Combined cycle natural gas processing system that does not discharge carbon dioxide to the atmosphere. The system is provided with an acid gas removal unit that separates carbon dioxide contained in natural gas, and includes a natural gas processing plant that produces liquefied natural gas, and a carbon dioxide cycle. High energy held by a high-temperature and high-pressure carbon dioxide fluid of the carbon dioxide cycle is converted into electrical energy or mechanical energy and supplied to a power consumption device and an energy consumption device provided in the natural gas processing plant. The carbon dioxide fluid extracted from the carbon dioxide cycle and a carbon dioxide separation stream separated by the acid gas removal unit are supplied to a carbon dioxide reception facility capable of receiving carbon dioxide, so that the carbon dioxide generated with production of the liquefied natural gas is not released to the atmosphere.

The present invention relates to a method for production of H.sub.2 from natural gas, solid fossil fuels or biomass. The method comprises the following steps: reacting natural gas in a reformer or reacting solid fossil fuels or biomass in a gasifier to form syngas, reacting the syngas to form a shifted gas mixture, comprising H.sub.2 and CO.sub.2, in a water-gas-shift (WGS) section, separating the shifted gas mixture into a H.sub.2 gas and a H.sub.2 depleted tail gas mixture or retentate gas mixture in a H.sub.2 separation unit, separating the H.sub.2-depleted tail gas mixture or retentate gas mixture into a CO.sub.2 liquid and a CO.sub.2-depleted tail gas mixture in a CO.sub.2 capture and liquefaction unit, and recycling the CO.sub.2-depleted tail gas mixture from the CO.sub.2 capture and liquefaction unit without recompression to the WGS section and to the reformer or the gasifier. The CO.sub.2-depleted tail gas mixture is at a pressure in the range from 25 to 120 bar when recycled to the WGS section and to the reformer or the gasifier.

A CO.sub.2 energy storage system includes a storage tank that stores a CO.sub.2 slurry, including dry ice and liquid CO.sub.2, at CO.sub.2 triple point temperature and pressure conditions. The storage system also includes a first pump coupled in flow communication with the storage tank. The first pump is configured to receive the CO.sub.2 slurry from the storage tank and to increase a pressure of the CO.sub.2 slurry to a pressure above the CO.sub.2 triple point pressure. The energy storage system further includes a contactor coupled in flow communication with the first pump. The contactor is configured to receive the high pressure CO.sub.2 slurry from the pump and to receive a first flow of gaseous CO.sub.2 at a pressure above the CO.sub.2 triple point pressure. The gaseous CO.sub.2 is contacted and then condensed by the melting dry ice in the slurry to generate liquid CO.sub.2.

The invention provides a cryogenic pump reservoir (100), for a cryogenic liquid to be fed to a pump (208), with an interior reservoir space (103) extending between a reservoir bottom (101) and a reservoir top (102) and comprising a liquid feeding region (104), which is positioned at a first distance from the reservoir bottom (101) in the direction of the reservoir top (102), and a liquid removing region (105), which is positioned at a second distance from the reservoir bottom (101) in the direction of the reservoir top (102), the second distance being greater than the first distance. It is provided that in the liquid feeding region (104) there is formed a liquid feeding opening (106), that the interior reservoir space (103) is at least partially divided in the liquid feeding region (104) by means of a dividing wall (106), which is arranged in such a way that one of its surfaces (107) is aligned in the direction of the liquid feeding opening (106. A corresponding rectification system (200) and a process for low-temperature rectification are likewise the subject of the present invention.

A device for separating a gas mixture containing at least 35 mol % carbon dioxide and also at least one gas lighter than carbon dioxide, comprising a first phase separator configured to receive a first partially condensed flow from an exchange line; a first phase separator configured to separate the gas phase from the liquid phase; a cooling means configured to receive the gas phase from the first phase separator and cool said gas phase to form a second partially condensed flow. The resulting liquid phase is then sent to a first valve and is expanded to a lower pressure that is at most 300 mbar lower in order to form a first expanded liquid, which is then mixed with a second liquid originating from the second phase separator in a mixing means that is located upstream of a third valve.

In a method for separating a flow containing at least 95 mol % of carbon dioxide and at least one impurity lighter than carbon dioxide by distillation, the flow is cooled to a first intermediate temperature between those of the cold end and the hot end of a heat exchange means in order to form a liquid flow at a first temperature and a first pressure and it is split into at least two to form a first fraction and a second fraction, the first fraction is expanded to the pressure of a distillation column, referred to as second pressure, which is lower than the first pressure, and it is sent to an intermediate level of the distillation column, the second fraction is cooled in the heat exchange means to the cold end thereof, it is expanded to the pressure of the distillation column and is sent to a level of the distillation column above the point of arrival of the first fraction, a liquid flow containing at least 99 mol % of carbon dioxide is withdrawn from the bottom of the column, and a fraction of the liquid flow is pressurized in a pump and sent to the top of the column.

The present disclosure relates to systems and methods useful for providing one or more chemical compounds in a substantially pure form. In particular, the systems and methods can be configured for separation of carbon dioxide from a process stream, such as a process stream in a hydrogen production system. As such, the present disclosure can provide systems and method for production of hydrogen and/or carbon dioxide.

In a purification method, a carbon dioxide-rich gas is cooled in a first brazed aluminum plate-fin heat exchanger, the cooled gas or at least one fluid derived from the cooled gas is sent to a purification step comprising a distillation step, the purification step produces a carbon dioxide-rich liquid which is cooled, then expanded, then sent to a second heat exchanger where it is heated by means of a fluid of the method, the exchanger carrying out an indirect heat exchange only between the carbon dioxide-rich liquid and the fluid of the method, the carbon dioxide-rich liquid at least partially vaporizes in the second exchanger and the vaporized gas formed heats up again in the first exchanger to form a carbon dioxide-rich gas.

In a method for separating a mixture containing carbon dioxide, the mixture is cooled in a heat exchanger and partially condensed and a first liquid is separated from the mixture in a first system operating at low temperature comprising at least one first phase separator and a gas from the first system is treated in a membrane system to produce a permeate and a non-permeate, the gas from the first system being divided into two portions, a first portion being sent to the membrane system without being heated and a second portion being heated to at least an intermediate temperature of the heat exchanger and then sent to the membrane system without being cooled.

In a process for separating at least one heavy impurity such as hydrogen sulfide from crude carbon dioxide comprising significant quantities of at least one light impurity such as non-condensable gases, involving at least one heat pump cycle using carbon dioxide-containing fluid from the process as the working fluid, the light impurity is removed from the crude carbon dioxide and carbon dioxide is subsequently recovered from the removed light impurity, thereby improving overall carbon dioxide recovery and efficiency in terms of energy consumption.