【作者】 何静；

【导师】 单国荣； 王永如；

【作者基本信息】 浙江大学 ， 化学工程（专业学位）， 2016， 硕士

【摘要】 针对我国高品质铜资源供不应求,废杂铜回收利用率低的现状,利用废电磁线直接保质生产无氧铜杆将是铜资源循环利用的重大突破,漆包线表面聚合物涂层的剥除是废电磁线回收利用的首要步骤,重点在于研究开发适于工业化大规模生产的漆包线脱漆工艺。本论文在分析漆包线漆膜成分、比较各种脱漆方法、研究聚合物降解原理、结合工厂实际情况的前提下,确定利用碱溶液法脱除漆包线表面聚酯涂层,并对该方法的工艺条件进行探究。实验发现NaOH溶液可有效脱除聚酯漆包线漆膜,而且脱漆时间随着NaOH溶液浓度的增加而线性减少,随着脱漆温度的升高而线性减少。此外,脱漆剂具有良好的循环利用性,NaOH溶液经五次循环后脱漆能力没有太大的变化,溶液中累积铜损失量随着循环的进行而增加,剩余溶液随着循环的进行而减少,溶液中剩余NaOH的总量也随着循环的进行而减少,故需要及时对脱漆剂进行补充和回收净化。利用碱溶液法脱漆,漆膜中的聚酯成分没有深度降解,漆膜回收率在60%以上,铜回收率大于98%,铜损失率小于0.02%,满足工业化、清洁化处理的要求。碱溶液法脱除聚酯漆包线表面漆膜主要是依靠NaOH溶液对漆膜主要成分聚酯中酯键的碱性水解,降低了漆膜之间的结合力,从而使漆膜从基材上脱除。论文分别对已成型的聚酯漆包线表面漆膜、未经涂覆的QZ130-1730液体漆和聚己二酸丁二醇酯进行降解实验的探究,确定以聚己二酸丁二醇酯为研究对象,考察NaOH溶液对其的降解情况,分别利用差重法测降解率和凝胶渗透色谱仪检测降解产物及其分子量。实验表明,该聚酯的降解率随着反应时间的延长而线性增加,随着NaOH溶液浓度的增大而线性增加；而且,随着反应时间的延长和NaOH溶液浓度的增加,产物中分子量大的物质逐渐减少,分子量小的物质逐渐增多,降解得越来越深入。类比推测其他成分的聚酯在碱溶液中降解有相似的规律。论文进一步以碱溶液法脱漆实验得出的最优工艺条件为依据设计工艺流程图,根据处理废杂电磁线10000吨／年的生产能力要求和工厂实际情况,对流程图中各设备进行了初步的设计与计算。得出了对设备选择的初步要求,主要包括各设备的容量、尺寸、功率、物料进出量以及设备材质的选择等。最后在宁波金田钢业(集团)股份有限公司进行脱漆实验的中试和工程试验,初步形成了有效分离回收铜线和表面涂层聚合物的绿色环保示范工程试验生产线方案。在工程试验中,先后设计并开发了摇杆式脱漆炉、搅拌式脱漆炉以及具备循环过滤装置的脱漆炉。中试和工程试验表明,在最优工艺条件下利用碱溶液法脱除聚酯漆包线表面漆膜具有工业可行性。脱漆液中铜离子含量低,只有0.01%；有机物过度降解程度低,没有出现碱液随处理时间老化的现象。对原料和能耗初步估算得出,每吨漆包线的碱消耗费用约为20元,加热的能耗费用预计控制在100元/吨。更多还原

【Abstract】 In response to the situation that high quality copper resource is in short supply and the recovery utilization ratio of scrap copper is at low level, using scrap electromagnetic wire to produce oxygen free copper rod directly will be the major breakthrough in the copper resources recycling. Removing the polymer coating from the surface of enameled wire is the first step of electromagnetic wire recycling. The emphasis is on the research and development of paint removing process which is suitable for industrial mass production. Based on the analyzing the coating composition, comparing all kinds of paint removing methods, researching of polymer degradation principle, combination with the practical situation of the factory, the method using alkali solution to remove polyester coating from the surface of enameled wire was determined and the process condition of the method was explored. It could be found from the experiment that the polyester coating can be removed effectively by NaOH solution. Coating removing time decreased linearly with the increase of NaOH solution concentration and with the rising of temperature. Besides, the recycling performance of the paint remover was proved to be very good. The removing ability of NaOH solution didn’t change much after recycled five times. With the increase of cycling times, the cumulative copper loss ratio in solution was increased, the residual solution volume was decreased, and the amount of residual NaOH was decreased. NaOH solution should be supplied and purified in time. Using this method, polyester of paint film didn’t degrade excessively. Film recovery ratio was higher than 60%, copper recovery ratio was higher than 98%, copper loss ratio was lower than 0.02%, those data met the requirements of industrialization and cleansing process.Using alkali solution to remove polyester coating from the surface of enameled wire depends on alkaline hydrolysis of ester bond of the polyester in the coating film. It reduces the bonding force of paint film, so that the paint film can be removed from the copper base. Based on this, the degradation experiments of established polyester film, QZ130-1730 liquid paint and polybutyleneglycol adipate were explored. Using weight difference method to detect the degradation ratio and gel permeation chromatography to detect the degradation products and their molecular weight, polybutyleneglycol adipate was determined to be the research object. The results showed that the polyester degradation ratio was increased linearly with the extension of reaction time and also increased linearly with the increase of NaOH solution concentration. Besides, with the extension of reaction time and the increase of NaOH solution concentration, that of high molecular weight gradually reduce, and that of small molecular weight increases gradually which means the polyester degrade. The degradation of other polyester in the alkali solution follows similar rules by analogy.Based on the optimal process condition, the process flow diagram was designed. Considered the capacity requirements of production line for dealing with scrap electromagnetic wire 10000 tons/year and the actual situation of the factory, the equipment of the process flow diagram were designed and calculated. The preliminary requirements of equipment selection were decided, mainly including the capacity, size, power, materials and delivery quantity.The pilot scale test and engineering test were taken in Ningbo Jintian Copper Co. LTD. Environmental protection demonstrated production line of effectively separating and recycling copper and polymer coating was initially formed. Rocker type paint stripping furnace, stirring type paint stripping furnace and paint stripping furnace with circulative filtration unit were designed and developed in engineering test. Results showed that, the method of using alkali solution to remove the polyester coating from the surface of enameled wire under the optimal process condition was feasible to industrialize. Copper ion in NaOH solution was only 0.01%, at a very low level. Polymer didn’t degrade excessively. The phenomenon of alkali liquor aging didn’t appear. The results of preliminary estimates for raw materials and energy consumption showed that, while dealing with one ton enameled wire, the cost of NaOH was 20 Yuan, and the heating energy cost was expected to control at 100 Yuan.更多还原