EP2930318A1 - Method and system for storing and recovering energy - Google Patents

Abstract

A method for storing and recovering energy is proposed in which an air liquefaction product (LAIR) is formed in an energy storage period and a pressure current is formed and released during work in an energy recovery period using at least part of the air liquefaction product (LAIR) without heat supply from an external heat source , The method comprises, inter alia, to compress air (AIR) in an air conditioning unit (10), at least by means of an adiabatically operated compressor device (12), downstream of the adiabatically operated compressor device (12) from the compressed air in said air conditioning system (10). AIR) to form a first and a second partial flow and to lead the first and the second partial flow in parallel through a first heat storage device (131) and a second heat storage device (132), where at least partially stored heat generated during the compression of the air (AIR) becomes. Among other things, at least part of the liquefaction product (LAIR) is produced from a liquefaction product (HPAIR) to form the pressure stream. The pressure flow is performed in the work-performing relaxation by a first expansion device (61) and a second expansion device (62) and in each case relaxed. Upstream of the first expansion device (61) heat stored in the first heat storage device (131) is transferred to the pressure flow and upstream of the second expansion device (62) heat stored in the second heat storage device (132) is transferred to the pressure flow. An attachment (100) is also an object of the present invention.

Description

The present invention relates to a method and a system for storing and recovering energy, in particular electrical energy, according to the preambles of the respective independent claims.

State of the art

For example, from the DE 31 39 567 A1 and the EP 1 989 400 A1 It is known to use liquid air or liquid nitrogen, ie cryogenic air liquefaction products, for grid control and for the provision of control power in power grids.

At low flow times or excess flow times, air in an air separation plant with an integrated condenser or in a dedicated liquefaction plant, generally also referred to as an air treatment unit, is liquefied in whole or in part to form such an air liquefaction product. The air liquefaction product is stored in a tank system with cryogenic tanks. This mode of operation occurs during a period of time, referred to herein as the energy storage period.

At peak load times, the air liquefaction product is withdrawn from the tank system, pressure increased by a pump and warmed to about ambient temperature or higher and thus converted to a gaseous or supercritical state. A pressure flow obtained in this way is expanded down to ambient pressure in an energy recovery unit in an expansion turbine or in several expansion turbines with intermediate heating. The thereby released mechanical power is converted into electrical energy in one or more generators of the power generation unit and fed into an electrical grid. This mode of operation occurs during a period of time, referred to herein as the energy recovery period.

The released during the transfer of the air liquefaction product in the gaseous or supercritical state during the energy recovery period

Cold can be stored and used during the energy storage period to provide refrigeration to recover the air liquefaction product.

There are also known compressed air storage power plants in which the air is not liquefied, but compressed in a compressor and stored in an underground cavern. In times of high electricity demand, the compressed air from the cavern is directed into the combustion chamber of a gas turbine. At the same time, the gas turbine is supplied via a gas line fuel, such as natural gas, and burned in the atmosphere formed by the compressed air. The formed exhaust gas is expanded in the gas turbine, thereby generating energy.

The present invention is to be distinguished from methods and apparatus in which an oxygen-rich fluid is introduced to promote oxidation reactions in a gas turbine. Corresponding methods and devices basically operate with air liquefaction products which contain (significantly) more than 40 mole percent oxygen.

The economics of such methods and devices are greatly affected by the overall efficiency. The invention is therefore based on the object to improve corresponding methods and devices in this regard.

Disclosure of the invention

Against this background, the present invention proposes a method and a system for storing and recovering energy, in particular electrical energy, with the features of the respective independent patent claims. Preferred embodiments are the subject matter of the dependent claims and the following description.

Before explaining the advantages that can be achieved within the scope of the present invention, its technical principles and some terms used in this application are explained in more detail.

A "power generation unit" is understood here to mean a plant or a plant part which is or is set up for generating electrical energy. A Energy generating unit includes in the context of the present invention, at least two expansion turbines, which are advantageously coupled to at least one electric generator. A relaxation machine coupled to at least one electrical generator is also referred to as a "generator turbine". The mechanical power released during the expansion of a fluid in an expansion turbine or generator turbine can be converted into electrical energy in the energy production unit.

An "expansion turbine", which may be coupled via a common shaft with further expansion turbines or energy converters such as oil brakes, generators or compressor stages, is set up for relaxation of a supercritical, gaseous or at least partially liquid stream. In particular, expansion turbines may be designed for use in the present invention as a turboexpander. If one or more expansion turbines designed as a turboexpander are coupled to one or more compressor stages, for example in the form of centrifugal compressor stages, and if necessary mechanically braked, but these are operated without externally supplied energy, for example by means of an electric motor, the term Booster turbine "used. Such a booster turbine compresses at least one current by the relaxation of at least one other current, but without external, for example by means of an electric motor, supplied energy.

In the context of the present application, a "gas turbine unit" is understood to mean an arrangement of at least one combustion chamber and at least one of these downstream expansion turbines (the gas turbine in the narrower sense). In the latter, hot gases are released from the combustion chamber to perform work. A gas turbine engine further includes at least one compressor stage driven by the expansion turbine via a common shaft, typically at least one axial compressor stage. Some of the mechanical energy generated in the expansion turbine is usually used to drive the at least one compressor stage. Another part is regularly converted to generate electrical energy in a generator. The expansion turbine of the gas turbine is thus a generator turbine in the sense explained above. As a modification of a gas turbine unit, a "combustion turbine unit" has only the mentioned combustion chamber and a downstream expansion turbine. A compressor is usually not provided. A "hot gas turbine unit", in contrast to a gas turbine unit instead of a combustion chamber on a heater. A hot gas turbine unit may be formed in one stage with a heater and an expansion turbine. Alternatively, it is also possible to provide a plurality of expansion turbines, preferably with intermediate heating. In any case, in particular downstream of the "last" expansion turbine, a further heater may be provided. The hot gas turbine is also preferably coupled to one or more generators for generating electrical energy.

Since, in the context of the present invention, no heat originating from external sources is used in the formation of a pressure flow in an energy recovery period, no gas or combustion turbine units are used here, but at most hot gas turbine units which are heated via suitable heat accumulators.

A "compressor device" is here understood to mean a device which is set up for compressing at least one gaseous stream from at least one inlet pressure at which it is fed to the compressor device to at least one final pressure at which it is taken from the compressor device. The compressor device thereby forms a structural unit, which, however, can have a plurality of individual "compressors" or "compressor stages" in the form of known piston, screw and / or paddle wheel or turbine arrangements (ie radial or axial compressor stages). In particular, these compressor stages are driven by means of a common drive, for example via a common shaft or a common electric motor. Several compressors, e.g. Compressors in an air conditioning unit used according to the invention can together form one or more compressor devices.

In the language used here, an "air conditioning unit" comprises at least one adiabatically operated compressor device and at least one adsorptive air purification device. Adsorptive air cleaners are well known in the art of air separation. In adsorptive Air purification devices are guided one or more air streams through one or more adsorber, which are filled with a suitable adsorption material, such as molecular sieve.

The present invention comprises at least the liquefaction of air to an air liquefaction product. The devices used for this purpose can also be summarized under the term "air treatment unit". This is understood in the parlance of the present application, a system which is adapted to recover at least one air liquefaction product from air. Sufficient for an air treatment unit for use in the present invention is that it can be obtained by this a corresponding cryogenic air liquefaction product, which can be used as a storage liquid and transferred to a tank system. An "air separation plant" is charged with atmospheric air and has a distillation column system for decomposing the atmospheric air into its physical components, particularly nitrogen and oxygen. For this purpose, the air is first cooled to near its dew point and then introduced into the distillation column system. In contrast, an "air liquefaction plant" does not include a distillation column system. Incidentally, their structure corresponds to that of an air separation plant with the delivery of an air liquefaction product. Of course, liquid air can be generated as a by-product in an air separation plant.

An "air liquefaction product" is any product that can be produced, at least by compressing, cooling, and then deflating air in the form of a cryogenic liquid. In particular, an air liquefaction product may be liquid air, liquid oxygen, liquid nitrogen and / or a liquid noble gas such as liquid argon. The terms "liquid oxygen" and "liquid nitrogen" in each case also designate a cryogenic liquid which has oxygen or nitrogen in an amount which is above that of atmospheric air. It does not necessarily have to be pure liquids with high contents of oxygen or nitrogen. Under liquid nitrogen is thus understood as pure or substantially pure nitrogen, as well as a mixture of liquefied air gases, its nitrogen content higher than that of the atmospheric air. For example, it has a nitrogen content of at least 90, preferably at least 99 mole percent.

If we are talking about a "defrosting product", this is understood as meaning a fluid formed by transferring a liquid in the gaseous or supercritical state. If a liquid is "evaporated" at supercritical pressure, it does not pass into the gas phase but into the supercritical state, with no phase transition taking place in the true sense. This is also referred to as "pseudoevaporating". At subcritical pressure, there is a phase transition from the liquid to the gaseous state, ie a conventional "evaporation". In the context of the present application, a liquefaction therefore comprises both evaporation and pseudo-vaporization. After liquefaction, whether from the gaseous or supercritical state, there is always a liquid. Both cases are therefore covered by the term "liquefaction".

Under a "cryogenic" liquid, or a corresponding fluid, air liquefaction product, electricity, etc., a liquid medium is understood, the boiling point is well below the respective ambient temperature and, for example, 200 K or less, in particular 220 K or less. Examples are liquid air, liquid oxygen, liquid nitrogen, etc.

In the context of this application, a "fixed bed cold storage unit" is understood to mean a device which contains a solid material suitable for cold storage and has fluid guidance means through this material. Known fixed-bed cold storage units, which are also referred to as regenerators in conventional air separation plants and are also used there for the separation of undesirable components such as water and / or carbon dioxide include, for example channeled concrete blocks (unusual in air separation plants), (stone) beds and / or fluted aluminum sheets and are flowed through by the respective streams to be cooled or heated in opposite directions and successively. In the context of this application, the term "cold storage" or "(fixed bed) cold storage unit" as opposed to "heat storage" or "heat storage unit" is used to express the difference in the operating temperature. The fixed-bed cold storage unit is condensed in the context of the present invention for liquefaction and adsorptively purified air is used for an air liquefaction product and for its liquefaction, so it is operated at least in one area at cryogenic temperatures. In contrast, the heat storage devices used in the present invention are always operated at significantly higher temperatures and serve to store in the adiabatic compression of the air generated (compression) heat.

A refrigeration or heat storage unit comprises one or more refrigeration or heat storage with appropriate refrigeration and heat storage media. The refrigeration or heat storage media that can be used in one or more refrigeration or heat stores depend on the configuration of the method.

Heat storage and (fixed bed) cold storage are extensively described in the relevant literature (see, for example i. Dinçer and MA Rosen, "Thermal Energy Storage Systems and Applications", Chichester, John Wiley & Sons 2002 ). Suitable storage media are, for example, rock, concrete, brick, man-made ceramics or cast iron. For lower storage temperatures are also suitable earth, gravel, sand or gravel. Other storage media such as thermal oils or molten salts are known, for example, in the field of solar technology. In corresponding cold stores, it may prove to be particularly advantageous to provide the storage medium in an insulated container, which allows a lossless or almost lossless heat or cold storage.

A "countercurrent heat exchange unit" is formed using one or more countercurrent heat exchangers, for example, one or more plate heat exchangers. In contrast to a fixed-bed cold storage unit, the cooling in a countercurrent heat exchange unit is not effected by delivery to or absorption of heat from a fixed bed, but indirectly to or from a countercurrent heat or cold carrier. As a heat exchanger in a countercurrent heat exchange unit for use in the present invention, all known heat exchangers, such as plate heat exchangers, tube bundle heat exchangers and the like are suitable. A countercurrent heat exchange unit serves for the indirect transfer of heat between at least two countercurrent flows, for example a warm compressed air flow and one or more cold streams or a cryogenic air liquefaction product and one or more warm streams. A countercurrent heat exchange unit may be formed from a single or multiple parallel and / or serially connected heat exchanger sections, eg, one or more plate heat exchanger blocks. Is here below a "heat exchanger" the speech, this can be understood as a countercurrent heat exchanger or another heat exchanger.

A heat storage unit used in the context of the present invention may also comprise a countercurrent heat exchanger through which, for example, a suitable heat storage fluid, such as the mentioned thermal oil, flows through in countercurrent to a stream to be heated or cooled. The heat storage fluid, which forms the heat storage medium here, can be provided for example in a double or multiple tank arrangement, as also explained in more detail below.

In the context of this application, a "heater" is understood to mean a system for indirect heat exchange between a heating fluid and a gaseous fluid to be heated. By means of such a heater, residual heat, waste heat, process heat, solar heat, etc. can be transferred to the gaseous fluid to be heated and used for energy generation in a hot gas turbine.

Methods and devices for the cryogenic separation of air and the methods and devices which can be used there and also within the scope of the present invention are also described, for example, in US Pat Haring, H.-W. (Ed.), "Industrial Gases Processing", Weinheim, Wiley-VCH 2008 (especially Chapter 2.2.5, "Cryogenic Rectification ") and Kerry, FG, "Industrial Gas Handbook - Gas Separation and Purification", Boca Raton, CRC Press 2006 (especially Chapter 3, "Air Separation Technology ").

The present application uses the terms "pressure level" and "temperature level" to characterize pressures and temperatures, which is to express that pressures and temperatures in a given equipment need not be used in the form of exact pressure or temperature values to achieve this to realize innovative concept. However, they are moving such pressures and temperatures typically in certain ranges, for example, ± 1%, 5%, 10%, 20%, or even 50% about an average. Corresponding pressure levels and temperature levels can be in disjoint areas or in areas that overlap one another. In particular, for example, pressure levels include unavoidable pressure drops or expected pressure drops, for example, due to cooling effects or line losses. The same applies to temperature levels. The pressure levels specified here in bara are absolute pressures in bar.

Advantages of the invention

The invention proposes a method for storing and recovering energy, wherein formed in an energy storage period, a Luftverflüssigungsprodukt and formed in an energy recovery period using at least a portion of the Luftverflüssigungsprodukts without heat from an external heat source, a pressure stream and work expanded.

According to the invention, therefore, no additional heat is introduced into the process or a corresponding system for forming the pressure flow, so for example there is no electrical heating or firing. The heating is performed solely using heat generated in the process itself, as explained in detail below.

As already mentioned, in the context of this application an air liquefaction product is understood to mean any product which can be produced by compression and cryogenic cooling of air in the liquid state. The present invention will be described below with particular reference to liquid air as an air liquefaction product, but it is also suitable for other air liquefaction products, especially oxygen-containing air liquefaction products. In contrast to the methods and devices mentioned in the introduction, in which an oxygen-rich fluid is introduced into a gas turbine to assist oxidation reactions, an oxygen-containing air liquefaction product with (clearly) less than 40, 35 or 30 mole percent oxygen, for example the oxygen content, is advantageously used here natural air. A distillative separation of an air liquefaction product is therefore not required.

The terms "energy storage period" and "energy recovery period" have already been mentioned. These are understood in particular as periods that do not overlap one another. This means that the measures described below for the energy storage period are typically not carried out during the energy recovery period and vice versa. However, it can also be provided, for example, to carry out at least part of the measures described for the energy storage period at the same time as the measures described for the energy recovery period, for example in order to ensure greater continuity in the operation of a corresponding system. For example, in an energy storage period of an energy recovery unit, a pressure flow can be supplied and expanded in this work, for example, to be able to operate without relaxation, the relaxation facilities used here. The energy storage period and the energy recovery period each correspond to an operating or process mode of a corresponding system or a corresponding method.

In order to form the air liquefaction product, the present invention comprises compressing air in an air conditioning unit at least by means of an adiabatically operated compressor device and adsorptively purifying it by means of at least one adsorptive purification device at a superatmospheric pressure level. Details on adiabatic compression are explained below. In particular, heat may be provided by the adiabatic compression to heat the pressure flow in the energy recovery period.

As also explained in detail below, in the air conditioning unit downstream of the adiabatically operated compressor device, a first and a second partial flow are formed from the compressed air in this. The partial flows are conducted in parallel through a first heat storage device and a second heat storage device. In this way, heat generated in the compression of the air is at least partly stored in the first heat storage device and the second heat storage device and is available for subsequent heating.

The compressed and adsorptively purified air is downstream of the air conditioning unit and optionally after a further (for example isothermal) compression in this, starting from a temperature level in a range of 0 to 50 ° C to a first portion in a fixed bed cold storage unit and a second portion in a countercurrent heat exchange unit at a condensing pressure level in a range of 40 to 100 bara liquefied. The liquefied air is subsequently expanded in at least one refrigeration unit.

In the context of the present invention, in order to form the pressure stream from at least part of the liquefaction product, a liquefaction product is produced in the fixed bed cold storage unit at a defrosting pressure level which does not deviate from the condensing pressure level by more than 5 bar. The de-condensation product can be used directly or after further pressure and / or temperature-influencing measures as the pressure flow. The Entflüssigungsprodukt can be divided to form the pressure flow, for example, in two or more streams, one of which is used as a pressure stream and / or the Entflüssigungsprodukt can this be combined with one or more further streams.

It is further provided to guide the pressure flow in the work-performing expansion by a first expansion device and a second expansion device and thereby to relax the pressure flow, and to transfer heat stored upstream of the first expansion device in the first heat storage device to the pressure flow and upstream of the second expansion device in the second heat storage device to transfer stored heat to the pressure flow.

In addition to the explicitly mentioned first and second relaxation device can also be provided more relaxation facilities, the relaxation can thus be at least two stages, but also, for example, three and more stages. Particular advantages, however, arise when only exactly two expansion devices are used for work-performing expansion of the pressure flow and only exactly two compressor devices in the air conditioning. This makes it possible to realize a corresponding system much easier and cheaper than the technically possible use of three or more expansion devices for work-performing expansion of the pressure flow and three or more compressor devices in the air conditioning.

The two-stage or multi-stage expansion of the pressure stream in the energy recovery period is advantageous because the pressure stream to be relaxed is at a high pressure level of typically more than 40 bara, and especially in the supercritical state. It would therefore be technically very complicated to realize the relaxation of this high pressure level to about ambient pressure in a single machine. In addition, the pressure flow during the relaxation is cooled in proportion to the pressure difference achieved during the relaxation. Negative temperatures at the exit from the or each relaxation devices used, however, should be avoided. This problem can be solved according to the invention by heating upstream of the respective expansion devices.

In the air conditioning unit used in the invention, two or more compressor units are typically used. In principle, it would be advantageous to use successively two adiabatically operated compressor devices, ie compressor devices, in which the compressed air has a significantly higher temperature than the air to be compressed. The amount of heat generated in each case could then be stored in each case in a heat storage device and, on the other hand, be transferred to the pressure flow upstream of the first expansion device on the one hand and upstream of the second expansion device on the other hand.

However, this generation of "two amounts of heat" encounters technical difficulties because adiabatically operable compressor devices are typically not available for the total pressure to be generated in the air conditioning unit used in the present invention, but only for generating pressure levels less than 20 bara from atmospheric pressure. These are typically components that are also used in compression stages of gas turbines. For higher pressure levels, for example for the compression of 10 to 20 bara to 40 to 60 bara, no adiabatically operable compressor are available. Compressors for correspondingly high pressures are set up for (quasi-) isothermal operation, so that sufficient heat can not be obtained here.

The method according to the invention therefore comprises forming a first partial flow and a second partial flow in the air conditioning unit downstream of an adiabatically operated compressor device from the compressed air in this compressor device and to lead the first and the second partial flow parallel through the first heat storage device and the second heat storage device. The "parallel" guiding of the partial flows need not necessarily comprise a division of the compressed air into partial flows with the same volume flow. Rather, it is also possible to divide the air "asymmetrically", for example, to store a larger amount of heat in one of the heat storage devices and to provide for heating the pressure flow. The division can also be made on the basis of a suitable control, for example on the basis of an already stored in the respective heat storage devices amount of heat. In any event, the use of the first and second heat storage devices provides two separate heat sources available for heating the pressure flow in the energy recovery period upstream of the two expansion devices.

In addition to the division of the compressed air and the parallel guiding by the heat storage devices, it is also possible in principle to store heat in the first heat storage device in a first sub-period of the energy storage period and heat in the second heat storage device in a second sub-period.

The addressed adiabatic compressor device is advantageously one of at least two compressor devices in the air conditioning unit, which is operated at a correspondingly low pressure level, for example 20 bara or less, or compresses the air from atmospheric pressure to a correspondingly low pressure level. For example, this compressor device is the first in a series of serially arranged compressor devices.

An essential aspect of the present invention is therefore also the use of an adiabatically operated, "heat-generating" compressor device. One or more further compressor devices, in particular compressor devices for higher pressure levels, however, can be operated isothermally. Overall, it can be reduced by the present invention, the number of hardware components, resulting in lower cost and maintenance and easier operation of the entire system.

In the present invention, as mentioned, it is contemplated to operate the fixed bed cold storage in the energy storage mode and the energy recovery mode at equal or similar pressure levels (the condensing pressure level and the defrosting pressure level) in the range of 40 to 100 bara. As a result, pressure fluctuations are avoided within the fixed bed storage and increases its mechanical stability, or significantly reduced requirements for its mechanical strength. In this case, the air in the at least one air conditioning unit is compressed to a corresponding pressure level, which may be at subcritical or supercritical pressure to form the air liquefaction product. In the fixed-bed cold storage unit and the countercurrent heat exchange unit can thus be converted into a corresponding high-pressure air stream from the supercritical state (without classical phase transition) or the subcritical state in the liquid state. Both transitions are summarized here by the term "liquefying". The same applies to the already explained formation of the degassing product by "liquefaction".

In the context of the present invention, as mentioned above, it is further provided to supply the first portion and the second portion of the compressed and adsorptively purified air to the fixed bed cold storage unit and the countercurrent heat exchanger unit at a temperature level of 0 to 50 ° C. The Ei nspeisung is thus advantageously at ambient temperature, which allows a particularly advantageous operation of the fixed bed cold storage unit.

This can be made possible, in particular, by the fact that a further, isothermally operated compressor device is used in the air conditioning unit downstream of the adiabatically operated compressor device. An isothermally operated compressor device, which may have one or more compressor stages or compressors in the sense explained above, is characterized in that one of these supplied and one of these removed, compressed stream in the Substantially have a same temperature level, in contrast to adiabatically operated compressors, in which the compression product has a significantly higher temperature than the current fed into the compressor device. An isothermally operated compressor device has, for example, intermediate and aftercooler.

Because in the context of the present invention, the liquefied in the energy storage period in the fixed bed cold storage unit and the countercurrent heat exchange unit air is relaxed in a refrigeration unit, the provision of additional cold is possible, for example, compensates for cold losses in a corresponding system, for example in a storage tank for receiving the air liquefaction product. An evaporation product formed during the expansion can also be used as a regeneration gas, as explained below.

In the context of the method according to the invention, therefore, at least one isothermally operated compressor device is advantageously also used in the air conditioning unit in addition to the at least one mentioned adiabatically operated compressor device.

In the context of the method according to the invention, as also mentioned, an air conditioning unit is used with at least one adsorptive cleaning device operated at a superatmospheric pressure level. As mentioned, the air conditioning unit used in the present invention compresses the supplied air over several pressure stages. The adsorptive cleaning device can be used or provided on each of these pressure stages. For example, a cleaning device at a final pressure level, which is provided by the air conditioning unit, are designed to be particularly compact because low air masses have to be cleaned due to the compression. In the context of the present invention, an adsorptive cleaning device may comprise one or more adsorptive cleaning containers, as explained in more detail in the description of the figures.

In a particularly advantageous embodiment of the method according to the invention, a fixed bed and / or a liquid heat storage medium is used in at least one of the heat storage devices. Usable here Thermal storage media have been previously discussed. The use of a fixed-bed heat storage medium has the advantage of a particularly simple and cost-effective implementation; However, liquid heat storage media may have better heat capacity. The invention may also include a combination of a fixed bed and a liquid heat storage medium in one or both of the heat storage devices. For example, if a corresponding air flow is divided "asymmetrically" between the heat storage devices as discussed above, one fixed bed and one liquid heat storage medium may be employed in one of the heat storage devices. Any combinations are possible.

According to an advantageous embodiment of the method according to the invention, in at least one of the heat storage devices, a heat storage fluid can be transferred between at least two storage tanks and the heat in at least one counterflow heat exchanger can be transferred from or to the at least one heat storage fluid. In this way, the available heat can be transferred not only to a statically available heat storage medium, the absorption capacity is naturally limited, but to a larger amount of a corresponding heat medium. The absorption capacity for the available heat can thus be increased significantly.

As already mentioned, the heat storage devices in the context of the present invention are operated at significantly higher temperatures than the fixed bed cold storage device. In particular, the respective heat storage medium in at least one of the heat storage devices during the energy storage period is heated to a temperature level of 50 to 400 ° C.

In the method according to the invention, a generator turbine is advantageously used as the first expansion device and as the second expansion device. As mentioned above, a generator turbine is understood to mean any expansion machine coupled to a generator. The use of a generator turbine allows flexible recovery of energy in the form of electrical power. In principle, however, the invention for recovering the energy may also include the use of other measures, for example the Operation of a means of a relaxation machine or a pump connected thereto hydraulic accumulator.

The method according to the invention may also include heating, relaxing and / or compressing the fluid flow at least one (further) time before the work-performing expansion in the first and the second expansion device. For example, at least a portion of the degassing product may also initially be passed through a heat exchanger and already heated therein.

Advantageously, the at least one adsorptive cleaning device is supplied with a regeneration gas in a regeneration phase which is formed from part of the air previously compressed and adsorptively cleaned in the air conditioning unit. A corresponding regeneration gas is advantageously heated prior to its use, as also explained below. A regeneration phase of an adsorptive cleaning device can, if only one cleaning container is present, be carried out when no cleaning power has to be provided by the cleaning device, for example in an energy recovery period. If several cleaning containers which can be operated in alternation are present, they can be regenerated independently of the respective period of time.

The regeneration gas may be formed either from at least part of an evaporation product formed during the expansion of the liquefied air during the energy storage period or from at least part of the defrosting product during the energy recovery period.

Advantageously, an evaporation product formed during the expansion of the liquefied air is passed through the countercurrent heat exchange unit and thereby heated. The vaporization product serves to cool the second portion of the air which is compressed and adsorptively cleaned in the air conditioning unit by the countercurrent heat exchange unit. Corresponding cold can thus be used advantageously.

Advantageously, in the context of the inventive method, at least one refrigerant is passed through the countercurrent heat exchange unit, which by means of a provided external cooling circuit and / or by relaxing from a part of previously compressed in the air conditioning unit and adsorptively purified air is formed. In the latter case, for example, by means of the air conditioning unit, a larger amount of air can be compressed and adsorptively cleaned than it is needed to form the air liquefaction product and its storage. The corresponding "excess" air may optionally be cooled to an intermediate temperature in the countercurrent heat exchange unit, and then decompressed and passed through the countercurrent heat exchange unit from the cold end to the warm end. In this way, the required refrigeration demand can be covered without additional facilities. The use of an external refrigeration cycle, however, allows a completely independent provision of cold.

A plant adapted to store and recover energy by forming an air liquefaction product in an energy storage period and generating and extracting a pressure stream formed by using at least a portion of the air liquefaction product without heat input from an external heat source in an energy recovery period is also an object of the present invention ,

The system has means which are set up to compress air in an air conditioning unit at least by means of an adiabatically operated compressor device and to adsorptively purify it by means of at least one adsorptive cleaning device at a superatmospheric pressure level in the air conditioning unit downstream of the adiabatically operated compressor device in the compressed air to form a first and a second partial flow and to lead the first and the second partial flow in parallel through a first heat storage device and a second heat storage device, generated in the compression of the air at least partially in the first heat storage device and the second heat storage device to store, the compressed and adsorptively purified air, starting from a temperature level in a range of 0 to 50 ° C to a first part to a fixed bed cold storage unit and a second portion in a countercurrent heat exchange unit at a condensing pressure level in one Liquefied region of 40 to 100 bara, and then to liquefy the air in at least one refrigeration unit to relax.

The means are further adapted to generate a liquefaction product in the fixed bed cold storage unit for forming the pressure flow from at least a portion of the liquefaction product at a defrost pressure level that does not deviate more than 5 bar from the condensing pressure level, and the pressure flow during work expansion by a to guide first expansion device and a second expansion device and to relax the pressure flow in each case, and to transfer heat stored upstream of the first expansion device in the first heat storage device to the pressure flow and to transfer heat stored upstream of the second expansion device in the second heat storage device to the pressure flow.

Such a system advantageously has all the means that enable it to carry out the method explained in detail above. Such a system therefore benefits from the advantages of a corresponding method, to which express reference is therefore made.

The invention will be explained in more detail with reference to the accompanying drawings, which show preferred embodiments of the invention.

Brief description of the drawings

• Figures 1A and 1B show a plant according to an embodiment of the invention in an energy storage period and an energy recovery period.
• FIG. 2 shows a system according to an embodiment of the invention in the energy storage period.
• FIGS. 3A and 3B show a plant according to an embodiment of the invention in the energy storage period and the energy recovery period.
• FIG. 4 shows a heat storage device for a system according to an embodiment of the invention.
• FIG. 5 shows a heat storage device for a system according to an embodiment of the invention.
• Figures 6A and 6B show a heat storage device for a plant according to an embodiment of the invention in the energy storage period and the energy recovery period.
• FIGS. 7A and 7B show cooling devices for air conditioning units according to embodiments of the invention.
• FIG. 8 shows an air cleaning device for an air conditioning unit according to an embodiment of the invention.
• FIG. 9 shows a compressor device with a Regeneriergasvorheizeinrichtung for an air conditioning unit according to an embodiment of the invention.
• Figures 10A and 10B show an air purification device in the energy storage period and the energy recovery period for an air conditioning unit according to specific embodiments of the invention.
• FIGS. 11A to 11C show plants according to embodiments of the invention and illustrate details of an associated countercurrent heat exchange unit.

Embodiments of the invention

In the figures, fundamentally corresponding elements, apparatus, devices and fluid streams are illustrated with identical reference numerals and will not be explained again in all cases for the sake of clarity.

In the figures, a plurality of valves is shown, which are partially permeable and partially disabled. Locking valves are shown crossed in the figures. Fluid flows interrupted by valves with shut-off valves and correspondingly deactivated devices are mainly illustrated by dashed lines. Gaseous or supercritical streams are illustrated with white (open) triangles, and flows with black (solid) arrow triangles.

In the Figures 1A and 1B is a plant according to a particularly preferred embodiment of the invention in an energy storage period ( Figure 1A ) and an energy recovery period ( FIG. 1 B) represented and designated 100 in total.

The plant 100 comprises as central components an air conditioning unit 10, a fixed bed cold storage unit 20, a countercurrent heat exchange unit 30, a refrigeration unit 40, a liquid storage unit 50 and a power generation unit 60.

Here and below, some or all of the components shown may be present in any number and, for example, be charged in parallel with corresponding partial flows.

In the in Figure 1A illustrated energy storage period, the system 100, an air flow a (AIR, feed air) is supplied and compressed in the air conditioning unit 10 and purified. A correspondingly compressed and purified, in particular freed of water and carbon dioxide, stream b is present at a pressure level of for example 40 to 100 bara and is hereinafter also referred to as high-pressure air stream b.

The stream a is sucked and compressed in the air conditioning unit 10 via a filter 11 by means of a compressor device 12, for example by means of a multi-stage, adiabatically operated axial compressor. The compressed air is divided downstream of the compressor device 12 in the illustrated example into two partial streams, each of which a heat storage device 131, 132 of a heat storage unit 13 is supplied. The multiply-described heat storage devices 131, 132 can be operated, for example, using a fixed bed and / or a liquid heat storage medium, as well as for example in the following FIGS. 4, 5 . 6A and 6B illustrated. In the Heat storage unit 13 and its heat storage devices 131, 132, the heat of compression or compressor waste heat generated in the compressor device 12 may be at least partially stored.

Downstream of the heat storage unit 13, the compressed and guided through the heat storage unit 13 stream a of a cooling device 14 and then an air cleaner 15 is supplied. Examples of corresponding cooling devices 14 and air cleaning devices 15 are inter alia in the following FIGS. 7A, 7B and 8th illustrated in more detail. For operation or regeneration of the air purification device 15, it can be supplied with a regeneration gas flow k explained below, and a current I can be carried out therefrom.

Downstream of the air cleaning device 15, a partial stream of the air of the stream a is taken as stream j, which is present at an (intermediate) pressure level of, for example, 5 to 20 bara. This current j is also referred to below as the medium-pressure air flow (MPAIR). Air of the flow a not carried out as medium-pressure air flow j is further compressed in a further compressor device 16, for example an isothermally operated compressor device 16. The compressor device 16 may be formed as a multi-stage axial compressor. Downstream of the compressor device 16, a post-cooling device 17 may be arranged. Air compressed in the compressor device 16 and cooled in the aftercooler 17 is provided as the mentioned high pressure air flow b.

As already mentioned, the high-pressure air flow b and the medium-pressure air flow j are typically provided by the air conditioning unit 10 only in the energy storage period. In this energy storage period, the energy harvesting unit 60 is typically out of operation. Conversely, in the energy recovery period, typically only the energy harvesting unit 60, rather than the air conditioning unit 10, is in operation.

The high pressure air flow b is in the in Figure 1A illustrated energy storage period of the system 100 divided into a first partial flow c and a second partial flow d. It is understood that in corresponding systems, the division of a corresponding high pressure air flow b can be provided in more than two partial streams.

The air of the partial streams c and d (HPAIR) is supplied to the fixed bed cold storage unit 20 on the one hand and the countercurrent heat exchange unit 30 on the other hand at the already mentioned pressure level of the high pressure air stream b and liquefied respectively in the fixed bed cold storage unit 20 and the countercurrent heat exchange unit 30. The air of the corresponding liquefied streams e and f (HPLAIR) is combined into a collecting stream g. The pressure level of the streams e, f and g is substantially equal, i. except for line and cooling losses, the pressure level of the high pressure air flow b.

The liquefied air of the stream g, ie an air liquefaction product, is expanded in the refrigeration unit 40, which may comprise, for example, a generator turbine 41. The expanded air can be transferred, for example, into a separator tank 42, in the lower part of which a liquid phase separates and in the upper part of which there is a gas phase.

The liquid phase from the separator tank 42 may be withdrawn as stream h (LAIR) and transferred to the liquid storage unit 50, which may include, for example, one or more insulated storage tanks. The pressure level of the current h is, for example, 1 to 16 bara. The gas phase (flash) withdrawn from the upper part of the separator tank 42 as stream i can be passed countercurrent to the stream f through the countercurrent heat exchange unit 30 and subsequently used in the air conditioning unit 10 in the form of the already mentioned stream k (LPAIR, reggas) as regeneration gas , The pressure level of the flow k is, for example, at atmospheric pressure to about 2 bara. Downstream, a corresponding current I is typically present at atmospheric pressure (amb) and can be released into the environment, for example.

While in the Figure 1A illustrated energy stored in the fixed bed cold storage unit 20 cold air for liquefying the air of the partial flow c is used. In addition, the countercurrent heat exchange unit 30 is provided in which additional air, namely air of the substream d, can be liquefied in countercurrent to, for example, a cold stream i that can be obtained from relaxed and thereby vaporized air of the stream g. The use of countercurrent heat exchange unit 30 allows more flexible operation of the plant 100 than would be the case using only the fixed bed cold storage unit 20. The countercurrent heat exchange unit 30 further provides the already mentioned medium-pressure air flow j (MPAIR).

In the in FIG. 1B illustrated energy recovery period is the liquid storage unit 50 previously stored in the energy storage period, liquefied air (LAIR), ie the air liquefaction product, taken and pressure-increased by a pump 51. A stream m (HPLAIR) thus obtained is passed through the fixed bed cold storage unit 20 and thereby vaporized or transferred from the liquid to the supercritical state ("de-liquidified"). Thus, a defrosting product is formed from which, as shown here completely, or only partially, a fluid flow is formed. The current m is at a comparable pressure level as the previously described high pressure air flow b. Also in the obtained by the evaporation or the transfer of the liquid to the supercritical state in the fixed bed cold storage unit 20, the pressure flow n is thus a high pressure air flow.

The pressure flow n is in the in FIG. 1B illustrated energy recovery period in the energy recovery unit 60 first means of in the first heat storage device 131 of the heat storage unit 13 in the energy storage period (see. Figure 1A ) stored heat and then in a first expansion device 61, which is designed here as a generator turbine, relaxed. Subsequently, the pressure flow n in the energy recovery unit 60 by means of in the second heat storage device 132 of the heat storage unit 13 in the energy storage period (see. Figure 1A ) stored heat and then in a second expansion device 62, which is also designed here as a generator turbine, further relaxed. A correspondingly relaxed current o is present, for example, at atmospheric pressure (amb) and can be released into the environment.

In the in the Figures 1A and 1B The apparatus 100 shown, the cooling device 14 and the air cleaning device 15 upstream of the compressor device 16 and downstream of the heat storage device 13 are arranged. However, it is also possible to arrange the cooling device 14 and the air cleaning device 15 downstream of the compressor device 16 and the aftercooling device 17, as shown in FIG figure 2 is shown. FIG. 2 illustrates a corresponding plant in the energy storage period, which is not designated separately. The cooling device 14 and the air cleaning device 15 are therefore provided here in a region of higher pressure and can thus be made smaller. In the in FIG. 2 Furthermore, no medium-pressure air flow j is formed.

In the in the Figures 1A . 1B and 2 A regeneration gas flow k is provided in the energy storage period in which the air purification device 15 has to perform a cleaning performance at the same time. Therefore, in appropriate systems, the air purification devices 15 must be formed inevitably operable with alternating adsorber, as well as in the FIG. 8 illustrated. On the other hand, provision of a regeneration gas flow k during the energy recovery period, in which the air purification device 15 is not required in any case, makes it possible to use only one adsorber vessel (cf. Figures 10A and 10B ) And a corresponding system so easier and cheaper to train and operate.

As can be seen from the synopsis of FIGS. 3A and 3B Therefore, in a corresponding system, the regeneration gas flow k can also be used in the energy recovery period (FIG. FIG. 3B ) are formed. For this purpose, it is preferably provided as a high-pressure stream k by being branched off from the high-pressure stream n. After its use in the air purification device 15, the regeneration gas flow k can be combined again as stream I with the high-pressure air stream n. In the stream I downstream of the air cleaner 15 contained components such as water and carbon dioxide prove due to the present in the energy recovery unit 60 temperatures usually not a problem. The in the FIGS. 3A and 3B illustrated variant has the advantage that less compressed air is lost.

In FIG. 4 a heat storage device for a system according to an embodiment of the invention is shown. As in the previous figures, the heat storage device is denoted here by 131 and 132, respectively. The in the FIG. 4 shown heat storage device 131, 132 is formed as a fixed bed heat storage device 131, 132 and has a heat storage medium in the form of a fixed bed 1. The fixed bed 1 is in a pressure vessel 2 with inlet and outlet 3 arranged and can be flowed through in this way by means of the compressor device 12 compressed air. The pressure vessel 2 is surrounded by a thermal insulating layer 4.

Also in FIG. 5 a heat storage device for a system according to an embodiment of the invention is illustrated and indicated generally at 131 and 132, respectively. A fixed-bed heat storage medium can be arranged here in a container 5 which is illustrated only schematically, through which a heat transfer fluid 6, which can be conveyed by means of a pump 7, flows. The heat transfer from the air compressed by means of the compressor device 12 of the stream a to the heat transfer fluid 6 can be effected by means of a suitable heat exchanger 8.

Unlike the in FIG. 4 shown heat storage device 131, 132 comprises in the FIG. 5 shown heat storage device 131, 132 thus an indirect heat transfer to the (not shown) heat storage medium.

In the Figures 6a and 6b is a heat storage device 131, 132, which is designed as a liquid heat storage device, in an energy storage period ( FIG. 6A ) and an energy recovery period ( FIG. 6B ).

In the in FIG. 6A illustrated energy accumulated a (after a first compression in the compressor device 12) thereby guided by a heat exchanger 71 in countercurrent to a cold heat storage fluid from a storage tank 72. The heat storage fluid from the storage tank 72 is thereby conveyed by means of a pump 73 through the heat exchanger 71 and, appropriately heated, transferred in a further storage tank 74.

In the in FIG. 6B illustrated energy recovery period, however, a current to be heated, here the high pressure air flow n, out in the opposite direction to the flow a through the heat exchanger 71 and heated by means of a now also promoted in the opposite direction, warm heat storage medium.

In FIG. 7A is a cooling device 14 for use in an air conditioning unit 10, as shown for example in the previously shown characters 1A . 1B . 2 . 3A and 3B is illustrated in detail. The cooling device 14 may be connected to a downstream of the heat storage unit 13 (see. Figures 1A . 1B and 2 ) or downstream of the Nachkühleinrichtung 17 (see. FIGS. 3A and 3B ) can be arranged. A corresponding current, designated here by r, is fed into a lower region of a direct contact cooler 141. The current r corresponds to the previously compressed in the compressor device 12 and the heat storage unit 13 cooled stream a. In an upper region of the direct contact cooler 141, a water flow (H 2 O), which is guided by means of a pump 142 through an (optional) cooling device 143, is introduced. Water can be withdrawn from a lower portion of the direct contact cooler 141. From the head of the direct contact cooler 141, a correspondingly cooled stream s is withdrawn, which is then in an air cleaning device 15 (see. Figures 1A . 1B . 2 . 3A and 3B ) can be transferred.

Deviating from the in FIG. 7B illustrated variant of the cooling device 14 no direct contact cooler 141 but a heat exchanger 144 is provided. This heat exchanger 144 can also be operated with a water flow, which is conducted by means of a pump 142 through an (optional) cooling device 143.

In FIG. 8 is an air cleaning device 15, which is particularly suitable for use in an air conditioning unit 10, as shown in the Figures 1A . 1B and 2 shown is suitable, illustrated in detail. A cooled stream s originated there, for example, from a cooling device 14, can be guided in alternating operation through two adsorber containers 151, which have, for example, molecular sieves. The current s corresponds to the current a treated as explained above. In particular, water and carbon dioxide are removed from the stream s in the adsorber containers 151. A corresponding received current t, for example, in the case of in the FIG. 2 illustrated embodiments may correspond to the current b, the downstream of each arranged device, for example, the next compressor device (see. Figures 1A and 1B ) or the fixed bed cold storage unit 20 or the countercurrent heat exchange unit 30 (see. FIG. 3 ).

The adsorber tank 151 not used in each case for purifying the stream s can be regenerated by means of the already explained regeneration gas stream k. The Regeneriergasstrom k can initially an optional Regeneriergasvorheizeinrichtung 152 are supplied, which in an example in the following FIG. 9 is illustrated. In a downstream Regeneriergasheizeinrichtung 153, which can be operated, for example electrically and / or with superheated steam, the Regeneriergasstrom k is further heated and passed through the respective adsorber tank 151 to be regenerated. Downstream of the adsorber tank 151 to be regenerated, a corresponding current I is present. The same applies if at the time shown no regeneration gas is needed, because in this case a corresponding current I is performed directly from the air cleaning device 15 (see stream I in the upper part of FIG. 8 ).

In FIG. 9 In particular, the operation of a regeneration gas preheater 152 according to one embodiment of the invention is illustrated. The Regeneriergasvorheizeinrichtung 152 may for example replace or supplement a Nachkühleinrichtung 17 and thus be disposed downstream of an air compressor 16. A heated air stream due to a corresponding compression can be passed through or past a heat exchanger 152a of the regeneration gas preheater 152 and thereby transfer heat to a regeneration gas flow k.

In the Figures 10A and 10B Air cleaning devices 15 are shown, which are particularly suitable for in the FIGS. 3A and 3B illustrated embodiments of the present invention or the air conditioning devices shown in these are suitable. In the Figures 10A and 10B are the energy storage period ( Figure 10A ) and the energy recovery period ( FIG. 10B ), wherein in the energy storage period, a purification of a corresponding current s takes place. Because no air in the form of the flow a is supplied to the energy recovery period of a corresponding installation 100 and thus the air conditioning device 10 is not in operation, a corresponding adsorber tank 151 is located in such times ( FIG. 10B ) for regeneration. The in the Figures 10A and 10B illustrated embodiment therefore has the particular advantage that only a corresponding adsorber 151 must be provided and not two, according to FIG. 8 be operated in alternation.

Again, a Regeneriergasstrom k in an optional Regeneriergasvorheizeinrichtung (not shown), preheated and in a Regeneriergasheizeinrichtung 153 are heated. The Regeneriergasheizeinrichtung 153 can be operated in particular by means stored in the heat storage unit 13 heat (not shown).

In the in the FIG. 10B illustrated energy recovery period is thus performed according heated heated regeneration gas through the adsorber tank 151, in the energy storage period ( Figure 10A ) is this Regeneriergasbehälter 151 for the purification of the current s available.

The FIGS. 11A to 11C illustrate plants according to preferred embodiments of the invention in each case in the energy storage period. With regard to the fixed-bed cold storage unit 20, the cold-extraction unit 40, the liquid-storage unit 50 and the energy-generating unit 60, the installations essentially correspond to the previously explained embodiments, but differ in particular with regard to the countercurrent heat-exchange unit 30, which is therefore explained below.

According to the in Figure 11A illustrated embodiment, the countercurrent heat exchange unit 30 can be operated for example by means of a current u, which is guided from the cold end to the warm end by one or more heat exchangers 31 of the countercurrent heat exchange unit 30.

For example, to provide the current u, a separate liquefaction process 32 implemented by means of its own, i. in addition to the air conditioning unit 10 provided, compressor is operated.

In the in FIG. 11B shown embodiment, which is substantially in the Figures 1A and 1B On the other hand, the countercurrent heat exchange unit 10 can be supplied with a medium-pressure air flow j and fed into the heat exchanger 31 at the warm end. The current j can be taken from the heat exchanger 31 at an intermediate temperature and relaxed in a generator turbine 33. Another partial flow of the high-pressure air flow b or its partial flow d can likewise be taken from the heat exchanger 131 at an intermediate temperature and expanded in a further generator turbine 34. The streams mentioned can be combined and be performed together through the generator turbine 33. Refrigeration liberated by the relaxation is used to liquefy the stream c (see Figures 1A and 1B ) are used by appropriate currents are supplied to the heat exchanger 31 together with the already explained flow i cold side.

In an in FIG. 11C the current i is fed to the heat exchanger 31 of the countercurrent heat exchange unit 30 cold side, taken at an intermediate temperature, with the medium pressure air flow j, which was also led to an intermediate temperature through the heat exchanger 31, and then relaxed in the generator turbine 33. Beforehand, corresponding air can be combined with a partial stream of the stream c, as already in FIG. 11B shown.

The in the FIGS. 11B and 11C illustrated embodiments are particularly suitable for the use of existing at different pressure levels currents i.

Claims (12)

A method of storing and recovering energy, wherein an air liquefaction product (LAIR) is formed in an energy storage period and a pressure stream is formed and work expanded in an energy recovery period using at least a portion of the air liquefaction product (LAIR) without heat input from an external heat source, the method includes,
for the formation of the air liquefaction product (LAIR) To compress air (AIR) in an air conditioning unit (10) at least by means of an adiabatically operated compressor device (12) and to adsorptively clean it by means of at least one adsorptive cleaning device (15) at a superatmospheric pressure level, - In the air conditioning unit (10) downstream of the adiabatically operated compressor device (12) from the compressed air in this (AIR) to form a first and a second partial flow and the first and the second partial flow in parallel by a first heat storage device (131) and a second To carry heat storage device (132), to store heat generated in the compression of the air (AIR) at least in part in the first heat storage device (131) and the second heat storage device (132), - The compressed and adsorptively purified air (HPAIR) from a temperature level in a range of 0 to 50 ° C to a first portion in a fixed bed cold storage unit (20) and a second portion in a countercurrent heat exchange unit (30) at a condensing pressure level in a range from 40 to 100 bara to liquefy, and to subsequently relax the liquefied air (HPLAIR) in at least one refrigeration unit (40), and for the formation of the pressure stream from at least part of the liquefaction product (LAIR) at a deflagration pressure level which does not deviate from the condensing pressure level by more than 5 bar to produce a defrosting product (HPAIR) in the fixed bed cold storage unit (20), such as - To guide the pressure flow in the work-relaxation by a first expansion device (61) and a second expansion device (62) and to relax the pressure flow in each case, and transferring heat stored upstream of the first expansion device (61) in the first heat storage device (131) to the pressure flow and transferring heat stored upstream of the second expansion device (62) in the second thermal storage device (132) to the pressure flow. The method of claim 1, comprising using in at least one of the heat storage devices (131, 132) a fixed bed (1) and / or liquid heat storage medium. The method of claim 1 or 2, comprising transferring in at least one of the heat storage devices (131, 132) a heat storage fluid between at least two storage tanks (72, 74) and transferring the heat in at least one heat exchanger (71) from or to the at least one heat storage device (71) Transfer heat storage fluid. Method according to one of the preceding claims, comprising, in at least one of the heat storage devices (131, 132) to heat a heat storage medium to a temperature level of 50 to 400 ° C. Method according to one of the preceding claims, in which a generator turbine is used in each case as the first expansion device (61) and as the second expansion device (62). Method according to one of the preceding claims, comprising supplying to the at least one adsorptive cleaning device (15) a regeneration gas which is formed from a part of the previously compressed air in the air conditioning unit (10) and adsorptively purified air (HPAIR). A method according to claim 6, comprising forming the regeneration gas during the energy storage period from at least part of an evaporation product formed during the expansion of the liquefied air (HPLAIR). The method of claim 6, comprising forming the regeneration gas from at least a portion of the defrosting product (HPAIR) during the energy recovery period. A method according to any one of the preceding claims, comprising passing an evaporation product formed by the expansion of the liquefied air (HPLAIR) through the countercurrent heat exchange unit (30). Method according to one of the preceding claims, comprising guiding at least one coolant through the countercurrent heat exchange unit (30) provided by means of an external refrigeration cycle and / or by venting from a part of the air previously compressed and adsorptively cleaned in the air conditioning unit (10) ( AIR) is formed. An apparatus (100) for storing and recovering energy by forming an air liquefaction product (LAIR) in an energy storage period and generating and work-releasing a pressure stream using at least a portion of the air liquefaction product (LAIR) without heat input from an external heat source in an energy recovery period is set up, wherein the system (100) has means that are set up
for the formation of the air liquefaction product (LAIR) To compress air (AIR) in an air conditioning unit (10) at least by means of an adiabatically operated compressor device (12) and to adsorptively clean it by means of at least one adsorptive cleaning device (15) at a superatmospheric pressure level, - In the air conditioning unit (10) downstream of the adiabatically operated compressor device (12) from the compressed air in this (AIR) to form a first and a second partial flow and the first and the second partial flow in parallel by a first heat storage device (131) and a second To carry heat storage device (132), to store heat generated in the compression of the air (AIR) at least in part in the first heat storage device (131) and the second heat storage device (132), - The compressed and adsorptively purified air (HPAIR) from a temperature level in a range of 0 to 50 ° C to a first portion in a fixed bed cold storage unit (20) and a second portion in a countercurrent heat exchange unit (30) at a condensing pressure level in a range from 40 to 100 bara to liquefy, and to subsequently relax the liquefied air (HPLAIR) in at least one refrigeration unit (40), and for the formation of the pressure stream from at least part of the liquefaction product (LAIR) at a deflagration pressure level which does not deviate from the condensing pressure level by more than 5 bar to produce a defrosting product (HPAIR) in the fixed bed cold storage unit (20), such as - To guide the pressure flow in the work-relaxation by a first expansion device (61) and a second expansion device (62) and to relax the pressure flow in each case, and transferring heat stored upstream of the first expansion device (61) in the first heat storage device (131) to the pressure flow and transferring heat stored upstream of the second expansion device (62) in the second thermal storage device (132) to the pressure flow. Plant (100) according to claim 11, comprising means adapted to carry out a method according to any one of claims 1 to 10.

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