JP4619643B2 - Steam desuperheater - Google Patents

Description

  The present invention relates to a steam temperature reducing device provided to generate steam having a pressure-temperature condition defined by the requirements of a plant in a general plant or a business plant that uses steam as a heat source.

  In a plant installed in a factory or the like, steam may be used as a heat source required in the manufacturing process. It uses the latent heat released when the steam condenses. By maintaining the steam pressure at the specified pressure, the temperature of heat use at that time is extremely stable. It is used in.

  A boiler or the like is used as a steam generation source. At that time, as a method for improving the efficiency of the boiler, the high pressure and high temperature specifications are usually set. For example, in a plant, steam generated by a boiler is used to drive an industrial steam turbine to rotate a generator to obtain electricity, and control the extraction of these steam turbines as factory steam to reduce the pressure. Taking out the reduced temperature steam. However, since the depressurization / temperature reduction effect by the turbine is determined by the turbine load at that time, in general, the bleed pressure is controlled to be a predetermined value in the turbine control device. For this reason, the extraction temperature varies depending on the turbine load, and a temperature reducer is used to control the extraction temperature to a steam temperature that meets the requirements on the steam use side.

  FIG. 11 shows an example of the configuration of a conventional temperature reducer. That is, the spray nozzle 52 is provided in the vicinity of the inlet of the temperature reducing pipe 51 so that spraying can be performed in the pipe. The spray nozzle 52 is connected to an outside pipe 53 of the temperature reducing pipe 51, and a cooling water flow rate adjustment valve 54 is provided in the middle of the outside pipe 53. Further, a temperature detector 55 is disposed at the outlet of the temperature reducing pipe 51, and a temperature reducing device control device 56 that controls the cooling water flow rate adjusting valve 54 according to the detection result of the temperature detector 55 is provided.

In such a conventional steam temperature reducing device, the superheated steam 60 is sent to one end of the temperature reducing pipe 51 from a boiler or a turbine. The superheated steam 60 is sent at a pressure that takes into account the pressure loss required by the steam temperature reducing device and piping in addition to the pressure required by the user. The cooling water 58 sprayed from the spray nozzle 52 and used to reduce the temperature of the superheated steam 60 is sprayed to this steam pressure and injected into the pressure loss and steam flow due to each component of the steam temperature reducing device. It is supplied from a system having a pressure that takes into account the minimum pressure loss required by the nozzle 52.

Supplied cooling water 58 is adjusted so that at the cooling water flow rate adjustment valve 54 becomes a predetermined amount of cooling water is injected into the nebulized down temperature pipe 51 at the spray nozzle 52. By injecting the cooling water 58, the superheated steam 60 and the mist-like cooling water 58 exchange heat while flowing through the temperature reducing pipe 51, and the water droplets of the cooling water 58 start to rise in temperature.

  When the temperature of the water droplet reaches the saturation temperature inside the temperature reducing tube 51, the water droplet starts to evaporate, and the superheated steam 60 and the saturated steam are mixed. Thereafter, the vapor temperature is made uniform by mixing these vapors, and finally reaches the outlet of the temperature reducing pipe 51. A temperature detector 55 is installed at the outlet of the temperature reducing pipe 51, and the temperature of the steam after the temperature reduction is measured and sent to the temperature reducing device controller 56. The temperature reducer control device 56 adjusts the amount of cooling water to be injected from the difference between this signal and the steam temperature required by the user, and the cooling water flow rate adjustment valve as indicated by the alternate long and short dash line so as to obtain a predetermined temperature. 54 is operated.

  Factors that influence the performance of the temperature reducer include (a) superheated degree of superheated steam 60, (b) temperature of cooling water 58, (c) particle size of mist after spraying, (d) steam flow after mixing. (E) the length of the temperature reducing pipe 51, (f) the length of the straight pipe of the temperature reducing pipe 51, and (g) the length to the temperature detector 55.

Of these, (a), (b) and (c) are determined by given operating conditions and plant equipment conditions. In addition, (d), (e), (f), and (g) have restrictions such as the layout of equipment, and for (c), the usable cooling water flow rate range is determined by the shape of the spray nozzle 52 itself. There are various restrictions. (For example, see Patent Document 1)
In addition, a steam temperature reducing device is provided with an ejector disposed in a steam pipe having an inlet and an outlet, a swirl blade is mounted therein, and a cooling fluid injection part is provided. The ejector is a nozzle as a constricting part that restricts the flow path. A structure formed by a suction chamber and a diffuser portion is also disclosed. (For example, see Patent Document 2)
JP 2003-207102 (paragraph numbers 0002 to 0008) JP 2000-146110 (paragraph numbers 0009 to 0011)

Steam down raising device shown in Patent Document 1 mentioned above are those dispersed mixture of cooling fluid through the spray nozzle into a high pressure at and high temperature superheated steam flowing through the pipe body to decrease the temperature of the temperature of the superheated steam However, in this case, it is conceivable that high-temperature superheated steam and the cooling fluid in the course of vaporization contact with each other on the wall surface of the tube, causing thermal stress to break the tube.

  In addition, a certain amount of time (tube length) is required until the cooling fluid is completely vaporized and uniform and stable temperature-reduced steam is obtained, so that the facility is expected to be complicated and long.

Further, the steam down-raising device shown in Patent Document 2 described above, although supplying cooling water from the perpendicular direction in the suction chamber relative to the direction of flow of the superheated steam, the cooling water superheated steam and is sufficiently homogeneous It is difficult to mix with

  From these situations, various problems occur in the prior art, and the assumed temperature reduction effect cannot be exhibited.

  The present invention has been made based on these circumstances, and promotes uniform dispersive mixing of the high-temperature and high-pressure superheated steam and the cooling fluid mixed therewith, so that the temperature of the superheated steam can be made uniform. An object of the present invention is to provide a steam temperature reducing device capable of reducing the temperature.

According to the present invention, the superheated steam pipe for allowing the superheated steam, which is the high-pressure stage bleed gas of the turbine, to flow into the inside of the temperature reducing pipe is communicated with one side end so as to form a conduit integrally with the temperature reducing pipe. A steam temperature reducing device in which a steam pipe for allowing the steam discharged from the temperature reducing pipe to flow into a side end is communicated with the temperature reducing pipe so as to form a conduit integrally therewith;
The temperature reducing pipe has a nozzle shape in which a constricted portion having a smaller inner diameter at the center than the both side ends is formed, and in the constricted portion, cooling steam that is a low-pressure stage extraction of the turbine is placed in the temperature reducing pipe. It provided cooling steam introduction pipe for introducing the said inner diameter of the communication portion that is connected to the steam pipe before Symbol decreased temperature tube is formed as a large consisting inner diameter of the constricted portion, the vapor of the reduced temperature tube The internal diameter of the communication part connected to the pipe is formed to be larger than the internal diameter of the communication part connected to the superheated steam pipe of the temperature reducing pipe, and the cooling steam supplied to the cooling steam introduction pipe is : The steam pipe is drawn into the temperature reducing pipe by the ejector effect of the nozzle action of the temperature reducing pipe, which is set at a lower pressure and lower temperature than the superheated steam, and the high temperature and high temperature superheated steam that has passed through the superheated steam pipe flows. Turkey to flows been blown to It is steam down raising device according to claim.

According to the invention, the steam pipe is provided with a temperature detector, the output of the temperature detector is connected to a temperature controller, and the output of the temperature controller is provided in the cooling steam introduction pipe. The steam temperature reducing device is characterized in that the opening degree of the temperature control valve is adjusted.

According to the invention, said superheated steam pipe is introduced high-pressure stage bleed air from the turbine, said cooling steam pipe is steam down raising device according to claim Rukoto low pressure stage bleed air is introduced from the turbine .

According to the present invention, the cooling steam is steam down raising device being characterized in that by using the steam generated in the heat exchanger connected to the cold 却蒸gas inlet tube.

According to the present invention, the cooling steam, and characterized in that using steam flushing under reduced pressure by the cold 却蒸 via drain heat exchanger is connected to the gas inlet pipe temperature regulating valve It is a steam temperature reducing device.

  According to the invention, there is provided a steam temperature reducing device characterized in that a plurality of the cooling steam introducing pipes provided in the constricted portion of the temperature reducing pipe are provided.

  According to the present invention, there is provided a steam temperature reducing device in which each of the cooling steam introduction pipes is provided with a temperature control valve or an ON-OFF valve.

  Further, according to the present invention, the cooling steam introduction pipe provided in the constricted portion of the temperature reducing pipe has a direction in which the superheated steam flows in the temperature reducing pipe in a connecting direction to the temperature reducing pipe. In contrast, the steam temperature reducing device is provided at right angles or obliquely along the flow direction.

  Further, according to the present invention, the temperature reducing pipe has a multistage orifice plate or fin in the direction of the flow of the superheated steam after the connection portion of the cooling steam introduction pipe in the direction of the flow of the superheated steam. Is a steam temperature reducing device.

  According to the invention, the superheated steam pipe is provided with a flow rate detector, the steam pipe is provided with a pressure detector, and the outputs of the pressure detector and the flow rate detector are connected to each other. A steam temperature reducing device characterized in that a device is arranged, calorific value is calculated by this control device, and a cold air control valve opening degree provided in the cooling steam introduction pipe is adjusted according to the calculation result It is.

  According to the present invention, low-pressure and low-temperature steam or steam obtained by flashing saturated water under reduced pressure can be sucked by the ejector effect of the steam temperature reducing device. Thereby, uniform and stable temperature-reduced steam can be obtained in a short time (short tube length).

  Further, since the cooling fluid is dispersed and mixed using a spray nozzle or the like, it is possible to eliminate the adverse effects caused by the thermal stress of the steam temperature reducing device, and the life of the steam temperature reducing device can be extended.

In the configuration of the steam down-raising device, squeezing a portion of the superheated steam pipe for flowing a high pressure at and high temperature superheated steam, at a location with higher steam flow rate, connect a pipe leading to the low pressure in and low-temperature cooling steam, reduced By utilizing the ejector effect of the warm pipe (suction effect by high flow rate), the low-pressure and low-temperature cooling steam is drawn into the inside of the temperature reducing pipe from the pipe and controlled so as to reach the specified temperature in the steam pipe. The temperature is reduced by mixing superheated steam and cooling steam.

  Hereinafter, a more specific example will be described.

  In FIG. 1, the schematic diagram of the steam temperature decreasing apparatus of Example 1 is shown. A superheated steam pipe 3, a steam temperature reducing device 1, and a steam pipe 4 communicate with each other along the flow path of the superheated steam 2. The superheated steam pipe 3 is formed so that the inner diameter, which is the flow path of the superheated steam 2, is substantially equal in diameter, and the steam pipe 4 and the inner diameter are both formed in substantially equal diameter. However, the inner diameter of the steam pipe 4 is formed larger than the inner diameter of the superheated steam pipe 3.

  In the steam temperature reducing device 1, a temperature reducing pipe 5 has a small nozzle shape at the center, one end communicates with the superheated steam pipe 3, and the other end communicates with the steam pipe 4. Accordingly, the inner diameters of the communicating portions 5a and 5b at both ends of the temperature reducing tube 5 are different. In addition, the temperature reducing tube 5 is formed with a constricted portion 5 c having an inner diameter smaller than the inner diameter of the superheated steam tube 3 at the center. A cooling steam introducing pipe 6 communicates with the constricted portion 5c. The cooling steam introduction pipe 6 is arranged in the flow direction of the superheated steam 2 (in the central axis direction of the temperature reduction pipe 5) so that the cooling steam 7 supplied to the temperature reduction pipe 5 can easily join the flow direction of the superheated steam 2. It is inclined and communicated along.

  The cooling steam introduction pipe 6 is provided with a check valve 8 and a temperature adjustment valve 9. The check valve 8 functions to prevent the superheated steam 2 having a higher pressure and higher temperature than the temperature reducing pipe 5 from flowing backward. The temperature adjustment valve 9 is connected to the output of the temperature adjustment meter 11. That is, the temperature controller 11 compares the signal of the temperature detector 12 that detects the steam temperature disposed in the steam pipe 4 with a preset temperature, and corrects the difference. A signal is transmitted to the temperature adjustment valve 9.

  With these configurations, the high-pressure and high-temperature superheated steam 2 that has passed through the superheated steam pipe 3 becomes a high-speed flow due to the ejector effect (suction effect by the high flow rate) due to the nozzle action of the temperature-reducing pipe 5, and the downstream steam pipe 4. It is sent to and flows in.

  Regarding the ejector effect, in principle, the pressure difference between low-pressure steam and high-pressure steam can be sucked into the high-pressure steam side. Changes. Therefore, since the suction effect is hindered when the differential pressure is larger, the flow rate is reduced.

At that time, in the steam temperature reducing device 1, a signal of the detection result of the temperature detector 12 that detects the steam temperature arranged in the steam pipe 4 is sent to the temperature control system 11, and the temperature control system 11 sets the specified setting. a control signal for correcting the difference between the temperature, that sends the temperature regulating valve 9. If correction is required, the opening of the temperature control valve 9 is adjusted to allow low-temperature and low-pressure cooling steam to flow from the cooling steam introduction pipe 6 to the temperature-reducing pipe 5 and join the high-temperature and high-pressure superheated steam 2. And mix. Thereby, control is performed so that the specified temperature required in the steam pipe 4 is obtained. From the steam pipe 4, the process steam 2 </ b> A whose temperature is reduced by the superheated steam 2 at the temperature required in the process of the plant is sent to the factory plant.

  Therefore, since the low-temperature and low-pressure cooling steam is used to reduce the temperature of the superheated steam 2, the time until evaporation is performed as in the conventional steam temperature reducing apparatus 1 that uses cooling water to reduce the temperature of the superheated steam 2. And the mixing with the superheated steam 2 is started earlier. In addition, since the temperature of the temperature reducing pipe 5 is reduced by heat exchange with the cooling water, the temperature difference from the non-evaporated water droplets is reduced, so that the thermal shock on the surface of the temperature reducing pipe 5 is alleviated. The

[Table 1] is numerical data of a specific example of the steam temperature reducing device 1 using cooling steam. That is, as the cooling steam, when the pressure is 13.6 at, the temperature is 321.5 ° C., the enthalpy is 738.3 kcal / kg, and the flow rate is 33.0 t / h, the superheated steam is 427 before the temperature reduction. Although it was .6 ° C., the temperature was reduced to 400.0 ° C. after the temperature was reduced by the cooling steam, and the enthalpy was reduced from 784.1 kcal / kg to 769.0 kcal / kg. On the other hand, the flow rate increases from 67.0 t / h to 100.0 t / h. These have confirmed the effect of reducing the temperature.

  FIG. 2 shows a schematic diagram of the steam temperature reducing apparatus of the second embodiment. The basic structure of the steam temperature reducing device 1 shown in FIG. 2 is the same as that of the steam temperature reducing device 1 shown in FIG.

  A superheated steam pipe 3, a steam temperature reducing device 1, and a steam pipe 4 communicate with each other along the flow path of the superheated steam 2. In FIG. 2, the temperature detector 12, the temperature controller 11, the temperature control valve 9 and the check valve 8 shown in FIG. 1 are omitted, but in actuality, they are arranged in the same manner as in FIG. Is provided.

  In the steam temperature reducing device 1 a, the temperature reducing pipe 5 has a nozzle shape, one end communicates with the superheated steam pipe 3, and the other end communicates with the steam pipe 4. Accordingly, the inner diameters of the communicating portions at both ends are different. In addition, the temperature reducing pipe 5 is formed with a constricted portion 5 c having an inner diameter smaller than the inner diameter of the superheated steam pipe 3 at the center. The constricted portion 5c is provided with a cooling steam introduction pipe 6 communicating in a direction substantially orthogonal to the flow direction of the heating steam (the central axis direction of the temperature reducing pipe 5). The cooling steam introduction pipe 6 is introduced with low-pressure stage bleed air (low-pressure and low-temperature cooling steam 7) from the turbine. The superheated steam pipe 3 is introduced with high-pressure extraction from the turbine (high-pressure and high-temperature superheated steam 2). The turbine 15 is supplied with main steam for rotation from a boiler (not shown) to rotate the generator 16.

  With these configurations, the high-pressure and high-temperature superheated steam 2 that has passed through the superheated steam pipe 3 becomes a high-speed flow due to the ejector effect (suction effect by the high flow rate) due to the nozzle action of the temperature-reducing pipe 5, and the downstream steam pipe 4. It is sent to and flows in.

  At that time, in the steam temperature reducing device 1, as shown in FIG. 1, a signal of the detection result of the temperature detector 12 for detecting the steam temperature arranged in the steam pipe 4 is sent to the temperature controller 11, and the temperature The controller 11 transmits a control signal for correcting the difference from the specified set temperature to the temperature control valve 9. When correction is required, the opening of the temperature control valve 9 is adjusted to allow low-pressure and low-temperature cooling steam to flow from the cooling steam introduction pipe 6 to the temperature-reduction pipe 5 to join the high-pressure and high-temperature superheated steam 2. And mix. Thereby, control is performed so that the specified temperature required in the steam pipe 4 is obtained. From the steam pipe 4, process steam 2A having a temperature required in the process of the plant is supplied to the plant of the factory.

  FIG. 3 shows a schematic diagram of the steam temperature reducing apparatus 1 of the third embodiment.

  In this case, the configuration is substantially the same as that of the second embodiment, except that a heat exchanger 17 is provided between the low-pressure stage extraction and the cooling steam introduction pipe 6. Therefore, in FIG. 3, the same functional parts as those in FIG.

  A cooling steam introduction pipe 6 is provided in the constricted portion 5 c of the temperature reducing pipe 5 so as to communicate in a direction substantially orthogonal to the flow direction of the superheated steam 2. Low-pressure stage bleed air (low-pressure and low-temperature cooling steam 7) from the turbine 15 is introduced into the cooling steam introduction pipe 6 through the heat exchanger 17 as generated steam of the heat exchanger 17. The superheated steam pipe 3 is introduced with a high-pressure stage bleed gas (high-pressure and high-temperature superheated steam 2) from the turbine 15. The turbine 15 is supplied with main steam for rotation from a boiler (not shown) to rotate the generator 16.

  With these configurations, the high-pressure and high-temperature superheated steam 2 that has passed through the superheated steam pipe 3 becomes a high-speed flow due to the ejector effect (suction effect by the high flow rate) due to the nozzle action of the temperature-reducing pipe 5, and the downstream steam pipe 4. It is sent to and flows in.

  At that time, in the steam temperature reducing device 1b, as shown in FIG. 1, a signal of the detection result of the temperature detector 12 for detecting the steam temperature arranged in the steam pipe 4 is sent to the temperature controller 11, and the temperature The controller 11 transmits a control signal for correcting the difference from the specified set temperature to the temperature control valve 9. When correction is required, the opening of the temperature regulating valve 9 is adjusted to allow the low-pressure and low-temperature cooling steam 7 to flow from the cooling steam introduction pipe 6 to the temperature-reduction pipe 5, and the high-pressure and high-temperature superheated steam 2. Combine and mix. Thereby, control is performed so that the specified temperature required in the steam pipe 4 is obtained. From the steam pipe 4, process steam 2A having a temperature required in the process of the plant is supplied to the plant of the factory.

  FIG. 4 shows a schematic diagram of the steam temperature reducing device 1 of the fourth embodiment.

  In this case, the configuration is substantially the same as in the third embodiment, but a heat exchanger 17 (for example, a multi-stage feed water superheater, a moisture separator, and a heat exchanger 17 provided between the low-pressure stage extraction and the cooling steam introduction pipe 6 is provided. The difference is that a pressure reducing valve 19 is disposed in the drain 18 of the drain tank or the like), and the steam that has been decompressed and flashed through the pressure reducing valve 19 is led to the cooling steam introduction pipe 6 and introduced into the steam pipe 4. Therefore, in FIG. 3, the same functional parts as those in FIG.

  In the power plant, a feed water superheater (heat exchanger 17) is provided in order to improve plant power generation efficiency. Saturated water generated by heat exchange is stored in this water heater.

  When the saturated water is depressurized, it flashes and becomes saturated steam, but a drain cooling zone (DCZ, not shown) is provided in the feed water superheater of the power plant, forcing the temperature down, It is discharged to the next stage feed water superheater in a drained state (if vaporized, the volume increases to about 1000 times that of the liquefied state, and a large-diameter pipe is required to flow the same flow rate. Dare to drain).

  Using this principle, steam can be obtained by forcibly reducing pressure by inserting a pressure reducing valve 19 into the drain 18 line of saturated water. The flash steam obtained from this saturated water is wet steam when the decompression ratio is low, and dry steam is obtained when the decompression ratio is high (generally referred to as the degree of superheat of steam).

  For example, the enthalpy of the drain 18 at 12.6 at 165.1 ° C. is 166.7 kcal / kg, whereas the enthalpy at 7.6 at a pressure reduced to 5.0 at 165.1 ° C. Becomes 663.7 kcal / kg and is in a vaporized state.

  Since the saturation temperature of 5.0ata is 151.1 ° C, steam having a superheat degree of 14.0 ° C (165.1-151.1 ° C) was obtained.

  That is, using these principles, the cooling steam introducing pipe 6 is provided in the constricted portion 5 c of the temperature reducing pipe 5 so as to communicate in a direction substantially orthogonal to the flow direction of the heating steam 2. In this cooling steam introduction pipe 6, low-pressure stage extraction air (low-pressure and low-temperature cooling steam) from the turbine 15 is introduced from the drain 18 of the heat exchanger 17 through the pressure reducing valve 19 as generated steam. . The superheated steam pipe 3 is introduced with a high-pressure stage bleed gas (high-pressure and high-temperature superheated steam 2) from the turbine 15. The turbine 15 is supplied with main steam for rotation from a boiler (not shown) to rotate the generator 16.

  With these configurations, the high-pressure and high-temperature superheated steam 2 that has passed through the superheated steam pipe 3 becomes a high-speed flow due to the ejector effect (suction effect by the high flow rate) due to the nozzle action of the temperature-reducing pipe 5, and the downstream steam pipe 4. It is sent to and flows in.

  At that time, in the steam temperature reducing device 1c, as shown in FIG. 1, a signal of the detection result of the temperature detector 12 for detecting the steam temperature arranged in the steam pipe 4 is sent to the temperature controller 11, and the temperature The controller 11 transmits a control signal for correcting the difference from the specified set temperature to the pressure reducing valve 19. When correction is required, the opening of the pressure reducing valve 19 is adjusted to allow low-pressure and low-temperature cooling steam to flow from the cooling steam introduction pipe 6 to the temperature-reducing pipe 5 and to merge with the high-pressure and high-temperature superheated steam 2. And mix. Thereby, control is performed so that the specified temperature required in the steam pipe 4 is obtained. From the steam pipe 4, process steam 2A having a temperature required in the process of the plant is supplied to the plant of the factory.

  FIG. 5 shows a schematic diagram of the steam temperature reducing apparatus of the fifth embodiment.

  In this case, although it is the structure substantially the same as the above-mentioned Example 1- Example 3, the points which each provided multiple cooling-vapor introduction pipes 6a, 6b, 6c differ. Therefore, in FIG. 5, the same reference numerals are given to the same functional portions as those in FIGS. 1 to 3, and the description thereof is omitted.

That is, a plurality of are provided in communication in the direction substantially perpendicular to the temperature reducing tube 5 of the constricted portion to 5c cooling steam inlet pipe 6a, 6b, 6c of overheating the steam 2 flow direction. Low-pressure stage extraction (low-pressure and low-temperature cooling steam) from the turbine 15 is branched and introduced into the cooling steam introduction pipes 6a, 6b, and 6c. The superheated steam pipe 3 is introduced with a high-pressure stage bleed gas (high-pressure and high-temperature superheated steam 2) from the turbine 15. The turbine 15 is supplied with main steam for rotation from a boiler (not shown) to rotate the generator 16.

  With these configurations, the high-pressure and high-temperature superheated steam 2 that has passed through the superheated steam pipe 3 becomes a high-speed flow due to the ejector effect (suction effect by the high flow rate) due to the nozzle action of the temperature-reducing pipe 5, and the downstream steam pipe 4. It is sent to and flows in.

  At that time, in the steam temperature reducing device 1d, as shown in FIG. 1, a signal of the detection result of the temperature detector 12 for detecting the steam temperature arranged in the steam pipe 4 is sent to the temperature controller 11, and the temperature The controller 11 transmits a control signal for correcting the difference from the specified set temperature to the pressure reducing valve 19. When correction is required, the opening of the pressure reducing valve 19 is adjusted to allow low-pressure and low-temperature cooling steam to flow from the cooling steam introduction pipe 6 to the temperature-reducing pipe 5 and to merge with the high-pressure and high-temperature superheated steam 2. And mix. Thereby, control is performed so that the specified temperature required in the steam pipe 4 is obtained. From the steam pipe 4, process steam 2A having a temperature required in the process of the plant is supplied to the plant of the factory.

  FIG. 6 shows a schematic diagram of a steam temperature reducing apparatus of Example 6.

  In this case, the configuration is substantially the same as in Example 5 described above, but a plurality of cooling steam introduction pipes 6d, 6e, and 6f are provided obliquely in the flow direction of the superheated steam 2 in the temperature reducing pipe 5. Is different. Therefore, in FIG. 6, the same functional parts as those in FIGS.

  That is, the constricted portion 5 c of the temperature reducing pipe 5 is provided with a plurality of cooling steam introduction pipes 6 d, 6 e, 6 f that communicate with each other in an oblique direction with respect to the flow direction of the heating steam 2. Low-pressure stage extraction (low-pressure and low-temperature cooling steam) from the turbine 15 is branched and introduced into the cooling steam introduction pipes 6d, 6e, and 6f. The superheated steam pipe 3 is introduced with a high-pressure stage bleed gas (high-pressure and high-temperature superheated steam 2) from the turbine 15. The turbine 15 is supplied with main steam for rotation from a boiler (not shown) to rotate the generator 16.

  With these configurations, the high-pressure and high-temperature superheated steam 2 that has passed through the superheated steam pipe 3 becomes a high-speed flow due to the ejector effect (suction effect by the high flow rate) due to the nozzle action of the temperature-reducing pipe 5, and the downstream steam pipe 4. It is sent to and flows in.

  At that time, in the steam temperature reducing device 1e, as shown in FIG. 1, the signal of the detection result of the temperature detector 12 for detecting the steam temperature arranged in the steam pipe 4 is sent to the temperature controller 11, and the temperature The controller 11 transmits a control signal for correcting the difference from the specified set temperature to the pressure reducing valve 19. When correction is required, the opening of the pressure reducing valve 19 is adjusted so that low-pressure and low-temperature cooling steam flows from the cooling-vapor introduction pipe 6 to the temperature-reducing pipe 5 and merges with the high-pressure and high-temperature superheated steam 2. And mix. Thereby, control is performed so that the specified temperature required in the steam pipe 4 is obtained. From the steam pipe 4, process steam 2A having a temperature required in the process of the plant is supplied to the plant of the factory.

  FIG. 7 shows a schematic diagram of a steam temperature reducing apparatus of Example 7. In FIG. 7, the temperature detector 12, the temperature controller 11, the temperature control valve 9, and the check valve 8 shown in FIG. 1 are omitted. Is provided.

  In this case, it relates to the internal structure of the temperature reducing pipe 5 of the steam temperature reducing device 1f. The temperature reducing pipe 5 has a nozzle shape, one end communicates with the superheated steam pipe 3, and the other end communicates with the steam pipe 4. Yes. Accordingly, the inner diameters of the communication portions 5a and 5b at both ends are different. In addition, the temperature reducing pipe 5 is formed with a constricted portion 5 c having an inner diameter smaller than the inner diameter of the superheated steam pipe 3 at the center. A cooling steam introducing pipe 6 communicates with the constricted portion 5c. The cooling steam introduction pipe 6 is communicated with an inclination along the flow direction of the superheated steam 2 so that the cooling steam supplied to the temperature reducing pipe 5 can easily join the flow direction of the superheated steam 2.

In addition, the orifice plate 21 provided with multi-stage orifices (not shown) in the direction perpendicular to the flow of the superheated steam 2 in the steam pipe 4 side from the constricted portion 5c of the temperature reducing pipe 5 turbulently flows the fluid. Fins (not shown) are provided for the purpose. Therefore, the low-pressure and low-temperature cooling steam 7 introduced from the superheated steam 2 and the cooling steam introduction pipe 6 is in a turbulent state, and mixing is promoted to obtain a temperature reduction effect.

  At that time, in the steam temperature reducing device 1f, as shown in FIG. 1, a signal of the detection result of the temperature detector 12 for detecting the steam temperature arranged in the steam pipe 4 is sent to the temperature controller 11, and the temperature The controller 11 transmits a control signal for correcting the difference from the specified set temperature to the pressure reducing valve 19. When correction is required, the opening of the pressure reducing valve 19 is adjusted to allow low-pressure and low-temperature cooling steam to flow from the cooling steam introduction pipe 6 to the temperature-reducing pipe 5 and to merge with the high-pressure and high-temperature superheated steam 2. Furthermore, the turbulent flow is further made when passing through the orifice plate 21 or a fin (not shown) for making the fluid turbulent. Thereby, control is performed so that the specified temperature required in the steam pipe 4 is obtained. From the steam pipe 4, the process steam 2 </ b> A having high accuracy with respect to the temperature required in the process of the plant is supplied to the factory plant.

  FIG. 8 shows a schematic diagram of a steam temperature reducing apparatus of Example 8.

  In this case, the configuration is substantially the same as that of the sixth embodiment described above, but the temperature is adjusted in each of the cooling steam introducing pipes 6d, 6e, and 6f provided obliquely in the flow direction of the superheated steam 2 in the temperature reducing pipe 5. The difference is that valves 9a, 9b, 9c or ON-OFF valves (not shown) are provided. Therefore, in FIG. 8, the same functional parts as those in FIGS. 1 to 3 and FIG.

  That is, the constricted portion 5 c of the temperature reducing pipe 5 is provided with a plurality of cooling steam introduction pipes 6 d, 6 e, 6 f that communicate with each other in an oblique direction with respect to the flow direction of the heating steam 2. Low-pressure stage extraction (low-pressure and low-temperature cooling steam) from the turbine 15 is branched and introduced into the cooling steam introduction pipes 6d, 6e, and 6f. The superheated steam pipe 3 is introduced with a high-pressure stage bleed gas (high-pressure and high-temperature superheated steam 2) from the turbine 15. The turbine 15 is supplied with main steam for rotation from a boiler (not shown) to rotate the generator 16.

  With these configurations, the high-pressure and high-temperature superheated steam 2 that has passed through the superheated steam pipe 3 becomes a high-speed flow due to the ejector effect (suction effect by the high flow rate) due to the nozzle action of the temperature-reducing pipe 5, and the downstream steam pipe 4. It is sent to and flows in.

  At that time, as shown in FIG. 1, the steam temperature reducing device 1 sends a detection result signal of the temperature detector 12 that detects the steam temperature arranged in the steam pipe 4 to the temperature controller 11, The controller 11 transmits a control signal for correcting the difference from the specified set temperature to each temperature adjusting valve 9. If correction is required, adjust the opening of each temperature control valve 9 (or adjust the ON-OFF time for an ON-OFF valve) and introduce low-temperature and low-temperature cooling steam into the cooling steam. By one or a combination of one or a plurality of pipes 6d, 6e, 6f, it flows into the temperature reducing pipe 5 and is combined with the high-pressure and high-temperature superheated steam 2 and mixed. Thereby, control is performed so that the specified temperature required in the steam pipe 4 is obtained. From the steam pipe 4, process steam 2A having a temperature required in the process of the plant is supplied to the plant of the factory.

  FIG. 9 shows a schematic diagram of a steam temperature reducing apparatus of Example 9.

  In this case, a new control system is added to the configuration of the second embodiment shown in FIG. Therefore, the same functional parts as those of the steam temperature reducing apparatus 1 shown in FIG.

In the steam temperature reducing device 1 h, the temperature reducing pipe 5 has a nozzle shape, one end communicates with the superheated steam pipe 3, and the other end communicates with the steam pipe 4. Accordingly, the inner diameters of the communicating portions at both ends are different. In addition, the temperature reducing pipe 5 is formed with a constricted portion 5 c having an inner diameter smaller than the inner diameter of the superheated steam pipe 3 at the center. The constricted portion 5c is provided with a cooling steam introduction pipe 6 communicating in an oblique direction with respect to the flow direction of the heating steam. The cooling steam introduction pipe 6 is introduced with low-pressure stage bleed air (low-pressure and low-temperature cooling steam) from the turbine 15. The superheated steam pipe 3 is introduced with a high-pressure stage bleed gas (high-pressure and high-temperature superheated steam 2) from the turbine 15. The turbine 15 is supplied with main steam for rotation from a boiler (not shown) to rotate the generator 16.

Furthermore, new control system is pressurized with. They are a flow rate detector 22 provided in the high-pressure and high-temperature superheated steam pipe 3, a pressure detector 23 provided in the steam pipe 4 fed to the process, a flow rate detector 22 and a pressure detector 23, The control device 24 that receives an output signal from, calculates a calorific value calculation (product of enthalpy and flow rate) based on the result, and issues a command to control the opening degree to the temperature control valve 9 according to the calculation result. It consists of and.

  With these configurations, the high-pressure and high-temperature superheated steam 2 that has passed through the superheated steam pipe 3 becomes a high-speed flow due to the ejector effect (suction effect by the high flow rate) due to the nozzle action of the temperature-reducing pipe 5, and the downstream steam pipe 4. It is sent to and flows in.

  At that time, the controller that receives the output signals from the flow rate detector 22 and the pressure detector 23 calculates the calorific value of the steam (the product of the enthalpy and its flow rate) from the received signal data, In response, a command for controlling the opening degree is issued to the temperature control valve 9. Thereby, the opening degree of the temperature control valve 9 is adjusted, and the low-pressure and low-temperature cooling steam flows from the cooling steam introduction pipe 6 into the temperature-reduction pipe 5 to be combined with the high-pressure and high-temperature superheated steam 2 and mixed. Let As a result, control is performed so that the specified temperature required for the steam pipe 4 is obtained. From the steam pipe 4, process steam 2A having a temperature required in the process of the plant is supplied to the plant of the factory.

  The calorific value of steam is determined by the product of the enthalpy of steam and its flow rate. That is, as shown in [Table 1], the steam pressure, temperature, and flow rate required after the temperature reduction (process side) are determined. The steam pressure / temperature before the temperature reduction and the cooling steam pressure / If the temperature is known, each flow rate can be calculated.

  That is, it can be calculated by the following equation along the explanatory diagram shown in FIG.

QL = {Q2 (H1-H2)} / (H2-HL)
Q: flow rate, H: enthalpy The enthalpy of each steam is the pressure and temperature, and can be determined from a known steam table. As a result, as described in [Table 1], the pressure before / after the temperature reduction is constant (controlled by the bleeder valve and the bleeder pressure reducing valve), so if the temperature is known, the enthalpy can be obtained. it can.

  In addition, as an example of a factory plant using process steam having a predetermined temperature sent from the steam pipe 4 in each of the above-described embodiments, a paper mill plant or the like can be cited.

The schematic diagram of the steam temperature reducing apparatus of the Example of this invention. The schematic diagram of the steam temperature reducing apparatus of the Example of this invention. The schematic diagram of the steam temperature reducing apparatus of the Example of this invention. The schematic diagram of the steam temperature reducing apparatus of the Example of this invention. The schematic diagram of the steam temperature reducing apparatus of the Example of this invention. The schematic diagram of the steam temperature reducing apparatus of the Example of this invention. The schematic diagram of the steam temperature reducing apparatus of the Example of this invention. The schematic diagram of the steam temperature reducing apparatus of the Example of this invention. The schematic diagram of the steam temperature reducing apparatus of the Example of this invention. Explanatory drawing regarding calculation of calorie | heat amount calculation of steam. The schematic diagram of the steam temperature reducing apparatus of the conventional Example.

Explanation of symbols

1, 1C～1h ... steam down-raising device, 2 ... superheated steam, 2A ... process steam, 3 ... overheating steam pipe, 4 ... steam pipe, 5 ... reduced temperature pipe, 5c ... constriction, 6,6A～6f ... cooling steam inlet pipe, 7 ... cooling steam, 9, 9a to 9c ... thermostatic valve, 11 ... temperature controller, 12 ... temperature detector, 15 ... turbine, 17 ... heat exchanger, 18 ... drain Lee down, 19 ... Pressure reducing valve, 21 ... orifice plate, 22 ... flow rate detector, 23 ... pressure detector, 24 ... control device

Claims (10)

A superheated steam pipe for allowing superheated steam, which is a high-pressure stage bleed of the turbine, to flow into the inside of the temperature reducing pipe is connected to one side end so as to form a conduit integrally with the temperature reducing pipe, and the temperature reducing temperature is connected to the other side end. A steam temperature reducing device in which a steam pipe into which the steam discharged from the pipe flows in is communicated with the temperature reducing pipe so as to form a conduit integrally therewith,
The temperature reducing pipe has a nozzle shape in which a constricted portion having a smaller inner diameter at the center than the both side ends is formed, and in the constricted portion, cooling steam that is a low-pressure stage extraction of the turbine is placed in the temperature reducing pipe. It provided cooling steam introduction pipe for introducing the said inner diameter of the communication portion that is connected to the steam pipe before Symbol decreased temperature tube is formed as a large consisting inner diameter of the constricted portion, the vapor of the reduced temperature tube The internal diameter of the communication part connected to the pipe is formed to be larger than the internal diameter of the communication part connected to the superheated steam pipe of the temperature reducing pipe, and the cooling steam supplied to the cooling steam introduction pipe is : The steam pipe is drawn into the temperature reducing pipe by the ejector effect of the nozzle action of the temperature reducing pipe, which is set at a lower pressure and lower temperature than the superheated steam, and the high temperature and high temperature superheated steam that has passed through the superheated steam pipe flows. Turkey to flows been blown to Steam down raising device according to claim.   The steam pipe is provided with a temperature detector, the output of the temperature detector is connected to a temperature controller, and the output of the temperature controller is an opening of a temperature control valve provided in the cooling steam introduction pipe. The steam temperature reducing device according to claim 1, wherein the temperature is adjusted.   The steam temperature reducing device according to claim 1, wherein high pressure stage extraction from a turbine is introduced into the superheated steam pipe, and low pressure stage extraction from a turbine is introduced into the cooling steam pipe.     The steam temperature reducing device according to claim 1, wherein the cooling steam uses steam generated by a heat exchanger connected to the cooling steam introduction pipe.     The steam cooling temperature according to claim 1, wherein the cooling steam uses steam that has been decompressed and flushed by a temperature control valve via a drain of a heat exchanger connected to the cooling steam introduction pipe. apparatus.     The steam temperature reducing device according to claim 1, wherein a plurality of the cooling steam introducing pipes provided in the constricted portion of the temperature reducing pipe are provided.     The steam temperature reducing device according to claim 6, wherein each of the cooling steam introduction pipes is provided with a temperature control valve or an ON-OFF valve.     The cooling steam introduction pipe provided in the constricted portion of the temperature reducing pipe is perpendicular to or flows in the direction in which the superheated steam flowing through the temperature reducing pipe flows in the connecting direction to the temperature reducing pipe. The steam temperature reducing device according to claim 1, wherein the steam temperature reducing device is provided obliquely along the direction.     Inside the temperature reducing pipe, a multistage orifice plate or fin is provided in the direction in which the superheated steam flows after the connection portion of the cooling steam introduction pipe in the direction in which the superheated steam flows. The steam temperature reducing device according to claim 1, wherein     The superheated steam pipe is provided with a flow rate detector, the steam pipe is provided with a pressure detector, and a control device to which outputs of the pressure detector and the flow rate detector are connected is provided. 2. The steam temperature reducing device according to claim 1, wherein a calorific value is calculated by a control device, and a cold air control valve opening degree provided in the cooling steam introduction pipe is adjusted according to the calculation result.

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