JPWO2015133428A1 - Steam system - Google Patents

Abstract

To provide a steam system capable of generating new power using drain generated in a heat exchanger (steam use section). The steam system 1 includes a steam circuit 10 having a heat exchanger 22 (steam use unit) in which steam dissipates heat to an object and condenses. The steam circuit 10 includes an expander 24 that receives drain (condensate) generated by condensation of steam in the heat exchanger 22 and expands the drain to generate power.

Description

  The present application relates to a steam system for heating an object with steam.

  For example, as disclosed in Patent Document 1, a steam system (steam heating device) that heats an object with steam is known. The steam system includes a heat exchanger that exchanges heat between the steam and an object, and a drain storage section (header tank). In this steam system, steam flowing in the heat exchanger dissipates heat to the object and condenses to become drain (condensate). Thereby, a target object is heated (latent heat heating). And the drain which generate | occur | produced with the heat exchanger is sent to a storage part, and is stored. The drain in the reservoir is returned to the water supply tank or discharged to the outside according to the temperature. The drain returned to the water supply tank is regenerated into steam.

JP 2013-169477 A

  By the way, in the conventional steam system, the drain (condensate) generated in the heat exchanger is reused as a steam generation source as described above. On the other hand, the drain generated in the heat exchanger is used to generate power. Therefore, there was a request to reuse and save energy.

  The technology disclosed in the present application has been made in view of such circumstances, and an object thereof is to provide a steam system capable of generating new power by using drain generated in a steam using part such as a heat exchanger. It is in.

  In order to achieve the above object, the technology disclosed in the present application generates power by re-evaporating (flushing) the drain, which is a liquid generated in the vapor using portion, and expanding it.

  Specifically, the technique disclosed in the present application is premised on a steam system including a steam circuit having a steam use unit that radiates and condenses steam to an object. And the said steam circuit has the expander which the drain which generate | occur | produced by condensation of the steam in the said steam use part flows in, expands this drain, and generates motive power.

  As described above, according to the steam system of the present application, since the expander that expands the drain (condensate) generated by the condensation of the steam in the steam using part is provided, new power is generated using the drain. It is possible to provide a steam system capable of. Therefore, for example, by connecting the generator to the expander, the generator can be driven by the power generated by the expander. And the energy saving of a steam system can be achieved by using the electric power generated with the generator.

FIG. 1 is a circuit diagram illustrating a schematic configuration of a steam system according to the first embodiment. FIG. 2 is a circuit diagram illustrating a schematic configuration of the steam system according to the second embodiment. FIG. 3 is a circuit diagram illustrating a schematic configuration of a steam system according to a modification of the second embodiment. FIG. 4 is a circuit diagram illustrating a schematic configuration of the steam system according to the third embodiment.

  Hereinafter, embodiments of the present application will be described with reference to the drawings. Note that the following embodiments are essentially preferable examples, and are not intended to limit the scope of the technology disclosed in the present application, applications thereof, or uses thereof.

(Embodiment 1)
A first embodiment of the present application will be described. The steam system 1 of the present embodiment heats an object (for example, a reaction kettle) with steam (saturated steam). As shown in FIG. 1, the steam system 1 includes a steam circuit 10 through which steam flows. The steam circuit 10 includes a steam generation unit 21, a heat exchanger 22, and a steam trap 23.

  The steam generation unit 21 generates water (saturated steam) by heating water. The heat exchanger 22 has an inlet 22 a connected to the steam generator 21 through the inflow pipe 11 and an outlet 22 b connected to the inlet 23 a of the steam trap 23 through the outflow pipe 12.

  In the heat exchanger 22, the steam supplied from the steam generating unit 21 dissipates heat to the object and condenses, and the object is heated. The steam becomes drain (condensate) by condensing. That is, the heat exchanger 22 is a latent heat exchanger that heats an object by latent heat of condensation of the steam (latent heat heating), and constitutes a steam using unit according to the claims of the present application.

  In the steam trap 23, drain (condensate) generated by condensation of steam in the heat exchanger 22 or drain mixed with steam (condensate) flows through the inlet 23 a. The steam trap 23 automatically discharges only the drained water from the outlet 23b.

  Further, the steam circuit 10 of the present embodiment further includes an expander 24 and a generator 28. The expander 24 is connected to the outlet portion 23 b of the steam trap 23 through the inflow pipe 13. That is, in the steam circuit 10, the steam trap 23 is provided between the heat exchanger 22 and the expander 24, and the steam trap 23 discharges only the drained flow toward the expander 24.

  The expander 24 is a scroll expander having a casing 25 and an expansion mechanism 26 accommodated in the casing 25. Although not shown, the expansion mechanism 26 has a fixed scroll wrap and a movable scroll (orbiting scroll) lap engaged with each other to form an expansion chamber. The inflow pipe 13 is connected to the inlet 26a of the expansion mechanism 26, and the outflow pipe 14 is connected to the outlet 26b. The expansion mechanism 26 is provided with an output shaft 27.

  In the expansion mechanism 26, the drain discharged from the outlet portion 26b of the steam trap 23, that is, the drain generated by the condensation of the steam in the heat exchanger 22, flows into the expansion chamber from the inlet portion 26a. The expansion mechanism 26 is configured to generate power by expanding the drain that has flowed into the expansion chamber. Specifically, when the drain which is a liquid phase flows into the expansion chamber, the pressure is reduced, so that it is re-evaporated (flashed) to become vapor which is a gas phase again. That is, the volume of the drain expands. The volume of the expansion chamber increases with the volume expansion of the drain, and the output shaft 27 is rotationally driven by the increase in the volume of the expansion chamber. That is, in the expansion mechanism 26, rotational power is generated by re-evaporating (flushing) the drain and transmitted to the output shaft 27.

  Thus, although the drain which is a liquid phase flows into the expander 24, since the drain is a saturated state, the drain can be easily re-evaporated (flashed). As a result, the drain can be easily expanded. The expanded drain (that is, steam) flows out to the outflow pipe 14 from the outlet portion 26b.

  Strictly speaking, since some of the drain discharged from the outlet 23b of the steam trap 23 is re-evaporated (flushed) while flowing through the inflow pipe 13, the expander 24 has some steam together with the drain. Flows in. In the expander 24, not only the drained inflow but also the steam expands, and the volume of the expansion chamber increases.

  The generator 28 has a drive shaft 29 connected to the output shaft 27 of the expander 24. The generator 28 is driven by the output shaft 27 of the expander 24 to generate power. That is, in the steam system 1, the power generated by the expander 24 is used as a drive source for the generator 28.

  As described above, the steam system 1 according to the first embodiment includes the expander 24 that flows in the drain (condensate) generated by the condensation of steam in the heat exchanger 22 and expands the drain to generate power. I did it. Therefore, it is possible to provide the steam system 1 capable of generating new power using the drain generated in the heat exchanger 22.

  Then, the generator 28 can be driven by the rotational power generated by the expander 24 by connecting the generator 28 to the output shaft 27 of the expander 24 as in the first embodiment. Then, by supplying the electric power generated by the generator 28 to an electric motor or the like used in the steam system 1, energy saving of the entire apparatus can be achieved.

  Moreover, according to the said Embodiment 1, since the steam trap 23 was provided between the heat exchanger 22 and the expander 24, only drain (condensate) can be sent toward the expander 24. FIG. As described above, some of the drain is re-evaporated (flashed) before flowing into the expander 24 to become vapor and flow into the expansion chamber of the expander 24, and the steam trap 23 is provided so that only the drain is discharged. The amount of steam flowing into the expansion chamber can be reduced by sending toward the exhaust as compared with the case where drain and steam are sent toward the expander. In other words, the amount of drain flowing into the expansion chamber can be increased. That is, the proportion of drain in the expansion chamber can be increased. As a result, the expansion rate in the expander 24 can be earned. That is, the expansion rate of the vapor is extremely lower than the expansion rate when the drain evaporates. However, in the first embodiment, since the amount of drain inflow can be increased, the expansion rate in the expander 24 can be increased. .

  Actually, in the inflow pipe 11 and the outflow pipe 12, a part of the steam may condense and become drainage. In the steam system 1 of the first embodiment, the drain flowing into the expander 24 includes not only the drain generated in the heat exchanger 22 but also the drain generated in the inflow pipe 11 and the outflow pipe 12.

(Embodiment 2)
A second embodiment of the present application will be described. As shown in FIG. 2, the steam system 1 of the present embodiment is obtained by changing the configuration of the steam circuit 10 in the first embodiment. That is, the steam circuit 10 of the present embodiment includes a plurality of (six in this embodiment) steam use systems instead of the first embodiment having one heat exchanger and one steam trap. , A drain collecting portion 43. Here, differences from the first embodiment will be described.

  Each of the six steam use systems has a heat exchanger 41 and a steam trap 42. The steam generation unit 21 is connected to six steam use systems via the inflow pipe 31. That is, the inflow pipe 31 is branched into six and connected to the steam use system. In addition, the number of the steam use systems mentioned above is only an example, and this embodiment should just have two or more steam use systems.

  In each steam use system, the heat exchanger 41 has an inlet connected to the steam generator 21 via the inflow pipe 31 and an outlet connected to the inlet of the steam trap 42 via the outflow pipe 32. Each of the heat exchanger 41 and the steam trap 42 has the same configuration and function as those of the first embodiment.

  The drain collecting portion 43 is a relatively elongated tubular container. The drain collecting portion 43 is connected to each of the six steam use systems via the inflow pipe 33. That is, the inflow pipe 33 is connected between the outlet portion of the steam trap 42 and the drain collecting portion 43. In the drain collecting part 43, the drain generated by the condensation of the steam in the heat exchanger 41 of each steam use system flows and gathers. The steam trap 42 discharges only the drain toward the drain collecting portion 43.

  A drain discharge pipe 34 is connected to the bottom of the drain collecting portion 43. The drain discharge pipe 34 discharges the drain of the drain collecting portion 43. Actually, in the drain collecting portion 43, a part of the drain evaporates to become steam, and the steam is discharged to the drain discharge pipe 34 together with the drain.

  Moreover, the steam circuit 10 of this embodiment also has the expander 24 and the generator 28 similarly to the said Embodiment 1. FIG. A drain discharge pipe 34 is connected to the inlet portion 26 a of the expansion mechanism 26. In the expansion mechanism 26, the drain discharged from the drain collecting portion 43, that is, the drain generated by the condensation of the steam in the heat exchanger 41 flows into the expansion chamber from the inlet portion 26a. In the expansion mechanism 26, as in the first embodiment, power is generated by expanding the drain that has flowed into the expansion chamber. Also in this embodiment, since the drain flowing into the expander 24 is in a saturated state, the drain can be easily re-evaporated (flashed).

  Strictly speaking, since some of the drain discharged from the drain collecting portion 43 is re-evaporated (flashed) while flowing through the drain discharge pipe 34, some steam flows into the expander 24 together with the drain. To do. In the expander 24, not only the drained inflow but also the steam expands, and the volume of the expansion chamber increases.

  As described above, in the steam system 1 according to the second embodiment, the drain collecting portion 43 that collects and collects drains generated in a plurality of steam using systems having the heat exchanger 41 is provided. And downsizing of the apparatus can be achieved.

  Furthermore, in the steam system 1 of the second embodiment, the drain (condensate) of the drain collecting portion 43 flows in, and the expander 24 that expands the drain to generate power is provided. Therefore, the steam system 1 that can generate new power using the drain of the drain collecting portion 43 can be provided.

  Further, the operation time of the plurality of steam use systems varies depending on the operating conditions, that is, the plurality of steam use systems have different drain generation times. However, since the drain generated in these steam-using systems is collected in one drain collecting portion 43, it becomes easy to always secure a certain amount of drain in the drain collecting portion 43. Then, since the drain can be supplied to the expander 24 for as long as possible, the expander 24 can be driven for a long time. As a result, the generated power can be earned.

  Further, according to the second embodiment, since the steam trap 42 is provided on the downstream side of the heat exchanger 41 in each steam use system, only drain (condensate) can be sent toward the drain collecting portion 43. . Therefore, for example, a larger amount of drain can be secured in the drain assembly portion 43 than in the case where a mixed fluid of steam and drain is sent toward the drain assembly portion 43. Accordingly, since the drain can be supplied to the expander 24 for as long as possible, the expander 24 can be driven for a long time.

  Further, in the second embodiment, even if any of the plurality of steam traps 42 fails and the drain cannot be discharged, the drain is discharged from the other normal steam traps 42. Can be secured. Other configurations, operations, and effects are the same as those of the first embodiment.

(Modification of Embodiment 2)
A modification of the second embodiment will be described with reference to FIG. In this modification, the steam in the drain collecting portion 43 is caused to flow into the expander 24 together with the drain in the steam system 1 of the second embodiment. Specifically, one end of the steam discharge pipe 35 is connected to the top of the drain collecting portion 43, and the other end of the steam discharge pipe 35 is connected in the middle of the drain discharge pipe 34. In the drain collecting portion 43, the drain is mainly discharged to the drain discharge pipe 34 and the steam is discharged to the steam discharge pipe 35.

  In this modification, in addition to the drain of the drain collecting portion 43, steam can also flow into the expander 24. This is effective when the drain amount of the drain collecting portion 43 is small and a sufficient amount of drain cannot flow into the expander 24. That is, since the steam flowing into the expander 24 expands although the expansion rate is lower than that of the drain, it is possible to compensate for the insufficient expansion of the drain as much as possible. Therefore, even if the amount of drain supply to the expander 24 decreases, it is possible to suppress the decrease in the power generated by the expander 24 as much as possible. In this modification, an opening / closing valve may be provided in the steam discharge pipe 35 so that the steam is discharged from the drain collecting portion 43 by opening the opening / closing valve only when the drain amount of the drain collecting portion 43 is small. Other configurations, operations, and effects are the same as those of the second embodiment.

  In the second embodiment, in reality, a part of the vapor may be condensed in the inflow pipe 31 and the outflow pipe 32 to become drain. In the steam system 1 of the second embodiment, the drain flowing into the drain collecting portion 43 includes not only the drain generated in the heat exchanger 41 but also the drain generated in the inflow pipe 31 and the outflow pipe 32.

(Embodiment 3)
A third embodiment of the present application will be described. As shown in FIG. 4, the steam system 1 according to the present embodiment includes a flash tank 62 in the steam circuit 10 according to the first embodiment. Here, differences from the first embodiment will be described.

  The heat exchanger 22 has an outlet 22 b connected to the steam trap 61 via the outflow pipe 12. The steam trap 61 has the same configuration and function as those of the first embodiment. The steam trap 61 is provided between the heat exchanger 22 and a flash tank 62 described later, and discharges only the drain toward the flash tank 62.

  The flash tank 62 has an inlet 62 a connected to the steam trap 61 via the inflow pipe 51. In the flash tank 62, drain discharged from the steam trap 61, that is, drain (condensate) generated by condensation of steam in the heat exchanger 22 flows through the inlet 62a. The flash tank 62 is configured to evaporate part of the drained drain. The inside of the flash tank 62 has a low-pressure atmosphere having a lower pressure than the high-pressure drain flowing out from the heat exchanger 22 by providing the steam trap 61 on the upstream side. In the flash tank 62, a part of the drained inflow is re-evaporated (flashed) by decompression to become low-pressure steam (flash steam), and the remaining drain becomes low-pressure drain. That is, the drain is depressurized and the temperature (saturation temperature) is lowered, and the heat corresponding to the lowered temperature is used as the latent heat of evaporation of the drain. Thus, the inside of the flash tank 62 is divided into a liquid layer of low-pressure drain and a gas layer of low-pressure steam.

  The flash tank 62 is provided with a first outlet 62b that communicates with the liquid layer of low-pressure drain and a second outlet 62c that communicates with the gas layer of low-pressure steam. The first outlet portion 62 b is connected to the expander 24 through the drain discharge pipe 52. One end of the steam discharge pipe 55 is connected to the second outlet 62c, and the other end of the steam discharge pipe 55 is connected to a low pressure line. The drain discharge pipe 52 discharges low-pressure drain from the flash tank 62, and the steam discharge pipe 55 discharges low-pressure steam from the flash tank 62. The steam discharge pipe 55 is provided with a check valve 65 that allows only a flow toward the low pressure line. Although not shown, the low-pressure steam that has flowed through the low-pressure line is supplied to, for example, a low-pressure heat exchanger and dissipates heat to an object other than the object described above, and condenses.

  The flash tank 62 is provided with a liquid level gauge 63 and a pressure gauge 64. The liquid level gauge 63 measures the liquid level height of the low pressure drain in the flash tank 62, and the pressure gauge 64 measures the pressure of the low pressure steam in the flash tank 62 (corresponding to the internal pressure of the flash tank 62).

  The steam circuit 10 of the present embodiment also has an expander 24 and a generator 28. A drain discharge pipe 52 is connected to the inlet portion 26 a of the expansion mechanism 26. In the expansion mechanism 26, the low-pressure drain discharged from the first outlet 62b of the flash tank 62 flows into the expansion chamber from the inlet 26a. In the expansion mechanism 26, as in the first embodiment, power is generated by expanding the drain that has flowed into the expansion chamber. Also in this embodiment, since the drain flowing into the expander 24 is in a saturated state, the drain can be easily re-evaporated (flashed).

  Strictly speaking, since some of the drain discharged from the first outlet 62b of the flash tank 62 is re-evaporated (flushed) while flowing through the drain discharge pipe 52, the expander 24 has some of the drain together. Some steam flows in. In the expander 24, not only the drained inflow but also the steam expands, and the volume of the expansion chamber increases.

  As described above, in the steam system 1 of the third embodiment, the drain generated in the heat exchanger 22 is re-evaporated (flashed) in the flash tank 62, and the low-pressure steam is supplied to the low-pressure line and reused as a heat source. Therefore, a part of the heat of the drain generated in the heat exchanger 22 can be recovered, so that energy saving can be achieved.

  Further, in the steam system 1 of the third embodiment, the expander 24 that generates the power by injecting the drain (condensate) of the flash tank 62 and expanding the drain. Therefore, the steam system 1 capable of generating new power using the drain of the flash tank 62 can be provided.

  In the third embodiment, since the steam trap 61 is provided between the heat exchanger 22 and the flash tank 62, the inside of the flash tank 62 can be surely made into a low-pressure atmosphere. Therefore, a part of the drain that has flowed into the flash tank 62 can be reliably evaporated (flashed). Other configurations, operations, and effects are the same as those of the first embodiment.

  Actually, as described in the first embodiment, a part of the vapor may be condensed in the inflow pipe 11 and the outflow pipe 12 to be drained. In the steam system 1 of the third embodiment, the drain flowing into the flash tank 62 includes not only the drain generated in the heat exchanger 22 but also the drain generated in the inflow pipe 11 and the outflow pipe 12.

  Moreover, although the said Embodiment 3 demonstrated the form provided with the heat exchanger 22 and the flash tank 62 one each, in the steam system 1 of this embodiment, each number is not restricted to this. For example, a plurality of heat exchangers may be provided, and one flash tank corresponding to all the heat exchangers may be provided, or one flash tank may be provided for each heat exchanger. . Even in this case, a steam trap is provided upstream of each flash tank as in the above embodiment.

(Other embodiments)
The steam system of the present application may be configured as follows in the above embodiment.

  First, in the above embodiment, the generator 28 is connected to the output shaft 27 of the expander 24. However, the present application is not limited to this, and other rotating devices such as other pumps used in the steam system 1, for example. May be coupled to the output shaft 27 of the expander 24. By doing so, it is possible to reduce energy consumption for driving the rotating device.

  Further, in the above embodiment, the scroll type is used as the expander 24, but a so-called turbine type (also referred to as an expansion turbine) may be used. Although not shown, the expansion mechanism 26 of the turbine expander 24 includes a nozzle communicating with the inlet portion 26 a and a turbine blade (impeller) coupled to the output shaft 27. In the expansion mechanism 26, the drain that flows in from the inlet portion 26a is ejected by the nozzle and collides with the turbine blade. The drain is accelerated and depressurized by passing through the nozzle. When the drain is depressurized, the volume expands by re-evaporating (flushing) as described in the above embodiment. In addition, since the drain is accelerated, the impulsive force of the drain with respect to the turbine blade increases. The turbine blades are rotationally driven by the volume expansion and impulse of the drain, and the rotational power is transmitted to the output shaft 27. As described above, in the case of the turbine-type expander 24, the same effects as those of the above-described embodiment are obtained. In addition, the expander 24 may be a rotary type or a screw type.

  In the above embodiment, the expanded drain (that is, the steam) that has flowed out of the expander 24 to the outflow pipe 14 may be recovered and reused, for example, as water in the steam generation unit 21.

  Moreover, in said embodiment, although the case where a vapor | steam using part was the heat exchangers 22 and 41 was demonstrated, if the vapor | steam using part which concerns on the claim of this application is a thing which heat | fever dissipates and condenses a target It can be anything. For example, the steam use section according to the claims of the present application may be one that heat-sterilizes an empty bottle or the like with steam, or one that wraps a steam pipe around the oil transport pipe and heats and heats the oil with steam.

  In the above embodiment, the lengths of the inflow pipe 13 and the drain discharge pipes 34 and 52 connected to the expander 24 are preferably as short as possible from the viewpoint of suppressing drain re-evaporation (flash). This is because the longer the inflow pipe 13 and the like, the more the pressure loss of the drain increases and the drain becomes easier to re-evaporate. By suppressing the re-evaporation of the drain in the inflow pipe 13 or the like, the amount of drain flowing into the expander 24 can be earned. As a result, the expansion rate in the expander 24 can be increased.

  The technique disclosed in the present application is useful for a steam system in which an object is latently heated with steam.

1 Steam System 10 Steam Circuit 22 Heat Exchanger (Steam Use Section)
23 Steam trap 24 Expander 41 Heat exchanger (steam use part, steam use system)
42 Steam trap (steam system)
43 Drain collecting part 61 Steam trap 62 Flash tank

Claims (8)

A steam system having a steam circuit having a steam use part that radiates and condenses steam to an object,
The steam system according to claim 1, wherein the steam circuit has an expander that generates a power by inflowing drain generated by condensation of steam in the steam using part and expanding the drain. The steam system according to claim 1,
The steam system is provided with a steam trap that is provided between the steam use section and the expander and discharges only the drain toward the expander. The steam system according to claim 1,
The steam circuit has a plurality of steam use systems having the steam use part, and a drain collection part in which drains generated by condensation of steam in the steam use parts of the plurality of steam use systems gather,
The expander is a steam system characterized in that drain of the drain collecting portion flows in and expands the drain to generate power. The steam system according to claim 3,
In the expander, the steam generated by evaporating the drain in the drain collecting portion flows together with the drain in the drain collecting portion. The steam system according to claim 3 or 4,
The steam system, wherein the plurality of steam use systems includes a steam trap that is provided on the downstream side of the steam use part and discharges only the drain toward the drain collecting part. The steam system according to claim 1,
The steam circuit has a flash tank in which drain generated by condensation of steam flows in the steam using part, and evaporates a part of the drain,
The expander is a steam system, wherein drain of the flash tank flows in and expands the drain to generate power. The steam system according to claim 6.
The steam system is provided with a steam trap that is provided between the steam use section and the flash tank and discharges only the drain toward the flash tank. The steam system according to any one of claims 1 to 7,
The expander is a turbine-type expander.

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