摘要 |
A method for reducing hydrocarbon emissions from automotive evaporative emissions control systems comprising steps of: contacting a vented fuel vapor stream from a fuel tank (1) with a first passive purge canister bed (5), the passive purge canister bed comprising a vapor adsorbent material and including a passive purge vapor inlet and a passive purge vapor outlet for vapor stream flow, -contacting a vapor stream from the passive purge vapor outlet with an active purge canister bed, the active purge canister bed (2) comprising a vapor adsorbent material; contacting the active purge canister bed with mechanically convected purge air, wherein the mechanically convected purge air is prevented from flowing through the passive purge canister bed; and contacting the passive purge canister bed with fresh purge air drawn passively by the fuel tank through the passive purge vapor outlet without first contacting said active purge canister bed. |