DE202008013444U1 - Condenser-evaporator - Google Patents

Abstract

Condenser-evaporator with liquefaction passages for at least partial condensation of a Gas stream and with evaporation passages for at least partial Evaporation of a cooling fluid at the liquefaction passages as reflux passages and the evaporation passages for upward evaporation are formed of the cooling fluid.

Description

The The invention relates to a condenser-evaporator.

It Both return condensers are known, the liquefaction passages for at least partial condensation of a gas stream, as also "forced flow" evaporator with evaporation passages for upward evaporation of the cooling fluid.

Of the Invention is based on the object, a condenser-evaporator and a method to operate this, specify that economically are particularly favorable.

These Task is achieved by the features of the protection claim 1. In the context of the invention, it has been found that the combination of Return passages and upflow passages offers special advantages in the same condenser-evaporator.

Under "Reflux condenser" (also called dephlegmator) is understood here a heat exchanger, the return passages having. These return passages are steamed from below (here: Overhead gas of the single column). This condenses when ascending in the return passages at least partially. The return passages are designed so that the condensed liquid is not entrained, but flows down. By the counterflow of vapor and liquid Rectification takes place in the return passages. The condensate that exits at the lower end is at low volatility Components enriched, the steam exiting overhead at more volatile.

There are various types of flyback capacitors known. The heat exchanger block (or even a plurality of heat exchanger blocks) may be arranged inside a pressure vessel, as described, for example, in US Pat EP 1189000 A2 is shown, or the heat exchanger block is completed on all sides by headers, see for example US 6128920 , Alternatively, the reflux condenser may be installed in the top of a separation column with the return passages in communication with the top of the separation column at its lower end, see German patent application 10 2006 037 058 and corresponding applications. The return passages may also be filed according to one of the embodiments of the simultaneously filed German patent application 10 2007 035 619.8 (Applicant's internal file: P07117-DE / AVA = EM-AVA2700) and the corresponding applications. The one or more heat exchanger blocks of the reflux condenser are preferably designed as a plate heat exchanger, in particular as a brazed aluminum plate heat exchanger.

spatial Terms like "top", "bottom", "side", etc. refer to here always on the orientation of the single column and the reflux condenser in the intended operation.

Reflux passages not only allow a heat exchange, but also a mass transfer between in the return passages ascending gas and the liquid flowing down there, similar like the corrugated packs of a mass transfer column. This release effect can be described as HETP value (Height Equivalent to one Theoretical Plate = height of a theoretical soil). The HETP value of the capacitor is in the range of 300 to 600 mm. This works, for example, a 1.5 m high reflux condenser like up to five theoretical plates.

The inventive combination with evaporation passages, passed through the cooling fluid in the upward direction is ("forced flow" evaporator) gives a particularly favorable Course of the temperatures of evaporating cooling fluid and condensing Gas flow over the height of the condenser-evaporator.

Further Embodiments of the invention are in the claims 2 to 5 called.

Further The invention relates to a device for cryogenic separation of air according to protection claim 6.

The Invention and further details of the invention are hereinafter based on an embodiment schematically shown in the drawing explained in more detail, in which a condenser-evaporator according to protection claim 1 as a head capacitor of Single column of a cryogenic air separation plant used becomes.

Atmospheric air 1 is after compaction, cleaning and cooling (not shown) under an absolute pressure of 5 to 12 bar, preferably about 8 bar in the single column 2 initiated immediately above the swamp.

The top condenser 3 the single column 2 is inventively designed as a reflux condenser. Nitrogen-rich gas from the head of the single column flows down into the return passages (arrow up) and is partially condensed there. The condensate generated in this case flows in countercurrent to the rising gas in the return passages down (arrow down) and is in the single column 2 used as a liquid reflux. (A part may be at Be may be removed as a liquid product.) The gaseous remaining fraction is at the top of the return passages on a side header 4 as a pressure nitrogen stream 5 withdrawn and recovered after warming in a main heat exchanger, not shown as pressure nitrogen product.

An oxygen-enriched fraction 6 is liquid discharged from the bottom of the single column, in a throttle valve to a pressure of 1.3 to 4.5 bar, preferably about 2.5 bar relaxed and a lateral lower header 8th in the evaporation passages of the top condenser 3 introduced, which are operated as a forced flow evaporator. The fully evaporated oxygen-rich fraction 10 is via an upper header 9 withdrawn from the evaporation passages and, for example in a residual gas turbine (not shown) can be relaxed work. After heating in the main heat exchanger (not shown), it is withdrawn as a residual stream, used for regeneration of an adsorber for air purification or used as an oxygen-enriched product.

One Retrace capacitor in one of the embodiments mentioned here can also be used as the top condenser of a column of a two- or Multi-column method used for nitrogen-oxygen separation be, for example, as the main capacitor of a classic double column.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 1189000 A2 [0006]
• - US 6128920 [0006]
• - DE 102006037058 [0006]
• - DE 102007035619 [0006]

Claims (6)

Condenser evaporator with liquefaction passages for at least partial condensation of a gas stream and with evaporation passages for at least partial evaporation of a cooling fluid at the liquefaction passages as return passages and the evaporation passages for the upward evaporation of the Cooling fluids are formed. Condenser-evaporator according to claim 1, characterized in that that a gas flow in the lower area of the return passages and a liquid cooling fluid stream in the lower Range of evaporation passages are initiated. Condenser-evaporator according to claim 1 or 2, characterized characterized in that the cooling fluid in the evaporation passages is completely evaporated. Condenser-evaporator according to claim 2 or 3, characterized characterized in that the gas flow in the return passages only partially liquefied and from the upper area the return passages a gaseous remaining Electricity is deducted. Condenser-evaporator for cryogenic separation of air, in which a the method according to one of the claims 2 to 4 for condensing a top gas stream of at least one separation column, in particular a single column, a high-pressure column, a crude argon column or pure argon column is used. Apparatus for the cryogenic separation of air, in which a condenser-evaporator according to claim 1 as a top condenser at least one separation column, in particular a single column, a high pressure column, a crude argon column or Reinargonsäule, is used.