Modeling method for heterogeneous azeotropic rectification solvent dehydrating tower of industrial purified terephthalic acid (PTA) device

Abstract

The invention relates to a modeling method for a heterogeneous azeotropic rectification solvent dehydrating tower of an industrial purified terephthalic acid (PTA) device. In the method, the vapor-liquid balance experimental data of an acetic acid, n-propyl acetate, water, p-xylene and methyl acetate quinary mixture system are associated and fitted with the binary interaction parameters of the quinary mixture system according to a thermodynamic property model; and according to the process data of the solvent dehydrating tower under the actual device design condition, a heterogeneous azeotropic rectification solvent dehydrating tower model of the industrial PTA device under the design condition is established, the accuracies of the thermodynamic model and parameters thereof of the quinary mixture system in a laboratory and a rectification tower mathematical steady model are verified, key parameters representing the separating property of the solvent dehydrating tower under the actual condition are acquired, the model is corrected and a process mechanism steady model capable of accurately describing the operating characteristics of the solvent dehydrating tower under the actual condition is established.

Description

technical field [0001] The invention relates to a modeling method of a heterogeneous azeotropic distillation solvent dehydration tower, especially a heterogeneous azeotropic distillation solvent dehydration tower using n-propyl acetate as an entrainer in an industrial purified terephthalic acid device modeling method. Background technique [0002] Purified Terephthalic Acid (PTA) is an important chemical raw material widely used in polyester and other chemical production. The production of PTA generally uses p-xylene (PX) as raw material and acetic acid (HAC) as solvent to catalyze and oxidize crude terephthalic acid (TA) at a certain temperature and pressure, and then refine it into high-purity refined paraxylene. Phthalic acid. When PX is oxidized to produce terephthalic acid, acetic acid is used as a solvent, and water (H 2 O) is formed, thus producing an aqueous solution of acetic acid. At the same time, due to the incomplete oxidation reaction and the occurrence of ...

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Problems solved by technology

A small amount of PX accumulates continuously in the tower. When its concentration increases to a certain level, it will inevitably weaken the performance of the tower and affect the effect of azeotropic separation.

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