PTA蒸汽管回转干燥机结垢原因分析

通过干燥模拟试验,分析了对苯二甲酸(PTA)生产中蒸汽管回转干燥机结垢的原因,并对垢料成分进行分析,提出了控制结垢的措施。结果表明:对氧化阶段的醋酸母液在循环使用前进行过滤或减压蒸馏,可延缓干燥机结垢;控制干燥前粗对苯二甲酸(CTA)滤饼的含湿量约10%,CTA滤饼中杂质对羧基苯甲醛、对甲基苯甲酸、苯甲酸含量分别为2100～2300,200～250,100～150μg/g,可有效的减少结垢量。

Fouling reasons analysis for PTA steam tube rotary dryer

The fouling reasons of PTA steam tube rotary dryer were analyzed during the production of terephthalic acid(PTA) through drying simulation experiments.The composition of the fouling material was analyzed.The measures to restrain the fouling were proposed.The fouling of the dryer can be restrained through the filtration and vacuum distillation of acetic acid liquor to the oxidation stage prior to recycling.The quantity of fouling material can be efficiently reduced by controlling the moisture content of crude terephthalic acid(CTA) filter cake about 10%before drying and controlling the impurities content of CTA filter cake as followed;2 100 -2 300,200 -250,100 - 150μg/g for 4-carboxybenzaldehyde,p -toluic acid,benzoic acid,respectively.