An energy storage apparatus and method based on carbon dioxide gas-liquid phase change. The energy storage apparatus comprises a gas storage reservoir; a liquid storage tank; an energy storage assembly, provided between the gas storage reservoir and the liquid storage tank, wherein the energy storage assembly comprises a condenser and at least two compression energy storage parts, the compression energy storage parts each comprise a compressor and an energy storage heat exchanger; an energy release assembly, provided between the gas storage reservoir and the liquid storage tank, wherein the energy release assembly comprises an evaporator, an energy release cooler, and at least one expansion energy release part, the expansion energy release part comprises an expander and an energy release heat exchanger; and a heat exchange assembly, comprising a cool storage tank, a heat storage tank, and a heat recovery heat exchanger.

The present disclosure provides methods whereby products can be prepared in a manner that adds value to the products beyond the market value of such products, and the present disclosure further provides methods for optimizing production of products toward processes that yield a positive net result. The methods for preparing a product can utilize a synthesized oxide compound and, depending upon the order of combination, can modify the synthesized oxide compound by combination with both of carbon dioxide and a secondary component.

Systems and methods for converting energy are provided. In one aspect, the system includes a closed cycle engine defining a cold side. The system also includes a bottoming-cycle loop. A pump is operable to move a working fluid along the bottoming-cycle loop. A cold side heat exchanger is positioned along the bottoming-cycle loop in a heat exchange relationship with the cold side of the closed cycle engine. A constant density heat exchanger is positioned along the bottoming-cycle loop downstream of the cold side heat exchanger and upstream of an expansion device. The constant density heat exchanger is operable to hold a volume of the working fluid flowing therethrough at constant density while increasing, via a heat source, the temperature and pressure of the working fluid. The expansion device receives the working fluid at elevated temperature and pressure and extracts thermal energy from the working fluid to produce work.

The present disclosure is directed to systems and methods generating power using supercritical CO.sub.2 in a Brayton cycle that incorporates a double-wall turboexpander that includes an inner chamber housing the turbine and an outer chamber that includes a thermal attenuator that reduces the outer chamber wall temperature of the turboexpander. An inner chamber wall separates the inner chamber and the outer chamber within the double-wall turboexpander. In supercritical CO.sub.2 applications, the double-wall turboexpander operates at elevated temperatures and elevated pressures. By maintaining the thermal attenuator the outer chamber at an elevated pressure, the differential pressure across the inner chamber wall is reduced, requiring less high-temperature alloy material in the construction of the double-wall turboexpander when compared to a conventional turboexpander. By reducing the operating temperature of the outer chamber wall, a less costly lower-temperature alloy may be used to provide structural strength to the double-wall turboexpander.

A natural gas power generation process with zero carbon emission is described. The process includes pressurizing air and introducing the pressurized air into an air separation facility to obtain liquid oxygen and liquid nitrogen. The liquid oxygen is used for gasification and power generation The liquid nitrogen is applied as a coolant of flue gas, and then for gasification and power generation.

An assembly with a piston reciprocated with the aid of a floating head in fluid communication with the piston. The assembly may utilize a floating head that is shifted in position to promote reciprocation of the piston through the aid of pressure supplied to the floating head from a pressure volume regulator. Alternatively, the floating head may be in fluid communication with the piston at one side of the head and isolated at the other side. In this manner changing volume and pressure at this other side of the head during reciprocation may ultimately lead to floating head movement toward the piston, thereby promoting the continued reciprocation. Additional efficiencies may also be realized through unique hydraulic layouts for both operating and working fluid circulations.

The present disclosure relates to systems and methods that are useful in control of one or more aspects of a power production plant. More particularly, the disclosure relates to power production plants, methods of starting power production plants, and methods of generating power with a power production plant wherein one or more control paths are utilized for automated control of at least one action. The present disclosure more particularly relates to power production plants, control systems for power production plants, and methods for startup of a power production plant.

A power generation system burns a fuel in a gas in a combustion chamber, producing one or more combustion products and heating a working fluid, preferably supercritical CO.sub.2, that is chemically the same as a combustion product. The working fluid is mixed with the combustion products to form a combustion output mixture which is used in a turbine to drive a shaft of the turbine connected with a generator, producing electricity. The turbine outputs an exhaust that goes to a working fluid recycling system that connects the turbine outlet with the combustion chamber. The fluid recycling system has a radial compressor that receives and pressurizes the exhaust mixture and sends it to a chamber that has a bleed outlet and a recycling outlet. The recycling outlet transmits a recycled portion of the exhaust mixture to the combustion chamber, and the bleed outlet carries an excess portion of the exhaust mixture that is not to be recycled to an extraction system that removes it from the power generation system for use in other applications.

A pericritical fluid system for a thermal management system associated with a turbine engine may include one or more sensors configured to generate sensor outputs corresponding to one or more phase properties of a pericritical fluid flowing through a cooling circuit of the thermal management system, and a controller configured to generate control commands configured to control one or more controllable components of the thermal management system based at least in part on the sensor outputs. The one or more sensors may include one or more phase detection sensors, such as an acoustic sensor.

Techniques for cogeneration of heat and power are disclosed. A cogeneration system includes: a conduit loop configured to carry a working fluid using a Rankine cycle; a valve system disposed along the conduit loop, including valves configured to manage flow of the working fluid through a chamber; a backflow vapor line disposed along the conduit loop, configured to direct working fluid in a gaseous state to the chamber, such that the working fluid in the gaseous state displaces working fluid in a liquid state in the chamber and the working fluid in the liquid state advances through the conduit loop without requiring a mechanical pump; and a heat exchanger disposed along the conduit loop, configured to extract heat from the working fluid and direct the heat to a practical use.