CN104136875A - Regenerator - Google Patents

Abstract

The present invention relates to a regenerator comprising a bed (11) of energy storage media (12) placed in a chamber (14), the chamber comprising a shell (34) and a protective layer (22) placed between said shell and said energy storage media, in contact with said energy storage media, having a minimum thickness higher than 50 mm and consisting, at least partially, of a protective material having a composition, in weight percent based on the oxides, such that: - Fe2O3+ Al2O3+ CaO + TiO2+ SiO2+ Na2O + K2O > 80%, and - other oxides: complement to 100%.

Description

accumulator

technical field

The invention relates to a heat storage regenerator and to a thermal installation comprising the regenerator.

Background technique

The storage of energy (eg thermal energy) to vary the production and consumption of said energy in time.

Thermal energy storage can also be used to harness soft energy sources, such as solar energy, which are renewable but generated intermittently. Energy storage can also be used to take advantage of electricity prices between "off-peak" hours (during which electricity rates are lowest) and "peak" hours (during which electricity rates are highest) difference. For example, in the case of compressed air energy storage that generates thermal energy that is stored in thermal accumulators, the compression phase that consumes electricity is advantageously performed at the lowest cost during off-peak hours, while the expansion phase that generates electricity is performed during peak This is done over time in order to provide electricity that can be injected into the transmission grid as needed, at favorable electricity rates.

Conventionally, thermal energy is stored in a packed bed of energy storage medium of the regenerator, eg in a bed of pebbles.

The storage operation by heat exchange between the heat transfer fluid flow and the regenerator is conventionally referred to as the "charging phase", and the heat transfer fluid entering the regenerator during charging is referred to as charging heat transfer fluid.

The transfer of thermal energy can cause an increase in the temperature of these energy storage media (obvious heat storage) and/or a phase change of these media (latent heat storage).

The stored thermal energy can then be restored by heat exchange between the heat transfer fluid flow and the energy storage medium. Conventionally, this operation is called the discharge phase, the heat transfer fluid entering the accumulator during the discharge period is called the discharge heat transfer fluid, and the time elapsed between the end of the charge phase and the start of the discharge phase is called the storage time .

"A review on packed bed solar energy storage systems", Renewable and Sustainable Energy Reviews, 14 (2010), pp. 1059-1069, describes the state of the art in the field of regenerators.

During operation of the heat accumulator, especially when the heat transfer fluid is moist air, condensation of moisture in the air corrodes the material of the heat accumulator. Furthermore, at high pressure, the moisture present in the air can condense and mix with other condensates or pollutants present. Then, other condensate or pollutants can make the water acidic and therefore corrosive. This leads to a considerable reduction in the service life of the heat accumulator (in industrial installations this should be longer than 20 years, or even longer than 30 years) and thus to an increase in the overall costs.

Therefore, there is a need to increase the service life of regenerators, especially with regard to aggressive acid corrosion, especially at operating temperatures above 350°C, or even above 500°C, especially for accumulators charged with humid air. heater.

It is an object of the present invention to at least partially meet this need.

Contents of the invention

According to the invention, this object is achieved with a heat accumulator, in particular a sensible heat accumulator, comprising a bed of energy storage medium placed in a chamber comprising a housing and placed between said housing and A protective layer between said energy storage medium, said protective layer being in contact with said energy storage medium, has a minimum thickness greater than 50 mm and at least partially, preferably completely, comprises a protective material, in weight percent based on oxide , the composition of the protective material satisfies:

- Fe ₂ O ₃ +Al ₂ O ₃ +CaO+TiO ₂ +SiO ₂ +Na ₂ O+K ₂ O>80%, and

-Other oxides: replenished to 100%.

The inventors have found that heat accumulators according to the invention have a longer service life, especially in applications according to the invention in which the energy storage medium is in contact with an acidic liquid.

In the first embodiment, the material of the protective layer or the composition of the protective material preferably satisfies:

- Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ >80%, preferably Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ >90%, and/or

- Al ₂ O ₃ >60%, preferably Al ₂ O ₃ >85%, preferably Al ₂ O ₃ >95%, and/or

- _Fe2O3 <20% _, preferably _Fe2O3 <10% _, preferably _Fe2O3 <3%, and _/ or

- SiO ₂ <10%, preferably SiO ₂ <5%, preferably SiO ₂ <2%, and/or

- CaO<2%, preferably CaO<1%, preferably CaO<0.5%, and/or

- Na ₂ O+K ₂ O<0.5%, preferably Na ₂ O+K ₂ O<0.3%, preferably Na ₂ O+K ₂ O<0.2%.

In the second embodiment, the composition of the protective material preferably satisfies:

-25 _% < _Fe2O3 <70%, _{preferably Fe2O3} >40%, and

_-5 %< _Al2O3 <30%, preferably _Al2O3 <20% _, and

- CaO<20%, preferably CaO>3%, and

- TiO ₂ <25%, preferably TiO ₂ >5%, and

- 3% < SiO ₂ < 50%, preferably SiO ₂ > 5% and/or SiO ₂ < 20%, and

- _Na2O + _K2O <10%, preferably _Na2O + _K2O <5%, and

- Other oxides < 5%, preferably other oxides < 3%.

Preferably, the majority of compounds of the protective material are selected from the group consisting of alumina, bauxite, spinel MgAl ₂ O ₄ , mullite, hessianite CaAl ₁₂ O ₁₉ , aluminum titanate, and combinations thereof.

Even more preferably, the protective material has:

- an open porosity of less than 20%, preferably less than 10%, preferably less than 5%, and

- a compressive strength higher than 50 MPa, preferably higher than 70 MPa, preferably higher than 90 MPa, and

- pyroscopic resistance above 350°C, preferably above 700°C, preferably above 900°C.

Preferably, the minimum thickness of the protective layer is greater than 100 mm, preferably greater than 150 mm.

Preferably, the protective layer is penetrated by holes.

The protective layer is also used to place the insulation inside the case, between the case and the protective layer. Advantageously, the insulating layer, like the casing, is protected by a protective layer. Thus, the protective layer can help maintain the insulating layer in place. Therefore, the properties of the insulating layer (type of insulating layer, thickness of insulating layer, form of insulating layer, etc.) are not guided as necessary to resist the stress applied in the chamber.

For the chamber it is particularly advantageous to include a protective layer and an insulating layer, both layers helping to give the heat accumulator a high efficiency and a long service life.

Preferably, an insulating layer extends between the outer shell and the protective layer, the thermal resistance R _I of the insulating layer is greater than 0.1 m ² ·K/W, preferably greater than 0.2 m ² ·K/W, preferably greater than 0.3 m ² ·K/W, Preferably greater than 0.4 m ² ·K/W, or even greater than 1 m ² ·K/W, or even greater than 1.5 m ² ·K/W, or even greater than 2 m ² ·K/W, or even greater than 2.2 m ² ·K/W W.

The insulating layer comprises, or even consists of, a material known as insulating material. Preferably:

- the thermal conductivity of the insulating material is lower than 2 W/m·K, preferably lower than 1.5 W/m·K, and/or

- the mechanical compressive strength of the insulating layer is greater than 1 MPa, preferably greater than 2 MPa, preferably greater than 5 MPa, and/or

- The insulating material has a coefficient of linear thermal expansion measured at 500° C. of less than 0.5%, preferably less than 0.4%.

Preferably, the minimum thickness of the insulating layer is greater than 150mm, preferably greater than 300mm.

Even more preferably,

- the insulating material has a silicon dioxide content of less than 50%, preferably less than 10%, preferably less than 1%, and/or

- the CaO content of the insulating material is less than 10%, preferably less than 5%, preferably less than 2%, and/or

- the alumina content of the insulating material is higher than 40%, preferably higher than 60%, preferably higher than 80%.

Preferably, the majority of compounds of the insulating material are selected from corundum, spinel MgAl ₂ O ₄ , calcined clay, mullite, hessianite CaAl ₁₂ O ₁₉ , aluminum titanate, bauxite, and combinations thereof.

It is also particularly advantageous to have an intermediate layer between the protective layer and the insulating layer to facilitate sliding and to accommodate differences in thermal expansion between the protective layer and the insulating layer.

Preferably, the intermediate layer has a maximum thickness below 10mm and preferably comprises, or even consists of, a fibrous material.

Preferably, the intermediate layer comprises alumina in a content greater than 30%, preferably greater than 70%, preferably greater than 90%.

Preferably, the thermal resistance R _PI of the intermediate layer is greater than 0.05 m ² ·K/W, preferably greater than 0.1 m ² ·K/W.

The weight of the bed may be greater than 700 tonnes.

The invention also relates to a thermal device comprising:

- units that generate heat, such as furnaces, solar towers, compressors, and

- a heat accumulator according to the invention, and

- Circulation means which, during the charging phase, circulate the charging heat transfer fluid from the thermal energy generating unit to the heat accumulator and then through said heat accumulator.

In an embodiment, the heat transfer fluid from said thermal energy generating unit is condensed in said regenerator in the form of an acidic liquid, and/or at temperatures below 1000°C and above 350°C, or even below 800°C And the temperature higher than 500°C enters the heat accumulator.

The heat accumulator according to the invention is particularly suitable under these conditions.

The unit that generates thermal energy may include a compressor.

In an embodiment, the thermal device further comprises a thermal energy consumption unit, and the circulation means, during the release phase, circulate the released heat transfer fluid through said heat accumulator and then from said heat accumulator to the thermal energy consumer unit. The thermal energy consumer may comprise a turbine.

The invention also relates to a method for operating a thermal installation according to the invention, adjusting the insulation of the heat accumulator so that, under operating conditions, the heat loss from the heat accumulator is low at the end of the charging cycle and discharge cycle At 10%, that is to say, the energy recovered at the end of the discharge phase is higher than 90% of the total energy injected into the heat accumulator at the end of the charge phase. Preferably, these losses are less than 8%, preferably less than 5%, preferably less than 3%, preferably less than 1%, preferably the storage time is less than 48 hours, preferably less than 24 hours.

Description of drawings

Other objects, aspects, properties and advantages of the present invention will further appear from the ensuing description and examples and review of the accompanying drawings, in which:

- Figures 1a and 1b schematically show the thermal device according to the invention during the charging phase and the releasing phase, respectively;

- Figure 2 schematically shows the heat accumulator of the thermal device in Figure 1;

- Figure 3 shows a perspective view of a part of the side wall of the heat accumulator in Figure 2 .

In the various drawings, the same reference numerals are used to designate the same or similar parts.

definition

A "heat generating unit" refers not only to a unit specifically designed to generate heat, like a solar tower, but also to a unit that generates heat when in operation, like a compressor.

The term "thermal device" should also be understood in a broad sense to mean any device comprising a unit for generating thermal energy.

The term "thermal energy consuming unit" denotes an element capable of receiving thermal energy. In particular, the element can increase the temperature of the consumer unit (for example, in the case of heating a building) and/or convert it into mechanical energy (for example, in a gas turbine).

In the present description, for the sake of clarity, the terms "charging heat transfer fluid" and "releasing heat transfer fluid" mean the heat transfer fluid flowing in the heat accumulator during the charging phase and during the discharging phase, respectively.

A "bed" of energy storage media means a group of such media at least partially overlapping each other.

"Preform" conventionally refers to a group of particles, usually temporarily connected by a binder, the microstructure of which develops during sintering.

"Sintering" means a heat treatment by which particles of a preform are processed to form a matrix that holds together other particles of the preform.

For clarity, the term "red mud" means the liquid or slurry by-product resulting from the process used to produce alumina and the corresponding dry product.

According to common practice in the industry, the oxide content is related to the total content for each corresponding chemical element expressed in the most stable oxide form.

All percentages are by weight based on oxide unless otherwise stated.

"Containing a" or "comprising a" means "comprising at least one", unless otherwise specified.

Detailed ways

thermal device

As shown in FIG. 1 , the thermal device 2 according to the invention comprises a thermal energy generating unit 4 , optionally a thermal energy consuming unit 6 , a circulation device 7 , optionally a cavity not shown, and a heat accumulator 10 .

A thermal energy generating unit 4 may be used to generate thermal energy, eg a furnace or a solar tower.

Said circulation means circulates, during the charging phase, a charging heat transfer fluid from the thermal energy generating unit to the heat accumulator and then through said heat accumulator.

In an embodiment, the unit generating thermal energy comprises or even consists of a compressor, for example, from an incineration plant or a power plant, in particular a thermal, solar, wind, hydro or tidal power plant, Compressors supplied mechanically or electrically.

Compression of a gaseous fluid, preferably an adiabatic gaseous fluid, causes the storage of energy therein by increasing its pressure and its temperature.

The energy generated by the increase in pressure can be stored by storing the pressurized fluid. The recovery of this energy can be derived from expansion, for example in a turbine.

The energy generated by the increase in temperature can be stored in the heat accumulator according to the invention. The recovery of this energy then results from the heat exchange with the heat accumulator.

Thermal energy may be a by-product of production, that is, may not be so desired.

Preferably, the thermal energy generating unit generates more than 50 kW, or even more than 100 kW of thermal energy, or even more than 300 kW, or even more than 1 MW, or even more than 5 MW of thermal energy. In fact, the invention is particularly useful in high volume industrial installations.

The unit for generating thermal energy may comprise a heat exchanger suitable for direct or indirect heat exchange with a heat accumulator.

Preferably, the thermal installation according to the invention comprises a thermal energy consumer unit 6, said circulation means circulating the released heat transfer fluid through said heat accumulator and then from said heat accumulator to the thermal energy consumer unit during the release phase.

In particular, the thermal energy consumer unit 6 may be a building or group of buildings, a reservoir, a water tank, a turbine coupled to a generator for generating electricity, an industrial plant consuming steam (eg a pulp manufacturing plant).

In the embodiment shown, the thermal energy consumption unit 6 comprises a heat exchanger 6a adapted to flow between the discharge heat transfer fluid ( FIG. 1b ) and the secondary heat transfer fluid produced by the heat accumulator 10 Heat exchange is performed between the secondary lines 6b. The secondary line is configured for carrying out heat exchange between the heat exchanger 6a and, for example, the building 6c.

The circulation device 7 comprises a charging line 7a and a releasing line 7b through which a charging heat transfer fluid and a releasing heat transfer fluid can flow respectively. These charging and discharging lines are used to carry out heat exchange between the thermal energy generating unit 4 and the heat accumulator 10 during the charging phase and between the heat accumulator 10 and the thermal energy consuming unit 6 during the discharging phase, respectively. heat exchange.

Conventionally, the circulation unit 7 includes a set of lines, valves and controlled pumps/blowers/extractors to allow the accumulator 10 to selectively

- communicated with the unit generating thermal energy, so that the regenerator, during the charging phase (line 7a), can receive charging heat transfer fluid leaving said unit, and

- communicated with a thermal energy consuming unit such that during the releasing phase (line 7b), the heated releasing heat transfer fluid leaving the regenerator can transfer thermal energy to said consuming unit,

And, in order to cause the charge heat transfer fluid and/or discharge heat transfer fluid to flow through the heat accumulator.

The temperature of the charging heat transfer fluid entering the regenerator during the charging phase is preferably below 1000°C, or even below 800°C, and/or preferably above 350°C, or even above 500°C.

The charging heat transfer fluid and the discharging heat transfer fluid may or may not be of the same type.

The charge heat transfer fluid and/or discharge heat transfer fluid may be a gas, such as air, steam, or heat transfer gas, or may be a liquid, such as water or thermal oil.

In an embodiment, the energy storage medium is permanently or temporarily in contact with an acidic liquid having a pH below 6, or even below 5.5, or even below 5, or even below 4.5, or even below 4 , in particular, the acidic liquid is aqueous. In fact, under these conditions, the invention is particularly advantageous.

However, the present invention is not limited to a particular heat transfer fluid.

Preferably, in particular, when the charging heat transfer fluid and the discharging heat transfer fluid are of the same type, and when the charging heat transfer fluid (eg air) has been subjected to an increase in pressure (eg to 50 bar, or Even for temperature increases of 100 bar, or even 150 bar), the thermal device may comprise a cavity for temporary storage of cooled heat transfer fluid-filled flow from the heat accumulator. The volume of the cavity is usually greater than ^20000m3 , or even greater than ^100000m3 .

The cavity preferably has low permeability, or even is impermeable to the filling of the heat transfer fluid.

The heat accumulator 10 shown in more detail in FIG. 2 comprises a bed 11 of energy storage medium 12 placed in a chamber 14 .

bed of energy storage medium

Preferably, the heat accumulator is a sensible heat accumulator, that is to say the material of the energy storage medium and the filling and discharge temperature are determined such that the energy storage medium remains solid during operation of the thermal device. In fact, the probability of condensation of the heat transfer fluid is highest in sensible heat accumulators.

Preferably, the material of the energy storage medium incorporates residues from the production of alumina, in particular by the Bayer process, described in particular in "Les techniques de l'ingénieur" of the edition T.I., published on January 10, 1992 , article "métallurgie extractive de l'aluminium", number M2340 (in particular chapter 6 starting on page M2340-13 and Figure 7 on page M2340-15).

Preferably, the energy storage medium is obtained by sintering a shaped preform resulting from an initial charge comprising more than 10%, preferably more than 30%, preferably More than 50%, preferably more than 60%, preferably more than 70%, preferably more than 80% of the red mud resulting from the implementation of the Bayer process. The red mud may optionally be converted prior to use, for example during a washing step and/or a drying step.

Preferably, the energy storage medium has the following chemical analysis in terms of weight percentage based on oxides, and the total is 100%:

-25%< _{Fe2O3 <} 70%, preferably _Fe2O3 <65%, or even _Fe2O3 <60% _, and _/ or preferably _Fe2O3 >30%, _{preferably Fe2O3} >35 _% %, preferably Fe ₂ O ₃ >40%, or even Fe ₂ O ₃ >45%, or even Fe ₂ O ₃ >50%, and

_-5 %< _Al2O3 <30%, preferably _Al2O3 <20% _, and

-CaO<20%, and

- _TiO2 < 25%, preferably _TiO2 < 20%, preferably _TiO2 < 15%, and

-3%< _SiO2 <50%, preferably _SiO2 <40%, preferably _SiO2 <30%, preferably _SiO2 <20%, preferably _SiO2 <15%, and

- _Na2O + _K2O <10%, or even _Na2O + _K2O <5%, and

-Fe ₂ O ₃ +Al ₂ O ₃ +CaO+TiO ₂ +SiO ₂ +Na ₂ O+K ₂ O>80%, preferably Fe ₂ O ₃ +Al ₂ O ₃ +CaO+TiO ₂ +SiO ₂ +Na ₂ O+K ₂ O >85%, or even Fe ₂ O ₃ +Al ₂ O ₃ +CaO+TiO ₂ +SiO ₂ +Na ₂ O+K ₂ O >90%, or even Fe ₂ O ₃ +Al ₂ O ₃ +CaO+TiO ₂ +SiO ₂ +Na ₂ O+K ₂ O >95%, and

-Other oxides: replenished to 100%.

Preferably, the energy storage medium comprises more than 90%, preferably more than 95%, preferably more than 99% oxide.

Preferably, the energy storage medium is made of a sintered material, preferably at a temperature between 1000°C and 1500°C, at which temperature, preferably during a holding time longer than 0.5 hours and preferably shorter than 12 hours, and preferably after oxidation atmosphere, preferably air, while being sintered.

The shape and size of the energy storage medium 12 are not limited. Preferably however, the smallest dimension of the energy storage medium is greater than 0.5 mm, or even greater than 1 mm, or even greater than 5 mm, or even greater than 1 cm and/or preferably less than 50 cm, preferably less than 25 cm, preferably less than 20 cm, preferably less than 15 cm. Preferably, the largest dimension of the energy storage medium is less than 10 meters, preferably less than 5 meters, preferably less than 1 meter.

In particular, like those described in US 6,889,963 and/or in US 6,699,562, the energy storage medium 12 may have the shape of balls and/or granules and/or solid bricks and/or open bricks, and/or ten Glyph elements and/or double cross elements and/or solid elements and/or through-hole elements.

The energy storage medium is assembled in the chamber 14 so as to constitute the bed 11 .

The bed may be organized, for example by bonding the energy storage medium, or may be disorganized ("block"). For example, the bed may be in the form of a mass of crushed fractions (without any particular shape, such as a mass of pebbles).

The height of the bed is preferably greater than 1 m, preferably greater than 5 m, preferably greater than 15 m, preferably greater than 25 m, or even greater than 35 m, or even greater than 50 m.

The weight of the bed is preferably greater than 700T, preferably greater than 2000T, preferably greater than 4000T, preferably greater than 5000T, preferably greater than 7000T.

room

Chamber 14 has a top opening 16 and a bottom opening 18 .

In an embodiment, the opening of the regenerator through which the charging heat transfer fluid enters the regenerator during the charging phase is the opening through which the heated discharge heat transfer fluid leaves the regenerator during the discharging phase. Conversely, the opening of the regenerator through which the discharge heat transfer fluid to be heated enters the regenerator during the discharge phase is the opening through which the cooled charge heat transfer fluid leaves the regenerator during the charge phase .

Preferably, the opening of the regenerator through which the released heat transfer fluid to be heated enters the regenerator is the bottom opening 18 of the regenerator.

Preferably, the opening of the regenerator through which the heated release heat transfer fluid leaves the regenerator is the top opening 16 of the regenerator.

Chamber 14 conventionally includes a housing 20, which is typically metallic, eg, made of stainless steel or carbon steel. The enclosure may also comprise the walls of a natural cavity or an artificially dug cavity, optionally with an inner liner for reinforcing said walls and/or for leveling the surfaces in contact with the energy storage medium. In particular, the walls of the natural cavity may be rock. Preferably, chamber 14 comprises a metal housing.

In particular, if the heat accumulator is buried, a cooling system, not shown, can be provided outside the enclosure. For example, the system may circulate air or liquid, especially water.

According to the invention, the housing 20 is internally protected by a protective layer 22 in contact with the energy storage medium.

The protective layer

The material of the protective layer or the composition of the protective material is as follows:

- preferably Fe ₂ O ₃ +Al ₂ O ₃ +CaO+TiO ₂ +SiO ₂ +Na ₂ O+K ₂ O >85%, or even Fe ₂ O ₃ +Al ₂ O ₃ +CaO+TiO ₂ +SiO ₂ + _Na2O + _K2O >90%;

- preferably Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ >50%, preferably Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ >60%, or even Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ > 70%, or even Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ >80%, Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ >90%, Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ >95%;

- Preferably, MgO, P ₂ O ₅ and mixtures thereof comprise more than 90%, more than 95%, or even substantially 100% of the other oxides.

In a first preferred embodiment:

- Al ₂ O ₃ >60%, preferably Al ₂ O ₃ >70%, preferably Al ₂ O ₃ >80%, preferably Al ₂ O ₃ >85%, preferably Al ₂ O ₃ >90%, or even Al ₂ O ₃ >95%, or even Al ₂ O ₃ >98%, or even Al ₂ O ₃ >99%. Advantageously, the resistance to attack by aggressive chemical agents that may be contained in the heat transfer fluid, as well as the dimensional stability are thus increased;

- _{Fe2O3 <} 20%, preferably _Fe2O3 <15%, preferably _Fe2O3 <10%, preferably _{Fe2O3 < 5} %, _{preferably Fe2O3 < 3} %, preferably _Fe2O3 <1%;

- _SiO2 <10%, preferably _SiO2 <8%, preferably _SiO2 <7%, preferably _SiO2 <5%, or even _SiO2 <4%, or even _SiO2 <3%, or even _SiO2 <2 %. Advantageously, degradation by any vapors that may be contained in the heat transfer fluid is thus reduced;

- CaO<2%, preferably CaO<1%, preferably CaO<0.5%. Advantageously, degradation due to carbonation caused by the reaction of CaO with _CO that may be contained in the heat transfer fluid is thus reduced;

- the protective material does not have a binder based on CaO-containing cement;

- Na ₂ O+K ₂ O<0.5%, preferably Na ₂ O+K ₂ O<0.3%, preferably Na ₂ O+K ₂ O<0.2%. Advantageously, degradation of the protective material due to the formation of products subjected to swelling, in particular due to the presence of steam in the heat transfer fluid, is thus reduced.

In the second embodiment, the protective material may have one or more of the following optional features:

- In terms of weight percentages based on oxides, and the total is 100%, the protective material has the following composition:

-25% < Fe ₂ O ₃ < 70%, and

-5% < Al ₂ O ₃ < 30%, and

-CaO<20%, and

-TiO ₂ <25%, and

-3% < SiO ₂ < 50%, and

-Na ₂ O+K ₂ O<10%, and

-Other oxides <5%.

- the _Fe2O3 content of the protective material is preferably greater than 30%, preferably greater than 35%, preferably greater than 40%, or even greater than 45%, or even greater than 50%, or even greater than 60%, and/or preferably less _than 65%.

- Fe ₂ O ₃ +Al ₂ O ₃ >40%, preferably Fe ₂ O ₃ +Al ₂ O ₃ >50%, or even Fe ₂ O ₃ +Al ₂ O ₃ >60%, or even Fe ₂ O ₃ + Al ₂ O ₃ >70%;

- the Al ₂ O ₃ content of the protective material is preferably less than 25%, preferably less than 20%;

- the CaO content of the protective material is preferably greater than 3%, or even greater than 5%, or even greater than 10%;

- the _TiO2 content of the protective material is preferably greater than 5%, or even greater than 10%, and/or preferably less than 20%, preferably less than 15%;

- the _SiO2 content of the protective material is preferably greater than 5%, or even greater than 8%, and/or less than 40%, preferably less than 30%, preferably less than 20%, preferably less than 15%;

- the Na ₂ O+K ₂ O content of the protective material is preferably less than 5%;

- said protective material preferably has a content of "other oxides" of less than 3%, or even less than 2%, expressed in weight percentages based on oxides;

- Preferably, the protective material comprises more than 90%, preferably more than 95%, preferably more than 99%, or even substantially 100% oxides in weight percent.

Preferably, the main compound of the protective material is selected from alumina, in particular corundum, bauxite, spinel MgAl ₂ O ₄ , mullite, heselite CaAl ₁₂ O ₁₉ , aluminum titanate, and combinations thereof, Corundum, bauxite, and spinel MgAl ₂ O ₄ are preferred.

The open porosity of the protective material is preferably less than 20%, preferably less than 18%, preferably less than 15%, preferably less than 12%, preferably less than 10%, preferably less than 8%, preferably less than 6%, preferably Below 5%, or even below 4%, or even below 3%.

The compressive strength of the protective material is preferably higher than 50 MPa, preferably higher than 60 MPa, preferably higher than 70 MPa, or even higher than 90 MPa. Advantageously, the resistance to puncture of the energy storage medium is thus increased, especially when the energy storage medium is placed in piles, thus reducing mechanical damage to the protective layer and increasing the service life of the heat accumulator.

The protective material preferably has a heat-resistant temperature higher than the temperature of the heat transfer fluid entering the regenerator during charging. Preferably, the heat-resistant temperature of the protective material is higher than 350°C, higher than 500°C, higher than 700°C, higher than 800°C, higher than 900°C, higher than 1000°C.

Those skilled in the art know how to modify open porosity, compressive strength and heat resistance temperature.

The minimum thickness of the protective layer, preferably the average thickness, is preferably greater than 75mm, preferably greater than 100mm, preferably greater than 150mm, preferably greater than 180mm, and/or preferably less than 500mm, preferably less than 400mm, preferably less than 300mm, preferably less than 250mm.

The thickness of the protective layer and the type of protective material are preferably adjusted such that, especially when the heat transfer fluid is air and/or water vapor, the condensation isotherm lies in the thickness of the protective layer. Advantageously, the penetration of water is thus delayed and the service life of the heat accumulator is thus increased.

The protective material can be a molten product, a cast product or a sintered product. In particular, the protective material may be concrete (preferably self-cast), or mud brick (dry or wet). Preferably, the protective material is concrete.

The shaping of the protective material can take place by casting (especially vibratory casting), pressing (especially vibratory pressing, or isostatic pressing), ramming, extrusion, or a combination of these well-known techniques. Preferably, the forming process of the protective material results from vibration casting or pressing.

As shown in Figure 3, the protective material preferably comprises an array of shaped members or "blocks", the shape of which blocks is not limited.

For example, the protective layer may have the form of an assembly of annular blocks superimposed on each other.

Preferably, as shown in Figure 3, the bricks have complementary shapes enabling their nesting eg with grooved edges or raised edges.

Preferably, the blocks are joined, preferably by means of a joining material such as grout, mortar or mud, joining techniques being well known to those skilled in the art.

Preferably, the joining material has a content of aluminum oxide higher than 80%, preferably higher than 85%, preferably higher than 90%, or even higher than 95%, in weight percent based on oxide.

In particular, if the heat accumulator is small, the protective layer can also be in one-piece form.

The protective layer can be produced in situ (in the heat accumulator) or not in situ shaping, in particular casting (the protective layer or its parts (blocks) are shaped before assembly in the heat accumulator). Preferably, the protective layer is formed in situ.

Preferably, the protective layer contains less than 10% water, preferably less than 7%, preferably less than 5%, or even less than 3%, or even less than 2%, or even less than 1% water. Advantageously, the temperature rise of the heat accumulator is thus accelerated.

In an embodiment, the hole 23 preferably penetrates the protective layer in the thickness direction of the protective layer. In particular, these holes can be made through the joint or through the block. For example the drilled holes may for example have an equivalent diameter of between 3 mm and 10 mm, for example 5 mm. Preferably, the holes are evenly distributed, eg at a ratio of one hole per block, eg in the center of each block, or according to a predetermined grid, eg a square grid with sides of 1 m.

Advantageously, these holes serve to equalize the pressure on either side of the protective layer. The service life of the protective layer is thus increased.

In another embodiment, the protective layer forms an impermeable barrier between the housing and the energy storage medium.

Preferably, an insulating layer 24 extends between the housing 20 and the protective layer 22 .

The thermal resistance R _I of the insulating layer is preferably greater than 0.1 m ² ·K/W, preferably greater than 0.2 m ² ·K/W, preferably greater than 0.3 m ² ·K/W, preferably greater than 0.4 m ² ·K/W, or even greater than 1 m ² ·K/W, or even greater than 1.5 m ² ·K/W, or even greater than 2 m ² ·K/W, or even greater than 2.2 m ² ·K/W.

The thermal conductivity of the material of the insulating layer (referred to as "insulation material") is preferably greater than 20%, preferably greater than 50%, or even greater than 70% lower than that of the protective material. Preferably, the thermal conductivity of the insulating material is lower than 2 W/m·K, preferably lower than 1.5 W/m·K, preferably lower than 1 W/m·K. In a particular embodiment, the thermal conductivity of the insulating material is between 1 W/m·K and 1.5 W/m·K.

The minimum thickness, or even the average thickness, of the insulating layer is preferably greater than 150 mm, preferably greater than 200 mm, preferably greater than 300 mm, preferably greater than 400 mm, and/or less than 600 mm.

In a particular embodiment, the thermal conductivity of the insulating material is between 1 W/m·K and 1.5 W/m·K and the average thickness of the insulating layer is greater than 150 mm, preferably greater than 200 mm.

In a particular embodiment, the thermal conductivity of the insulating material is between 1.5 W/m·K and 2 W/m·K and the average thickness of the insulating layer is greater than 300 mm, preferably greater than 400 mm.

Preferably, the mechanical compressive strength of the insulating material is higher than 1 MPa, preferably higher than 2 MPa, or even higher than 3 MPa, or even higher than 5 MPa. Advantageously, the mechanical strength of the insulating material thus contributes to the mechanical strength of the heat accumulator wall.

The insulating material preferably has a linear coefficient of thermal expansion measured at 500°C below 15·10 ^-6 °C ^-1 , preferably below 10· ^10-6 °C ^-1 , or even below 8· ^10-6 °C ^-1 .

Those skilled in the art know how to modify the thermal conductivity, mechanical compressive strength and linear thermal expansion coefficient of insulating materials.

The insulating material preferably comprises more than 90%, preferably more than 95%, preferably more than 99%, preferably substantially 100% oxide by its mass.

Preferably, the insulating material is a ceramic material. Preferably, the insulating material has the following chemical composition in terms of weight percentage based on oxide: Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ +ZrO ₂ >60%, preferably Fe ₂ O ₃ +Al ₂ O ₃ + SiO ₂ +ZrO ₂ >70%, preferably Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ +ZrO ₂ >80%, preferably Fe ₂ O ₃ +Al ₂ O ₃ +SiO ₂ +ZrO ₂ >90%. Preferably, up to 100% of the complement comprises oxides, preferably selected from TiO ₂ , CaO, MgO, K ₂ O, Na ₂ O, P ₂ O ₅ , and mixtures thereof.

Preferably, the insulating material has a silicon dioxide content of less than 50%, or even less than 40%, or even less than 30%, or even less than 10%, or even less than 1% by weight based on oxide. %. Advantageously, corrosion caused by aggressive chemicals (eg caustic soda) which tend to condense in the thickness of the insulating layer is thus reduced.

Preferably, the insulating material has a CaO content of less than 10%, preferably less than 5%, preferably less than 2%, preferably less than 1%, in weight percent based on oxide. Advantageously, the carbonization sensitivity of the insulating material is thus reduced, thereby increasing the service life of the heat accumulator.

Preferably, the insulating material has an aluminum oxide content in weight percent based on oxide of higher than 40%, preferably higher than 50%, preferably higher than 60%, preferably higher than 65%, preferably higher than 70%, or even higher 80%, or even higher than 90%.

Preferably, the majority of compounds of the insulating material (components with the largest weight content) are selected from corundum, spinel MgAl ₂ O ₄ , calcined clay, mullite, hessite CaAl ₁₂ O ₁₉ , aluminum titanate, Bauxite, and combinations thereof.

The insulating material can be molten, cast or sintered. In particular, the insulating material may be concrete (preferably self-cast), mud blocks (dry or wet). Preferably, the insulating material is concrete. Preferably, the insulating material is a block of dry mud set by a ram, or preferably self-casting concrete.

The forming process of the insulating material can take place by casting (especially vibration casting), pressing (especially vibration pressing, or isostatic pressing), stamping, extrusion, or a combination of these well-known techniques. Preferably, the forming process of the insulating material results from vibration casting or pressing.

The insulating layer preferably comprises an array of shaped members, or "blocks", the shape of which blocks is not limited. Preferably, the blocks are joined, preferably by means of a joining material such as grout, mortar or mud. Preferably, the junction of the bulk of the insulating layer is offset relative to the junction of the protective layer. The protection of the housing is thus increased.

In particular, if the heat accumulator is small, the insulating layer can also be in the form of a single piece.

The insulating layer can be produced in situ (in the heat accumulator) or not in situ shaping, in particular casting (the insulating layer or its parts (blocks) are shaped before assembly in the heat accumulator). Preferably, the insulating layer is formed in situ.

Preferably, the insulating layer contains less than 10% water, preferably less than 7%, preferably less than 5%, or even less than 3%, or even less than 2%, or even less than 1% water. Advantageously, the temperature rise of the heat accumulator is thus accelerated.

Preferably, the intermediate layer 26 extends between the protective layer 22 and the insulating layer 24 . The interlayer serves to facilitate sliding, especially during filling and releasing cycles, and to accommodate differences in thermal expansion between the protective and insulating layers.

Preferably, as shown in FIG. 3 , the intermediate layer extends parallel to the outer face of the protective layer, preferably in contact with said outer face.

The middle layer may comprise or even consist of fibrous material, in particular cardboard and/or a mixture of interlaced fibers, preferably fibres, or even consist of a fibrous material, in particular cardboard and/or a mixture of interlaced fibres, preferably fibres. The fiber mixture is preferably in the form of a board and/or sheet, woven or non-woven. Preferably, the fibers are ceramic fibers.

The maximum thickness of the intermediate layer is preferably below 10 mm, preferably below 8 mm, preferably below 6 mm, preferably below 5 mm.

In an embodiment, the alumina content of the intermediate layer is higher than 30%, preferably higher than 50%, preferably higher than 70%, preferably higher than 80%, preferably higher than 90%, preferably higher than 95%, preferably higher than 99% %.

Preferably, the thermal resistance R _PI of the intermediate layer is higher than 0.05 m ² ·K/W, preferably higher than 0.1 m ² ·K/W.

In a preferred embodiment, the insulating layer is prepared in situ, after the protective layer has been placed, by filling the space remaining between said protective layer and the housing.

Preferably, prior to said filling, an intermediate layer is placed in this space, preferably in contact with the protective layer.

The walls of the chamber include an upper wall 30 , a lower wall 32 and side walls 34 . The protective layer, preferably the insulating layer and preferably the intermediate layer extends at least into the side wall 34 , preferably at least into the entire part of the side wall 34 facing the bed of the energy storage medium. They can also extend into the lower wall 32 and/or into the upper wall 30 .

In a particular embodiment, the heat accumulator comprises

○ A protective layer that has:

less than 20%, preferably less than 18%, preferably less than 15%, preferably less than 12%, preferably less than 10%, preferably less than 8%, preferably less than 6%, preferably less than 5%, or even an open porosity of preferably less than 4%, or even preferably less than 3%, and

a compressive strength higher than 50 MPa, preferably higher than 60 MPa, preferably higher than 70 MPa, even higher than 90 MPa, and

a heat-resistant temperature higher than 350°C, preferably higher than 700°C, preferably higher than 900°C, and

a thermal resistance R _P between 0.01 m ² ·K/W and 0.05 m ² ·K/W, and

○ an insulating layer having:

a compressive strength above 1 MPa, preferably above 2 MPa, or even 3 MPa, or even 5 MPa, and

• The insulating layer is made of an insulating material having a thermal resistance R _I higher than 0.20 m ² ·K/W, preferably higher than 0.43 m ² ·K/W, or even higher than 2.21 m ² ·K/W.

If R _(B) is higher than 0.20m ² ·K/W, the heat loss of the regenerator at the end of the charging cycle and discharge cycle is less than 10%, if R _(B) is higher than 0.43m ² ·K/ W, the heat loss is lower than 5%, and if R _(B) is higher than 2.21 m ² ·K/W, the heat loss is even lower than 1%.

run

The accumulator goes through a regular or irregular series of "cycles", each cycle comprising a charging phase, optionally a waiting phase, followed by a discharging phase. The duration of the periodic cycle is usually longer than 0.5 hours, or even longer than 2 hours, and/or shorter than 48 hours, or even shorter than 24 hours.

During the charging phase, the charging heat transfer fluid enters the regenerator at a temperature Tc (preferably substantially constant), and typically through the top opening 16 of the regenerator. Preferably, the temperature Tc of the charging heat transfer fluid entering the regenerator during its charging is below 1000°C, or even below 800°C, and/or preferably above 350°C, or even above 500°C.

The charging heat transfer fluid then continues its course in the regenerator (arrow in Fig. 1a) while heating the energy storage medium in contact with it. Therefore, the temperature of the charge heat transfer fluid gradually decreases.

When the charge heat transfer fluid is a gas, particularly in sensible heat accumulators, cooling of the charge heat transfer fluid can lead to condensation on the surface of the energy storage medium.

At high temperatures, like especially those considered above, the condensate can be highly corrosive.

During the discharge phase, the discharge heat transfer fluid enters the regenerator at a temperature Td (preferably substantially constant), usually through the top opening 18 of the regenerator. The heat transfer fluid then continues its course in the heat accumulator (arrow in Fig. 1b), while cooling the energy storage medium in contact with it. Therefore, the temperature of the heat transfer fluid gradually increases.

In an embodiment, the insulation of the regenerator is adjusted such that under operating conditions, at the end of the charging and discharging cycles, the heat loss of the regenerator is below 10%, preferably below 8%, preferably below 5%, or even less than 3%, or even less than 1%.

Example

The following examples are provided for illustrative purposes and are not limiting.

For example 2, after drying, the apparent density and open porosity were determined according to standard ISO5017.

Chemical analysis by X-ray fluorescence.

Compressive strength is determined according to standard EN993-5.

The heat resistance temperature is determined by the following method: ISO 1893 (collapse under load).

Determine the coefficient of thermal expansion by the following method: EN993-19.

The thermal conductivity of the material of the protective layer and the material of the insulating layer is determined by the following method: ISO8894-2.

The thermal conductivity of the material of the intermediate layer in the form of a fiber mat is measured according to the following standard: ASTM C-177.

The following assumptions are used to calculate heat loss:

- a square heat accumulator with constant cross-section, the sides have a length of 4.43m and a height of 20m;

- filling and releasing heat transfer fluid: dry air;

- constant type and volume of energy storage medium;

- The total amount of stored energy is 3.7710 ¹¹ J;

- Duration of the entire cycle: 22 hours, with a total duration of the filling phase of 4 hours, a storage time of 10 hours, and a total duration of the release phase of 8 hours;

-Tc: at the end of the charging phase, the average temperature in the regenerator equal to 550°C;

-Td: at the end of the release phase, the average temperature in the regenerator is equal to 150°C;

- cooling of the housing by water at a temperature of 50°C and a heat transfer coefficient of 100 W/m ² K.

The following formula gives an estimate of the heat loss through the walls of the regenerator after a complete cycle (ie, charging phase and discharging phase):

In that formula:

-T _int (t): average internal temperature of the accumulator in Kelvin;

-T _ext : External temperature of the accumulator, constant, in Kelvin;

-S _int : internal area of the heat accumulator in ^m2 ;

-t _loop : duration of a full loop in seconds;

- R _P : thermal resistance of the protective layer in m ² ·K/W, here equal to the thickness of the protective layer divided by the thermal conductivity of the material of said protective layer;

- R _I : thermal resistance of the insulating layer in m ² ·K/W, here equal to the thickness of the insulating layer divided by the thermal conductivity of the material of said insulating layer;

- R _PI : thermal resistance of the intermediate layer in m ² ·K/W, here equal to the thickness of the intermediate layer divided by the thermal conductivity of the material of said intermediate layer;

-R _h : heat transfer resistance between the housing and the water of the cooling system in m ² ·K/W, here equal to the reciprocal of the heat transfer coefficient at the outer surface of the heat accumulator.

The following formula gives an estimate of the total energy injected into the accumulator, equal to the sum of the energy stored at the end of the charging phase and the heat loss occurring during said phase:

In that formula:

-M: the total weight of the energy storage medium, equal to 785000kg;

-Cp: heat capacity of energy storage medium, equal to 1200J/kg K;

-t _charge : the duration of the charge phase, equal to 14400s.

COMPARATIVE EXAMPLE 1 A regenerator whose side walls comprise an insulating layer with a constant thickness of 420 mm comprising an insulating brick RI30 containing 70% Al ₂ O ₃ sold by Distrisol.

Example 2 according to the invention is a regenerator whose side walls are formed as follows:

The protective layer has a thickness of 200mm and includes the aluminum concrete. The protective layer originates from the assembly of blocks of 1000 x 1000 x 200 ^mm3 , which are shaped by vibratory casting techniques before being placed in the heat accumulator and then dried at 400 °C. The blocks were joined by cement 337 (a cement containing 86% Al ₂ O ₃ sold by Savoie Refractaires).

The protective layer is covered on the outside with an intermediate layer of Insulfrax Paper fiber mat sold by Unifrax with a thickness of 6 mm.

The insulating layer has a thickness of 500mm and consists of Y75LCC self-casting concrete sold by Savoie Refractaires, which is placed by pouring between the accumulator shell and the protective layer, thus acting as a formwork.

Example 3 according to the invention has a regenerator having the same side walls as the regenerator in Example 2, without an intermediate layer of Insulfrax Paper fiber mat.

Example 4 according to the present invention has a heat accumulator whose side walls are formed as follows:

The protective layer was the same as that of Example 2, but had a thickness of 300 mm.

The insulating layer has a thickness of 500 mm and comprises a VK130 dry refractory mixture sold by Saint Gobain Industrie Keramik, which is placed by punching between the regenerator casing and the protective layer.

Example 5 according to the present invention has a heat accumulator whose side walls are formed as follows:

The protective layer was the same as that of Example 2, but comprised Pural T aluminum concrete containing 95% _{Al2O3 .}

The insulating layer had a thickness of 300 mm and consisted of RI30 insulating bricks sold by Distrisol containing 70% Al ₂ O ₃ , assembled before the protective layer and joined by cement 337 .

Embodiment 6 according to the present invention has a heat accumulator whose side walls are formed as follows:

The protective layer had a thickness of 150 mm and comprised AL100, a product sold by Savoie Refractaires containing more than 99% Al ₂ O ₃ . The protective layer results from the assembly of bricks with a cross-section of 400 x 400 mm ² , joined by cement.

The protective layer was covered with an intermediate layer of Zircar APA-2 fiber mat with a thickness of 1.25 mm.

The insulating layer has a thickness of 600mm and consists of Y75LCC self-casting concrete sold by Savoie Refractaires, which is placed by pouring between the accumulator shell and the bricks of the protective layer, thus acting as a formwork.

The results obtained are given in the table below.

In the tables, the protective layer, intermediate layer and insulating layer are denoted by "P", "PI" and "I", respectively.

Table 1

As shown in Table 2 below, under the above operating conditions, the heat accumulator according to the invention is used to minimize heat loss:

Table 2

Of course, the invention is not limited to the described and shown embodiments provided as examples. In particular, combinations of the various embodiments described or shown also lie within the scope of the invention.

The invention is also not limited by the shape or size of the regenerator.

Finally, the energy storage medium can be in contact with a neutral or alkaline environment.

Claims (43)

1. a storage heater; described storage heater comprises the bed (11) of the energy-accumulating medium (12) being placed in chamber (14); described chamber comprise shell (34) and be placed on described shell and described energy-accumulating medium between protective layer (22); described protective layer contacts with described energy-accumulating medium; there is the minimum thickness that is greater than 50mm; and comprise at least in part protective material; with the weight percent meter based on oxide, the composition of described protective material meets:

-Fe ₂o ₃+ Al ₂o ₃+ CaO+TiO ₂+ SiO ₂+ Na ₂o+K ₂o>80%, and

-other oxides: be supplemented to 100%.

2. according to the storage heater described in last claim, wherein, the material of described protective layer or the composition of protective material meet Fe ₂o ₃+ Al ₂o ₃+ SiO ₂>80%.

3. according to the storage heater described in last claim, wherein, the composition of described protective material meets Fe ₂o ₃+ Al ₂o ₃+ SiO ₂>90%.

4. according to the storage heater described in last claim, wherein, the composition of described protective material meets Al ₂o ₃>60%.

5. according to the storage heater described in last claim, wherein, the composition of described protective material meets Al ₂o ₃>85%.

6. according to the storage heater described in last claim, wherein, the composition of described protective material meets Al ₂o ₃>95%.

7. according to the storage heater described in last claim, wherein, the composition of described protective material meets:

-Fe ₂o ₃<20%, and/or

-SiO ₂<10%, and/or

-CaO<2%, and/or

-Na ₂O+K ₂O<0.5％。

8. according to the storage heater described in last claim, wherein, the composition of described protective material meets:

-Fe ₂o ₃<10%, and/or

-SiO ₂<5%, and/or

-CaO<1%, and/or

-Na ₂O+K ₂O<0.3％。

9. according to the storage heater described in last claim, wherein, the composition of described protective material meets:

-Fe ₂o ₃<3%, and/or

-SiO ₂<2%, and/or

-CaO<0.5%, and/or

-Na ₂O+K ₂O<0.2％。

10. storage heater according to claim 1, wherein, with the weight percent meter based on oxide, and adds up to 100%, and the composition of described protective material meets:

-25%<Fe ₂o ₃<70%, and

-5%<Al ₂o ₃<30%, and

-CaO<20%, and

-TiO ₂<25%, and

-3%<SiO ₂<50%, and

-Na ₂o+K ₂o<10%, and

-other oxides <5%.

11. according to the storage heater described in last claim, and wherein, the composition of described protective material meets:

-Fe ₂o ₃>40%, and/or

-Al ₂o ₃<20%, and/or

-CaO>3%, and/or

-TiO ₂>5%, and/or

-SiO ₂>5% and/or SiO ₂<20%, and/or

-Na ₂O+K ₂O<5％。

12. according to storage heater in any one of the preceding claims wherein, and wherein, the most compounds of described protective material is selected from aluminium oxide, bauxite, spinelle MgAl ₂o ₄, mullite, hibonite CaAl ₁₂o ₁₉, aluminium titanates and combination.

13. according to storage heater in any one of the preceding claims wherein, and wherein, described protective material has:

-open porosity lower than 20%, and

-higher than the compressive strength of 50MPa, and

-higher than the heat resisting temperatures of 350 DEG C.

14. according to the storage heater described in last claim, wherein, described protective material has:

-open porosity lower than 10%, and

-higher than the compressive strength of 70MPa, and

-higher than the heat resisting temperatures of 700 DEG C.

15. according to the storage heater described in last claim, wherein, described protective material has:

-open porosity lower than 5%, and

-higher than the compressive strength of 90MPa, and

-higher than the heat resisting temperatures of 900 DEG C.

16. according to storage heater in any one of the preceding claims wherein, and wherein, the minimum thickness of described protective layer is greater than 100mm.

17. according to the storage heater described in last claim, and wherein, the minimum thickness of described protective layer is greater than 150mm.

18. according to storage heater in any one of the preceding claims wherein, wherein, described protective layer is run through by hole (23).

19. according to storage heater in any one of the preceding claims wherein, and wherein, described protective layer is single-piece.

20. according to storage heater in any one of the preceding claims wherein, is included in the insulating barrier (24) extending between described shell (20) and described protective layer (22), and the thermal resistance of described insulating barrier is greater than 0.1m ²k/W.

21. according to the storage heater described in last claim, and wherein, the thermal resistance of described insulating barrier is greater than 0.2m ²k/W.

22. according to the storage heater described in any one in back to back front two claims, and wherein, described insulating barrier comprises insulating materials, and wherein:

The thermal conductivity of-described insulating materials is lower than 2W/mK, and/or

The mechanical compress intensity of-described insulating barrier is greater than 1MPa, and/or

-at 500 DEG C the thermal linear expansion coefficient of measured described insulating materials lower than 0.5%.

23. according to the storage heater described in last claim, wherein:

The thermal conductivity of-described insulating materials is lower than 1.5W/mK, and/or

The mechanical compress intensity of-described insulating barrier is greater than 2MPa, and/or

-at 500 DEG C the thermal linear expansion coefficient of measured described insulating materials lower than 0.4%.

24. according to the storage heater described in last claim, wherein:

The mechanical compress intensity of-described insulating barrier is greater than 5MPa.

25. according to the storage heater described in any one in claim 20 to 24, and wherein, the minimum thickness of described insulating barrier is greater than 150mm.

26. according to the storage heater described in last claim, and wherein, the minimum thickness of described insulating barrier is greater than 300mm.

27. according to the storage heater described in any one in claim 20 to 26, wherein:

The dioxide-containing silica of-described insulating materials is lower than 50%, and/or

The CaO content of-described insulating materials is lower than 10%, and/or

The alumina content of-described insulating materials is higher than 40%.

28. according to the storage heater described in last claim, wherein:

The dioxide-containing silica of-described insulating materials is lower than 10%, and/or

The CaO content of-described insulating materials is lower than 5%, and/or

The alumina content of-described insulating materials is higher than 60%.

29. according to the storage heater described in last claim, wherein:

The dioxide-containing silica of-described insulating materials is lower than 1%, and/or

The CaO content of-described insulating materials is lower than 2%, and/or

The alumina content of-described insulating materials is higher than 80%.

30. according to the storage heater described in any one in claim 20 to 29, and wherein, the main compound of described insulating materials is selected from corundum, spinelle MgAl ₂o ₄, calcined clay, mullite, hibonite CaAl ₁₂o ₁₉, aluminium titanates, bauxite and combination thereof.

31. according to the storage heater described in any one in claim 20 to 30; be included in the intermediate layer (26) of extending between described protective layer (22) and described insulating barrier (24); the maximum ga(u)ge in described intermediate layer is less than 10mm, and described intermediate layer comprises fibrous material.

32. according to the storage heater described in last claim, and wherein, described intermediate layer comprises the aluminium oxide that content is greater than 30%.

33. according to the storage heater described in last claim, and wherein, described intermediate layer comprises the aluminium oxide that content is greater than 70%.

34. according to the storage heater described in last claim, and wherein, described intermediate layer comprises the aluminium oxide that content is greater than 90%.

35. according to the storage heater described in any one in claim 31 to 34, wherein, and the thermal resistance R in described intermediate layer _pIbe greater than 0.05m ²k/W.

36. according to storage heater in any one of the preceding claims wherein, wherein, the weight of described bed is greater than 700 tonnes.

37. 1 kinds of hot chargings are put, and comprising:

The unit (4) of-generation heat energy, and

-according to storage heater in any one of the preceding claims wherein (10), and

-EGR (7), described EGR, during the stage of filling, makes to fill heat-transfer fluid and is circulated to described storage heater from the unit of described generation heat energy, then by described storage heater.

38. 1 kinds for moving the method for putting according to the hot charging described in last claim, wherein, is condensed into the form of acidic liquid from the heat-transfer fluid of the unit (4) of described generation heat energy in described storage heater (10).

39. 1 kinds for moving the method for putting according to the hot charging described in back to back front two claim any one, wherein, from the unit (4) of described generation heat energy and the temperature of described heat-transfer fluid that enters described storage heater lower than 1000 DEG C and higher than 350 DEG C.

40. according to the method for putting for moving hot charging described in last claim, and wherein, described temperature is lower than 800 DEG C and higher than 500 DEG C.

41. 1 kinds for moving the method for putting according to the hot charging described in claim 37 to 40 any one, and wherein, the unit of described generation heat energy comprises compressor.

42. 1 kinds for moving the method for putting according to the hot charging described in claim 36 to 40 any one, described device comprises thermal energy consumption unit (6), described EGR (7) is during the release stage, make to discharge heat-transfer fluid by described storage heater, be then circulated to described thermal energy consumption unit from described storage heater.

43. according to the method for putting for moving hot charging described in last claim, and wherein, described thermal energy consumption unit comprises turbine.