How does the scrubber work that cleans the air of CO2 on Alvin?

The CO2 scrubber is an electric device like a vacuum cleaner that hangs in the rear of the sub’s cockpit. An electronic monitor provides a read-out of the level of CO2 in the cockpit atmosphere and it is the pilot's responsibility to periodically check that the CO2 is not too high. When necessary, the CO2 scrubber is turned on and the air is sucked through a canister of special pellets that react with the CO2 to absorb and remove the CO2 from the atmosphere. Two new canisters are placed in the cockpit before each dive and the used ones are removed after each dive. In addit9on, Alvin carries two emergency canisters of lithium hydroxide to use for CO2 removal if the sub needs to stay down longer. The combination of these four canisters provide for 72 hours of CO2 removal.

George Meier
Electrical Technician, Alvin group

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