毕业设计--年产3200吨乳酸工厂提取车间设计.doc

摘　　要

乳酸是世界上应用广泛的三大有机酸之一。目前生产乳酸主要采取的方法有传统发酵工艺以及固定化微生物法、电渗析连续发酵法、萃取发酵法、膜法发酵法、吸附发酵法、同时糖化发酵法等新工艺，在工业生产中多采用微生物发酵法生产L-乳酸。乳酸的提取精制是乳酸生产中非常重要的步骤，工业生产中常用的乳酸提取工艺主要有：钙盐法、锌盐法、离子交换法、溶剂萃取法和电渗析法等。本设计采用德式乳杆菌为菌种，以大米为主要原料，麸皮为辅助原料经糖化发酵并行式来生产乳酸。在发酵时加入CaCO3作为乳酸中和剂和发酵液稳定剂，得到的发酵液经预处理→浓缩→冷却结晶→洗晶→离心分离→乳酸钙结晶→溶晶→酸解→过滤→脱色等一系列步骤得到粗乳酸；粗乳酸先经浓缩再经离子交换法（先通过732阳离子交换柱再通过331阴离子交换柱）得到纯乳酸。根据上述工艺流程，设计出合理的工艺流程图，通过对乳酸生产平衡、设备平衡和能量平衡等的计算，选取相应设备，设计出设备结构和布置图以及全厂平面布置图。

关键词：并行发酵　乳酸提取车间　工厂设计

Abstract

Lactic acid is one of the three organic acids which widely used in the world.Now the main approach to produce lactic acid include:the traditional fermentation process and immobilized microorganisms,continuous electrodialysis fermentation, extraction　fermentation,membrane fermentation,adsorption fermentation,law saccharification and fermentation technology ect.these new process．Microbial fermentation is the process which most widely used in industrial production to produce L-lactic acid.Extraction of lactic acid production is refined very important step;some processes like:calcium method,zinc salts,ion exchange,solvent extraction and electrodialysis law which are normally used in industrial production of lactic acid;The design used the German Lactobacillusfor strains and rice as the main raw materials,wheat branas auxiliary raw materials and then for parallel saccharification and fermentation to produce lactic acid.The CaCO3 is used as lactic acid neutralizer and stabilizer fermentation broth in the fermentation. The fermentation broth obtained from the fermentation must be treatby these step to be crude lacticby:the pretreatment of the fermentation broth→condense the broth→cooling crystallization of concentrated wash crystal→wash the crystal→centrifuge dissolved→crystallize the calcium lactate into crystal→dissolve it with water→dissolve it with acid→filter it→decolor it ect;crude lactic acid concentration from the first used the via ion exchange(first path through the 732 cation exchange column and then through the 331 anion-exchange column)to be pure lactic acid.Design process flow chart a reasonable on the based of above process.Select the appropriate equipment,calculation the balance on the lactic acid production,equipment and energy,then design the structure and layout of equipment and factory floor plan at last.

Key words: Parallel fermentation  The workshop for extracted lactate  The factory design

目    录

摘要 i

Abstract ii

1  绪论 1

1.1  乳酸的概况 1

1.1.1  乳酸的性质和用途 1

1.1.2  乳酸的质量检验与储存 3

1.2  乳酸的生产技术 3

1.2.1 发酵法 3

1.2.2 化学合成法 4

1.2.3 乳酸生产新技术 5

1.2.4 乳酸的提取和精制技术 6

2  生产工艺 7

2.1  发酵工艺 7

2.1.1 发酵工艺流程及特点 7

2.1.2 发酵工艺条件 7

2.1.3 发酵工艺操作要点及注意事项 8

2.2  提取精制工艺 10

2.2.1 提取工艺流程及特点 10

2.2.2 提取工艺条件 10

2.2.3 提取工艺操作要点及注意事项 11

3 工艺计算及设备选型 14

3.1 发酵工段 15

3.1.1 生产平衡计算 15

3.1.2 设备平衡计算及选型 15

3.2  提取工段 17

3.2.1 生产平衡计算 17

3.2.2 设备平衡计算及选型 18

3.3  水平衡及能量平衡计算 20

3.3.1 水平衡计算 20

3.3.2 能量平衡计算 20

4 车间布置设计 22

4.1设计依据 22

4.2车间布置（厂房平面布置） 22

4.2.1车间布置设计原则 22

4.2.2车间平面布置 23

4.2.3车间立面布置 23

4.2.4设备布置 23

结 论 24

致谢 25

参考文献 26

附录 28