JPH0450041B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a dual-effect evaporator used to obtain fresh water from seawater, in particular, the second effect (low-temperature effect) is used to obtain fresh water from seawater. Improvement of a so-called vapor compression type double effect evaporator in which steam is suctioned and compressed by an ejector driven by pressure steam from outside the system, and mixed steam from the ejector is used as heating steam for the first effect (high temperature effect). It is related to.

[Conventional technology]

This type of vapor compression type double effect evaporator is disclosed in Japanese Utility Model Publication No. 54-39472 as a prior art.

The vapor compression type double-effect evaporator disclosed in this prior art is, as shown in FIGS. 1 to 4,
First, the casing A1 in the first effect A is formed into a rectangular parallelepiped sealed box, and the inside of the casing A1 is connected to an evaporation chamber A3 and a steam chamber A4 through a vertical plate A2, so that both chambers communicate with each other at the bottom. In the evaporation chamber A3, there is a heat exchanger tube group A7 having headers A5 and A6 on the front and rear outer sides of the casing A1.
are arranged horizontally, and dispersion means A8 is provided above the heat exchanger tube group A7 to spray seawater onto the surface of each heat exchanger tube in the heat exchanger tube group A7, while the casing B1 in the second effect B is also installed. Similarly, the casing B is formed into a rectangular parallelepiped sealed box.
1 is divided into an evaporation chamber B3 and a vapor chamber B4, which communicate with each other by a vertical plate B2, so that both chambers communicate with each other at the lower part, and the casing B is in the evaporation chamber B3.
A heat exchanger tube group B7 having headers B5 and B6 on the left and right outer sides of the heat exchanger tube group B7 was arranged horizontally, and seawater was sprinkled on the surface of each heat exchanger tube in the heat exchanger tube group B7 above the heat exchanger tube group B7. Spreading means B8
The first effect A and the second effect B are arranged such that the heat exchanger tube groups A7 and B7 in both of them are at right angles to each other in plan view.

Then, by connecting the discharge side of a pressure steam-driven ejector C whose suction port is connected to the steam chamber B4 of the second effect B via a pipe D to one header A5 of the first effect A, In the evaporation chamber A3 in the first effect A, steam is generated from the seawater sprayed down from the dispersion means A8, and this steam is transferred from the steam chamber A4 to the second effect B through the large diameter pipe E.
into one header B5 of the second header.
Spreading means B in the evaporation chamber B3 in effect B
Steam is generated from the seawater sprayed down from 8,
This steam is sucked into the ejector C from the steam chamber B4, while the condensed water in the heat transfer tube group A7 in the first effect A is transferred to the other header A6.
After leading to one header B5 in the second effect B via the pipe F, the fresh water is taken out from the other header B6 together with the condensed water in the heat transfer tube group B7 in the second effect B through the pump-equipped pipe G. This is what I did.

In Figures 1 to 4, H is a seawater supply pipe with a pump to the dispersion means B8 in the second effect B, and I is a seawater supply pipe with a pump to the dispersion means B8 in the second effect B. A transfer pipe with a pump for transferring to the dispersion means A8 in the first effect A, J a delivery pipe with a pump for taking out the unevaporated seawater accumulated at the bottom of the casing A1 in the first effect A, and K a bleed air for vacuum generation. It is an ejector.

On the other hand, this type of vapor compression type double-effect evaporator that produces fresh water from seawater is used in emergency situations such as supplying drinking water or domestic water to local drought areas, or at construction sites. In many cases, they were used temporarily to secure water for boilers and daily use for workers, and when they were no longer needed, they were moved to other locations for use.

Therefore, this evaporator is compact, lightweight, and has an economical structure that can significantly reduce on-site assembly and installation costs. Furthermore, it is easy to operate and maintains high performance. is required.

[Problem that the invention seeks to solve]

However, the vapor compression type double effect evaporator in the prior art has the first effect A and the second effect A as described above.
Since effect B and effect B are manufactured separately and installed on site, they are connected using ejector C and large diameter pipe E, etc., so a considerable amount of man-hours are required for installation and assembly on site. In addition, the first effect A and the second effect B must be installed separated by a distance equal to the length of the ejector C, which increases the installation area.

Moreover, the evaporator in the prior art has a casing A in a first effect A and a second effect B.
1. Inside B1 is divided into evaporation chambers A3, B3 on the right side and steam chambers A4, B4 on the left side by vertical plates A2, B2, and inside evaporation chambers A3, B3 on the right side in casings A1, B1. Since the structure is such that all of the generated steam is guided to the steam chambers A4 and B4 on the left side of the casing, the steam generated in the part of the evaporation chamber that is farther from the steam chamber crosses the evaporation chamber and enters the steam chamber. The length of the steam path becomes longer.

For this reason, the area in which the generated steam comes into contact with the seawater flowing down inside the evaporation chamber becomes longer, and the amount of seawater droplets included in the generated steam flowing into the steam chamber increases.
The purity of the fresh water produced decreases.Moreover, as the distance of the steam passage becomes longer, the flow resistance of the steam increases, and the pressure loss of the flowing steam in the passage increases, resulting in a decrease in evaporation efficiency and a reduction in transmission. The amount of evaporation per unit heat transfer area in the heat tube group was reduced.

Therefore, the first invention solves the various problems described above in the prior art, and the second invention
This invention is intended to further promote the effects of the first invention.

[Means for solving problems]

Therefore, in the first invention, a cylindrical casing provided with end plates at both ends in the axial direction is installed horizontally so that the axis thereof is substantially horizontal, and the inside of the casing is provided with a partition wall plate extending in the axial direction. The first effect zone and the second effect zone are divided into a first effect zone and a lower second effect zone, and the first effect zone and the second effect zone are further located between two steam chambers by a partition plate extending in the axial direction of the casing. The evaporation chamber is divided into an evaporation chamber and both steam chambers so as to communicate with each other at the lower part, and the evaporation chamber in the first effect zone and the second effect zone has a header on the outer surface of both end plates of the casing. A group of heat transfer tubes is disposed approximately parallel to the axis of the casing, and a dispersing means is provided above the group of heat transfer tubes to spray seawater onto the surface of the group of heat transfer tubes. A steam outlet provided in the steam chamber is connected to a header of a heat exchanger tube group in a second effect zone, and a steam-driven ejector connected to the steam outlet in both steam chambers of the second effect zone is connected to the outside of the casing. The ejector is arranged to extend in the axial direction, and the discharge sides of both ejectors are connected to the header of the heat exchanger tube group in the first effect zone.

Further, in addition to the first invention, a second invention provides that the steam outlets provided in both steam chambers in the first effect zone are provided at two locations near both end plates of the casing, while the steam outlets in the second effect zone are provided at two locations near both end plates of the casing. The steam outlets in both steam chambers are also located at two locations near both end plates of the casing, and an ejector is connected to each of the four steam outlets.

〔Example〕

An example of an embodiment in which the second invention is added to the first invention will be described below with reference to the drawings. The casing 1 is mounted on a foundation 4 with legs 5, so that its axis is approximately horizontal.
It is installed horizontally via 6.

A partition plate 7 extending in the axial direction of the casing 1 is provided in the casing 1 to divide it into an upper first effect zone 8 and a lower second effect zone 9.

Further, inside the first effect zone 8, the casing 1
two vertical partition plates 10 extending in the axial direction of the
10, the evaporation chamber 11 at the central position and the steam chambers 12, 12 on the left and right sides thereof are divided so that the evaporation chamber 11 and the steam chambers 12, 12 communicate with each other at the lower part. Inside the zone 9, two vertical partition plates 13, 13, which also extend in the axial direction of the casing 1, divide the evaporation chamber 14 into an evaporation chamber 14 at the center and steam chambers 15, 15 on both the left and right sides of the evaporation chamber 14. and steam chambers 15, 15 are configured so as to communicate with each other at the lower part.

In the evaporation chamber 11 in the first effect zone 8 and in the evaporation chamber 14 in the second effect zone 9,
The heat exchanger tube groups 16 and 17 are provided substantially parallel to the axis of the casing 1, and headers 18 and 19 are provided at both ends of the heat exchanger tube group 16 in the first effect zone 8, and headers 18 and 19 are provided at both ends of the heat transfer tube group 17 in the second effect zone 9. The headers 20 and 21 are joined to the outer surfaces of both end plates 2 and 3 of the casing 1 via tube plates, while the upper parts of the evaporation chamber 11 in the first effect zone 8 and the evaporation chamber 14 in the second effect zone 9 are The seawater dispersion chambers 22, 23 and the dispersion trays 24, 2 are installed.
Spreading means 26, 27 consisting of 5 etc. are provided.

In addition, each of the headers 18 and 19 in the first effective zone 8 is separated by three vertical partition plates 2.
Four header chambers 18a, 18b, 18c, 18d, 19 at 8, 29, 30, 31, 32, 33
a, 19b, 19c, and 19d, and each of the headers 20, 21 in the second utility zone 9 is divided into three vertical partition plates 34, 35, 36,
Four header chambers 20a at 37, 38, 39,
20b, 20c, 20d, 21a, 21b, 21
It is divided into sections c and 21d.

both steam chambers 12 in the first effect zone 8;
12 is provided with steam outlets 40, 40, 41, 41, respectively, at parts of the casing 1 near both end plates 2, 3, and the steam outlets 40, 40 near the end plate 2 on the left side are connected via pipes 42, 42. , header chamber 20b2 in the second utility header 20 attached to the left end plate 2
Steam outlet 4 connected to 0C and close to the right end plate 3
1, 41 to the right end plate 3 via pipes 43, 43.
It is connected to the header chambers 21a and 21d in the second utility header 21 attached to the header.

Further, in both the steam chambers 15, 15 in the second effect zone 9, steam outlets 44, 44, 45, 45 are respectively provided in the portions of the casing 1 close to both end plates 2, 3, and close to the left end plate 2. Steam outlet 44,4
4 is connected to the suction sides of steam-driven ejectors 46, 46, which are disposed so that their discharge sides face the right end plate 3 of the casing 1, through a pipe 61, and the discharge sides of both ejectors 46, 46 are connected to conduit 4
Header chambers 19b, 19c in the first effect header 19 attached to the right end plate 3 via 7, 47
while the steam outlet 4 close to the right end plate 3
5 and 45 are connected to the suction sides of steam-driven ejectors 48 and 48, which are disposed so that their discharge sides face the left end plate 2 of the casing 1, via a conduit 62. The header chamber 18 in the first effect header 18 attached to the left end plate 2 on the discharge side via the pipes 49, 49
Connect to a and 18d.

A pipe 5 is connected to the seawater spraying means 27 in the second effect.
0, unevaporated seawater collected at the bottom of the first effect zone 8 flows into the bottom of the second effect zone 9 via pipes 51, 51, and then unevaporated seawater accumulated at the bottom of the second effect zone 9. After the evaporated seawater is sucked into the pump 53 through the pipe 52, a part of the seawater is passed through the pipe 54 to the seawater spraying means 26 in the first effect zone 8.
At the same time, the remaining seawater is discharged from the system through a pipe 55. Also, both headers 18, 1 of the first utility
Header chambers 18b, 18c, 19a,
The upper part of 19d is connected to the first
The header chambers 20a, 20 in both headers 20, 21 of the second effect communicate with the evaporation chamber 11 of the effect.
d, 21b, and 21c are connected to piping to a bleed ejector (not shown) for generating vacuum. Moreover, in each steam chamber 12, 12, 15, 15 in the 1st effect zone 8 and the 2nd effect zone 9, the demister 63, 64 is provided, respectively.

When pressurized steam from outside the system is supplied to each ejector 46, 46, 48, 48 from the pipe 56, the second
The generated steam in the evaporation chamber 14 in the effect zone 9 is sucked into each ejector, and then enters the heat transfer tubes of the heat transfer tube group 16 in the first effect zone 8 together with the pressure steam from the tubes 56. Heat tube group 1
Steam is generated from the seawater in the evaporation chamber 11 of the first effective zone 8 by heating the seawater sprayed by the seawater spraying means 26 onto the surface of the first effective zone 8 . The steam generated in the evaporation chamber 11 flows into the steam chambers 12, 12 provided on both sides of the evaporation chamber 11 in left and right directions, and then flows through the steam outlets 40, 41 and the pipe line 42,
43, enters each heat exchanger tube of the heat exchanger tube group 17 in the second effect zone 9, and heats the seawater sprayed on the surface of the heat exchanger tube group 17 by the seawater spraying means 27, thereby producing the second effect. Evaporation chamber 1 in zone 9
4 to generate steam from seawater. This evaporation chamber 1
The steam generated in the evaporation chamber 14 flows into the steam chambers 15, 15 provided on both sides of the evaporation chamber 14, and then flows into the ejector 4 from the steam outlets 44, 45.
6, 48, it is used as a heating source in the first effect zone 8.

And the heat exchanger tube group 16 of the first effect zone 8
The condensed water in each heat transfer tube in both headers 1
Header chambers 18b, 18c, 1 in 8, 19
9a, 19d flows into the steam inlets of the header chambers 20b, 20c, 21a, 21d in both the headers 20, 21 of the second effect zone 9 through the pipes 57, 58, and the sensible heat is transferred to the second After being used as a heat source in the effect zone 9, the header chambers 20a, 20d, 21b, 21c in both the headers 20, 21 of the second effect zone 9 are used together with the condensed water in the heat transfer tube group 17 in the second effect zone 9. Fresh water is taken out from the bottom of the tank as manufactured fresh water through pipes 59 and 60 using a pump (not shown).

In addition, in order to simplify the structure of the header and reduce the number of piping to the condensate outlet pipe and bleed ejector,
In the above embodiment, 18b of each header chamber in both headers 18 and 19 of the first utility zone 8
and 18c and 19b and 19c respectively,
Conduit 4 is installed in the common header room of 19b and 19c.
7 and 47, while connecting 20b and 20c and 21b and 21c of the header chambers in both headers 20 and 21 in the second utility zone 9, respectively, and connecting the pipes to the common header chambers of 20b and 20c. 18a and 18 may be connected in other embodiments.
b, 18c, and 18d are each made common, and conduits 49, 49 are connected to one of these common header chambers, and 19a, 19b, and 19c, and 19d are made common, respectively, and conduits 49, 49 are connected to one of these two common header chambers. 4
Pipe 4 is connected to the header room where 9 and 49 are not connected.
7, 47, while connecting 20a, 20b and 2
0c and 20d are each made common, and the pipes 42 and 42 are connected to one of these common header chambers, and 21a
, 21b, 21c, and 21d may be made common, and the pipe lines 43, 43 may be connected to the header chamber to which the pipe lines 42, 42 are not connected among the two common header chambers.

Both steam chambers 12, 1 of the first effect zone 8
2 steam outlets 40, 40, 4 provided with two each
1, 41 to both the headers 20, 21 of the second effect, if the steam outlets 40, 40, 41, 41 and the headers 20, 21 are connected close to each other as in the previous embodiment. , since the length of the pipes 42 and 43 connecting them becomes shorter,
In addition to simplifying and reducing the weight of piping, the steam chamber 1
This has the advantage that the pressure loss of flowing steam from the headers 2, 12 to the headers 20, 21 can be reduced.

In addition, as in the above embodiment, the second effect zone 9
If the two ejectors 46, 48 connected to one steam chamber 15 out of both the steam chambers 15, 15 are turned in opposite directions, the pipes 61, 62 from the steam outlets 44, 45 to the ejectors 46, 48 will be created. , and the lengths of the pipes 47, 49 from the ejectors 46, 48 to the headers 18, 19 of the first effect are shortened, making it possible to simplify and reduce the weight of the piping, and also to connect the steam chambers 15, 15 to the headers 18. , 19 has the advantage of reducing the pressure loss of the flowing steam.

[Action/effect of the invention]

As described above, according to the first invention, the steam generated in the evaporation chamber in the first effect zone and the second effect zone is divided and flows into the two vapor chambers formed on both sides of the evaporation chamber. Compared to the prior art, in which the generated steam flows from the evaporation chamber to the steam chamber on only one side, there is no place where dead space is created due to the accumulation of generated steam in the evaporation chamber, and moreover, the generated steam is divided into both steam chambers. Since the flow is almost uniform, the flow rate of the steam is slowed down, and the area in which the steam generated in the evaporation chamber comes into contact with the seawater flowing down inside the evaporation chamber is also shortened.

For this reason, the pressure loss of the steam generated in the evaporation chamber from the evaporation chamber to the steam chamber is reduced,
The evaporation efficiency improves, increasing the amount of evaporation per unit heat transfer area in the heat transfer tube group, improving the fresh water production capacity, and reducing the number of seawater droplets accompanying the steam flowing into the steam chamber, improving the purity of the produced fresh water. This improves performance and maintains high performance.

Moreover, in the first invention, the first effect and the second effect are formed in one casing, and the ejector is disposed on the outside of the casing substantially parallel to the axis of the casing. Since the casing can be transported to the site with the ejector attached to it, the number of man-hours required for installation and assembly on site can be reduced by transporting the first and second effects separately, as in the prior art. This is incomparably cheaper than connecting the first effect and the second effect with an ejector, piping, etc., and it is possible to significantly reduce on-site installation/assembly work and transportation costs. The area can be significantly reduced.

Further, the second invention provides a first efficacy zone and a second efficacy zone.
The steam in both steam chambers in the effective zone is extracted from two steam outlets near both end plates of the casing, and this eliminates the partial steam generated when steam in the evaporation chamber is extracted from one location. In other words, the steam flow speed in each steam chamber is approximately equal and gentle at each location in the axial direction of the casing, reducing pressure loss associated with steam flow. At the same time, the amount of seawater droplets accompanying this steam will also decrease.

Therefore, according to the second invention, it is possible to maintain good thermal efficiency, and it is possible to further improve the amount of evaporation per unit heat transfer area in the heat transfer tube group, and thus the fresh water production capacity and the purity of fresh water.

[Brief explanation of the drawing]

Figures 1 to 4 show conventional evaporation equipment, with the first
The figure is a simplified front view of the piping, Figure 2 is a cross-sectional view of Figure 1, Figure 3 is a cross-sectional view of Figure 2, Figure 4 is a cross-sectional view of Figure 2, and Figure 4 is a cross-sectional view of Figure 2. Figure 5~
Fig. 15 shows an embodiment of the present invention, Fig. 5 is a front view, Fig. 6 is a plan view, Fig. 7 is a sectional view taken from - in Fig. 5, and Fig. 8 is a sectional view taken from - in Fig. 7. Figure, No. 9
The figure is a sectional view taken from - in Fig. 7, Fig. 10 is a sectional view taken from - in Fig. 7, Fig. 11 is a sectional view taken from XI-XI in Fig. 7, and Fig. 12 is a sectional view taken from XII-XII in Fig. 8. 13 is a cross-sectional view of FIG. 8, FIG. 14 is a cross-sectional view of FIG. 8, and FIG. 15 is a cross-sectional view of FIG. 8.
FIG. 1... Casing, 2, 3... End plate, 7... Partition plate,
8...First utility zone, 9...Second utility zone, 1
0, 13... Partition plate, 11, 14... Evaporation chamber, 12,
15... Steam chamber, 16, 17... Heat exchanger tube group, 18, 1
9, 20, 21... Header, 26, 27... Seawater spraying means, 40, 41, 44, 45... Steam outlet, 4
6,48...Ejector.

Claims (1)

[Scope of Claims] 1. A cylindrical casing provided with end plates at both ends in the axial direction is installed horizontally so that its axis is approximately horizontal, and the inside of the casing is separated from the upper part by a partition plate extending in the axial direction. It is divided into a first effect zone and a lower second effect zone, and the first effect zone and the second effect zone are further divided into two steam chambers by a partition plate extending in the axial direction of the casing, and an evaporator located between them. The evaporation chamber and both steam chambers are divided into a chamber such that the evaporation chamber and both steam chambers communicate with each other at the lower part, and a first effect zone and a second
Inside the evaporation chamber in the effective zone, a group of heat transfer tubes having headers on the outer surfaces of both end plates of the casing are arranged approximately parallel to the axis of the casing, and seawater is poured onto the top of the group of heat transfer tubes. Provided with a dispersing means adapted to spray on the surface of the
A steam-driven ejector that connects steam outlets provided in both steam chambers in the first effect zone to a header of a heat transfer tube group in a second effect zone, and connects to steam outlets in both steam chambers in the second effect zone. are arranged outside the casing so as to extend in the axial direction thereof, and the discharge sides of both ejectors are connected to the header of the heat transfer tube group in the first effect zone. Evaporation equipment. 2. A cylindrical casing equipped with end plates at both ends in the axial direction is installed horizontally so that its axis is approximately horizontal, and the inside of the casing is divided into an upper first utility zone and a lower part by partition plates extending in the axial direction. The first and second efficacy zones are further divided into two steam chambers and an evaporation chamber located between them by a partition plate extending in the axial direction of the casing. and both steam chambers are configured so as to communicate with each other at the lower part, and a first effect zone and a second
Inside the evaporation chamber in the effective zone, a group of heat transfer tubes having headers on the outer surfaces of both end plates of the casing are arranged approximately parallel to the axis of the casing, and seawater is poured onto the top of the group of heat transfer tubes. Provided with a dispersing means adapted to spray on the surface of the
Both steam chambers in the first effect zone are each provided with a steam outlet at a portion of the casing near both end plates, and each of the four steam outlets is connected to a header of a group of heat exchanger tubes in the second effect zone, Both steam chambers in the second effect zone include:
A steam outlet is provided in a portion of the casing near both end plates, and four steam-driven ejectors are separately connected to each of these four steam outlets, and are arranged so as to extend in the axial direction on the outside of the casing. and the discharge side of each ejector is connected to the first
A vapor compression type double effect evaporator characterized in that it is connected to a header of a group of heat transfer tubes in an effect zone. 3. The steam outlet provided in both steam chambers of the first effect zone near both end plates of the casing and the header of the heat transfer tube group in the second effect zone are connected to each other if they are close to each other. A vapor compression type double effect evaporator according to claim 2. 4. The vapor compression type double effect evaporator according to claim 2, wherein the two ejectors connected to one vapor chamber in the second effect zone are oriented in opposite directions.