由于粗苯酐中所含的蒽醌及其同系物等重组分含量极少，在反应工段中没有对其

由于粗苯酐中所含的蒽醌及其同系物等重组分含量极少，在反应工段中没有对其进行物料的计算，且沸点与苯酐相差很大，极易除去，对产品影响不大，而且粗苯酐中的杂质经过轻组分塔精馏后基本除去，能达到设计要求。所以本次设计对苯酐精馏工段中的重组分塔只作介绍，不作计算。进而在本章中对苯酐精馏工段进行物料衡算时，可以近似认为从轻组分塔塔底提取的苯酐熔液即为产品苯酐(即物流3)。同样的，在本次设计中对精馏塔的设计计算章节也只考虑其中的轻组分塔。

由于粗苯酐中所含的蒽醌及其同系物等重组分含量极少，在反应工段中没有对其进行物料的计算，且沸点与苯酐相差很大，极易除去，对产品影响不大，而且粗苯酐中的杂质经过轻组分塔精馏后基本除去，能达到设计要求。 所以本次设计对苯酐精馏工段中的重组分塔只作介绍，不作计算。 进而在本章中对苯酐精馏工段进行物料衡算时，可以近似认为从轻组分塔塔底提取的苯酐熔液即为产品苯酐(即物流3)。 同样的，在本次设计中对精馏塔的设计计算章节也只考虑其中的轻组分塔。

Because the content of anthraquinone and its homologues in crude phthalic anhydride is very small, there is no calculation of the materials in the reaction section, and the boiling point is very different from that of phthalic anhydride, which is easy to remove and has little impact on the product. Moreover, the impurities in crude phthalic anhydride are basically removed after distillation in light component tower, which can meet the design requirements. Therefore, this design only introduces the recombiner in the rectification section of phthalic anhydride, without calculation. In this chapter, when calculating the material balance of phthalic anhydride distillation section, it can be approximately considered that the phthalic anhydride molten solution extracted from the bottom of the light component tower is the product phthalic anhydride (i.e. logistics 3). Similarly, in this design, only the light component tower is considered in the design and calculation section of distillation tower.<br>