废旧渔网的清洗及高等级再生尼龙渔网粒子的制备

Cleaning of Waste Fishing Nets and Preparation of High-Grade Recycled Nylon Fishing Net Particles

废旧塑料的回收迫在眉睫,特别是海洋废旧塑料中的聚酰胺(PA,尼龙)废旧渔网,现阶段再生PA渔网的粒子异色点多、纯度差,无法满足高端及浅色产品需求。本文研究了磨洗、洗涤剂种类及洗涤剂浓度对再生PA渔网表面杂质去除效果,得出磨洗有利于渔网杂质的去除、十二烷基硫酸钠(K12)对渔网的清洗优于其他洗涤剂等结论。此外,洗涤浓度对废旧渔网清洗效果影响较小。通过简单清洗难以完全分离废旧渔网中的泥沙杂质,需在熔融造粒过程中采用滤网过滤对废旧渔网进行再次除杂提纯。实验表明,100目滤网过滤制备的再生PA渔网粒子不满足高纯度需求,其灰分中存在部分泥沙,而当滤网的过滤精度达300目时,其纯度接近新料PA6 HY2800A,可满足高纯度需求。

The recycling of waste plastics is imminent,especially for the polyamide(PA,nylon)waste fishing nets in marine waste plastics.At present,the particles of regenerated PA fishing nets have many different color points and poor purity,which cannot meet the needs of high-end and light-color products.In this paper,the effects of grinding,detergent types and detergent concentrations on the removal of the impurities on the surface of recycled PA fishing nets were studied.The results show that grinding is beneficial to the removal of impurities in fishing nets,and sodium dodecyl sulfate(K12)is superior to other detergents in cleaning fishing nets.In addition,the washing concentration has little effect on the cleaning effect of waste fishing nets.The sediment impurities in the waste fishing nets are difficult to be completely separated by simple cleaning.It is necessary to purify the waste fishing nets by filter filtration again during the process of melt granulation.Experiments show that the recycled PA fishing net particles prepared by 100 mesh filter do not meet the high-level requirements,and there are some sediments in their ashes.When the filtration accuracy of the filter reaches 300 mesh,the purity of the recycled PA fishing net particles is close to the level of new material(PA6 HY2800A),which can meet the high-level requirements.