Abstract: A method is disclosed for prevention or stoppage of sulfidation or sulfuric corrosion of metal surfaces in contact with fluids including sulfiding compounds, where the method involves the addition of a compound to the fluid, where the additive has a higher affinity for metal surfaces than sulfur. The additive are group 15 of the periodic table of elements, fluorine-containing compounds, or mixtures or combinations thereof and are added in small quantities generally between about 0.001 ppm and about 20 ppm based on the amount of group 15 element or fluorine in the compound used. A protected metal surface is also disclosed which is coated with a protective coating comprising a group 15 element or fluorine and/or sulfur.

Abstract: A new thermodynamic cycle is disclosed for converting energy from a low temperature stream, external source into useable energy using a working fluid comprising of a mixture of a low boiling component and a higher boiling component and including a higher pressure circuit and a lower pressure circuit. The cycle is designed to improve the efficiency of the energy extraction process by recirculating a portion of a liquid stream prior to further cooling. The new thermodynamic processes and systems for accomplishing these improved efficiencies are especially well-suited for streams from low-temperature geothermal sources.

Abstract: A new thermodynamic cycle is disclosed for converting energy from a low temperature stream, external source into useable energy using a working fluid comprising of a mixture of a low boiling component and a higher boiling component and including a higher pressure circuit and a lower pressure circuit. The cycle is designed to improve the efficiency of the energy extraction process by recirculating a portion of a liquid stream prior to further cooling. The new thermodynamic processes and systems for accomplishing these improved efficiencies are especially well-suited for streams from low-temperature geothermal sources.

Abstract: A new thermodynamic cycle is disclosed for converting energy from a low temperature stream, external source into useable energy using a working fluid comprising of a mixture of a low boiling component and a higher boiling component and including a higher pressure circuit and a lower pressure circuit. The cycle is designed to improve the efficiency of the energy extraction process by recirculating a portion of a liquid stream prior to further cooling. The new thermodynamic processes and systems for accomplishing these improved efficiencies are especially well-suited for streams from low-temperature geothermal sources.

Abstract: a new thermodynamic cycle is disclosed for converting energy from a low temperature stream from an external source into useable energy using a working fluid comprising of a mixture of a low boiling component and a higher boiling component and including a higher pressure circuit and a lower pressure circuit. The cycle is designed to improve the efficiency of the energy extraction process by mixing the liquid stream from the high pressure circuit with the spent low pressure circuit stream forming a lean system that can be condensed at a low pressure. The new thermodynamic process and the system for accomplishing it are especially well-suited for streams from low-temperature geothermal sources.

Abstract: A new thermodynamic cycle is disclosed for converting energy from a low temperature stream from an external source into useable energy using a working fluid comprising of a mixture of a low boiling component and a high boiling component. The cycle is designed to improve the efficiency of the energy extraction process by mixing into an intermediate liquid stream an enriched liquid stream from which the energy from the external source stream is extracted in a vaporization step and converted to energy in an expansion step. The new thermodynamic process and the system for accomplishing it are especially well-suited for streams from low-temperature geothermal sources.

Abstract: A new system and method for extracting useful work from geothermal streams is disclosed. The systems and methods of this invention can achieve an estimated 20 to 30% improvement in output efficiency. The increased efficiency is derived from a secondary energy conversion step involving a low pressure vapor stream of variable composition and a low pressure turbine, which expands the vapor stream to produce the improved efficiency.

Abstract: A method is disclosed for prevention nitridation or carburization of metal surfaces in contact with a fluid including nitriding agents or carburizing agents where the method involves adding to the fluid an effective amount a sulfur-containing compound and a phosphorus compound, where the amount of phosphorus-containing compound is less than the amount of sulfur-containing compound. The simultaneous addition of both a sulfur compound and a phosphorus compound prevents nitridation and/or carburization and sulfidation of the metal surfaces in contact with fluids containing nitriding and/or carburizing agents significantly increasing the metal's lifetime.

Abstract: A method is disclosed for prevention nitridation or carburization of metal surfaces in contact with a fluid including nitriding agents or carburizing agents where the method involves adding to the fluid an effective amount a sulfur-containing compound and a phosphorus compound, where the amount of phosphorus-containing compound is less than the amount of sulfur-containing compound. The simultaneous addition of both a sulfur compound and a phosphorus compound prevents nitridation and/or carburization and sulfidation of the metal surfaces in contact with fluids containing nitriding and/or carburizing agents significantly increasing the metal's lifetime.

Abstract: A method is disclosed for prevention or stoppage of sulfidation or sulfuric corrosion of metal surfaces in contact with fluids including sulfiding compounds, where the method involves the addition of a compound to the fluid, where the additive has a higher affinity for metal surfaces than sulfur. The additive are group 15 of the periodic table of elements, fluorine-containing compounds, or mixtures or combinations thereof and are added in small quantities generally between about 0.001 ppm and about 20 ppm based on the amount of group 15 element or fluorine in the compound used. A protected metal surface is also disclosed which is coated with a protective coating comprising a group 15 element or fluorine and/or sulfur.

Abstract: A method and apparatus for implementing a thermodynamic cycle. A heated gaseous working stream including a low boiling point component and a higher boiling point component is separated, and the low boiling point component is expanded to transform the energy of the stream into useable form and to provide an expanded relatively rich stream. This expanded rich stream is then split into two streams, one of which is expanded further to obtain further energy, resulting in a spent stream, the other of which is extracted. The lean unexpanded stream and the spent rich stream are then combined in a regenerating subsystem with the extracted stream to reproduce the working stream, which is then efficiently heated in a heater to provide the heated gaseous working stream that is separated.

Abstract: A method of implementing a thermodynamic cycle by expanding a gaseous working stream to transform its energy into a useful form and produce an expanded gaseous stream, removing from the expanded gaseous stream an extracted stream, absorbing the extracted stream into a lean stream having a higher content of higher-boiling component than is contained in the extracted stream to form a combined extracted/lean stream, at least partially condensing the combined extracted/lean stream, combining at least part of the combined extracted/lean stream in condensed form with an oncoming working stream including a rich stream having a lower content of higher-boiling component than is contained in the extracted stream to provide a combined working stream, and heating the combined working stream with external heat to provide the gaseous working stream.

Abstract: Converting heat in a primary fluid (e.g., steam) to useful energy by multistage expansion of the primary fluid, heating of a multicomponent working fluid in a separate closed loop using heat of the primary fluid, and expansion of the multicomponent working fluid. The primary fluid in a vapor state is expanded in a first stage expander to obtain useful energy and to produce a partially expanded primary fluid. The partially expanded primary fluid stream is then separated into liquid and vapor components and split into a vapor stream (which is expanded in a second stage expander) and a further primary stream (which used to heat the multicomponent working fluid).

Abstract: A method and apparatus for implementing a thermodynamic cycle. A heated gaseous working stream including a low boiling point component and a higher boiling point component is expanded to transform the energy of the stream into useable form and to provide an expanded working stream. The expanded working stream is then split into two streams, one of which is expanded further to obtain further energy, resulting in a spent stream, the other of which is extracted. The spent stream is fed into a distillation/condensation subsystem, which converts the spent stream into a lean stream that is lean with respect to the low boiling point component and a rich stream that is enriched with respect to the low boiling point component. The lean stream and the rich stream are then combined in a regenerating subsystem with the portion of the expanded stream that was extracted to provide the working stream, which is then efficiently heated in a heater to provide the heated gaseous working stream that is expanded.

Abstract: Apparatus and method for supplying heat to an externally fired power system by using a multistage system having two or more combustion zones. Each combustion zone has an associated heat exchanger that conveys a respective working fluid stream from the externally fired power system. Each combustion zone receives a portion of the total amount of combustion fuel, and the amount of fuel and air supplied to each combustion zone is adjusted to control the temperature to a predetermined value.

Abstract: Method and apparatus for implementing a thermodynamic cycle in which a gaseous working fluid is expanded to transform its energy into useable form, thereby generating a spent stream which is then condensed to produce a condensed stream. From the condensed stream the following streams are generated: a first stream having a higher percentage of a low boiling component than is included in the condensed stream, a second stream having a lower percentage of a low boiling component than is included in the condensed stream, and a third stream having the same percentage of a low boiling component as is included in the condensed stream. The first, second, and third streams are subjected to multiple distillation operations to generate a liquid working fluid which is then evaporated to generate the gaseous working fluid.

Abstract: A multi-stage combustion apparatus and method for use with externally fired power plants that allows the temperature of the heat released at any stage to be matched to the thermal characteristics of the working fluid from the power plant.

Abstract: A method and apparatus for implementing a thermodynamic cycle that includes: (a) expanding a gaseous working stream, transforming its energy into usable form and producing a spent working stream; (b) heating a multicomponent oncoming liquid working stream by partially condensing the spent working stream; and (c) evaporating the heated working stream to form the gaseous working stream using heat produced by a combination of cooling geothermal liquid and condensing geothermal steam.

Abstract: A multi-flow tubular heat exchanger is enclosed. The heat exchanger includes a shell that encloses one or more cooling stream tubes, one or more heating stream tubes, and a heat transfer fluid.

Abstract: A method and apparatus for converting thermal energy into electric power. A high pressure gaseous working stream is expanded, producing a spent stream. The spent stream is condensed, producing a condensed stream. The condensed stream forms first and second partially evaporated streams, which in turn form first and second vapor streams and first and second liquid streams. A rich stream is generated from the first vapor stream. A lean stream is generated from combining the second vapor stream with a mixing stream. The resulting rich and lean streams are passed through a boiler where they are evaporated. After exiting the boiler, the evaporated rich stream is combined with the evaporated lean stream generating the high pressure gaseous working stream, completing the cycle.