HEATLESS ADSORBENT FRACTIONATORS WITH MICROPROCESSOR CYCLE CONTROL AND PROCESS

A method and apparatus are provided for adsorbing one or more first gases from a mixture thereof with a second gas to reduce the concentration of first gas in the mixture to below a permissible maximum concentration. The flow rate, inlet and outlet temperatures, inlet and outlet pressures and regenerating pressures are sensed, and the sensed information fed to a microprocessor programmed to calculate the quantity of purge required to regenerate the adsorbent bed off-stream for regeneration, calculate the purge flow rate, and, based on these calculations, control the regeneration time so that purge flow ceases when the adsorbent bed has been regenerated, control the cycling time, and switch the adsorbent beds at the end of each cycle period. The system is particularly applicable to the drying of gases.