Modification Of Extractive Distillation For Butadiene Unit And Optimization Discussions

After the new butadiene unit of Lanzhou Petrochemical Company was put into production in Oct. 2006, the difference pressure of the first and second extraction columns was high and the capacity of the unit could not reach the design value. The quality of the production was not steady and the actual value of the energy consumption of the unit was higher than that of the design. Affected by the foregoing towers, the load of the revamping de-light and revamping de-heavy towers was not fulfilled the design value and the whole unit did not work well. Perhaps small area of the open hole of the towers and lower value of fluid descending pipe gap were main reason. In order to solve these problems, some modifications have been adapted based on hydraulic recalculation. By increasing the open hole area of the towers and fluid descending pipe gap value, the difference pressure of the towers was greatly decreased and the qualities of the productions were significantly improved. Meanwhile, the temperature of the towers bottom was dropped observably. The energy was saved since the steam consumption was declined. To compare difference pressure of the towers, yield, as well as the quality of the productions, the modification of extractive distillation for butadiene unit was proved to be successful. Moreover, optimization for butadiene unit was also discussed in this thesis.