摘要:
A nitrogen generator for producing nitrogen gas from air having a plurality of stages of membrane units each containing a plurality of hollow fiber membranes having a feed input at least one of the plurality of membrane units containing a sweep input to inject a sweep gas longitudinally on the external surface of the hollow fiber membranes, the generator further containing:a) a conduit for collecting a non-permeate stream of a membrane stage N and using the same as a feed stream for a membrane stage N+1;b) a conduit for collecting only a permeate stream from at least the membrane stage N, and feeding all of the permeate stream from the membrane stage N to a sweep input of at least one previous membrane stage, such that the sweep gas is injected longitudinally and counter-current to the non-permeate gas on the external surface of the hollow fiber membranes, and that the sweep gas is mixed with the gas permeating through the hollow fiber membranes to make the permeate stream; andc) a conduit for collecting a permeate of a first membrane stage and a non-permeate of the last membrane stage.
摘要:
A gas under pressue is sent to a first compartment of a separation module having permeation membrane, the first modified gas mixture which exits from the first compartment being introduced into the enclosure to constitute therein a controlled atmosphere which is removed and circulated in counter-current in the second compartment of the module towards the discharge orifice of the latter so as to substantially recombine the two gaseous modified mixtues before discharging same thereby increasing the performances of the separation module.
摘要:
A process for treating a gaseous mixture, particularly air, by pressure swing adsorption (PSA), of the type in which three adsorbers (1 to 3) are used in each of which is carried out, for a given nominal production, a cycle comprising the following successive stages, the cycle being offset from one adsorber to the other by a third of the nominal duration (T) of the cycle:(a) a substantially isobaric adsorption phase at a high pressure (PM) of the cycle, by circulation of the mixture through the adsorber in a so-called co-current direction;(b) a desorption phase comprising a stage (b2) of pumping to a low pressure (P.sub.m) of the cycle less than atmospheric pressure, via a vacuum pump (7) of constant speed and continuous operation whose output is in the vicinity of atmospheric pressure; and(c) a repressurization phase of the adsorber to the high pressure of the cycle. During a reduction of the production flow rate, the mean intake pressure of the vacuum pump is raised for the duration of the cycle.
摘要:
A membrane nitrogen generator adapted to deliver a flow rate of nitrogen gas having a purity at least equal to P.sub.0, which contains:a) a source of compressed nitrogen containing gas having a purity lower than P.sub.0, the source having a maximum flow rate Fm.sub.1 ;b) a varyer connected to the source, which is adapted to vary the flow rate of the source between Fm.sub.1 and 0;c) a nitrogen membrane fed by the source which is capable of delivering a low purity nitrogen gas having a purity P.sub.1, which purity is lower than P.sub.0 at the maximum flow rate Fm.sub.1 ;d) a source of high purity compressed nitrogen gas having a purity which is greater than P.sub.0 which has a controllable flow rate of from 0 to a maximum flow rate value of Fm.sub.2 ;e) a mixer; andf) a purity controller.
摘要:
A wallpaper applicator for single-handedly applying on a flat surface and in a single continuous stroke the sticky face of a wallpaper. The applicator is characterized in that it eliminates distortion of the wallpaper and formation of air bubbles in between the wallpaper and the applied surface. The device comprises an elongated cross-sectionally polygonal casing in which lies a web of wallpaper; the latter is biased against two of the flat side walls of the casing by a weight rod engaged in the cylindrical hollow defined by the wallpaper web. One casing flat side wall defines a longitudinal slot through which escapes the leading edge portion of the wallpaper.
摘要:
A process for operating a permeable membrane generator at above or below design conditions therefor, which entails adjusting the permeation temperature of a feed stream permeating said membrane generator by heating or cooling means, thereby providing a desired amount, purity and pressure of a product gas.
摘要:
A process for supplying nitrogen to at least two user stations, whose requirements as to nitrogen purity are different. Compressed air is passed from an air compressor (12) to at least one air treatment station (13) permitting effecting at least one of the following treatments of oil removal, filtering out a major portion of the particles, drying, and bringing the air to the desired temperature. The compressed air is then sent to a centralized gas separation unit (14), so as to produce at the outlet of the unit impure nitrogen of intermediate purity. The gas from the centralized separation unit (14) is directed to at least two utilization lines (3-5), each comprising a local gas separation unit (6-8), in which the gas is again treated, so as to obtain at the outlet of each local separation unit nitrogen of a purity suitable for the uses of each of the user stations (9, 10) at the end of the line.
摘要:
A process for generating a nitrogen-enriched gas from a feed stream of atmospheric air or a mixture of nitrogen which is not continuously supplied to a membrane system, which membrane system comprises a non-permeate side and a permeate side, and being more permeable to oxygen than nitrogen, which process entails feeding the feed stream side of the membrane, and recovering an oxygen enriched gas being recovered on the permeate side of the membrane system while a nitrogen-enriched gas is recovered from the non-permeate side of the membrane, wherein a feed back of nitrogen gas or nitrogen- containing gas having an oxygen gas concentration lower than 21% is supplied to the non-permeate side of the membrane system during at least a part of the period of time where the air feed stream is not supplied to the membrane system thereby avoiding any substantial retrodiffusion of oxygen through the membrane system from the permeate side to the non-permeate side of the membrane during those periods of time where the feed stream is not supplied to the membrane system.
摘要:
A membrane nitrogen generator exhibiting increased flexibility and productivity in response to changes in customer demand which entails a membrane generator capable of generating nitrogen of variable flow rate and purity, bulk storage capacity for storing nitrogen of a purity which is higher than that required by a customer and flow and purity controllers for delivery to a customer plant.
摘要:
A membrane nitrogen gas generator, containing a feed stream compressor, one or more filtering membranes, each having a permeate side and a non-permeate side, in fluid connection with and downstream of the feed stream compressor, and one or more product storage containers capable of storing a product having a higher purity than is required by customer demand, and which generator is capable of generating an increased flow rate during periods of high demand.