Temperature-based estimation of remaining absorptive capacity of a gas absorber

A method of estimating remaining absorptive capacity of a CO2 absorber in a re-breather system, said method comprising the steps of:

• passing exhaled CO2 gas from said re-breather system through said CO2 absorber;
• distributing a plurality of temperature sensors throughout said CO2 absorber wherein said plurality of temperature sensors includes a first temperature sensor positioned where said exhaled CO2 enters said CO2 absorber and subsequent temperature sensors spaced apart in said CO2 absorber;
• measuring a temperature at each of said plurality of temperature sensors;
• determining temperature differences between each of said subsequent temperature sensors and said first temperature sensor;
• normalizing each of said temperature differences to a largest one of said temperature differences wherein corresponding normalized temperature differences are generated;
• and
• comparing said normalized temperature differences with an experimentally-determined calibration function to determine the remaining absorptive capacity of said CO2 absorber.

A system for estimating remaining absorptive capacity of a gas absorber that absorbs a gas during an exothermic or endothermic reaction therewith, said gas absorber having an inlet receiving a flow of said gas and defining a flow path therethrough along which said gas flows, wherein a reaction gas is produced by said reaction, said reaction gas exiting said gas absorber at an outlet thereof, said system comprising:

• a plurality of temperature sensors distributed along said flow path wherein said plurality of temperature sensors includes a first temperature sensor positioned at said inlet and subsequent temperature sensors spaced apart along said flow path, wherein each of said plurality of temperature sensors can measure a temperature;
• means for determining temperature differences between each of said subsequent temperature sensors and said first temperature sensor;
• means for normalizing each of said temperature differences to a largest one of said temperature differences wherein corresponding normalized temperature differences are generated;
• means for comparing said normalized temperature differences with an experimentally-determined calibration function to determine the remaining absorptive capacity of said gas absorber;
• and
• means for displaying a visual representation of the remaining absorptive capacity.