A process for separating carbon dioxide from a waste gas of a fluid catalytic cracking installation including converting at least a portion of the carbon monoxide of the waste gas into carbon dioxide to form a flow enriched in carbon dioxide, separating at least a portion of the flow enriched in carbon dioxide to form a gas enriched in carbon dioxide and depleted in nitrogen and a gas rich in nitrogen and depleted in carbon dioxide, and at least a portion of the gas enriched in carbon dioxide and depleted in nitrogen is separated by way of separation at a temperature of less than 0° C. to form a fluid rich in carbon dioxide and a fluid depleted in carbon dioxide and sending a gas containing at least 90% oxygen to combustion.

Disclosed is a BOG reliquefaction system. The BOG reliquefaction system includes: a compressor compressing BOG; a heat exchanger cooling the BOG compressed by the compressor through heat exchange using BOG not compressed by the compressor as a refrigerant; a pressure reducer disposed downstream of the heat exchanger and reducing a pressure of fluid cooled by the heat exchanger; and a second oil filter disposed downstream of the pressure reducer, wherein the compressor includes at least one oil-lubrication type cylinder and the second oil filter is a cryogenic oil filter.

A method for generating liquefied gas is provided. The method includes receiving air, refining the air to create refined air, performing liquefaction on refined air to form liquefied gas, and transferring at least one constituent liquefied gas of the liquefied gas to a storage tank in a lighter than air aircraft. The constituent liquefied gas(es) is configured to serve as an energy source for the lighter than air aircraft. The method may include distilling the liquefied gas to obtain liquid nitrogen and one or more other constituent gases. The liquid nitrogen may be configured to store at least 250 kilojoule per liter of energy. Additionally, the air may be refined to create refined air by compressing the air, separating water from the air, scrubbing carbon dioxide from the air, and/or filtering dust from the air. The method may be carbon-neutral or carbon-negative.

In a process for separating carbon dioxide from a waste gas (3) of a fluid bed catalytic cracking installation (1) containing carbon dioxide, nitrogen and possibly carbon monoxide, the waste gas (3) is separated by adsorption to form a gas enriched in carbon dioxide and depleted in nitrogen (29) and a gas rich in nitrogen and depleted in carbon dioxide (31), and at least a portion of the gas enriched in carbon dioxide and depleted in nitrogen is separated in a separation device (30) by way of separation at a temperature of less than 0° C. by partial condensation and/or by distillation to form a fluid rich in carbon dioxide (35) and a fluid depleted in carbon dioxide (37).

Disclosed is a BOG reliquefaction system. The BOG reliquefaction system includes: a compressor compressing BOG; a heat exchanger cooling the BOG compressed by the compressor through heat exchange using BOG discharged from a storage tank as a refrigerant; a bypass line through which the BOG is supplied to the compressor after bypassing the heat exchanger; a second valve disposed on a second supply line through which the BOG used as the refrigerant in the heat exchanger is supplied to the compressor, the second valve regulating a flow rate of fluid and opening/closing of the second supply line; and a pressure reducer disposed downstream of the heat exchanger and reducing a pressure of fluid cooled by the heat exchanger, wherein the compressor includes at least one oil-lubrication type cylinder and the bypass line is joined to the second supply line downstream of the second valve.

An apparatus for producing a purified, pressurized liquid carbon dioxide stream includes a distillation column (B) having packing (C) therein and a sump (D) below the packing, the distillation column in fluid communication with the liquid carbon dioxide supply tank for receiving the liquid carbon dioxide stream and the packing stripping volatile impurities from the liquid carbon dioxide stream; a heater (E) in contact with the liquid carbon dioxide stream in the sump (D) for vaporizing the liquid carbon dioxide stream in the sump; a vent in the distillation column (B) from which a first vaporized portion (G) of carbon dioxide vapor in the sump (D) is withdrawn from the distillation column: and a conduit (I) in fluid communication with the sump (D) and from which a second vaporized portion (H) of the carbon dioxide vapor in the sump is withdrawn into the conduit (I) to be introduced into the carbon dioxide vapor feed stream.

The invention concerns a heat exchanger having an exchange body having first passages for the flow of a first fluid and second passages for the flow of a second fluid exchanging heat with the first fluid, a first inlet manifold for introducing the first fluid into the first passages, a first outlet manifold for discharging the first fluid from the first passages). The heat exchanger also includes an inlet filter arranged facing the inlet surface of the exchange body, and/or an outlet filter arranged facing the outlet surface of the exchange body, the inlet filter and/or the outlet filter having a sheet metallic material selected from a metal gauze, a non-woven fabric of metallic fibres, a sintered metallic powder or sintered metallic fibres.

A liquefier device which may be a retrofit to an air separation plant or utilized as part of a new design. The flow needed for the liquefier comes from an air separation plant running in a maxim oxygen state, in a stable mode. The three gas flows are low pressure oxygen, low pressure nitrogen, and higher pressure nitrogen. All of the flows are found on the side of the main heat exchanger with a temperature of about 37 degrees Fahrenheit. All of the gasses put into the liquefier come out as a subcooled liquid, for storage or return to the air separation plant. This new liquefier does not include a front end electrical compressor, and will take a self produced liquid nitrogen, pump it up to a runnable 420 psig pressure, and with the use of turbines, condensers, flash pots, and multi pass heat exchangers. The liquefier will make liquid from a planned amount of any pure gas oxygen or nitrogen an air separation plant can produce.

A BOG reliquefaction system includes: a compressor; a heat exchanger cooling the BOG compressed by the compressor through heat exchange using BOG not compressed by the compressor; a pressure reducer disposed downstream of the heat exchanger and reducing a pressure of fluid cooled by the heat exchanger; and a combination of a first temperature sensor disposed upstream of a cold fluid channel of the heat exchanger and a fourth temperature sensor disposed downstream of a hot fluid channel of the heat exchanger, combination of a second temperature sensor disposed downstream of the cold fluid channel of the heat exchanger and a third temperature sensor disposed upstream of the hot fluid channel of the heat exchanger, or combination of a first pressure sensor disposed upstream of the hot fluid channel of the heat exchanger and a second pressure sensor disposed downstream of the hot fluid channel of the heat exchanger.

Plant and process for the production of liquid methane from a feed gas stream comprising at least methane and carbon dioxide. A feed gas stream is injected into a CO.sub.2 crystallizer in countercurrent fashion against a stream of predominantly liquid methane, thereby crystallizing amounts of carbon dioxide from the feed gas stream. Gaseous methane recovered from the CO.sub.2 crystallizer is liquefied at a liquefaction exchanger.