JP2010203730A - Steam generation system using waste heat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a steam generation system A using waste heat capable of manufacturing low-pressure steam from the waste heat discharged from factories, etc., and expanding applications of the waste heat by boosting the low-pressure steam. <P>SOLUTION: The steam generation system A includes a heat pump 10 as a first steam generation source B, a boiler 20 which is a second steam generation source composing a middle-pressure steam manufacturing means C, and an ejector 30 as a steam boosting device. The ejector 30 is supplied with second steam from the boiler 20 as driving steam, and also supplied with first steam from the heat pump 10 as suction steam. While utilizing the waste heat, middle-pressure discharge steam around 0.1-1.0 MPa widely used in factories as a heat source can be obtained from the ejector 30 thereby. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a steam generation system in which low-pressure steam is produced from exhaust heat generated from a factory or the like and the pressure of the low-pressure steam is increased.

  Much waste heat is generated from factories. Exhaust heat is, for example, jacket cooling water in a cogeneration system that uses a gas engine as a power source, steam ring water from steam used in factories or hospitals, hot water recovered from exhaust gas from boilers, solid / liquid systems, etc. In many cases, it is taken out in the form of warm water (hereinafter referred to as waste hot water), such as warm water generated when liquid is cooled. In normal cases, the temperature of the exhaust hot water obtained from the exhaust heat is 90 ° C. or less.

  These waste water is used effectively for the heat source of an absorption refrigerator, the preheating of boiler feed water, etc. For example, in patent document 1, waste water is utilized as a heat source of an absorption refrigerator. However, medium-pressure steam of about 0.1 to 1.0 MPa (G) is required for heat utilization in general factories, and positive pressure steam is obtained only from the exhaust water having a temperature of 90 ° C. or less as described above. Cannot be manufactured and its use must be very limited. As a result, a large amount of exhaust heat is dissipated without being used.

  As one solution, Patent Document 2 and Patent Document 3 propose using a heat pump to generate low-pressure steam using waste hot water as a heat source. Although it is possible to expand the use of waste hot water by using a heat pump, the pressure of the generated steam is about 0.1 MPa (G) at present, and since the use is limited as it is, factories, etc. Has not yet been widely used.

JP 1999-325646 A JP 2007-232313 A JP 2007-232357 A

  The present invention has been made in view of the current situation as described above, and aims to expand the use of exhaust heat emitted from factories and the like, and more specifically, utilizes exhaust heat emitted from factories and the like. An object of the present invention is to realize a steam generation system using exhaust heat that can increase the pressure of the low-pressure steam obtained in this way to higher-pressure steam, thereby expanding the use of exhaust heat.

  A steam generation system using exhaust heat according to the present invention that solves the above problems uses a first steam generation source that produces first steam from first exhaust heat, and uses the first steam as suction steam. Medium pressure steam producing means, and discharge steam having a pressure higher than that of the first steam is obtained from the medium pressure steam producing means.

  Although not limited, the first exhaust heat is preferably a jacket cooling water of a cogeneration system using a gas engine or the like as a power source, or steam ring water from steam used in a factory or a hospital. As the steam generation source, one having a temperature raising system using a heat pump is suitable. Although not limited, the second type absorption heat pump is suitable as the heat pump, and the system can be easily controlled by using the heat pump.

  In a more specific first form of the steam generation system using exhaust heat according to the present invention, the intermediate-pressure steam production means uses a second heat source different from the first exhaust heat from the first steam. The second steam generating source for producing the second steam having a high pressure and the steam booster using the second steam as the driving steam. The steam booster is supplied with the first steam as suction steam, and the steam booster uses the second steam as driving steam to produce medium-pressure discharge steam. The discharged steam has a higher pressure than the first steam and a lower pressure than the second steam.

  In the first embodiment, the energy required for the operation of the steam generation system can be basically obtained from the energy of the exhaust heat, the exhaust heat can be used effectively, and energy saving can be achieved. Although not limited, the heat which the exhaust gas of the internal combustion engine which is fuel combustion gas, a gas engine, etc. has is suitably used for the said 2nd heat source. In that case, a boiler or an engine exhaust gas boiler is suitably used as the second steam generation source. In addition, as the steam booster, an ejector or a steam-driven compressor is preferably used.

  In a more specific aspect of the steam generation system using exhaust heat of the above form, the first exhaust heat uses heat of exhaust water from an internal combustion engine such as a gas engine, and the second exhaust heat. The exhaust gas from the same internal combustion engine is used as the heat source. The internal combustion engine is not limited, but may be an internal combustion engine such as a gas engine as a drive source in a cogeneration system. This system can further improve the overall efficiency of the cogeneration system.

  In a more specific second embodiment of the steam generation system using exhaust heat according to the present invention, the intermediate-pressure steam producing means is an external power drive compressor. As the external power drive compressor, an electric drive compressor or an engine drive compressor is preferably used. And also in this form, as discharge steam obtained from the said intermediate pressure steam production means, Preferably, the intermediate pressure steam of 0.1-1.0 MPa calculated | required as a heat source in a factory etc. is obtained. In this embodiment, when an electric drive compressor is used as the external power drive compressor, system electric power for driving the electric drive compressor is required to use the electric drive compressor to convert the suction steam to a medium-pressure discharge steam. However, there is an advantage that medium-pressure discharge steam can be obtained stably.

  In another aspect of the steam generation system using exhaust heat according to the present invention, a primary pressure regulating valve is provided on the steam discharge side of the intermediate pressure steam producing means, and the discharge steam pressure from the intermediate pressure steam producing means is constant. Thus, the operation of the intermediate pressure steam producing means is controlled. Generally, due to fluctuations in the discharge pressure that occurs when the load on the discharge steam usage side changes, the suction ratio (drive steam volume / suction steam volume) of the ejector and compressor that make up the medium-pressure steam production means varies, resulting in system efficiency However, in the steam generation system of the above aspect, the efficiency reduction is effectively prevented, and the system can be operated in a stable state.

  In still another aspect of the steam generation system using exhaust heat according to the present invention, when the pressure in the suction steam supply path to the intermediate pressure steam production means exceeds the set value inside the first steam generation source. In addition, a steam supply stop means or a steam pressure reduction means for stopping the supply of suction steam to the suction steam supply path may be provided, and the suction steam supply path may not include a steam supply stop means. In this aspect, it is possible to omit the steam supply stop means as a safety means normally provided in the suction steam supply path, and the system can be simplified. As the steam pressure reducing means, it is preferable to use exhaust water bypass or discharge of steam from the first steam generation source.

  In another aspect of the steam generation system using exhaust heat according to the present invention, a calculation means for calculating the superheat degree of the discharge steam from the intermediate pressure steam production means, and means for supplying water according to the superheat degree to the discharge steam Can be further provided. In this aspect, when the discharge steam from the intermediate pressure steam production means is superheated steam, the amount of steam can be increased by using the energy of the superheated steam.

  In another aspect of the steam generation system using exhaust heat according to the present invention, when the heat pump includes a brackish water separator, the steam booster can be installed in the brackish water separator. In this aspect, piping connecting the heat pump and the steam booster can be omitted, and pressure loss and temperature drop can be reduced.

  The present invention is further a combined system of a steam generation system using exhaust heat, in which the above-described medium-pressure steam production means is an external power drive compressor, and a cogeneration system having an internal combustion engine as a drive source, A steam generation system is also realized in which the electric power generated by the cogeneration system is used as the driving power of the externally driven compressor, and the exhaust heat of the internal combustion engine is used as the first exhaust heat.

  According to the present invention, it is possible to produce low-pressure steam using exhaust heat emitted from a factory or the like, and further increase the pressure of the low-pressure steam to obtain higher pressure steam. Can be greatly expanded than before, and can contribute to the effective use of exhaust heat.

The figure explaining the 1st aspect of the 1st form of the steam generation system by this invention. The figure explaining the 2nd aspect of the 1st form of the steam generation system by this invention. The figure explaining the 3rd aspect of the 1st form of the steam generation system by this invention. The figure explaining the 4th aspect of the 1st form of the steam generation system by this invention. The figure explaining the 5th aspect of the 1st form of the steam generation system by this invention. The figure explaining the 6th aspect of the 1st form of the steam generation system by this invention. The figure explaining the 7th aspect of the 1st form of the steam generation system by this invention. The figure explaining the 1st aspect of the 2nd form of the steam generation system by this invention. The figure explaining the 2nd aspect of the 2nd form of the steam generation system by this invention. The figure explaining the 3rd form of the steam generation system by this invention. The figure explaining the 4th form of the steam generation system by this invention.

  Hereinafter, some specific examples of a steam generation system using exhaust heat according to the present invention will be described with reference to the drawings.

[First embodiment-part 1]
A steam generation system A1 shown in FIG. 1 uses a hot water heat source heat pump 10 as a first steam generation source B, and an intermediate pressure steam production means C includes a boiler 20 as a second steam generation source and an ejector as a steam booster. 30.

  The hot water heat source heat pump 10 includes, for example, jacket cooling water for an engine cogeneration system, or exhaust water that is steam ring water from steam used in a factory, a hospital, or the like (corresponding to the first exhaust heat in the present invention). Is supplied). Usually, this kind of waste water is 90 degrees C or less. In the hot water heat source heat pump 10, the temperature of the feed water is increased using the exhaust hot water as a heat source, and the hot water heat source heat pump 10 uses the suction steam used in the ejector 30 in the suction steam supply path 12 (first steam in the present invention). Is discharged. Vh1 and Vh2 are flow control valves, and Ph is a pressure gauge on the suction side. The hot water heat source heat pump 10 includes a control panel 11 and controls the opening degree of the flow rate control valves Vh1 and Vh2 according to the value of the pressure gauge Ph. Information exchange is also performed between the control panel 11 and a control panel 31 attached to an ejector 30 described later. Further, the control panel 11 also has a function of shutting off the flow rate control valve Vh1 when the pressure gauge Ph detects that the pressure in the suction steam supply path 12 has exceeded the set value, and the hot water heat source heat pump 10 This prevents the high-pressure drive steam from flowing back from the suction steam supply path 12 to ensure safety.

  The boiler 20 that is the second steam generation source may be a normal boiler that uses city gas or the like as fuel, and includes a control panel 21. Although not shown, an exhaust gas boiler using an exhaust gas such as an industrial furnace as a heat source can also be used. The boiler 20 corresponds to a second heat source in the present invention, and generates a second steam. The second steam passes through the flow control valve Ve1 and is supplied as drive steam to the ejector 30 which is a steam booster. Pe1 is a pressure gauge that measures the pressure of the driving steam. The pressure of the driving steam is higher than the suction steam (first steam) from the hot water heat source heat pump 10.

  As described above, the ejector 30 is supplied with driving steam having a pressure higher than that of the boiler 20, and supplied with suction steam having a pressure lower than that of the hot water heat source heat pump 10 through the suction steam supply path 12. . As a result, the ejector 30 produces steam having a pressure higher than that of the suction steam that is the first steam, and is discharged as discharge steam. The ejector 30 is provided with a control panel 31, and a pressure gauge Pe2 and a flow rate control valve Ve2 are attached to the flow path of the discharge steam, and the medium pressure discharge steam that has passed through the flow rate control valve Ve2 is sent to a consumer side such as a factory. Supplied.

  In general, in an intermediate-pressure discharge steam production system using an ejector, a pressure gauge Pe3 and a flow rate control as shown by a dotted line in FIG. A safety mechanism 13a comprising a valve Ve3 is provided, and when the pressure measured by the pressure gauge Pe3 exceeds a certain pressure, control is performed to determine that the steam is backflowing and close the flow control valve Ve3. In the generation system A1, since the safety mechanism 13 including the pressure gauge Ph and the flow rate control valve Vh1 is incorporated in the hot water heat source heat pump 10, the safety mechanism can be shared, and the pressure gauge Pe3 and the flow rate control valve Ve3 described above can be used. The safety mechanism 13a consisting of can be omitted. Thereby, simplification and cost reduction of the system are possible.

  During operation, pressure signals from the pressure gauges Pe1, Pe2, and Ph are sent to the control panel 31 to control the valve openings of the flow control valves Vh1, Vh2, and Ve1. The boiler 20 is also controlled by exchanging information between the control panel 21 and the control panel 31.

  The steam generation system A1 appropriately controls the valve opening degrees of the flow control valves Vh1, Vh2, Ve1 by the control panels 11, 21, 31 based on the pressure signals of the pressure gauges Pe1, Pe2, Ph. From the medium-pressure steam production means C, a medium-pressure discharge steam of about 0.1 to 1.0 MPa can be obtained.

  Furthermore, the steam generation system A1 can take various control modes for the purpose of stable operation and high efficiency of the system. This is explained below. In the following description, Pe1, Pe2, and Ph refer to pressure values measured by the above-described pressure gauges Pe1, Pe2, and Ph.

  In the first control mode, by controlling the opening degree of the flow rate control valve Ve1 and / or Vh1 with the control panels 31 and 11 according to the values of Pe1, Pe2 and Ph, stable supply of discharged steam is possible. It becomes. That is, when each pressure is determined, the optimum ratio of the suction steam amount and the driving steam amount is automatically determined. Therefore, a signal corresponding to the flow rate ratio is given to the flow control valves Ve1 and / or Vh1, By determining the valve opening degree, it is possible to continuously supply discharge steam having a stable pressure and flow rate.

  In the second control mode, the efficiency of the system can be improved by controlling the pressure of Ph by the flow rate control valve Vh1 according to the values of Pe1 and / or Pe2. That is, as a characteristic of the ejector 30, the minimum pressure that can be naturally sucked is determined by the values of Pe1 and Pe2. On the other hand, since the heat input amount of the heat pump 10 increases as the value of Ph decreases, the heat recovery amount of exhaust heat or exhaust water can be increased by setting the value of Ph as low as possible according to the load. . For example, when the value of Pe2 decreases, the flow control valve Vh1 is moved in the opening direction by the control panel, and the value of Ph is controlled to the minimum necessary pressure.

  In the third control mode, the efficiency of the system is improved by controlling the steam set pressure of the boiler 20 in accordance with the values of Pe1 and / or Pe2. That is, for example, when the value of Ph is a fixed value, the pressure Pe1 of the driving steam necessary to obtain the discharge steam of the desired pressure Pe2 from the ejector 30 is naturally determined. On the other hand, since the efficiency of the boiler 20 itself is improved as the pressure of the driving steam is lower, the fuel consumption of the boiler 20 is reduced by setting the set pressure of the boiler 20 as low as possible according to the load. For example, when the discharge pressure Pe <b> 2 is reduced, the system efficiency is improved by lowering the set pressure of the boiler 20 using the control panel.

  In the fourth control mode, when there is a margin in the supply of driving steam, the heat pump 10 is stopped, and an operating mode in which negative pressure steam is produced and sucked from the exhaust hot water can be taken. As a result, the efficiency of the system can be improved. That is, when the amount of suction steam is smaller than the design value, negative pressure steam is produced without going through a heat pump, so that the efficiency of conversion of waste warm water into steam is increased. In this case, the suction ratio (drive steam amount / suction steam amount) of the ejector 30 increases, but the COP (steam output / energy input amount (primary energy input amount in the case of electric power)) of the heat pump 10 is 1 or less. Since the conversion COP from the exhaust warm water to the negative pressure steam is 1, the conversion efficiency of the exhaust warm water into the steam is improved. For example, when the suction ratio of the ejector 30 is 2 at the design value, the amount of suction steam is small, and when the operation is performed at the suction ratio 5, the negative pressure steam from the hot water is sucked at the suction ratio 4. .

  The fifth control mode is an operation mode in which the flow rate control valve Vh1 is opened after the driving steam starts to flow, and thereby, the backflow of the steam can be prevented, and the safety of the system is improved. For example, by controlling the opening degree of the flow rate control valve Vh1 so that Ph is equal to or higher than the minimum suctionable pressure determined from the operating conditions of the ejector 30, it is possible to prevent high-pressure driving steam from flowing into the heat pump 10 due to the backflow of steam. it can.

  The sixth control mode is a control mode in which the flow rate control valve Vh1 and the flow rate control valve Vh2 are closed to prevent the backflow of steam when the pressure gauge Pe1 or the pressure gauge Pe2 detects abnormal pressure. By quickly detecting the possibility of backflow of the high pressure, it is possible to prevent backflow of high-pressure driving steam to the heat pump 10.

  The seventh control mode is a control mode in which when the Ph rises to a predetermined pressure or more, it is determined that the steam is flowing back, and the flow rate control valve Vh1 and the flow rate control valve Vh2 are closed. In this mode, the heat pump 10 itself performs the back flow. By detecting it, the response at the time of backflow can be accelerated.

  The eighth control mode predicts the load on the discharge steam side from the measured values of the pressure gauges Pe1, Pe2, and Ph and the valve opening trends of the flow control valves Ve1, Ve2, and Vh1, and the heat pump 10 leads the capacity. It is a control mode that performs control (bypass of hot water or cooling water, dilution of solution, control of feed water flow rate, etc.), it is possible to cover the time delay of control by performing capacity control by prediction, and respond to load fluctuations Speeding up. For example, when Pe2 rises, the amount of steam that can be sucked decreases, and the heat input decreases accordingly, and Vh2 moves in the bypass direction. This time delay can be covered by controlling the flow control valve Vh2 according to the value of Pe2.

The above steam generation system using exhaust heat measures each pressure of drive steam, suction steam and discharge steam, calculates the amount of charge reduction and CO ₂ reduction by computer based on it, and monitors the operation status on the display It can also be displayed. Thereby, the effectiveness of the steam generation system can be more clearly appealed.

[First form-part 2]
The steam generation system A2 shown in FIG. 2 is different from the steam generation system A1 shown in FIG. 1 in that the exhaust hot water using exhaust heat from the cogeneration system is used as the exhaust hot water supplied to the hot water heat source heat pump 10. To do. In FIG. 2, reference numeral 40 denotes a drive unit of the cogeneration system, which includes an engine 41 such as a gas engine. Fuel for the engine 41 (for example, city gas) is supplied to the drive unit 40, and electric power is extracted by the operation of the engine 41. The cooling water of the engine 41 is discharged as hot water and supplied to the hot water heat source heat pump 10. Furthermore, in the steam generation system A2, high-temperature exhaust gas (for example, gas engine exhaust gas) from the drive unit 40 is used as a heat source of the above-described boiler 20 (preferably, a boiler that uses engine exhaust gas as a heat source). The

  Other configurations and operation modes such as the ejector 30 are the same as those of the steam generation system A shown in FIG.

  In the steam generation system A2 of this aspect, the exhaust heat from the drive unit 40 of the cogeneration system can be used effectively, which can contribute to the improvement of the overall efficiency of the cogeneration system.

[First embodiment-part 3]
The steam generation system A3 shown in FIG. 3 is the same as that shown in FIG. 1 in that heat is exchanged between the exhaust gas from the boiler or the exhaust gas boiler 20 and the heat source hot water of the hot water heat source heat pump 10 via the heat exchanger 42. It differs from the steam generation system A1 shown. By this heat exchange, the hot water inlet temperature of the hot water heat source heat pump 10 can be improved, and the pressure and / or flow rate of the suction steam is increased accordingly. As a result, it becomes possible to increase the pressure of the discharged steam or decrease the suction ratio. Other configurations and operation modes such as the ejector 30 are the same as those of the steam generation system A shown in FIG.

[First embodiment-part 4]
A steam generation system A4 shown in FIG. 4 is a system in which the steam generation system A2 and the steam generation system A3 are combined.

[First embodiment-part 5]
The steam generation system A5 shown in FIG. 5 is different from the steam generation system A1 shown in FIG. 1 in that the flow control valve Ve2 on the discharge side of the ejector 30 is a primary pressure regulating valve Ve21. In this embodiment, even when the load on the discharge steam side fluctuates, it is possible to maintain the discharge pressure constant by controlling the primary pressure regulating valve Ve21, and the suction ratio of the ejector 30 due to the fluctuation of the discharge pressure. Can be prevented. This will improve the efficiency and stability of the system.

  The other configurations in the steam generation system A5 and the operation modes of the ejector 30 and the like are the same as those in the steam generation system A1 shown in FIG. 1, and the same members are denoted by the same reference numerals and description thereof is omitted.

[First embodiment-part 6]
The steam generation system A6 shown in FIG. 6 is different from the steam generation system A3 shown in FIG. 3 in that a steam drive compressor 30A is used instead of the ejector 30 as a steam booster. Other configurations in the steam generation system A6 are the same as those in the steam generation system A3 shown in FIG. 3, and the same members are denoted by the same reference numerals and description thereof is omitted. Also in this aspect, the steam-driven compressor 30A can produce medium pressure steam as discharge steam in the same manner as the ejector 30. When the amount of heat of the exhaust gas after the heat exchange with the boiler is small, the exhaust gas after the heat exchange with the boiler may be discarded without using the heat exchanger 42.

[First embodiment-part 7]
A steam generation system A7 shown in FIG. 7 is different from the steam generation system A4 shown in FIG. 4 in that a steam drive compressor 30A is used instead of the ejector 30. The other configuration is the same as that of the steam generation system A4 shown in FIG. 4, and the same members are denoted by the same reference numerals and description thereof is omitted. Also in this aspect, the steam-driven compressor 30A can produce medium pressure steam as discharge steam in the same manner as the ejector 30. When the amount of heat of the exhaust gas after the heat exchange with the boiler is small, the exhaust gas after the heat exchange with the boiler may be discarded without using the heat exchanger 42.

[Second embodiment-part 1]
FIG. 8 shows a second embodiment of the steam generation system according to the present invention. In this steam generation system A8, the use of the hot water heat source heat pump 10 as the first steam generation source B is the same as the steam generation system A1 of the first embodiment described above. It differs from the steam generation system A in that the driving compressor 50 is used. Except for the configuration related to the external power drive compressor 50, other configurations and operations are the same as those of the steam generation system A shown in FIG.

  The external power drive compressor 50 includes an external power 52 and a control panel 51, and is driven by the external power 52. As in the case of the steam generation system A, a pressure gauge Pe2 and a flow rate control valve Ve2 are attached to the discharge side of the external power drive compressor 50, and a pressure signal from the pressure gauge Pe2 is sent to the control panel 51. As in the case of the steam generation system A, the flow control valve Ve2 is controlled by the control panel 51, and information is exchanged between the control panel 51 and the control panel 11 provided in the hot water heat source heat pump 10, and the flow rate Control of the control valves Vh1 and Vh2 is performed.

  In this aspect, when an electric drive compressor is used as the external power drive compressor, it is assumed that system power is used, but the entire system has an advantage that the configuration can be simplified. Also in this aspect, the primary pressure regulating valve can be used instead of the flow rate control valve Ve2, as in the case of the steam generation system A5, and the same effect is obtained.

[Second embodiment-part 2]
FIG. 9 shows yet another aspect of the second form of the steam generation system according to the present invention. Here, the steam generation system A8 shown in FIG. 8 is combined with the boiler 20 and the drive unit 40 of the cogeneration system in the steam generation system A4 shown in FIG. 4 to form one system. In this embodiment, an electric drive compressor is used as the external power drive compressor.

  That is, the electric power generated by the cogeneration system is supplied to the external power 52 of the external power drive compressor 50 and used as the drive power of the external power drive compressor 50, and the high temperature exhaust gas from the drive unit 40 of the cogeneration system. Is used as a heat source of the above-described boiler 20 (preferably, a boiler that uses engine exhaust gas as a heat source). Further, in the illustrated example, the exhaust gas after heat exchange with the boiler is supplied to the heat exchanger 42 to exchange heat with the heat source hot water of the hot water heat source heat pump 10. In addition, part or all of the intermediate pressure steam obtained from the boiler 20 is joined to the medium pressure discharge steam produced by the external power drive compressor 50. When the amount of heat of the exhaust gas after the heat exchange with the boiler is small, the exhaust gas after the heat exchange with the boiler may be discarded without using the heat exchanger 42.

  In the steam generation system A9 of this aspect, the electric power produced by the cogeneration system and the exhaust heat from the drive unit 40 of the cogeneration system can be used effectively, and the overall efficiency of the entire system can be improved while using the external power drive compressor 50. Can be improved.

[Third embodiment]
FIG. 10 shows still another modification of the steam generation system according to the present invention. This steam generation system is a mode in which a plurality of the steam generation systems described above are arranged in series and / or in parallel to form one steam generation system A10.

  In the illustrated example, one hot water heat source heat pump 10 is used as the first steam generation source, the boiler 20A and the boiler or the exhaust gas boiler 20B are used as the second steam generation source, and three ejectors are used as the steam boosters. 30A, 30B, and 30C are used. The medium-pressure discharge steam finally discharged is supplied as steam used in a factory or suction steam of an externally driven compressor 60.

  More specifically, the steam generated from the hot water heat source heat pump 10 as the first steam generation source is supplied as suction steam to the first ejector 30A and the second ejector 30B arranged in parallel. The driving steam is combined with the steam from the boiler or the exhaust gas boiler 20B and the steam from the other boiler 20A, and the combined steam is supplied as driving steam to the three ejectors 30A, 30B, and 30C. Is done.

  The discharged steams from the first ejector 30A and the second ejector 30B are combined and supplied as suction steam to the third ejector 30C in the combined state. Then, the final medium-pressure steam is discharged from the third ejector 30C as discharged steam.

  By setting it as such a complex system, the partial load characteristic in the whole system can be improved, and the operating range in the whole system can be expanded.

  In the example shown in FIG. 10, the temperature and pressure of the discharged steam from the third ejector 30C are measured by a measuring device (not shown) to calculate the degree of superheat, and water is sprayed at the ejector outlet according to the degree of superheat. Like to do. By taking such means, the amount of steam can be increased using the energy of superheated steam that is discharged steam, and the efficiency can be further improved. The means for calculating the degree of superheat and supplying water to the discharged steam at the outlet of the ejector according to the degree of superheat can be employed in all the steam generation systems already described.

[Fourth form]
FIG. 11 shows still another modification of the steam generation system according to the present invention. This steam generation system A11 is the structure which has arrange | positioned the ejector 30 in the brackish water separator 15 of a heat pump. In the steam generation system A11, the brackish water separator 15 corresponds to the “first steam generation source for producing the first steam from the first exhaust heat” according to the present invention. In this example, the “medium pressure steam producing means” referred to in the present invention includes a boiler or an exhaust gas boiler 20 and an ejector 30.

  In the steam generation system A11, the wet steam is introduced into the brackish water separator 15 of the heat pump, where it is divided into water and steam. The separated water is sent to a heat pump, and the steam is supplied as suction steam to an ejector 30 located in the brackish water separator 15. On the other hand, the ejector 30 is supplied with the second steam, which is the steam from the boiler or the exhaust gas boiler 20, as the driving steam, so that the steam having a higher pressure than the first steam is discharged from the ejector 30 as the discharged steam. Is done.

  In this embodiment, the piping system such as the suction steam supply path 12 can be eliminated, and the piping resistance of the entire system can be reduced, so that the efficiency of the system can be improved.

A1 to A11: Steam generation system B utilizing waste heat according to the present invention B: First steam generation source,
C: Medium pressure steam production means,
Vh1, Vh2, Ve1, Ve2, Ve3 ... flow control valve,
Ve21 ... primary pressure regulating valve,
Ph, Pe1, Pe2, Pe3 ... Pressure gauge (and its value)
10 ... Hot water heat source heat pump as the first steam generation source,
11 ... Control panel,
12 ... Suction steam supply path,
15 ... Heat pump brackish water separator,
20 ... the boiler which is the second steam generation source,
21 ... Control panel,
30: Ejector that is a steam pressure booster,
30A ... Steam driven compressor,
31 ... Control panel,
40 ... Cogeneration system drive unit,
41 ... an engine such as a gas engine,
42 ... heat exchanger,
50. External power drive compressor as medium pressure steam production means,
51 ... Control panel,
52 ... External power,
60: Externally driven compressor.

Claims (10)

  A first steam generation source for producing first steam from the first exhaust heat; and at least an intermediate pressure steam production means for using the first steam as suction steam; A steam generation system using exhaust heat, characterized in that a discharge steam having a pressure higher than that of the first steam is obtained.   The intermediate pressure steam producing means includes a second steam generation source for producing a second steam having a pressure higher than that of the first steam from a second heat source different from the first exhaust heat, and the second steam. The steam booster uses the first steam as suction steam and uses the second steam as drive steam from the first steam. The steam generation system using exhaust heat according to claim 1, wherein a discharge steam having a high pressure is produced.   The steam generation system using exhaust heat according to claim 2, wherein the steam booster is an ejector.   The steam generation system using exhaust heat according to claim 2, wherein the steam booster is a steam-driven compressor.   The steam generation using exhaust heat according to any one of claims 1 to 4, wherein a discharge steam of 0.1 to 1.0 MPa is obtained as the discharge steam obtained from the intermediate pressure steam production means. system.   The first exhaust heat is the heat of the exhaust hot water from the internal combustion engine, and the second heat source is the heat of the combustion exhaust gas of the same internal combustion engine. A steam generation system using the exhaust heat described in the section.   The steam generation system using exhaust heat according to claim 6, wherein the internal combustion engine is an internal combustion engine as a drive source in a cogeneration system.   It is a steam generation system using the exhaust heat as described in any one of Claims 1-7, Comprising: A primary pressure regulation valve is provided in the steam discharge side of the said intermediate pressure steam production means, The said intermediate pressure steam production means A steam generation system using exhaust heat, wherein the operation of the intermediate pressure steam production means is controlled so that the discharge steam pressure from the tank becomes constant.   It is a steam generation system using the exhaust heat as described in any one of Claims 1-8, Comprising: A said 1st steam generation source is in the inside of the suction steam supply path to the said intermediate pressure steam production means. Provided with a steam supply stopping means or a steam pressure reducing means for stopping the supply of suction steam to the suction steam supply path when the pressure exceeds a set value, and the suction steam supply path does not include a steam supply stop means. A steam generation system using exhaust heat.   A steam generation system using exhaust heat according to any one of claims 1 to 9, wherein a calculation means for calculating the degree of superheat of discharged steam from the intermediate pressure steam production means, and a degree of superheat A steam generation system using exhaust heat, further comprising means for supplying water to discharged steam.

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