A sintered material exhibiting the following chemical composition, as percentages by weight: iron oxide(s), expressed in the Fe.sub.2O.sub.3 form, ≥85%, CaO: 0.1%-6%, SiO.sub.2: 0.1%-6%, 0.05% ≤TiO.sub.2, 0≤Al.sub.2O.sub.3, TiO.sub.2+Al.sub.2O.sub.3≤3%, and constituents other than iron oxides, CaO, SiO.sub.2, TiO.sub.2 and Al.sub.2O.sub.3: ≤5%. The CaO/SiO.sub.2 ratio by weight is between 0.2 and 7. The TiO.sub.2/CaO ratio by weight is between 0.2 and 1.5.

Heat exchanger presenting a first gas flow path containing a heat-regenerative packing and a separate second gas flow path containing a heat-conductive packing and use of same for heating a gas to be heated by means of heat recovered from a hot gas in a two-phase alternating heat-recovery process.

Barocaloric heat transfer systems and related methods are generally described. In some embodiments, a heat transfer system may include a barocaloric material which may generate heat upon compression and may cool down upon decompression. The barocaloric material may be pressurized using high pressure and low pressure fluids, which may, in some embodiments, also transfer heat to/from the barocaloric material. The heat transfer system may also include a hot heat exchanger to dissipate heat from the heat transfer system to a first environment and a cold heat exchanger to absorb heat from a second environment, effectively cooling the second environment. In some embodiments, the barocaloric material may be in particulate form.

The invention relates to a method and to a device for performing cyclical energy storage for a process region in a cyclical operation using an energy storage medium having a hot side and a cold side, the method comprising the following method steps, which are repeated in a cycle time. The energy storage medium is heated on the hot side by means of a hot medium in order to initiate internal thermal conduction in the energy storage medium from the hot side to the cold side. The temperature on the cold side of the energy storage medium is continuously captured by means of a temperature sensor and is compared with a preset limit temperature. After the limit temperature has been reached, a cold medium is fed to the cold side of the energy storage medium and the stored energy is discharged beginning from the cold side toward the hot side of the energy storage medium. At the start of a new energy storage cycle, the energy storage medium is heated on the hot side again.

Provided is an energy storage device, including: a first heat exchanger configured to exchange heat between gas and solid particles; a gas supplier configured to supply gas to the first heat exchanger; a heater configured to consume power to heat any one of or both of gas fed from the gas supplier to be supplied to the first heat exchanger and gas present in the first heat exchanger; a solid-gas separator configured to separate gas and solid in a solid-gas mixture discharged from the first heat exchanger; a high-temperature tank and a low-temperature tank each configured to store the solid particles separated by the solid-gas separator; a first heat utilization device configured to use thermal energy of the gas separated by the solid-gas separator; a high-temperature particle supplier configured to supply the solid particles stored in the high-temperature tank to the first heat exchanger; and a low-temperature particle supplier configured to supply the solid particles stored in the low-temperature tank to the first heat exchanger.

Methods and devices for long-duration electricity storage using low-cost thermal energy storage and high-efficiency power cycle, are disclosed. In some embodiments it has the potential for superior long-duration, low-cost energy storage.

A heat recovery apparatus, system and method of using the same. The heat recovery apparatus includes a particulate inlet, a particulate distributor in fluid communication with the particulate inlet, a cavity in fluid communication with the particulate distributor, a plurality of pipes contained within the cavity and configured for transmission of a heat transfer fluid therethrough, and a particulate outlet in fluid communication with the cavity.

A heat storage reservoir comprising: at least one input inlet for introduction of gaseous heat transfer fluid, or for introduction of superheated liquid heat transfer fluid, into the heat storage reservoir, and at least one liquid recovery system for recovery of liquid heat transfer fluid from the heat storage reservoir; and/or at least one gas outlet for recovery of gaseous heat transfer fluid from the heat storage reservoir, and at least one output inlet for introduction of liquid heat transfer fluid into the heat storage reservoir; and further comprising a volume of solid granular material, to which volume heat is transferred by means of a phase change from gas to liquid of a heat transfer fluid on contact of the heat transfer fluid with the solid granular material, and/or from which volume heat is transferred by means of a phase change from liquid to gas of a heat transfer fluid on contact of the heat transfer fluid with the solid granular material, which volume is in fluid connection with the at least one input inlet and the at least one liquid recovery system, and/or the at least one gas outlet and the at least one output inlet, and a pressure reduction system in fluid connection with the volume of solid granular material, characterized in that the pressure reduction system is arranged to reduce the gas pressure contribution arising from non-condensable species only.

Heat exchanger presenting a first gas flow path containing a heat-regenerative packing and a separate second gas flow path containing a heat-conductive packing and use of same for heating a gas to be heated by means of heat recovered from a hot gas in a two-phase alternating heat-recovery process.

A heat sink vessel is disclosed herein. The heat sink vessel includes a body and one or more heating media. The body defines an inner volume. The body includes an upper portion, a middle portion, and a lower portion. The upper portion has a conical entrance for incoming flow of fluid. The middle portion has a first side and a second side. The middle portion interfaces with the upper portion of the first side. The lower portion interfaces with the middle portion on the second side. The lower portion includes an inverted perforated conical liner and a perforated plate. The inverted perforated conical liner and the perforated plate control the flow of fluid exiting the vessel. The one or more heating media is disposed in the inner volume. The one or more heating media is configured to store heat during processing.