A heat exchanger can be configured to utilize multiple sections of hardway fins that can be configured so that an upper first section of the fins can build up liquid head and a second lower section of the fins can be configured to distribute liquid in an even, or uniform, manner. The first section of fins can utilize a different type of hole arrangement than the second section of fins. For instance, the diameter or width of the holes in the first section may differ from the diameter or width of the holes of the second section. In addition (or as an alternative), fin frequency and/or spacing between immediately adjacent holes in the first section of fins may be different from the spacing between immediately adjacent holes in the second section of fins.

A heat exchanger can be configured to utilize multiple sections of hardway fins that can be configured so that an upper first section of the fins can build up liquid head and a second lower section of the fins can be configured to distribute liquid in an even, or uniform, manner. The first section of fins can utilize a different type of hole arrangement than the second section of fins. For instance, the diameter or width of the holes in the first section may differ from the diameter or width of the holes of the second section. In addition (or as an alternative), fin frequency and/or spacing between immediately adjacent holes in the first section of fins may be different from the spacing between immediately adjacent holes in the second section of fins.

Method and device for generating gaseous compressed nitrogen by the low-temperature separation of air in a distillation column system, having a pre-column, a high-pressure column and a low-pressure column. The feed air is compressed, purified in a purification apparatus and cooled. A first sub-flow of the cooled feed air is introduced in a predominantly liquid state into the distillation column system. A gaseous fraction from the pre-column in introduced into the liquefaction chamber of a pre-column head condenser with liquid formed therein fed as reflux into the pre-column. A first gaseous nitrogen product fraction is drawn from the high-pressure column, heated, and obtained as first gaseous compressed nitrogen product. At least a part of the second sub-flow is introduced into the evaporation chamber of the pre-column head condenser. A third sub-flow of the cooled feed air is expanded to perform work and subsequently introduced into the liquefaction chamber.

A tube heat exchanger extending in a vertical direction, comprising: a first chamber including a lower portion provided with at least one intake inlet for a diphasic fluid including a liquid and a first vapor containing a mist; an upper portion; and a first recovery member passed through by the first vapor and recovering the mist in liquid form, the first vapor next arriving in the upper portion, a central chamber forming liquid films running over the tubes and vaporizing at least partially to produce a second vapor, the tubes being traveled inwardly by a fluid hotter than the diphasic fluid, and a second chamber receiving the first vapor and the second vapor to form a third vapor, and including an outlet for the non-vaporized liquid and an outlet for the third vapor, the first chamber and the second chamber together forming a volume surrounding the central chamber around the vertical direction.

A system and method for removing nitrogen and producing a high pressure methane product stream and an NGL product stream from natural gas feed streams where at least 90%, and preferably at least 95%, of the ethane in the feed stream is recovered in the NGL product stream. The system and method of the invention are particularly suitable for use with feed streams in excess of 5 MMSCFD and up to 300 MMSCFD and containing around 5% to 80% nitrogen. The system and method preferably combine use of strategic heat exchange between various process streams with a high pressure rectifier tower and the ability to divert all or a portion of a nitrogen rejection unit feed stream to optionally bypass a nitrogen fractionation column to reduce capital costs and operating expenses.

A moderate pressure nitrogen and argon producing cryogenic air separation unit is provided that includes a three distillation column system and turbine air stream bypass arrangement or circuit. The turbine air stream bypass arrangement or circuit is configured to improve argon and nitrogen recoveries in select operating modes by optionally diverting a portion of the turbine air stream to a nitrogen waste stream circuit drawn from the lower pressure column of the cryogenic air separation unit such that the diverted portion of the turbine air stream bypasses the distillation column system.

A method for separating a gas mixture comprising carbon monoxide, nitrogen and hydrogen involves sending a hydrogen-depleted fluid to a denitrification column (K2) having a top condenser (C1) and a bottom reboiler (R2) in order to produce a nitrogen-enriched gas at the top of the column and a nitrogen-depleted liquid at the bottom of the column, cooling the condenser of the denitrification column by means of a nitrogen cycle using a nitrogen compressor (V1, V2, V3), vaporising, in the heat exchanger of the condenser, the liquid nitrogen (53) from the nitrogen cycle, and returning the nitrogen (55) vaporised in the heat exchanger to the nitrogen compressor.

The invention relates to a heat exchanger for vaporizing a coolant fluid by heat exchange with a calorigenic fluid, said exchanger comprising several parallel plates defining a plurality of passages between them which are suitable for the coolant fluid or calorigenic fluid to flow, a first wave and a second wave extending between two successive plates so as to define a plurality of channels within the same passage, said first and second waves comprising two adjacent edges, at least one assembly member extending from one edge to the other so as to connect the waves to one another. According to the invention, the assembly member is forcibly engaged in at least one part of a channel of the first wave on one hand, and in at least one part of a channel of the second wave on the other hand

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.

The present invention relates to a cryogenic air separation process that provides high pressure oxygen for an oxy-fired combustion of a fuel (e.g., a carbonaceous fuel). The air separation process can be directly integrated into a closed cycle power production process utilizing a working fluid, such as CO.sub.2. Beneficially, the air separation process can eliminate the need for inter-cooling between air compression stages and rather provide for recycling the adiabatic heat of compression into a process step in further methods wherein an additional heat supply is beneficial.