A solar-powered, directional light-transmitting brine liquid film evaporator

Abstract

The present invention provides a solar energy focusing and directional light transmission brine liquid film evaporator, which can realize the efficient coupling of solar energy focusing and heat collection temperature and brine desalination temperature, and improve the thermal energy utilization efficiency. The brine liquid film evaporator comprises a truncated cone-shaped reflective cone, an evaporating cylinder and a condensing hood which are sequentially mounted from the inside to the outside; the inner wall surface of the evaporating cylinder is divided into an upper and lower part, the inner wall surface of the upper part is sprayed with reflective material, and the inner wall surface of the lower part is sprayed with light absorbing material; the water body filled between the reflective cone and the evaporating cylinder; a focusing and directional light transmission unit for focusing and transmitting solar rays to the lower part of the inner wall surface of the evaporating cylinder; the light-heat conversion is completed by the light absorbing material on the lower part of the inner wall surface of the evaporating cylinder; a water distribution unit for distributing the feed brine on the outer wall surface of the evaporating cylinder to form a liquid film; a fresh water collection tank for collecting fresh water condensed on the inner wall surface of the condensing hood and a concentrated brine tank for collecting unevaporated brine on the outer wall surface of the evaporating cylinder.

Description

Technical Field

[0001] The invention relates to an evaporator, in particular to a brine liquid film evaporator based on solar energy, belonging to the technical field of solar energy concentration and brine distillation. Background Art

[0002] As a technology to increase the source of water resources, desalination has solved the problem of freshwater resource crisis in many countries and regions. Traditional desalination technology consumes a lot of fossil energy, which increases energy consumption and pollutes the environment. In order to reduce the high energy consumption and carbon emissions in the desalination process, researchers have combined solar energy utilization technology with the desalination system.

[0003] As one of the effective ways to solve the shortage of freshwater resources, the traditional solar desalination technology has the disadvantages of low solar energy flow density, large heat capacity of the water to be evaporated, poor integration of solar radiation focusing, heat transfer and heating links, separation of solar thermal collection unit and desalination unit, uneven heating of evaporation surface and large heat dissipation loss of the device. In addition, in the prior art, since the solar thermal collection unit and the desalination unit operate independently, there is a structural mismatch problem that the efficiency of the solar thermal collection system is low during high temperature period (the heat dissipation loss of the solar thermal collection system is large when the temperature is high, resulting in low efficiency) while the efficiency of the desalination system is high during high temperature period. Summary of the invention

[0004] In view of this, the present invention provides a solar energy focusing and directional light transmission brine liquid film evaporator, which can realize the efficient coupling of solar energy focusing and heat collection temperature and brine desalination temperature, improve the thermal energy utilization efficiency, and integrate the solar energy collection unit and the brine desalination unit into one, thereby reducing the footprint of the device and improving the device integration.

[0005] The technical solution adopted by the present invention is: a solar energy concentrating directional light transmission brine liquid film evaporator, comprising:

[0006] A truncated cone-shaped reflective cone, an evaporating cylinder and a condensing cover are sequentially mounted from the inside to the outside; the inner wall surface of the evaporating cylinder is divided into an upper and lower part, the inner wall surface of the upper part is sprayed with a reflective material, and the inner wall surface of the lower part is sprayed with a light-absorbing material;

[0007] A body of water filled between the reflective cone and the evaporation cylinder;

[0008] A focusing and directional light transmission unit for directionally focusing the sunlight and transmitting it to the lower part of the inner wall surface of the evaporator tube; light-heat conversion is completed through the light-absorbing material at the lower part of the inner wall surface of the evaporator tube;

[0009] A water distribution unit for distributing the feed brine on the outer wall of the evaporation cylinder to form a liquid film;

[0010] A fresh water collection tank is used to collect fresh water condensed on the inner wall of the condensation hood, and a concentrated brine tank is used to collect unevaporated brine on the outer wall of the evaporation cylinder.

[0011] As a preferred embodiment of the present invention, the focusing and directional light transmission unit comprises: a Fresnel lens, a convex lens and a secondary reflector;

[0012] The convex lens is coaxially embedded in the upper end surface of the evaporating cylinder;

[0013] The Fresnel lens is coaxially placed above the evaporation tube and outside the convex lens, and the umbrella-shaped edge of the Fresnel lens coincides with the upper end surface of the evaporation tube;

[0014] The secondary reflector is coaxially mounted on the upper end surface of the reflective cone, and the secondary reflector is located below the convex lens; the sunlight is converged to the convex lens through the Fresnel lens, and the light after passing through the convex lens is converged at the focal spot position of the secondary reflector.

[0015] As a preferred embodiment of the present invention, the convex lens is a flexible lens;

[0016] The flexible lens has a gas interlayer. When not heated, the surface of the flexible lens is in a flat state. When the gas inside the gas interlayer is heated and expanded, a convex lens is formed.

[0017] As a preferred embodiment of the present invention, the secondary reflector is a concave parabola or two or more concave paraboloids connected in sequence as a rotation reference plane formed by rotating 360° circumferentially; the upper end of the secondary reflector is located on the axis of the reflective cone, and the lower end is located on the upper end surface of the reflective cone.

[0018] As a preferred embodiment of the present invention, a plurality of light-transmitting heat shielding rings are spaced apart along the height direction on the inner wall surface of the evaporator tube; one end of the heat shielding ring is fixedly connected to the inner wall surface of the evaporator tube, and a gap exists between the other end and the outer wall surface of the reflective cone.

[0019] As a preferred embodiment of the present invention, the angle between the generatrix of the reflective cone and its axis is greater than the angle between the generatrix of the evaporating tube and its axis, thereby forming an annular space that is wider at the top and narrower at the bottom between the reflective cone and the evaporating tube.

[0020] As a preferred embodiment of the present invention, the outer diameter of the lower end surface of the reflective cone is consistent with the inner diameter of the lower end surface of the evaporating tube.

[0021] As a preferred embodiment of the present invention, the inner circumference of the inner wall of the evaporating cylinder within two-thirds of the height from bottom to top is sprayed with light absorbing material, and the inner circumference of the remaining part above is sprayed with reflective material.

[0022] As a preferred embodiment of the present invention, the reflective cone is filled with heat storage material.

[0023] As a preferred embodiment of the present invention, the water distribution unit comprises: a salt water storage tank, a water inlet pipe and an annular water distributor;

[0024] The outer wall of the evaporating cylinder is provided with a water absorbing material;

[0025] A plurality of water inlet pipes connected to the brine storage tank are distributed circumferentially on the outer circumferential surface of the evaporating cylinder, and the water inlet pipes are connected to an annular water separator arranged at the upper end of the evaporating cylinder; the feed brine is distributed on the outer circumferential surface of the evaporating cylinder through the annular water separator, and is absorbed by the water-absorbing material on the outer circumferential surface of the evaporating cylinder to form a liquid film on the outer circumferential surface of the evaporating cylinder.

[0026] As a preferred embodiment of the present invention, the condensation hood comprises a frustum at the upper end and a cylindrical ring at the lower end;

[0027] The bottom surface of the cylindrical ring closes the annular opening between the lower end surface of the condensation hood and the lower end surface of the evaporation tube;

[0028] An annular water baffle is coaxially arranged inside the cylindrical ring at the lower end of the condensation hood, and the annular water baffle divides the annular space between the condensation hood and the evaporation cylinder inside the ring into two parts, wherein the part between the water baffle and the evaporation cylinder is the unevaporated salt water collection area, and the part between the water baffle and the condensation hood is the condensed fresh water collection area; the concentrated brine tank is connected to the unevaporated salt water collection area through a pipeline, and the fresh water collection tank is connected to the condensed fresh water collection area through a pipeline.

[0029] Beneficial effects:

[0030] (1) The present invention uses a focusing and directional light transmission unit to focus sunlight onto the light-absorbing material on the lower part of the inner wall of the evaporator tube, and completes light-to-heat conversion in the light-absorbing area on the inner wall of the evaporator tube, thereby realizing the unification of the evaporation surface, the heating surface and the heat-using surface; Specifically: In the present invention, the reflective cone and the evaporator tube both adopt a truncated cone structure, and the outer surface area of ​​the truncated cone evaporator tube is small at the top and large at the bottom, which means that the liquid film area is small at the top and large at the bottom, and the amount of brine to be evaporated is small at the top and large at the bottom, and the required heat energy is less at the top and more at the bottom; while the inner surface of the reflective cone reflects light on the top and absorbs light on the bottom, so the light-to-heat conversion is more at the bottom, and the heat supply is less at the top and more at the bottom; In the present invention, based on the principle of total reflection, the incident light is transmitted in a direction and absorbed by the light-absorbing material on the inner surface of the evaporation area with a large volume of brine liquid film and converted into heat energy, thereby realizing the coordinated matching of heat use and heat supply in the brine distillation process.

[0031] In addition, the present invention reduces the energy loss during the non-co-directional transmission of light through the forward focusing and directional transmission of sunlight.

[0032] (2) The focusing and directional light transmission unit of the present invention combines a Fresnel lens, a convex lens, and a secondary reflector to achieve the forward focusing, unidirectional transmission, and directional reception of solar radiation directly in the water body, thereby avoiding the loss of solar energy in the process of converting solar energy into photothermal energy.

[0033] (3) In the focusing and directional light transmission unit of the present invention, the convex lens is a flexible lens with a gas interlayer. When not in operation, the flexible convex lens returns to a flat surface state, and the gas interlayer of the lens plays a role in heat preservation, reducing heat loss.

[0034] (4) In the present invention, the angle between the generatrix of the reflective cone and its axis is greater than the angle between the generatrix of the evaporating tube and its axis, thereby forming an annular space that is wider at the top and narrower at the bottom between the reflective cone and the evaporating tube, so that the filled water body forms a tapered wedge-shaped water body, while avoiding the formation of an annular heat dissipation surface between the lower end of the reflective cone and the lower end surface of the evaporating tube, so that the heat of the liquid film to be evaporated can be increased.

[0035] (5) In the present invention, the evaporation surface (i.e., the outer surface of the evaporation tube) is opposite to the condensation surface (i.e., the inner surface of the condensation hood), and the heat shielding ring arranged on the inner wall of the truncated cone evaporation tube delays the upward buoyancy of hot water in the wedge-shaped water body along the wall surface, thereby solving the problem of long heat and mass transfer distance, large thermal resistance, and large amount of non-condensable gas caused by the buoyancy and condensation of water vapor on the evaporation surface. The heating surface of the device is entirely used as the evaporation surface, thereby improving the utilization efficiency of the device for thermal energy. The heat shielding ring is arranged to delay the transmission of heat to the upper part of the wedge-shaped water body, thereby increasing the heat exchange time with the brine liquid film, thereby solving the structural mismatch problem of low efficiency of the solar thermal collection system during high temperature periods and high efficiency of the brine desalination system during high temperature periods.

[0036] (6) Filling the reflective cone with heat storage material can reduce the heat loss of the wedge-shaped water body, extend the heating time of the device and increase the daily water production of the device.

[0037] (7) The use of multi-parabolic concentrators can achieve directional transmission and multi-focus convergence of light in the wedge-shaped water body when the light distribution is uneven and the flexible convex lens is not in operation, thereby improving the utilization rate of thermal energy.

[0038] (8) The solar energy concentration and heat collection temperature in the evaporator is efficiently coupled with the brine liquid film evaporation temperature, integrating the solar energy concentration, heat collection, heat transfer and heat utilization links in the water body, avoiding the complex heat transfer process and lengthy heat transfer pipelines. The device occupies a small area and is simple and easy to operate, making it suitable for fresh water preparation in remote arid areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 The overall structural principle diagram of the solar energy concentrating and directional light transmission brine liquid film evaporator of the present invention;

[0040] Figure 2is a structural diagram of an umbrella-shaped Fresnel lens in the present invention;

[0041] Figure 3 This is a light path diagram of sunlight incident on a water body after the gas in the flexible lens expands in the operating state of the present invention (a, b, and c are incident sunlight);

[0042] Figure 4 This is a state diagram of the flexible lens of the present invention in a non-operating state;

[0043] Figure 5 This is a schematic diagram of a reflective cone filled with heat storage material in Example 2 of the present invention;

[0044] Figure 6 A schematic diagram of the secondary reflector of the present invention being replaced by a multi-parabolic secondary reflector;

[0045] Among them: 1-Fresnel lens; 2-flexible lens; 3-secondary reflector; 4-reflective cone; 5-wedge-shaped water body; 6-water absorbing material; 7-transparent heat shielding ring; 8-light absorbing material; 9-water baffle; 10-drain pipe; 11-fresh water collection tank; 12-concentrated brine tank; 13-evaporation cylinder; 14-condensation hood; 15-annular water distributor; 16-water inlet pipe; 17-heat storage material; 18-multi-parabolic secondary reflector. DETAILED DESCRIPTION

[0046] The present invention is further described in detail below with reference to the accompanying drawings and examples.

[0047] Embodiment 1:

[0048] In order to reduce the energy loss of solar radiation during transmission and improve the problems of low light utilization, poor compatibility between the concentrated heat collection temperature and the liquid film evaporation temperature, low energy flow density of the device, and large heat loss of the water body. This embodiment provides a solar concentrated directional light transmission salt water liquid film evaporator, which realizes the consistency of the focusing and light transmission directions and the high-density light energy directly completes the photothermal conversion on the inner wall of the evaporation tube, highly integrates the solar concentration structure with the salt water distillation and desalination part, has a simple device structure, is easy to maintain, and is suitable for areas with scarce fresh water resources and rich solar energy resources.

[0049] like Figure 1 As shown, the solar concentrated directional light transmission brine liquid film evaporator includes: a concentrated directional light transmission unit, a reflective cone 4, a wedge-shaped water body 5, an evaporation cylinder 13, a condensation hood 14, a water distribution unit, a fresh water collection tank 11 and a concentrated brine tank 12.

[0050] The focusing and directional light transmission unit is used to focus and transmit the sunlight to the wedge-shaped water body 5 in the device to complete the light-to-heat conversion, and includes: a Fresnel lens 1, a flexible lens 2 and a secondary reflector 3.

[0051] The evaporation tube 13 is a truncated cone-shaped tube structure with two ends open, and the upper end opening is closed by a flexible lens 2; the flexible lens 2 has a gas interlayer. In the operating state, after the flexible lens 2 receives the light converged by the Fresnel lens 1, the internal gas expands due to heat to form a convex lens with a thick middle and a thin edge (such as Figure 1 When not in operation, the convex lens returns to a flat surface (as shown in Figure 4 As shown in FIG. 1 , the gas interlayer of the flexible lens 2 plays a role in heat preservation and reduces heat loss.

[0052] like Figure 2 As shown, the Fresnel lens 1 is an umbrella-shaped structure, which is placed above the evaporation tube 13 and outside the flexible lens 2, and the umbrella-shaped edge of the Fresnel lens 1 coincides with the upper end surface of the evaporation tube 13. The reflective cone 4 is a truncated cone-shaped cylindrical structure with two ends open, which is coaxially mounted inside the evaporation tube 13, and the lower end surface of the reflective cone 4 is flush with the lower end surface of the evaporation tube 13; preferably, the outer diameter of the lower end surface of the reflective cone 4 is consistent with the inner diameter of the lower end surface of the evaporation tube 13 (if the outer diameter of the lower end surface of the reflective cone 4 is smaller than the inner diameter of the lower end surface of the evaporation tube 13, an annular heat dissipation surface will be formed between the two, increasing heat loss), and the upper end surface of the reflective cone 4 is located inside the evaporation tube 13 (that is, the height of the upper end surface of the evaporation tube 13 is greater than the height of the upper end surface of the reflective cone 4); and the angle between the generatrix of the reflective cone 4 and its axis is greater than the angle between the generatrix of the evaporation tube 13 and its axis, thereby forming a wedge-shaped space with a larger upper part and a smaller lower part (that is, a wider upper part and a narrower lower part) between the reflective cone 4 and the evaporation tube 13. A secondary reflector 3 is installed on the upper end surface of the reflective cone 4. The secondary reflector 3 is a concave parabola formed by rotating 360° around the circumference with the concave parabola as a rotation reference surface. The upper end of the concave parabola is located on the axis of the reflective cone 4, and the lower end is located on the upper end surface of the reflective cone 4 (that is, the diameter of the lower end surface of the secondary reflector 3 is consistent with the diameter of the upper end surface of the reflective cone 4).

[0053] Thus, the inner wall of the evaporation tube 13, the outer wall of the reflective cone 4, the inner wall of the flexible lens 2 and the outer wall of the secondary reflector 3 surround a closed wedge-shaped annular space that is wide at the top and narrow at the bottom, and water is filled in the space to form a wedge-shaped water body 5.

[0054] The inner circumference of the evaporation tube 13 is divided into two parts, the upper part of the inner circumference is sprayed with reflective material, and the lower part of the inner circumference is sprayed with light-absorbing material 8; in this example, the inner circumference within two-thirds of the height from bottom to top is sprayed with light-absorbing material 8, and the inner circumference of the rest of the upper part is sprayed with reflective material.

[0055] The sequential combination of the Fresnel lens 1, the flexible lens 2, and the secondary reflector 3 allows the sunlight to be focused and transmitted to the device to complete the light-to-heat conversion. The Fresnel lens 1 is placed above the flexible lens 2, and the flexible lens 2 is concentrically nested on the upper end of the evaporation tube 13 to form an upper wall. The lower circumference of the secondary reflector 3 coincides with the circumference of the upper wall of the reflecting cone 4. The light is converged to the flexible lens 2 through the Fresnel lens 1, and the gas in the flexible lens 2 expands due to heat to form a convex lens. The light after passing through the convex lens is converged at the focal spot position of the secondary reflector 3, and under the reflection action of the secondary reflector 3, it is directionally transmitted to the light-absorbing material 8 on the inner circumference of the evaporation tube 13 to heat the brine liquid film.

[0056] Combination Figure 3 Specific description of the working principle of the focusing and directional light transmission unit:

[0057] Based on the edge ray tracing principle and the symmetrical structure of the device, three rays a, b and c representing the sun's rays are selected at normal incidence on the left side of the device. The rays a, b and c are incident on the Fresnel lens 1 and converge to the flexible lens 2. The gas in the flexible lens 2 expands into a flexible convex lens due to heat. The rays converge through the flexible convex lens to the focal spot position of the secondary reflector 3. The secondary reflector 3 reflects the rays a, b and c. The ray a diverges and directly hits the inner wall surface at the middle position of the evaporation tube 13 and is absorbed by the light-absorbing material 8 on the inner wall surface; the ray b diverges to the inner wall surface above the evaporation tube 13, and after being reflected by the reflective material on the inner wall surface above, it passes through the wedge-shaped water body 5 and is further reflected by the reflective cone 4 to the light-absorbing material 8 on the inner wall surface below the evaporation tube 13 and is absorbed; the ray c is diverged to the inner wall surface above the evaporation tube 13, and is reflected by the reflective material to the bottom of the reflective cone 4. The light reflected by the reflective cone 4 reaches the bottom of the device and is absorbed by the light-absorbing material 8.

[0058] A condensation hood 14 is coaxially mounted on the outside of the evaporation tube 13, and the condensation hood 14 includes a truncated cone at the upper end and a cylindrical ring at the lower end; the generatrix of the truncated cone portion of the condensation hood 14 is parallel to the generatrix of the evaporation tube 13; the upper end surface of the condensation hood 14 is flush with the upper end surface of the evaporation tube 13, and the annular opening between the upper end surface of the condensation hood 14 and the upper end surface of the evaporation tube 13 is closed by an annular plate; the lower end is closed by a cylindrical ring with a bottom surface, and a small annular closed space is formed between the condensation hood 14 and the evaporation tube 13.

[0059] The water distribution unit is used to distribute the feed brine on the outer wall of the evaporation tube to form a liquid film, and includes: a brine storage tank, a water inlet pipe and an annular water divider; the outer circumferential surface of the evaporation tube 13 is attached with a water absorbing material 6; in addition, the outer circumferential surface of the evaporation tube 13 is provided with a water inlet pipe 16 (which can be one or multiple distributed along the circumferential direction), and the top of the water inlet pipe 16 is connected to the annular water divider 15 arranged on the outer circumferential surface of the upper end of the evaporation tube 13; the feed brine in the brine storage tank (not shown in the figure) sequentially passes through the water inlet pipe 16 placed on the outer wall of the truncated cone evaporation tube 13 to reach the upper end annular water divider 15, and the annular water divider 15 is provided with water diversion holes evenly spaced along the circumferential direction. After passing through the annular water divider above the evaporation tube, the brine is distributed on the outer circumference of the evaporation tube 13, and is absorbed by the water-absorbing material 6 on the outer circumference of the evaporation tube 13 to form a uniformly distributed liquid film on the outer circumference of the evaporation tube 13. The water vapor generated by the liquid film evaporating under heat rises in the small annular closed space to the condensation surface with lower temperature (i.e., the inner circumference of the condensation hood 14) to condense into fresh water.

[0060] An annular water baffle plate 9 is coaxially arranged inside the cylindrical ring at the lower end of the condensation hood 14, and the annular water baffle plate 9 divides the annular space between the condensation hood 14 and the evaporation tube 13 inside the ring into two parts, wherein the part between the water baffle plate 9 and the evaporation tube 13 is the unevaporated salt water collection area, and the part between the water baffle plate 9 and the condensation hood 14 is the condensed fresh water collection area; the concentrated sea salt water tank 12 is connected to the unevaporated salt water collection area through a pipeline, and the fresh water collection tank 11 is connected to the condensed fresh water collection area through a pipeline.

[0061] The working principle of the brine liquid film evaporator is:

[0062] After being converged by the Fresnel lens 1, the sunlight reaches the flexible lens 2. The gas in the flexible lens 2 expands due to heat to form a convex lens with a bulge in the middle. After passing through the convex lens, the light is transmitted to the focal spot position of the secondary reflector 3 to achieve forward focusing. After being reflected by the secondary reflector 3, part of the light enters the wedge-shaped water body 5 after being reflected by the reflective material above the inner wall of the evaporation tube 13. Based on the principle of total reflection, the light reflected by the reflective cone 4 is transmitted downward and absorbed by the light-absorbing material 8 below the evaporation tube 13. The other part of the light is directly absorbed by the light-absorbing material 8 after being reflected to complete the photothermal conversion, that is, the photothermal conversion is completed on the inner wall of the evaporation tube 13, thereby completing the directional transmission and photothermal conversion of the light. At the same time, the heated wedge-shaped water body 5 also provides heat energy for the liquid film to be evaporated. The feed brine reaches the upper annular water divider 15 through the water inlet pipe 16 placed on the outer wall of the evaporation tube 13, and enters the water absorbing material to form a liquid film after being distributed through the annular water divider 15. In the process of flowing from top to bottom, it is heated and evaporated by the wedge-shaped water body and the light absorbing material on the inner wall of the evaporation tube. The generated water vapor condenses into fresh water on the inner wall of the condensation hood with a lower temperature. Finally, under the action of the water retaining plate 9, the unevaporated brine enters the concentrated sea brine tank 12, and the evaporated and condensed fresh water enters the fresh water collection tank 11.

[0063] In practical applications, multiple devices can be connected in series and parallel to achieve modular operation according to different fresh water production needs.

[0064] Embodiment 2:

[0065] On the basis of the above-mentioned embodiment 1, since the density of the water body decreases after being heated, it will flow upward, and the diameter of the evaporation tube 13 increases from top to bottom, that is, the heat exchange area at the lower end is larger; in order to reduce the heat loss of the water body upward and increase the heat exchange time with the brine liquid film, a transparent heat shielding ring 7 is provided on the inner wall of the evaporation tube 13; and multiple heat shielding rings 7 are distributed at intervals along the height direction; one end of the heat shielding ring 7 is fixed to the inner wall of the evaporation tube 13, and the other end has a gap with the outer wall of the reflective cone 4; light can pass through the transparent heat shielding ring 7 to reach the lower part of the inner wall of the evaporation tube 13 and be absorbed by the light absorbing material 8. Under the obstruction of the heat shielding ring 7, the heated water body confines the heat to the inner wall of the evaporation tube 13, thereby increasing the heat exchange time with the brine liquid film.

[0066] After the heat shielding ring 7 is provided, the water body near the inner wall of the evaporating tube 13 is blocked by the multi-layer transparent heat shielding ring 7 during the upward flow when heated, thereby extending the heat exchange time with the brine liquid film on the outer wall of the evaporating tube 13, reducing the heat loss upward, and making the heat exchange with the liquid film to be evaporated more complete.

[0067] Embodiment 3:

[0068] On the basis of the above-mentioned embodiment 1 or embodiment 2, Figure 5 As shown, further, a heat storage material 17 is filled in the reflective cone 4, thereby reducing the heat dissipation loss of the wedge-shaped water body 5, extending the heating time of the device and increasing the daily water production of the device.

[0069] Embodiment 4:

[0070] Based on the above-mentioned embodiment 1, embodiment 2 or embodiment 3, Figure 6 As shown, in this example, the secondary reflector 2 adopts a multi-paraboloid secondary reflector 18, and the rotation reference plane of the multi-paraboloid secondary reflector 18 is a plurality of concave paraboloids connected in sequence.

[0071] By using the multi-parabolic secondary reflector 18, when the light distribution is uneven and the flexible convex lens 2 is not in operation, the directional transmission and multi-focus convergence of light can still be achieved in the wedge-shaped water body 5, thereby improving the utilization rate of thermal energy.

[0072] The above contents are further detailed descriptions of the present invention in combination with specific implementation methods, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A solar concentrated directional light transmission brine liquid film evaporator, characterized by: include: A truncated cone-shaped reflective cone, an evaporating cylinder and a condensing cover are sequentially mounted from the inside to the outside; the inner wall surface of the evaporating cylinder is divided into an upper and lower part, the inner wall surface of the upper part is sprayed with a reflective material, and the inner wall surface of the lower part is sprayed with a light-absorbing material; A body of water filled between the reflective cone and the evaporation cylinder; A focusing and directional light transmission unit for directionally focusing the sunlight and transmitting it to the lower part of the inner wall surface of the evaporator tube; light-heat conversion is completed through the light-absorbing material at the lower part of the inner wall surface of the evaporator tube; A water distribution unit for distributing the feed brine on the outer wall of the evaporation cylinder to form a liquid film; A fresh water collection tank is used to collect fresh water condensed on the inner wall of the condensation hood, and a concentrated brine tank is used to collect unevaporated brine on the outer wall of the evaporation cylinder.

2. The solar concentrated directional light transmission brine liquid film evaporator according to claim 1, characterized in that: The focusing and directional light transmission unit comprises: a Fresnel lens, a convex lens and a secondary reflector; The convex lens is coaxially embedded in the upper end surface of the evaporating cylinder; The Fresnel lens is coaxially placed above the evaporation tube and outside the convex lens, and the umbrella-shaped edge of the Fresnel lens coincides with the upper end surface of the evaporation tube; The secondary reflector is coaxially mounted on the upper end surface of the reflective cone, and the secondary reflector is located below the convex lens; the sunlight is converged to the convex lens through the Fresnel lens, and the light after passing through the convex lens is converged at the focal spot position of the secondary reflector.

3. The solar concentrated directional light transmission brine liquid film evaporator according to claim 2, characterized in that: The convex lens is a flexible lens; The flexible lens has a gas interlayer. When not heated, the surface of the flexible lens is in a flat state. When the gas inside the gas interlayer is heated and expanded, a convex lens is formed.

4. The solar concentrated directional light transmission brine liquid film evaporator according to claim 2 or 3, characterized in that: The secondary reflector is formed by rotating 360° around a concave parabola or two or more concave paraboloids connected in sequence as a rotation reference plane; the upper end of the secondary reflector is located on the axis of the reflective cone, and the lower end is located on the upper end surface of the reflective cone.

5. The solar concentrated directional light transmission brine liquid film evaporator according to any one of claims 1 to 3, characterized in that: A plurality of light-transmitting heat shielding rings are spaced apart along the height direction on the inner wall surface of the evaporating tube; one end of the heat shielding ring is fixedly connected to the inner wall surface of the evaporating tube, and a gap is formed between the other end and the outer wall surface of the reflecting cone.

6. The solar concentrated directional light transmission brine liquid film evaporator according to any one of claims 1 to 3, characterized in that: The included angle between the generatrix of the reflecting cone and its axis is greater than the included angle between the generatrix of the evaporating tube and its axis, thereby forming an annular space that is wider at the top and narrower at the bottom between the reflecting cone and the evaporating tube.

7. The solar concentrated directional light transmission brine liquid film evaporator according to claim 6, characterized in that: The outer diameter of the lower end surface of the reflective cone is consistent with the inner diameter of the lower end surface of the evaporating tube.

8. The solar concentrated directional light transmission brine liquid film evaporator according to any one of claims 1 to 3, characterized in that: The inner circumference of the inner wall of the evaporating cylinder within two-thirds of the height from bottom to top is sprayed with light absorbing material, and the inner circumference of the remaining part above is sprayed with reflective material.

9. The solar concentrated directional light transmission brine liquid film evaporator according to any one of claims 1 to 3, characterized in that: The reflective cone is filled with heat storage material.

10. The solar concentrated directional light transmission brine liquid film evaporator according to any one of claims 1 to 3, characterized in that: The water distribution unit comprises: a salt water storage tank, a water inlet pipe and an annular water distributor; The outer wall of the evaporating cylinder is provided with a water absorbing material; A plurality of water inlet pipes connected to the brine storage tank are distributed circumferentially on the outer circumferential surface of the evaporating cylinder, and the water inlet pipes are connected to an annular water separator arranged at the upper end of the evaporating cylinder; the feed brine is distributed on the outer circumferential surface of the evaporating cylinder through the annular water separator, and is absorbed by the water-absorbing material on the outer circumferential surface of the evaporating cylinder to form a liquid film on the outer circumferential surface of the evaporating cylinder.

11. The solar concentrated directional light transmission brine liquid film evaporator according to any one of claims 1 to 3, characterized in that: The condensation hood comprises a frustum at the upper end and a cylindrical ring at the lower end; The bottom surface of the cylindrical ring closes the annular opening between the lower end surface of the condensation hood and the lower end surface of the evaporation tube; An annular water baffle is coaxially arranged inside the cylindrical ring at the lower end of the condensation hood, and the annular water baffle divides the annular space between the condensation hood and the evaporation cylinder inside the ring into two parts, wherein the part between the water baffle and the evaporation cylinder is the unevaporated salt water collection area, and the part between the water baffle and the condensation hood is the condensed fresh water collection area; the concentrated brine tank is connected to the unevaporated salt water collection area through a pipeline, and the fresh water collection tank is connected to the condensed fresh water collection area through a pipeline.

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