Pressure swing adsorption separation of a gas mixture containing a more readily adsorbed component and a less readily adsorbed component is performed within an apparatus containing an adsorbent bed with cyclically varied geometry, such that the bed volume can be expanded or contracted. Variable volume displacement means at either end of a flow path through the adsorbent bed are operated cyclically to generate flow of a gas mixture along the flow path, in a first direction when the more readily adsorbed component is preferentially adsorbed during the high pressure portion of the cycle while the bed volume is relatively contracted, and in a second reverse direction during the low pressure portion of the cycle while the bed volume is relatively expanded. The apparatus separates the gas mixture and also converts thermal energy by a thermodynamic cycle, such that heat and the more readily adsorbed component are transported in the second direction, while the less readily adsorbed component is transported in the first direction. Adsorbent bed volume is contracted while pressure is rising, and expanded while pressure is reducing, thus minimizing flow along the flow path except when the more readily adsorbed component is maximally or minimally adsorbed, and consequently improving performance of the pressure swing adsorption cycle.

Apparatus and process for pressure swing adsorption separation

@ Pressure swing adsorption gas separations are conducted inside an open loop Stirling cycle apparatus which may operate as an engine, refrigerator or heat pump. Adsorbent surfaces are associated with the thermal regenerators of the Stirling cycle apparatus, so that a preferentially adsorbed gas fraction is concentrated by parametric pumping into a colder end of an engine or into a warmer end of a refrigerator or heat pump, while a less readily adsorbed gas fraction is concentrated into warmer end of an engine or into colder end of a refrigerator or heat pump. Flow control means are provided to introduce the feed gas into the working space of the apparatus and to remove separated product fractions. Feed gases may be chemically reactive within a portion of the working space, with reactant and product species of the reaction separated by the apparatus to drive the reaction off equilibrium. Engine embodiments of the invention may then convert the heat of an exothermic reaction to mechanical power, while heat pump embodiments may supply heat to an endothermic reaction.

Method and apparatus for gas separation and synthesis

Aspects of the disclosure generally provide a heat engine system and a method for regulating a pressure and an amount of a working fluid in a working fluid circuit during a thermodynamic cycle. A mass management system may be employed to regulate the working fluid circulating throughout the working fluid circuit. The mass management systems may have a mass control tank fluidly coupled to the working fluid circuit at one or more strategically-located tie-in points. A heat exchanger coil may be used in conjunction with the mass control tank to regulate the temperature of the fluid within the mass control tank, and thereby determine whether working fluid is either extracted from or injected into the working fluid circuit. Regulating the pressure and amount of working fluid in the working fluid circuit selectively increases or decreases the suction pressure of the pump to increase system efficiency.

Heat Engine and Heat to Electricity Systems and Methods with Working Fluid Mass Management Control

A process and apparatus are disclosed for generating hydrogen gas from a charge of fuel selected from the group consisting of lithium and alloys of lithium and aluminum. The charge of fuel is placed into an enclosed vessel, then heated until it is molten. A reactant consisting of water is introduced into the vessel, as by spraying from a nozzle, for reaction with the charge of fuel resulting in the production of hydrogen gas and heat which are withdrawn from the vessel. Prior to initiation of the process, an inert gas atmosphere, such as argon, may be imparted to the interior of the vessel. A sufficiently large mass flow of the reactant through the nozzle is maintained to assure that there be no diminution of flow resulting from the formation on the nozzle of fuel and chemical compounds of the fuel. Optimum charges of the fuel are application specific and the ranges of the constituents are dependent upon the particular use of the system. The process and apparatus of the invention may be incorporated into a Rankine cycle engine or into a hydrogen oxygen fuel cell system.

System for generating hydrogen

A system for converting thermal energy to work. The system includes a working fluid circuit, and a precooler configured to receive the working fluid. The system also includes a compression stages and intercoolers. At least one of the precooler and the intercoolers is configured to receive a heat transfer medium from a high temperature ambient environment. The system also includes heat exchangers coupled to a source of heat and being configured to receive the working fluid. The system also includes turbines coupled to one or more of the heat exchangers and configured to receive heated working fluid therefrom. The system further includes recuperators fluidly coupled to the turbines, the precooler, the compressor, and at least one of the heat exchangers. The recuperators transfer heat from the working fluid downstream from the turbines, to the working fluid upstream from at least one of the heat exchangers.

Heat engine cycles for high ambient conditions

Improved power cycles for improving the production of power and refrigeration and for conserving thermal energy, utilizing as a common basic characteristic, a hydride-dehydride-hydrogen power cycle in which hydrogen is reversibly combined with a hydride-forming material at a relatively low temperature and pressure, the hydrided material is then heated at constant volume to chemically compress the hydrogen, and finally the material is dehydrided by further heating the material to release hydrogen gas at relatively high pressure and temperature. The pressurized high temperature hydrogen gas as thus developed is used in various ways for producing power and refrigeration, including functioning as a low temperature heat sink for certain auxiliary or ancillary power cycles, prior to recycling the hydrogen gas for reuse in the described hydride-dehydride-hydrogen cycle.

Power cycles based upon cyclical hydriding and dehydriding of a material

A power system comprising a reactor for chemically forming a hydride by reaction with hydrogen at a relatively low pressure and relatively low temperature, means for heating the hydride while retaining it at a constant volume to effect chemical compression of the hydrogen, and a power generating, gas expansion device connected to the reactor for receiving hydrogen under pressure therefrom, and expanding it to derive power therefrom and simultaneously generating refrigeration by expansion of the hydrogen therethrough, and means for regenerating the hydride. A method for deriving power and refrigeration from low-grade thermal energy is also provided and includes the steps of reversibly combining hydrogen with a hydride-forming material at a relatively low temperature and pressure, heating the hydride at constant volume, reversibly dehydriding the material to develop hydrogen at relatively higher pressure and temperature, and expanding the hydrogen through a turbine or other power producing device, and cooling the spent hydride.

Roger J. Schoeppel

Papers

Power cycles based upon cyclical hydriding and dehydriding of a material

Hydride-dehydride power system and methods

Power cycles based upon cyclical hydriding and dehydriding of material of a material