Patent ID: 7115152

Claim:
A regenerable filter system comprising: a flow path along which a stream of fluid flows between an inlet and an outlet; a first filtering unit in said flow path between said inlet and said outlet, said first unit comprising first and second regenerable filter beds, each bed including a first adsorbent for removing a first contaminant from said stream of fluid; a first valve located between said inlet and said first and second filter beds for selectively directing said stream of fluid through either one of said first and second filter beds, the other of said first and second filter beds being removed from said flow path; a second filtering unit in said flow path between said first filtering unit and said outlet, said second unit being located downstream from said first unit and including third and fourth regenerable filter beds, each bed including a second adsorbent for removing a second contaminant from said stream of fluid; a second valve located between said first filtering unit and said third and fourth filter beds for selectively directing said stream of fluid through either one of said third and fourth filter beds independent of said first valve, the other of said third and fourth filter beds being removed from said flow path; and, a controller, said controller operating said first valve to direct said stream of fluid through a desired one of said first and second filter beds and operating said second valve to direct said stream of fluid through a desired one of said third and fourth filter beds, wherein said first and second filtering units are operated independent of one another.