Salt power plant

Abstract

The invention relates to a salt power plant based on a potential difference between in-flowing water and a highly concentrated salt solution. The salt power plant has an in-flow chamber, a pre-chamber located between the inflow chamber and a pressure silo, wherein the pressure silo can be pressure-tightly closed apart from its fluidic connection to the pre-chamber. There is an in-flow valve between the in-flow chamber and the pre-chamber. The salt power plant also has an osmosis membrane unit which is located within the pressure silo and lies between the pre-chamber and an interior of the pressure silo. The pressure silo and the osmosis membrane unit can be filled with pourable salt, and in a pressure-producing state the osmosis membrane unit lies below a water level of the in-flowing water. The pressure silo is filled with the salt solution, and the fluidic connection is filterless from the water inlet, via the inlfow chamber and the pre-chambers, up to the osmosis membrane unit. An outlet connection is provided in an upper region of the pressure silo.

Description

DESCRIPTION SALT POWER PLANT Field of the invention

[0001] The invention relates to a salt power plant, and more specifically to a salt power plant based on potential differences between incoming water of varying qualities. The increasingly scarce resource of freshwater is not a mandatory requirement, since the inflow of seawater or wastewater on the one hand and a saline solution of the highest possible concentration on the other hand are considered advantageous and sustainable. The invention further relates to a method for operating a salt power plant. Technical background

[0002] Alternative, future-oriented and, in this context, CO2 emission-neutral energy generation has been gaining increasing importance for some time now. In addition to the various prototypes for energy generation using, for example, ocean wave and tidal energy, wind turbines and solar systems - particularly photovoltaics and solar thermal energy - are increasingly becoming the focus of interest. The current designs of the developments available for energy generation using osmosis systems are not yet sufficiently effective and usually require access to both freshwater - e.g., river deltas - and seawater for operation. In addition, these systems require access to existing industry-typical infrastructure, such as a connection to existing or future power grids. In addition, the overall efficiency of these systems is significantly reduced by the inevitable use of complex pre-filter and fine filter systems.This is because the osmosis membrane designs currently in use can only achieve a reasonable service life when exposed to the purest water.

[0003] In addition, all these systems require electronic sensor and computer systems that are vulnerable to both cybercrime and EMPs (electromagnetic pulses) - for example, those caused by solar flares - which can lead to energy shortages in times of crisis.

[0004] Another disadvantage of existing systems is that not all of the solar energy radiated per square meter can be utilized without the use of costly and maintenance-intensive photovoltaic or solar thermal systems. Furthermore, existing systems lack a link between energy generation and drinking water production, especially when salt or wastewater is used to operate the osmosis power plant.

[0005] Another disadvantage of the approaches to osmosis systems known to date is that they often require the infrastructure and operational know-how typical of industrialized countries to operate these systems efficiently. On the other hand, practically only systems designed for low energy generation are available.

[0006] Thus, there is a need to address the shortcomings of existing solutions and, in particular, to provide an osmosis system for energy generation on a larger scale without the need for complex infrastructures and operational know-how. OVERVIEW OF THE INVENTION

[0007] This object is achieved by the salt power plant proposed here and the corresponding method for its operation according to the independent claims. Further embodiments are described in the respective dependent claims.

[0008] According to one aspect of the present invention, a salt power plant based on a potential difference between inflowing water on the one hand and a salt solution on the other is presented. The salt power plant comprises a first inflow chamber with a water inlet and a first pre-chamber located between the first inflow chamber and a first pressure silo. The first pressure silo should be pressure-tightly sealable except for its fluid connection to the first pre-chamber.

[0009] Furthermore, the salt power plant has at least one first inlet valve arranged between the first inflow chamber and the first pre-chamber, so that the first inflow chamber is fluidically separable from the first pre-chamber, and a first osmosis membrane unit located within the first pressure silo and between the first pre-chamber and an interior of the first pressure silo. The first Osmosis membrane unit removable from the interior of the first pressure silo in a direction opposite to a direction toward the first prechamber.

[0010] Furthermore, the first pressure silo and the first osmosis membrane unit can be filled with free-flowing salt, and the first osmosis membrane unit is located in a pressure-producing state below a water level of the incoming water. Furthermore, the first pressure silo can be filled with the salt solution.

[0011] Furthermore, the fluid connection from the water inlet via the first inflow chamber and the first pre-chamber to the first osmosis membrane unit in the salt power plant is filterless. Additionally, a first outlet connection may be provided in an upper area of ​​the first pressure silo.

[0012] According to a further aspect of the present invention, a method for operating the aforementioned salt power plant is presented. The method comprises filling the first pressure silo with free-flowing salt through the first upper, hermetically sealable opening of the first pressure silo so that the first osmosis membrane unit is completely covered with the salt, as well as venting the first pressure silo and opening the first outlet connection.

[0013] Furthermore, the method comprises opening the at least first inlet valve so that a continuous water flow into the first prechamber is caused.

[0014] The proposed salt power plant based on a potential difference between incoming water on the one hand and a salt solution on the other hand has several advantages and technical effects that can also apply to the associated system:

[0015] The proposed system—that is, the salt power plant—can be very low-maintenance and can therefore be advantageously deployed in regions with poor infrastructure. This includes, but is not limited to, coastal areas of non-industrialized countries. However, it is also possible to deploy the proposed salt power plant near a salt mine inland, provided sufficient inflowing water is available.

[0016] Because the salt power plant requires little maintenance and has few moving parts, it can be easily operated by unskilled workers. The salt power plant itself can serve as a nucleus for other infrastructure, as no external power supply is required. Necessary components such as pumps, controls, and valves can preferably be operated hydraulically. Alternatively, or in a mixed operation, the required units can also be powered by electricity. This can be generated by a generator connected to the salt power plant.

[0017] In contrast to other approaches, a characteristic of the system is that the salt brine is formed directly above the osmosis membrane. Initially (i.e. during the start-up phase), the salt can lie in crystalline form on the osmosis membrane or osmosis membrane unit, whereby a saturated salt solution lies directly on the membrane surface. The water diffusing in from the pre-chamber dilutes the existing salt solution and rises due to its lower density and subsequently, once the power plant has started up, due to the flow conditions in the pressure silo. The inflowing water generates the pressure necessary for the operation of the salt power plant. The osmosis membrane itself or the space directly above it can be designed to create the smallest turbulence in the flow path without unduly hindering the overall flow. This mixes the brine and permeate more quickly and improves the effectiveness of the osmosis process.In addition, the durability of the osmosis membrane can be increased, for example, through local cross-currents on the osmosis membrane.

[0018] After start-up, a dynamic flow equilibrium is finally established, during which the salt content of the brine can rise close to the solubility limit. In this case, the maximum possible pressure in the pressure silo was achieved at the lowest flow rate.

[0019] As soon as the brine concentration in the pressure silo drops, the flow rate inevitably decreases at constant pressure, causing the dissolved salt quantity and thus the concentration to rise again. The system thus regulates itself once the desired ratio between pressure and flow rate has been defined—for example, via a valve.

[0020] Further advantages of the salt power plant include the following: No freshwater is required to start up the salt power plant, as the plant generates all the necessary resources itself, or these are already available (seawater, solar energy), and no external infrastructure in the form of electricity, gas, or freshwater is required. Filter systems are also not required, which keeps operating and maintenance costs low. Furthermore, a pumping infrastructure is not required. This is because no filters are required for the flow. Complex turbines such as Pelton, Kaplan, or Francis turbines are not required for power generation. The simplest technologies are sufficient. Initial energy (fossil, nuclear, wind, solar) for start-up is also not required. Complex and failure-prone control electronics are eliminated, meaning that the salt power plant, with appropriate design, is protected against cyberattacks, preventing energy security from being compromised in this way.

[0021] Furthermore, the salt power plant can be operated by semi-skilled personnel without the need for advanced training. Furthermore, the salt power plant is carbon dioxide-neutral during operation. Furthermore, no significant waste products, such as filter material, electronic waste, toxic substances, etc., are generated during recycling, further contributing to a cost-effective and sustainable overall approach and to low reprocessing and disposal costs.

[0022] It's also worth mentioning that the proposed salt power plant can be used regardless of climate. If solar energy is insufficient to dry the "used" salt, vacuum evaporators, for example, can also be used. These would have the additional advantage that the pure water introduced into the system cycle by the osmosis membrane unit could be used for beneficial purposes – for example, as industrial or drinking water. Furthermore, the salt power plant is fully scalable. It operates not only on a small scale but also allows for large-scale deployment. In micro-plants in arid and semi-arid regions, simple evaporation systems – such as saline basins – can be used to regenerate the salt.

[0023] It should also be mentioned that the salt power plant can be adapted, even in its smallest form, so that it can be used, for example, for the production of hydrogen in small businesses or individual households (single-family homes or apartment blocks). This could produce hydrogen for direct consumption or for fueling vehicles (family cars, bus companies) or even for heating systems, thus providing operators with a self-sufficient supply. Likewise, ship propulsion and salt-powered engines for pier cranes and similar devices would be feasible. In the future, a suitably adapted salt power plant could even be conceivable for space travel (e.g., water supply for lunar stations).

[0024] Depending on the location, such as arid and semi-arid areas, the entire solar energy radiated per square meter can be used without the use of costly and maintenance-intensive photovoltaic systems or solar thermal systems. This does not mean that that the separation of salt from the water in the brine cannot also be achieved in parts of the world with temperate climates through the use of targeted (e.g., vacuum) evaporation systems or other advantageous evaporation combinations. A remarkable feature of suitable evaporation systems in the variously designed evaporation systems is that the ultrapure water originally extracted from the sea through an osmosis membrane unit can consequently be obtained as a (by- or main) product. If this water is used for irrigation (in addition to possible treatment by adding relevant minerals to drinking water), particularly in arid and semi-arid agricultural regions, the salinization of these areas, which is currently common, can be prevented. For example, the waters currently used – for example, in the Arab region – often have conductivity values ​​between 300 pS and 500 pS, which inevitably leads to soil salinization.

[0025] Because clean water can be produced from seawater or wastewater as a by-product or as a primary product, depending on the evaporation system, it is possible for large-scale salt power plants to produce biomass on a large scale, which in turn binds CO2. Thus, salt power plants are not only CO2-neutral but can also act as CO2 sinks.

[0026] Thanks to the modular design of the salt power plant, its size can be easily adapted to specific requirements. Small and micro-salt power plants can be designed to serve small, remote villages, operated by the residents, or as very large plants to supply entire regions.

[0027] The innovative basic concept of the salt power plant is deliberately not designed as a high-tech concept, but rather, its construction and design are comparatively inexpensive. It was designed to be simple, low-cost, easy to operate, and maintain. Furthermore, all components are recyclable.

[0028] Further embodiments are described below.

[0029] According to an advantageous embodiment of the salt power plant, the first osmosis membrane unit can be arranged substantially horizontally, and the first osmosis membrane unit can have a surface area that is at least ten times larger than a cross-section of a direct fluid connection between the first pre-chamber and the interior of the first pressure silo. Since the size of the osmosis membrane surface has a significant influence on the energy conversion of the salt power plant, special It is advantageous to take precautions that allow the effective surface area between the low-salt water in the pre-chamber and the high-salt water in the pressure silo to be as large as possible, but in particular significantly larger than a direct physical connection between containers containing water with different salt concentrations. In a real-life case, the first osmosis membrane unit may well have a surface area that is between ten and 100 times larger than the cross-section of the direct fluid connection between the first pre-chamber and the interior of the first pressure silo; it may be even larger, for example, 200, 300, or more.

[0030] According to a further advantageous embodiment of the salt power plant, the first osmosis membrane unit can have a substantially funnel-shaped support structure, and a first osmosis membrane can be located above the funnel-shaped support structure in order to have a larger surface area than the cross-section of the direct fluid connection between the first pre-chamber and the interior of the first pressure silo. The first osmosis membrane can be laid, stretched, or otherwise secured in a meandering manner over the substantially funnel-shaped support structure. Furthermore, it is possible for the support structure and the osmosis membrane to be integrated into one another, i.e., for the support structure to be formed equally by the osmosis membrane, resulting in a self-supporting structure—i.e., a self-supporting osmosis membrane with a much larger surface area than the clear passage in which it is inserted.

[0031] According to another, alternative but nevertheless advantageous embodiment of the salt power plant, the first osmosis membrane unit can have a support structure in which a plurality of tubular individual osmosis membranes arranged parallel to one another can be arranged. This has the advantage of particularly high inherent stability, in which a funnel-shaped structure is not absolutely necessary. The tubular individual osmosis membranes, which are combined into a unit, result in a very large surface area, which can be considered a self-supporting structure. Nevertheless, the individual osmosis membranes can not only be arranged directly next to one another, resulting in a box-like structure, but the tubular membranes can also be arranged in such a way that they form virtually any desired surface shape through the entirety of all ends of their respective tubes.Surrounding a core osmosis membrane unit, which essentially comprises the osmosis membrane including the support structure, with a support frame, e.g. in the form of a surrounding border, can help to ensure that the osmosis membrane unit can be easily removed from the lower part. The pressure silos are to be removed or reinserted. Holding points or retaining brackets may also be attached here (see Fig. 4).

[0032] According to a supplementary, advantageous embodiment of the salt power plant, the interior of the first pressure silo can be filled with salt through a first upper, hermetically sealable opening of the first pressure silo. If necessary, the osmosis membrane can be removed and replaced with a new one through this or another hermetically sealable opening. If such a replacement is not necessary, salt can be added to the first pressure silo through the upper, hermetically sealable opening—for example, in the form of a large, outwardly opening—in order to simplify the concentration gradient between the two sides of the osmosis membrane. Furthermore, it is possible for the first silo to be emptied through the aforementioned opening or another opening, allowing the osmosis membrane unit to be easily replaced.The replaced osmosis membrane unit is then reprocessed and is thus available for its next use.

[0033] According to a further developed embodiment, the salt power plant can have a second inflow chamber, which is fluidically separable from the first prechamber by a second inflow valve. If both inflow chambers - in particular the first and second inflow chambers - are located on different sides below the first prechamber, an inflow channel can be created which has the first prechamber as an integral part. In this way, it is possible to generate a higher water throughput of water with a low salt content - for example, seawater - which could increase the effectiveness of the salt power plant. In the event that there is only a low water throughput in the first prechamber, the salt content in the prechamber could continuously increase (due to insufficient water exchange), which would result in the osmosis pressure in the first silo decreasing over time.

[0034] According to an extended embodiment, the salt power plant can have a second pre-chamber located between the first inflow chamber and a second pressure silo, wherein the pressure silo can be pressure-tightly closed except for its fluid connection with the second pre-chamber.

[0035] In this or another embodiment, at least one second inlet valve, which is arranged between the first inflow chamber and the second pre-chamber, so that the first inflow chamber is fluidically separable from the second pre-chamber - in particular the respective interior - and a second osmosis membrane unit can be provided. which is located within the second pressure silo and which can be located between the second pre-chamber and an interior of the second pressure silo. The second osmosis membrane unit can be removable from the interior of the second pressure silo in a direction opposite to a direction toward the second pre-chamber.

[0036] Additionally—in this or another embodiment—the second pressure silo and the second osmosis membrane unit can be filled with free-flowing salt; and the second osmosis membrane unit, in a pressure-producing state, should be below a water level of the inflowing water. Furthermore, the second pressure silo can be filled with the salt solution. The fluid connection from the water inlet via the first inflow chamber and the second pre-chamber to the second osmosis membrane unit can be filterless. Furthermore, a second outlet connection—e.g., in the form of a pipe connection with a shut-off valve—can be provided in an upper region of the second pressure silo. Thus, the intake chamber, the pre-chamber, and the second osmosis unit can be fluidly connected to one another in this order.

[0037] In particular, eliminating the need for a filter system that is normally present can effectively prevent so-called overconcentration—that is, a continuous increase in salt concentration. In addition, a filterless design is mechanically simpler and requires less maintenance. Furthermore, the initial energy costs—that is, the energy required to initiate the osmosis process—are completely eliminated.

[0038] According to another elegant embodiment of the salt power plant, a pressure-tight, closed fluid connection can additionally be provided between the first outlet connection and a salt power plant that converts excess pressure in the first pressure silo into kinetic energy—e.g., rotational energy. The same applies to the second pressure silo.

[0039] This makes it possible to elegantly store the energy generated by the salt power plant as potential energy during idle times using pumps that can be driven by the salt power plant. This is possible, for example, by pumping water from a lower level to a higher basin, allowing the kinetic energy from the salt power plant to be stored as potential energy. This is possible with both the first pressure silo and the second pressure silo.

[0040] According to a supplementary embodiment of the salt power plant process, the salt power plant can be a single-stroke piston engine, a double-stroke piston engine, or a turbine. Other alternative simple power machines are conceivable, for example, to drive a generator for electricity production or for electrolysis, which in turn can be used to produce hydrogen. In this way, even in previously undeveloped regions, energy generation for any type of use could be elegantly installed. It would be powered solely by solar energy and salt from the sea, making it cost-effective to operate. Furthermore, minimal maintenance would be required, practically limited to the regular replacement of the osmosis membrane.

[0041] To further increase the degree of autonomy of the salt power plant, an automatic or semi-automatic feeding system for the salt from the pressure silo can also be provided.

[0042] According to a further embodiment, the salt power plant can additionally have a first venting unit connected to the first pressure silo and / or a second venting unit connected to the second pressure silo. Such venting systems can advantageously be provided in an upper area of ​​the pressure silo. Since it is advisable for trouble-free operation of the salt power plant if there is no air, but only salt solution, in the pressure silo, the venting units should be located as high up on the pressure silo as possible – possibly even directly at the uppermost point of the outlet connection. The same applies to the second pressure silo.

[0043] In one possible embodiment, the vent valve of the venting unit is located in a pressure-tight, lockable slide valve of the pressure silo. This allows the system to be effectively vented – possibly fully automatically.

[0044] According to a further, supplementary embodiment, the salt power plant can additionally have an evaporation unit that collects the salt solution leaving the salt power plant. In the evaporation unit, the used salt can be regenerated from the concentrated salt solution. After more or less thorough drying, it is then available again for filling the pressure silo. A particularly positive aspect is that the entire energy input can be used to operate the power plant, utilizing the total solar energy incident per square meter. Additional external energy would not be required.

[0045] According to an interesting embodiment of the salt power plant, the first inflow chamber at the water inlet can have one or more gratings arranged in different spatial directions. Preliminary and main gratings are conceivable, which are essentially vertically oriented. These gratings can be cleaned by one or more tidal cleaners. A scraper is guided along the grating so that the grating is automatically cleaned. For this purpose, the scraper can be moved by means of a float that follows the tides and a corresponding guide, as is conceivable according to another embodiment of the salt power plant. As mentioned, the tidal cleaner can have a float and a scraper, which can be mechanically connected to one another such that the scraper can be guided over an outer surface of the grating according to a tide-dependent water level, thus causing the grating to be cleaned.In addition, joints, articulated rods and gears can be used between the scraper and the float.

[0046] A few embodiments regarding operation—or a corresponding method—are also explicitly mentioned. The aforementioned method can additionally include parallel or alternating operation of the first pressure silo and the second pressure silo in a pressure-generating state.

[0047] According to one embodiment of the method for operating a salt power plant, the method may include filling the first pressure silo with free-flowing salt through the first upper, hermetically sealable opening of the first pressure silo so that the first osmosis membrane unit is completely covered with the salt, venting the first pressure silo, opening the first outlet connection, and opening at least the first inlet valve to cause a continuous flow of water into the first prechamber. This sequence allows the osmosis power plant to be restarted with a pressure silo after a supplementary salt filling.

[0048] In particular, the following can be advantageous when operating two pressure silos alternately: (i) operating two pressure silos in parallel, (ii) closing at least one first inlet valve, (iii) closing the first outlet connection, (iv) opening the first closable opening of the first pressure silo, and (v) filling the first pressure silo with salt through the first upper, hermetically sealable opening of the first pressure silo. Pressure generation in the second pressure silo continues uninterrupted. Once the first pressure silo has been returned to productive use, the second pressure silo can be refilled with salt, etc. Advantageously, more than two pressure silos can also be used in parallel.

[0049] According to a further supplementary embodiment of the method, the first osmosis membrane unit can be replaced via the first upper, hermetically sealable opening of the first pressure silo. This can be done during filling with salt. The same applies to the second osmosis membrane unit in the second pressure silo.

[0050] By means of a suitable sequence of closing and opening gates and valves on the two pressure silos as well as the water inlet, a more or less continuous operation of a salt power plant can be achieved, which can be used, for example, to generate electricity.

[0051] OVERVIEW OF THE CHARACTERS

[0052] It should be noted that embodiments of the invention may be described with reference to different implementation categories. In particular, some embodiments are described with reference to a method, while other embodiments may be described in the context of corresponding devices. Regardless of this, a person skilled in the art will be able to recognize and combine possible combinations of the features of the method, as well as possible combinations of features with the corresponding system, from the above and following descriptions—unless otherwise indicated.

[0053] Aspects already described above as well as additional aspects of the present invention result, inter alia, from the described embodiments and from the additional further concrete embodiments described with reference to the figures.

[0054] Preferred embodiments of the present invention are described by way of example and with reference to the following figures: Fig. 1 shows a cross-sectional view of an embodiment of the salt power plant according to the invention based on a potential difference between inflowing water on the one hand and a salt solution on the other hand. Fig. 2 shows a cross-sectional perspective view of a first pressure silo in combination with a corresponding second pressure silo. Fig. 3 shows the osmosis membrane unit in greater detail. Fig. 4 shows a detailed view of the lower part of a pressure silo. Fig. 5 shows a method for operating a salt power plant. Fig. 6 shows a method for operating a salt power plant with two pressure silos. Fig. 7 schematically shows various possible applications of the salt power plant. Detailed character description

[0055] In the context of this description, conventions, terms and / or expressions should be understood as follows:

[0056] The term 'salt power plant' describes an energy generation system that operates on the basis of osmotic pressure differences. A more or less continuously flowing water is directed to a first (lower or outer) surface of an osmosis membrane, on the other (upper or inner) surface of which a highly concentrated salt solution is present. This results in an osmotic flow of water through the osmosis membrane, creating an overpressure on the side of the membrane where the highly concentrated salt solution is present. This pressure can be converted from pressure energy into rotational energy, for example, in a power plant.

[0057] The term 'incoming water' here refers to water with a low or no salt concentration, which is fed to the first side of the osmosis membrane. In the case of seawater, the feed can occur autonomously, particularly through the normal seawater flow near the coast.

[0058] The term 'salt solution' essentially refers to the contents of a pressure silo. Large quantities of salt are poured into it, resulting in a highly concentrated salt solution. This solution is in contact with one of the surfaces—specifically the upper one—of the osmosis membrane.

[0059] The term 'first inflow chamber' describes the chamber into which inflowing water first enters. The inflow can be directed through an inflow grate (not shown). At the outlet of the first inflow chamber, a pre-chamber of the salt power plant can be connected. The pre-chamber can be connected to a second inflow chamber on at least one second side. This creates an inflow channel consisting of the first inflow chamber, the second inflow chamber, and the pre-chamber in between. If the pre-chamber is round or semi-round (instead of rectangular), the first inflow chamber and the second inflow chamber can at least partially merge into one another. In this case, a round or semi-round inflow gate would be suitable to seal off the pre-chambers from the inflow chambers.

[0060] The term 'pre-chamber' describes the part of the water flow path into or through the salt power plant that lies directly before the osmosis membrane unit. From here, the water flows under osmotic pressure through the osmosis membrane into the pressure silo.

[0061] The term 'pressure silo' describes a cavity that can be closed on all sides and is interrupted only at (at least) one point by an osmosis membrane – e.g., in the lower section. The osmotic pressure can escape from the pressure silo through a sealable outlet opening.

[0062] The term 'fluidal connection' describes a connection between cavities through which a fluid can flow more or less barrier-free. This may also include the presence of an osmosis membrane within the fluid connection.

[0063] The term 'inlet gate valve' here describes a bulkhead that can separate an inlet chamber from the pre-chamber when closed.

[0064] The term 'fluidally separable' here describes that the flow from one cavity to another can be deliberately interrupted. That is, the fluid connection can be interrupted.

[0065] The term 'osmosis membrane unit' describes a unit that has at least one osmosis membrane. Additionally, the osmosis membrane unit may have a support structure on which the osmosis membrane is located. The osmosis membrane may, for example, be laid or stretched in a meandering pattern over a meandering support structure. Alternatively, the osmosis membrane unit may also comprise a plurality of tubular Osmosis membranes are more or less self-supporting. In addition, the osmosis membrane unit has a common support frame that allows the entire osmosis membrane unit to be moved, for example, to replace it with a new or refurbished osmosis membrane unit in a pressure silo. The osmosis membrane essentially allows only pure water to flow from the pre-chamber into the pressure silo.

[0066] The term 'funnel-shaped support structure' describes that the support structure in question - at least in the lower area of ​​the support structure - is funnel-shaped, so that the free-flowing salt continuously slides into the osmosis membrane unit.

[0067] The term 'free-flowing salt' describes salt in a crystalline state, meaning it is pourable or free-flowing. Typically, this salt is NaCl. However, admixtures of other salts or completely different salts are also conceivable.

[0068] The term 'pressure-producing condition' here describes the development of overpressure in a pressure silo due to different salt concentrations on different sides of the osmosis membrane used and a water inflow from the pre-chamber into the pressure silo. This overpressure can be released from the pressure silo through an outlet connection for further use.

[0069] The term 'outlet connection' is typically, but not necessarily, located at the top of the pressure silo. Water can be released from the pressure silo through the outlet connection based on the osmotic pressure within the pressure silo. This water can then contain a high salt concentration.

[0070] A detailed description of the figures is provided below. It should be understood that all details and instructions in the figures are shown schematically. First, a flowchart-like representation of an embodiment of the salt power plant according to the invention based on a potential difference between incoming water on the one hand and a salt solution on the other hand is presented. Further embodiments, or embodiments for the corresponding salt power plant and methods for operating the same, are described below:

[0071] Fig. 1 shows a cross-sectional view of an embodiment of the salt power plant 100 according to the invention based on a potential difference between inflowing water on the one hand and a salt solution on the other hand.

[0072] The quality and composition of the incoming water can vary widely. In principle, water of various qualities is possible, such as brackish water, fresh water, polluted water, or even seawater with a comparatively low salt concentration. The salt solution in the pressure silo is preferably a saturated or highly concentrated salt solution. The salt can be naturally occurring salt, such as NaCl, although it does not necessarily have to be in pure form. Salt mixtures are therefore also possible.

[0073] The salt power plant 100 has a first inflow chamber 102 with a water inlet 104. This can be equipped with a preferably vertical grating and a tidal cleaner. Furthermore, the water inlet should be constantly below a surrounding water level 120 (symbolically shown) – regardless of whether the tide is low or high, and whether the tide is high or low.

[0074] The salt power plant 100 also has a first prechamber 106. Filters can optionally be provided in the prechamber. However, they are not absolutely necessary. The filters can be sand filters and / or other pre-filter modules of varying fineness / mesh. The prechamber 106 is located between the first inflow chamber 102 and a first pressure silo 108. In this exemplary embodiment, the prechamber 106 is shown below the pressure silo 108. Other positioning—such as a lateral positioning at the lower end of the pressure silo 118—is also conceivable. The pressure silo itself—viewed from above—can be rectangular, round, or even semicircular. A specific shape is not mandatory. However, the lower part of the pressure silo 108 should be designed such that an osmosis membrane unit 114 can be removably accommodated.It is advantageous that the first pressure silo 108 can be closed pressure-tight (airtight and watertight) except for its fluid connection 110 with the first prechamber 106.

[0075] The salt power plant 100 additionally has at least one first inlet valve 112, which is arranged between the first inlet chamber 102 and the first pre-chamber 106, so that the first inlet chamber 102 is fluidly separable from the first pre-chamber 106. If—as shown in Figure 1—a second inlet chamber 128 is present, a second inlet valve 130 should also be provided. It should also be noted that the inlet chambers 102, 128 should advantageously be closed at the top and bottom. The advantage of the second inlet chamber 128 with a second water inlet is that the pre-chamber 106 is much better flushed by incoming water. can be carried out without causing an increase in salt concentration in the pre-chamber 106, if, for example, sea water is used as the inflowing water.

[0076] The power plant 100 further comprises a first osmosis membrane unit 114, which is located within the first pressure silo 108 and lies between the first pre-chamber 106 and an interior space 116 of the first pressure silo 108, wherein the first osmosis membrane unit 114 is removable from the interior of the first pressure silo 108 in a direction opposite to a direction toward the first pre-chamber 106. In particular, the osmosis membrane unit 114 can be removed from the pressure silo 108 upwards through the pressure-tightly sealable flap 126. However, this requires that the salt normally present in the interior 116 of the pressure silo 108, e.g., in the form of an aqueous solution, has been largely drained from a lower region of the pressure silo.

[0077] For productive, pressure-generating operation, the first pressure silo 108 and the first osmosis membrane unit 114 can be filled with free-flowing salt. For this purpose, the first pressure silo 108 is typically filled with salt from above via the closable opening 126, so that the pressure silo 108 is largely filled with salt, which also rests directly on the osmosis membrane unit 114.

[0078] Thus, in an operating or pressure-producing state, the first osmosis membrane unit 114 lies below the water level 120 of the incoming water, and the first pressure silo 108 is largely or completely filled with the—preferably saturated—salt solution. It is also advantageous that no air or other gas is present in the pressure silo 108.

[0079] A further advantage that has been advantageously demonstrated during operation is that the fluid connection 110 from the water inlet 104 via the first inflow chamber 102 and the first pre-chamber 106 to the first osmosis membrane unit 114 is filterless. This can significantly reduce the risk of concentration upstream of the osmosis membrane unit 114, is structurally simpler, generates lower maintenance costs, and also enables a reduction in the required initial energy costs to put the salt power plant 100 into productive operation.

[0080] In order to utilize the excess pressure from the interior 116 of the pressure silo 108, a first outlet connection 122 - e.g., a pipe connection with a shut-off valve - is provided in an upper area of ​​the first pressure silo 108. From here, it can be connected, for example, to a salt power machine or salt power plant (not shown) for conversion into kinetic, For example, rotational energy can be converted. This can drive an electric generator, whose electricity can be used for a variety of different applications. One of these would be the production of hydrogen through electrolysis.

[0081] It should also be noted that the effective surface area of ​​the osmosis membrane of the osmosis unit is at least 10 times larger than a cross-section 124 of the direct fluid connection between the first pre-chamber 106 and the interior of the first pressure silo 108. However, the ratio of cross-section to surface area can also be much larger, e.g., 1:100 or even 1:1000. This can be achieved, among other things, by the first osmosis membrane unit 114 having a substantially funnel-shaped support structure (as shown in Fig. 3), and a first osmosis membrane being located above the funnel-shaped support structure, so as to have a larger surface area than said cross-section 124 of the direct fluid connection between the first pre-chamber 106 and the interior of the first pressure silo 108.

[0082] Fig. 2 shows a cross-sectional, perspective view of a first pressure silo 108 with the first pre-chamber 106 and the other details already described in Fig. 1, as well as a second pressure silo shown in the rear area of ​​Fig. 2 with associated additional components, which are not all visible in the perspective view, but are provided symmetrically to the first pressure silo 108.

[0083] It can be seen here that the first inflow chamber 102 and the second inflow chamber 128 can be used for both the first pressure silo 108 and the second pressure silo 208, or the two associated pre-chambers. Otherwise, the two pressure silos 108 and 208 can be constructed more or less symmetrically. Also clearly visible is the pressure-tight, sealable opening 226 of the second pressure silo 208, above which an exchange osmosis membrane unit 214 is shown. This can be inserted into the second pressure silo 208 through the opening 226 in the event of a necessary replacement.

[0084] The two pressure silos 108, 208 enable continuous pressure-generating operation of the salt power plant. If one of the two pressure silos is filled with salt or the respective osmosis membrane unit needs to be replaced, and the upper opening 126, 226 is opened for this purpose, the second pressure silo can continue to operate without problems. This would require additional valves and gate valves connected to the outlet openings 122, 222, which are opened and closed in a sensible sequence, also depending on the inflow gate valves 112, 212.

[0085] Fig. 3 shows the osmosis membrane unit 114 in greater detail. The size of the actual osmosis membrane, which is depicted on the meandering support structure 302 of unit 114, significantly influences the efficiency of the salt power plant. The possibility of designing the support structure 302 in a meandering shape, onto which the actual osmosis membrane then flies from the direction of the pressure silo, is just one of several possibilities.

[0086] Another possibility (not shown) is to provide a comparatively large number of tubular individual osmosis membranes arranged parallel to one another. These do not necessarily have to be arranged in a funnel shape. Other orientations are also conceivable. However, even with this arrangement, the goal is to create the largest possible area of ​​one or more osmosis membrane layers between the respective prechamber 106, 206 and the interior of the respective pressure silo 108, 208.

[0087] The brackets 304 shown in the upper area of ​​the osmosis membrane unit 114 can be used on the one hand to lift the osmosis membrane unit 114 out of the pressure silo, but on the other hand can also be used for locking within the pressure silo.

[0088] Fig. 4 again shows a detailed view 400 of the lower area of ​​the pressure silo 108, the locked osmosis membrane unit 114, the pre-chamber 106 below the osmosis membrane unit 114, the inflow chamber 102 and the second inflow chamber 128, as well as the inflow valves 112, 130. This figure also shows the function of the tidal cleaner 402, which consists of a float 404 floating on the water surface 120. The tidal cleaner 402 also includes a rod 406 or similar and a scraper 408. The scraper 408 moves up and down relative to the inlet grate 410 to the extent that the float 404 moves on the rising / falling water surface 120 in the rhythm of the ebb and flow of the tide.

[0089] Fig. 5 shows a method 500 for operating a salt power plant, such as the salt power plant 100 of Fig. 1. The method comprises a series of steps that can be described as follows:

[0090] Filling, 502, the first pressure silo 108 with free-flowing salt through the first upper hermetically sealable opening 126 of the first pressure silo 108, so that the first osmosis membrane unit 114 is completely covered with the salt or brine (not shown).

[0091] Once the salt has been added and the pre-chamber 106 is filled with inflow water, and if necessary, an initial amount of water is also present in the first pressure silo 108 on the silo-side of the osmosis membrane unit, osmosis begins, with water being "sucked" into the pressure silo 108 by the osmosis effect of the different salt concentrations in the pre-chamber 106 and in the pressure silo 108. It now becomes clear why two inflow chambers 102 and 128 are useful. This is because it ensures good water exchange in the pre-chamber 106 through natural water movement, e.g., near the coast of a sea.

[0092] In order for the salt power plant to release the appropriate pressure at the upper outlet connection 122, it is also necessary to vent the first pressure silo 108, 504. This can be done using a vent valve (not shown) in the upper area of ​​the pressure silo. After venting, the first outlet connection can be opened, 506. Shortly thereafter, or even almost simultaneously, the at least first inlet valve 112 can be opened, 508, so that a continuous water flow into the first prechamber begins.

[0093] Fig. 6 shows a method 600 for operating a salt power plant, such as the salt power plant 200 with two pressure silos. The simplified method 600 provides for parallel operation 602 of the first pressure silo and the second pressure silo in a pressure-generating state. If, for example, it turns out that salt needs to be refilled in the first pressure silo or that the osmosis membrane unit needs to be replaced, the method provides for closing 604 of at least one first inlet valve (and possibly also the second inlet valve) and closing 606 of the first outlet connection. This is followed by opening 608 of the first closable opening of the first pressure silo, and subsequently filling 610 of the first pressure silo with salt through the first upper, hermetically sealable opening of the first pressure silo. Following this, the first pressure silo can return to productive operation.Subsequently, the second pressure silo can be filled with salt in a similar manner, or the osmosis membrane unit can be replaced. This allows for continuous pressure-generating operation by alternating the pressure silos. It should also be mentioned that a larger number of comparable pressure silos can also be operated with associated peripheral units, such as an associated osmosis membrane unit.

[0094] The illustrated structures, materials, processes, and equivalents of all means and / or steps with associated functions in the claims below are intended to employ all structures, materials, or processes as expressed by the claims.

[0095] It should also be mentioned that the salt solution escaping from the pressure silo's outlet connection can be used to convert pressure energy into rotational energy or other forms of energy in a salt power plant, such as a single-stroke piston machine, a double-stroke piston machine, or a turbine. It can then be transported or directed to a drying station. Here, the water can be removed from the salt solution (evaporation), particularly through direct sunlight. The resulting crystalline salt can then be returned to the pressure silo(s) in a circular process to continuously maintain osmotic pressure. In this way, virtually only natural resources are used to generate energy: on the one hand, the flowing (sea) water, and on the other, solar energy, which transforms the used salt solution into crystalline salt through evaporation.

[0096] This provides a wide range of possible applications 700, as shown in Fig. 7. The energy generated in the form of pressure in the salt power plant 100 can be converted into kinetic energy 702. This energy can be used directly for water purification 704 in an environmentally beneficial manner. This can be done using water reverse osmosis 706 (water RO). Alternatively, hydrogen 708 can be obtained from the kinetic energy (using generators) by means of electrolysis by generating electricity 710. Furthermore, it is possible to use the energy generated by the salt power plant to generate heat 712. Various possibilities are conceivable, such as combustion of the hydrogen or the conversion of electrical energy into thermal energy.

[0097] Additionally, the connection shown from the pressure silo to "water directly" should be noted. The water can be obtained using a vacuum evaporator, both with and without the interposition of the energy generation unit 702.

[0098] More practical procedures should be described for completeness; A: Starting the SKW: i. Close the inlet valve; ii. Close the pressure or outlet connection of the pressure silo; iii. Open the pressure relief outlet (= overflow, not shown); iv. Open the hermetically sealable opening on the pressure silo; v. Fill the pressure silo, including the osmosis membrane unit inside, with salt and water (e.g., also sea and / or wastewater); vi. Close the hermetically sealable opening; vii. Close the pressure relief outlet; viii. Open the outlet connection; and ix. Open the inlet valve (the system can be vented automatically). B: Refill salt: i. Close the inlet valve; ii. Close the outlet connection of the pressure silo; iii. Open the pressure relief outlet; iv. Open the airtight, sealable opening; v. Fill the pressure silo, including the osmosis membrane unit inside, with salt (brine already present); vi. Close the airtight, sealable opening; vii. Close the pressure relief outlet; viii. Open the outlet connection; and ix. Open the inlet valve (the system will vent automatically). C: Replace the osmosis membrane unit (only when the salt in the pressure silo has been used up): i. Close the inlet valve; ii. Close the outlet connection of the pressure silo; iii. Open the pressure relief outlet; iv. Open the airtight, sealable opening; v. Remove the osmosis membrane unit; vi. Insert the new osmosis membrane unit; vii. Fill the pressure silo, including the new osmosis membrane unit inside, with salt and a starting amount of water; viii. Close the airtight, sealable opening; ix. Close the pressure relief outlet; x. Open the outlet connection; and xi. Open the inlet valve (the system will vent automatically).

Claims

PATENT CLAIMS A salt power plant (100) based on a potential difference between incoming water on the one hand and a salt solution on the other hand, the salt power plant (100) comprising - a first inflow chamber (102) with a water inlet (104) - a first pre-chamber (106) located between the first inflow chamber (102) and a first pressure silo (108), wherein the first pressure silo (108) can be closed in a pressure-tight manner except for its fluid connection (110) with the first pre-chamber (106), - at least one first inlet valve (112) arranged between the first inlet chamber (102) and the first pre-chamber (106), so that the first inlet chamber (102) can be fluidly separated from the first pre-chamber (106), - a first osmosis membrane unit (114) located within the first pressure silo (108) and between the first pre-chamber (106) and an interior space (116) of the first pressure silo (108), wherein the first osmosis membrane unit (114) is removable from the interior of the first pressure silo (108) in a direction (118) opposite to a direction toward the first pre-chamber (106), - wherein the first pressure silo (108) and the first osmosis membrane unit (114) are fillable with free-flowing salt, and wherein the first osmosis membrane unit (114) is in a pressure-producing state below a water level (120) of the inflowing water and the first pressure silo (108) is filled with the salt solution, wherein the fluid connection from the water inlet (104) via the first inflow chamber (102) and the first pre-chambers (106) to the first osmosis membrane unit (114) is filterless, and - a first outlet connection (122) in an upper region of the first pressure silo (108). The salt power plant (100) according to claim 1, - wherein the first osmosis membrane unit (114) is substantially horizontal and wherein the first osmosis membrane unit (114) has a surface area that is at least 10 times larger than a cross-section (124) of a direct fluid connection between the first pre-chamber (106) and the interior of the first pressure silo (108). The salt power plant (100) according to claim 1 or 2, - wherein the first osmosis membrane unit (114) has a substantially funnel-shaped support structure (302), and - wherein a first osmosis membrane is located above the funnel-shaped support structure (302) so as to have a larger surface area than the cross-section (124) of the direct fluid connection between the first pre-chamber (106) and the interior of the first pressure silo (108). The salt power plant (100) according to one of claims 1 or 2, wherein the first osmosis membrane unit (114) comprises a support structure (302) in which a plurality of tubular individual osmosis membranes arranged parallel to one another are arranged. The salt power plant (100) according to one of the preceding claims, - wherein the interior of the first pressure silo (108) can be filled with salt through a first upper, hermetically sealable opening (126) of the first pressure silo (108). The salt power plant (100) according to one of the preceding claims, additionally comprising - a second inflow chamber, which is fluidly separable from the first prechamber by a second inflow valve. The salt power plant (100) according to one of the preceding claims, additionally comprising - a second pre-chamber located between the first inflow chamber and a second pressure silo, wherein the pressure silo can be closed pressure-tight except for its fluid connection with the second pre-chamber, - at least one second inlet valve arranged between the first inflow chamber and the second pre-chamber, so that the first inflow chamber can be fluidly separated from the second pre-chamber, - a second osmosis membrane unit located within the second pressure silo and between the second pre-chamber and an interior of the second pressure silo, wherein the second osmosis membrane unit is removable from the interior of the second pressure silo in a direction opposite to a direction towards the second pre-chamber, - wherein the second pressure silo and the second osmosis membrane unit are fillable with free-flowing salt, and wherein the second osmosis membrane unit is in a pressure-producing state below a water level of the inflowing water and the second pressure silo is filled with the salt solution, wherein the fluid connection from the water inlet via the first inflow chamber and the second pre-chamber to the second osmosis membrane unit is filterless, and - a second outlet connection in an upper region of the second pressure silo. The suction chamber, the pre-chamber, and the second osmosis unit are fluidly connectable to one another in this order. The salt power plant (100) according to one of the preceding claims, additionally comprising: - a pressure-tight, closed fluid connection between the first outlet connection and a salt power plant, which converts an overpressure in the first pressure silo into kinetic energy. The salt power plant (100) according to claim 8, wherein the salt power plant is a single-stroke piston engine, a double-stroke piston engine, or a turbine. The salt power plant (100) according to one of claims 7 to 9, additionally comprising - a first venting unit connected to the first pressure silo, and / or a second venting unit connected to the second pressure silo. The salt power plant (100) according to one of claims 9 or 10 additionally comprising - an evaporation unit that collects the brine leaving the salt power plant. The salt power plant (100) according to one of the preceding claims, wherein the first inflow chamber has a grating at the water inlet, and wherein the grating is cleanable by a tidal cleaner. The salt power plant (100) according to claim 12, wherein the tidal cleaner comprises a float and a scraper that are mechanically connected to one another such that the scraper can be guided over an outer surface of the grating according to a tide-dependent water level, thereby causing cleaning of the grating. A method for operating a salt power plant according to one of claims 1 to 13, the method comprising - Filling the first pressure silo with free-flowing salt through the first upper hermetically sealable opening of the first pressure silo so that the first osmosis membrane unit is completely covered with the salt, - Venting the first pressure silo, - Opening the first outlet port, and - Opening the at least first inlet valve, so that a continuous water flow into the first prechamber is caused. The method according to claim 14, additionally comprising - parallel operation of the first pressure silo and the second pressure silo in a pressure-generating state, - closing at least one first inlet valve, - Closing the first outlet connection, - Opening the first closable opening of the first pressure silo, and - Filling the first pressure silo with salt through the first upper hermetically sealable opening of the first pressure silo. The method according to claim 15, additionally comprising - Replacing the first osmosis membrane unit via the first upper hermetically sealable opening of the first pressure silo.

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