精对苯二甲酸(PTA)生产技术及工艺流程
摘 要
精对苯二甲酸（PTA） 英文名称：Pure terephthalic acid（PTA)分子
式C6H4（COOH）2 。 是以对二甲苯为原料，液相氧化生成粗对苯二甲酸，再经加氢精制，结晶，分离，干燥，得到精对苯二甲酸。精对苯二甲酸为白色针状结晶或粉末，约在 300℃升华，自燃点680℃。能溶于热乙醇，微溶于水，不溶于乙醚、冰醋酸和氯仿。低毒，易燃。其粉尘与空气形成爆炸性混合物，爆炸极限0.05g/L～12.5g/ L。
精对苯二甲酸是生产聚酯切片、长短涤纶纤维等化纤产品和其它重要化工产品的原料。精对苯二甲酸（PTA）是重要的大宗有机原料之一，其主要用途是生产聚酯纤维(涤纶)、聚酯薄膜和聚酯瓶，广泛用于与化学纤维、轻工、电子、建筑等国民经济的各个方面，与人民生活水平的高低密切相关。
关键词：氧化反应 结晶 高压吸收 常压吸收 分离 干燥 溶剂及催化剂回收 残渣蒸发 溶剂脱水 萃取 常压汽提系统 加氢反应 过滤
I
目 录
摘 要 ······································································································································· I 前 言 ································································································································· - 1 - 第一章精对苯二甲酸的工业概貌 ················································································· - 2 -
1.1 世界精对苯二甲酸工业概貌 ········································································· - 2 - 1.2 我国精对苯二甲酸工业概貌 ········································································· - 3 - 第二章 精对苯二甲酸的上下游产业链 ···································································· - 5 -
2.1 精对苯二甲酸的上游产业·············································································· - 5 - 2.2 精对苯二甲酸的下游产业·············································································· - 5 - 第三章 精对苯二甲酸的性质及其主要用途 ··························································· - 6 -
3.1 精对苯二甲酸的性质 ······················································································ - 6 - 3.1 精对苯二甲酸的主要用途·············································································· - 6 - 第四章 精对苯二甲酸的主要原料 ············································································ - 7 - 第五章 产品方案及规格 ······························································································ - 8 -
5.1 产品方案 ············································································································ - 8 - 5.2 主要产品规格 ··································································································· - 8 - 第六章 精对苯二甲酸的生产工艺技术 ···································································· - 9 -
6.1 国外工艺技术现状 ··························································································· - 9 - 6.2 国内的工艺技术选择 ···················································································· - 10 - 第七章 精对苯二甲酸的工艺流程及操作条件 ····················································· - 11 -
7.1 反应历程简介 ································································································· - 11 -
7.1.1 对二甲苯氧化 ····················································································· - 11 - 7.1.2对苯二甲酸精制 ·················································································· - 12 - 7.2 工艺流程简述 ································································································· - 12 -
7.2.1 空气压缩机 ·························································································· - 12 - 7.2.2 100 单元---母液储存罐 ·································································· - 12 - 7.2.3 200 单元--氧化反应、结晶、高压吸收及常压吸收。 ············ - 13 - 7.2.4 300 单元－－分离、干燥 ································································ - 14 - 7.2.5 400 单元－－溶剂及催化剂回收、残渣蒸发、溶剂脱水、萃取、常压汽提系统。 ······························································································· - 14 - 7.2.6 500 单元—进料配制、反应进料预热、加氢反应、结晶 ······· - 16 - 7.2.7 600 单元—过滤、干燥 ···································································· - 19 - 7.2.8 PTA 产品之储存装袋及出料 ··························································· - 20 -
第八章 精对苯二甲酸生产的关键设备及其特点 ················································ - 22 -
8.1 精对苯二甲酸氧化单元的关键设备——氧化反应器 ···························· - 22 - 8.2 精对苯二甲酸精制单元的关键设备 ·························································· - 22 -
I
第九章 结论 ·················································································································· - 24 - 参考文献 ·························································································································· - 25 - 致 谢 ···················································································································· - 26 -
II
前 言
本项目由精对苯二甲酸（PTA）主生产装置、辅助生产装置和公用工程装置等组成。精对苯二甲酸（PTA）主生产装置：主要包括氧化单元、精制单元和公用设施等，其中：
氧化单元：主要包括空气压缩、进料准备、氧化反应、CTA结晶、CTA过滤、CTA干燥、溶剂回收、催化剂回收残渣处理（CRU）、MA水解、尾气焚烧处、CTA 母液储存系统理等。
精制单元：主要包括浆料制备、加氢反应、PTA结晶、PTA压力过滤、PTA干燥和产品输送、工艺水和母液固体回收、碱系统等。
辅助生产装置：原料及化工料罐区、精对苯二甲酸（PTA）输送、包装及贮存码头输送系统等。
本次主要论述的是精对苯二甲酸装置中氧化单元和精制单元生产技术、工艺流程及一些氧化溶剂的回收、脱水、萃取、尾气干燥、处理等。本装置设计能力为每年产120万吨PTA工程项目是大连市近年来投资最大的内资项目之一，主要生产化纤原料——PTA，是一家实现PTA技术自主开发研究并建造的公司。以对二甲苯为原料，液相氧化生成粗对苯二甲酸，再经加氢精制，结晶，分离，干燥，得到精对苯二甲酸。
- 1 -
第一章精对苯二甲酸的工业概貌
1.1 世界精对苯二甲酸工业概貌
目前，亚洲是全球精对苯二甲酸（PTA）最主要的生产地和需求地，而北美和西欧地区的生产能力远远低于亚洲。世界PTA主要贸易量集中在亚洲地区，2009年进出口量分别占世界总量的71.1％及65.9％；西欧地区则分别占14.6％及20.1%；北美地区分别占5.9％及11.3％。北美及西欧地区是世界PTA主要净出口地区，而亚洲、中南美洲和中东欧是主要净进口地区。从近几年世界PTA的贸易趋势来看，亚洲地区贸易量占世界总贸易量的比例逐年上升，西欧地区略有下滑，而北美地区呈下降的趋势。
目前，世界PTA主要用于生产聚酯，占PTA总消费量的98％以上，而PTT（聚对苯二甲酸丙二醇酯）与PBT（聚对苯二甲酸丁二醇酯）在工业化生产规模较小，目前对PTA的需求量仅约200万吨。
未来几年世界PTA工业仍将快速发展，据预测，2010年世界PTA的需求量将达到4500万吨，其中亚洲3000万吨，占世界的67％；2010年世界PTA产能超过4952万吨/年，新增产能主要来自亚洲的中国、印度、泰国等国家。中东、北美及西欧等地的PTA产能增速相对较缓，新建计划不多。而未来世界PTA消费结构变化不明显，用于生产聚酯的比例仍将超过90％。
表1世界PTA供需状况（万吨） 年份 1993 1994 1995 1996 1997 1998 生产能力 980 1080 1270 1420 1830 2000 生产量 902 1000 1140 1280 1480 1580 消费量 902 1000 1140 1280 1480 1580 开工率/% 92 92 90 90 81 79 - 2 -