JP2019007353A - Binary power generation system - Google Patents

Abstract

To provide a binary power generation system capable of reducing a temperature increase in a heat medium supplied to a binary power generation device when power generation operation of the same is stopped.SOLUTION: A binary power generation system 1 comprises: a heat medium line L1; a heat medium heating device 10; a hot water tank 20 which store water and heats the same through heat exchange between the same and a heat medium; and a binary power generation device 30 which evaporates a working medium through the heat exchange between the working medium and the heat medium and generates power with the evaporated working medium. The hot water tank 20 has a water quantity adjustment mechanism 21 to adjust a water quantity in the hot water tank 20. The water quantity adjustment mechanism 21 adjusts the water quantity in the hot water tank 20 to: a first water quantity while the binary power generation device 30 generates power; and a second water quantity which is larger than the first water quantity while power generation operation of the binary power generation device 30 is stopped.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a binary power generation system.

  The binary power generation system includes an evaporator in which a heat medium heated by heat supply from a heat source evaporates the working medium, and a generator that generates electric power using the steam of the working medium generated by the evaporator. Patent Document 1 discloses a binary power generation device, and this binary power generation device includes a thermal buffer unit that suppresses temperature fluctuations of hot water (heat medium) introduced into the evaporator. The thermal buffer means maintains the heated state of the working medium when the temperature of the heat source is rapidly lowered.

JP 2013-181397 A

  In the binary power generation system, when power generation in the binary power generation device stops, the heat consumption in the binary power generation device decreases rapidly, so it is necessary to stop the heat supply from the heat source or reduce the heat supply amount. There is. However, it may take time to stop the heat supply or reduce the heat supply amount. In that case, the heat supply to the heat medium becomes excessive, the temperature of the heat medium supplied to the binary power generation device excessively rises, and there is a possibility that a problem due to this excessive temperature rise occurs.

  An object of this invention is to provide the binary power generation system which can reduce the temperature rise of the heat medium supplied to a binary power generation device, when the power generation in a binary power generation device stops.

  A binary power generation system according to an aspect of the present invention includes a heat medium line for flowing a heat medium, a heat medium line, a heat medium heating device for heating the heat medium in the heat medium line, and a heat medium. A hot water tank provided with a medium line and disposed downstream of the heat medium heating device, for storing water and heating the water by heat exchange between the water and the heat medium in the heat medium line, and a heat medium line And a binary power generator configured to evaporate the working medium by exchanging heat between the working medium and the heat medium in the heat medium line and generate electric power using the evaporated working medium. The hot water tank has a liquid amount adjusting mechanism for adjusting the amount of water in the hot water tank, and the liquid amount adjusting mechanism adjusts the liquid amount in the hot water tank while the binary power generator generates power. First liquid volume Adjusted to, liquid amount adjusting mechanism, when the binary power generation device stops power generation, adjusted to the second liquid amount of the liquid amount greater than the first amount of liquid in the hot water tank.

  According to this binary power generation system, the hot water tank stores water, and in the hot water tank, the temperature of the water increases and the temperature of the heat medium decreases due to heat exchange between the water and the heat medium in the heat medium line. . The heat medium whose temperature has dropped in the hot water tank is supplied to a binary power generation device disposed downstream of the hot water tank. The liquid volume adjustment mechanism of the hot water tank adjusts the liquid volume in the hot water tank to the first liquid volume while the binary power generator generates power, and when the binary power generator stops generating power, the hot water tank The amount of the liquid is adjusted so as to be a second amount larger than the first amount. When the liquid amount in the hot water tank is the second liquid amount, the temperature of the water in the hot water tank is lower than when the liquid amount is the first liquid amount, and the amount of heat transferred from the heat medium to the water is further increased. Therefore, when the power generation in the binary power generation apparatus is stopped, the temperature increase of the heat medium can be reduced.

  In the binary power generation system according to one aspect of the present invention, when the binary power generation apparatus stops power generation, the binary power generation apparatus generates a signal for adjusting the liquid amount in the hot water tank as the second liquid amount. May be sent to.

  According to this binary power generation system, even if it takes time to stop the heat supply from the heat source or to reduce the heat supply amount, the liquid amount adjusting mechanism can quickly move into the hot water tank based on the signal from the binary power generation device. The amount of water can be the second amount. There is no need for complicated control.

  In the binary power generation system according to one aspect of the present invention, the heat medium line is connected to the upstream side of the heat medium heating device of the heat medium line on the downstream side of the binary power generation device to form a circulation channel. The heat medium may circulate through the heat medium line through the heat medium heating device, the hot water tank, and the binary power generation device.

  According to this binary power generation system, even in the power generation system in which the heat medium circulates through the heat medium heating device, the hot water tank, and the binary power generation device, the amount of water in the hot water tank is set to the second liquid amount. The temperature rise of the medium is reduced.

  ADVANTAGE OF THE INVENTION According to this invention, when the electric power generation in a binary power generation device stops, the binary power generation system which can reduce the temperature rise of the heat medium supplied to a binary power generation device can be provided.

FIG. 1 is a diagram showing a schematic configuration of a binary power generation system according to an embodiment of the present invention. FIG. 2 is a diagram showing an E1 portion of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant descriptions are omitted.

  With reference to FIG. 1, the binary electric power generation system 1 which concerns on one Embodiment is demonstrated. As shown in FIG. 1, the binary power generation system 1 is a system that heats water using a heat medium heated by a heat source 5 such as an exhaust gas boiler, and further generates power. The binary power generation system 1 is disposed on the downstream side of the heat medium heating device 10, the heat medium line L1 for flowing the heat medium, the heat medium heating device 10 for heating the heat medium in the heat medium line L1, The hot water tank 20 for heating the water by heat exchange between the water stored inside and the heat medium in the heat medium line L1, and the heat medium in the working medium and the heat medium line L1 are arranged on the downstream side of the hot water tank 20. A binary power generation apparatus 30 is provided that evaporates the working medium by heat exchange with the medium and generates power using the evaporated working medium. The heat medium line L <b> 1 is provided in the heat medium heating device 10, the hot water tank 20, and the binary power generation device 30. Here, “line” means a pipe through which a fluid flows, and “downstream” is based on the order in which the heat of the heat medium is used.

  As the heat medium flowing through the heat medium line L1, for example, warm water or water vapor can be used. In this case, the exhaust gas boiler of the heat source 5 generates warm water or steam. Note that the heat source 5 of the binary power generation system 1 is not limited to the exhaust gas boiler, and may be, for example, geothermal heat. A fluid other than water may be used as the heat medium, in which case hot water is referred to as a heat medium, and water vapor is referred to as a heat medium vapor. The flow rate of water as the heat medium flowing through the heat medium line L1 is, for example, about 2000 liters per minute.

  A heat medium line L <b> 1 provided in the heat medium heating device 10 includes a heat medium heating line L <b> 10 in the heat medium heating device 10. The heat medium heating line L <b> 10 can heat the heat medium from the heat source 5. This heating is performed by a method such as heat exchange, for example. The binary power generation system 1 is set to stop the heat supply from the heat medium heating device 10 to the heat medium or reduce the heat supply amount when the binary power generation device 30 stops the power generation. Can do.

  The heat medium line L1 includes a water heating heat medium line L20 for heating water stored in the hot water tank 20. In the heat medium line L20 for water heating, heat exchange between the water in the hot water tank 20 and the heat medium flowing through the heat medium line L20 for water heating is performed. The hot water tank 20 has a liquid amount adjusting mechanism 21 for adjusting the amount of water in the hot water tank 20 in two stages. The water in the hot water tank 20 is supplied by the liquid amount adjusting mechanism 21. The liquid amount adjusting mechanism 21 is connected to the makeup water source 7. The temperature of the water in the hot water tank 20 rises by heat exchange between the water in the hot water tank 20 and the heat medium. On the other hand, the temperature of the heat medium decreases. The water in the hot water tank 20 whose temperature has risen is supplied to the hot water usage destination 6 such as hot water supply, snow melting, a heat source of an absorption refrigerator, and the like. The heat medium whose temperature has been lowered flows through the heat medium line L <b> 1 and is supplied to the binary power generation device 30.

  The heat medium line L1 includes a power generation heat medium line L30 for performing binary power generation. The heat medium after heat exchange in the heat medium line L20 for water heating to heat the water in the hot water tank 20 passes through the heat medium line L30 for power generation. The binary power generation device 30 is configured to generate power using a heat medium as a heat source, and can generate power with an output of about 100 kW, for example. The binary power generation device 30 is a device that employs, for example, an organic Rankine Cycle (ORC).

  The binary power generation device 30 includes a working medium line W1 through which a working medium flows. The binary power generator 30 uses an evaporator 31 for exchanging heat between the working medium in the working medium line W1 and the heat medium in the power generation heat medium line L30, and the working medium evaporated in the evaporator 31. A generator 32 for generating electric power and a condenser 33 for condensing the working medium. The generator 32 can generate electric power by rotating the turbine, for example. A working medium line W <b> 1 that is a circulation channel passes through the evaporator 31, the turbine of the generator 32, and the condenser 33. The working medium line W1 may be provided with a working medium circulation pump. A cooling tower 34 is connected to the binary power generation apparatus 30. For example, cooling water cooled by the cooling tower 34 condenses the working medium in the condenser 33. The working medium used for the binary power generator 30 is, for example, an inert gas.

  In the binary power generation system 1, the heat medium line L1 is connected to the upstream side of the heat medium heating device 10 of the heat medium line L1 on the downstream side of the binary power generation device 30 and forms a circulation flow path. The heat medium can circulate through the heat medium heating device 10, the hot water tank 20, and the binary power generation device 30 through the heat medium line L1. Instead of forming a circulation flow path, the heat medium line L1 supplies the heat medium to the outside of the binary power generation system 1 after flowing the heat medium in the order of the heat medium heating device 10, the hot water tank 20, and the binary power generation device 30. May be formed.

  The hot water tank 20 will be described with reference to FIG. FIG. 2 is a view showing the hot water tank 20 and the liquid amount adjusting mechanism 21, and corresponds to the E1 portion of FIG. The liquid amount adjusting mechanism 21 adjusts the liquid amount in the hot water tank 20 to be the first liquid amount while the binary power generation device 30 generates power. When the binary power generation device 30 stops power generation, the liquid amount adjustment mechanism 21 adjusts the liquid amount in the hot water tank 20 to be a second liquid amount that is larger than the first liquid amount. In FIG. 2, a liquid level H1 corresponding to the first liquid amount and a liquid level H2 corresponding to the second liquid amount are shown. The liquid level is defined by the height from the bottom of the hot water tank 20 to the level of the water supplied to the hot water tank 20.

  The liquid amount adjusting mechanism 21 includes, for example, a first water supply unit 22 and a second water supply unit 23. The first water supply unit 22 supplies water into the hot water tank 20 so that the liquid amount in the hot water tank 20 is set to the first liquid amount while the binary power generation device 30 performs power generation. The 1st water supply part 22 has the 1st water supply port 22a containing a ball tap, for example. Water is supplied to the first water supply port 22a from the makeup water source 7 through the first water supply line M22. Water is supplied into the hot water tank 20 through the first water supply port 22a, and the liquid level in the hot water tank 20 becomes the liquid level H1 by the ball tap, that is, the liquid amount in the hot water tank 20 is equal to the first liquid amount. Thus, the liquid level of the hot water tank 20 is controlled. The flow rate of water supplied from the first water supply port 22a to the hot water tank 20 is, for example, 50 liters per minute, and the first liquid amount is, for example, 2 cubic meters.

  The 2nd water supply part 23 has the 2nd water supply port 23a containing a ball tap, for example, and the 2nd valve | bulb 23b provided in the upstream of the 2nd water supply port 23a. Water is supplied to the second water supply port 23a from the makeup water source 7 through the second water supply line M23. The second valve 23b is closed so that water does not pass through the second water supply line M23, for example, by a signal SG supplied from the binary power generator 30 to the second water supply unit 23 while the binary power generator 30 generates power. It can be in the state. Since the second valve 23b is closed while the binary power generation device 30 generates power, water is not supplied to the hot water tank 20 from the second water supply port 23a. On the other hand, water is supplied to the hot water tank 20 from the first water supply port 22a, and the liquid amount in the hot water tank 20 maintains the first liquid amount. The signal SG is, for example, a current that is supplied in response to power generation in the generator 32.

  When the binary power generation device 30 stops power generation, for example, the signal SG supplied from the binary power generation device 30 to the second water supply unit 23 stops, and the second valve 23b passes water through the second water supply line M23. Can be opened. Water is supplied from the second water supply port 23a by the second water supply unit 23 until the liquid amount in the hot water tank 20 reaches the second liquid amount. The second water supply unit 23 is configured so that the liquid level in the hot water tank 20 becomes the liquid level H2, for example, by a ball tap, that is, the liquid amount in the hot water tank 20 becomes the second liquid amount. Control the position. The flow rate of water supplied from the second water supply port 23a to the hot water tank 20 is, for example, 100 liters per minute, and the second liquid amount is, for example, 2.5 cubic meters.

  Transmission of the signal SG from the binary power generation device 30 to the liquid amount adjusting mechanism 21 is performed while the binary power generation device 30 performs power generation, and is stopped when the binary power generation device 30 stops power generation. On the contrary, the transmission of the signal SG may be performed when the binary power generation device 30 is stopped while generating power and the binary power generation device 30 stops generating power. In that case, the opening / closing format of the second valve 23b is opposite to the above. Moreover, the 1st water supply part 22 may have a 1st valve | bulb (not shown) in the upstream of the 1st water supply port 22a in addition to the 1st water supply port 22a containing a ball tap.

  In the binary power generation system 1, the hot water tank 20 stores water, and in the hot water tank 20, the temperature of the water in the hot water tank 20 increases due to heat exchange between the water and the heat medium in the heat medium line L <b> 1. The temperature of the medium decreases. The heat medium whose temperature has dropped in the hot water tank 20 is supplied to the binary power generation apparatus 30 disposed downstream of the hot water tank 20. The liquid amount adjusting mechanism 21 of the hot water tank 20 adjusts the liquid amount in the hot water tank 20 to be the first liquid amount while the binary power generation device 30 generates power, and the binary power generation device 30 stops power generation. Sometimes, the amount of liquid in the hot water tank 20 is adjusted to be a second amount larger than the first amount. When the liquid amount in the hot water tank 20 is the second liquid amount, the temperature of the water in the hot water tank 20 is lower than when the liquid amount is the first liquid amount, and more heat is transferred from the heat medium to the water. Therefore, when the power generation in the binary power generation apparatus 30 is stopped, the temperature increase of the heat medium can be reduced. When the change in the amount of liquid in the hot water tank 20 compensates for a sudden change in the heat demand accompanying the stoppage of power generation of the binary power generation device 30, it takes time to stop the heat supply from the heat medium heating device 10 or decrease the heat supply amount. However, the temperature and pressure of the heat medium are prevented from rising excessively.

  In the present embodiment, when the liquid amount in the hot water tank 20 is the first liquid amount (for example, 2 cubic meters), the temperature of the water in the hot water tank 20 is, for example, 90 degrees Celsius. When the binary power generation device 30 is generating power, the heat medium cooled by the water of 90 degrees Celsius is supplied to the binary power generation device 30. When the binary power generation device 30 stops power generation, the temperature of the heat medium increases, for example, from 95 degrees Celsius to 110 degrees Celsius. As the temperature of the heat medium rises, water is supplied from the second water supply port 23a, so that the liquid amount in the hot water tank 20 becomes the second liquid amount. When the amount of liquid in the hot water tank 20 is the second liquid amount (for example, 2.5 cubic meters), the temperature of the water in the hot water tank 20 decreases to, for example, 78 degrees Celsius. The temperature of the water supplied from the second water supply port 23a to the hot water tank 20 is, for example, 30 degrees Celsius. When the amount of liquid in the hot water tank 20 becomes the second liquid amount, the temperature of the water in the hot water tank 20 decreases from, for example, 90 degrees Celsius to 78 degrees Celsius. As the heat increases, the temperature of the heat medium supplied to the binary power generator 30 falls from 110 degrees Celsius.

  In the binary power generation system 1, even if it takes time to stop the heat supply from the heat medium heating device 10 that heats the heat medium from the heat source 5 or to reduce the heat supply amount, the liquid amount adjusting mechanism 21 is not limited to the binary power generation device. Based on the signal SG from 30, the amount of water in the hot water tank 20 can be quickly made the second amount. When the signal SG supplied from the generator 32 is used, complicated control is not required.

  When the binary power generation device 30 stops power generation, the temperature increase in the heat medium is reduced in the power generation system in which the heat medium circulates through the heat medium heating device 10, the hot water tank 20, and the binary power generation device 30. By setting the amount of water to the second amount, the temperature rise of the heat medium is reduced. In the power generation system in which the heat medium line L1 flows the heat medium in the order of the heat medium heating device 10, the hot water tank 20, and the binary power generation device 30 and then supplies the heat medium to the outside of the binary power generation system 1, the hot water tank By making the liquid amount of the water in 20 the 2nd liquid amount, the temperature rise of a heat carrier is reduced.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to said embodiment. For example, the liquid amount adjustment mechanism 21 may have a structure that causes the water supplied into the hot water tank 20 to overflow instead of a water supply port including a ball tap. That is, when the binary power generation device 30 stops power generation, water is supplied into the hot water tank 20 from the second water supply port 23a, and the water in the hot water tank 20 shows the liquid level H2 corresponding to the second liquid amount. In addition, the water in the hot water tank 20 may overflow.

  For example, the liquid amount adjusting mechanism 21 may have a combination of a liquid level sensor and an electromagnetic valve. That is, a liquid level sensor may be provided in the hot water tank 20, and an electromagnetic valve may be provided in the second water supply port 23a. The liquid level sensor detects the liquid level in the hot water tank 20. When the binary power generation device 30 stops power generation, the solenoid valve is opened, and water is supplied from the second water supply port 23a into the hot water tank 20 until the detection value of the liquid level sensor indicates the liquid level H2 corresponding to the second liquid amount. May be supplied.

  Further, the binary power generation system 1 may include a controller that controls supply / stop of water with respect to the first water supply unit 22 and the second water supply unit 23. For example, the controller may control opening and closing of the second valve 23b based on a signal SG transmitted from the binary power generation device 30 to the second water supply unit 23.

  In the above embodiment, the hot water tank 20 stores water and the water is supplied to the hot water tank 20, but the hot water tank 20 may store seawater and the seawater may be supplied to the hot water tank 20.

DESCRIPTION OF SYMBOLS 1 Binary power generation system 10 Heat medium heating device 20 Hot water tank 21 Liquid quantity adjustment mechanism 30 Binary power generation device L1 Heat medium line

Claims (3)

A heat medium line for flowing the heat medium;
The heat medium line is provided, and a heat medium heating device for heating the heat medium in the heat medium line;
The heat medium line is provided and disposed downstream of the heat medium heating device, and stores water and heats the water by heat exchange between the water and the heat medium in the heat medium line. A hot water tank,
The heat medium line is provided and is disposed downstream of the hot water tank, and the working medium is evaporated by heat exchange between the working medium and the heat medium in the heat medium line. A binary power generation device that generates power;
With
The hot water tank has a liquid amount adjusting mechanism for adjusting the liquid amount of the water in the hot water tank,
The liquid amount adjusting mechanism adjusts the liquid amount in the hot water tank to be the first liquid amount while the binary power generation device generates power,
The liquid amount adjusting mechanism adjusts the liquid amount in the hot water tank to be a second liquid amount larger than the first liquid amount when the binary power generation device stops power generation.   The binary power generation device, when the binary power generation device stops power generation, transmits a signal for setting the liquid amount in the hot water tank to the second liquid amount to the liquid amount adjusting mechanism. Binary power generation system described in The heat medium line is connected to the upstream side of the heat medium heating device of the heat medium line on the downstream side of the binary power generation device to form a circulation channel,
3. The binary power generation system according to claim 1, wherein the heat medium circulates through the heat medium line through the heat medium heating device, the hot water tank, and the binary power generation device.

Images