阅读说明：本技术 舰船冷却海水淡化系统及方法 (Ship cooling seawater desalination system and method ) 是由 邹士洋 张建平 伍俊荣 丁冰泉 章建程 李亿光 刘丽英 王学辉 左旭 于 2021-01-26 设计创作，主要内容包括：本发明提供了一种舰船冷却海水淡化系统及方法。该系统包括：过滤部、加热器、增压输送部、蒸馏分离器、冷凝器以及抽真空器,其中,过滤部与冷却系统的冷却水出口相连接,用于对换热后的冷却海水进行过滤预处理得到过滤冷却海水,加热器对过滤冷却海水进行加热得到待淡化海水,增压输送部对待淡化海水进行增压并按照预设海水流量输送,蒸馏分离器对增压后的待淡化海水进行真空蒸馏分离处理得到浓海水和水蒸汽,冷凝器对水蒸汽进行真空冷凝处理得到淡水,抽真空器用于对蒸汽腔和蒸汽凝结腔分别抽真空。(The invention provides a ship cooling seawater desalination system and a ship cooling seawater desalination method. The system comprises: the device comprises a filtering part, a heater, a pressurizing and conveying part, a distillation separator, a condenser and a vacuum extractor, wherein the filtering part is connected with a cooling water outlet of a cooling system and used for filtering and preprocessing cooled seawater after heat exchange to obtain filtered and cooled seawater, the heater heats the filtered and cooled seawater to obtain seawater to be desalinated, the pressurizing and conveying part pressurizes the seawater to be desalinated and conveys the seawater according to a preset seawater flow, the distillation separator performs vacuum distillation and separation processing on the pressurized seawater to be desalinated to obtain concentrated seawater and water vapor, the condenser performs vacuum condensation processing on the water vapor to obtain fresh water, and the vacuum extractor is used for respectively vacuumizing a steam cavity and a steam condensation cavity.)

1. The utility model provides a naval vessel cooling sea water desalination is connected with the cooling system of naval vessel for carry out desalination to the cooling sea water after this cooling system exhaust heat transfer and obtain the fresh water that can directly drink, its characterized in that includes:

a filtering part, a heater, a pressurizing and conveying part, a distillation separator, a condenser and a vacuum-pumping device,

wherein the filtering part is connected with a cooling water outlet of the cooling system and is used for filtering and pretreating the cooled seawater after heat exchange to obtain filtered and cooled seawater,

the heater receives the filtered and cooled seawater and heats the filtered and cooled seawater to obtain seawater with preset water temperature as seawater to be desalinated,

the pressurizing and conveying part pressurizes the seawater to be desalinated and conveys the seawater according to the preset seawater flow,

the distillation separator receives the pressurized seawater to be desalinated, and performs vacuum distillation separation treatment on the seawater to be desalinated to obtain concentrated seawater and water vapor,

the condenser receives the water vapor and carries out vacuum condensation treatment on the water vapor to obtain the fresh water,

the vacuum extractor is communicated with the steam cavity of the distillation separator and the steam condensation cavity of the condenser respectively and is used for vacuumizing the steam cavity and the steam condensation cavity respectively.

2. The ship cooling seawater desalination system of claim 1, further comprising:

a concentrated seawater reflux part for refluxing the concentrated seawater into the heater,

wherein the concentrated seawater reflux part comprises a reflux pipe and a reflux valve arranged on the reflux pipe,

and two end parts of the return pipe are respectively connected with a seawater return outlet of the distillation separator and a seawater return inlet of the heater.

3. The ship cooling seawater desalination system of claim 1, wherein:

wherein the preset water temperature is 60-80 ℃,

the preset seawater flow is 35-40L/min,

the vacuum degrees in the steam cavity and the steam condensation cavity are both 0.08-0.09 Mpa.

4. The ship cooling seawater desalination system of claim 1, wherein:

wherein the filter part comprises a medium filter and an ultrafiltration filter which are connected with each other,

the water inlet of the medium filter is connected with the cooling water outlet,

and the water outlet of the ultrafiltration filter is connected with the water inlet of the heater.

5. The ship cooling seawater desalination system of claim 1, wherein:

wherein, the heater is a constant temperature heater.

6. The ship cooling seawater desalination system of claim 1, wherein:

wherein the pressurizing and conveying part comprises a pressurizing and conveying pipe, and a pressurizing and conveying pump, a liquid regulating valve and a liquid flowmeter which are arranged on the pressurizing and conveying pipe in sequence,

and two end parts of the pressurizing conveying pipe are respectively connected with the water outlet of the heater and the seawater inlet of the distillation separator.

7. The ship cooling seawater desalination system of claim 1, wherein:

wherein the distillation separator comprises a membrane distillation module comprising a plurality of membrane support tubes,

each membrane supporting tube is provided with a tube body and a microporous hydrophobic membrane wrapped on the outer surface of the tube body, and the microporous hydrophobic membrane is a NACE membrane.

8. The ship cooling seawater desalination system of claim 1, wherein:

wherein the condenser is provided with a condenser shell and a heat exchange tube arranged in the condenser shell,

one end of the heat exchange tube is used for receiving raw seawater which is outside the ship and used as condensate, and the other end of the heat exchange tube is used as a condensate outlet for discharging the condensate after heat exchange.

9. The ship cooling seawater desalination system of claim 1, further comprising:

a seawater introducing part for introducing the cooled seawater after heat exchange into the filtering part under pressure,

wherein the seawater introducing part comprises a water conduit and a water pump arranged on the water conduit,

one end part of the water conduit is connected with the cooling water outlet, and the other end part of the water conduit is connected with the filtering part.

10. A ship cooling seawater desalination method is used for desalinating heat-exchanged cooling seawater discharged by a ship cooling system to obtain directly drinkable fresh water, and is characterized by comprising the following steps:

filtering and pretreating the cooled seawater subjected to heat exchange to obtain filtered and cooled seawater;

heating the filtered and cooled seawater to obtain seawater with preset water temperature as seawater to be desalinated;

pressurizing the seawater to be desalinated and conveying the seawater according to a preset seawater flow;

carrying out vacuum distillation separation treatment on the pressurized seawater to be desalinated to obtain concentrated seawater and water vapor;

and carrying out vacuum condensation treatment on the water vapor to obtain the fresh water.

Technical Field

The invention belongs to the technical field of seawater desalination, and particularly relates to a ship cooling seawater desalination system and method.

Background

The ship is an important device for offshore national defense strength, the energy consumption of a power device is huge, but the contradiction between self-sustaining force prolonging and limited fuel transportation capacity is highlighted day by day, and under the background of rapid increase of long-distance voyage execution tasks and gradual reduction of petroleum fuels, the waste heat of the ship is recycled, so that the fuel utilization rate is improved at will. A large number of diesel engine heat balance analyses show that: the effective utilization heat energy of the marine diesel engine only accounts for 45-50%, and the energy loss after being taken away by hot water exceeds 20%. The waste heat temperature of the cooling water is high, the recovery value is high, and other waste heat such as heat dissipation of equipment such as a diesel engine body and an air cooler is low in energy grade and high in recovery difficulty. Therefore, the efficient recycling of the waste heat of the cooling water becomes a key breakthrough point of the ship waste heat utilization technology.

The cooling system is one of important systems for ensuring safe and reliable operation of the ship power device, and generally, the high-temperature part of the ship power device is cooled by fresh water, then the cooled fresh water is cooled by seawater, and the low-temperature part is directly cooled by seawater. The cooling fresh water temperature of the cylinder sleeve of the marine diesel engine reaches 70-90 ℃, but the cooling seawater temperature is only 40-50 ℃, and the cylinder sleeve also belongs to a low-grade heat source, is difficult to recover and directly discharges to cause a large amount of heat energy loss of the diesel engine. Exploration of a ship cooling water waste heat utilization way has important significance for promoting energy conservation and emission reduction of ships.

The seawater desalination is carried out by utilizing the cooling seawater for cooling and heat exchanging the ship power device, the energy consumption of the seawater desalination device is reduced, and the energy use efficiency and the open sea self-sustaining force of the ship can be effectively improved. Scholars at home and abroad develop some researches on the sea water desalination technology by using the waste heat of cooling water of ships. Hung et al propose that the seawater is heated to saturation temperature by waste heat, then fresh water is produced by a throttling and depressurizing method, a multi-effect seawater evaporation mathematical model is established, and the influence of key operation parameters on the seawater yield is calculated. Liu Gawu and the like establish a theoretical model of a single-effect vacuum distillation seawater desalination system driven by cooling water of a cylinder sleeve of a main engine of a ship, and calculate and analyze the influence rule of the temperature, the flow, the evaporation pressure and the seawater temperature of the cooling water on the water yield. The canadum and the like design a fresh water-air conditioner composite function system taking water/water vapor as a single heating medium according to the principle of energy gradient recycling of marine diesel engines, and have a plurality of functions of heating/refrigerating, fresh water preparation and the like. However, the researches only carry out theoretical calculation through a mathematical model, and a seawater desalination system and a method for desalinating ship cooling seawater to obtain directly drinkable fresh water are not available so far.

Disclosure of Invention

The present invention has been made to solve the above problems, and an object of the present invention is to provide a system and a method for desalinating cooling seawater discharged from a cooling system of a ship after heat exchange, which can desalinate the cooling seawater to obtain fresh water that can be directly drunk, and which can fully utilize low-grade waste heat in the cooling seawater, and have the advantages of low operation energy consumption, simple structure, large water flux, and purer quality of the obtained fresh water.

In order to achieve the purpose, the invention adopts the following technical scheme:

< first embodiment >

The invention provides a ship cooling seawater desalination system, which is connected with a ship cooling system and used for desalinating heat-exchanged cooling seawater discharged by the cooling system to obtain directly drinkable fresh water, and has the characteristics that: a filtering part, a heater, a pressurizing and conveying part, a distillation separator, a condenser and a vacuum extractor, wherein the filtering part is connected with a cooling water outlet of a cooling system, used for filtering and pretreating the cooled seawater after heat exchange to obtain filtered and cooled seawater, the heater receives the filtered and cooled seawater, and heating the filtered and cooled seawater to obtain seawater with preset water temperature as seawater to be desalinated, pressurizing the seawater to be desalinated by a pressurizing conveying part and conveying the seawater according to preset seawater flow, receiving the pressurized seawater to be desalinated by a distillation separator, and the seawater to be desalinated is subjected to vacuum distillation separation treatment to obtain concentrated seawater and water vapor, the condenser receives the water vapor, and the water vapor is subjected to vacuum condensation treatment to obtain fresh water, and the vacuumizing device is respectively communicated with the steam cavity of the distillation separator and the steam condensation cavity of the condenser and is used for respectively vacuumizing the steam cavity and the steam condensation cavity.

The ship cooling seawater desalination system provided by the invention can also have the following characteristics: further comprising: and the concentrated seawater backflow part is used for returning concentrated seawater into the heater, wherein the concentrated seawater backflow part comprises a backflow pipe and a backflow valve arranged on the backflow pipe, and two ends of the backflow pipe are respectively connected with a seawater backflow outlet of the distillation separator and a seawater backflow inlet of the heater.

The ship cooling seawater desalination system provided by the invention can also have the following characteristics: wherein the preset water temperature is 60-80 ℃, the preset seawater flow is 35-40L/min, and the vacuum degrees in the steam cavity and the steam condensation cavity are both 0.08-0.09 Mpa.

The ship cooling seawater desalination system provided by the invention can also have the following characteristics: wherein, the filter part comprises a medium filter and an ultrafiltration filter which are connected with each other, the water inlet of the medium filter is used for being connected with the cooling water outlet, and the water outlet of the ultrafiltration filter is connected with the water inlet of the heater.

The ship cooling seawater desalination system provided by the invention can also have the following characteristics: wherein, the heater is a constant temperature heater.

The ship cooling seawater desalination system provided by the invention can also have the following characteristics: wherein, pressure boost conveying part contains the pressure boost conveyer pipe and sets gradually booster pump, liquid control valve and the liquid flowmeter on this pressure boost conveyer pipe, and two tip of pressure boost conveyer pipe are connected with the delivery port of heater and the sea water import of distillation separator respectively.

The ship cooling seawater desalination system provided by the invention can also have the following characteristics: wherein the distillation separator comprises a membrane distillation assembly comprising a plurality of membrane support tubes, each membrane support tube having a tube body and a microporous hydrophobic membrane wrapped around an outer surface of the tube body, the microporous hydrophobic membrane being a NACE membrane.

The ship cooling seawater desalination system provided by the invention can also have the following characteristics: the condenser is provided with a condenser shell and a heat exchange tube arranged in the condenser shell, one end of the heat exchange tube is used for receiving raw seawater which is outside the ship and used as condensate, and the other end of the heat exchange tube is used as a condensate outlet for discharging the condensate after heat exchange.

The ship cooling seawater desalination system provided by the invention can also have the following characteristics: further comprising: the seawater introducing part is used for introducing the cooled seawater subjected to heat exchange into the filtering part in a pressurizing manner, wherein the seawater introducing part comprises a water conduit and a water pump arranged on the water conduit, one end part of the water conduit is used for being connected with the cooling water outlet, and the other end part of the water conduit is connected with the filtering part.

< scheme two >

The invention also provides a ship cooling seawater desalination method, which is used for desalinating the cooling seawater discharged by the cooling system of the ship after heat exchange to obtain fresh water capable of being directly drunk, and has the characteristics that the method comprises the following steps:

filtering and pretreating the cooled seawater subjected to heat exchange to obtain filtered and cooled seawater;

heating the filtered and cooled seawater to obtain seawater with preset water temperature as seawater to be desalinated;

pressurizing the seawater to be desalinated and conveying the seawater according to a preset seawater flow;

carrying out vacuum distillation separation treatment on the pressurized seawater to be desalinated to obtain concentrated seawater and water vapor;

and carrying out vacuum condensation treatment on the water vapor to obtain fresh water.

Action and Effect of the invention

According to the ship cooling seawater desalination system and the ship cooling seawater desalination method, the filtering part is connected with the cooling water outlet of the cooling system, the heat-exchanged cooling seawater can be subjected to filtering pretreatment to obtain the filtering cooling seawater, the heater can be used for filtering the cooling seawater to heat the filtering cooling seawater to obtain the seawater with the preset water temperature as the seawater to be desalinated, the pressurizing conveying part is used for pressurizing the seawater to be desalinated and conveying the seawater according to the preset seawater flow, the distillation separator can be used for carrying out vacuum distillation separation treatment on the pressurized seawater to be desalinated to obtain concentrated seawater and water vapor, and the condenser can be used for carrying out vacuum condensation treatment on the water vapor to obtain fresh water; and the structure is simple, the water production flux is large, and the quality of the obtained fresh water is purer.

Drawings

FIG. 1 is a schematic diagram of a ship cooling seawater desalination system in an embodiment of the present invention.

Detailed Description

The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings, so as to fully understand the objects, the features and the effects of the system and the method for desalinating seawater by cooling a ship.

< example >

FIG. 1 is a schematic diagram of a ship cooling seawater desalination system in an embodiment of the present invention.

As shown in fig. 1, in this embodiment, a ship cooling seawater desalination system 100 is installed on a ship and is connected to a cooling system of the ship and a compressed air generator, respectively, for desalinating heat-exchanged cooling seawater discharged from the cooling system to obtain directly drinkable fresh water. The ship cooling seawater desalination system 100 includes a seawater introduction part 10, a filtration part 20, a heater 30, a pressurization transportation part 40, a distillation separator 50, a condenser 60, a vacuum extractor 70, and a concentrated seawater reflux part 80.

As shown in fig. 1, the seawater intake section 10 is used for pressurizing and feeding the cooled seawater after heat exchange discharged from the cooling system into the filtering section 20, and includes a water conduit 11 and a water pump 12.

One end of the water conduit 11 is connected to a cooling water outlet 200 of the cooling system, and the other end is connected to an inlet of a medium filter 21 in the filter part 20.

The water diversion pump 12 is arranged on the water diversion pipe 11 and used for pressurizing and conveying the cooled seawater after heat exchange.

As shown in fig. 1, the filtering unit 20 is used for filtering and pre-treating the cooled seawater after heat exchange to obtain filtered and cooled seawater, and includes a medium filter 21 and an ultra-filtration filter 22 connected to each other.

The media filter 21 serves as a primary filter for removing large-particle impurities from the seawater. The inlet of the medium filter 21 is connected to and communicated with the other end of the water conduit 11 so as to receive the heat-exchanged cooling seawater discharged from the cooling water outlet 200.

The ultrafiltration filter 22 serves as a secondary filter for removing fine suspended particles from the seawater. The water inlet of the ultrafiltration filter 22 is connected with the water outlet of the medium filter 21 through a water delivery pipe.

As shown in fig. 1, the heater 30 is an electric heating pipe heating type constant temperature heater, and is configured to receive the filtered and cooled seawater obtained by the filtering unit 20, and heat the filtered and cooled seawater to obtain seawater with a preset water temperature meeting the requirement of distillation and separation as seawater to be desalinated. In this embodiment, the preset water temperature is 60-80 ℃.

The top of the heater 30 is provided with a water inlet and a seawater return inlet. A water outlet is arranged at the lower part of the side wall of the heater 30, and a thermometer 31 is arranged at the water outlet and used for monitoring the temperature of the seawater to be desalinated in real time.

As shown in fig. 1, the pressurizing and conveying part 40 is used for pressurizing the seawater to be desalinated and conveying the seawater to the distillation separator 50 according to a preset seawater flow, so that the driving force of water vapor penetrating through the microporous hydrophobic membrane is effectively increased, and the water production efficiency of the system is improved; in this embodiment, the preset seawater flow rate is 35-40L/min. The pressure-increasing conveying unit 40 includes a pressure-increasing conveying pipe 41, a pressure-increasing conveying pump 42, a liquid regulating valve 43, and a liquid flow meter 44, and the pressure-increasing conveying pump 42, the liquid regulating valve 43, and the liquid flow meter 44 are sequentially provided on the pressure-increasing conveying pipe 41.

Both ends of the pressurizing delivery pipe 41 are connected to the water outlet of the heater 30 and the seawater inlet of the distillation separator 50, respectively.

The booster pump 42 is used for boosting and conveying the seawater to be desalinated.

The liquid regulating valve 43 is used for regulating the flow rate of the seawater in the pressurizing delivery pipe 41 to reach the preset seawater flow rate.

The liquid flow meter 44 is used to monitor the flow rate of seawater in the booster duct 41 in real time.

As shown in fig. 1, the distillation separator 50 is configured to receive the pressurized seawater to be desalinated, and perform vacuum distillation separation on the seawater to be desalinated to obtain concentrated seawater and water vapor. The distillation separator 50 includes a distiller shell 51, a membrane distillation assembly 52, and a water distribution plate (not shown).

The bottom of the distiller's housing 51 is provided with a seawater inlet connected to one end of the pressurizing delivery pipe 41. The top of the distiller shell 51 is provided with a steam outlet, and the upper part of the side wall is provided with a seawater return outlet.

Membrane distillation assembly 52 is disposed within distiller housing 51, having a mounting plate 521 and a plurality of membrane support tubes 522.

The periphery of the mounting plate 521 is hermetically connected to the sidewall of the distiller case 51 and is located above the seawater backflow outlet, so as to divide the inner space of the distiller case 51 into a water distribution chamber 501 and a steam chamber 502 which are arranged in a vertical manner.

A plurality of membrane support tubes 522 are spaced apart from each other on the lower surface of the mounting plate 521 and extend downward, and the upper ports of all the membrane support tubes 522 communicate with the steam chamber 502.

Each membrane support tube 522 has a tube body and a microporous hydrophobic membrane wrapped around the outer surface of the tube body.

The pipe main body is a round pipe with a plurality of through holes on the pipe wall.

The microporous hydrophobic membrane is a Nano-structure High Charge Density Electrolyte membrane (NACE membrane for short), seawater to be desalinated entering the water distribution cavity 501 is subjected to water-vapor separation on the surface of the NACE membrane, and water vapor enters the pipe main body through the NACE membrane and is collected into the steam cavity 502. In this example, the NACE membrane has a thickness of 12mm, an average pore diameter of 0.15 μm, a porosity of 79%, and a contact angle of 150.1 °.

The water distribution plate is fixedly arranged in the distillation shell 51 and positioned below the membrane distillation assembly 52, is communicated with the seawater inlet, and is used for uniformly spraying seawater to be desalinated onto the membrane distillation assembly 52.

As shown in fig. 1, the condenser 60 is used for receiving water vapor and performing vacuum condensation treatment on the water vapor to obtain fresh water which can be directly drunk. The condenser 60 includes a condenser case 61 and a heat exchange pipe 62.

The condenser case 61 is provided at the top thereof with a steam inlet connected and communicated with the steam outlet of the distillation separator 50 through a steam pipe. The bottom of the condenser shell 61 is provided with a fresh water outlet which is connected with the ship fresh water tank 300 through a fresh water pipe, and the fresh water pipe is provided with a fresh water discharge valve 611. The upper portion of the side wall of the condenser case 61 is provided with a vent hole, and a vent valve 612 is provided at the vent hole.

The heat exchange pipe 62 is a spiral pipe fixedly disposed at an upper middle portion within the condenser case 61 such that a space between the heat exchange pipe 62 and the upper middle portion of the condenser case 61 forms a steam condensation chamber 601 of the condenser 60 and a lower space of the condenser case 61 forms a fresh water collecting chamber 602. The water vapor entering the vapor condensation chamber 601 from the vapor inlet condenses as water droplets on the outer surface of the heat exchange tube 62 and the adjacent area, and collects in the fresh water collection chamber 602.

The heat exchange tube 62 has a lower end portion extended outside the condenser case 61 to form a condensate inlet 621 and an upper end portion extended outside the condenser case 61 to form a condensate outlet 622. In this embodiment, the raw seawater outside the vessel is used as the condensate for the condenser 60, i.e. the condensate inlet 621 receives the raw seawater outside the vessel.

As shown in fig. 1, the vacuum extractor 70 communicates with the steam condensation chamber 601 of the condenser 60 through a pressure pipe, and further communicates with the distillation chamber 502 of the distillation separator 50 through a steam pipe, so that the steam condensation chamber 601 and the steam chamber 502 can be respectively evacuated. The pressure pipe is provided with a vacuum meter 71 for monitoring the vacuum degree in the steam cavity 502 and the steam condensation cavity 601 in real time. In this embodiment, the vacuum levels in the steam chamber 502 and the steam condensation chamber 601 are both 0.08-0.09 MPa.

As shown in fig. 1, the rich seawater reflux unit 80 is for refluxing the rich seawater obtained by the distillation separator 50 into the heater 30, and includes a reflux pipe 81 and a reflux valve 82.

Both ends of the return pipe 81 are connected and communicated with the seawater return outlet of the distillation separator 50 and the seawater return inlet of the heater 30, respectively.

A return valve 82 is provided on the return pipe 81.

In this embodiment, a seawater discharge valve 83 is further provided on a portion of the return pipe 81 between the return valve 82 and the distillation separator 50.

In this embodiment, the seawater desalination method for desalinating heat-exchanged cooling seawater discharged from a cooling system of a ship by using the ship cooling seawater desalination system 100 includes the following steps:

step S1 is to start the priming pump 12 and to pressurize the heat-exchanged cooling seawater discharged from the cooling system and feed it into the filtering part 20.

In step S2, the filtering unit 20 performs a filtering pretreatment on the heat-exchanged cooling seawater to obtain filtered cooling seawater.

Step S3, the heater 30 heats the filtered and cooled seawater to obtain seawater with a preset water temperature as the seawater to be desalinated.

In step S4, the pressurizing and conveying unit 40 pressurizes the seawater to be desalinated and conveys the seawater according to a preset seawater flow rate.

Step S5, the distillation separator 50 performs vacuum distillation separation treatment on the pressurized seawater to be desalinated to obtain concentrated seawater and water vapor.

Step S6, the condenser 60 performs vacuum condensation on the water vapor to obtain fresh water, and the fresh water is collected into the fresh water collection cavity 602; at the same time, the return valve 82 is opened, and the concentrated seawater is returned to the heater 30 through the return pipe 81.

Step S7, the vent valve 612 and the fresh water discharge valve 611 are opened in sequence, and the fresh water in the fresh water collecting chamber 602 is automatically discharged into the ship fresh water compartment 300.

Effects and effects of the embodiments

According to the ship cooling seawater desalination system and the ship cooling seawater desalination method related to the embodiment, the filtering part is connected with the cooling water outlet of the cooling system, the heat-exchanged cooling seawater can be subjected to filtering pretreatment to obtain the filtering cooling seawater, the heater can be used for filtering the cooling seawater to heat the filtering cooling seawater to obtain the seawater with the preset water temperature as the seawater to be desalinated, the pressurizing conveying part is used for pressurizing the seawater to be desalinated and conveying the seawater according to the preset seawater flow, the distillation separator can be used for carrying out vacuum distillation separation treatment on the pressurized seawater to be desalinated to obtain concentrated seawater and water vapor, and the condenser can be used for carrying out vacuum condensation treatment on the water vapor to obtain fresh water; and the structure is simple, the water production flux is large, and the quality of the obtained fresh water is purer.

In addition, since the concentrated seawater reflux unit is provided, the concentrated seawater can be refluxed into the heater to heat and distill the concentrated brine again, and the fresh water production rate can be further improved.

In addition, because the preset water temperature is 60-80 ℃, the preset seawater flow is 35-40L/min, and the vacuum degrees in the steam cavity and the steam condensation cavity are both 0.08-0.09Mpa, the whole system is in a better operation state, thereby saving energy, ensuring the smooth operation of distillation separation and condensation, and further improving the productivity and the water quality of fresh water.

In addition, because the filter part is provided with the medium filter and the ultrafiltration filter which are connected with each other, colloidal suspended matters and macromolecular organic matters in seawater can be intercepted, and the pollution of a microporous hydrophobic membrane in the distillation separator is effectively slowed down.

In addition, because the heater adopts the constant temperature heater, can heat up the cooling sea water secondary to suitable temperature, the energy consumption of effective control cooling sea water secondary intensification, the energy saving.

In addition, because the pressurizing conveying part is provided with the pressurizing conveying pipe, and the pressurizing conveying pump, the liquid regulating valve and the liquid flowmeter which are sequentially arranged on the pressurizing conveying pipe, two end parts of the pressurizing conveying pipe are respectively connected with the water outlet of the heater and the seawater inlet of the distillation separator, the structure is simple, and the operation is convenient; moreover, the material is easy to purchase in the market, and the manufacturing cost is further reduced.

In addition, because the distillation separator comprises a membrane distillation component which comprises a plurality of membrane supporting pipes, each membrane supporting pipe is provided with a pipe body and a microporous hydrophobic membrane wrapped on the outer surface of the pipe body, and the microporous hydrophobic membrane is a NACE membrane, the separation effect is good; moreover, the structure is simple, the purchase is easy on the market, and the manufacturing cost is further reduced.

In addition, because the condenser is provided with a condenser shell and a heat exchange tube arranged in the condenser shell, one end part of the heat exchange tube can receive the original seawater which is outside the ship and is used as condensate, and the other end part of the heat exchange tube is used as a condensate outlet to discharge the condensate after heat exchange, the original seawater outside the ship is fully utilized, and the energy is saved.

In addition, because the vacuum extractor is communicated with the steam condenser of the condenser and further connected with the distillation cavity of the distillation separator, the steam pressure difference at two sides of the microporous hydrophobic membrane is effectively increased, the driving force of steam penetrating through the microporous hydrophobic membrane is improved, and therefore the fresh water production efficiency is improved.

In addition, because the seawater introducing part is arranged, the cooled seawater after heat exchange can be pressurized and sent into the filtering part, the pressure difference of the seawater on two sides of the filtering medium in the filter can be increased, and the filtering effect of the seawater is further improved.

The above embodiments are preferred examples of the present invention, and are not intended to limit the scope of the present invention.