| 摘要 |
PURPOSE:To improve removing efficiency of hydrocarbons from feed gas by withdrawing a portion of the feed gas before a catalyst tank and determining the concn. of CO2 after burning the gas completely, determining also the concn. of CO2 at the downstream side of the catalyst tank, and controlling the flow rate of O2 to be added based on the difference between both CO2 concn. CONSTITUTION:A portion of feed gas supplied from a duct 11 is fed to a combustion device 3 together with sufficient amt. of O2 through a duct 15 where it is burnt completely and the concn. of generated CO2 is determined by a densitometer 7. Hydrocarbons in the feed gas fed to the catalyst tank 1 together with O2 is burnt in the catalyst tank 1 and the CO2 concn. of the gas is determined at the downstream side of the catalyst tank 1 with a densitometer 8. Both determined values A1 and A2 of the CO2 concn. and flow rate Q0 are inputted to an operating device 10 and a set value for optimum flow rate Qs for O2 is decided, which is outputted to a flow rate controller 6 to control a controlling valve 2 and the amt. of O2 to be added appropriately. |
