CH626159A5 - Device for converting concentrated solar energy into heat as well as the use of this device for distilling a liquid - Google Patents

Description

The present invention relates to a device according to the preamble of claim 1 and a use of this device according to the preamble of claim 12.

It is well known that surfaces exposed to the sun absorb solar energy at least to a certain extent and that the absorption of this radiation results in heating of the material forming the surface. It is also known that electricity can be obtained from photoelectric devices exposed to sun rays.

A conventional system for obtaining heat at lower temperatures up to about 80 ° C consists of dark colored plates that absorb the sun's radiation and means for dissipating the heat from the plates, such as. B. a fluid system in which a heat-transporting fluid medium is circulated with heat exchange with the plates. It is also known to improve the efficiency of these systems by arranging one or more glass plates above the other plates in order to achieve a greenhouse effect to reduce heat losses. Nevertheless, the efficiency of such plate systems is low, about 30 to 40%, and they require a large area, which in turn leads to large heat losses, and finally they require high capital investments. Fresnel lenses and liquid lenses are known for collecting solar energy in one focus. For example, see U.S. Patents 3,915,148, 3,125,091, 937,013.3,965,683, 3,901,036, 60,109.1 081098, Japanese Patent 28-2130 and Australian Patent 131,069.

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However, none of the known systems is able to convert and store solar energy with high efficiency. The prior art also does not show how temperatures of the order of a few 100 ° C. can be generated at the same time, while at the same time lower temperatures are available which can be used for heating apartments and water or for other purposes. Also, there is no system in the prior art which is capable of storing thermal energy obtained from solar energy during the periods of interrupted sunshine for any period of time.

With regard to the generation of electrical energy, it is known that the concentration of solar energy on a photo element increases the electrical output signal of the cell. However, there is the disadvantage that the temperature increase of the photocell resulting from the concentration again limits the output power of the photocell. Known photoelectric devices produce a maximum of one watt per cell from non-concentrated solar energy, and the number of such cells required to produce one kilowatt makes them uncompetitive for normal purposes.

With regard to distillation arrangements working with solar energy, arrangements known for the distillation of sea water have low efficiencies and the costs of heating the water are high, since the amount of heat required for the evaporation of the water is not recovered from condensation but is lost.

It is an object of the invention to provide a device for converting concentrated solar energy into heat, with which one or two heat carriers can be heated to two different temperatures for better heat utilization. The use of this device must also be specified, which allows a liquid containing water to be distilled with a high degree of efficiency.

The device according to the invention is characterized by the features stated in the characterizing part of patent claim 1.

The use according to the invention is characterized by the features stated in the characterizing part of patent claim 12.

Means can also be provided which track the seasonal and preferably also hourly (time of day) position of the sun. In this way, at least one fluid medium in the elongated collector can be effectively heated to high temperatures on the order of a few 100 ° C.

When a fluid medium is mentioned in the present description and the claims, it can basically mean both a liquid and a gas. The fact that predominantly liquids are present in the examples means no restriction.

These and other aspects of the present invention will become apparent from the following description of exemplary embodiments thereof in conjunction with the accompanying drawings.

The invention is explained in more detail below, for example with reference to the drawing, in which the same reference numbers refer to the same parts:

1 is a schematic perspective representation of a device with an elongated liquid lens and an elongated collector, the lens being movable about a transverse axis in order to track the time of day in the sun, and wherein the lens and the collector are interconnected and movable about a longitudinal axis, to track the seasonal position of the sun;

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Fig. 2 is a cross-sectional perspective view of a series of longitudinally side-by-side liquid lenses and their frame, the lens having an opening to connect its interior with other lenses, and the arrangement can be used, one to replace the individual lens shown by a plurality of lenses arranged one behind the other in the longitudinal direction;

3 is a perspective view of a lens assembly having two separate plates for enclosing a lens liquid and a frame for connecting the plates to a liquid-tight lens;

Fig. 4 is a cross section of the lens and frame of Fig. 3 taken along line 4-4;

Fig. 5 is a schematic perspective view of another device in which plates of four liquid lenses are arranged longitudinally and directed towards elongated collectors, the plates and collectors communicating with each other and being movable on a shaft so is rotated so that the seasonal position of the sun can be tracked, and the lenses can be rotated about a common transverse axis in order to be able to follow the time of day sun position, as described with reference to FIG. 1;

Fig. 6 is a schematic perspective view of another device with elongated planar Fresnel lenses with a linear focal point and collectors with liquid-carrying lines, the lenses and collectors being interconnected and movable in the manner described with reference to Fig. 1;

Fig. 7 is a cross section of part of another collector comprising three liquid-carrying lines, the inner one being enclosed by the middle one and the middle one being enclosed by the outer one;

Fig. 8 is a schematic perspective view of a composite water distiller comprising individual devices, two in the same plane and the third at an angle to the two so that the focal points of the lenses in one vessels containing distilling water are provided at different locations thereof;

Fig. 9 is a schematic perspective view of a portable water distiller which is easily assembled and disassembled and has Fresnel lenses;

Fig. 10 is a cross-section of a photoelectric cell disposed in the liquid-carrying conduit to generate electricity from solar energy, with the liquid circulating inside and / or outside the conduit to remove the heat;

Figure 11 is a schematic cross section of a lens assembly with a central liquid lens and adjacent Fresnel type lenses having a profile J5 which is at an angle such that the Fresnel lenses have the same focal point as the liquid lenses, with the focal point on an elongated collector is located, which is in connection with the lenses, the lenses and the collector are movable for tracking after the sun;

Fig. 12 is a schematic perspective view of a device for substantially continuous distillation of water, in which the lens arrangement comprises Fresnel lenses and liquid lenses and has a plurality of focal points which are arranged at different depths in the water to be distilled, the Fresnel lens and the collector for Following the seasonal position of the sun are movable. Furthermore, a lens set for

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Preheating the incoming water to be distilled provided;

Fig. 13 is a schematic perspective view of another water distillation apparatus in which the lens assembly comprises two liquid lenses and multiple conduits to enable substantially continuous operation;

Fig. 14 is a schematic perspective view with two lenses through which the sun rays pass in succession to shorten the focal length of the lens system and which serve to produce a sharper focal point on a collector, the top of the collector being exposed to the heat generated by the infrared rays is and wherein the lenses and the collector are movable for tracking the position of the sun;

15 is a schematic cross section through a lens arrangement with a central lens and adjacent Fresnel lenses, which have a relief which has such an angular position that the adjacent Fresnel lenses have the same focal point as the central lens, the lenses being arranged such that the focal point of the lens arrangement is located in or on a collector which has two adjacent lines which enclose one another so that the solar energy can be absorbed for different times of the year without tracking means for the position of the sun;

Fig. 16 is an enlarged schematic cross section of one of the Fresnel lenses of Fig. 15;

Fig. 17 is a schematic perspective view with a set of Fresnel lenses arranged in the east-west direction, of which the lenses at east and west ends are angled with respect to the inner lens, with a given lens primarily solar energy aimed at or at the collector at a certain time of day; and

Fig. 18 is a perspective view of a composite lens arrangement in which the lenses are arranged and provided at such an angle as shown in Figs. 15 and 17 so that solar energy is in or on the collector both during the different seasons as well as different times of day.

1 shows a solar energy collecting device which comprises a collecting lens filled with a light-refractive liquid and a collector for the solar energy containing a liquid. The device 20 has an elongated liquid collecting lens 22 and a collector 24 in the form of elongated lines containing liquid. The elongated liquid lens 22 comprises the plates 26, 28 which let the solar energy through, which preferably consists of separate plates 26, 28 which are arranged in a frame 30 and which are spaced apart from one another in order to receive the liquid 31 which transmits the sun energy. In the embodiment shown in FIG. 1, the upper lens plate 26 is convex and the lower lens plate 28 is planar. The respective sides 32, 34 of the lens plates 26, 28 and the ends of the lens plates (not shown in Fig. 1) are sealed in a manner to be described to create a liquid tightness. Alternatively, means not shown in FIG. 1 for adding and removing or circulating the liquid 31 and air can be provided in the sides and / or ends of the lens plates. The lenses can also be arranged side by side in the longitudinal direction and transversely (radially), which will be described later. In the embodiment shown in FIG. 1, the collector 24 comprises an outer elongated line 36 which encloses an inner elongated line 38, both of which are tubular. The line 36 is arranged in an insulating container 40 and is surrounded by insulating material, with the exception of an opening 44 5 which extends in the longitudinal direction above the line 36. The opening 44 is closed by the heat-insulating plate 46 which transmits solar energy. The plate 46 is suitably made of glass or plastic, and the insulating material 42 is, for example, a foam, such as polyethylene foam. A sealing material such as silicone, for example, is provided between the plate 46 and the container 40 in order to seal the container in a liquid-tight manner. The collector 24 is below the lens 22 and the theoretical focal line 48 is located on or along the collector. The axis of the lens (and the device 15 is oriented in the east-west direction.

The frame 30 and the lens 22 are pivotally supported in the frame 50, which is pivotable about the transverse axis 52 on the pin 53 in pivot bearings, not shown. On the opposite sides 20 of the frame 30, near the adjacent sides 32, 34 of the lens, cables 55 (only one of which is shown) are attached at their opposite ends and wound around rollers or pulleys 58 so that the cables are in a common direction can move towards a drive 25 arrangement, not shown. Movement of the cables 55 in the direction of the arrows pivots the lens 22 about the axis 52 and moves the plate 26 to the west.

Movement of cables (not shown) attached to the other end of the frame 30 pivots the lens 22 30 about the axis 52 and moves the plate 26 to the east. In this way, the lens 22 can be rotated in the east-west direction in order to be able to follow the hourly sun movement. In addition, the lens 22 and the collector 24 can be rotated in the north-south direction about the longitudinal axis 60 in order to be able to follow the seasonal movement of the sun. The frame 50, in which the lens 22 is mounted, is pivotally mounted near the ends of the lens in the support frame 62 by means of pins 64 (only one of which is shown) in swivel bearings (not shown). The collector 24 is connected to the frame 50 via struts 66. The frame 5 and the collector 24 can therefore be pivoted as a unit about the axis 6, so that the relative orientation between the collector and the lens remain unchanged. Cables 68 (only one of which is shown) are attached to one side of the collector 45 in order to be able to pivot the lens and the collector in the north direction. Cables 7 (only one of which is shown) are attached to the other side of the collector in order to be able to pivot the lens and the collector to the south into a position which is shown in broken lines. The cables 68 and 70 are also wrapped around pulleys 58 so that the cables can run in a common direction to a drive, not shown. The lens and collector are pivotable over 55 a total angle of approximately 47 degrees during the year in a north-south direction. The drive can comprise, for example, electric motors that are driven and controlled by sensors such as photo transistors or by electrical time switches. In addition to the 60 means illustrated in FIG. 1 and described above, automatic, semi-automatic or manually operated means for tracking after the sun position may be present. A drive uses an electric motor, the shaft of which is extended by a small angle, 65 when direct or focused sunlight hits a photocell or thermocouple. Hydraulic drives can also be used to move the lenses and collectors. Other drives use a timer switch

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direction or a device with a weight and a pulley. The movement of the sun affects the output signal of the photocell to control the motor, or the motor is actuated by a timer to rotate the shaft in small angular increments, or it rotates the device with weight and pulley directly. As mentioned, complete drives for moving the lenses and for detecting the position of the sun are known and are not shown. Parts of the drives for tracking the device according to the position of the sun are, however, included in the drawings. While the daily or hourly tracking to improve the collection of solar energy is preferably present, "nasty tracking is not absolutely necessary since the collector and the lens are already oriented essentially in the east-15 direction anyway. By combining the movements of the lens and the collector, the focal point of the lens is always held on the collector, regardless of the season. The tracking arrangement described above considerably improves the collection of solar energy 2 ', since the device is always oriented in directions which point directly into the sun, both seasonally and preferably also during the day.

As already mentioned, the collector is arranged in the theoretical focal point 48 of the lens 22 and, in the 25 embodiment of FIG. 1, the lines 36 and 38 let the solar energy through, the theoretical focal point 48 being located within the inner line 38. Lines 36 and 38 contain heat-transporting liquids 54 and 56. Since the concentration of solar energy in the line in which the theoretical focal point is located is greatest, i. H. in the liquid 56 within the line 38, the liquid 56 can be heated to a relatively high temperature. For this reason, such a liquid is chosen that has a high boiling point of, for example, 35 150 to 350 ° C. Liquids, glycerols, mineral oils or paraffin oils can be considered as such liquids, for example and without limitation. Accordingly, during the sunshine periods, the liquid 56 is heated to a temperature above 100 ° C., for example 200 ° C., the precisely reached temperature being influenced by many factors such as the flow rates of the liquids 54, 56, the diameter of the lines 36, 38, the sun intensity and -Position, insulation, heat transfer coefficients u. The like. Liquid 54 has a boiling point less than 4S the boiling point of liquid 56, preferably at least 50 ° C lower than the boiling point of liquid 56, and preferably in the temperature range of -60 ° C to about 100 ° C. As such liquid For example, water is suitable. Preferably, liquid 54 also has a low latent evaporation well of, for example, about 20 cal / g to about 370 cal / g. As such liquids, for example and without limitation, refrigerants, solvents, hydrocarbons, alcohol and the like. Like. come into consideration. S5

In operation, the solar energy in liquid 56 (when the lubricating oil has been selected) is concentrated in line 38 and raises the temperature of the oil to approximately 200 ° C. Since the focal point of the lens 22 is theoretically line-shaped, the liquid 56 is continuously heated 60 as it runs along the focal line. Liquid 54 (when the water was selected) surrounds the oil and line 38 and is primarily heated by line through the oil. Both liquids (oil and water) are circulated at predetermined flow rates to achieve the desired temperatures and can be used for various applications of heat. For example, the water can reach 70 to 80 ° C

or more heated and used for space heating and hot water preparation. The water can also be heated to lower temperatures and used for example in swimming pools. The oil having the higher temperature can be used in applications which require a higher temperature, also in the industrial sector, or can only be used to heat the water. As the temperature of the liquid 56 increases as it passes the focal line of the lens, liquids of many different temperatures can be obtained by attaching ports for the inlet and / or outlet of liquid at different locations along the focal line. Liquid 54 may also be heated and the steam or superheated steam used to generate mechanical power in expansion assemblies such as motors and turbines, which in turn provide electrical energy. A closed system (not shown) is preferably used by returning the condensed liquid to the collector 24. In such applications, the liquid 54 can consist of refrigerants, solvents, hydrocarbons, alcohol.

As already mentioned, a serious disadvantage of solar energy systems in general and of the known devices in particular is the difficulty of storing energy during periods without or without sun, for example during the night or during periods of cloudy weather. For such periods, heat is stored in the liquid 56, which is heated to a temperature which is at least 50 ° C. higher than the temperature of the liquid 54 during normal operation of the system. Therefore, even if the liquid 56 is not or only to a lesser extent heated by solar energy, it stores heat and continues to supply heat to the liquid 54 because of a temperature difference between the liquids. The circulation of the liquid 56 is preferably set during these periods. The liquid 56 transfers heat to the liquid 54 until the temperature difference between the two liquids has become relatively small. The length of time that the liquid 56 transfers and / or stores heat depends on the initial temperature of the liquid 56, the temperature difference between the liquids, the physical properties (specific heat, boiling point, latent heat, etc.) of the liquids and the use of the liquid 54 from.

The liquid 31 in the lens 22 can be connected to one of the lines in the collector 24 in order to extract heat from the lens liquid and thereby keep it at a suitable temperature, while at the same time the solar energy absorbed by the lens liquid, for example for the preheating of FIG the lines 36 and / or 38 circulating liquids can be used.

1, the collector 24 comprises tubular lines 36, 38. However, the lines do not need to have a circular cross section and in other cases other configurations such as rectangular cross sections are preferable. A rectangular configuration may be desirable if there are deviations in the theoretical focal line. A rectangular shape allows focal line 48 to move while being held in line 36. The focal line 48 may be located on the surface of the conduit 36, and in such a case the surface of the conduit 30 need not transmit solar energy and is preferably colored dark.

The devices shown in the remaining figures and described below are oriented in the longitudinal direction east-west and facing the sun. Furthermore are

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the elongated lenses or lens systems and the elongated collectors and their lines are arranged substantially along parallel longitudinal axes. Furthermore, the concentrators and collectors are preferably movable, and means are preferably provided to move them and to follow the seasonal and preferably the hourly position of the sun. However, movement of the lenses can be omitted if the focal length of the lenses is short, so that the shift in the focal line from season to season remains small and remains within the circumference of the inner line 38 of the collector. Hand-operated, automatic or semi-automatic drives for achieving the follow-up movement of the systems and / or lenses on a seasonal or hourly basis are known. While only a single lens is shown in FIG. 1, many lenses can be provided in the longitudinal and transverse directions.

Lines 36 and 38 in Fig. 1 may both have impervious heat conductive surfaces, and the lower portions of the surface of line 36 and / or line 38 are preferably either darkened by black paint 20, or are the line or lines in the bottom half of their surfaces with black metallic foils so that the solar energy is not let through and the heat absorption from the solar energy is promoted. 25th

In addition, plate 46 provides a greenhouse effect in the collectors. The container 40 is preferably made of an insulating material to prevent heat loss. Reducing heat loss is particularly important during periods of missing or reduced sunshine. However, as will be described more fully, the plate 46 can be eliminated if it is not desired to retain heat at the focal line of the lens, for example if photo elements are located there. The theoretical focal line of the lenses 35 is preferably located in the inner liquid in order to avoid further heat losses due to the fact that the outer liquid acts as an insulator. 1 are preferably made of colorless and transparent glass or plastic, while the tubes, which do not have to transmit solar energy, are preferably made of metal and preferably steel, copper or aluminum and all preferably on their lower surface parts are made dark.

The area of the collector surfaces can be much smaller than the area of the concentrators and can be in the range of only 1 to 10% of a conventional collector in the form of a flat plate, whereby the heat losses are reduced accordingly. In addition, since less material is used for such collectors, its costs are reduced.

The collector systems can also have a different number of lines than two and other than circular cylindrical cross sections. The lens configurations and the lenses and lens systems can also be different from those shown in FIG. 1.

The lens in Fig. 1 is held by suitable frames and support members. For example, the lens 80 in FIG. 2 is held in a frame 88. As shown there, a plurality of lenses are arranged one behind the other in the longitudinal direction at their ends. They are held by longitudinal struts 92 and transverse struts 94. The lenses can be glued in the frame, for example. The theoretical focal line 96 of the lenses is located on and along the collector 98. Openings 100 are provided in order to admit or discharge liquid 31 and / or air. The openings 100 can be connected by pipes in order to circulate the liquid

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accomplish. The openings can also be made at other locations. As already mentioned, the plates forming the lenses can be extruded in one piece or produced as a blow molding or comprise separate plates which are welded together, for example. 3 and 4, the upper curved plate 26 and the lower flat plate 28 are separate parts and held together in a liquid-tight manner by the frame 104. The frame 104 comprises two grooves 106, 108 running in the longitudinal direction. The upper groove 106 is curved and dimensioned to receive the upper curved plate 26, while the lower groove is straight and is dimensioned such that it can receive the flat plate 28. The edges of the respective separate plates are inserted into the respective grooves with sealing material 110. The ends of the plates are joined together in a similar manner. Material 110 may include a gasket or similar flexible molding and / or deformable material such as silicone to form fluid tight connections. In this way, the lenses in which two independent plates are put together or the lenses are extruded or blown are relatively easy to manufacture and relatively inexpensive. The required radius of curvature of the curved convex plate and the focal distance from the lens to the collector depend on the width of the plates, the maximum distance between the plates and the refractive index of the liquid between the plates. Liquids with a higher refractive index shorten the required radius and the focal distance.

Depending on the lens liquid used and the distance between the lens plates, part of the infrared rays striking the lens in the range of approximately 0.7 to 4 microns will not pass through the lens. Rather, some of the infrared rays will be absorbed directly by the liquid and heat it up. Another part of the infrared rays is absorbed by the lens plates, which are heated up and in turn partially heat the liquid. Part of the solar energy is reflected by each plate, again a part of the reflected solar energy is reflected to the inside of this plate into the inside of the lens and again partly absorbed by the lens liquid. Only a little of the visible rays in the wavelength range from about 0.25 to about 0.7 microns is absorbed in a transparent and colorless lens liquid and the transparent and colorless lens plates. For some applications, it is desirable to minimize the absorption of infrared rays, for example when it comes to generating as much heat as possible at the focal point of the lens. In other applications, it may be desirable to heat the lens liquid and / or to develop as little heat as possible in the focal point of the lens while at the same time allowing as much of the light rays as possible to pass through, for example when photo elements are placed in the focal point of the lens. In the previous case, the distance between the lens plates is made as small as possible, for example about 2.5 cm at the point of the maximum distance between the lens plates. The lens liquid is selected so that it absorbs only a minimal portion of the infrared radiation at ambient temperature and preferably has a refractive index of at least 1.35. Liquids such as hydrocarbons, mineral oils, solvents, solutions such as salt water etc. are transparent, colorless and absorb far less infrared radiation than water. Preferably, non-corrosive liquids with a suitable boiling temperature are selected on glass and plastic. Some liquids with a ho

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hen refractive index and low absorption of infrared rays such as trichlorethylene and toluene have a corrosive effect on plastics such as acrylic resin. When using such corrosive liquids, the lens plates exposed to the liquid are covered by foils made of Teflon or 5 coatings of epoxy resin such as LuciteRD, which are not corroded by the lens liquid. In the latter case, the distance between the lens plates is made as large as possible, for example about 10 cm at the point of the greatest distance between the lens plates, and the liquid is selected so that it absorbs a maximum amount of infrared at ambient temperature while still being transparent and is colorless.

The degree of infrared absorption also depends on the material used for the lenses. For example, a water-light glass with approximately 1.5% absorption or a plastic with a similarly low absorption can be used for low absorption if a lens liquid such as e.g. B. an aqueous salt solution is present. However, if a high level of infrared absorption is desired, for example in electricity generation applications where solar energy is focused on photo elements, glass or plastic lenses with lens fluids having an infrared absorption of, for example, 20% can be used. In the latter case, water is preferably used when infrared radiation is to be absorbed. In certain areas, an anti-freeze is added to the water to prevent freezing. When water is used in the collector, an anti-freeze is also added to the collector water. With water as the lens liquid and the greater distance (for example approximately 10 cm) between the lens plates, there is an increased infrared absorption by the lens liquid and a corresponding increase in the heating thereof. The heat in the lens liquid 35 can be recovered in heat exchangers and used to heat and / or preheat the collector liquid in the manner already described. The heat can also be used to heat water in the home or for other purposes, to heat buildings or to generate electricity by overheating low-boiling liquids, the steam of which is then expanded in expansion devices such as turbines or motors. Since the lens liquid transmits most of the light rays, the generation of electricity by the photocells is hardly reduced, while the lens liquid heats up and heat is used in the manner mentioned for heating purposes and / or for the production of further electricity. In this way, the invention offers a very economical combination of equivalent heat and electricity generation.

5, the device 70 consists of sheets 71 of liquid lenses 22. Each sheet comprises 4 liquid lenses 22, which are adjacent to one another in the longitudinal and transverse directions. The panels are rotatably supported to follow the sun seasonally and hourly. The frame 50 is supported on shafts 64 which are rotatably connected to the frames 62 at opposite ends thereof, for example via bearings. One end of the shaft 64 is with a drive, not shown, such as. B. connected to an electric motor. The lenses 22 and the frame 50 60 can be rotated about the longitudinal axis 60 by rotating the shaft 64 for seasonal tracking of the sun. The frame 30 is pivotally mounted on the frame 50 by means of pins 52 and can be moved with the lenses 22 via a common transverse axis 53 for following the sun position in the manner described in connection with FIG. 1.

A planar refractive element 126 is shown in FIG. 9

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provided, which comprises a rigid frame which surrounds a plate made of plastic or glass, in which concentric small spaced rings or microprisms are formed by pressing or molding, the division of which is, for example, three to four microprisms / mm. The planar refractive element 126 behaves like a planar Fresnel lens. Solar energy impinging on the refractive element 126 is concentrated by the microprisms in a theoretical focal point. The light-refracting element 126 can be arranged next to one another in the longitudinal and / or transverse direction. The system can be arranged such that the focal points of the lenses 126 are located in or on the surface of lines 36 and 38, the series of discrete focal points over a length of length resulting in a focal line composed of discrete focal points, as shown in FIG. 9 is shown in a liquid to be distilled.

The device 130 of FIG. 6 uses elongated light-refracting elements 132 which have longitudinally extending microprisms 134 which act like longitudinal Fresnel lenses. The lenses 132 and the collectors 124 are arranged such that the focal line of a row of lenses is located on the respective collector, as was described in connection with FIG. 5. The lenses and collectors are interconnected and, like the systems of FIGS. 1 and 5, movable.

FIG. 7 shows an arrangement with three lines, in which the inner line 139 is surrounded by a middle line 141. The provision of three lines allows the use of three different liquids and allows the use of the liquid at different temperatures for many different applications and finally allows a greater displacement of the focal line. The outer line 36 may be transparent and the fluid medium in the outer line may be a gas, the outer line and the gas creating a greenhouse effect over the inner lines 141, 139.

As already described, the present invention can be used in many energy applications and can also be used advantageously for the distillation or other treatment of water by evaporation and condensation. In a typical case, the water is seawater or brackish water and needs to be desalinated, or it is water or a liquid containing minerals or other substances, or it is industrial waste water or contaminated water that is to be cleaned and distilled. The refractive concentrators and collectors are arranged in distillation systems, the heat of condensation preferably being recovered and heat in the condensed water and in the drained brine also being recovered in the manner to be described.

The device 160 shown in FIG. 8 comprises several groups, each of which comprises a three-lens arrangement 164. Each lens system 164 is disposed above a longitudinal central channel 166 and parallel elongated side channels 168 such that the central portion of the lens system is located above the central channel and the outer longitudinal edges of the other two lenses are above the side channels. Each lens is inclined and the bottom plates 28 of the lenses are flat. The water 170 to be distilled is poured into the central channel up to a certain height. The longitudinal focal lines F of the lenses are arranged within the channel 166, preferably at different locations and at different heights, the different heights corresponding to the different water depths in the channel 166. In Fig. 8 the line liquid 31 is preferred

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wise salt water. The solution of the salt dissolved in deux water (NACI) absorbs less infrared rays than water alone. Thus, if it is desired to reduce the absorption of infrared rays in the lens liquid, a salt / water solution is preferably used as the lens liquid. If seawater is to be desalinated, sea water is preferably used as the lens liquid and is preferably also preheated in the container containing the water to be distilled. Valves are provided in the pipes to regulate the draining of water and the circulation of liquids. In operation, the water 170 is heated and evaporated by the solar energy concentrated in the focal lines F. The vapor strikes the lower plates 28, is condensed thereon, and flows therethrough to be drained from the edges thereof into the side channels 168. The interiors of the liquid lenses communicate with the interior of channels 166 through conduits 177 (only a set of which is shown) and also with each other. A heat exchanger 179 can be provided within the channel 166, in particular in order to transfer heat from the condensed water in the channel 168 to the water in the channel 166. The water in the liquid lenses is circulated through the lenses and channels. In this way, the heat released by the condensation of the vapor is transferred to the water in the lenses via the plates 28, and the heat absorbed by the water in the lenses from the condensing vapor is returned to the system in the channels. In this way, the water to be distilled can be heated or preheated. The lenses 22 are arranged such that the focal lines F remain within the channels 166 regardless of the seasonal and daytime position of the sun, the focal lines moving along the paths indicated in the channel 166 by the dash-dotted lines. The focal lines are therefore not shifted outside of the channels 166, and it is therefore not necessary to provide means for moving the lenses and for tracking the position of the sun. The heat in the distilled water can also be used to preheat or heat the water to be distilled. The distilled water can only be a few degrees below the steam temperature. The recovered heat can also be used for other purposes and the lens liquid and / or the condensate can be passed through heat exchangers to remove the heat therein. This is important because the latent heat of about 45 cal / g required to evaporate the water 170 is released in addition to the sensible heat by the condensation of the steam and is essentially recovered from the condensate and by the circulating water in the lenses on which the Steam condenses, is fed back into the system. The latent warmth and the detectable warmth are considerable and would otherwise be lost. This leads to a significantly higher efficiency of the system compared to sun distillation apparatuses, in which channels filled with the water to be treated are only covered with glass or plastic plates or foils that absorb the sun. Circulating the water in the lenses also cools the lower lens plates 28 and promotes condensation thereon. Lines 175 and 176 are provided to fill and empty the respective channels. The water 170 can be maintained between predetermined levels by a float system which includes a float 178 and relay 180, 182. Movement of the float actuates the respective relays and starts or stops a pump or an engine valve (not shown). A similar arrangement can also be found in the side channels

168 can be used. A gravity drainage arrangement can also be used to keep the level of distilled water in the side channels between predetermined levels. The S respective channels are connected to each other in order to create essentially the same level levels in the respective channels. The channels are advantageously made of concrete or asbestos cement and are preferably insulated on the outside. Means other than the lens itself can also be provided for condensing the vapor, such as, for example, essentially smooth, preferably flat plates, which are arranged below the lenses 164. In such a case, the lens liquid cannot recover substantially all of the latent heat unless the plate is placed near it. Alternatively, means cooperating with the plate can be used to recover the latent heat.

The device shown in FIG. 8 is essentially enclosed by the channel plates in order to reduce the heat losses 20. The plates are made of stretchable material so that the movement of the lenses can be absorbed. In addition, as already mentioned, the lens liquid is cooled by removing the recovered condensation heat, for example by recirculation in channels 25, which in turn cools the lower side of the lens and aids in the condensation of the vapor impinging thereon. As already described, the lens liquid is heated by direct and indirect absorption of infrared rays and by the heating of the lens plates, and this heat can also be recovered from the lens liquid. The heat recovered from the lens liquid and the condensed water can be used to preheat the water to be distilled before it enters the channel 166 or to preheat and heat the distilled water in the channel 166 by appropriate heat exchangers. The efficiency of the system can be further increased by recovering the heat contained in the brine drawn from channel 166 from time to time. The heat recovered from the condensing steam, condensed water, brine and lens liquid can be used for other purposes such as e.g. B. the generation of electricity by overheating and expanding liquids with low boiling points and heat of vaporization can be used. The water distillation systems described below operate in a similar manner and their description may therefore be more concise.

FIG. 9 shows an embodiment of a portable water distillation device 330 which can be easily assembled and disassembled. The device 330 comprises flat Fresnel lenses 126 with concentric microprisms, by means of which the solar energy can be concentrated in focal points. A longitudinal Fresnel lens or lenses can also be used. The lenses 126 are arranged next to one another in the longitudinal and transverse directions, so that there is a composite lens arrangement of 6 Fresnel lenses, which is inclined with respect to the horizontal and in which the 6 ((number 6 is only chosen for the sake of illustration. The lenses are thereby combined into one unit , because they are glued onto a glass or plastic plate 332, for example by adhesives, which allows solar energy to pass through and which, in the case of plastic, can be folded along flexible dividing lines 65 334. Each Fresnel lens can measure approximately 18 x 34 cm lie in the water to be distilled in the flexible container or sack 336, which is made of plastic or another foldable

9

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ren material. The flexible container or sack 338, as compared to irradiating it with unconcentrated plastic or other flexible material, is under light energy to gain while the increased heat is disposed within the container 336 and extends over gie dissipated and from the fluid media in the Line this out. It is used to remove the condensate from the plate. As already described, the 332 can be collected. The lens arrangement and the container 5 heat quantity generated by the photocells by absorption infra-are held by a support arrangement 340, the supporting red radiation in a liquid lens are reduced,

pairs 342, 344, a frame 346 and a base plate 348. This increases the efficiency of the photocells while encompassing. The supports can be swiveled at one end to which the requirements for heat dissipation frame 346 are attached at the same time, and at the other end are reduced by the collector. Set in the fluid exercises in the base plate 348. The supports can absorb heat absorbed by the medium in the lens, and can also be recovered in the ground or otherwise attached, if necessary, as previously mentioned. It can be used with no baseplate. The supports can be electronically stored for other purposes from the solar energy in order to generate the angle of inclination of the lens arrangement. For example, if a double collector set and the seasonal sun position is used with two fluid media, photo sequences can occur. The containers or sacks have side walls 350, 352, 15 cells installed in the manner just described and which extend up to the plate 332 in which electrical energy can be obtained, while in the manner already described to form a closed system - Thermal energy can be used for heating. In the side wall 352, on the lower side of the electricity obtained for electrolysis of plate, an opening is formed which allows the condensate to drain Na-den collector bag 338 in water and / or salt for the production of hydrogen. Display means such as antrium and chlorine are used. The hydrogen can be used to connect the bottom of the container to transparent tubes with carbon monoxide for the production of methanol or to 322, 324 to indicate the water levels in the containers with nitrogen for the production of nitrogen fertilizers and containers. The lens assembly, support assembly and other nitrogen products such as nitric acid and urea containers can be easily disassembled and used together. Such electrolysis can be put together with the. Which take place in the water to be distilled in the distillation arrangement. Furthermore, according to the focal points located 336, the water can heat up and, according to the invention, an electricity using solar energy can vaporize it, whereupon it condenses combi-plates 332 on the underside of the level extraction system with hydroelectric means. The condensate moves along the kidneys, which include water reservoirs. Such a com-den plates 332 and falls into the container 338. combination allows the generation of electricity at night

According to another aspect of the invention, the time during periods of reduced sunshine or during concentrated solar energy is used to generate electricity and consumption peaks through the hydroelectric device by means of photo elements. The photo elements 398 of the device while the solar energy system provides electricity during Fig. 10 are made of silicon or cadmium sulfide or other periods of sunshine. The solar energy system, its materials and are arranged in the interior of the inner liquid line, which can lead as an arrangement floating on the storage container, which advantageously is provided with a right-angle and therefore does not require an additional angular cross section. The theoretical focus land.

402 of the lens is located on the photocells and preferred- As already mentioned, in some cases it can be advantageous on its outer surface. The cells may be omitting the plate 46 which, according to FIG. 1, is used to form a row next to one another and also parallel to one another, forming a greenhouse effect in the collector when the theoretical burning point 402 detects a burning point becomes. The collector 205 of FIG. 11 does not include a plate line, or even at intervals if the theoretical 46 of FIG. 1, so that the heat of the infrared rays

Focus 402 is an actual focus. Which is not retained in the collector. The omission of light rays are converted from the cells into electricity by the plate 46 and the associated seals and reumbers, while the heat absorbed by the cells reduces the insulation, reducing the cost of the collector of infrared rays through the circulating liquid404 45, while that of the heat generated by the infrared rays and also by the liquid 406, which is distributed in the outer glue into the surroundings. In addition, the manure part is circulated, which is transported away. The heat transfer lines in the collector 205 of the sun via a large port can be exposed by the dimensioning of the lines 400, 408 and this angle.

by the volume and speed at which the fluid lenses with top and bottom plates are generally

fluid medium is circulated, controlled. Preferably 50 mean large and accordingly have a long focal mode, the fluid medium is essentially not electrically, which are usually longer than the width of the plates, is conductive, such as, for example, air or other gases and fluids. candy. Means, not shown, connect the photocells to the microprisms are generally smaller and have focal lengths that are shorter than one another in parallel or in series for stripping. Since the longitudinal direction of the generated electricity. If the fluid medium 404 5J microprisms decrease in height towards the center of the lens, is electrically conductive, means not shown for electrical are limited in the lens width. The width of the glass insulation of the cells and the means for connection or plastic plates for the Fresnel lenses is also limited. This pre-designed the cells and dissipation of the generated electricity can be used with great advantage. For example, hen. The conduit 400 is at least on its surface, the plate 46 (FIG. 1) can be omitted and yet the ge-made of transparent material, if the theoretical greenhouse effect is maintained by the distance between 402 being a line, it can Above the cells, the lenses and the collector can also be seen in a closed transparent opening. The upper part of the system is diminished.

outer lead 408 is also transparent. The details. FIG. 11 shows a combination of a fluid lens 200, which has already been described in the middle on the inner and outer lines, with four adjacent ones. ß Fresnel lenses 201 to 204, each of which has a profile,

As already mentioned, the concentration of the light - which is at such an angle that the sun's ray energy of the sun up to about a hundred times, electricity len on a common longitudinal burning - with up to a hundred times the power with the photocells, point 208, which is also the focal point of the central

626159

10th

represents fluid fluid lens. The lens system can be connected to the collector 205 and be movable in order to be able to follow the position of the sun in the manner described. The lens system can also include two Fresnel lenses instead of four. Also, the lenses can be arranged lengthways and crossways as in Fig. 5 to significantly increase the concentration of solar energy, especially for use in the generation of electricity using photo elements.

Lenses with a fluid medium are larger than Fresnel lenses, absorb less and reflect more solar energy than Fresnel lenses. Therefore, an assembly consisting entirely of lenses with a fluid medium is generally less effective than an assembly comprising only Fresnel lenses or at least one Fresnel lens in combination with at least one lens for a fluid medium. According to the invention, arrangements with Fresnel lenses and lenses containing a fluid medium are also specified. Such devices can be used to great advantage in the distillation of water, where the lenses containing a fluid medium increase the overall efficiency by recovering the heat of vaporization of the distilled water. Such a device 450 is shown in FIG. The device 450 comprises a fluid lens 22 and Fresnel lenses 132 A and 132 B. Each lens has a different focal point in the channel 166, which contains the water 170 to be distilled. The channel 166 is trough-shaped and has different water depths. The different focal points are located at different depths. A narrow Fresnel concentrator 132 A is arranged above the zone in the channel 166 into which the water to be distilled is introduced and which is designated 451. The lens 132 A serves to preheat the water introduced into the channel 166 to, for example, about 40 ° C. As a result, practically no condensation takes place at this point. The high efficiency Fresnel lens 132 B has a steep angle of inclination to the horizontal and faces north. It is focused on the inner line in the collector 172, which is of the two-line type. The collector 172 and the Fresnel lens 132 B are interconnected, and the lens is supported in the manner described in FIG. 1, so that both are movable in order to be able to follow the seasonal and hourly position of the sun. Flexible surfaces 452 are preferably provided and attached on one side to the support for the Fresnel lens 132 A and on the other side to the support arrangement for the fluid lens 22. The inner line 38 carries a liquid with a high boiling point, which can be heated to a high temperature of, for example, 200 ° C. This in turn heats the liquid with the low boiling point in the outer line, for example to 80 ° C. Because of its steep angle and because it is not cooled by a liquid like a liquid lens, little vapor condenses on lens 132 B. Liquid lens 22, which is less efficient than lens 132 B, is inclined at a small angle to the horizontal , for example by 15 °, and facing south, which is sufficient to allow condensate to flow along the lower plate 28 and drain into the channel 168. The lens 22 is focused directly into the channel 166, so that its focal point is located in the water 170 regardless of the seasonal and daytime position of the sun. A substantial portion of the vapor strikes the lens 22 because of its location. The Fresnel / liquid lens combination of Fig. 12 has the following advantages. By using several lenses, collectors and focal points in different water depths, the water is heated in different depths to different temperatures, so that

Use currents that support the overall heating of the water and the evaporation and thereby improve the efficiency of the system. The use of Fresnel lenses to heat the water while at the same time providing a liquid lens on which the vapor condenses allows the heat of vaporization to be recovered by the lens liquid while at the same time making it possible to use the more effective movable Fresnel lens. The liquid lens is not movable because a suitable angle of inclination must always be maintained so that the condensate can run off on the lower plate of the lens. The focal point of lens 22 is always in channel 166, regardless of the season.

The use of a collector 172 in the focal point of the 15 effective Fresnel lens and also the use of a liquid with a high boiling point allow the temperature of this liquid to be raised to approximately 200 ° C., as a result of which heat can be stored in the manner already described and used during the night . The arrangement of the focal point of the lens 22 directly in the channel heats the water quickly and supplies the water 170 with heat during the sunshine periods. During periods without sunshine (and also during periods of sunshine when heat is removed from the lens liquid) 25, the lens liquid is cool and causes more condensation of the vapor. This combination allows a continuous operation, the focal point of the lens 22 directly in the channel causing the evaporation of the water during the sunshine periods and the collector 30 gate 172, in which the liquids in the inner line to 200 ° C and in the outer line are heated to 80 ° C., stores heat and takes over the evaporation of the water during periods with and without sunshine, supported by the lower lens plate 28 cooled by the lens liquid.

A further embodiment for distilling water, which is similar to the device according to FIG. 12, is shown in FIG. 13. However, two sets of double-lens liquid lenses are provided in FIG. A lens set 22 A 40 is inclined to the south by, for example, 15 ° to the horizontal and has a smaller distance between the plates of, for example, 2.5 cm at the point of greatest distance. Such lenses have sloping, cooled base plates so that the steam condenses 45 on these plates and can flow off against the channel 168 and run off therein. Another set of lenses 22 B contains a rotating lens liquid with a boiling temperature of preferably above 200 ° C. and high infrared absorption. This liquid is introduced from the lens arrangement into the inner line 38 of a series of preferably metallic, interconnected collectors 172, 172 A, 172 B, 172 C. A number of interconnected collectors are provided in channel 166 to increase the total collector surface area. The inner 55 lines 38 are inserted into the outer 36. Another liquid, such as. B. water flows in the outer lines 36 around the line 38. The liquid circulated in the line 36 is heated to, for example, 90 ° C. and heats the water 170 contained in the container 166. 60 The flow of the high-temperature liquid in the lines 36 is interrupted in the hours without sunshine. The high temperature liquid is stored in the inner lines 38 and continues to heat the liquid in the outer lines 36. The outer lines 36 in turn heat the water so that it can be distilled further in the sunless hours. The lenses 22 A with the cooled lower plates 28 condense the water vapor thus produced

Claims (14)

626159 1. A device for converting concentrated solar energy into heat, with a device for concentrating solar energy, characterized in that an at least two elongated lines (36, 38) for fluids are included- 5 the collector (24) is present that the two lines (38, 36) are arranged such that the first line (38) for guiding the first fluid (56) is surrounded by the second line (36) for guiding the second fluid (54) such that the second line is at least partially transparent that the 10 fluids in the inner and outer conduits are in a heat exchange relationship and that the transparent part of the outer conduit (36) is oriented so that solar energy gets into it through the transparent part of the outer conduit, the area of the concentrating - 15th solar energy extends substantially on or in and substantially along the length of the inner conduit. 2. Device according to claim 1, characterized in that the inner line (38) is at least partially transparent. 20th 2nd PATENT CLAIMS 3. Device according to claim 1 or 2, characterized in that the concentration device comprises an elongated lens arrangement (22; 80, 132). 4. Device according to claim 3, characterized in that the lens arrangement contains at least one elongated Fresnel lens (132; 201) and / or at least one elongated liquid lens (22; 80) with a longitudinal axis running essentially parallel to the longitudinal axes of the two lines , and that the lens is arranged in such a way that the solar energy is concentrated through the transparent parts of the outer and, if appropriate, inner lines, along the focal line of the lens running essentially on or within the inner line. 5. Device according to one of claims 1 to 4, characterized in that one fluid is present in each line 35 and the two fluids are of the same nature or different fluids. 6. Device according to one of claims 1 to 5, characterized in that the collector (24) comprises an elongated container (40), that said lines are arranged in 40 the container, that the container is aligned with the transparent parts of the lines Has opening (44) for transmitting solar energy to the lines. 7. Device according to claim 3, characterized in that 4S that within the inner line (400) photo elements (398), e.g. B. of silicon or cadmium sulfide are arranged that at least parts of the concentrated solar energy hit the photo elements. 8. The device according to claim 7, characterized in that the lens arrangement contains at least one elongated liquid lens (22), that the photo elements are arranged along the focal line of the liquid lens and that the liquid lens contains a liquid which transmits visible radiation essentially unimpeded and infrared J5 absorbs radiation, which reduces the heating of the photo elements by solar radiation and increases the efficiency of the photo elements. 9. Device according to one of claims 3 to 8, characterized in that heat exchange means for removing the heat from the liquid of the liquid lens and pipes (64) for guiding the liquid into and out of the liquid lens are present. 10. Device according to one of claims 3 to 9, characterized in that means (55, 58, 70) for pivoting the lens about at least one axis for tracking the lens are present daily and / or seasonal changes in the position of the sun. 11. Device according to one of claims 1 to 9, characterized in that it can be dismantled to facilitate assembly and disassembly into portable parts. 12. Use of the device according to claim 1 for distilling a liquid containing water, characterized in that there is a container (166) for receiving the liquid to be distilled, that said lines (36, 38) are arranged in the container that optical Means (224, 228) for concentrating solar energy in the container are arranged above the container such that an elongate element (28) which is at least partially transparent to sunlight and having a substantially smooth surface area is arranged above the container, that the smooth surface region is in relation to a horizontal plane for guiding the condensate to a lower part of the element and that a collecting means (168) for collecting the condensate is arranged under the lower part of the element. 13. Use according to claim 12, characterized in that the optical means have at least one liquid lens (224), that the liquid lens through the elongated element (28), a transparent lens plate (26) and a liquid enclosed between the element and the lens plate ( 31), the elongate element for releasing the heat of condensation to the lens liquid is arranged on the underside of the liquid lens, and means (177) for supplying and removing the lens liquid into and out of the liquid lens are provided. 14. Use according to claim 12 or 13, characterized in that a plurality of elongated lenses are arranged so that the focal line of some of these lenses run at different depths of the liquid to be distilled in the container.