CN113526600B

CN113526600B - Desalting and deoxidizing equipment and method

Info

Publication number: CN113526600B
Application number: CN202110673809.0A
Authority: CN
Inventors: 于超; 刘瑶; 郝玉刚; 徐建炎
Original assignee: China ENFI Engineering Corp
Current assignee: China ENFI Engineering Corp
Priority date: 2021-06-17
Filing date: 2021-06-17
Publication date: 2022-07-26
Anticipated expiration: 2041-06-17
Also published as: CN113526600A

Abstract

The invention discloses a desalting and deoxidizing device and a desalting and deoxidizing method, wherein the desalting and deoxidizing device comprises a first heat exchanger, a second heat exchanger and a fifth heat exchanger, the first heat exchanger is provided with a first cavity, a first steam inlet, a first condensed water outlet, a first raw water inlet, a first steam outlet and a first vacuumizing port, and a first heat exchange tube is arranged in the first cavity; the second heat exchanger is provided with a second cavity, a second steam inlet, a second condensed water outlet, a second raw water inlet, a second steam outlet and a second vacuumizing port, a second heat exchange pipe is arranged in the second cavity, and the second steam inlet is communicated with the first steam outlet; the fifth heat exchanger is provided with a fifth cavity, a fifth steam inlet, a fifth condensed water outlet, a fifth cooling liquid inlet and a fifth cooling liquid outlet, a fifth heat exchange tube is arranged in the fifth cavity, and the fifth steam inlet is connected with the second steam outlet. The desalting and deoxidizing equipment disclosed by the embodiment of the invention has the advantages of high energy utilization rate, high water resource utilization rate, high safety of related equipment and the like.

Description

Desalting and deoxidizing equipment and desalting and deoxidizing method

Technical Field

The invention relates to the technical field of boiler feed water treatment, in particular to a desalting and deoxidizing device and a desalting and deoxidizing method.

Background

Boiler feed water consists primarily of main condensate and make-up water, which contains a large amount of dissolved gases, such as oxygen, carbon dioxide, etc., which are present in the main condensate as well as in the make-up water. The gas dissolved in the water is more likely to chemically react with the metal at higher temperatures, causing corrosion of the metal surface. The most harmful of these are oxygen, which causes strong oxygen corrosion of thermal equipment and pipes, and carbon dioxide which aggravates this corrosion. In addition, all the non-condensable gas in water can also deteriorate heat transfer, increase thermal resistance and reduce the heat economy of the unit.

Therefore, it is necessary to remove oxygen from boiler feed water, and the common methods for removing oxygen from boiler feed water include chemical oxygen removal and physical oxygen removal. Chemical deoxygenation is a method of adding chemical agents into water to make dissolved oxygen in water produce chemical reaction with the dissolved oxygen to generate a non-corrosive stable compound, so that the purpose of deoxygenation is achieved. Physical oxygen removal is to remove dissolved oxygen and other gases in water by physical means, and has no residual substances in water, so that the oxygen removal method is widely applied to thermal power plants. The most common physical deoxygenation method applied in a thermal power plant is a thermal deoxygenation method which is low in price, and meanwhile, the deoxygenator is used as a mixed heater in a regenerative system and can heat feed water and improve the temperature of the feed water. In thermal power plants, the thermal oxygen removal process is the predominant oxygen removal process.

At present, the feed water of a boiler of a waste incineration power plant is generally 130 ℃, the feed water is sent into a coal economizer by a deaerator and then enters a boiler steam drum, the temperature of the feed water leaving the deaerator is 130 ℃, the pressure of the working environment of the deaerator is 0.27MPa, a heat source is 0.6MPa steam extraction steam from a steam turbine, the heat source is high-grade heat energy capable of pushing the steam turbine to do work, and the high-grade heat energy is used as the heat source of the heat source deaerator to cause energy waste. Practice shows that the deoxidization effect of the single deaerator is poor, and in production operation, because the deoxidization effect of the deaerator is poor, the mode operation of vacuum deoxidization and chemical auxiliary deoxidization is adopted, and although the deoxidization effect meets the operation requirement, the chemical residue added by the chemical auxiliary deoxidization has certain harm to a steam turbine, a boiler and a steam pipeline, and the effect is unstable. In addition, the proportion of the concentrated water generated by the traditional chemical water treatment process, such as a membrane method, an ion exchange method and the like, in raw water is 25-40%, and the part of concentrated water cannot be utilized, so that the waste of water resources is caused.

Disclosure of Invention

The present invention is based on the discovery and recognition by the inventors of the following facts and problems:

the working principle of the thermal deaerator is as follows: when the feed water in the deaerator is heated at constant pressure, the water evaporation process is continuously deepened along with the temperature rise, the partial pressure of the water vapor on the water surface is gradually increased, and the partial pressure of other gases dissolved in the water is gradually reduced. When the water is heated to the saturation temperature under the working pressure of the deaerator, the partial pressure of the water vapor is close to or equal to the full pressure of the gas on the water surface, the partial pressure of other gas on the water surface tends to zero at the moment, and the water does not contain other gas. Therefore, the deaerator is actually a deaerator, which not only removes oxygen, but also other gases, and also brings out a part of steam.

The evaporation temperature based on water is related to evaporation pressure, the higher the pressure is, the higher the evaporation temperature is, the evaporation temperature of water under atmospheric pressure (0.1MPa) is 100 ℃, and in an environment with lower pressure close to vacuum, the water can boil at the temperature lower than 100 ℃ to enable oxygen to escape, namely, the water can obtain satisfactory oxygen removal effect at lower temperature without consuming too much heat energy. For example, water under a pressure of 20kpa, corresponding to a saturated evaporation temperature of 60 ℃; water was supplied under 8kpa, corresponding to a saturated evaporation temperature of 41.5 ℃.

This application makes the feedwater evaporate in negative pressure, microthermal environment through making the environment of lower pressure in desalination deoxidization equipment, can reach better deoxidization effect, realizes the desalination simultaneously, avoids using relevant equipment, medicament of supplementary deoxidization technology of chemistry etc..

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art.

Therefore, the embodiment of the invention provides energy-saving desalting and deoxidizing equipment;

the embodiment of the invention also provides an energy-saving method for removing salt and oxygen.

The desalting and oxygen removing device comprises:

the first heat exchanger is provided with a first cavity, a first steam inlet, a first condensed water outlet, a first raw water inlet, a first steam outlet and a first vacuumizing port, each of the first raw water inlet, the first steam outlet and the first vacuumizing port is communicated with the first cavity, a first heat exchange tube is arranged in the first cavity, the first end part of the first heat exchange tube is communicated with the first steam inlet, and the second end part of the first heat exchange tube is communicated with the first condensed water outlet;

the second heat exchanger is provided with a second cavity, a second steam inlet, a second condensed water outlet, a second raw water inlet, a second steam outlet and a second vacuumizing port, each of the second raw water inlet, the second steam inlet and the second vacuumizing port is communicated with the second cavity, a second heat exchange tube is arranged in the second cavity, the first end part of the second heat exchange tube is communicated with the second steam inlet, the second end part of the second heat exchange tube is communicated with the second condensed water outlet, and the second steam inlet is communicated with the first steam outlet; and

the fifth heat exchanger is provided with a fifth cavity, a fifth steam inlet, a fifth condensed water outlet, a fifth cooling liquid inlet and a fifth cooling liquid outlet, each of the fifth cooling liquid inlet and the fifth cooling liquid outlet is communicated with the fifth cavity, a fifth heat exchange tube is arranged in the fifth cavity, the first end of the fifth heat exchange tube is communicated with the fifth steam inlet, the second end of the fifth heat exchanger is communicated with the fifth condensed water outlet, and the fifth steam inlet is connected with the second steam outlet.

The desalting and deoxidizing equipment disclosed by the embodiment of the invention has the advantages of high energy utilization rate, high water resource utilization rate, high safety of related equipment using the desalting and deoxidizing equipment and the like.

In some embodiments, the first chamber includes a first heat exchange chamber, a first steam chamber, and a first condensate chamber, the first heat exchange tube is provided in plurality, each of the first heat exchange tubes is disposed within the first heat exchange chamber, each of the first raw water inlet, the first steam outlet, and the first vacuuming port is in communication with the first heat exchange chamber, the first steam inlet is in communication with the first steam chamber, the first end of each of the first heat exchange tubes is in communication with the first steam chamber, the second end of each of the first heat exchange tubes is in communication with the first condensate chamber, and the first condensate outlet is in communication with the first condensate chamber;

the second chamber comprises a second heat exchange chamber, a second steam chamber and a second condensed water chamber, the second heat exchange tube is provided with a plurality of second heat exchange tubes, each of the second heat exchange tubes is arranged in the second heat exchange chamber, each of the second raw water inlet, the second steam outlet and the second vacuumizing port is communicated with the second heat exchange chamber, the second steam inlet is communicated with the second steam chamber, the first end of each of the second heat exchange tubes is communicated with the second steam chamber, the second end of each of the second heat exchange tubes is communicated with the second condensed water chamber, and the second condensed water outlet is communicated with the second condensed water chamber;

the fifth cavity comprises a fifth heat exchange cavity, a fifth steam cavity and a fifth condensate cavity, the fifth heat exchange tubes are multiple in number, each of the fifth heat exchange tubes is arranged in the fifth heat exchange cavity, each of the fifth cooling liquid inlet and the fifth cooling liquid outlet is communicated with the fifth heat exchange cavity, the fifth steam inlet is communicated with the fifth steam cavity, the first end of each of the fifth heat exchange tubes is communicated with the fifth steam cavity, the second end of each of the fifth heat exchange tubes is communicated with the fifth condensate cavity, and the fifth condensate outlet is communicated with the fifth condensate cavity.

In some embodiments, the first circulation pump has a first circulation pump inlet and a first circulation pump outlet, the first heat exchanger further has a first circulation water outlet, the first circulation water outlet is in communication with the first chamber, the first circulation pump inlet is in communication with the first circulation water outlet, the first circulation pump outlet is in communication with the first raw water inlet; and

the second circulating pump, the second circulating pump has second circulating pump import and second circulating pump export, the second heat exchanger further has the second circulating water export, the second circulating water export with second chamber intercommunication, the second circulating pump import with second circulating water export intercommunication, the second circulating pump export with second raw water import intercommunication.

In some embodiments, a first spray head is arranged in the first cavity, the first spray head is arranged above the first heat exchange pipe, and the first spray head is communicated with the first raw water inlet;

and a second spray head is arranged in the second cavity, the second spray head is arranged above the second heat exchange pipe, and the second spray head is communicated with the second raw water inlet.

In some embodiments, the third heat exchanger has a third chamber, a third steam inlet, a third condensed water outlet, a third condensed water inlet, and a third steam outlet and a third vacuum pumping port, each of the third condensed water inlet, the third steam inlet, and the third vacuum pumping port being in communication with the third chamber, a third heat exchange tube being disposed within the third chamber, a first end of the third heat exchange tube being in communication with the third steam inlet, a second end of the third heat exchange tube being in communication with the third condensed water outlet, wherein the third steam inlet is in communication with the second steam outlet, and the third condensed water inlet is in communication with the second condensed water outlet; and

the fourth heat exchanger is provided with a fourth cavity, a fourth steam inlet, a fourth condensed water outlet, a fourth condensed water inlet, a fourth steam outlet and a fourth vacuumizing port, each of the fourth condensed water inlet, the fourth steam inlet and the fourth vacuumizing port is communicated with the fourth cavity, a fourth heat exchange tube is arranged in the fourth cavity, the first end of the fourth heat exchange tube is communicated with the fourth steam inlet, the second end of the fourth heat exchange tube is communicated with the fourth condensed water outlet, the fourth steam inlet is communicated with the third steam outlet, the fourth condensed water inlet is communicated with the third condensed water outlet, and the fourth steam outlet is communicated with the fifth steam inlet.

In some embodiments, the third chamber comprises a third heat exchange chamber, a third steam chamber, and a third condensate chamber, the third heat exchange tube is provided in plurality, each of the third heat exchange tubes is disposed within the third heat exchange chamber, each of the third condensate inlet, the third steam outlet, and a third vacuum outlet is in communication with the third heat exchange chamber, the third steam inlet is in communication with the third steam chamber, the first end of each of the third heat exchange tubes is in communication with the third steam chamber, the third end of each of the third heat exchange tubes is in communication with the third condensate chamber, and the third condensate outlet is in communication with the third condensate chamber;

the fourth cavity comprises a fourth heat exchange cavity, a fourth steam cavity and a fourth condensate cavity, the fourth heat exchange tubes are multiple in number, each of the fourth heat exchange tubes is arranged in the fourth heat exchange cavity, each of the fourth steam outlet and the fourth vacuumizing port is communicated with the fourth heat exchange cavity, the fourth steam inlet is communicated with the fourth steam cavity, the fourth heat exchange tubes are multiple in number, the first end of each of the fourth heat exchange tubes is communicated with the fourth steam cavity, the fourth end of each of the fourth heat exchange tubes is communicated with the fourth condensate cavity, and the fourth condensate outlet is communicated with the fourth condensate cavity.

In some embodiments, the third circulation pump has a third circulation pump inlet and a third circulation pump outlet, the third heat exchanger further has a third circulation water outlet, the third circulation water outlet is in communication with the third chamber, the third circulation pump inlet is in communication with the third circulation water outlet, and the third circulation pump outlet is in communication with the third condensate inlet; and

the fourth circulating pump is provided with a fourth circulating pump inlet and a fourth circulating pump outlet, the fourth heat exchanger is further provided with a fourth circulating water outlet, the fourth circulating water outlet is communicated with the second cavity, the fourth circulating pump inlet is communicated with the fourth circulating water outlet, and the fourth circulating pump outlet is communicated with the fourth condensed water inlet.

In some embodiments, a third spray head is disposed in the third chamber, the third spray head is disposed above the third heat exchange tube, and the third spray head is in communication with the third condensed water inlet;

and a fourth spray head is arranged in the fourth cavity, the fourth spray head is arranged above the fourth heat exchange tube, and the fourth spray head is communicated with the fourth condensed water inlet.

The method for removing salt and oxygen implemented by the equipment comprises the following steps:

introducing first steam into a first heat exchange pipe of a first heat exchanger, introducing first raw water into a first cavity of the first heat exchanger, and vacuumizing the first cavity by using a first vacuumizing port so that the first raw water is heated by the first steam to obtain primary steam of the first raw water, and the first steam is cooled by the first raw water to obtain first condensed water;

introducing primary steam of first raw water into a second heat exchange pipe of a second heat exchanger, introducing second raw water into a second cavity of the second heat exchanger, and vacuumizing the second cavity by using a second vacuumizing port so that the second raw water is heated by the primary steam of the first raw water to obtain primary steam of the second raw water, and the primary steam of the first raw water is cooled by the second raw water to obtain primary condensed water of the first raw water;

and introducing primary steam of the second raw water into a fifth heat exchange pipe of a fifth heat exchanger, and introducing cooling liquid into a fifth cavity of the fifth heat exchanger so that the primary steam of the second raw water is cooled by the cooling liquid to obtain primary condensed water of the second raw water.

The desalting and deoxidizing method disclosed by the embodiment of the invention has the advantages of high energy utilization rate, high water resource utilization rate, high safety of related equipment using desalting and deoxidizing equipment and the like.

In some embodiments, the method for removing salt and oxygen further comprises the steps of: introducing primary steam of second raw water into a third heat exchange pipe of a third heat exchanger, introducing primary condensed water of the first raw water into a third cavity of the third heat exchanger, and vacuumizing the third cavity by using a third vacuumizing port so that the primary condensed water of the first raw water is heated by the primary steam of the second raw water to obtain secondary steam of the first raw water, and the primary steam of the second raw water is cooled by the primary condensed water of the first raw water to obtain primary condensed water of the second raw water;

introducing secondary steam of the first raw water into a fourth heat exchange pipe of a fourth heat exchanger, introducing primary condensed water of the second raw water into a fourth cavity of the fourth heat exchanger, and vacuumizing the fourth cavity by using a fourth vacuumizing port so that the primary condensed water of the second raw water is heated by the secondary steam of the first raw water to obtain the secondary steam of the second raw water, and the secondary steam of the first raw water is cooled by the primary condensed water of the second raw water to obtain the secondary condensed water of the first raw water;

and introducing secondary steam of the second raw water into a fifth heat exchange pipe of a fifth heat exchanger, and introducing cooling liquid into a fifth cavity of the fifth heat exchanger so that the secondary steam of the second raw water is cooled by the cooling liquid to obtain secondary condensed water of the second raw water.

Drawings

FIG. 1 is a schematic diagram of a desalination and oxygen removal apparatus according to one embodiment of the present invention.

Fig. 2 is a schematic structural view of the first heat exchanger and the second heat exchanger in fig. 1.

Fig. 3 is a schematic structural diagram of a fourth heat exchanger and a fifth heat exchanger in fig. 1.

Fig. 4 is a schematic structural view of the third heat exchanger in fig. 1.

Fig. 5 is a view along a-a of fig. 4.

Reference numerals are as follows: a desalination and oxygen removal device 100; a first heat exchanger 1; a first heat exchange pipe 101; a first end 1011; a second end 1012; a first heat exchange chamber 102; a first raw water inlet 1021; a first steam outlet 1022; a first steam chamber 103; a first steam inlet 1031; a first condensate chamber 104; a first condensed water outlet 1041; a first housing 105; a first partition 106; a second partition 107; a first vacuum port 108; a first drain port 109;

a second heat exchanger 2; a second heat exchange tube 201; a first end 2011; a second end 2012; a second heat exchange chamber 202; a second raw water inlet 2021; a second steam outlet 2022; a second steam chamber 203; a second steam inlet 2031; a second condensate chamber 204; a second condensed water outlet 2041; a second housing 205; a third partition 206; a fourth separator 207; a second vacuum port 208; a second drain 209;

a third heat exchanger 3; a third heat exchange tube 301; a first end 3011; a second end 3012; a third heat exchange chamber 302; a third condensate inlet port 3021; a third steam outlet 3022; a third vapor chamber 303; a third steam inlet 3031; a third condensate chamber 304; a third condensed water outlet 3041; a third housing 305; a fifth partition 306; a sixth partition plate 307; a third vacuum port 308; a third sewage drain 309;

a fourth heat exchanger 4; a fourth heat exchange pipe 401; a first end 4011; a second end 4012; a fourth heat exchange chamber 402; a fourth condensate inlet 4021; a fourth vapor outlet 4022; a fourth steam chamber 403; a fourth steam inlet 4041; a fourth condensate chamber 404; a fourth condensed water outlet 4041; a fourth housing 405; a seventh partition 406; an eighth bulkhead 407; a fourth vacuum port 408; a fourth sewage drain 409;

a fifth heat exchanger 5; a fifth heat exchange pipe 501; first end 5011; second end 5012; a fifth heat exchange chamber 502; a fifth coolant inlet 5021; a fifth coolant outlet 5022; a fifth steam chamber 503; a fifth vapor inlet 5031; a fifth condensate chamber 504; a fifth condensate outlet 5041; a fifth casing 505; a ninth partition plate 506; a tenth partition 507.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are illustrative and intended to explain the present invention and should not be construed as limiting the present invention.

As shown in fig. 1 to 5, the apparatus 100 for removing salt and oxygen according to the embodiment of the present invention includes a first heat exchanger 1, a second heat exchanger 2, and a fifth heat exchanger 5.

The first heat exchanger 1 has a first chamber, a first steam inlet 1031, a first condensed water outlet 1041, a first raw water inlet 1021, a first steam outlet 1022, and a first vacuuming port 108. Each of the first raw water inlet 1021, the first vapor outlet 1022 and the first vacuuming port 108 communicates with the first chamber. The first heat exchange pipe 101 is arranged in the first cavity, a first end 1011 of the first heat exchange pipe 101 is communicated with the first steam inlet 1031, and a second end 1012 of the first heat exchange pipe 101 is communicated with the first condensed water outlet 1041.

The second heat exchanger 2 has a second chamber, a second steam inlet 2031, a second condensed water outlet 2041, a second raw water inlet 2021, a second steam outlet 2022, and a second vacuum pumping port 208. Each of the second raw water inlet 2021, the second steam inlet 2031, and the second vacuum pumping port 208 communicates with the second chamber. A second heat exchange pipe 201 is arranged in the second cavity, a first end 2011 of the second heat exchange pipe 201 is communicated with the second steam inlet 2031, and a second end 2012 of the second heat exchange pipe 201 is communicated with the second condensed water outlet 2041. Wherein the second steam inlet 2031 is in communication with the first steam outlet 1022.

The fifth heat exchanger 5 has a fifth cavity, a fifth vapor inlet 5031, a fifth condensate outlet 5041, a fifth coolant inlet 5021, and a fifth coolant outlet 5022. Each of the fifth coolant inlet 5021 and the fifth coolant outlet 5022 is in communication with the fifth cavity. A fifth heat exchange tube 501 is disposed within the fifth chamber, a first end 5011 of the fifth heat exchange tube 501 communicating with the fifth vapor inlet 5031, and a second end 5012 of the fifth heat exchanger 5 communicating with the fifth condensate outlet 5041. Wherein the fifth vapor inlet 5031 is connected to the second vapor outlet 2022.

When the salt and oxygen removing apparatus 100 according to the embodiment of the present invention is used to remove oxygen from water, first steam is introduced into the first heat exchange tube 101 through the first steam inlet 1031 and the first end 1011 of the first heat exchange tube 101, first raw water is introduced into the first cavity of the first heat exchanger 1 through the first raw water inlet 1021 of the first heat exchanger 1, the first cavity is vacuumized by the first vacuuming port 108 so that the pressure in the first cavity is lower than the pressure in the first heat exchange tube 101, so that the first raw water and the first steam exchange heat, the first raw water is heated by the first steam to obtain primary steam (gaseous primary salt and oxygen removed water) of the first raw water, and then gases such as salt and oxygen in the first raw water are removed, and the first steam is cooled by the first raw water to obtain first condensed water.

Then, the primary steam of the first raw water is introduced into the second heat exchange tube 201 through the second steam inlet 2031 and the first end 2011 of the second heat exchange tube 201, the second raw water is introduced into the second cavity of the second heat exchanger 2 through the second raw water inlet 2021 of the second heat exchanger 2, the second cavity is vacuumized by the second vacuuming port 208 so that the pressure in the second cavity is smaller than the pressure in the second heat exchange tube 201, thus the primary steam of the first raw water exchanges heat with the second raw water, the second raw water is heated by the primary steam of the first raw water to obtain the primary steam of the second raw water (gaseous primary desalted and deoxygenated water), further the gases such as the salt and the oxygen in the second raw water are removed, and the primary steam of the first raw water is cooled by the second raw water to obtain the primary condensed water of the first raw water (liquid primary desalted and deoxygenated water).

Then, the primary vapor of the second raw water is introduced into the fifth heat exchange tube 501 through the fifth vapor inlet 5031 of the fifth heat exchanger 5 and the first end 5011 of the fifth heat exchange tube 501, and the coolant is introduced into the fifth chamber of the fifth heat exchanger 5 through the fifth coolant inlet 5021 of the fifth heat exchanger 5, so that the primary vapor of the second raw water exchanges heat with the coolant, and the primary vapor of the second raw water is cooled by the coolant to obtain primary condensed water (liquid primary condensed water) of the second raw water.

Because the second vacuum pumping port 208 is used for vacuumizing the second chamber, and the pressure of the second chamber is lower than the pressure in the second heat exchange tube 201, the second raw water in the second chamber can be evaporated at a lower temperature to become primary steam of the second raw water, and thus the primary steam of the first raw water entering the second heat exchange tube 201 can be steam with lower temperature and lower pressure. Because the first vacuum-pumping port 108 is utilized to vacuum the first cavity, and the pressure of the first cavity is lower than the pressure in the first heat exchange tube 101, the first raw water in the first cavity can be evaporated at a lower temperature to become primary steam of the first raw water, so that the first steam entering the first heat exchange tube 101 can be steam with lower temperature and lower pressure, and further low-grade heat energy with lower temperature and lower pressure can be used as a heat source (first steam) of the desalting and deoxidizing device 100, thereby reducing or even avoiding energy waste and saving energy. In addition, the desalination and oxygen removal device 100 of the embodiment of the invention does not use chemical agents, so that the damage of chemical agent residues to related devices and pipelines can be avoided.

In addition, because the in-process that first raw water becomes the primary steam of first raw water by the heating, impurity such as salt in the first raw water can stay in first intracavity for the primary steam of first raw water is gaseous desalination oxygen-removed water, the in-process that the second raw water becomes the primary steam of second raw water by the heating, impurity such as salt in the second raw water can stay in the second intracavity, make the primary steam of second raw water be gaseous desalination oxygen-removed water, therefore, the primary condensate water that obtains by the primary steam of first raw water and the primary steam cooling of second raw water is desalination salt-removed water once, this desalination water can be as boiler feedwater and let in the boiler. And the first raw water and the second raw water can be discharged by adopting the circulating water drainage of a waste incineration plant, the backwashing water of a water treatment station and the like, so that the sewage is recycled, and the utilization rate of water resources is improved.

Therefore, the desalination and oxygen removal equipment 100 according to the embodiment of the invention has the advantages of high energy utilization rate, high water resource utilization rate, high safety of related equipment using the desalination and oxygen removal equipment 100 and the like.

In some embodiments, the salt and oxygen removal apparatus 100 further comprises a third heat exchanger 3 and a fourth heat exchanger 4.

The third heat exchanger 3 has a third chamber, a third steam inlet 3031, a third condensate outlet 3041, a third condensate inlet 3021 and a third steam outlet 3022 and a third vacuum pumping port 308. Each of the third condensate inlet port 3021, the third steam inlet port 3031, and the third vacuum pumping port 308 communicates with the third chamber. The third heat exchange tube 301 is arranged in the third cavity, a first end portion 3011 of the third heat exchange tube 301 is communicated with a third steam inlet 3031, and a second end portion 3012 of the third heat exchange tube 301 is communicated with a third condensed water outlet 3041. The third steam inlet 3031 is communicated with the second steam outlet 2022, and the third condensed water inlet 3021 is communicated with the second condensed water outlet 2041.

The fourth heat exchanger 4 has a fourth chamber, a fourth steam inlet 4041, a fourth condensate outlet, a fourth condensate inlet 4021 and a fourth steam outlet 4022, and a fourth evacuation port 408. Each of the fourth condensate inlet 4021, the fourth steam inlet 4041, and the fourth vacuum port 408 communicates with the fourth chamber. A fourth heat exchange tube 401 is arranged in the fourth cavity, a first end portion 4011 of the fourth heat exchange tube 401 is communicated with a fourth steam inlet 4041, and a second end portion 4012 of the fourth heat exchange tube 401 is communicated with a fourth condensed water outlet. The fourth steam inlet 4041 is communicated with the third steam outlet 3022, the fourth condensed water inlet 4021 is communicated with the third condensed water outlet 3041, and the fourth steam outlet 4022 is communicated with the fifth steam inlet 5031.

Thus, when the desalination and oxygen removal apparatus 100 according to the embodiment of the present invention is used to remove oxygen and remove oxygen from water, the primary steam (gaseous primary desalination and oxygen removal water) of the second raw water and the primary condensed water (liquid primary desalination and oxygen removal water) of the first raw water obtained by the second heat exchanger 2 are subjected to the following steps:

the primary steam of the second raw water is introduced into the third heat exchange tube 301 through the third steam inlet 3031 of the third heat exchanger 3 and the first end 3011 of the third heat exchange tube 301, the primary condensed water of the first raw water is introduced into the third chamber through the third condensed water inlet 3021, the third chamber is vacuumized by the third vacuuming port so that the pressure in the third chamber is less than the pressure in the third heat exchange tube 301, and thus the primary steam of the second raw water exchanges heat with the primary condensed water of the first raw water, the primary condensed water of the first raw water is heated by the primary steam of the second raw water to obtain the secondary steam (gaseous secondary steam) of the first raw water, and further the gases such as salt and oxygen in the primary condensed water of the first raw water are removed, and the primary steam of the second raw water is cooled by the primary condensed water of the first raw water to obtain the primary condensed water (liquid primary condensed water) of the second raw water.

Then, the secondary steam of the first raw water is introduced into the fourth heat exchange tube 401 through a fourth steam inlet 4041 of the fourth heat exchanger 4 and the first end 4011 of the fourth heat exchange tube 401, the primary condensed water of the second raw water is introduced into the fourth cavity through a fourth condensed water inlet 4021, the fourth cavity is vacuumized by using a fourth vacuuming port so that the pressure in the fourth cavity is lower than the pressure in the fourth heat exchange tube 401, thereby the secondary steam of the first raw water and the primary condensed water of the second raw water exchange heat, the primary condensed water of the second raw water is heated by the secondary steam of the first raw water to obtain the secondary steam (gaseous secondary steam) of the second raw water, further, the primary condensed water of the second raw water is freed of gases such as salts and oxygen, and the secondary steam of the first raw water is cooled by the primary condensed water of the second raw water to obtain secondary condensed water (liquid secondary condensed water) of the first raw water.

Finally, the secondary steam of the second raw water is introduced into the fifth heat exchange tube 501 through the fifth steam inlet 5031 of the fifth heat exchanger 5 and the first end 5011 of the fifth heat exchange tube 501, and the coolant is introduced into the fifth chamber of the fifth heat exchanger 5 through the fifth coolant inlet 5021 of the fifth heat exchanger 5, so that the secondary steam of the second raw water exchanges heat with the coolant, and the secondary steam of the second raw water is cooled by the coolant to obtain secondary condensed water (liquid secondary condensed water) of the second raw water.

Since the fourth chamber is vacuumized by the fourth vacuum port 408, and the pressure of the fourth chamber is lower than the pressure in the fourth heat exchange tube 401, the primary condensed water of the second raw water in the fourth chamber can be evaporated at a lower temperature to become the secondary steam of the first raw water, and thus the secondary steam of the first raw water entering the fourth heat exchange tube 401 can be steam with a lower temperature and a lower pressure. Because the third vacuum pumping port 308 is utilized to vacuumize the third chamber, and the pressure of the third chamber is lower than the pressure in the third heat exchange tube 301, the primary condensed water of the first raw water in the third chamber can be evaporated at a lower temperature to become secondary steam of the first raw water, and thus, the primary steam of the second raw water entering the third heat exchange tube 301 can be steam with lower temperature and lower pressure. Similarly, the first steam entering the first heat exchange tube 101 may be steam with relatively low temperature and pressure, and then low-grade heat energy with relatively low temperature and relatively low pressure may be used as the heat source (first steam) of the desalination and oxygen removal apparatus 100.

In addition, because the process that the primary condensate of first raw water becomes the secondary steam of first raw water is heated, impurity such as salt in the primary condensate of first raw water can stay in the third intracavity, make the secondary steam of first raw water for salt is lower, gaseous form desalination deoxidization water, the process that the primary condensate of second raw water becomes the secondary steam of second raw water is heated, impurity such as salt in the primary condensate of second raw water can stay in the fourth intracavity, make the secondary steam of second raw water for salt is lower, gaseous form desalination deoxidization water, consequently, the secondary condensate that obtains by the secondary steam of first raw water and the secondary steam cooling of second raw water is secondary desalination water, this secondary desalination water can be as boiler feedwater and lets in the boiler. The quality of the desalted and deoxygenated water is improved, and the safety of relevant equipment using the desalted and deoxygenated equipment 100 is further improved.

Of course, in other embodiments, in order to further improve the quality of the desalted and deoxygenated water, one or more heat exchangers may be disposed between the fourth heat exchanger and the fifth heat exchanger, and the secondary condensed water may be evaporated and condensed multiple times by the heat exchanger disposed between the fourth heat exchanger and the fifth heat exchanger.

In some embodiments, the first chamber includes a first heat exchange chamber 102, a first steam chamber 103, and a first condensate chamber 104, the first heat exchange pipe 101 is provided in plurality, and each of the plurality of first heat exchange pipes 101 is disposed within the first heat exchange chamber 102. Each of the first raw water inlet 1021, the first steam outlet 1022 and the first vacuuming port 108 is communicated with the first heat exchange chamber 102, the first steam inlet 1031 is communicated with the first steam chamber 103, the first end 1011 of each of the plurality of first heat exchange tubes 101 is communicated with the first steam chamber 103, the second end 1012 of each of the plurality of first heat exchange tubes 101 is communicated with the first condensed water chamber 104, and the first condensed water outlet 1041 is communicated with the first condensed water chamber 104.

The second chamber includes a second heat exchange chamber 202, a second steam chamber 203, and a second condensate chamber 204, the second heat exchange pipe 201 is provided in plurality, and each of the plurality of second heat exchange pipes 201 is disposed in the second heat exchange chamber 202. Each of the second raw water inlet 2021, the second steam outlet 2022 and the second vacuuming port 208 is communicated with the second heat exchange chamber 202, the second steam inlet 2031 is communicated with the second steam chamber 203, the first end 2011 of each of the plurality of second heat exchange pipes 201 is communicated with the second steam chamber 203, the second end 2012 of each of the plurality of second heat exchange pipes 201 is communicated with the second condensed water chamber 204, and the second condensed water outlet 2041 is communicated with the second condensed water chamber 204.

The third chamber comprises a third heat exchange chamber 302, a third steam chamber 303 and a third condensed water chamber 304, the third heat exchange pipe 301 is provided in plurality, and each of the plurality of third heat exchange pipes 301 is arranged in the third heat exchange chamber 302. Each of the third condensed water inlet port 3021, the third steam outlet port 3022 and the third vacuum outlet port 308 communicates with the third heat exchange cavity 302, the third steam inlet port 3031 communicates with the third steam cavity 303, the first end 3011 of each of the plurality of third heat exchange tubes 301 communicates with the third steam cavity 303, the third end of each of the plurality of third heat exchange tubes 301 communicates with the third condensed water cavity 304, and the third condensed water outlet port 3041 communicates with the third condensed water cavity 304;

the fourth cavity comprises a fourth heat exchange cavity 402, a fourth steam cavity 403 and a fourth condensed water cavity, the fourth heat exchange tube 401 is provided with a plurality of tubes, and each of the plurality of fourth heat exchange tubes 401 is arranged in the fourth heat exchange cavity 402. Each of the fourth condensed water inlet 4021, the fourth steam outlet 4022 and the fourth vacuum pumping port 408 is in communication with the fourth heat exchange cavity 402, the fourth steam inlet 4041 is in communication with the fourth steam cavity 403, the first end 4011 of each of the plurality of fourth heat exchange tubes 401 is in communication with the fourth steam cavity 403, the fourth end of each of the plurality of fourth heat exchange tubes 401 is in communication with the fourth condensed water cavity, and the fourth condensed water outlet is in communication with the fourth condensed water cavity.

The fifth cavity comprises a fifth heat exchange cavity 502, a fifth steam cavity 503 and a fifth condensate cavity 504, the fifth heat exchange pipe 501 is provided with a plurality, and each of the plurality of fifth heat exchange pipes 501 is arranged in the fifth heat exchange cavity 502. Each of the fifth coolant inlet 5021 and the fifth coolant outlet 5022 is in communication with the fifth heat exchange cavity 502, the fifth vapor inlet 5031 is in communication with the fifth vapor cavity 503, the first end 5011 of each of the plurality of fifth heat exchange tubes 501 is in communication with the fifth vapor cavity 503, the second end 5012 of each of the plurality of fifth heat exchange tubes 501 is in communication with the fifth condensate cavity 504, and the fifth condensate outlet 5041 is in communication with the fifth condensate cavity 504.

For example, the first heat exchanger 1 includes a first casing 105, a first partition 106 and a second partition 107, the first partition 106 and the second partition 107 being provided at intervals in the extending direction of the first casing 105, and each of the plurality of first heat exchange tubes 101 extending in the extending direction of the first casing 105. A first steam chamber 103 is defined between the first casing 105 and the first partition 106, a first condensed water chamber 104 is defined between the first casing 105 and the second partition 107, and a first heat exchange chamber 102 is defined between the first casing 105, the first partition 106, and the second partition 107. A first end 1011 of each of the plurality of first heat exchange tubes 101 communicates with the first steam chamber 103 through the first partition 106, and a second end 1012 of each of the plurality of first heat exchange tubes 101 communicates with the first condensate chamber 104 through the second partition 107.

The second heat exchanger 2 includes a second shell 205, a third partition 206 and a fourth partition 207, the third partition 206 and the fourth partition 207 being disposed at intervals in the extending direction of the second shell 205, and each of the plurality of second heat exchange tubes 201 extending in the extending direction of the second shell 205. A second steam chamber 203 is defined between the second casing 205 and the third partition 206, a second condensate chamber 204 is defined between the second casing 205 and the fourth partition 207, and a second heat exchange chamber 202 is defined between the second casing 205, the third partition 206 and the fourth partition 207. A first end 2011 of each of the plurality of second heat exchange tubes 201 communicates with the second steam chamber 203 through the third partition 206, and a second end 2012 of each of the plurality of second heat exchange tubes 201 communicates with the second condensate chamber 204 through the fourth partition 207.

The third heat exchanger 3 includes a third shell 305, a fifth partition 306 and a sixth partition 307, the fifth partition 306 and the sixth partition 307 being disposed at a spacing in the extending direction of the third shell 305, and each of the plurality of third heat exchange tubes 301 extending in the extending direction of the third shell 305. A third steam chamber 303 is defined between the third shell 305 and the fifth partition 306, a third condensed water chamber 304 is defined between the third shell 305 and the sixth partition 307, and a third heat exchange chamber 302 is defined between the third shell 305, the fifth partition 306 and the sixth partition 307. The first end 3011 of each of the plurality of third heat exchange tubes 301 communicates with the third steam chamber 303 through the fifth partition 306, and the second end 3012 of each of the plurality of third heat exchange tubes 301 communicates with the third condensate chamber 304 through the sixth partition 307.

The fourth heat exchanger 4 includes a fourth casing 405, a seventh partition 406 and an eighth partition 407, the seventh partition 406 and the eighth partition 407 being disposed at intervals in the extending direction of the fourth casing 405, and each of the plurality of fourth heat exchange tubes 401 extends in the extending direction of the fourth casing 405. A fourth steam chamber 403 is defined between the fourth casing 405 and the seventh barrier 406, a fourth condensate chamber is defined between the fourth casing 405 and the eighth barrier 407, and a fourth heat exchange chamber 402 is defined between the fourth casing 405, the seventh barrier 406, and the eighth barrier 407. A first end 4011 of each of the plurality of fourth heat exchange tubes 401 communicates with the fourth steam chamber 403 through the seventh partition 406, and a second end 4012 of each of the plurality of fourth heat exchange tubes 401 communicates with the fourth condensate chamber through the eighth partition 407.

The fifth heat exchanger 5 includes a fifth casing 505, a ninth partition 506 and a tenth partition 507, the ninth partition 506 and the tenth partition 507 being provided at intervals in the extending direction of the fifth casing 505, and each of the plurality of fifth heat exchange tubes 501 extending in the extending direction of the fifth casing 505. A fifth steam chamber 503 is defined between the fifth casing 505 and the ninth partition 506, a fifth condensate chamber 504 is defined between the fifth casing 505 and the tenth partition 507, and a fifth heat exchange chamber 502 is defined between the fifth casing 505, the ninth partition 506 and the tenth partition 507. The first end 5011 of each of the plurality of fifth heat exchange pipes 501 communicates with the fifth steam chamber 503 through the ninth partition 506, and the fifth end of each of the plurality of fifth heat exchange pipes 501 communicates with the fifth condensate chamber 504 through the tenth partition 507.

For example, to make the technical solution of the present application easier to understand, the technical solution of the present application is further described below by taking as an example that the extending direction of the first housing 105 coincides with the left-right direction, where the left-right direction is shown in fig. 2.

The first heat exchanger 1 includes a first casing 105, a first partition 106 (left partition) and a second partition 107 (right partition), the first partition 106 and the second partition 107 being provided at a spacing in the left-right direction, each of the plurality of first heat exchange tubes 101 extending in the left-right direction. A first end 1011 (left end) of each of the plurality of first heat exchanging pipes 101 communicates with the first steam chamber 103 through the first partition 106, and a second end 1012 (right end) of each of the plurality of first heat exchanging pipes 101 communicates with the first condensed water chamber 104 through the second partition 107.

The second heat exchanger 2 includes a second casing 205, a third partition 206 (left partition), and a fourth partition 207 (right partition), the third partition 206 and the fourth partition 207 being provided at intervals in the left-right direction, each of the plurality of second heat exchange tubes 201 extending in the left-right direction. A first end 2011 (left end) of each of the plurality of second heat exchange tubes 201 communicates with the second steam chamber 203 through the third partition 206, and a second end 2012 (right end) of each of the plurality of second heat exchange tubes 201 communicates with the second condensate chamber 204 through the fourth partition 207.

The third heat exchanger 3 includes a third casing 305, a fifth partition 306 (left partition), and a sixth partition 307 (right partition), the fifth partition 306 and the sixth partition 307 being provided at a spacing in the left-right direction, each of the plurality of third heat exchange tubes 301 extending in the left-right direction. A first end 3011 (left end) of each of the plurality of third heat exchange tubes 301 is communicated with the third steam chamber 303 through the fifth partition 306, and a second end 3012 (right end) of each of the plurality of third heat exchange tubes 301 is communicated with the third condensate chamber 304 through the sixth partition 307.

The fourth heat exchanger 4 includes a fourth casing 405, a seventh partition 406 (left partition) and an eighth partition 407 (right partition), the seventh partition 406 and the eighth partition 407 being disposed at a spacing in the left-right direction, and each of the plurality of fourth heat exchange tubes 401 extends in the left-right direction. A first end 4011 (left end) of each of the plurality of fourth heat exchange tubes 401 passes through the seventh partition 406 to communicate with the fourth steam chamber 403, and a second end 4012 (right end) of each of the plurality of fourth heat exchange tubes 401 passes through the eighth partition 407 to communicate with the fourth condensate chamber.

A plurality of heat exchange tubes are arranged in each heat exchange cavity, so that the heat exchange area between each heat exchange tube and the corresponding heat exchange cavity can be effectively increased, the heat source utilization rate can be further improved, and further energy conservation can be further facilitated. In addition, steam firstly passes through the corresponding steam cavity and then enters the corresponding heat exchange tube from the steam cavity, so that the steam is conveniently introduced into the corresponding heat exchange tube.

The fifth heat exchanger 5 includes a fifth casing 505, a ninth partition 506 (left partition) and a tenth partition 507 (right partition), the ninth partition 506 and the tenth partition 507 being provided at a spacing in the left-right direction, each of the plurality of fifth heat exchange tubes 501 extending in the left-right direction. A first end 5011 (left end) of each of the plurality of fifth heat exchange pipes 501 communicates with the fifth steam chamber 503 through the ninth partition 506, and a second end 5012 (right end) of each of the plurality of fifth heat exchange pipes 501 communicates with the fifth condensate chamber 504 through the tenth partition 507.

A plurality of fifth heat exchange tubes 501 are arranged in the fifth heat exchange cavity 502, so that the heat exchange area between the fifth heat exchange tubes 501 and the fifth heat exchange cavity 502 can be effectively increased, the utilization rate of the cooling liquid can be further improved, and further energy conservation can be further facilitated. In addition, the secondary steam of the second raw water firstly passes through the fifth steam cavity 503 and then enters the fifth heat exchange tube 501 through the fifth steam cavity 503, so that the secondary steam of the second raw water is conveniently introduced into the fifth heat exchange tube 501.

In some embodiments, the apparatus 100 further comprises a first circulation pump, a second circulation pump, a third circulation pump, and a fourth circulation pump.

The first circulating pump has first circulating pump import and first circulating pump and exports, and first heat exchanger 1 further has first circulating water outlet, first circulating water outlet and first chamber intercommunication, first circulating pump import and first circulating water outlet intercommunication, first circulating pump export and first raw water import 1021 intercommunication.

The second circulating pump has second circulating pump import and second circulating pump and exports, and second heat exchanger 2 further has the second circulating water export, second circulating water export and second chamber intercommunication, second circulating pump import and second circulating water export intercommunication, second circulating pump export and second raw water import 2021 intercommunication.

The third circulating pump has a third circulating pump inlet and a third circulating pump outlet, the third heat exchanger 3 further has a third circulating water outlet, the third circulating water outlet is communicated with the third cavity, the third circulating pump inlet is communicated with the third circulating water outlet, and the third circulating pump outlet is communicated with the third condensate inlet 3021.

The fourth circulating pump has the import of fourth circulating pump and the export of fourth circulating pump, and fourth heat exchanger 4 further has the fourth circulating water export, fourth circulating water export and second chamber intercommunication, the import of fourth circulating pump and fourth circulating water export intercommunication, and the export of fourth circulating pump and fourth condensate inlet 4021 intercommunication.

From this, utilize first circulating pump to continue to let in first intracavity with the first raw water of first intracavity non-evaporation carry out the desalination deoxidization, utilize the second circulating pump to continue to let in the second intracavity with the second raw water of second intracavity non-evaporation carry out the desalination deoxidization, utilize the third circulating pump to continue to let in the third chamber with the primary condensate water of the first raw water of third intracavity non-evaporation carry out the desalination deoxidization, utilize the fourth circulating pump to continue to let in the fourth intracavity with the primary condensate water conservation of the second raw water of fourth intracavity non-evaporation carry out the desalination deoxidization, be favorable to further improving water resource utilization.

In some embodiments, the first heat exchanger 1 further has a first drain 109, and the first drain 109 is connected to the second chamber. When impurity such as salt content is more in the aquatic of first intracavity, can discharge the water of first intracavity through first drain 109 to clear up first chamber.

Preferably, the first drain 109 and the first circulating water outlet are switchably connected to the second chamber. From this, when utilizing desalination deoxidization equipment 100 to carry out the desalination deoxidization to water, first circulating water outlet links to each other with the second chamber, when needs clear up desalination deoxidization equipment 100, and first drain 109 links to each other with the second chamber.

Preferably, the apparatus 100 further comprises a first control valve having a first valve inlet, a first valve outlet and a second valve outlet. The first chamber is provided with a first mounting hole connected with the first chamber, the first control valve is mounted on the first mounting hole, the inlet of the first valve is connected with the first chamber, the outlet of the first valve forms a first circulating water outlet, and the outlet of the second valve forms a first drain opening 109. When the impurities and salt in the water in the first cavity are less, the first valve outlet is opened, the second valve outlet is closed, and the water in the first cavity enters the first circulating pump through the first valve outlet. When the impurities and salt in the water in the first cavity are more than a few percent to form concentrated water, the first valve outlet is closed, the second valve outlet is opened, the water in the first cavity enters the first drain outlet 109 through the second valve outlet to drain the concentrated water, and after the concentrated water is drained, the first valve outlet is opened and the second valve outlet is closed.

In some embodiments, the second heat exchanger 2 further has a second drain 209, and the second drain 209 is connected to the second chamber. When impurity such as the aquatic salinity of second intracavity is more, can discharge the water of second intracavity through second drain 209 to clear up the second chamber.

Preferably, the second drain 209 and the second circulating water outlet are switchably connected to the second chamber. From this, when utilizing desalination deoxidization equipment 100 to carry out the desalination deoxidization to water, the second circulating water export links to each other with the second chamber, and when needs clear up desalination deoxidization equipment 100, second drain 209 links to each other with the second chamber.

Preferably, the apparatus 100 further comprises a second control valve having a second valve inlet, a third valve outlet, and a fourth valve outlet. The second chamber is provided with a second mounting hole connected with the second chamber, the second control valve is mounted on the second mounting hole, the inlet of the second valve is connected with the second chamber, the outlet of the third valve forms a second circulating water outlet, and the outlet of the fourth valve forms a second sewage draining outlet 209. When the impurities and salt in the water in the second cavity are less, the outlet of the third valve is opened, the outlet of the fourth valve is closed, and the water in the second cavity enters the second circulating pump through the outlet of the third valve. When more impurities and salt in the water in the second cavity form concentrated water, the outlet of the third valve is closed, the outlet of the fourth valve is opened, the water in the second cavity enters the second sewage draining outlet 209 through the outlet of the fourth valve to drain the concentrated water, and the outlet of the third valve is opened and the outlet of the fourth valve is closed after the concentrated water is drained.

In some embodiments, the third heat exchanger 3 further has a third sewage discharge outlet 309, the third sewage discharge outlet 309 being connected to the second chamber. When impurities such as salt in water in the third cavity are more, water in the third cavity can be discharged through the third sewage discharge port 309, and therefore the third cavity is cleaned.

Preferably, a third sewage drain 309 and a third circulating water outlet are switchably connected to the second chamber. Therefore, when the desalination and oxygen removal equipment 100 is used for conducting desalination and oxygen removal on water, the third circulating water outlet is connected with the second cavity, and when the desalination and oxygen removal equipment 100 needs to be cleaned, the third sewage outlet 309 is connected with the second cavity.

Preferably, the salt and oxygen removal apparatus 100 further comprises a third control valve having a third valve inlet, a fifth valve outlet, and a sixth valve outlet. And a third mounting hole connected with the third cavity is formed in the third cavity, a third control valve is mounted on the third mounting hole, an inlet of the third valve is connected with the third cavity, a fifth valve outlet forms a third circulating water outlet, and a sixth valve outlet forms a third sewage draining outlet 309. When the impurities and salt in the water in the third cavity are less, the outlet of the fifth valve is opened, the outlet of the sixth valve is closed, and the water in the third cavity enters the third circulating pump through the outlet of the fifth valve. When more impurities and more salts in the water in the third cavity form concentrated water, the fifth valve outlet is closed, the sixth valve outlet is opened, the water in the third cavity enters the third sewage draining outlet 309 through the sixth valve outlet to drain the concentrated water, and the fifth valve outlet is opened and the sixth valve outlet is closed after the concentrated water is drained.

In some embodiments, the fourth heat exchanger 4 further has a fourth waste outlet 409, and the fourth waste outlet 409 is connected to the second chamber. When impurities such as salinity in the water in the fourth cavity are more, the water in the fourth cavity can be discharged through the fourth sewage outlet 409, so that the fourth cavity is cleaned.

Preferably, the fourth drain outlet 409 and the fourth circulating water outlet are switchably connected to the second chamber. From this, when utilizing desalination deoxidization equipment 100 to carry out the desalination deoxidization to water, the fourth circulating water export links to each other with the second chamber, and when needs clear up desalination deoxidization equipment 100, fourth drain 409 links to each other with the second chamber.

Preferably, the salt and oxygen removal apparatus 100 further comprises a fourth control valve having a fourth valve inlet, a seventh valve outlet, and an eighth valve outlet. And a third mounting hole connected with the fourth cavity is formed in the fourth cavity, a fourth control valve is mounted on the third mounting hole, an inlet of the fourth control valve is connected with the fourth cavity, a seventh valve outlet forms a third circulating water outlet, and an eighth valve outlet forms a third sewage draining outlet 309. When the impurities and the salt in the water in the fourth cavity are less, the seventh valve outlet is opened, the eighth valve outlet is closed, and the water in the fourth cavity enters the third circulating pump through the seventh valve outlet. When more impurities and salt in the water in the fourth cavity form concentrated water, the seventh valve outlet is closed, the eighth valve outlet is opened, the water in the fourth cavity enters the third sewage draining outlet 309 through the eighth valve outlet to drain the concentrated water, and the seventh valve outlet is opened and the eighth valve outlet is closed after the concentrated water is drained.

In some embodiments, a first spray head is disposed in the first chamber, the first spray head is disposed above the first heat exchange pipe 101, and the first spray head is communicated with the first raw water inlet 1021. From this, utilize first shower nozzle to spout first raw water into first intracavity, not only be favorable to improving the heat transfer area between first raw water and the first steam, be favorable to improving the velocity of flow of first raw water moreover to be favorable to improving the heat exchange efficiency of first raw water and first steam, and then be favorable to improving the utilization ratio of first steam (heat source), be favorable to further energy saving.

In some embodiments, a second spray head is disposed in the second chamber, the second spray head is disposed above the second heat exchange pipe 201, and the second spray head is communicated with the second raw water inlet 2021. Therefore, the second raw water is sprayed into the second cavity by the second spray nozzle, so that the heat exchange area between the primary steam of the second raw water and the primary steam of the first raw water is improved, the flow rate of the second raw water is improved, the heat exchange efficiency of the primary steam of the second raw water and the primary steam of the first raw water is improved, the utilization rate of the primary steam of the first raw water is improved, and further energy conservation is facilitated.

In some embodiments, a third spray head is disposed in the third chamber, the third spray head is disposed above the third heat exchange tube 301, and the third spray head is communicated with the third condensed water inlet 3021. From this, utilize the third shower nozzle to spout the primary condensate of first raw water into in the third chamber, not only be favorable to improving the heat transfer area between the primary condensate of first raw water and the primary steam of second raw water, be favorable to improving the velocity of flow of the primary condensate of first raw water moreover to be favorable to improving the heat exchange efficiency of the primary condensate of first raw water and the primary steam of second raw water, and then be favorable to improving the utilization ratio of the primary steam of second raw water, be favorable to further energy saving.

In some embodiments, a fourth nozzle is disposed in the fourth chamber, the fourth nozzle is disposed above the fourth heat exchange pipe 401, and the fourth nozzle is communicated with the fourth raw water inlet. From this, utilize the fourth shower nozzle to spout the primary condensate of second raw water into the fourth intracavity, not only be favorable to improving the heat transfer area between the secondary steam of the primary condensate of second raw water and first raw water, be favorable to improving the velocity of flow of the primary condensate of second raw water moreover to be favorable to improving the heat exchange efficiency of the secondary steam of the primary condensate of second raw water and first raw water, and then be favorable to improving the utilization ratio of the secondary steam of a raw water, be favorable to further energy saving.

Preferably, each of the first heat exchanging tube 101, the second heat exchanging tube 201, the third heat exchanging tube 301, the fourth heat exchanging tube 401 and the fifth heat exchanging tube 501 is made of a metal material. The metal material has good heat transfer performance, and is favorable for further improving the heat exchange efficiency of each heat exchanger.

In other embodiments, the first heat exchange tube, the second heat exchange tube, the third heat exchange tube, the fourth heat exchange tube and the fifth heat exchange tube may be made of titanium alloy or stainless steel. To cope with a wider range of usage scenarios.

Preferably, the first shell 105, the second shell 205, the third shell 305, the fourth shell 405 and the fifth shell 505 are cylinders with a diameter of 2.5m, and the first shell 105, the second shell 205, the third shell 305, the fourth shell 405 and the fifth shell 505 are all 2m long. Therefore, the first heat exchanger 1, the second heat exchanger 2, the third heat exchanger 3, the fourth heat exchanger 4 and the fifth heat exchanger 5 can have sufficient heat exchange space, and the heat exchange efficiency of the first heat exchanger 1, the second heat exchanger 2, the third heat exchanger 3, the fourth heat exchanger 4 and the fifth heat exchanger 5 can be improved.

Preferably, the first heat exchanger 1, the second heat exchanger 2, the third heat exchanger 3 and the fourth heat exchanger 4 have similar structures and identical manufacturing processes, so that unified manufacturing is facilitated, the manufacturing time of equipment is saved, and the cost is saved.

Taking a refuse incineration power plant with 400t/d of incineration scale and adopting medium-temperature and medium-pressure steam parameters (4.0MPa and 400 ℃) as an example, the water supply quantity sent into a boiler through a deaerator is 40 t/h.

The waste steam generated by the boiler blow-off steam, the steam seal heater, the hydrophobic flash tank and the like of the power generation system is about 2t/h, the 2t waste steam is used as a 100 heat source of the desalting and deoxidizing device, the waste steam is 65 ℃ saturated steam, through heat balance calculation, the heat of the heat source can heat 39t/h of 20 ℃ raw water into 42 ℃ boiler feed water, and the desalting and deoxidizing water after 39t/h treatment and 2t/h of heat source steam condensate water can meet the boiler circulating water replenishing requirement considering water loss and heat exchange loss in each link.

Alloy heat exchange tubes with the inner diameter of 0.025m are used in the desalting and deoxidizing equipment 100, the steam flow rate is 15m/s, 350 heat exchange tubes are needed by calculation, 7 rows are arranged, the average number of each row is 50, the interval between the heat exchange tubes is 0.05m, and a cylinder with the diameter of 2.5m is selected as an external cylinder; the length of each heat exchanger is 2m, and the total length of the equipment is 10 m.

Referring to fig. 1 to 5, a method for removing salt and oxygen by using the apparatus 100 for removing salt and oxygen of an embodiment of the present invention is described in detail by taking 1.5t/h and 65 ℃ saturated steam as the first steam as an example:

introducing first steam (65 ℃) serving as a heat source of the first heat exchanger 1 into a first heat exchange tube 101 of the first heat exchanger 1, introducing first raw water into a first cavity of the first heat exchanger 1, exchanging heat between the first steam and the first raw water, cooling the first steam into first condensed water, wherein the first condensed water comes from a boiler, is desalted and deoxygenated water, and can be directly sent back to a boiler steam pocket through a condensed water pump and a feed water pump; the first raw water is heated to be primary steam of the first raw water. The temperature difference between the first steam and the first raw water is 3-5 ℃, and the evaporation temperature of the first raw water outside the first heat exchange tube 101 is about 60-62 ℃.

The primary steam of the first raw water is introduced into the second heat exchange tube 201 of the second heat exchanger 2 as a heat source of the second heat exchanger 2, the second raw water is introduced into the second cavity of the second heat exchanger 2, the primary steam of the first raw water exchanges heat with the second raw water, the primary steam of the first raw water is cooled to be primary condensed water of the first raw water, and the second raw water is heated to be primary steam of the second raw water. The primary steam of the first raw water and the second raw water have a temperature difference of 3 ℃ to 5 ℃, and the evaporation temperature of the second raw water outside the second heat exchange tube 201 is about 55 ℃ to 57 ℃.

The primary steam of the second raw water is introduced into a third heat exchange tube 301 of the third heat exchanger 3 as a heat source of the third heat exchanger 3, primary condensed water of the first raw water is introduced into a third cavity of the third heat exchanger 3, the primary steam of the second raw water exchanges heat with the primary condensed water of the first raw water, the primary steam of the second raw water is cooled to be the primary condensed water of the second raw water, and the primary condensed water of the first raw water is heated to be secondary steam of the first raw water. The temperature difference between the primary steam of the second raw water and the primary condensed water of the first raw water is 3-5 ℃, and the evaporation temperature of the primary condensed water of the first raw water outside the third heat exchange pipe 301 is about 50-52 ℃.

The secondary steam of the first raw water is introduced into a fourth heat exchange tube 401 of the fourth heat exchanger 4 as a heat source of the fourth heat exchanger 4, the primary condensed water of the second raw water is introduced into a fourth cavity of the fourth heat exchanger 4, the secondary steam of the first raw water exchanges heat with the primary condensed water of the second raw water, the secondary steam of the first raw water is cooled into the secondary condensed water of the first raw water, and the primary condensed water of the second raw water is heated into the secondary steam of the second raw water. The temperature difference between the secondary steam of the first raw water and the primary condensed water of the second raw water is 3-5 ℃, and the evaporation temperature of the primary condensed water of the second raw water outside the fourth heat exchange pipe 401 is about 45-47 ℃.

The secondary steam of the first raw water is introduced into a fifth heat exchange tube 501 of the fifth heat exchanger 5, the coolant serving as the coolant of the fifth heat exchanger 5 is introduced into a fifth cavity of the fifth heat exchanger 5, the secondary steam of the first raw water exchanges heat with the coolant, and the secondary steam of the first raw water is cooled to be secondary condensed water (42 ℃) of the first raw water. The secondary condensed water of the first raw water and the primary condensed water of the second raw water are both desalted and deoxidized water, and the secondary condensed water of the first raw water and the primary condensed water of the second raw water are mixed and then are sent into a boiler through a boiler feed pump.

The desalination and oxygen removal device 100 according to an embodiment of the present invention has the following features:

(1) the steam used as the heat source in the first heat exchanger 1 of the low-temperature desalting and oxygen removing device 100 can be low-pressure exhaust steam in a thermodynamic cycle of a waste incineration power plant, the exhaust steam can be steam generated by a boiler blow-down flash tank, steam generated by a hydrophobic flash tank, steam in a steam seal heater and the like, and the temperature of the exhaust steam is not lower than 65 ℃. The dead steam is a low-grade heat source, and is beneficial to improving the energy utilization rate.

(2) In the low-temperature desalting and deoxidizing process, only the first heat exchanger 1 needs to provide a heat source from the outside, and the heat source steam of the second heat exchanger, the third heat exchanger and the fourth heat exchanger 4 is the steam generated by raw water to be treated in the previous heat exchanger.

(3) The first, second, third and fourth heat exchangers 4 are continuously evacuated by an external vacuum pump, the internal ambient pressure is maintained at about 20kPa, 16kPa, 12kPa, 8kPa, respectively, and the evaporation temperatures of the corresponding water are about 60 ℃, 55 ℃, 50 ℃, 41.5 ℃, respectively.

(4) The bottom of each heat exchanger is provided with a circulating pump, so that water to be treated is continuously heated, and the utilization rate of water resources is favorably improved.

(5) The steam dead steam as a heat source and the water which is finally subjected to secondary desalting and deoxidization are used as boiler feed water and are sent back to the waste incineration boiler, so that the utilization rate of water resources is improved.

(6) The concentrated water (raw water) containing impurities such as salt and the like in the low-temperature desalting and deoxidizing device 100 is discharged out of the device through a concentrated water outlet at the bottom of the device, so that the device can be cleaned.

In addition, according to the desalination and oxygen removal equipment 100 provided by the embodiment of the invention, raw water can be circulated and evaporated for multiple times in the equipment, and finally, the proportion of the produced concentrated water is less than 10%, and the proportion of the produced desalination and oxygen removal water is more than 90%.

The method for removing salt and oxygen according to the embodiment of the invention comprises the following steps:

introducing first steam into a first heat exchange tube 101 of a first heat exchanger 1, introducing first raw water into a first cavity of the first heat exchanger 1, and vacuumizing the first cavity by using a first vacuumizing port 108, so that the first raw water is heated by the first steam to obtain primary steam of the first raw water, and the first steam is cooled by the first raw water to obtain first condensed water;

introducing primary steam of the first raw water into a second heat exchange tube 201 of a second heat exchanger 2, introducing second raw water into a second cavity of the second heat exchanger 2, and vacuumizing the second cavity by using a second vacuumizing port 208, so that the second raw water is heated by the primary steam of the first raw water to obtain primary steam of the second raw water, and the primary steam of the first raw water is cooled by the second raw water to obtain primary condensate of the first raw water;

the primary steam of the second raw water is introduced into the fifth heat exchange tube 501 of the fifth heat exchanger 5, and a cooling liquid is introduced into the fifth chamber of the fifth heat exchanger 5, so that the primary steam of the second raw water is cooled by the cooling liquid to obtain primary condensed water of the second raw water.

The desalting and deoxidizing device 100 disclosed by the embodiment of the invention has the advantages of high energy utilization rate, high water resource utilization rate, high safety of related devices using the desalting and deoxidizing device 100 and the like.

In some embodiments, a method for removing salt and oxygen according to embodiments of the present invention further comprises the steps of:

introducing primary steam of the second raw water into a third heat exchange tube 301 of a third heat exchanger 3, introducing primary condensed water of the first raw water into a third cavity of the third heat exchanger 3, and vacuumizing the third cavity by using a third vacuumizing port 308, so that the primary condensed water of the first raw water is heated by the primary steam of the second raw water to obtain secondary steam of the first raw water, and the primary steam of the second raw water is cooled by the primary condensed water of the first raw water to obtain primary condensed water of the second raw water;

introducing secondary steam of the first raw water into a fourth heat exchange tube 401 of a fourth heat exchanger 4, introducing primary condensed water of the second raw water into a fourth cavity of the fourth heat exchanger 4, and vacuumizing the fourth cavity by using a fourth vacuumizing port 408, so that the primary condensed water of the second raw water is heated by the secondary steam of the first raw water to obtain secondary steam of the second raw water, and the secondary steam of the first raw water is cooled by the primary condensed water of the second raw water to obtain secondary condensed water of the first raw water;

the secondary steam of the second raw water is introduced into the fifth heat exchange tube 501 of the fifth heat exchanger 5, and the cooling liquid is introduced into the fifth chamber of the fifth heat exchanger 5, so that the secondary steam of the second raw water is cooled by the cooling liquid to obtain the secondary condensed water of the second raw water.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, but are not intended to indicate or imply that the device or element so referred to must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be construed as limiting the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; may be mechanically coupled, may be electrically coupled or may be in communication with each other; may be directly connected or indirectly connected through intervening media, and may be internal to the two elements or may be in an interactive relationship with the two elements unless expressly defined otherwise. The specific meanings of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

In the present invention, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the second feature or the first and second features may be indirectly contacting each other through intervening media. Also, a first feature "on," "above," and "over" a second feature may be directly on or obliquely above the second feature, or simply mean that the first feature is at a higher level than the second feature. A first feature "under," "beneath," and "under" a second feature may be directly under or obliquely under the second feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the present disclosure, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples" and the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. A desalination and oxygen removal apparatus comprising:

the second heat exchanger is provided with a second cavity, a second steam inlet, a second condensed water outlet, a second raw water inlet, a second steam outlet and a second vacuumizing port, each of the second raw water inlet, the second steam inlet and the second vacuumizing port is communicated with the second cavity, a second heat exchange tube is arranged in the second cavity, the first end part of the second heat exchange tube is communicated with the second steam inlet, the second end part of the second heat exchange tube is communicated with the second condensed water outlet, and the second steam inlet is communicated with the first steam outlet;

a third heat exchanger having a third chamber, a third steam inlet, a third condensed water outlet, a third condensed water inlet, a third steam outlet, and a third vacuum outlet, each of the third condensed water inlet, the third steam inlet, and the third vacuum outlet being in communication with the third chamber, a third heat exchange tube being disposed in the third chamber, a first end of the third heat exchange tube being in communication with the third steam inlet, a second end of the third heat exchange tube being in communication with the third condensed water outlet, wherein the third steam inlet is in communication with the second steam outlet, and the third condensed water inlet is in communication with the second condensed water outlet;

a fourth heat exchanger, wherein the fourth heat exchanger is provided with a fourth cavity, a fourth steam inlet, a fourth condensed water outlet, a fourth condensed water inlet, a fourth steam outlet and a fourth vacuumizing port, each of the fourth condensed water inlet, the fourth steam inlet and the fourth vacuumizing port is communicated with the fourth cavity, a fourth heat exchange tube is arranged in the fourth cavity, the first end of the fourth heat exchange tube is communicated with the fourth steam inlet, the second end of the fourth heat exchange tube is communicated with the fourth condensed water outlet, the fourth steam inlet is communicated with the third steam outlet, the fourth condensed water inlet is communicated with the third condensed water outlet, and the fourth steam outlet is communicated with a fifth steam inlet; and

the fifth heat exchanger is provided with a fifth cavity, a fifth steam inlet, a fifth condensed water outlet, a fifth cooling liquid inlet and a fifth cooling liquid outlet, each of the fifth cooling liquid inlet and the fifth cooling liquid outlet is communicated with the fifth cavity, a fifth heat exchange tube is arranged in the fifth cavity, the first end of the fifth heat exchange tube is communicated with the fifth steam inlet, the second end of the fifth heat exchanger is communicated with the fifth condensed water outlet, and the fifth steam inlet is connected with the fourth steam outlet.

2. The apparatus according to claim 1, wherein the first chamber comprises a first heat exchange chamber, a first steam chamber and a first condensed water chamber, the first heat exchange tube is provided in plurality, each of the first heat exchange tubes is disposed in the first heat exchange chamber, each of the first raw water inlet, the first steam outlet and the first vacuum outlet is communicated with the first heat exchange chamber, the first steam inlet is communicated with the first steam chamber, the first end of each of the first heat exchange tubes is communicated with the first steam chamber, the second end of each of the first heat exchange tubes is communicated with the first condensed water chamber, and the first condensed water outlet is communicated with the first condensed water chamber;

the second cavity comprises a second heat exchange cavity, a second steam cavity and a second condensed water cavity, the second heat exchange tubes are provided with a plurality of second heat exchange tubes, each of the second heat exchange tubes is arranged in the second heat exchange cavity, each of the second raw water inlet, the second steam outlet and the second vacuumizing port is communicated with the second heat exchange cavity, the second steam inlet is communicated with the second steam cavity, the first end of each of the second heat exchange tubes is communicated with the second steam cavity, the second end of each of the second heat exchange tubes is communicated with the second condensed water cavity, and the second condensed water outlet is communicated with the second condensed water cavity;

3. The apparatus according to claim 1, further comprising:

the first circulating pump is provided with a first circulating pump inlet and a first circulating pump outlet, the first heat exchanger is further provided with a first circulating water outlet, the first circulating water outlet is communicated with the first cavity, the first circulating pump inlet is communicated with the first circulating water outlet, and the first circulating pump outlet is communicated with the first raw water inlet; and

the second circulating pump, the second circulating pump has second circulating pump import and second circulating pump export, the second heat exchanger further has the second circulating water export, the second circulating water export with the second chamber intercommunication, the second circulating pump import with second circulating water export intercommunication, the second circulating pump export with the raw water import of second intercommunication.

4. The apparatus according to claim 1, wherein a first spray head is arranged in the first chamber, the first spray head is arranged above the first heat exchange pipe, and the first spray head is communicated with the first raw water inlet;

5. The apparatus according to claim 1, wherein the third chamber comprises a third heat exchange chamber, a third steam chamber and a third condensate chamber, the third heat exchange tube is provided in plurality, each of the third heat exchange tubes is disposed in the third heat exchange chamber, each of the third condensate inlet, the third steam outlet and a third vacuum outlet is in communication with the third heat exchange chamber, the third steam inlet is in communication with the third steam chamber, the first end of each of the third heat exchange tubes is in communication with the third steam chamber, the second end of each of the third heat exchange tubes is in communication with the third condensate chamber, and the third condensate outlet is in communication with the third condensate chamber;

the fourth cavity comprises a fourth heat exchange cavity, a fourth steam cavity and a fourth condensate cavity, the fourth heat exchange tubes are multiple in number, each of the fourth heat exchange tubes is arranged in the fourth heat exchange cavity, each of the fourth steam outlet and the fourth vacuumizing port is communicated with the fourth heat exchange cavity, the fourth steam inlet is communicated with the fourth steam cavity, the fourth heat exchange tubes are multiple in number, the first end of each of the fourth heat exchange tubes is communicated with the fourth steam cavity, the second end of each of the fourth heat exchange tubes is communicated with the fourth condensate cavity, and the fourth condensate outlet is communicated with the fourth condensate cavity.

6. The apparatus according to claim 1, further comprising:

a third circulating pump having a third circulating pump inlet and a third circulating pump outlet, the third heat exchanger further having a third circulating water outlet, the third circulating water outlet being in communication with the third chamber, the third circulating pump inlet being in communication with the third circulating water outlet, the third circulating pump outlet being in communication with the third condensate inlet; and

the fourth circulating pump is provided with a fourth circulating pump inlet and a fourth circulating pump outlet, the fourth heat exchanger is further provided with a fourth circulating water outlet, the fourth circulating water outlet is communicated with the second cavity, the fourth circulating pump inlet is communicated with the fourth circulating water outlet, and the fourth circulating pump outlet is communicated with the fourth condensate water inlet.

7. The apparatus according to claim 1, wherein a third spray head is arranged in the third chamber, the third spray head is arranged above the third heat exchange pipe, and the third spray head is communicated with the third condensed water inlet;

8. A method of salt and oxygen removal using the apparatus of any one of claims 1 to 7, comprising the steps of:

introducing primary steam of the first raw water into a second heat exchange pipe of a second heat exchanger, introducing second raw water into a second cavity of the second heat exchanger, and vacuumizing the second cavity by using a second vacuumizing port so that the second raw water is heated by the primary steam of the first raw water to obtain primary steam of the second raw water, and the primary steam of the first raw water is cooled by the second raw water to obtain primary condensate of the first raw water;

introducing primary steam of second raw water into a third heat exchange pipe of a third heat exchanger, introducing primary condensed water of the first raw water into a third cavity of the third heat exchanger, and vacuumizing the third cavity by using a third vacuumizing port so that the primary condensed water of the first raw water is heated by the primary steam of the second raw water to obtain secondary steam of the first raw water, and the primary steam of the second raw water is cooled by the primary condensed water of the first raw water to obtain primary condensed water of the second raw water;

and introducing secondary steam of the second raw water into a fifth heat exchange pipe of the fifth heat exchanger, and introducing cooling liquid into a fifth cavity of the fifth heat exchanger so that the secondary steam of the second raw water is cooled by the cooling liquid to obtain secondary condensed water of the second raw water.