[6-1]解 计算式为=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x计算结果见下表=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x苯-甲苯溶液的=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x计算数据温度80.184889296100104108110.61.01.0 0=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 6-1附图1与习题6-1附图2所示。[6-6]解 (1) 80.1℃时 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 110.6℃时 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 从计算结果可知,温度高,相对挥发度小。 平均=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x(2) 汽液相平衡方程 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x (3)计算=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x平衡数据,与习题6-1的计算结果接近。[6-10]解(1) 已知馏出液流 精馏段下降液体流量(2) 已知,代入式 求得进料流量 釜液采出量 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x(3) 提馏段下降液体流量 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 提馏段上升蒸气流量 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x或 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x(4) 塔顶操作压力计算=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 苯=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 甲苯 用露点与汽相组成的关系式 计算=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x,已知 解得操作压力 [6-14]。 解 (1)精馏段操作线方程 已知=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x(2) 提馏段操作线方程 已知=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x,计算塔釜汽相回流比=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x。=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x [6-18]解 先将进料组成由质量分数0.4换算为摩尔分数。苯的摩尔质量为78,甲苯的摩尔质量为=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x。=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 已知=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x。相平衡方程=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 精馏段操作线方程 塔釜汽相回流比=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 提馏段操作线方程 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x两操作线交点的横坐标 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x理论板数计算:先交替使用相平衡方程(1)与精馏段操作线方程(2)计算如下=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 第7板为加料板。以下交替使用提馏段操作线方程(3)与相平衡方程(1)计算如下=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 总理论板数为11(包括蒸馏釜),精馏段理论板数为6,第7板为加料板。22解 汽液相平衡方程为 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 已知=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x(1) 冷液进料, 线方程为 由q线方程与相平衡方程解得 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 最小回流比 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x(2) 汽液混合物进料,=dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x q线方程为 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x由q线方裎与相平衡方程解得 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x 最小回流比 =dfrac ({rho )^2-({rho )_(B)}^0}({{rho )_(A)}^2-({P)_(B)}^0} =dfrac ({P)_(A)^0}(P)x
[6-1]解 计算式为

计算结果见下表
苯-甲苯溶液的
计算数据
温度
80.1
84
88
92
96
100
104
108
110.6
1.0
1.0
0
6-1附图1与习题6-1附图2所示。
[6-6]解 (1) 80.1℃时
110.6℃时
从计算结果可知,温度高,相对挥发度小。 平均
(2) 汽液相平衡方程
(3)计算
平衡数据,与习题6-1的计算结果接近。
[6-10]解
(1) 已知馏出液流 精馏段下降液体流量
(2) 已知,代入式 求得进料流量
釜液采出量 
(3) 提馏段下降液体流量
提馏段上升蒸气流量 
或 
(4) 塔顶操作压力计算
苯
甲苯 用露点与汽相组成的关系式
计算
,已知 解得操作压力
[6-14]。 解 (1)精馏段操作线方程 已知

(2) 提馏段操作线方程 已知
,计算塔釜汽相回流比
。
[6-18]解 先将进料组成由质量分数0.4换算为摩尔分数。苯的摩尔质量为78,甲苯的摩尔质量为
。
已知
。
相平衡方程
精馏段操作线方程
塔釜汽相回流比
提馏段操作线方程

两操作线交点的横坐标

理论板数计算:先交替使用相平衡方程(1)与精馏段操作线方程(2)计算如下
第7板为加料板。
以下交替使用提馏段操作线方程(3)与相平衡方程(1)计算如下
总理论板数为11(包括蒸馏釜),精馏段理论板数为6,第7板为加料板。
22解 汽液相平衡方程为
已知
(1) 冷液进料, 线方程为
由q线方程与相平衡方程解得
最小回流比 
(2) 汽液混合物进料,
q线方程为

由q线方裎与相平衡方程解得
最小回流比 
题目解答
答案
解 用试差法计算如下。相平衡方程
(1)
的计算 假设
精馏段操作线方程
两操作线交点的横坐标为 
用相平衡方程(1)与精馏段操作线方程(2)计算如下
从计算的
可知,所假设的
偏大,再假设小一点的
,重新计算。将3次假设的
与
的数值列于表中,并在习题6-24附图1上绘成一条曲线,从曲线上可知
,故所求的
。
计算次数 | 第一次 | 第二次 | 第三次 |
假设 | 0.97 | 0.96 | 0.95 |
-0.071 | -0.0256 | 0.007 |


习题6-24附图1
习题6-24附表1
(2)
的计算
时,两操作线交点的纵坐标为 
设
塔釜汽相回流比
提馏段操作线方程
用相平衡方程(1)与提馏段操作线方程(3),从
开始逐板计算如下
从计算结果可知,所假设的
偏大,重新假设小一点的
,进行计算。将3次假设的
与
的数值列于表中,并在习题6-24附图2中绘出一条直线。用第二次与第三次的计算结果进行比例内插,即
计算次数 | 第一次 | 第二次 | 第三次 |
假设 | 0.05 | 0.035 | 0.025 |
0.0319 | 0.0111 | -0.0026 |
求得
习题6-24附
表2
习题6-24附图2