阅读说明：本技术 基于多孔介质的正向渗透-电动盐差能高效连续发电装置 (Forward osmosis-electric salt difference energy efficient continuous power generation device based on porous medium ) 是由 焦艳梅 安逸 宋林辉 张慧玲 王会 高秀敏 蒋关希曦 马勃龙 蔡茂文 黄孟巍 张 于 2020-12-08 设计创作，主要内容包括：本发明公开了一种基于多孔介质的正向渗透-电动盐差能高效连续发电装置,包括淡水源(1)、电动模块(2)、正向渗透模块(5)和咸水源(9),其特征在于：所述的正向渗透模块(5)包括正向渗透单元(14),正向渗透单元(14)包括半透膜制成的淡水膜通道(15)和咸水膜通道(16),淡水膜通道(15)和咸水膜通道(16)交错层叠形成平面渗透结构,淡水膜通道(15)的淡水进口(151)接收淡水源(1)输出的、经过电动模块(2)中的二维微纳米膜通道(12)后的淡水,咸水膜通道(16)的咸水进口(161)接收咸水源(9)输出的咸水。本发明的发电装置的系统传质效率高、系统能量转化效率高、系统持续稳定运行性好。(The invention discloses a forward osmosis-electric salt difference energy efficient continuous power generation device based on a porous medium, which comprises a fresh water source (1), an electric module (2), a forward osmosis module (5) and a salt water source (9), and is characterized in that: forward osmosis module (5) including forward osmosis unit (14), forward osmosis unit (14) include fresh water membrane channel (15) and salt water membrane channel (16) that the semi-permeable membrane made, crisscross range upon range of formation plane osmotic structure of fresh water membrane channel (15) and salt water membrane channel (16), fresh water import (151) of fresh water membrane channel (15) receive fresh water source (1) output, the fresh water behind two-dimensional micro-nano membrane channel (12) in electronic module (2), salt water import (161) of salt water membrane channel (16) receive the salt water of salt water source (9) output. The power generation device has the advantages of high system mass transfer efficiency, high system energy conversion efficiency and good continuous and stable system operation performance.)

1. The utility model provides a high-efficient continuous power generation facility of poor ability of forward osmosis-electronic salt based on porous medium, includes fresh water source (1), electronic module (2), forward osmosis module (5) and salt water source (9), its characterized in that: forward osmosis module (5) including forward osmosis unit (14), forward osmosis unit (14) include fresh water membrane channel (15) and salt water membrane channel (16) that the semi-permeable membrane made, crisscross range upon range of formation of fresh water membrane channel (15) and salt water membrane channel (16) possesses forward osmosis channel layer (17) of plane osmotic structure, fresh water import (151) of fresh water membrane channel (15) receive fresh water source (1) output, the fresh water behind two-dimensional micro-nano channel membrane (12) in electronic module (2), salt water import (161) of salt water membrane channel (16) receive the salt water of salt water source (9) output.

2. The porous media-based forward osmosis-electrokinetic salt-difference energy efficient continuous power generation device of claim 1, wherein: the fresh water membrane channels (15) and the salt water membrane channels (16) are distributed in a cross mode, and any adjacent fresh water membrane channel (15) and salt water membrane channel (16) share the same semi-permeable membrane.

3. The porous media-based forward osmosis-electrokinetic salt-difference energy efficient continuous power generation device of claim 2, wherein: the forward osmosis unit (14) further comprises an upper cover plate (141) and a lower cover plate (142) which are oppositely arranged up and down and can be combined into a closed cavity, a salt water inlet side shell (143) and a salt water outlet side shell (144) which are communicated with salt water, a fresh water inlet side shell (145) and a fresh water outlet side shell (146) which are communicated with fresh water, wherein a forward osmosis channel layer (17) is arranged in the closed cavity to form the forward osmosis unit (14), and four side edges formed by pairwise joints of the salt water inlet side shell (143), the salt water outlet side shell (144), the fresh water inlet side shell (145) and the fresh water outlet side shell (146) are respectively connected with four side edges of the forward osmosis channel layer (17) through sealing parts, so that a space formed by the salt water inlet side shell (143) and the forward osmosis channel layer (17) can be communicated with a space formed by the salt water outlet side shell (144) and the forward osmosis channel layer (17) through the salt water membrane channel (16), The space formed by the fresh water inlet side shell (145) and the forward osmosis channel layer (17) can only be communicated with the space formed by the fresh water outlet side shell (146) and the forward osmosis channel layer (17) through the fresh water membrane channel (15).

4. The porous media-based forward osmosis-electrokinetic salt-difference energy efficient continuous power generation device of claim 3, wherein: the salt water inlet side shell (143) is provided with a salt water inlet channel (1431), the salt water outlet side shell (144) is provided with a salt water outlet channel (1441), the fresh water inlet side shell (145) is provided with a fresh water inlet channel (1451), and the fresh water outlet side shell (146) is provided with a fresh water outlet channel (1461).

5. The porous media-based forward osmosis-electrokinetic salt-difference energy efficient continuous power generation device of claim 1, wherein: the fresh water membrane channel (15) and the salt water membrane channel (16) are internally provided with corresponding grid structures for supporting semipermeable membranes; and saline water membrane channels (16) are arranged above and below any fresh water membrane channel (15) in the forward osmosis channel layer (17).

6. The porous media-based forward osmosis-electrokinetic salt-difference energy efficient continuous power generation device of claim 1, wherein: the fresh water membrane channel (15) and the saline water membrane channel (16) are formed by connecting semi-permeable membrane glue.

7. The porous-media-based forward osmosis-electrokinetic salt difference energy efficient continuous power generation device according to any one of claims 1 to 6, wherein: the forward osmosis module (5) comprises a forward osmosis unit (14) or a plurality of forward osmosis units (14) connected in parallel, the salt water inlet side of the forward osmosis module (5) is communicated with a salt water source (9) through a salt water supply pipeline (10), and the salt water outlet side of the forward osmosis module (5) is communicated with a salt water recovery tank (8) through a salt water recovery pipeline (10) with a circulating water pump (7).

8. The porous media-based forward osmosis-electrokinetic salt-difference energy efficient continuous power generation device of claim 7, wherein: the salt water recycling pipeline (10) is provided with a flow stabilizer (6), and the flow stabilizer (6) is positioned on the salt water recycling pipeline (10) between the circulating water pump (7) and the forward osmosis module (5).

9. The porous-media-based forward osmosis-electrokinetic salt difference energy efficient continuous power generation device according to any one of claims 1 to 6, wherein: the electric module (2) comprises an electric energy conversion unit (13) or a plurality of electric energy conversion units (13) connected in series and/or in parallel, two-dimensional micro-nano channel membranes (12) are arranged in any electric energy conversion unit (13), and any two-dimensional micro-nano channel membrane (12) can be connected with the digital source meter/electric energy collection mechanism (3) through a lead (4).

10. The porous media-based forward osmosis-electrokinetic salt-difference energy efficient continuous power generation device of claim 9, wherein: the two-dimensional micro-nano channel film (12) is made of boron nitride, molybdenum disulfide, graphene and carbon nano tubes.

Technical Field

The invention relates to the technical field of salt difference energy power generation, in particular to a forward osmosis-electric salt difference energy efficient continuous power generation device based on a porous medium, which has high system mass transfer efficiency, high system energy conversion efficiency and good system continuous stable operation performance.

Background

With the increasing global environmental pollution and energy crisis, the development and utilization of clean and renewable energy sources and the reduction of carbon emission have become the development trend of the world society and have important strategic significance. The natural energy contained in the ocean and generated by the special environment of the ocean, namely ocean energy, which accounts for about 70 percent of the surface area of the earth, is a green renewable energy with huge potential, and the energy is hardly limited by climatic conditions and has the characteristics of being green, stable, abundant in reserves, continuously renewable and the like.

The salt tolerance energy is the second largest energy form among many ocean energies and mainly exists at the mouth of a river. The scientific meaning of the method is that the chemical potential difference energy between two liquids with different salt concentrations can be converted into electric energy by utilizing a certain energy conversion mode. Due to the wide ocean coverage of the earth, river entrances distributed on the coastline are more densely distributed around the world with a theoretical content of about 1650 TWh/a (trillion watt-hours/year). In addition, the salt difference can be effectively utilized in salt lakes with rich fresh water and underground mineral salt areas. The salt difference energy can be directly used for generating electricity to meet daily production and living requirements of people, and can also be used for compensating electricity consumption in certain main production processes in a compensatory electricity generation process, so that the overall production efficiency is improved. At present, although scholars at home and abroad have achieved certain research results in the aspects of exploration and research and development of the salt-difference energy power generation technology, large-scale production application cannot be achieved due to the high cost of the salt-difference energy power generation system and the relatively low overall power generation efficiency. However, since the salt difference energy has the advantages of cleanness, reproducibility, wide occupied area, flexible applicability and the like, the development and research of the salt difference energy technology can inevitably open up a new road for solving the problem of energy shortage, developing and utilizing renewable energy sources and guaranteeing the sustainable development of economy in the long term benefit. Therefore, exploring the high-performance salt difference energy conversion mechanism, constructing a corresponding macroscopic high-efficiency power generation prototype device, and providing a systematic scientific theory and experimental support for realizing stable and large-scale power generation by the salt difference energy become important research subjects of current researchers.

A Forward Osmosis (FO) based POWER generation device and METHOD (PCT/SG 2012/000187-A Power GENERATING DEVICE, AND A METHOD OF GENERATING POWER BY FORWARD OSMOSIS) discloses a salt capacity POWER generation technology, which comprises two mass transfer processes: the forward osmosis process and the pressure-driven electric energy conversion process correspond to core elements of a semipermeable membrane and porous glass for providing a micro-nano channel respectively. The forward osmosis process refers to a mass transfer process in which water molecules in a solution spontaneously diffuse from a low-concentration solution region to a high-concentration solution region through a semipermeable membrane without external pressure input. The pressure-driven Electric energy conversion process means that when the micro-nano channel is in contact with an aqueous solution, excess ions in an Electric Double Layer (EDL) on the surface of the channel move forward under the action of a pressure field to form an Electric current; meanwhile, the surplus ions are gathered at the downstream end of the channel under the action of electrostatic force, so that an electromotive potential is generated; the resulting electromotive current and electromotive potential can supply electrical energy to an external circuit through electrodes placed on both sides of the porous glass. When the FO-EK salt differential energy power generation system operates, the spontaneously generated fluid flow in the osmosis module drives the fluid in the system to flow through the electric module, thereby generating electric energy which can be collected and utilized.

Compared with the traditional mainstream salt energy production power generation technology (namely, Pressure Retarded osmotic Pressure (PRO) and Reverse Electrodialysis (RED)), the technology skillfully uses the Pressure-driven electric energy conversion device to replace a mechanical water turbine power generation device in the PRO power generation technology, and the Pressure generated inside the system is far less than the Pressure in the PRO power generation system, so that the strength requirement on the semi-permeable membrane is greatly reduced, the service life of the semi-permeable membrane can be obviously prolonged, and finally, the membrane cost and the system operation cost can be greatly reduced. Meanwhile, the power generation technology realizes the power generation process by means of a pressure-driven electric energy conversion mechanism by virtue of a porous medium containing micro-nano channels, and compared with an ion exchange membrane applied to the RED power generation technology, the porous medium can be made of a wide material source and is low in cost, so that the FO-EK salt difference energy power generation technology is more suitable for future large-scale batch production.

Although the FO-EK salt poor energy power generation technology has a plurality of advantages, the energy conversion efficiency is far away from the energy conversion efficiency standard required by industrialized production, and the analysis and summary mainly have the following three technical defects:

(1) the mass transfer efficiency of the system is low

The forward osmosis device is used for researching the power generation performance of the system, the used membrane material is a planar membrane material, and the used osmosis cavity is a large-scale square cavity. According to the experience related to the mature reverse osmosis, the structure has very small effective mass transfer membrane area, and the concentrated solution which plays a role in the forward osmosis process is mainly concentrated on a thin layer (with the thickness of about 10) on the surface of the semi-permeable membrane due to the large cavity volume²Mum or so) and therefore the concentrated solution in the cavity far from the semipermeable membrane cannot exert the advantage of high osmotic pressure in time, resulting in mass transfer efficiency far lower than that of the roll-type reverse osmosis membrane element popular in the market.

(2) The system has poor energy conversion efficiency

For the porous medium of the core element for electric energy conversion, the power generation technology selects porous glass and porous polymerBulk dielectric materials such as porous ceramics. From electrokinetic energy conversion studies, it is known that the amount of surface charge of a microchannel and the size of the microchannel play a crucial role in the energy conversion process. First, the surface charge amount of the dielectric material used in the power generation technology is relatively low compared to that of some new materials (such as a single layer of molybdenum disulfide, a single layer of graphene, and porous materials such as aluminum oxide). Secondly, the dielectric block material micro-channel used by the power generation technology has different aperture sizes, and can generate the nano-channel aperture (the order of magnitude is about 1nm-10 nm) with high efficient electric energy conversion efficiency²nm) are extremely small, mostly concentrated on the order of μm where the efficiency of electrokinetic energy conversion is low. Therefore, the lower electrical energy conversion efficiency results in a relatively lower overall system energy conversion efficiency for this inventive design.

(3) The system has poor continuous and stable running performance

According to the design of the forward osmosis device, the concentrated solution is injected into the concentrated solution cavity at one time, and the concentrated solution near the semipermeable membrane is continuously diluted along with the continuous forward osmosis process, so that an ECP (External Concentration Polarization) phenomenon is generated. A great deal of research shows that the concentration polarization phenomenon is one of the main inducers for reducing the permeation efficiency and the permeation flow of the forward osmosis semipermeable membrane. For the design of the invention, the concentrated solution is diluted by the permeated water molecules, so that the permeation rate is reduced continuously, which means that the power for triggering energy conversion is lower and lower until the power approaches zero. Therefore, the designed operation mode of the invention can not provide constant power for the electric energy conversion module, and finally, the continuous stable operation performance of the system is poor.

Disclosure of Invention

The invention aims to solve the problems in the prior art and provides a porous medium-based forward osmosis-electrokinetic salt difference energy efficient continuous power generation device which is high in system mass transfer efficiency, high in system energy conversion efficiency and good in continuous stable operation performance of a system.

The invention aims to solve the problems by the following technical scheme:

the utility model provides a high-efficient continuous power generation facility of poor ability of forward osmosis-electronic salt based on porous medium, includes fresh water source, electronic module, forward osmosis module and salt water source, its characterized in that: the forward osmosis module include the forward osmosis unit, the forward osmosis unit includes fresh water membrane passageway and salt water membrane passageway that the pellicle made, the crisscross range upon range of formation of fresh water membrane passageway and salt water membrane passageway possesses the forward osmosis channel layer of plane osmotic structure, fresh water that fresh water membrane passageway's fresh water import received fresh water source output, behind the micro-nano passageway membrane of two-dimentional in the electronic module, salt water that salt water membrane passageway's salt water import received salt water source output.

The fresh water membrane channels and the salt water membrane channels are distributed in a cross-shaped mode, and any adjacent fresh water membrane channels and any adjacent salt water membrane channels share the same semi-permeable membrane.

The forward osmosis unit also comprises an upper cover plate and a lower cover plate which are oppositely arranged up and down and can be combined into a closed cavity, a salt water inlet side shell and a salt water outlet side shell which are communicated with salt water, a fresh water inlet side shell and a fresh water outlet side shell which are communicated with fresh water, a forward osmosis channel layer is arranged in the closed cavity to form the forward osmosis unit, and four sides formed by the connection of the salt water inlet side shell, the salt water outlet side shell, the fresh water inlet side shell and the fresh water outlet side shell are respectively connected with four sides of the forward osmosis channel layer through sealing elements, the space formed by the salt water inlet side shell and the forward osmosis channel layer can be communicated with the space formed by the salt water outlet side shell and the forward osmosis channel layer only through the salt water membrane channel, and the space formed by the fresh water inlet side shell and the forward osmosis channel layer can be communicated with the space formed by the fresh water outlet side shell and the forward osmosis channel layer only through the fresh water membrane channel.

The salt water inlet side shell is provided with a salt water inlet channel, the salt water outlet side shell is provided with a salt water outlet channel, the fresh water inlet side shell is provided with a fresh water inlet channel, and the fresh water outlet side shell is provided with a fresh water outlet channel.

The fresh water membrane channel and the salt water membrane channel are internally provided with corresponding grid structures for supporting a semipermeable membrane; and saline water membrane channels are arranged above and below any one of the dilute water membrane channels in the forward osmosis channel layer.

The fresh water membrane channel and the saline water membrane channel are formed by connecting semi-permeable membrane glue.

The forward osmosis module comprises a forward osmosis unit or a plurality of forward osmosis units connected in parallel, the salt water inlet side of the forward osmosis module is communicated with a salt water source through a salt water supply pipeline, and the salt water outlet side of the forward osmosis module is communicated with a salt water recovery tank through a salt water recovery pipeline with a circulating water pump.

And the saline water recovery pipeline is provided with a flow stabilizer, and the flow stabilizer is positioned on the saline water recovery pipeline between the circulating water pump and the forward osmosis module.

The electric module comprises an electric energy conversion unit or a plurality of electric energy conversion units connected in series and/or in parallel, two-dimensional micro-nano channel membranes are arranged in any electric energy conversion unit, and any two-dimensional micro-nano channel membrane can be connected with a digital source meter/electric energy collection mechanism through a lead.

The two-dimensional micro-nano channel film is made of boron nitride, molybdenum disulfide, graphene and carbon nanotubes.

Compared with the prior art, the invention has the following advantages:

the power generation device of the invention uses the forward osmosis technology as a power source for generating power by the whole system, uses the pressure-driven electric energy conversion technology to convert the fluid kinetic energy into electric energy, uses the semi-permeable membrane gluing mode with ingenious conception to provide a cross flow mode for two fluids with different concentrations in the forward osmosis unit and uses the steady flow circulation system to provide the precondition of continuous and stable operation for the whole power generation system, so that the power generation device has high system mass transfer efficiency, high system energy conversion efficiency and good continuous and stable operation performance of the system.

Drawings

FIG. 1 is a schematic diagram of a forward osmosis-electrokinetic salt difference energy efficient continuous power generation device based on porous media;

FIG. 2 is an exploded perspective view of a forward osmosis unit of the present invention;

FIG. 3 is a bottom perspective view of the direction of flow of fluid into and out of the housing in the forward osmosis unit of the present invention;

FIG. 4 is an exploded perspective view of a forward osmosis channel layer of the present invention;

fig. 5 is a perspective view of an exploded configuration of the housing of the forward osmosis unit of the present invention.

Wherein: 1-a fresh water source; 2-an electric module; 3-digital source meter/electric energy collection mechanism; 4-a wire; 5-forward osmosis module; 6-current stabilizer; 7-circulating water pump; 8-a salt water recovery tank; 9-saline water source; 10-a salt water supply pipeline; 11-a salt water recovery pipeline; 12-a two-dimensional micro-nano channel membrane; 13-an electrokinetic energy conversion unit; 14-forward osmosis unit; 141-upper cover plate; 142-a lower cover plate; 143-saltwater inlet side housing; 1431-a salt water inlet channel; 144-salt water outlet side shell; 1441-passage for brine water; 145-fresh water inlet side shell; 1451, fresh water inlet channel; 146-fresh water outlet side shell; 1461-fresh water outlet channel; 15-fresh water membrane channel; 151-fresh water inlet; 152-fresh water outlet; 16-saline water membrane channel; 161-saline water inlet; 162-salt water outlet; 17-forward osmosis channel layer; 18-semi-permeable membrane glue joint.

Detailed Description

The invention is further described with reference to the following figures and examples.

As shown in fig. 1-5: the utility model provides a high-efficient continuous power generation facility of poor ability of forward osmosis-electronic salt based on porous medium, including fresh water source 1, electronic module 2, forward osmosis module 5 and salt water source 9, electronic module 2 includes an electronic energy conversion unit 13, or a plurality of electronic energy conversion units 13 of establishing ties and/or parallelly connected, all be equipped with two-dimensional micro-nano channel membrane 12 in arbitrary electronic energy conversion unit 13, arbitrary two-dimensional micro-nano channel membrane 12 all can be connected with digital source meter/electric energy collection mechanism 3 through wire 4. The forward osmosis module 5 comprises a forward osmosis unit 14, the forward osmosis unit 14 comprises a fresh water membrane channel 15 and a salt water membrane channel 16 which are made of semipermeable membranes, the fresh water membrane channel 15 and the salt water membrane channel 16 are alternately laminated to form a forward osmosis channel layer 17 with a planar osmosis structure, and the salt water membrane channel 16 is arranged above and below any fresh water membrane channel 15 in the forward osmosis channel layer 17; the fresh water inlet 151 of the fresh water membrane channel 15 receives fresh water output by the fresh water source 1 and passing through the two-dimensional micro-nano channel membrane 12 in the electric module 2, and the salt water inlet 161 of the salt water membrane channel 16 receives salt water output by the salt water source 9.

In the porous medium-based forward osmosis-electric salt difference energy efficient continuous power generation device provided by the invention, the forward osmosis module 5 comprises a forward osmosis unit 14 or a plurality of forward osmosis units 14 connected in parallel, the salt water inlet side of the forward osmosis module 5 is communicated with a salt water source 9 through a salt water supply pipeline 10, and the salt water outlet side of the forward osmosis module 5 is communicated with a salt water recovery tank 8 through a salt water recovery pipeline 10 with a circulating water pump 7; the saline water recovery pipeline 10 is provided with a flow stabilizer 6, and the flow stabilizer 6 is positioned on the saline water recovery pipeline 10 between the circulating water pump 7 and the forward osmosis module 5.

As shown in fig. 2 and 4, the fresh water membrane channel 15 and the salt water membrane channel 16 are formed by semi-permeable membrane bonding, any adjacent fresh water membrane channel 15 and salt water membrane channel 16 share the same semi-permeable membrane, and a semi-permeable membrane bonding part 18 is shown in fig. 4; corresponding grid structures for supporting the semipermeable membrane are arranged in the fresh water membrane channel 15 and the salt water membrane channel 16, and all structures (not limited to the grid structures) capable of being applied to the supporting membrane channel can be applied to the forward osmosis unit 14 provided by the invention; the fresh water membrane channels 15 and the salt water membrane channels 16 are oriented in a criss-cross manner, and all planar or roll-type membrane gluing methods that can produce channels with a certain angle in a staggered arrangement can be applied to the forward osmosis unit 14 provided by the invention.

As shown in fig. 2, 3 and 5, the forward osmosis unit 14 further comprises an upper cover plate 141 and a lower cover plate 142 which are oppositely arranged up and down and can be combined into a closed cavity, a salt water inlet side shell 143 and a salt water outlet side shell 144 which are communicated with salt water, a fresh water inlet side shell 145 and a fresh water outlet side shell 146 which are communicated with fresh water, wherein the forward osmosis channel layer 17 is arranged in the closed cavity to form the forward osmosis unit 14, and four side edges formed by two-by-two connection parts of the salt water inlet side shell 143, the salt water outlet side shell 144, the fresh water inlet side shell 145 and the fresh water outlet side shell 146 are respectively connected with four side edges of the forward osmosis channel layer 17 through sealing parts, so that a space formed by the salt water inlet side shell 143 and the forward osmosis channel layer 17 can only be communicated with a space formed by the salt water membrane channel 16, the salt water outlet side shell 144 and the forward osmosis channel layer 17, and a space formed by the fresh water inlet side shell 145 and the forward osmosis The outlet side casing 146 communicates with the space defined by the forward osmosis channel layer 17. A salt water inlet channel 1431 is arranged on the salt water inlet side shell 143, a salt water outlet channel 1441 is arranged on the salt water outlet side shell 144, a fresh water inlet channel 1451 is arranged on the fresh water inlet side shell 145, and a fresh water outlet channel 1461 is arranged on the fresh water outlet side shell 146.

The material of the two-dimensional micro-nano channel film 12 used by the electric energy conversion unit 13 is not limited to a single-layer or multi-layer two-dimensional nano-film material such as boron nitride, molybdenum disulfide, graphene, carbon nano-tube and the like, and all porous materials capable of providing micro-nano channels with surface charges can be applied to the electric energy conversion unit 13.

The fresh water used in the present invention may be river water, lake water, municipal tap water, or the like, and the salt water may be seawater, industrial wastewater, or the like. Because this patent uses the concentration difference to generate electricity, the fresh water side also can use the other water sources that concentration is less than the salt water side concentration.

As can be seen from fig. 1, consistent with the power generation mechanism of the prior art, when the forward osmosis-electrokinetic salt difference energy efficient continuous power generation device based on porous media provided by the present invention operates, the spontaneously generated fluid flow in the forward osmosis module 5 will drive the fluid in the device to flow through the electrokinetic module 2 to generate power, thereby generating electric energy which can be collected and utilized. The scale of each module can be used for carrying out series/parallel connection of a plurality of electric energy conversion units 13 or parallel connection of a plurality of forward osmosis units 14 according to the actual power generation requirement; such as: the single electric energy conversion unit 13 can be enlarged and reduced in a certain proportion as required to meet the requirement, and the single forward osmosis unit 14 can be increased or reduced in the number of osmosis layers or the osmosis area as required to meet the requirement. In addition, in order to ensure power for the integrated power generation device, the side other than the salt water side can be opened, and the semipermeable membrane connected with the salt water and the subsequent system of the semipermeable membrane must be sealed.

The most important innovation of the invention is to deeply improve the forward osmosis unit, thereby overcoming the defect of low mass transfer efficiency of the system in the prior art. The improved structural details are shown in fig. 2-5, fresh water and salt water respectively flow through the shell channels and the membrane channels, the forward osmosis process is carried out in fluid thin layers near the semipermeable membrane and the semipermeable membrane sandwiched by the fresh water and the salt water, and water molecules flow from the fresh water to the salt water side under the driving of osmotic pressure difference. The semi-permeable membrane is soft and cannot be shaped, so that a membrane channel formed by gluing the semi-permeable membrane needs a certain framework to support a channel structure of the membrane channel. The technology that is comparatively ripe in the infiltration research field at present stage is reverse osmosis, and the graticule mesh structure that the thickness is less than 1mm is applied to the formula of book reverse osmosis membrane element that generally uses in this technology provides the runner for dense, weak solution, and this graticule mesh structure not only can make solution evenly reach the pellicle surface, more can provide the disturbance of certain degree to improve infiltration mass transfer efficiency greatly. Therefore, the present invention will employ this grid structure within the membrane structure fluid channels to provide critical tangential flow spaces and tangential turbulence for the forward osmosis process.

Compared with the prior art, the invention has the following advantages: the system has high mass transfer efficiency, high energy conversion efficiency and good continuous and stable operation performance. The specific analysis is as follows:

firstly, an efficient two-dimensional micro-nano channel membrane 12 (for example, single-layer or multi-layer two-dimensional micro-nano channel membrane materials such as boron nitride, molybdenum disulfide, graphene, carbon nano tubes and the like) is used in the electric energy conversion unit 13 to replace a porous glass block-shaped porous medium used in the prior art, the material of the two-dimensional micro-nano channel membrane 12 has the advantages of high surface charge, short channel, high effective channel rate and the like, and for the pure electric energy conversion efficiency under a certain pressure, the energy conversion efficiency obtained by using the material of the two-dimensional micro-nano channel membrane 12 is one to two orders of magnitude higher than that obtained by using the porous glass material, so that the defect that the system energy conversion efficiency is poor in the prior art is overcome.

Secondly, a salt water circulating system is embedded in the forward osmosis module 5, and the circulating system can enable salt water in the forward osmosis module 5 to generate effective and stable tangential motion, so that the concentration polarization phenomenon in the forward osmosis process is greatly reduced, and the forward osmosis mass transfer efficiency is greatly enhanced; and because the salt water is continuously updated in the operation process, constant power can be provided for the energy conversion of the electric module 2, so that the system can continuously and stably operate. The defect of poor continuous and stable operation performance of the system in the prior art is overcome.

Finally, the forward osmosis unit 14 was designed with the following 4 major features: 1) the forward osmosis flow channel is supported by a grid structure, the thickness of the forward osmosis flow channel is controlled to be the thickness of an effective fluid osmosis thin layer, the grid structure can enable fresh water and salt water to uniformly reach the surface of the semipermeable membrane, and can provide a certain degree of tangential disturbance to reduce the concentration polarization phenomenon at two sides of the semipermeable membrane; 2) except that the saline water in the upper edge flow channel and the lower edge flow channel of the forward osmosis channel layer 17 is subjected to single-side osmosis, the saline water in other saline water flow channels is subjected to efficient double-side osmosis, and the arrangement can enable the effective osmotic pressure of the saline water to be efficiently utilized; 3) the staggered flow channel layout can also make the effective osmotic pressure of the salt water be efficiently utilized; 4) compared with a roll type reverse osmosis membrane structure, the forward osmosis flow channel is designed into a plane osmosis structure, so that the flow resistance can be efficiently reduced, and the energy loss of a system is reduced; the mass transfer efficiency of the osmotic mass transfer module is greatly improved by the four characteristics, and the defect of low mass transfer efficiency of the system in the prior art is greatly overcome.

The above embodiments are only for illustrating the technical idea of the present invention, and the protection scope of the present invention cannot be limited thereby, and any modification made on the basis of the technical scheme according to the technical idea proposed by the present invention falls within the protection scope of the present invention; the technology not related to the invention can be realized by the prior art.