超高黏PA 6切片的生产优化改造

Novation and optimization of ultra-high viscosity PA 6 chips production process

针对15 kt/a超高黏PA 6固相聚合装置产品存在黏度不均匀、所制双向拉伸薄膜不易开口,以及装置生产能耗较高等问题,分析了问题产生的原因,并提出了相应的改造措施。结果表明:通过采取在固相缩聚塔底部增加一个分配锥,在切片中添加质量分数为0.5%的复合开口剂,将冷却喷淋系统从循环氮气系统中断开等措施,生产的超高黏PA 6切片相对黏度稳定在4.0±0.1,可萃取物质量分数小于等于0.51%,含水量小于等于400μg/g,达到优等品水平,制备的BOPA薄膜表面光泽度、透明度高,开口性好,力学性能、阻隔性指标均达到国外品牌同等水平;固相聚合装置电耗降至157.5 kW·h,仪表空气消耗降至26 Nm^(3)/h,蒸汽消耗降至0.275 t/h,冷冻水消耗降至35 t/h,能耗下降明显。

The causes of non-uniform product viscosity,difficult opening of biaxial tensile film and high production energy consumption of 15 kt/a ultra-high viscosity PA 6 solid-state polymerization unit were analyzed,and the corresponding transformation measures were put forward.The results showed that by adding a distribution cone at the bottom of solid-phase polycondensation tower,adding a compound opening agent with a mass fraction of 0.5%in chips,and interrupting cooling spray system from circulating nitrogen system,the relative viscosity of the produced ultra-high viscosity PA 6 chips was stable at 4.0±0.1,the mass fraction of extractable matter was less than or equal to 0.51%,and the water content was less than or equal to 400μg/g,reaching the level of excellent products.The prepared BOPA film had high surface gloss and transparency,good opening,and the mechanical properties and barrier indexes had reached the same level of foreign brands;and the energy consumption of the solid-state polymerization unit decreased significantly,including the power consumption down to 157.5 kW·h,the instrument air consumption down to 26 Nm ^(3)/h,the steam consumption down to 0.275 t/h,the chilled water consumption down to 35 t/h.