초록 ▼

Improved operating efficiency is achieved in a PSA gas concentrator by connecting the primary product gas outlet end of a pressurized sieve bed with a gaseous mixture receiving end of a second molecular sieve bed between each pressure reversal portion of a PSA gas separation cycle. A cross over valv

Improved operating efficiency is achieved in a PSA gas concentrator by connecting the primary product gas outlet end of a pressurized sieve bed with a gaseous mixture receiving end of a second molecular sieve bed between each pressure reversal portion of a PSA gas separation cycle. A cross over valve (12) has a first mode (12a) in which a first bed (16) is connected to a source (10) of pressurized air and a second bed (18) is connected with an exhaust port (14), a second mode (12b) in which the second bed is connected with the source of pressurized air and the first bed is connected with the exhaust port, and a third mode (12c) in which the passage of gas between the pressurized air source, the exhaust port, and the first and second beds is prohibited. Check valves (50a, 50b, 50c, and 50d) and a pressure equalization valve (52) selectively interconnect second ends (22, 26) of one bed with the first ends (20, 24 ) of the other. Primary product valves (54a, 54b) selectively interconnect the sieve beds with a primary product outlet port (34) and to the other sieve bed by feedback restricters (36, 40). When the cross valve is in either the first or second mode (12a, 12b) the pressure equalization valve (52) is closed and the product valves are open. When the cross over valve is in the third mode (12c), the primary product valves (54a, 54b) are closed and the pressure equalization valve (52) is opened. This allows the primary product gas to pass from the output end of the pressurized bed into the input end of the purged bed.

대표청구항 ▼

A method of separating a high purity primary product gas from a gaseous mixture, the method comprising: directing the gaseous mixture into an input end of a first bed containing a molecular sieve material that selectively adsorbs a first component of the gaseous mixture and connecting an input end o

A method of separating a high purity primary product gas from a gaseous mixture, the method comprising: directing the gaseous mixture into an input end of a first bed containing a molecular sieve material that selectively adsorbs a first component of the gaseous mixture and connecting an input end of a second bed containing the molecular sieve material with an exhaust port; channeling a primary product gas from an output end of the first bed through first and second legs of a first T-connection to a primary product gas output port and feeding back a fraction of the primary product gas through first and second legs of a second T-connection into an output end of the second bed; disconnecting the first bed from the source of the gaseous mixture and the second bed from the exhaust port and equalizing the pressure in the beds by permitting gas from the first bed to flow through the first T-connection first leg, a third leg of the first T-connection, a first check valve, a downcomer line, a pressure equalization control valve, and a second check valve into the input end of the second bed until the pressures in the first and second beds are generally equal, such that at the end of the pressure equalization step, primary product poor gas is retained in the first T-connection first and third legs; connecting the second bed input end with a source of the gaseous mixture under pressure and connecting the first bed input end with the exhaust port such that primary product gas flows from the second bed output end through the second T-connection first and second legs to the product gas outlet port; feeding back a fraction of the primary product gas from the second bed output end through the first T-connection first and second legs sweeping the primary product poor gas from the first T-connection first leg into the first bed; when the pressure of the primary product gas in the first T-connection exceeds the pressure of the gas in the downcomer line, sweeping the primary product poor gas retained in the first T-connection third leg through the first check valve into the downcomer line such that it does not contaminate primary product gas passing to the product gas outlet port. A gas separation apparatus comprising: a first bed containing a molecular sieve material that selectively adsorbs at least a first component of a gaseous mixture and having a first bed first end and a first bed second end; a second bed containing the molecular sieve material and having a second bed first end and a second bed second end; a cross over valve means having three modes, a first mode in which the first bed first end is connected with a source of the gaseous mixture under pressure and the second bed first end is connected with an exhaust port, a second mode in which the second bed first end is connected with the source of the gaseous mixture under pressure and the first bed first end is connected with the exhaust port, and a third mode in which the passage of gas between the source of gaseous mixture under pressure, the exhaust port, and the first and second bed first ends is blocked; a product gas outlet port operatively connected with the first bed second end and the second bed second end; a feedback means for selectively feeding back a portion of the primary product gas passing from the first bed second end to the second bed second end and for selectively passing a fraction of the primary product gas passing from the second bed second end to the first bed second end; and, a pressure equalizing means for selectively interconnecting the first bed second end with the second bed first end and the second bed second end with the first bed first end, the pressure equalizing means including: a first T-connection having a first leg connected with the first bed second end, a second leg connected with the feedback means, and a third leg connected directly with a first check valve without an intervening control valve, which first check valve is connected directly to a first end of a downcomer line without intervening controlled valves such that when the feedback means is passing primary product gas to the first bed second end, the primary product gas flushes breakthrough gas from the first and second legs and their respective interconnecting tubing back into the first bed second end and when the pressure of primary product gas in the first T-connection exceeds the pressure in the downcomer line, the primary product gas pushes the breakthrough gas in the third leg through the first check valve into the downcomer line; a second T-connection having a first leg connected with the second bed second end, a second leg connected with the feedback means, and a third leg connected directly with a second check valve which is connected directly to the downcomer line first end without intervening controlled valves, such that when the feedback means is passing primary product gas to the second bed second end, the primary product gas flushes breakthrough gas from the first and second legs and respective interconnecting tubing back into the second bed second end and when the pressure of the primary product gas in the second T-connection exceeds the pressure in the downcomer line, the primary product gas pushes the breakthrough gas in the third leg through the second check valve into the downcomer line; a valving means which selectively connects a second end of the downcomer line with the first bed first end and the second bed first end.