugal compressors  20 A and  20 B and the efficiency improvement can be realized. 
       Embodiment 3  
       [0046]      FIG. 3  is a drawing showing a third embodiment of the present invention which is applied to the gas turbine system. 
         [0047]    The embodiment 3 shown in  FIG. 3  has a constitution almost similar to that of the conventional embodiment (3) shown in  FIG. 6 . In the embodiment 3, in the separators  13 A and  13 B installed in the lowermost portions of the two inter-stage drain capture pipes  7 A and  7 B of the compressor connected between the stages of the axial flow compressor  1  for separating drain passing through the inter-stage drain capture pipes  7 A and  7 B of the compressor to compressed air and a liquid with dust mixed together. the separator  13 C is installed in the lowermost portion of the exit drain capture pipe  8  of the compressor connected to the outlet of the axial flow compressor  1  for separating drain discharged from the axial flow compressor  1  to compressed air and a liquid with dust mixed together. And the level sensors  14 A and  14 B for detecting the liquid quantities flowing into the separators  13 A,  13 B and  13 C are disposed and so as to prevent an operation exceeding the capacity of the separators  13 A,  13 B, and  13 C, on some part of the discharge pipe systems  11 A 1 ,  11 A 2 , and  11 A 3 , on the liquid drain pipes (liquid transfer pipes), the drain discharge valves  15 A,  15 B, and  15 C for operating working together with the level sensors  14 A and  14 B are installed. 
         [0048]    According to such a constitution of the embodiment 3, even if the liquid  6  of a quantity exceeding the capacity of the separators  13 A,  13 B, and  13 C gets mixed in the axial flow compressor  1 , the quantity of the liquid  6  can be detected by the level sensors  14 A and  14 B, and if the detection quantity by the level sensors  14 A and  14 B is a quantity exceeding the capacity of the separators  13 A,  13 B, and  13 C (when it exceeds a predetermined value), an intermittent operation for opening the drain discharge valves  15 A and  15 B operated working together with the level sensors  14 A and  14 B are performed, thus the drain can be discharged to the discharge pipe system  11 A and the liquid quantity inside the separators  13 A and  13 B can be kept appropriately. 
         [0049]    Therefore, the drain can be separated appropriately to compressed air and a liquid with dust mixed in by the separators  13 A,  13 B, and  13 C, and a liquid which cannot be separated by the separators  13 A,  13 B, and  13 C does not flow into the seal air for sealing the bearings  3  and the cooling air  10  for the blades of the gas turbine  2 , and a fear of destruction of the blades due to a temperature difference caused by moisture getting mixed in the lubricating oil of the bearings  3  and the cooling air  10  with moisture mixed in flows to the blades of the gas turbine  2  is eliminated, and a fear of inhibiting the stable operation of the system is eliminated, and a stable operation of the gas turbine system can be performed. Further, the other effects are similar to those of the embodiments 1 and 2. 
         [0050]    Further, in each embodiment aforementioned, the level sensors separately disposed at two locations on the upper portion and lower portion of the separator  13 A,  13 B, or  13 C are explained. However, a sensor for detecting the uppermost position of the liquid level in the separator  13 A,  13 B, or  13 C and a sensor for detecting the lowered position of the liquid level are necessary at its minimum limit, though the number of sensors is not limited particularly. 
         [0051]    Further, level sensors having the function of a drain discharge valve may be used. 
         [0052]    Further, in each embodiment aforementioned, the embodiment using the level sensors is explained, though if the liquid level of the separator is detected using a float in place of the level sensors and the drain discharge valve is automatically opened or closed, the similar effects can be obtained. 
         [0053]    Further, the present invention can be applied to water and deionized water and if the level sensors are changed (an electrostatic capacity sensor, an optical sensor, and others are available and they are changed depending on use), the present invention can be applied to a slurry (a mixture of a liquid and solids) or a liquid containing solid particles as the liquid drain. 
         [0054]    Furthermore, the present invention can be applied to a gas compression system using the aforementioned axial flow compressor or centrifugal compressor.