| 摘要 |
The invention relates to a process and an apparatus for product-conserving thermal dissociation of halogenated aliphatic hydrocarbons, preferably for thermal dissociation of 1,2-dichloroethane to vinyl chloride. This uses chemical dissociation promoters and/or physical measures which initiate the dissociation reaction. The initiation of the dissociation reaction, with the same conversion, lowers the temperature level in the reaction mixture and the temperature of the dissociation gas on exit from the dissociation furnace. The amount and the exit temperature of the flue gas from the radiation zone of the dissociation furnace likewise decrease at the same time. It order to be able to implement the product-conserving mode of operation in the radiation zone of the dissociation furnace and simultaneously to maintain the function of the convection zone, the heat input to the dissociation furnace is divided such that a portion of the heat introduced by underfiring is introduced by burners in the radiation zone, and the other portion of the heat supplied by underfiring is introduced by burners arranged at the exit of the flue gas from the radiation zone. The partial decoupling of the heat input of the radiation zone and of the convection zone makes possible a particularly product-conserving mode of operation. |
