WO2020045659A1 - Desalination and temperature difference power generation system - Google Patents

Abstract

This desalination and temperature difference power generation system achieves effective usage of temperature difference energy and enhances the performance of the entire system. A plurality of steam motive power cycle units are provided that cause a phase change of a working fluid to obtain motive power for power generation, and an evaporator 11 of one steam motive power cycle unit 10 is supplied with, as a high temperature fluid, steam obtained by evaporating warm seawater with an evaporating means of a seawater desalination device 60, and an evaporator 21 of another steam motive power cycle unit 20 is supplied with, as a high temperature fluid, the residual seawater not evaporated by the evaporating means, and these evaporators respectively evaporate working fluid. Thus, the one steam motive power cycle unit 10 forms a hybrid cycle, the other steam motive power cycle unit 20 forms a closed cycle, and the other steam motive power cycle unit 20: inhibits heat loss on the high temperature fluid side, thereby making it possible to ensure heat that can be effectively used; and additionally, uses residual seawater in a deoxygenation state, thereby making it possible to achieve a state in which biological fouling is unlikely to occur in the evaporator 21.

Description

Desalination and temperature difference power generation system

The present invention relates to an ocean temperature difference power generation system that performs power generation with energy based on the temperature difference between surface seawater and deep seawater, and particularly relates to a steam power cycle unit that obtains power for power generation by circulating a working fluid while changing its phase. The present invention relates to a desalination and temperature difference power generation system in which steam derived from surface seawater is condensed by an evaporator to perform seawater desalination.

海洋 Ocean temperature difference power generation, which generates heat using thermal energy based on the temperature difference between the surface seawater and deep seawater in the ocean, is expected to be put to practical use, and research and development are being promoted in various countries.

海洋 Three types of ocean thermal energy conversion are widely known: open cycle, closed cycle, and hybrid cycle. Of these, the hybrid cycle employs a steam power cycle that uses a low-boiling medium as the working fluid, similar to the closed cycle, to eliminate the need for a special turbine as in the open cycle and to use steam as a high-temperature heat source. As in the case of closed cycle, in the evaporator of the working fluid, the surface seawater as a high-temperature heat source and the evaporator heat transfer surface come into contact with each other, and the heat transfer surface is corroded by biological dirt and seawater. It is not necessary to worry about the generation of seawater, and the water condensed from seawater-derived steam used for heat exchange with the working fluid in the evaporator can be used for drinking and other purposes. Practical application in areas that need to be developed is desired.

Among such ocean temperature difference power generation systems, in particular, a closed cycle type using a steam power cycle using a working fluid has a multi-stage steam power cycle in order to effectively utilize the heat energy of the seawater temperature difference. Conventionally, a method has been proposed in which a fluid serving as a heat source, such as surface warm seawater or deep cold seawater, is used in stages.

This is because each heat source fluid exchanges heat with the working fluid of the steam power cycle having a plurality of stages, and the heat of the heat source fluid is appropriately recovered by the working fluid of each steam power cycle to reduce the loss. The aim is to improve efficiency.
An example of such a conventional ocean temperature difference power generation system using a plurality of stages of steam power cycles is described in JP-A-5-340342.

JP-A-5-340342

The conventional ocean temperature difference power generation system has a configuration as shown in the above-mentioned patent document, and has a plurality of stages of steam power cycles, so that a plurality of stages adapted to temperature changes of hot seawater and cold seawater as heat sources. Can be set as the working fluid of each steam power cycle, and the efficiency of the entire system can be improved.

However, in such a steam power cycle in an ocean temperature difference power generation system using a closed cycle, surface seawater as a high-temperature heat source is introduced into the evaporator to exchange heat with the working fluid, so that biological fouling on the heat transfer surface of the evaporator is performed. It was necessary to take measures against corrosion by seawater and seawater. Conventionally, countermeasures have been taken such as using an expensive material such as titanium which is unlikely to be corroded by seawater on the heat transfer surface of the evaporator, and performing maintenance such as removal of dirt on the heat transfer surface at a constant frequency. However, if the steam power cycle is multi-staged, the cost and maintenance of the evaporator also increase, and from the viewpoint of cost effectiveness, there is a problem that the multi-stage steam power cycle cannot be easily adopted. Was.

On the other hand, in a conventional closed cycle type ocean temperature difference power generation system as disclosed in the above-mentioned patent document, a configuration in which a steam power cycle is provided in a plurality of stages is another system using a working fluid for ocean temperature difference generation, that is, a hybrid. It is also conceivable to apply the present invention to a cycle system so that the thermal energy of the seawater temperature difference can be effectively used.

In an ocean thermal energy conversion system using a hybrid cycle, the evaporator that evaporates the working fluid of the steam power cycle evaporates the working fluid by exchanging heat with the steam that has evaporated seawater and the working fluid, and at the same time condenses the steam. As a result, fresh water is obtained as condensate, which also serves as a condenser for seawater desalination equipment.

In the case of using a multi-stage steam power cycle in such a hybrid cycle system, steam derived from seawater, which is a high-temperature heat source, is heat-exchanged with a working fluid in an evaporator for each of the multiple stages of steam power cycles. Specifically, flash evaporation needs to be performed in a plurality of stages. In this case, the heat loss in the demister or piping through which the steam passes becomes greater than in the case of a single-stage steam power cycle, and the temperature that can be used in the system is higher than in the closed cycle method in which the high-temperature heat source is liquid-phase seawater. Since the energy of the difference becomes small, there is a problem that the merit of providing a plurality of stages of the steam power cycle can hardly be obtained.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and a steam power cycle for temperature difference power generation is provided in a plurality of stages by combining a hybrid cycle system and a closed cycle system, so that it is impossible to effectively use energy of a temperature difference. It is an object of the present invention to provide a desalination and temperature difference power generation system that can be realized without any problems and can enhance the performance of the entire system.

The desalination and temperature difference power generation system according to the present invention heat-exchanges a liquid-phase working fluid with a predetermined high-temperature fluid to evaporate the working fluid, and uses heat energy held by the obtained gas-phase working fluid as power. On the other hand, the process of exchanging the gaseous working fluid after converting the thermal energy into motive power with a predetermined low-temperature fluid to condense, returning the working fluid to the liquid phase, and exchanging heat with the high-temperature fluid again is repeated. A plurality of steam power cycle units to be performed, a power generation device that generates power using power converted from thermal energy in the steam power cycle unit, and one or more evaporation units that evaporate at least a part of seawater, and A seawater desalination apparatus having at least one or a plurality of condensing means for condensing the water evaporated by the evaporating means, and obtaining water containing no salt by condensation in the condensing means; The evaporating means is adapted to perform flash evaporation in which warm seawater on the surface of the ocean is introduced into a predetermined depressurized space reduced in pressure to a pressure lower than the saturated vapor pressure of the seawater to evaporate, and among the steam power cycle units, One steam power cycle unit is supplied with steam evaporated by the evaporation means of the seawater desalination apparatus as the high-temperature fluid, and evaporates the working fluid with heat of condensation when the steam condenses; An evaporator also serving as a condensing means of the device, and a condenser for supplying cold seawater in deep ocean as the low-temperature fluid and condensing a gas-phase working fluid, The steam power cycle section supplies at least a part of the residual seawater that has not evaporated when introduced into the reduced pressure space of the evaporating means in the seawater desalination apparatus as the high-temperature fluid, and Evaporator for evaporating the fluid, and is supplied with cold seawater deep ocean as the cryogenic fluid is made of a condenser for condensing the vapor phase working fluid.

As described above, according to the present invention, a plurality of steam power cycle units that obtain power for power generation by changing the phase of a working fluid by heat exchange with a high-temperature fluid or a low-temperature fluid are provided, and an evaporator in one steam power cycle unit is provided. However, steam obtained by evaporating hot seawater by the evaporating means of the seawater desalination apparatus is supplied as a high-temperature fluid, and the evaporator in another steam power cycle unit is not evaporated by the evaporating means of the seawater desalination apparatus. Seawater is supplied as a high-temperature fluid, and the working fluid is evaporated.At the same time, the condenser in each steam power cycle section is supplied with cold seawater as a low-temperature fluid to condense the working fluid and power is supplied to each steam power cycle section. By doing so, one steam power cycle section forms a hybrid cycle in which the working fluid is evaporated in the evaporator and the steam is condensed, The steam power cycle section of this will form a closed cycle using seawater as a high temperature fluid that exchanges heat with the working fluid in the evaporator, and other steam power cycle sections can effectively use by suppressing heat loss on the high temperature fluid side In addition to securing heat, the residual seawater that has not evaporated by the evaporation means as a high-temperature fluid is exposed to the decompressed space and becomes deoxygenated. The frequency of maintenance for dirt on the heat transfer surface of the evaporator can be reduced, and in the evaporator of one steam power cycle section, steam is circulated to consider corrosion resistance to seawater It is possible to use a material having a general water resistance, for example, a stainless steel material, so that the cost for each steam power cycle unit can be reduced while the steam power cycle can be suppressed. The effective use of energy of a temperature difference due to multiple staged realized without difficulty, enhanced system performance.

In the desalination and temperature difference power generation system according to the present invention, the liquid level position of the liquid-phase working fluid in the working fluid circulation flow path of each steam power cycle unit is set above each evaporator, if necessary. The working fluid in the liquid phase exists in the entire working fluid side flow path in the evaporator, and the heat can be exchanged with the steam or the residual seawater in the evaporator. A gas-liquid separator for separating a gas-phase working fluid and a liquid-phase working fluid is provided on the downstream side.

As described above, according to the present invention, the level of the liquid-phase working fluid to be evaporated in the evaporator of each steam power cycle unit in the working fluid circulation flow path is set above the evaporator, and the entire area of the working fluid side flow path of the evaporator is set. A gas-liquid separator is provided downstream of the evaporator, and the gas-liquid separator separates the gas-phase working fluid from the liquid-phase working fluid. When the working fluid is evaporated by heat exchange with the high-temperature fluid by allowing only the fluid to further proceed in the working fluid circulation flow path, the generated gas-phase working fluid travels upward as bubbles while the liquid that has not evaporated The gas phase working fluid flows to the outlet side of the flow path together with the phase working fluid and flows out of the evaporator. The gas phase working fluid that has not accumulated in the It is possible to reliably prevent the heat exchange between the liquid-phase working fluid and the high-temperature fluid and prevent the working fluid from evaporating smoothly by preventing the contact with the heat transfer surface. Can be evaporated.

In addition, the desalination and temperature difference power generation system according to the present invention may convert the liquid-phase working fluid separated by the gas-liquid separator in the one steam power cycle unit into a vapor in another steam power cycle unit as necessary. The liquid-phase working fluid separated by the gas-liquid separator in the other steam power cycle section is caused to flow into a predetermined position of the working fluid flow path from the liquid separator or evaporator to the gas-liquid separator, The pressurized gas flows into a predetermined portion of the evaporator or the liquid-phase working fluid flow path upstream of the evaporator in the power cycle unit, if necessary.

As described above, according to the present invention, the liquid-phase working fluid separated by the gas-liquid separator of one steam power cycle unit is transferred from the gas-liquid separator or evaporator to the gas-liquid separator in another steam power cycle unit. As the liquid-phase working fluid flows into the low-pressure flow path and evaporates partially, the gas-phase working fluid is increased by the gas-liquid separator. On the other hand, the working fluid in the liquid phase separated by the gas-liquid separator of the other steam power cycle unit is supplied to the evaporator or the liquid-phase working fluid flow path upstream of the evaporator in the one steam power cycle unit. By increasing the power obtained by the work of the gas-phase working fluid in the other steam power cycle unit while maintaining the power obtained in one steam power cycle unit, the power generation output is increased by flowing back into a predetermined location. The temperature difference can be It can be further effective use ghee.

In addition, the desalination and temperature difference power generation system according to the present invention includes a decompression vessel for flowing seawater into an internal decompression space before being evaporated by the seawater desalination apparatus, if necessary. A discharge tank for temporarily storing seawater into which gas components have been separated by inflow, and which allows foreign substances in the seawater to flow into the water near the surface of the seawater at the center of the storage tank and discharge the water to the outside of the container. A part is provided, and a vortex is generated in the seawater stored in the storage tank with the center of the storage tank as a center of flow, and the floating foreign matter in the seawater is collected in the center of the storage tank, and the collected foreign matter is discharged from the discharge unit. To discharge.

As described above, according to the present invention, seawater before being evaporated by the seawater desalination apparatus is temporarily stored in the decompression vessel, and a vortex is generated in the stored seawater, so that the floating property of the seawater is improved. By collecting the foreign matter at the center of the vortex and discharging the foreign matter to the outside of the container through the discharge unit provided corresponding to the place where the foreign matter gathers, even if the amount of seawater to be treated becomes large, The contaminants can be separated appropriately and continuously, so that the seawater desalination equipment is not adversely affected by the contaminants, and clogging is eliminated as in the case of using a general screen for removing contaminants. It is not necessary to perform maintenance of the system frequently, and it is possible to efficiently remove foreign matter and use seawater, and to obtain the energy of the temperature difference from the seawater without difficulty to operate the system.

FIG. 1 is a schematic explanatory diagram of a desalination and ocean temperature difference power generation system according to a first embodiment of the present invention. It is a front view of the evaporator in one steam power cycle part used in the desalination and ocean temperature difference power generation systems concerning a 1st embodiment of the present invention. It is a schematic structure explanatory view of the evaporator heat exchange part in one steam power cycle part used in the desalination and ocean temperature difference power generation systems concerning the first embodiment of the present invention. It is a longitudinal section of the evaporator in one steam power cycle part used in the desalination and ocean temperature difference power generation systems concerning a 1st embodiment of the present invention. FIG. 2 is a schematic front view of an evaporator in another steam power cycle unit used in the desalination and ocean temperature difference power generation system according to the first embodiment of the present invention. It is a schematic structure explanatory view of the evaporator heat exchange part in the other steam power cycle part used in the desalination and ocean temperature difference power generation systems concerning the first embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view and a vertical cross-sectional view of a deaerator used in a desalination and ocean temperature difference power generation system according to a first embodiment of the present invention. It is a schematic explanatory view of a desalination and ocean temperature difference power generation system concerning a second embodiment of the present invention. It is a front view of another evaporator in one steam power cycle part used for the desalination and ocean temperature difference power generation systems concerning a 2nd embodiment of the present invention. It is a longitudinal section of the evaporator in one steam power cycle part used in the desalination and ocean temperature difference power generation systems concerning a 3rd embodiment of the present invention. It is a front view of the evaporator in one steam power cycle part used for the desalination and ocean temperature difference power generation systems concerning a 4th embodiment of the present invention. It is a schematic perspective view of the heat exchange part and the non-condensable gas collection part in the evaporator of one steam power cycle part used in the desalination and ocean temperature difference power generation systems concerning a 4th embodiment of the present invention. FIG. 13 is a schematic perspective view of another heat exchange section and an uncondensable gas collection section in an evaporator of one steam power cycle section used in a desalination and ocean temperature difference power generation system according to a fourth embodiment of the present invention. It is a schematic front view of the heat exchange part and the non-condensable gas collection part in the evaporator of one steam power cycle part used in the desalination and ocean temperature difference power generation systems concerning the fifth embodiment of the present invention. It is a partially cutaway perspective view of an uncondensable gas collection part in an evaporator of one steam power cycle part used in a desalination and ocean temperature difference power generation system according to a fifth embodiment of the present invention. It is an explanatory view of the attachment state to the plate for heat exchange of the non-condensable gas collection part in the evaporator of one steam power cycle part used for the desalination and ocean temperature difference power generation systems concerning a 5th embodiment of the present invention.

(First embodiment of the present invention)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
In each of the drawings, the desalination and temperature difference power generation system 1 according to the present embodiment includes two steam power cycle units 10 and 20 for converting heat energy obtained from a working fluid into power, and heat energy in each steam power cycle unit. Power generation devices 51 and 52 that generate power using the power converted from the water, a seawater desalination device 60 that condenses water vapor evaporated from seawater to obtain fresh water, and a seawater desalination device 60 that is disposed in front of the seawater desalination device 60; And a deaerator 70 for separating and removing dissolved gas components from seawater.

The steam power cycle units 10 and 20 exchange heat with a high-temperature fluid and a working fluid composed of a low-boiling medium such as, for example, ammonia, and evaporate the working fluid to obtain vapor-phase working fluids. The turbines 12 and 22 operate by introducing a gas-phase working fluid and convert thermal energy possessed by the working fluid into motive power, and heat-exchange the gas-phase working fluid exiting the turbines 12 and 22 with a low-temperature fluid. The condensers 13 and 23 are condensed to be in a liquid phase, and pumps 14 and 24 for sending the liquid-phase working fluid extracted from the condensers 13 and 23 to the evaporators 11 and 21. Among them, the turbines 12 and 22, the condensers 13 and 23, and the pumps 14 and 24 are known devices similar to those used in a general steam power cycle, and the description thereof is omitted.

The flow paths of the working fluid in the steam power cycle units 10 and 20 are independent of each other, and convert the heat energy obtained from each working fluid into power for each steam power cycle unit 10 and 20. It will be.

Among the steam power cycle units 10 and 20, one steam power cycle unit 10 supplies the steam derived from the surface seawater generated by the seawater desalination apparatus 60 to the evaporator 11 as the high-temperature fluid, and Seawater is supplied to the condenser 13 as the low-temperature fluid.

On the other hand, the other steam power cycle section 20 supplies the residual seawater not evaporated in the seawater desalination device 60 to the evaporator 21 as the high-temperature fluid, and supplies the deep seawater to the condenser 23 as the low-temperature fluid. The Rukoto.

Of these, the deep seawater as the low-temperature fluid passes through the condenser 23 of the second steam power cycle unit 20 and then goes to the condenser 13 of the first steam power cycle unit 10 so that the deep seawater flows in this order. , 23 are interconnected in series, so that the steam power cycle units 10 and 20 commonly use the deep seawater.

The evaporator 11 of one steam power cycle unit 10 is formed by integrating a plurality of heat exchange plates 15 made of a plurality of substantially rectangular thin metal plates in a parallel state. Having a heat exchange portion 11a for exchanging heat with the air, and a hollow container-like shell 11b having an internal space separated from the outside by a partition wall and arranged to accommodate the heat exchange portion 11a in the internal space. It is.

The heat exchange section 11a is disposed in the inner space of the shell 11b, and exchanges heat between steam as a high-temperature fluid flowing from the outside and a working fluid in a liquid phase to condense the steam to obtain a condensed liquid. A vapor-phase working fluid is obtained by evaporating at least a part of a phase working fluid.

The heat exchanging part 11a is provided in such a manner that each of the plurality of heat exchange plates 15 made of a substantially rectangular metal thin plate is arranged in a water-tight state with one heat exchange plate adjacent at two predetermined two substantially parallel end portions. On the other hand, the other heat exchange plates adjacent to each other and the other substantially parallel two end sides substantially orthogonal to the two end sides are welded in a watertight state, and all are integrally formed. (See FIG. 3).

The heat exchanging part 11a has one first flow path 15b through which the steam and the condensate condensed by the water vapor pass, and one second flow path 15c through which the working fluid passes between the heat exchange plates 15. The opening of the first flow passage 15b, which is generated every other time and through which steam and condensate can flow in and out, and the opening of the second flow passage 15c through which the working fluid flows in and out, form a right angle. Configuration. That is, the heat exchange section 11a adopts a so-called cross-flow heat exchanger structure in which the steam flowing through each of the first flow paths 15b and the working fluid flowing through each of the second flow paths 15c form a cross flow. .

In addition, the heat exchange unit 11a tilts the entire heat exchange unit into the inner space of the shell 11b such that the opening on the working fluid outflow side of the second flow path 15c is above the opening on the working fluid inflow side. Is arranged.

The arrangement of the heat exchange unit 11a at an angle is not limited to a mode in which the heat exchange unit 11a is attached to the shell 11b in an inclined state (see FIG. 2). The inclined shell may be installed at an angle to obtain a state in which the heat exchange unit integrated with the shell is inclined.

The shell 11b is formed in a hollow container shape having an internal space isolated from the outside, is capable of introducing water vapor from the outside to the internal space, and capable of taking out condensate from the internal space to the outside, and penetrates the partition. This is a configuration in which a working fluid inflow / outflow channel is provided.

A heat exchange portion 11a, which is tilted and accommodated in the shell 11b, connects the inflow / outflow passage of the working fluid to the opening of the second passage 15c, and also connects to the opening other than the opening of the second passage 15c. A working fluid that is arranged so as to interpose a predetermined gap between the inner surface of the shell partition wall and the opening of the first flow path 15b so as to face up and down, and flows into each second flow path 15c through the inflow / outflow flow path; Heat is exchanged with the steam flowing into each first flow path 15b from the shell internal space.

In addition, in the internal space of the shell 11b, in response to the condensed liquid flowing down from the heat exchange part 11a which is disposed at an angle, a water recovery part 11c for receiving the condensed liquid is provided near the side surface of the shell 11b. Provided.

On the outside of the shell 11b, a pipe 11d serving as a working fluid circulation flow path of a steam power cycle, for allowing a working fluid to flow into and out of each of the second flow paths 15c of the heat exchange section 11a through the inflow / outflow flow path. It is a configuration to be connected. Further, outside the shell 11b, a storage unit 40 for collecting the condensed liquid that flows down from the heat exchange unit 11a, reaches the inner space of the shell 11b, and is finally discharged outside the shell is connected.

The evaporator 21 of the other steam power cycle unit 20 is formed by integrating a plurality of heat exchange plates 15 made of a plurality of substantially rectangular thin metal plates in a parallel state, and heats a high-temperature fluid and a working fluid flowing from the outside. It has a heat exchange part 21a to be exchanged, and a hollow container-like shell 21b having an internal space isolated from the outside by a partition wall and arranged to accommodate the heat exchange part 21a in this internal space.

The heat exchanging part 21a is disposed in the inner space of the shell 21b and exchanges heat between the residual seawater as a high-temperature fluid flowing from the outside and the working fluid in the liquid phase, and evaporates at least a part of the working fluid in the liquid phase. Thus, a gas-phase working fluid is obtained.

The heat exchanging part 21a is arranged such that a plurality of heat exchanging plates 15 made of a substantially rectangular thin metal plate are arranged in a watertight state with one heat exchanging plate adjacent thereto at two predetermined substantially parallel end portions. On the other hand, the other heat exchange plates adjacent to each other and the other substantially parallel two end sides substantially orthogonal to the two end sides are welded in a watertight state, and all are integrally formed. (See FIG. 6).

The heat exchange section 21a generates alternate first flow paths 15d through which the working fluid passes and second alternate flow paths 15e through which the residual seawater passes, between the heat exchange plates 15, respectively. The opening of the first flow passage 15d through which the fluid can flow in and out and the opening of the second flow passage 15e through which the residual seawater can flow in and out are arranged at right angles. That is, the heat exchange unit 21a adopts a so-called cross-flow heat exchanger structure in which the working fluid passing through each of the first flow paths 15d and the residual seawater passing through each of the second flow paths 15e form a cross flow. Become.

The shell 21b is formed in the shape of a hollow container having an internal space isolated from the outside, and has a configuration in which a working fluid and a residual seawater inflow / outflow channel penetrating a partition wall are provided.
The heat exchange part 21a accommodated in the shell 21b connects the flow path for inflow and outflow of the working fluid and the opening of the first flow path 15d, and the flow path for inflow and outflow of residual seawater and the second flow path 15e. Are arranged so that the opening of the first flow path 15d faces up and down. The liquid-phase working fluid that has flowed in from the lower opening portion of each first flow path 15d is heat-exchanged with the residual seawater flowing through each second flow path 15e to evaporate, and the generated gas-phase working fluid is discharged to each first flow path. It is a mechanism to take out from the upper opening of 15d.

The outside of the shell 21b is connected to a pipe 21c that forms a working fluid circulation flow path of a steam power cycle that allows the working fluid to flow into and out of the first flow paths 15d of the heat exchange section 21a through the inflow / outflow flow path. At the same time, a configuration is adopted in which a pipe 21d through which the residual seawater flows in and out through the inflow / outflow channel is connected to each of the second flow channels 15e of the heat exchange section 21a.

The power generators 51 and 52 generate electric power by using power converted from thermal energy in each steam power cycle unit. Specifically, the power generators 51 and 52 are driven by the turbines 12 and 22 to generate electric power. These power generators 51 and 52 are the same as those used for power generation using a known turbine as a drive source, and a detailed description thereof will be omitted.
The steam power cycle units 10 and 20 and the power generators 51 and 52 constitute a temperature difference power generation system that generates power using a plurality of steam power cycles.

The seawater desalination apparatus 60 has an evaporating means for evaporating at least a part of the seawater, and one or more condensing means for condensing the water evaporated by the evaporating means. It is to obtain fresh water that does not contain.

Among them, the evaporating means is an evaporating unit 61 for performing flash evaporation in which the surface seawater is introduced into a predetermined evaporation space reduced in pressure to a pressure lower than the saturated vapor pressure of the seawater and evaporated.
The evaporating section 61 has therein an evaporating space which communicates with the evaporator 11 of one steam power cycle section 10 and has a hollow depressurized container 61a in which the evaporating space is in a depressurized state lower than the atmospheric pressure. An injection unit 61b disposed in the decompression container 61a and injecting seawater introduced from the outside into the evaporation space of the decompression container 61a in a mist, water droplet, water film, water column, or the like. In this configuration, the seawater injected from the injection unit 61b is flash-evaporated in the evaporation space in the decompression container 61a to obtain water vapor.

(4) The decompression vessel 61a of the evaporator 61 communicates with the shell 11b of the evaporator 11 of the one steam power cycle unit 10, so that the steam generated in the evaporator 61 can be introduced into the inner space of the shell 11b.

Further, a decompression exhaust device 64 is connected to the decompression container 61a of the evaporator 61 through a pipe line, a shell 11b of the evaporator 11, or the like, and the evaporation space in the decompression container 61a is connected to the shell 11b of the evaporator 11 communicating therewith. At the same time, the pressure is adjusted to a pressure lower than the saturated vapor pressure of water at the same temperature as the seawater to be evaporated in the decompression vessel 61a, and the water in the seawater changes from a liquid phase to a gas phase in the decompression vessel 61a (evaporates). ) The temperature and the temperature at which the vapor changes from the gas phase to the liquid phase (condenses) in the heat exchange section 11a in the shell 11b are maintained lower than the respective temperatures at atmospheric pressure.
As a result, a part of the seawater introduced into the depressurized container 61a changes from a liquid phase to a gas phase, and the temperature of the seawater remaining in the liquid phase decreases.

The seawater introduced into the evaporator 61 and evaporated is, for example, warm seawater on the surface of the ocean. The seawater withdrawn from the sea is once guided to the deaerator 70 to remove the air in the seawater, and then guided to the evaporator 61. To be.

The evaporator 11 of the first steam power cycle unit 10 in which the water vapor evaporated in the evaporator 61 is supplied as the high-temperature fluid, exchanges heat between the water vapor and the working fluid, and evaporates the working fluid. It condenses steam, and also serves as a condensing means of the seawater desalination apparatus 60.

Then, a part of the residual seawater that has not been evaporated even when introduced into the decompression vessel 61a of the evaporator 61 in the seawater desalination apparatus 60 is supplied as a high-temperature fluid to the evaporator 21 of the other steam power cycle unit 20. This is a mechanism for evaporating the working fluid by heat exchange.

The deaerator 70 is disposed in front of the evaporator 61 of the seawater desalination apparatus 60 so as to be able to supply seawater to the evaporator 61, and allows seawater to flow into a decompression space in a decompression vessel and to be dissolved in seawater. It separates and removes gaseous components from seawater.

The lower part of the decompression space of the deaerator 70 serves as a storage tank 72 for temporarily storing seawater into which gas components have been separated from a plurality of seawater jets 71. A discharge unit 73 is provided to allow foreign substances in the seawater to flow into the water near the seawater surface at the center of the storage tank 72 and to be discharged to the outside of the deaerator.

In the deaerator 70, a vortex is generated in the seawater accumulated in the storage tank 72 around the center of the storage tank, and the floating foreign matter in the seawater is collected in the center of the storage tank, and the collected foreign matter is discharged. It will be discharged from the unit 73.

In addition, regarding the discharge of foreign matter using a mechanism such as the discharge unit 73 in the deaerator 70, any device other than the deaerator can be used as long as it is a device that can temporarily store seawater containing foreign matter in a decompression container. For example, the same mechanism as described above may be adopted and executed in a decompression container of a flash evaporator.

Next, an operation state of the desalination and ocean temperature difference power generation system based on the above configuration will be described. As a premise, while continuously generating steam in the seawater desalination device 60, in each steam power cycle unit 10, 20, steam or residual seawater as a high-temperature fluid is supplied to the evaporators 11, 21 and as a low-temperature fluid. Is introduced into the condensers 13 and 23 at a flow rate sufficient to perform heat exchange, respectively, so that the evaporators 11 and 21 and the condensers 13 and 23 can continue the heat exchange under the same conditions. There is.

First, the surface seawater taken from the sea is introduced into the deaerator 70, and the seawater flows into the decompression space of the deaerator 70 to separate and remove gas components dissolved in the seawater from the seawater.
At this time, in the storage tank 72 at the lower part of the decompression space of the deaerator 70, the seawater that has flowed into the decompression space from the plurality of seawater jets 71 and separated into gas components is temporarily stored, and is stored in the storage tank 72. In the seawater, a vortex flow with the center of the storage tank as the center of flow is generated. Under the influence of this vortex flow, floating foreign matters in the seawater collect at the center of the storage tank, and the collected foreign matters are discharged to the discharge section 73 provided at the center of the storage tank 72 so as to have an opening near the seawater surface. Is discharged to the outside of the deaerator.

In the deaerator 70, the foreign matter can be removed from the seawater through the discharge part 73 at the center of the storage tank 72, so that the foreign matter mixed in the seawater can be appropriately and continuously separated even when the amount of the seawater to be treated increases. In addition, it is possible to prevent foreign substances from adversely affecting the seawater desalination equipment on the downstream side, and it is necessary to perform maintenance such as removal of clogging with high frequency as in the case of using a general screen for removing foreign substances Therefore, seawater can be supplied to the evaporation step by removing foreign matters efficiently.
The seawater from which gas components and foreign substances have been removed by the deaerator 70 is introduced into the seawater desalination device 60.

In the seawater desalination device 60, the seawater that has exited the deaerator 70 is guided into the depressurized container 61a of the evaporator 61, and in the depressurized container 61a of the evaporator 61, is sprayed or sprayed from the injection unit 61b. It is injected into the evaporation space in the decompression container 61a. Most of the water in the seawater changes into gaseous water containing no impurities, ie, water vapor, by flash evaporation in the pressure reducing vessel 61a whose pressure is reduced to about 10 to 60 mmHg, and at the same time, the temperature of the seawater drops I do.
The water vapor obtained by evaporation of the water travels in the decompression vessel 61a together with the surrounding gas, and reaches the evaporator 11 of one steam power cycle unit 10 in a state separated from the liquid (mist).

In the evaporator 11, the steam enters the internal space from the opening at the top of the shell 11b. Then, the steam proceeds through the internal space of the shell 11b and flows in from the upper and lower openings in the first flow path 15b of the heat exchange unit 11a. That is, the steam flows from the internal space of the shell 11b into the first flow path 15b from the upper opening of the first flow path 15b in the heat exchange section 11a, and travels downward through the first flow path 15b. And heat exchange with the working fluid via the heat exchanger, condenses on the surface of the heat exchange plate 15 facing the first flow path 15b, and becomes liquid water. In addition, the steam travels downward in the internal space of the shell 11b, passes beside the heat exchanging unit 11a, reaches below the heat exchanging unit 11a, and turns upward to be below the first flow path 15b in the heat exchanging unit 11a. Also flows into the first flow path 15b from the opening portion on the side of the first flow path, and heat-exchanges with the working fluid via the heat exchange plate 15 while traveling upward through the first flow path 15b, so that the heat exchange flow faces the first flow path 15b. It condenses on the surface of the plate 15 and becomes liquid water.

In this way, while the steam flowing into the first flow path 15b from the upper and lower openings condenses by exchanging heat with the working fluid via the heat exchange plate 15 while traveling inside the heat exchange section 11a, particularly the lower opening Can quickly come into contact with the lower part of the heat exchange plate 15, the heat exchange accompanying the contact of the water vapor with each part of the heat exchange plate 15 proceeds smoothly, and uncondensed water flowing toward the inside of the heat exchanger Is sequentially condensed.

The water condensed on the surface of the heat exchange plate 15 flows down to the lower opening portion of the first flow path 15b in the heat exchange section 11a, but the heat exchange section 11a is disposed obliquely. The water condensed in the one flow path 15b flows on the surface of the heat exchange plate 15 toward the inflow-side opening of the second flow path 15c in the lower heat exchange section 11a, and gathers there. From the lowermost portion of the lower opening portion to the outside of the heat exchange portion 11a.

Thereby, when the water recovery part 11c which receives the water condensed in the internal space of the shell 11b and guides it to the outside is provided, a part of the water recovery part 11c in which the condensed liquid can flow down in the lower opening portion of the first flow path 15b. The heat exchanger can be reduced to a size corresponding to the range, and the heat exchanger can be made compact.
The water flowing down from the heat exchange unit 11a goes out of the shell 11b, is collected in the storage unit 40, and is sent to the outside as a mass of water.

In addition, the seawater that has not evaporated in the evaporator 61 of the seawater desalination apparatus 60 temporarily accumulates in the lower part of the decompression vessel 61a as residual seawater, but most of the seawater is taken out of the decompression vessel 61a, Is supplied to the evaporator 21 of the steam power cycle section 20.

This residual seawater is in a deoxygenated state where most of the oxygen dissolved in the original seawater has been removed by being injected into the decompressed evaporation space, and microorganisms are present in the seawater. But they can be inactivated.

On the other hand, in each of the steam power cycle units 10 and 20, heat exchange is performed between the high-temperature fluid and the liquid-phase working fluid in the evaporators 11 and 21, and the working fluid is heated and evaporated to obtain a gas-phase working fluid. . This gas-phase working fluid goes out of the evaporators 11 and 21 and goes to the turbines 12 and 22.

When the gas-phase working fluid reaches the turbines 12 and 22, it expands and operates these turbines 12 and 22. The power generators 51 and 52 are driven by the turbines 12 and 22, respectively, and the heat energy is used as usable energy. Is converted to electric power.
The gas-phase working fluid expanded and worked in the turbines 12 and 22 is reduced in pressure and temperature, exits the turbines 12 and 22, and is introduced into the condensers 13 and 23.

In the condensers 13 and 23, the introduced gas-phase working fluid exchanges heat with deep seawater as a low-temperature fluid, is cooled and condensed, and changes to a liquid phase.
The liquid-phase working fluid obtained by the condensation exits the condensers 13 and 23, is pressurized via the pumps 14 and 24, and then proceeds to the evaporators 11 and 21.
Thereafter, the working fluid in the liquid phase returns to the inside of the evaporators 11 and 21 via the working fluid flow path, and the respective steps after the heat exchange in the evaporators 11 and 21 are repeated as described above.

Of the series of phase changes of the working fluid in the steam power cycle units 10 and 20, the evaporation of the working fluid in the evaporators 11 and 21 will be specifically described.
In the evaporator 11 of the one steam power cycle unit 10, the liquid-phase working fluid passes through the inlet / outlet passage of the shell 11b from the conduit 11d forming the working fluid passage, and the second passages 15c of the heat exchange unit 11a. Flows into. This liquid-phase working fluid exchanges heat with the steam as a high-temperature fluid flowing through the first flow path 15b in the heat exchange section 11a via the heat exchange plate 15, and a part thereof evaporates.

When the working fluid evaporates in the second flow path 15c, the gas-phase working fluid that is generated as air bubbles tends to move upward in the liquid-phase working fluid. As it goes to the upper part of the flow path 15c, it goes to the opening part on the outflow side of the second flow path 15c located on the upper side.

As described above, since the heat exchange unit 11a is disposed so as to be inclined such that the opening portion on the working fluid outflow side in the second flow path 15c is located at the upper portion, the vapor-phase working fluid is discharged as the evaporation proceeds. Even if the state of ascending the flow path 15c continues, the gas-phase working fluid can escape from the upper part of the opening of the second flow path 15c to the outside of the second flow path 15c, and There is no stay at the top of the.

For this reason, when the working fluid in the liquid phase evaporates by heat exchange, as in the case where the conventional evaporator is simply provided with the working fluid flow path in the horizontal direction, the vaporized working fluid in the vaporized state flows out of the flow path. The gaseous working fluid stays at the top of the flow path without exiting, and the accumulated gas-phase working fluid prevents contact between the liquid-phase working fluid and the surface of the heat exchange plate, thereby reducing the efficiency of heat exchange between the working fluid and steam. Can be prevented.

In this way, when the working fluid in the liquid phase exchanges heat with the steam in the evaporator 11 and the working fluid is heated and evaporated, the working fluid that has evaporated to the gas phase exits the evaporator 11 and goes to the turbine 12. It will be.

Further, in the evaporator 21 of the other steam power cycle section 20, the liquid-phase working fluid flows from the pipe 21c forming the working fluid flow path to the first flow path of the heat exchange section 21a through the inflow / outflow flow path of the shell 21b. 15d. At the same time, the remaining seawater that has not evaporated in the evaporator 61 flows into each of the second channels 15e of the heat exchange unit 21a from the pipe 21d through the inflow / outflow channels of the shell 21b.
As a result, the liquid-phase working fluid in the first flow path 15d exchanges heat with the residual seawater as a high-temperature fluid flowing through the second flow path 15e via the heat exchange plate 15, and a part of the working fluid evaporates.

While evaporating the working fluid by heat exchange in the heat exchange unit 21a, the surface of the heat exchange plate 15 facing the second flow path 15e comes into contact with residual seawater flowing through the second flow path 15e. Is in a deoxygenated state and inactivates microorganisms in the seawater. Therefore, it is difficult for biological stains to adhere to the heat exchange plate 15 without frequently performing maintenance such as soil removal. The maintenance cost of the evaporator 21 can be reduced.

When the working fluid evaporates in the first flow path 15d, the gas-phase working fluid generated as air bubbles rises directly in the first flow path 15d, which is vertically continuous with the heat exchange unit 21a, due to the property of moving upward. Reaches the upper opening of the first flow path 15d, and flows out of the first flow path 15d from this opening.

In this way, the working fluid in the liquid phase is subjected to heat exchange with the residual seawater in the evaporator 21, and the working fluid is heated and evaporated. I will head.

に 対 し In contrast to the working fluid, the residual seawater used for heat exchange in the evaporator 21 lowers its temperature by transferring heat to the working fluid. After the residual seawater is discharged out of the evaporator 21, it is finally discharged into the sea outside the system.

As described above, in the desalination and ocean temperature difference power generation system according to the present embodiment, the steam power cycle unit 10 that obtains power for power generation by changing the phase of the working fluid by heat exchange with a high-temperature fluid or a low-temperature fluid, The steam evaporator 11 in one steam power cycle unit 10 is supplied with steam obtained by evaporating the surface seawater in the evaporator 61 of the seawater desalination apparatus 60 as a high-temperature fluid, and the other steam power cycle unit The evaporator 21 in 20 supplies the residual seawater that has not evaporated in the evaporator 61 of the seawater desalination apparatus 60 as a high-temperature fluid, evaporates the working fluid, and also condenses the condenser 13 in each of the steam power cycle units 10 and 20. , 23 are supplied with deep seawater as a low temperature fluid to condense the working fluid and generate power for power generation in each steam power cycle unit 10, 20. Therefore, one steam power cycle unit 10 forms a hybrid cycle in which the working fluid is evaporated in the evaporator 11 and water vapor is condensed, while the other steam power cycle unit 20 exchanges heat with the working fluid in the evaporator 21. A closed cycle using seawater as the high-temperature fluid to be performed is performed. In the other steam power cycle unit 20, heat loss on the high-temperature fluid side can be suppressed to ensure effective use of heat. Is exposed to the decompression space to be in a deoxygenated state, and the microorganisms in the seawater are in an inactive state, so that biological contamination is unlikely to occur, and maintenance for the contamination on the heat transfer surface of the evaporator 21 is performed. The frequency can be reduced, and in the evaporator 11 of the one steam power cycle unit 10, the steam is circulated so that the corrosion resistance to seawater is not considered. In general, a material having general water resistance, for example, a stainless steel material can be used, and the energy of the temperature difference due to the multiple stages of the steam power cycle can be reduced while reducing the cost of each steam power cycle unit 10 and 20. Effective utilization can be realized without difficulty, and the performance of the system can be enhanced.

In the desalination and ocean temperature difference power generation system according to the embodiment, the two steam power cycle units 10 and 20 are combined to have a two-stage configuration in which a low-temperature fluid is commonly used. , Four-stage configuration such as four-stage configuration. In this case, similarly to the above embodiment, the steam generated in the seawater desalination apparatus 60 is supplied to an evaporator in one steam power cycle unit to exchange heat with the working fluid, thereby evaporating the working fluid and evaporating the steam. On the other hand, while condensing, the remaining seawater not evaporated by the seawater desalination device 60 is supplied to the evaporator of the other steam power cycle unit to exchange heat with the working fluid, thereby lowering the temperature of the remaining seawater while evaporating the working fluid. Will be done. By increasing the number of stages in the steam power cycle section, the temperature of the working fluid in each evaporator approaches the temperature of the high-temperature fluid that exchanges heat, and the temperature of the working fluid also in each condenser approaches the temperature of the low-temperature fluid that exchanges heat. In addition, the energy of the temperature difference can be effectively used, and the thermal efficiency of the entire system can be further improved.

(Second embodiment of the present invention)
A second embodiment of the present invention will be described with reference to FIG.
In FIG. 8, the desalination and ocean temperature difference power generation system 2 according to the present embodiment includes a plurality of steam power cycle units 10 and 20, a seawater desalination device 60, and a deaeration device 70 as in the first embodiment. On the other hand, the difference is that each of the steam power cycle units 10 and 20 operates in a working fluid flow path between the evaporators 11 and 21 and the turbines 12 and 22 and exits the evaporators 11 and 21. The fluid is separated into a gas phase component and a liquid phase component, and the gas phase working fluid is directed to the turbines 12 and 22, while the liquid phase working fluid is directed to a predetermined portion of the working fluid flow path of a different steam power cycle unit. The gas- liquid separators 16 and 26 are provided, and the liquid surface position of the liquid-phase working fluid in the working fluid circulation channel is set to be higher than the evaporators 11 and 21.

In the desalination and ocean temperature difference power generation system 2 of the present embodiment, the evaporators 11, 21, the turbines 12, 22, and the condenser 13 other than the gas- liquid separators 16, 26 in the respective steam power cycle units 10, 20. , 23, the pumps 14, 24, the power generators 51, 52, the seawater desalination device 60, and the deaerator 70 have the same configuration as in the first embodiment, and a description thereof will be omitted.

The gas- liquid separators 16 and 26 convert the working fluid in a gas-liquid two-phase state by evaporation of the liquid-phase working fluid in the evaporators 11 and 21 into a gas phase after leaving the evaporators 11 and 21. This is a device that separates into a liquid phase component and a liquid phase component. The mechanism of gas-liquid separation itself is the same as a known gas-liquid separator used in a steam power cycle, and detailed description is omitted.

The gas-liquid separator 16 in one steam power cycle unit 10 converts the working fluid in a gas-liquid two-phase state by evaporation through heat exchange with steam in the evaporator 11 into a gas phase component and a liquid phase component. What separates. The working fluid is separated into a gas phase component and a liquid phase component in the gas-liquid separator 16, and the gas phase working fluid flows to the turbine 12 through a working fluid circulation channel communicating with the turbine 12 inlet side.

On the other hand, a part of the liquid-phase working fluid passes through a flow path that connects the liquid-phase working fluid outlet of the gas-liquid separator 16 to the gas-liquid separator 26 in the other steam power cycle unit 20, and is subjected to gas-liquid separation. Into the vaporizer 26 and joins with the working fluid flowing from the evaporator 21 into the gas-liquid separator 26.

In this manner, a part of the liquid-phase working fluid flowing from the gas-liquid separator 16 in one steam power cycle unit 10 to the gas-liquid separator 26 in another steam power cycle unit 20 is combined with the one steam power cycle unit 10 and the other. The working fluid evaporates due to the pressure difference between the working fluid and the steam power cycle unit 20, becomes a gas-phase working fluid, and travels to the turbine 22 together with the other gas-phase working fluid in the gas-liquid separator 26.

The gas-liquid separator 26 in the other steam power cycle unit 20 converts the working fluid in a gas-liquid two-phase state by evaporation through heat exchange with residual seawater in the evaporator 21 into a gas phase component and a liquid phase component. Is divided into The working fluid is separated into a gas phase component and a liquid phase component in the gas-liquid separator 26, and the gas phase working fluid flows to the turbine 22 through a working fluid circulation channel that communicates with the turbine 22 inlet side.

On the other hand, a part of the liquid-phase working fluid communicates with the liquid-phase working fluid outlet of the gas-liquid separator 26 and a predetermined portion of the liquid-phase working fluid flow path on the upstream side of the evaporator in one steam power cycle unit 10. After passing through the flow path, while being pressurized by the auxiliary pump 27 in the middle of the flow path, the liquid flows into the working fluid flow path of the one steam power cycle unit 10 and flows from the pump 14 to the evaporator 11. Join.

In this way, part of the liquid-phase working fluid flowing from the gas-liquid separator 26 in the other steam power cycle unit 20 to the working fluid flow path of one steam power cycle unit 10 evaporates together with the other joined liquid-phase working fluid. It turns to the container 11.

In addition, in each of the steam power cycle units 10 and 20, the working fluid is separated from the working fluid by providing the gas- liquid separators 16 and 26 in the working fluid flow paths between the evaporators 11 and 21 and the turbines 12 and 22. By adjusting the flow rate or the like, the liquid surface position of the liquid-phase working fluid in the working fluid circulation flow path of each of the steam power cycle units 10 and 20 is set above the evaporators 11 and 21.

As a result, the evaporator 11 of the one steam power cycle unit 10 operates with the steam in the evaporator 11 while maintaining the liquid-phase working fluid in the entire flow path of the second flow path 15c through which the working fluid flows. Heat can be exchanged with the fluid.

Further, in the evaporator 21 of the other steam power cycle unit 20, the residual seawater and the working fluid remain in the evaporator 21 while the liquid-phase working fluid is present in the entire flow passage of the first flow passage 15d through which the working fluid flows. Can be heat exchanged.

As described above, in each of the steam power cycle units 10 and 20, the liquid surface position of the liquid-phase working fluid in the working fluid circulation flow path is set above the evaporators 11 and 21, and the entirety of the working fluid side flow paths of the evaporators 11 and 21 is provided. While the liquid-phase working fluid is allowed to circulate, gas- liquid separators 16 and 26 are provided downstream of the evaporators 11 and 21, and the gas-liquid working fluid and the liquid-phase working fluid are separated by the gas- liquid separators 16 and 26. By allowing only the gas-phase working fluid to further advance the working fluid circulation flow path toward the turbines 12 and 22, the working fluid is evaporated by heat exchange with the high-temperature fluid in each of the evaporators 11 and 21. While the generated gas-phase working fluid travels upward as bubbles, the liquid-phase working fluid that has not evaporated travels to the outlet side of the flow path, and can flow out of the evaporators 11 and 21. The ascent of the flow path in the evaporator continues Never vapor phase working fluid from staying on the top of the channel. Therefore, the gas-phase working fluid accumulates in the upper part of the flow path and hinders the contact between the liquid-phase working fluid and the surface of the heat exchange plate, and the heat exchange between the liquid-phase working fluid and the high-temperature fluid and the accompanying evaporation of the working fluid occur. It is possible to reliably prevent the state from being performed smoothly.

Further, in the evaporators 11 and 21, it is possible to ensure a state in which the entire surface of the heat exchange plate facing the flow path on the working fluid side is wet with the liquid-phase working fluid, and the heat transfer of the heat exchange plate 15 in the evaporators 11 and 21 is ensured. Heat exchange can be performed effectively using the area, and the evaporators 11 and 21 can efficiently evaporate the working fluid. Since the gas-phase working fluid and the liquid-phase working fluid can be surely separated by the gas- liquid separators 16 and 26 at the latter stage of the evaporator, the liquid-phase working fluid may be directed to the turbine side by mistake. There is no adverse effect.

When the liquid surface position of the liquid-phase working fluid is positioned above the evaporators 11 and 21 in this manner, the heat exchange unit 11a is provided in the inner space of the shell 11b as in the evaporator 11 in the first embodiment. It is not necessary to dispose it at an angle. As shown in FIG. 9, in the shell 11b of the evaporator 11, the opening portion on the working fluid outflow side and the opening portion on the working fluid inflow side of the second flow path 15c of the heat exchange part 11a are provided. The position in the up-down direction of the portion may be the same, and the heat exchange section 11a may not be inclined.

Further, the liquid-phase working fluid separated by the gas-liquid separator 16 of the one steam power cycle unit 10 is caused to flow into the gas-liquid separator 26 of the other steam power cycle unit 20 so that the low-pressure flow path is formed. The gas-phase working fluid can be increased in the gas-liquid separator 26 as the liquid-phase working fluid flows into and partially evaporates into the liquid-phase working fluid, while the gas-liquid separator 26 in the other steam power cycle unit 20 is increased. The working fluid in the liquid phase separated by the above is allowed to flow into a predetermined portion of the liquid working fluid flow path on the upstream side of the evaporator 11 in the one steam power cycle unit 10 and returned there. , The flow rate of the gas-phase working fluid is increased in the other steam power cycle section 20 while the power obtained in one steam power cycle section 10 is almost maintained. Obtained by the work of fluid It is possible to increase the power output by increasing the force, the ability to more effectively utilize the energy of the temperature difference.

A flow control valve 28 is provided in a flow path that connects the liquid-phase working fluid outlet of the gas-liquid separator 16 in one steam power cycle unit 10 and the gas-liquid separator 26 in the other steam power cycle unit 20. The amount of the liquid-phase working fluid separated by the gas-liquid separator 16 may be adjusted to flow into the gas-liquid separator 26, and the flow rate of the gas-phase working fluid in each of the steam power cycle units 10 and 20 may be adjusted. To increase the power obtained in one steam power cycle section 10 while decreasing the power obtained in another steam power cycle section 20, or conversely, obtain the power obtained in one steam power cycle section 10. The power obtained by the other steam power cycle unit 20 can be increased while the power is reduced, and the temperature of the steam and the residual seawater supplied from the evaporation unit 61 and the deep seawater flowing through the condensers 13 and 23 can be reduced. Temperature, etc., it is possible to optimize the power available in each steam power cycle unit 10, 20 in response to changes in ambient environmental conditions, to obtain the appropriate power output from the whole system.

In this case, the adjustment degree (opening degree) of the flow control valve 28 may be changed in accordance with a change in the flow rate of the liquid-phase working fluid in the gas-liquid separator 16 in one steam power cycle unit 10. Thus, the power automatically obtained in each of the steam power cycle units 10 and 20 can be optimized. In accordance with this, the supply amount of the working fluid by the pump 14 in one steam power cycle unit 10 is changed in accordance with the change in the flow rate of the liquid-phase working fluid in the gas-liquid separator 16, The return flow of the liquid-phase working fluid from the gas-liquid separator 26 to the working fluid flow path in one steam power cycle unit 10 by the auxiliary pump 27 in response to the change in the flow rate of the liquid-phase working fluid in the The working fluid supply amount by the pump 24 in the steam power cycle unit 20 may be changed, and the operation state of each steam power cycle unit 10, 20 can be flexibly set by adjusting the circulation of the working fluid. Can be appropriately dealt with.

In addition, in the system according to the embodiment, the liquid-phase working fluid separated by the gas-liquid separator 16 of one steam power cycle unit 10 flows into the gas-liquid separator 26 of another steam power cycle unit 20. However, the present invention is not limited to this, and the liquid-phase working fluid separated by the gas-liquid separator 16 is supplied to the working fluid flow from the evaporator 21 to the gas-liquid separator 26 in another steam power cycle unit 20. It is also possible to adopt a configuration in which the fluid flows into a predetermined portion of the road.

In the system according to the embodiment, the working fluid in the liquid phase separated by the gas-liquid separator 26 of the other steam power cycle unit 20 is the liquid upstream of the evaporator 11 in one steam power cycle unit 10. Although it is configured to flow into a predetermined portion of the phase working fluid flow path, the present invention is not limited to this, and the working fluid in the liquid phase separated by the gas-liquid separator 26 is supplied to the evaporator in one steam power cycle unit 10. It may be configured so as to flow into 11.

(Third embodiment of the present invention)
In the desalination and ocean temperature difference power generation system according to the first embodiment, the evaporator 11 of one steam power cycle unit 10 is combined with the evaporator 61 to form the seawater desalination apparatus 60, and the shell 11b Although the internal space is configured to communicate with the decompression vessel 61a of the evaporator 61, the present invention is not limited to this. As shown in FIG. 10, a shell of the evaporator 19 in one steam power cycle unit 10 is used as a third embodiment. 19b has a predetermined size, and the shell 19b also serves as a depressurizing container of the evaporating section, accommodates the injection section 65b of the evaporating section 65, the seawater introduction flow path, and the like together with the heat exchange section 19a. It is also possible to adopt a configuration in which the part and the condensing part are arranged together in a common shell.

In this case, the evaporating section 65 includes a shell 19b of the evaporator 19 also serving as a decompression container for reducing the internal space to the atmospheric pressure or less, an injection section 65b for seawater injection provided in the shell 19b, and a shell 19b. A mist removing unit 65c for capturing and removing fine water droplets (mist) of seawater mixed in the steam flow toward the heat exchange unit 19a. In the evaporating section 65, the seawater is guided to the spraying section 65b, and is sprayed upward into the inner space below the shell 19b in a mist state. The pressure inside the shell 19b is reduced by the vacuum exhaust device 64 to a pressure equal to or lower than the saturated vapor pressure of water at the same temperature as the seawater injected from the injection unit 65b, as in the above-described embodiment.

The seawater is sprayed upward in the form of mist or water droplets from a number of spraying portions 65b arranged in the shell 19b, and a part of the water changes its phase into steam by flash evaporation, and at the same time, the temperature of the seawater drops. The vapor obtained by evaporation of the water passes through the mist removing section 65c and flows into the heat exchange section 19a in the same shell 19b. Since the evaporation portion and the condensation portion are integrally accommodated in the shell 19b, the pressure loss in the flow of steam from the evaporation side to the condensation side can be reduced.

As described above, in the evaporator 19 of the one steam power cycle unit 10 according to the present embodiment, each unit constituting the evaporating unit 65 and the heat exchange unit 19a are accommodated in the shell 19b, and the evaporating unit and the condensing unit are integrally formed. Since the steam obtained in the evaporating unit 65 can enter the heat exchanging unit 19a as it is, it is easy to maintain the reduced pressure, and it is ensured that the vapor reaches the heat exchanging unit 19a in gas phase and is condensed. As a result, a series of processes from the evaporation to the condensation can be smoothly performed in the shell 19b, the efficiency of the condensation can be increased, and the exhaust from the inside of the shell 19b can be directly guided to the reduced-pressure exhaust device and discharged. The entire apparatus has a simple and compact structure, so that the cost can be reduced.

(Fourth embodiment of the present invention)
A fourth embodiment of the present invention will be described with reference to FIGS.
In each of the drawings, the desalination and ocean temperature difference power generation system according to the present embodiment includes a plurality of steam power cycle units 10 and 20, a seawater desalination device 60, and a deaeration device 70, as in the first embodiment. On the other hand, as a different point, in the evaporator 11 of the one steam power cycle unit 10, a substantially box disposed to cover a predetermined range portion in an opening portion of the first flow path 15b in the heat exchange unit 11a of the evaporator 11 And a substantially tubular non-condensable gas discharge unit 18 that communicates with the inside of the non-condensable gas collection unit 17 and that can discharge the non-condensable gas to the outside of the shell 11b. It has a configuration.

The non-condensable gas collection unit 17 is formed of a substantially box-like body that is partially open, and includes a second flow path in at least one of the upper and lower openings of the first flow path 15b in the heat exchange unit 11a. 15c is provided so as to cover a predetermined range portion near the opening portion on the working fluid inflow side in 15c.

The non-condensable gas discharge unit 18 is formed in a substantially tubular shape, and has one open end communicating with the inner region of the non-condensable gas collection unit 17 and the other open end positioned outside the shell 11b. A pressure reducing device (not shown) is connected to the other open end so that the non-condensable gas collected in the non-condensable gas collecting unit 17 can be discharged to the outside of the shell 11b. It is.

Next, the operation of removing the non-condensable gas in the evaporator based on the above configuration will be described. As a premise, similarly to the first embodiment, the seawater taken from the sea is once guided to the deaerator 70 of the seawater desalination apparatus 1, and after the air in the seawater is removed, the seawater is introduced into the evaporator 61. It is assumed that most of the water in the seawater injected into the space in the decompression vessel 61a of the decompressed evaporator 61 becomes steam by flash evaporation, and the steam flows into the heat exchanger 10.

で は In the evaporator 11, as in the first embodiment, the steam enters the internal space from the upper opening of the shell 11b. Then, the steam proceeds in the internal space of the shell 11b and flows in from the upper and lower openings in the first flow path 15b of the heat exchange unit 11a.

Of the steam, the steam that has flowed into the first flow path 15b from the upper opening portion exchanges heat with the working fluid through the heat exchange plate 15 while traveling downward through the first flow path 15b, and is transferred to the first flow path 15b. It condenses on the surface of the heat exchange plate 15 facing it, and becomes water in the liquid phase. Further, the steam that has flowed into the first flow path 15b from the lower opening portion exchanges heat with the working fluid via the heat exchange plate 15 while traveling upward through the first flow path 15b. And condenses on the surface of the heat exchange plate 15 to become liquid water.

(4) When the steam is condensed, the non-condensable gas flowing into the first flow path 15b together with the steam is separated from the water that has condensed and becomes a liquid phase. This non-condensable gas naturally exits outside the first flow path 15b naturally, and is discharged to the outside of the shell 11b by the reduced-pressure exhaust device 64 through the internal space of the shell 11b. However, in the portion of the first flow path 15b of the heat exchange section 11a that is close to the opening on the working fluid inflow side in the second flow path 15c separating the heat exchange plate, the temperature of the working fluid on the second flow path 15c side Is lower than that of the other parts, the condensation of the vapor easily proceeds, and the generation of non-condensable gas increases. Since a large amount of non-condensable gas is generated in this way, the natural discharge of the non-condensable gas tends to be stagnant in this part, and the accumulated non-condensable gas hinders the contact between the steam and the heat exchange plate 15 as it is. This can lead to a state where vapor condensation does not proceed.

On the other hand, the non-condensable gas collection unit 17 is arranged so as to cover a predetermined range of the upper opening of the first flow path 15b in the heat exchange unit 11a that is close to the opening on the working fluid inflow side of the second flow path 15c. The non-condensable gas can be sucked from the first flow path 15b through the non-condensable gas collection unit 17 and the non-condensable gas discharge unit 18 to remove the remaining non-condensable gas, and the steam and heat in the first flow path 15b can be removed. Contact with the surface of the exchange plate and condensation of the vapor by heat exchange can be continued without being hindered by the non-condensable gas.

As described above, in the evaporator 11 that condenses the vapor, the condensation easily proceeds at a low temperature near the second flow path inlet in the first flow path 15b of the heat exchange unit 11a, and the non-condensable gas contained in the vapor stays. The non-condensable gas collecting unit 17 is provided along the easy-to-use area, and the non-condensable gas discharging unit 18 is connected to the non-condensing gas collecting unit 17. Since the condensed gas can be discharged to the outside of the shell from the first flow path 15b, the non-condensable gas remaining in a part of the first flow path 15b can be attracted to the non-condensable gas collection unit 17 and removed, and accumulated in the first flow path 15b. It is possible to appropriately prevent the non-condensable gas from interfering with the contact between the steam and the heat exchange plate 15 and prevent the steam from condensing, so that the condensation can be performed efficiently.

In the evaporator, the non-condensable gas collecting section is provided at the upper opening, but the opening of the first flow path 15b of the heat exchange section 11a on the working fluid inflow side in the second flow path 15c. As long as the opening corresponds to a predetermined range portion close to the portion, the non-condensable gas collecting section 17 may be provided on the lower side as shown in FIG.

(Fifth Embodiment of the Present Invention)
In the evaporator 11 of one steam power cycle unit 10 in the fourth embodiment, the non-condensable gas collection unit 17 is formed in a box shape so as to cover a part of the opening of the first flow path 15b. In addition, as shown in FIGS. 14 to 16, the end of the non-condensable gas collecting unit 17 has a shape in which a plurality of protruding protrusions 17 b are arranged in a tooth shape. Is inserted into the first flow path 15b of the heat exchange section 11a to a predetermined depth, and is fixed to each heat exchange plate 15 sandwiching the first flow path 15b. It is also possible to adopt a configuration that functions as a partition that divides into a part communicating with the internal space of 11b and a part communicating with the non-condensable gas collecting part 17.

In this case, the end portion of the non-condensable gas collecting section 17 partitions the first flow path 15b as a partition, and even if steam flows into a position near the non-condensable gas collecting section 17 in the first flow path opening, the partition section does not. Since it is prevented from proceeding toward the non-condensable gas collection unit 17, the steam that has flowed into the opening portion does not go to the non-condensable gas collection unit 17 but proceeds to the first flow path 15 b as far as possible, and The flow into the condensed gas collecting unit 17 can be suppressed, and the vapor can be prevented from being erroneously discharged through the non-condensable gas collecting unit 17, so that the vapor can be surely condensed without any leakage.

1, 2 Desalination and ocean temperature difference power generation system 10, 20 Steam power cycle unit 11, 21 Evaporator 11a, 21a Heat exchange unit 11b, 21b Shell 11c Water recovery unit 11d, 21c, 21d Pipeline 12, 22 Turbine 13, 23 Condenser 14, 24 Pump 15 Heat exchange plate 15b, 15d First flow path 15c, 15e Second flow path 16, 26 Gas-liquid separator 17 Non-condensable gas collecting part 17b Convex part 18 Non-condensable gas discharge part 19 Evaporator 19a Heat exchange unit 19b Shell 27 Auxiliary pump 28 Flow control valve 40 Storage unit 51, 52 Power generation device 61, 65 Evaporation unit 61a Decompression container 61b, 65b Injection unit 64 Decompression exhaust device 65c the mist removal unit 70 deaerator 71 seawater ejection part 72 reservoir 73 discharge portion

Claims (4)

1. The working fluid in the liquid phase is subjected to heat exchange with a predetermined high-temperature fluid to evaporate the working fluid, and while converting the thermal energy possessed by the obtained gas-phase working fluid into power, while converting the thermal energy into power, A plurality of steam power cycle units for performing heat exchange of the gas-phase working fluid with a predetermined low-temperature fluid to condense, returning the working fluid to a liquid phase and exchanging heat with the high-temperature fluid again, and
   A power generation device that generates power using power converted from thermal energy in the steam power cycle unit,
   Water having at least one or more evaporating means for evaporating at least a part of seawater, and at least one or more condensing means for condensing water evaporated by the evaporating means, wherein the condensing means does not contain salt. And a seawater desalination device for obtaining
   The evaporating means of the seawater desalination apparatus performs flash evaporation in which warm seawater on the surface of the ocean is introduced into a predetermined reduced-pressure space reduced to a pressure lower than the saturated vapor pressure of the seawater and evaporated, and
   In the steam power cycle section, one steam power cycle section is supplied with steam evaporated by the evaporating means of the seawater desalination apparatus as the high-temperature fluid, and the working fluid is condensed when the steam condenses. An evaporator that also serves as a condensing means of the seawater desalination apparatus, and a condenser that is supplied with deep-sea cold seawater as the low-temperature fluid and condenses a gas-phase working fluid,
   Among the steam power cycle units, at least a part of the remaining seawater that has not evaporated even when introduced into the reduced pressure space of the evaporating means in the seawater desalination apparatus is supplied as the high-temperature fluid. An evaporator for evaporating the working fluid, and a condenser for supplying cold seawater deep in the ocean as the low-temperature fluid and condensing a gas-phase working fluid. Differential power generation system.
2. In the desalination and temperature difference power generation system according to claim 1,
   The liquid surface position of the liquid-phase working fluid in the working fluid circulation flow path of each steam power cycle unit is set above each evaporator, and the liquid-phase working fluid exists in the entire working fluid side flow path in the evaporator. Heat exchange with steam or residual seawater in the evaporator,
   A desalination and temperature difference power generation system characterized by providing a gas-liquid separator for separating a gas-phase working fluid and a liquid-phase working fluid downstream of an evaporator in a working fluid circulation channel of each steam power cycle unit. .
3. In the desalination and temperature difference power generation system according to claim 2,
   The liquid-phase working fluid separated by the gas-liquid separator in the one steam power cycle unit is supplied to a predetermined working fluid flow path from the gas-liquid separator or evaporator to the gas-liquid separator in the other steam power cycle unit. Flow into the place,
   The liquid-phase working fluid separated by the gas-liquid separator in the another steam power cycle section is required at a predetermined position in the evaporator or the liquid-phase working fluid flow path upstream of the evaporator in one steam power cycle section. A desalination and temperature-difference power generation system characterized by being pressurized and supplied according to the temperature.
4. The desalination and temperature difference power generation system according to any one of claims 1 to 3,
   A seawater desalination apparatus is provided with a decompression vessel for allowing seawater before being evaporated by the desalination apparatus to flow into an inner decompression space,
   The lower part of the decompression space of the decompression container is a storage tank for temporarily storing seawater into which gas components have been separated by inflow, and foreign matter in the seawater flows into water near the seawater surface at the center of the storage tank. Provide a discharge unit that can be discharged outside the container,
   In the seawater collected in the storage tank, a vortex is generated around the center of the storage tank as a center of flow, and floating foreign matter in the seawater is collected in the center of the storage tank, and the collected foreign matter is discharged from the discharge unit. Characterized desalination and temperature difference power generation system.

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