PTA装置中CTA料仓排气处理方法浅析

Treatment of CTA silo discharge gas of PTA plant

探讨了精对苯二甲酸(PTA)装置中粗对苯二甲酸(CTA)料仓排气的处理方法,比较了过滤-水喷淋、水喷淋-旋风分离、过滤-碱喷淋和水喷淋-碱喷淋4种方法的优缺点。结果表明:过滤-水喷淋法和水喷淋-旋风分离法可以回收除对甲基苯甲酸以外的固体颗粒99.8%,过滤-碱喷淋法和水喷淋-碱喷淋法可以将所有酸性物质100%捕集;过滤-水喷淋法的能耗最低为0.84 MJ/t(PTA),过滤-碱喷淋法和水喷淋-碱喷淋法的能耗最高为2.94 MJ/t(PTA);过滤-碱喷淋法和水喷淋-碱喷淋法需消耗一定量的NaOH,但反应产物可以作为副产品出售;4种方法均能将排气处理达标,综合考虑实际操作的稳定性及环保要求,选择过滤-碱喷淋法较理想。

The treatment techniques of crude terephthalic acid （CTA） silo discharge gas were discussed for purified terephthalic acid （PTA） plant.The advantages and disadvantages of filtration-water spray,water spray-cyclone separation,filtration-alkali spray and water spray-alkali spray were compared.The results showed that the techniques of fihration-waterspray and water spray-cyclone separation could recover 99.8% solid particles except p-toluic acid; filtration-alkali spray and water spray-alkali spray could collect 100% acidic material; filtration-waterspray had the lowest energy consumption of 0.84 MJ/t（PTA）,filtration-alkali spray and water spray-alkali spray had the highest energy consumption of 2.94 MJ/t（PTA） ; filtration-alkali spray and water spray-alkali spray needed to consume a certain amount of NaOH,but the reaction products could be sold as by-products;these four treatment techniques enabled the discharge gas to meet the standards,and filtration-alkali spray was proposed to be the best technique for a comprehensive consideration of the practical operation stability and the environment protection requirements.