Abstract:
Indirect heat exchanger, of the type comprising a series of parallel plates (7) delimiting between themselves passages (8A, 8B; 28, 42, 60) of generally plate form containing undulant spacers (9; 32, 34, 36, 37, 44, 47, 48, 53 to 56). A first assembly (8A; 28, 60) of these passages constitutes thermal exchange passages having structure (3 to 5; 39 to 41, 51) for inlet and outlet of fluids adapted to exchange heat with each other. Over at least a portion of its length and of its width, the exchanger has added passages (8B; 42), in reduced or no heat exchange relation with the thermal exchange passages (8A; 28, 60) and provided to fulfill at least one function in addition to the exchange of heat, namely a function of storing liquid and/or recirculation of liquid and/or liquid-vapor separation.
Abstract:
To regenerate the adsorbent which serves to purify compressed air from water and carbon dioxide, there is used residual gas from an air distillation apparatus (10), heated to a substantially constant moderate regeneration temperature between the temperature of the air entering the mass of adsorbent and a temperature which is at most about 50.degree. C. higher, preferably about 10.degree. to 20.degree. C. higher, than this entering air temperature. This gas is then sent to a water refrigeration tower (16) for cooling the compressed air.
Abstract:
Process and installation for the production of ultrapure nitrogen by distillation of air, wherein the air to be treated is separated in a first column (6) into nitrogen at the head and liquid at the bottom rich in oxygen. The nitrogen in the head is used to circulate in a refrigeration cycle, a flow of high pressure cycle nitrogen being purified from hydrogen in a second column (7) comprising a bottom vaporizer (11) which ensures the condensation of this nitrogen before its introduction into this second column, and a head condenser (10) cooled by the bottom liquid of the first column (6). The ultra-pure production nitrogen is withdrawn (at 24) from the bottom of the second column (7), and a second high pressure cycle nitrogen flow is condensed (in 10; 10A) by vaporization of the bottom liquid of the first column (6). At least a portion of the nitrogen condensed by vaporization of bottom liquid of the first column (6) is purified of hydrogen in the second column (7), and at least a portion of the nitrogen condensed by vaporization of bottom liquid in the first column (6) is introduced as reflux into the head of the first column (6).
Abstract:
In this process for the distillation of air, of the type with a liquid oxygen pump (14) and with the vaporization of liquid oxygen under pressure, there are used, in addition to a principal compressor (1), at least three further compressors (9 to 11 ), of which two (9, 10) are mounted in series and supply the heat exchange line with air at a high pressure of the vaporization of oxygen. Air is withdrawn between these two further compressors, expanded to the medium pressure and introduced at the base of the medium pressure column (5), and at least one (11) of the three further compressors consumes the mechanical energy developed by the turbine (12).
Abstract:
A column (4) for producing nitrogen comprises, below the air introduction point, a section (17, 18) enriched in oxygen and a sump reboiler (9) supplied by recycled high pressure nitrogen. The expanded liquid (at 19) for supplying the overhead condenser (8) is withdrawn at an intermediate level between the level of air introduction and the reboiler, and the liquid in the sump of the column, after vaporization, constitutes a minority product of the installation consisting essentially of oxygen.