Abstract: A compression machine (compressor 4 and/or pump 5) of the plant (1) for the treatment of a fluid, typically by pressure swing adsorption, comprises at least one detector (7) for detecting clearance between a moving part (6) and a stator and delivering a measurement signal used so as to vary, depending on this measurement, the operation of the plant and especially to automatically shorten the phases during which the machine is running at an excessively high speed.

Abstract: A repressurization phase of an adsorber comprises a step of first countercurrent repressurization with at least gas from a first co-current decompression of another adsorber, this phase ending in a step of co-current production. Immediately following the first countercurrent repressurization step, air is introduced co-current into the adsorber.

Abstract: A compression machine (compressor 4 and/or pump 5) of the plant (1) for the treatment of a fluid, typically by pressure swing adsorption, comprises at least one detector (7) for detecting clearance between a moving part (6) and a stator and delivering a measurement signal used so as to vary, depending on this measurement, the operation of the plant and especially to automatically shorten the phases during which the machine is running at an excessively high speed.

Abstract: The cycle employed is of the transatmospheric type with the use of a production buffer tank (C1), and with a purge/elution phase close to the low pressure in which gas output by another adsorber in the first cocurrent decompression phase is introduced in countercurrent into the adsorber (A, B) and, simultaneously, the countercurrent pumping is continued. During the production step, the oxygen produced is also sent into an auxiliary tank (C2), and the gas contained in this auxiliary tank is, with regard to the adsorber, used solely during a fraction of the pressurization phase of the adsorber.

Abstract: According to this process, in the case of a reduction in the production rate, the maximum pressure PM of the cycle is lowered and the ratio of this maximum pressure to the minimum pressure Pm of the cycle is reduced, in particular by altering the durations of compression and decompression stages. The process is applicable to the production of oxygen at variable rate.

Abstract: A PSA process for the separation of a gas flow containing essentially oxygen and nitrogen by preferential adsorption of the nitrogen, at a high adsorption pressure, on at least one bed of adsorbent material inserted in at least one separation zone. The material preferentially adsorbs nitrogen. Each bed of adsorbing material is subjected to successive separation cycles. Each separation cycle comprises at least: a purge phase comprising a desorption of the nitrogen adsorbed on the adsorbing material at a low desorption pressure below the high adsorption pressure, and a supply phase comprising introduction of the gaseous flow at a supply temperature (T.sub.sup) into the separation zone with passage from the low desorption pressure to the high adsorption pressure. The supply temperature (T.sub.sup) of the gaseous flow to be separated is regulated and the high adsorption pressure is adjusted.

Abstract: The apparatus for the separation of a gas mixture by pressure swing adsorption (PSA) comprises at least one adsorber A and a first vessel T which can be selectively connected to the adsorber in order temporarily to store the gas which is extracted from the adsorber and reintroduced into it during a cycle, the vessel T having a fixed free internal volume V, a vertical main direction of height h, with the relationship 25.ltoreq.h.sup.3 /V.ltoreq.150, and the gas fraction entering and leaving the vessel T at its lower part, and remaining therein for a time which does not exceed 300 seconds. The apparatus is useful in the production of oxygen or hydrogen.