A system and a method for processing air prior to separating components of the air are disclosed. The system comprises an air cooler, one or more compression stages operated in series, and one or more intercoolers installed between two adjacent compression stages. A blowdown storage tank is configured to collect water blowdown from one or more intercoolers and provide cooling medium to the air cooler. Atmospheric air is first sprayed by the water blowdown in the air cooler to form a cooled air stream. The cooled air stream is subsequently compressed in the one or more compression stages and cooled by the intercoolers between two adjacent compression stages. The water blowdown from one or more of the intercoolers is collected and recycled as the cooling medium to cool the atmospheric air before it enters the first compression stage.

In a method for compressing a gas that is to be separated in a low-temperature CO.sub.2 separation unit using at least one partial condensation step and/or at least one distillation step, the gas that is to be separated has a variable composition and/or variable flow rate, the gas that is to be separated is compressed in a compressor to produce a compressed gas and the inlet pressure of the gas that is to be separated, entering the compressor, is modified according to the CO.sub.2 content and/or the flow rate of the gas that is to be separated so as to reduce the variations in volumetric flow rate of the gas that is to be separated entering the compressor.

A process for compressing a gaseous fluid comprising a step (a) of injecting refrigerant during which a refrigerant substance is sprayed into the gaseous fluid to be compressed, and also a compression step (b), during which the passage of said gaseous fluid loaded with refrigerant substance is forced through said compressor in order to compress said gaseous fluid, the mass flow rate (Q3) of the refrigerant substance injected into the gaseous fluid represents between 1% and 5% of the mass flow rate of the gaseous fluid to be compressed, and the refrigerant substance is sprayed in the form of particles having a maximum dimension of less than or equal to 25 pm, and preferably less than or equal to 10 pm.

A cryogenic method for capturing carbon dioxide in the gaseous emissions produced from the fossil-energy combustion of solid, liquid, or gaseous fossil fuels in a power generation installation employing an OxyFuel mode of combustion. The method includes: producing essentially pure carbon dioxide under elevated pressure and at near ambient temperatures in a Carbon-Dioxide Capture Component from the carbon-dioxide content of at least a part of the gaseous emissions produced from fossil-energy fueled combustion in the Oxyfuel mode of combustion; separating atmospheric air in an Air Separation Component into a stream of liquid nitrogen and a stream of high-purity oxygen; supplying low temperature, compressed purified air to a cryogenic air separation unit (cold box) within the Air Separation Component; collecting low temperature thermal energy from coolers employed within the Carbon-Dioxide Capture Component and the Air Separation Component; and converting the collected thermal energy to electricity within a Thermal-Energy Conversion Component.

A process for compressing a gaseous fluid comprising a step (a) of injecting refrigerant during which a refrigerant substance is sprayed into the gaseous fluid to be compressed, and also a compression step (b), during which the passage of said gaseous fluid loaded with refrigerant substance is forced through said compressor in order to compress said gaseous fluid, the mass flow rate (Q3) of the refrigerant substance injected into the gaseous fluid represents between 1% and 5% of the mass flow rate of the gaseous fluid to be compressed, and the refrigerant substance is sprayed in the form of particles having a maximum dimension of less than or equal to 25 m, and preferably less than or equal to 10 m.

An apparatus for compressing air and producing a carbon dioxide-rich fluid includes an air compressor, an element for bringing the air bound for the air compressor into contact with water to produce humidified air and cooled water, a pipe for sending the humidified compressed air from the air compressor to an installation producing a carbon dioxide-rich gas, a carbon dioxide-rich gas compressor for compressing the carbon dioxide-rich gas, at least one heat exchanger upstream and/or downstream the carbon dioxide-rich gas compressor and pipes for conveying into the heat exchanger water cooled in the contact element and the carbon dioxide-rich gas.

A distillation column system and a plant are for production of oxygen by cryogenic fractionation of air. The distillation column system has a high-pressure column and a low-pressure column, a main condenser, and an argon column with an argon column top condenser. The low-pressure column comprises an upper mass transfer region, a lower mass transfer region and a middle mass transfer region. The argon column top condenser is arranged within the low-pressure column between the upper and middle mass transfer regions and is configured as a forced-flow evaporator.

An apparatus for separating air by cryogenic distillation comprises N air compressors (C1, C2, C3) connected so as to receive air at ambient pressure and designed to produce air at a first pressure above 12 bar absolute, N being at least 3, each of the compressors being driven by a single asynchronous motor (M1, M2, M3), the total power of the compressors being at least 10 MW.