F 1 In +a In 2 w a 0.5 1-0.41 +2.47h 2470411 1-0.5 =0.4088 =1.505 W 设馏出液的平均组成为 2021/2/21 上页下及2021/2/21       − − + − = 1 2 2 1 1 1 ln ln 1 1 ln x x x x W F         − − = + 1 0.5 1 0.411 2.47ln 0.411 0.5 ln 2.47 1 = 0.4088  =1.505 W F 设馏出液的平均组成为 y