In-situ gas blending and dilution system for delivery of dilute gas at a predetermined concentration

A system for delivery of dilute gases, comprising:

• an active gas source;
• a diluent gas source;
• a gas flow metering device for dispensing of the active gas at a predetermined flow rate;
• a mixing device arranged to mix active gas from the active gas source that is dispensed at said predetermined flow rate by the gas flow metering device, with diluent gas to form a diluted active gas mixture without subsequent further dilution of the diluted active gas mixture by additional diluent gas;
• and
• a monitor arranged to measure concentration of active gas in the diluted active gas mixture, and responsively adjust the gas flow metering device, to control the dispensing rate of the active gas, and maintain a predetermined concentration of active gas in the diluted active gas mixture,
• wherein the gas flow metering device comprises a mass flow controller, and the monitor being arranged to produce an output control signal correlative to sensed active gas concentration in the diluted active gas mixture, with the control signal being transmitted to the mass flow controller to modulate the set point thereof to achieve a predetermined constant active gas concentration in the diluted active gas mixture, and wherein diluent gas is flowed to said mixing device without passage through a mass flow controller or flow restriction element.

A system for delivery of dilute fluid, comprising:

• an active fluid source;
• a diluent fluid source;
• a fluid flow metering device for dispensing of the active gas at a predetermined flow rate;
• a mixing device arranged to mix active fluid from the active fluid source that is dispensed at said predetermined flow rate by the fluid flow metering device, with diluent fluid to form a diluted active fluid mixture;
• and
• a monitor arranged to measure concentration of active fluid in the diluted active fluid mixture, and responsively adjust the fluid flow metering device, to control the dispensing rate of the active fluid, and maintain a predetermined concentration of active fluid in the diluted active fluid mixture,
• wherein the diluent fluid is flowed to said mixing device without passage through a mass flow controller or flow restriction element.

A method for delivery of dilute gas, comprising:

• providing an active gas source and a diluent gas source;
• controllable dispensing active gas from the active gas source at a predetermined flow rate;
• mixing active gas from the active gas source that is dispensed at said predetermined flow rate, with diluent gas from the diluent gas source, in a mixing device, to form a diluted active gas mixture;
• and
• monitoring concentration of active gas in the diluted active gas mixture, and responsively adjusting the dispensing rate of the active gas, to maintain a predetermined concentration of active gas in the diluted active gas mixture,
• wherein the diluent gas is flowed to said mixing device without passage through a mass flow controller or flow restriction element.

A method for delivery of dilute gas, comprising:

• providing an active gas source and a diluent gas source;
• controllably dispensing active gas from the active gas source at a predetermined flow rate;
• mixing active gas from the active gas source that is dispensed at said predetermined flow rate, with diluent gas from the diluent gas source, to form a diluted active gas mixture;
• and
• monitoring concentration of active gas in the diluted active gas mixture, and responsively adjusting the dispensing rate of the neat active gas, to maintain a predetermined concentration of active gas in the diluted active gas mixture, wherein the monitoring step utilizes multiple gas monitoring devices and a signal processor unit, each of the multiple gas monitoring devices generates an output correlative of concentration of active gas in the diluted active gas mixture, and each such output is transmitted to the signal processor unit for processing, and the signal processor unit is arranged to transmit a control signal derivative of the outputs of the multiple gas monitoring devices to responsively adjust the gas flow metering device, to control the dispensing rate of the active gas, and maintain the predetermined concentration of active gas in the diluted active gas mixture.

A method for delivery of dilute fluid, comprising:

• providing an active fluid source and a diluent fluid source;
• controllably dispensing active fluid from the active fluid source at a predetermined flow rate;
• mixing active fluid from the active fluid source that is dispensed at said predetermined flow rate, with diluent fluid from the diluent fluid source, in a mixing device, to form a diluted active fluid mixture;
• and
• monitoring concentration of active fluid in the diluted active fluid mixture, and responsively adjusting the dispensing rate of the active fluid, to maintain a predetermined concentration of active fluid in the diluted active fluid mixture,
• wherein the diluent fluid is flowed to said mixing device without passage through a mass flow controller or flaw restriction element.

A system for delivery of dilute gases, comprising:

• an active gas source;
• a diluent gas source;
• a gas flow metering device for dispensing of the active gas at a predetermined flow rate;
• a dynamic mixing device arranged to mix active gas from the active gas source that is dispensed at said predetermined flow rate by the gas flow metering device, with diluent gas to form a diluted active gas mixture;
• and
• a monitor arranged to measure concentration of active gas in the diluted active gas mixture, and responsively adjust the gas flow metering device, to control the dispensing rate of the active gas, and maintain a predetermined concentration of active gas in the diluted active gas mixture;
• wherein the dilient gas is flowed to the dynamic mixing device without passage through a mass flow controller or flow restriction element.

A system for delivery of dilute gases, comprising:

• an active gas source;
• a diluent gas source;
• a gas flow metering device for dispensing of the active gas at a predetermined flow rate;
• a mixing device arranged to mix active gas from the active gas source that is dispensed at said predetermined flow rate by the gas flow metering device, with diluent gas to form a diluted active gas mixture;
• and
• a monitor arranged to measure concentration of active gas in the diluted active gas mixture, and responsively adjust the gas flow metering device, to control the dispensing rate of the active gas, and maintain a predetermined concentration of active gas in the diluted active gas mixture, wherein the monitor comprises multiple gas monitoring devices and a signal processor unit, each of the multiple gas monitoring devices generates an output correlative of concentration of active gas in the diluted active gas mixture, and each such output is transmitted to the signal processor unit for processing, and the signal processor unit is arranged to transmit a control signal derivative of the outputs of the multiple gas monitoring devices to responsively adjust the gas flow metering device, to control the dispensing rate of the neat active gas, and maintain the predetermined concentration of active gas in the diluted active gas mixture.