真空制盐工艺设计

四川理工学院毕业设计

85kt/a真空制盐工艺设计

学 生：青勇权 学 号：

专 业：化学工程与工艺 班 级：2007.3 指导教师：向群

四川理工学院材料与化学工程系

二O一一年六月

85kt/a真空制盐工艺设计

摘要

制盐工业在国民经济中占有重要的经济地位，是国民经济的重要组成部分，本设计主要是针对中小型企业制盐生产。真空制盐蒸发工序生产，是以卤水为原料采用四效蒸发、平流进料、顺流排盐及外加热强制循环蒸发器制得粗盐。其中采用闪发器，充分利用蒸汽冷凝后的余热，让冷凝水在压差作用下闪发出蒸汽。设计主要进行蒸发器各效物料衡算、热量衡算及设备设计和选型，并绘制带控制点工艺流程图和蒸发器装配图。

关键词：真空；蒸发；四效平流；强制循环；闪发器

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Process Design Of 85kt/a Vacuum Evaporation

Abstract

The salt industry in the national economy has important economic status，is an important part of the national economy，this design is mainly aimed at small and medium enterprise salt production．Evaporation process production device for raw material with brine，by four effect evaporation，PingLiu feeding，downstream row salt and exterior heating made compulsory recycling evaporator buried．Use among them，make full use of flash hair device after steam condensate of waste heat，let the condensate on the pressure difference out under the action of flash steam．Design major evaporator each effect material calculation，heat calculation and equipment design and selection，and draw with flow chart and evaporator assembly points．

Key words：vacuum；evaporation；four effect；PingLiu forced circulation；flash hair device

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目 录

第一章 绪论 ............................................................................................................ 1

1.1 盐的特性 ......................................................................................................... 1 1.2 盐业的发展概况 ............................................................................................. 1

第二章 卤水的蒸发 ............................................................................................. 4

2.1 概述 ................................................................................................................. 4 2.2 蒸发过程的特点 ............................................................................................. 4 2.3 真空制盐工艺流程的选择 ............................................................................. 4

第三章 工艺计算 .................................................................................................. 6

3.1 计算基础数据 ................................................................................................. 6 3.2 总物料衡算 ..................................................................................................... 6 3.3 总物料进料表 ................................................................................................. 7 3.4 热量衡算 ......................................................................................................... 8

3.4.1 参数计算 ............................................................................................ 8 3.4.2 热量衡算过程 .................................................................................. 10 3.4.3 热量衡算结果 .................................................................................. 13 3.4.4 蒸发器热量平衡表 .......................................................................... 15 3.5 迭代计算 ....................................................................................................... 17

3.5.1 重新分配 .......................................................................................... 17 3.5.2 热量衡算过程 .................................................................................. 18 3.5.3 热量衡算结果 .................................................................................. 21 3.5.4 蒸发器热量平衡表 .......................................................................... 23 3.6 各效物料衡算 ............................................................................................... 25

3.6.1 物料衡算结果 .................................................................................. 25 3.6.2 物料衡算平衡表 .............................................................................. 26

第四章 设备设计和选型 ................................................................................. 28

5.1 蒸发器 ........................................................................................................... 28

5.1.1 加热室 .............................................................................................. 28 5.1.2 蒸发室 .............................................................................................. 33 5.2 传热系数的校核 ........................................................................................... 35

5.2.1 I效传热系数的校核 ....................................................................... 35

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5.2.2 II效传热系数的校核 ..................................................................... 37 5.2.3 III效传热系数的校核 ................................................................... 39 5.2.4 IV效传热系数的校核 ..................................................................... 40 5.3 附属设备 ....................................................................................................... 42

5.3.1 循环泵 .............................................................................................. 42 5.3.2 闪发桶和平衡桶 .............................................................................. 42 5.3.3 除沫器 .............................................................................................. 43 5.3.4 支座的设计 ...................................................................................... 44 5.3.5 弯头 .................................................................................................. 45 5.3.6 折流挡板 .......................................................................................... 46 5.4 主要设备一览表 ........................................................................................... 46

第五章 环境保护与安全 ............................................................................... 47

5.1环境保护 ........................................................................................................ 47

5.1.1 真空制盐三废的来源 ...................................................................... 47 5.1.2 三废的治理方法 .............................................................................. 47 5.2蒸发过程安全操作 ........................................................................................ 47

设计评述 .................................................................................................................. 49

参考文献 .................................................................................................................. 50 致 谢 ....................................................................................................................... 51 附 图 ....................................................................................................................... 52

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