Controlling apparatus and method

Claim 1

An apparatus for separately regulating the flow rates of first and second fluid streams joining one with the other to form a composite stream for maintaining said composite stream within a preselected composition range, comprising: first flow measuring means for measuring the flow rate of the first stream and delivering a signal A representative of that flow rate; second flow measuring means for measuring the flow rate of the second stream and delivering a signal B representative of that flow rate; an analyzing means associated with the composite stream for measuring at least one constituent of said composite stream and delivering a signal C representative of the relative amount of said constituent; a control means having a set point D and being connected to the analyzing means for receiving the signal C therefrom, comparing said signal C to the set point D and delivering a signal E responsive to the difference between the set point D and the signal C; a first control valve positioned in the first stream for regulating the flow rate of the first stream in response to a received signal; a conduit loop in communication with the first stream on opposed sides of the first control valve; a compressor positioned in the conduit loop; a second control valve positioned in the second stream for regulating the flow rate of the second stream in response to a received signal; a pressure control means associated with the first stream at a location upstream of the first control valve for measuring the pressure of said first stream, comparing said measurement to a set point, and delivering a signal F responsive to the difference between the set point value and the pressure measurement of the first stream; a first ratio relay means having a set point and being connnected to the first flow measuring means for receiving the signal A therefrom, multiplying said signal A by the set point, and delivering a signal G representative of said multiplication; a second ratio relay means having a set point and being connected to the second flow measuring means for receiving the signal B therefrom, dividing said signal B by the set point and delivering a signal H representative of said division; a first selective relay means connected to the first ratio relay means and the control means for receiving E and G, comparing said signals E and G one to the other, and delivering a signal I representative of the lower of said signals E and G; a first flow controller connected to the second ratio relay and the first flow measuring means for receiving signals A and H, comparing signals A and H one to the other and delivering a signal K responsive to the difference between signals A and H; a second selective relay means connected to the first flow controller, the first valve and the pressure control means for receiving signals F and K, comparing said signals F and K one to the other, and delivering s signal J representative of the higher of said signals F and H to the first valve for controlling the flow rate of the first stream relative to one of the flow rate of the second stream or the pressure of the first stream; and a second flow controller connected to the first selective relay, the second flow measuring means, and the second valve for receiving signals B and I, comparing signals B and I one to the other, and delivering a signal L responsive to the difference between signals B and I to the second valve for controlling the flow rate of the second stream relative to one of the flow rate of the first stream or the analysis of the composite stream.

Claim 2

An apparatus for separately regulating the flow rates of first and second fluid streams joining one with the other to form a composite stream for maintaining said composite stream within a preselected composition range, comprising: first flow measuring means for measuring the flow rate of the first stream and delivering a signal A representative of that flow rate; second flow measuring means for measuring the flow rate of the second stream and delivering a signal B representative of that flow rate; an analyzing means associated with the composite stream for measuring at least one constituent of said composite stream and delivering a signal C representative of the relative amount of said constituent; a control means having a set point D and being connected to the analyzing means for receiving the signal C therefrom, comparing said signal C to the set point D and delivering a signal E responsive to the difference between the set point D and the signal C; a first control valve positioned in the first stream for regulating the flow rate of the first stream in response to a received signal; a conduit loop in communication with the first stream on opposed sides of the first control valve; a compressor positioned in the conduit loop; a second control valve positioned in the second stream for regulating the flow rate of the second stream in response to a received signal; a pressure control means associated with the first stream at a location upstream of the first control valve for measuring the pressure of said first stream, comparing said measurement to a set point, and delivering a signal F responsive to the difference between the set point value and the pressure measurement of the first stream; a first ratio relay means having a set point and being connnected to the first flow measuring means for receiving the signal A therefrom, multiplying said signal A by the set point, and delivering a signal G representative of said multiplication; a second ratio relay means having a set point and being connected to the second flow measuring means for receiving the signal B therefrom, dividing said signal B by the set point and delivering a signal H representative of said division; a first selective relay means connected to the first ratio relay means and the control means for receiving E and G, comparing said signals E and G one to the other, and delivering a signal I representative of the lower of said signals E and G; a first flow controller connected to the second ratio relay and the first flow measuring means for receiving signals A and H, comparing signals A and H one to the other and delivering a signal K responsive to the difference between signals A and H; a second selective relay means connected to the first flow controller, the first valve and the pressure control means for receiving signals F and K, comparing said signals F and K one to the other, and delivering s signal J representative of the higher of said signals F and H to the first valve for controlling the flow rate of the first stream relative to one of the flow rate of the second stream or the pressure of the first stream; and a second flow controller connected to the first selective relay, the second flow measuring means, and the second valve for receiving signals B and I, comparing signals B and I one to the other, and delivering a signal L responsive to the difference between signals B and I to the second valve for controlling the flow rate of the second stream relative to one of the flow rate of the first stream or the analysis of the composite stream.

Claim 10

A method for regulating the flow rates of first and second fluid streams joining one with the other to form the composite stream for maintaining said composite stream within a preselected composition range, comprising: measuring the flow rate of the first stream; delivering a signal A representative of the flow rate of said first stream; measuring the flow rate of the second stream; delivering a signal B representative of the flow rate of said second stream; measuring at least one constituent of said composite stream; delivering a signal C representative of the relative amount of said measuring constituent; comparing signal C to a set point D; delivering a signal E responsive to the difference between the set point D and the signal C; measuring the pressure of said first stream; delivering a signal F responsive to the difference between a set point value and the pressure measurement of the first stream; multiplying signal A by a set point value; delivering a signal G representative of said multiplication; dividing signal B by a set point value; delivering a signal H representative of the quotient of a division of signal B by an associated set point value; comparing the signals E and G one to the other; delivering a signal I representative of the lower of said signals E and G; comparing signals A and H one to the other; delivering a signal K responsive to the difference between signals A and H; comparing signals F and K one to the other; delivering a signal J in response to the comparison; receiving signal J and controlling the flow rate of the first stream in response to said signal J; comparing signals B and I one to the other; delivering a signal L responsive to the difference between signals B and I; receiving signal L and controlling the flow rate of the second stream in response to said signal L.

Claim 11

A method for regulating the flow rates of first and second fluid streams joining one with the other to form the composite stream for maintaining said composite stream within a preselected composition range, comprising: measuring the flow rate of the first stream; delivering a signal A representative of the flow rate of said first stream; measuring the flow rate of the second stream; delivering a signal B representative of the flow rate of said second stream; measuring at least one constituent of said composite stream; delivering a signal C representative of the relative amount of said measuring constituent; comparing signal C to a set point D; delivering a signal E responsive to the difference between the set point D and the signal C; measuring the pressure of said first stream; delivering a signal F responsive to the difference between a set point value and the pressure measurement of the first stream; multiplying signal A by a set point value; delivering a signal G representative of said multiplication; dividing signal B by a set point value; delivering a signal H representative of the quotient of a division of signal B by an associated set point value; comparing the signals E and G one to the other; delivering a signal I representative of the lower of said signals E and G; comparing signals A and H one to the other; delivering a signal K responsive to the difference between signals A and H; comparing signals F and K one to the other; delivering a signal J in response to the comparison; receiving signal J and controlling the flow rate of the first stream in response to said signal J; comparing signals B and I one to the other; delivering a signal L responsive to the difference between signals B and I; receiving signal L and controlling the flow rate of the second stream in response to said signal L.