关于用distillation模块做萃取的热力学问题

srwyyj

选择 liquid-liquid 数学求解方法 提示如下错误：
1 error(s), 0 warning(s), and 0 message(s) detected:

*** error ***  Unit 1, 't1' - only vle thermodynamics was detected in the column, but the calculated phases option is set to vlle. To resolve, go to the main column. Either set the calculated phases option to vle, or add a vlle thermodynamic method set to the column.
不知道是什么问题，跪求大神们指点！