TWI568680B - Water desalination system and water desalination method - Google Patents

Description

Water making device and water making method Field of invention

The present invention relates to a water generating device and a water producing method.

Background technique

Heretofore, in a steam turbine plant that receives power from steam, water is produced by vapor condensed water discharged from a turbine group and condensed in a rehydrator. For example, as shown in FIG. 5, the steam turbine apparatus disclosed in Patent Document 1 is introduced into the condenser 95 by the heat exchange with the cold seawater 93 by the steam introduced into the rehydrator 92 by the turbine 91. The vapor condensed water stored in the condenser 95 is used as the cooling water of the fresh water generator in the process of being used again as a boiler water supply, whereby the heat recovery effect can be achieved, and energy saving can be achieved as a turbine system. In the configuration of Fig. 5, the cold seawater 93 is introduced into the evaporator 97 in the rehydrator 92 as the warm seawater 96, and the generated vapor is introduced into the condenser 95 to exchange heat with the condensed water 94, thereby generating Fresh water 98.

Advanced technical literature Patent literature

Patent Document 1: Japanese Patent Publication No. 61-161189

However, in today's steam turbine equipment, it is required to increase the efficiency due to the high pressure of the steam conditions, and is introduced into the condenser 95 for condensation of the vapor condensation due to the demand for energy saving in the upper layer. The temperature of the water 94 is increased, and the vapor condensed water tends to be reduced. Therefore, in the above-described conventional structure, the temperature and flow rate of the condensed water which is suitable for the required amount of water generation cannot be handled, and the conventional water generator is limited by the evaporation temperature and the like, and it is difficult to ensure the required amount of water production.

Accordingly, it is an object of the present invention to provide a water producing apparatus and a water producing method which can achieve energy saving and improve water generating efficiency.

The above object of the present invention can be attained by a water generating device comprising: a heater for heating raw material water to generate steam; and a rehydrator for cooling the generated water vapor to generate The distilled water has a first heat exchanger that exchanges heat between the steam and the cooling water, and a second heat exchanger that exchanges heat between the steam and the raw water, and is configured to pass the second The raw material water of the heat exchanger can be introduced into the aforementioned heater.

In the fresh water generator, the first heat exchanger and the second heat exchanger may be configured to be integrated so that the cooling water and the raw material water are not mixed.

The water reeliminator may be configured to have a plurality of heat transfer plates laminated between the two end plates, and the plurality of heat transfer plates are separated into two plate groups by a partition member inserted therein. In this configuration, the first heat exchanger is configured to introduce cooling water from one of the end plates, and to exchange heat with water vapor through one of the plate groups, and to pass the heat-exchanged cooling water from one of the ends. The second heat exchanger is configured to introduce raw material water from the other end plate, and exchange heat with water vapor through the other plate group, and to exchange the raw material water after the heat exchange from the other side. The aforementioned end plate is discharged. According to this configuration, the miniaturization can be achieved and the capacity of the rehydrator can be improved.

Further, the steam turbine apparatus further includes a circulation path configured to allow the steam generated by the boiler to be condensed by the turbine condenser after the turbine is driven to flow back to the boiler, thereby causing the first heat exchanger The turbine condensate generated by the turbine condenser can be made into cooling water in the circulation path.

Moreover, the above object of the present invention can be attained by a water-making method comprising the steps of: heating a step of heating a raw material water with a heater to generate water vapor; and a condensation step by cooling water and The raw material water cools the generated water vapor to generate distilled water, and the heating step introduces the raw material water after heat exchange with the steam in the condensation step into the heater.

According to the present invention, it is possible to provide a water generating device and a water generating method which can achieve energy saving and can improve water generating efficiency.

Simple illustration

Fig. 1 is a system diagram of a water generator according to an embodiment of the present invention.

Fig. 2 is a system diagram showing an important part of the water generator shown in Fig. 1.

Fig. 3 is a perspective view of an important part of the water generating device shown in Fig. 1.

Fig. 4 is a perspective view showing an important part of a water generating device of another embodiment of the present invention.

Figure 5 is a system diagram of a conventional water making device.

Form for implementing the invention

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a system diagram of a water generator according to an embodiment of the present invention. As shown in Fig. 1, the fresh water generator 1 is constructed by assembling the water generating apparatus main body 100 in the system of the steam turbine equipment 50. One example of the steam turbine device 50 includes a boiler 51, a turbine group 52, a turbo condenser 53, a ground condenser 54, a water supply heater 55, and a degasser 56, and these constituent elements are through a circulation path 60. And connected.

The boiler 51 burns a fuel such as heavy oil or liquefied natural gas to generate steam from the supply water, and supplies it to the turbine group 52. The turbine group 52 is a group of steam turbines including, for example, a high-pressure turbine and a low-pressure turbine, and generates power for rotating a propeller or the like of a ship. The turbine condenser 53 can cool the steam discharged from the turbine group 52 by seawater or the like to generate turbine condensate. The generated turbine condensate is heated by a part of the steam introduced into the turbine group 52 by the base condenser 54 and the water supply heater 55 by the operation of the pump 61, and then introduced into the degasser 56 to remove oxygen or the like. . The turbine condensate stored in the degasser 56 is supplied to the boiler 51 by the operation of the pump 62 to be vaporized, and circulated to the circulation path 60. The steam turbine device 50 is preferably mounted on a steam turbine, for example, but the application is not particularly limited, and for example, it may be used for power generation.

The fresh water generator body 100 is sandwiched between the pump 61 and the base condenser 54 via the branch path 63 in the steam turbine device 50 having the above configuration, and will pass through the turbine of the circulation path 60 as will be described later. The condensed water is used as cooling water for water generation. The flow rate of the turbine condensate supplied to the fresh water generator body 100 can be adjusted by operating the regulating valve 64 provided in the circulation path 60. The fresh water generator body 100 may be directly inserted in the middle of the circulation path 60 instead of being diverted from the circulation path 60 as in the present embodiment.

Fig. 2 is a system diagram of the water generator body 100. As shown in Fig. 2, the fresh water generator main body 100 includes a heater 10 that heats seawater as raw material water to generate steam, and the evaporator 20 is a concentrated raw material such as steam and brine (concentrated seawater). The water separator; and the rehydrator 30 are those that cool the water vapor to generate distilled water.

The heater 10 has a raw water inlet port 11 for introducing and discharging raw material water, a water vapor/salt outlet 12, and a warm water inlet port 13 and a warm water drain for introducing and discharging warm water such as a water jacket cooling water for a ship. At the outlet 14, the raw material water introduced from the raw material water introduction port 11 is heated by the warm water introduced from the warm water introduction port 13 to be evaporated, and then discharged from the steam ‧ brine outlet 12 . The heater 10 is preferably a plate heat exchanger as in the case of the rehydrator 30 to be described later, but the type of the heat exchanger is not particularly limited. Further, the heating source of the water vapor is not limited to being warm water, and may be, for example, a vapor, a combustion heater or an electric heater.

The evaporator 20 has a heating raw material water introduction port 21 for introducing heated raw water discharged from the steam ‧ brine outlet 12, and a vapor discharge port 22 for discharging water vapor generated by the raw material water; The brine discharge port 23 is a person who discharges residual brine.

The rehydrator 30 includes a vapor introduction port 31 for introducing water vapor discharged from the vapor discharge port 22, and a distilled water discharge port 32 for discharging distilled water obtained by cooling the steam; respectively, introducing and discharging the steam for cooling The cooling water introduction port 33 and the cooling water discharge port 34 of the cooling water; and the raw material water introduction port 35 and the raw material water discharge port 36 for introducing and discharging the raw material water which can also cool the steam, respectively.

In the cooling water introduction port 33, the turbine condensate of the steam turbine device 50 shown in Fig. 1 is introduced as cooling water, and the cooling water discharged from the cooling water discharge port 34 is returned to the circulation path 60 of the steam turbine device 50 again. Since the turbine condensate which is the cooling water is usually high-purity water, the water separator 30 is provided with the partition member 37 so that the cooling water and the raw material water do not mix. The water separator 30 is separated into a first heat exchanger 310 that exchanges heat between steam and cooling water, and a second heat exchanger 320 that exchanges heat between the water vapor and the raw material water. The cooling water does not have to be clean water, and it may be other coolant than the raw water.

In the raw material water introduction port 35, seawater is introduced as raw material water by the operation of the other system or the jet pump 41, and the raw material water discharged from the raw material water discharge port 36 is introduced into the raw material water introduction port 11 of the heater 10. In addition to the seawater of this embodiment, raw water can be used for tap water, rainwater, groundwater, river water, industrial drainage, and domestic drainage. The raw material water supplied from the jet pump 41 can also be used as the driving water of the water ejector 40, and the evaporator 20 and the rehydrator 30 attract the non-condensed gas by being connected to the maximum negative pressure portion of the water ejector 40. Maintain a vacuum. The distilled water discharged from the distilled water discharge port 32 is introduced into a clean water tank (not shown) by the distilled water pump 42.

The rehydrator 30 of this embodiment is constituted by a plate heat exchanger. As shown in the perspective view of the important part of Fig. 3, the rehydrator 30 is disposed between the two end plates 111 and 112, and is configured by alternately stacking two kinds of heat transfer plates 113a and 113b, respectively, and the edge portions are connected by a connecting rod. 30a, 30b combined. Further, in Fig. 3, in order to facilitate understanding of the structure, one end plate 111 is shown by a broken line. Each of the heat transfer plates 113a and 113b is formed in a rectangular shape, and the partition member 37 described above is provided between the two heat transfer plates 113b and 113b disposed adjacent to the center of the stacking direction. Each of the heat transfer plates 113a and 113b is separated into two plate groups by the partition member 37. The partition member 37 of the present embodiment is configured such that the opening of the thicker plate of the heat transfer plates 113a and 113b is sealed by the port plug 37a, and the cooling water can be used even when the cooling water is high-pressure turbine condensate. High pressure resistance, which can prevent the cooling water from mixing with the raw water. However, the configuration of the partition member 37 is not limited to the embodiment. For example, as shown in Fig. 4, the partition member 37 may be constituted by two heat transfer plates 113a and 113b disposed adjacent to each other. The two heat transfer plates 113a and 113b constituting the partition member 37 shown in Fig. 4 have the distillation flow ports 114 and 115 which will be described later. On the other hand, the openings other than these are sealed by the port plug 37a. In addition, in the fourth drawing, the same components as those in the first drawing in Fig. 4 are denoted by the same reference numerals.

The vapor introduction port 31 and the distilled water discharge port 32 are respectively formed on one of the opposite ends of one of the end plates 111. Each of the heat transfer plates 113a and 113b has a distillation flow port 114 and 115 formed at a position corresponding to the steam introduction port 31 and the distilled water discharge port 32, and a vapor introduction port 31 is connected to a flow path formed by each of the distillation flow ports 114. The distilled water discharge port 32 is connected to the flow path formed by each distillation flow port 115.

The cooling water introduction port 33 and the cooling water discharge port 34 are respectively formed at opposite corners of the other one of the end plates 111. Each of the heat transfer plates 113a and 113b constituting one of the plate groups disposed between the one end plate 111 and the partition member 37 is formed with cooling water at a position corresponding to the cooling water introduction port 33 and the cooling water discharge port 34. The flow ports 116 and 117 are connected to the cooling water introduction port 33 via a flow path formed by each of the cooling water circulation ports 116, and the cooling water discharge port 34 is connected to the flow path formed by each of the cooling flow ports 117.

The raw material water introduction port 35 and the raw material water discharge port 36 are respectively formed at opposite corners of the other end plate 112. Each of the heat transfer plates 113a and 113b constituting the other plate group disposed between the other end plate 112 and the partition member 37 is formed at a position corresponding to the raw material water introduction port 35 and the raw material water discharge port 36, respectively. The raw material water outlets 118 and 119 are connected to the raw material water introduction port 35 via a flow path formed by each raw material water outlet port 118, and the raw material water discharge port is connected to the flow path formed by each raw material flow port 119. 36. The partition member 37 has the distillation flow ports 114 and 115. On the other hand, as described above, the opening corresponding to the cooling water flow ports 116 and 117 and the raw material water circulation ports 118 and 119 is sealed by the port plug 37a.

Each of the heat transfer plates 113a and 113b is formed with a groove portion 120a and 120b, and the groove portion 120a of the heat transfer plate 113a communicates between the two distillation flow ports 114 and 115. On the other hand, between the two cooling water flow ports 116 and 117 Or the two raw material water circulation ports 118 and 119 are isolated. Further, the groove portion 120b of the heat transfer plate 113b separates between the two distillation flow ports 114 and 115, and the two cooling water flow ports 116 and 117 or between the two raw material water supply ports 118 and 119 communicate with each other. The adjacent heat transfer plates 113a and 113b are sealed by a gasket (not shown). In addition, in FIG. 3, in order to make it easy to understand, the flow path formed in the lamination direction of the heat transfer plates 113a and 113b shows the part which communicates with the groove parts 120a and 120b by the broken line, and shows the part isolate|separated from the groove part 120a and 120b by the solid line. .

In the above-described structure of the rehydrator 30, the water vapor and the cooling water introduced from the vapor introduction port 31 and the cooling water introduction port 33 are respectively passed through the heat transfer plate 113a between the one end plate 111 and the partition member 37. Since the groove portion 120a and the groove portion 120b of the heat transfer plate 113b, the water vapor and the cooling water alternately pass between the adjacent heat transfer plates 113a and 113b as viewed in the stacking direction of the heat transfer plates 113a and 113b. As a result, heat exchange is performed between the steam and the cooling water through the heat transfer plates 113a and 113b, and this portion functions as the first heat exchanger 310. The distilled water and the cooling water generated by the end of the heat exchange are discharged from the distilled water discharge port 32 and the cooling water discharge port 34, respectively.

Between the other end plate 112 of the rehydrator 30 and the partition member 37, the raw material water introduced from the raw material water introduction port 35 flows through the groove portion 120b of the heat transfer plate 113b, and therefore, the heat transfer plates 113a, 113b In the direction of the lamination, the water vapor and the raw material water alternately pass between the adjacent heat transfer plates 113a, 113b. As a result, heat exchange is performed between the steam and the raw material water through the heat transfer plates 113a and 113b, and this portion functions as the second heat exchanger 320. The raw material water heated to end the heat exchange is discharged from the raw material water discharge port 36.

According to the fresh water generator 1 having the above-described structure, the cooling water introduced from the end plate 111 of one of the rehydrators 30 through the cooling water introduction port 33 and the cooling water introduced from the other end plate 112 through the raw material water introduction port 35 are introduced. The raw material water is heat-exchanged with the steam in the first heat exchanger 310 and the second heat exchanger 320, whereby the distilled water can be formed. Therefore, it is conventionally known that only the cooling water and the steam are exchanged. The configuration makes it easier to condense water vapor, which improves the efficiency of the rehydrator 30. In addition, since the raw material water which is heated by the heat exchange with the water vapor in the second heat exchanger 320 is introduced into the heater 10, the raw material water introduced into the heater 10 can be evaporated in the initial stage to improve the heat exchange efficiency. Energy saving can be achieved. The temperature of the raw material water introduced into the heater 10 can be appropriately adjusted by selecting the number of heat transfer plates 113a and 113b provided in the rehydrator 30 or the position of the partition member 37.

The above-described effects of the fresh water generator 1 can be particularly remarkable in the case where the turbine condensate of the steam turbine device 50 is used as the cooling water as in the present embodiment, even if the steam condensate is heated as the steam condition is increased. High temperatures also make it easy to ensure the amount of water needed. However, the cooling water introduced into the rehydrator 30 does not necessarily have to be limited to the turbine condensate of the steam turbine apparatus 50. For example, condensed water generated by other vapor circulation systems may be used, or by using steam as a heat source or a power source. It is used to generate and maintain high temperature and is used for drainage water for other purposes.

Further, in the present embodiment, since the first heat exchanger 310 and the second heat exchanger 320 are integrated so that the cooling water and the raw material water are not mixed, the structure can be reduced in size and the complex can be improved. The efficiency of the water 30. Specifically, the first heat exchanger 310 and the second heat exchanger 320 may be arranged side by side in the stacking direction of the heat transfer plates 113a and 113b. In the configuration of the present embodiment, the water vapor introduced into the rehydrator 30 is initially introduced into the first heat exchanger 310, and the remaining water vapor is introduced into the second heat exchanger 320. However, the arrangement of the first heat exchanger 310 and the second heat exchanger 320 is not limited to the embodiment. For example, the cooling water introduction port 33 and the cooling water discharge port 34 may be provided in the other. In the end plate 112, the raw material water introduction port 35 and the raw material water discharge port 36 are provided in one end plate 111.

Further, the first heat exchanger 310 and the second heat exchanger 320 are preferably formed by a plate heat exchanger as in the present embodiment, but other heat exchangers such as a shell and tube type may be used. Further, the first heat exchanger 310 and the second heat exchanger 320 do not have to be integrated, and may be separated from each other. The first heat exchanger 310 and the second heat exchanger 320 may be configured to introduce the water vapor flow into the first heat exchanger 310 and the second heat exchanger 320, respectively.

1. . . Water generator

10. . . Heater

11. . . Raw material water inlet

12. . . Water vapor ‧ brine outlet

13. . . Warm water inlet

14. . . Warm water discharge

20. . . Evaporator

twenty one. . . Heating raw material water inlet

twenty two. . . Vapor discharge

twenty three. . . Brine discharge

30. . . Rehydrator

30a, 30b. . . Link rod

31. . . Vapor introduction port

32. . . Distilled water discharge

33. . . Cooling water inlet

34. . . Cooling water drain

35. . . Raw material water inlet

36. . . Raw material water discharge

37. . . Separating member

37a. . . Mouth plug

40. . . Water jet

41. . . Jet pump

42. . . Distillation pump

50. . . Steam turbine equipment

51. . . boiler

52. . . Turbine group

53. . . Turbo condenser

54. . . Base condenser

55. . . Water supply heater

56. . . Degasser

60. . . Loop path

61, 62. . . Pump

91. . . turbine

92. . . Rehydrator

93. . . Cold sea water

94. . . Condensate

95. . . Condenser

96. . . Warm sea water

97. . . Evaporator

98. . . freshwater

100. . . Water generator body

111, 112. . . End plate

113a, 113b. . . Heat transfer plate

114, 115. . . Distillation port

120a, 120b. . . Ditch

310. . . First heat exchanger

320. . . Second heat exchanger

Fig. 1 is a system diagram of a water generator according to an embodiment of the present invention.

Fig. 2 is a system diagram showing an important part of the water generator shown in Fig. 1.

Fig. 3 is a perspective view of an important part of the water generating device shown in Fig. 1.

Fig. 4 is a perspective view showing an important part of a water generating device of another embodiment of the present invention.

Figure 5 is a system diagram of a conventional water making device.

10. . . Heater

11. . . Raw material water inlet

12. . . Water vapor ‧ brine outlet

13. . . Warm water inlet

14. . . Warm water discharge

20. . . Evaporator

twenty one. . . Heating raw material water inlet

twenty two. . . Vapor discharge

twenty three. . . Brine discharge

30. . . Rehydrator

31. . . Vapor introduction port

32. . . Distilled water discharge

33. . . Cooling water inlet

34. . . Cooling water drain

35. . . Raw material water inlet

36. . . Raw material water discharge

37. . . Separating member

40. . . Water jet

41. . . Jet pump

42. . . Distillation pump

100. . . Water generator body

310. . . First heat exchanger

320. . . Second heat exchanger

Claims (3)

A fresh water generating device comprising: a heater for heating raw material water to generate steam; and a rehydrator for cooling water generated to generate distilled water, wherein the rehydrator has water vapor and cooling water a first heat exchanger for heat exchange and a second heat exchanger that exchanges heat between the steam and the raw material water, and the raw material water passing through the second heat exchanger can be introduced into the heater, and the rehydrator has a laminate a plurality of heat transfer plates disposed between the two end plates, wherein the plurality of heat transfer plates are separated into two plate groups by a partition member inserted therein, and the first heat exchanger is configured to be introduced from one of the end plates The cooling water is exchanged with the steam by one of the above-mentioned plate groups, and the heat-exchanged cooling water is discharged from one of the end plates, and the second heat exchanger is configured to introduce the raw material from the other end plate. The water is exchanged with the water vapor through the other plate group, and the heat exchanged raw material water is discharged from the other end plate. The water generating device of claim 1, further comprising a steam turbine device configured to have a circulation path for causing steam generated by the boiler to be condensed by the turbine condenser after the turbine is driven to flow back to the boiler And the first heat exchanger is interposed in the circulation path, and the turbine condensate generated by the turbo condenser is used as cooling water. A water-making method using the water-producing device according to claim 1, wherein the water-making method comprises the steps of: heating a step of heating the raw material water with the heater to generate water vapor; and condensing the step to rehydrate the water The distilled water is generated by cooling the generated water vapor by the cooling water and the raw material water, and the heating step introduces the raw material water after the heat exchange with the steam in the condensation step into the heater.