大型甲苯歧化与烷基转移技术的实践与思考

在对二甲苯产品对外依存度、国内市场需求持续增长和装置生产成本竞争等因素影响下，我国新建对二甲苯生产装置的市场欲望强烈，单装置生产规模不断突破。作为对二甲苯联合装置组成部分的甲苯歧化与烷基转移装置处理量不断增加，单套规模已达300万吨/年，大型化问题不断显现。本文针对不同规模的甲苯歧化与烷基转移装置进行了比较，分析和探讨了300万吨/年或以上规模的装置在大型化过程中面临的关键设备放大、工艺优化节能等问题，提出了单元设备强化、采用甲苯和碳九重芳烃分开处理的组合工艺技术、采用新节能工艺降低能耗等装置优化策略。相关思路的实现有利于解决甲苯歧化与烷基转移装置的大型化问题，使技术大型化的同时，技术竞争力得到同步提升。

Practice and reflection of large capacity toluene disproportionation and transalkylation plant

Due to the para-xylene import dependency,sustained growth in market demand and cost competition of production,it has been desired to construct new para-xylene complex plants,and increase the capacity of single train plant. As a part of the para-xylene plant,the capacity of toluene disproportionation and transalkylation unit also increases continuously. The largest single train has reached 3Mt/a which brought up the problem of large scale. Analyses and investigation were made on the problems in designing toluene disproportionation and transalkylation plant with capacity above 3Mt/a. Strategies, such as equipment intensification,process combination,energy saving etc, were proposed. Those strategies could enhance the competitiveness of toluene disproportionation and transalkylation plant.