共查询到19条相似文献,搜索用时 109 毫秒
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塑料包装废弃物的处理方法基本上可分为填埋、焚烧及回收再生利用。填埋是把垃圾作为废物处理,对垃圾资源的利用率低,不符合国家可持续发展战略。焚烧法可将不能再次利用的混杂塑料在焚烧炉中焚化,由其产生的大量热量可再次充分利用。但焚烧的过程中会产生大量的有害气体,对环境及人体造成危害。回收再生利用包括机械再生利用和化学再生利用。机械再生利用包括直接再生利用及改性再生利用;化学再生利用主要有热分解和化学分解两类。塑料再生利用是国家解决资源短缺的一个重大战略问题,我国废塑料回收利用前景看好。 相似文献
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废旧塑料回收利用的进展 总被引:1,自引:0,他引:1
随着塑料消耗量的逐年增长,废旧塑料的回收利用问题已成为急待解决的一大社会问题和科研课题。本文论述了PE、PP、PVC、PS、PU、难分离的混合塑料和可生物降解或光降解的自灭型塑料等的回收利用研究的进展和方向,指出对聚烯烃类废料主要是与新树脂共混;对PVC废料一般是加入光、热稳定剂,以改善再生制品的性能;对PU和丙烯酸酯类废料是使其降解为单体或低聚物后,用作粘合剂或再聚合;而对难分离的混合废料则常采用熔融共混的方法。 相似文献
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基于机械物理法对热固性废塑料回收降解工艺进行了数值模拟,建立了废旧热固性塑料回收再生试验系统的试验模型,确定了该系统的功能要求。根据分析结果,完成了刀具和机械等结构部分的设计环节,并且进行了整体工艺流程的模拟运算,从而进一步优化工艺流程、参数指标及机械结构。结果表明:通过再生实验专机和机械物理法再资源化实验系统的设计和优化,使机械力活化再生及微细粉碎效果得到增强,大幅提高了废弃塑料的回收降解效率,并且使再生塑料制品的力学性能得到改善。 相似文献
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介绍了2008年我国废塑料再生利用行业的发展状况,包括废塑料的主要来源、废塑料的价格走势、回收量、进口量、国内再生塑料的消费量,分析了进口废塑料的现状及需求情况;同时还指出了废塑料行业存在的主要问题,并对今后的发展提出了一些建议。 相似文献
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生物转化过程具有条件温和、过程绿色、产品高值等优势,是未来废弃物高值化利用的重要途径。塑料是人工合成的有机高分子材料,已作为基础材料融入人类生活的方方面面。而海量剧增的废弃塑料已造成严重的环境污染与资源浪费。由于废弃塑料组分复杂、降解能垒高、胁迫因子多、回收经济性差,单一的生物技术尚无法对其进行即时处理,因此,基于学科交叉与过程集成,综合利用多种废塑料回收技术,建立多元化、个性化、交叉化的塑料回收新路线成为提升我国废弃塑料资源回收与利用水平、发展循环经济的重要途径。本文以生物技术为核心,综述了目前生物-物理、生物-化学以及生物-信息等技术交叉在塑料废弃物回收方面的研究进展,并针对性地分析了学科交叉研究中存在的瓶颈,探讨了未来亟需攻克的技术难点,以期为废塑料的高效回收利用提供新的思路和理论指导。 相似文献
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The most promising representative of biodegradable plastics in packaging applications is polylactide (PLA). Despite this, there is only a small market of PLA in Europe. Reasons for that are the high price of PLA raw material and the lack of knowledge of the behavior in packaging applications. It has a number of peculiarities so producers of plastics packaging hesitate to use it. Like other polyesters, it can degrade at increased temperatures in the presence of moisture by hydrolysis whereby it loses its physical and chemical properties. In all production processes, production waste is generated (i.e., stamping grids or edge trim). In most cases, this waste is used. It is not known in detail, how an internal recycling process will influence the final product properties. One problem is hydrolysis by which the production waste is partially degraded. Target of this study is to analyze the recycling process of PLA within the context of necessary process adaptions and the effects upon ecological efficiency. Films for packaging containing multiple types and amounts of production waste will be produced by extrusion and tested concerning their mechanical properties. The analysis of the recycling behavior showed that internal PLA production waste is well suitable for recycling. The influence of the recycling on the molecular weight is negligible. The effect on the viscosity and thus on the extrusion process is higher. Packaging relevant properties like mechanical or optical properties are hardly influenced. Especially recycling with a recycling quota of up to 50% has an insignificant effect on the film properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41532. 相似文献
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Feedstock Recycling and Energy Recovery from Plastics Waste. The disposal concept of the plastics industry comprises the following four steps: prevention/reduction, recycling of material (mechanical recycling, feedstock recycling), energy recovery and dumping. Feedstock recycling or chemical recycling stands for the chemical conversion of polymer materials with reduction of macromolecular structure to low-molecular raw materials. The combustion of plastics waste uses the high calorific value of plastics for energy recovery. This paper describes some of the processes for feedstock recycling and for energy recovery from plastics waste. 相似文献
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超临界水在降解废弃物及资源化中的应用 总被引:3,自引:0,他引:3
综述了超临界水的特性及其在降解废旧塑料、橡胶、纤维素等废弃物及资源化中的应用现状。与传统热分解方法相比,超临界水可实现对高分子废弃物的快速、有效分解,通过分解反应条件的控制,可以控制产物组成,是一种很有前途的废弃物资源化技术。 相似文献
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Michael Zeller Niklas Netsch Frank Richter Hans Leibold Dieter Stapf 《化学,工程师,技术》2021,93(11):1763-1770
Chemical recycling of plastic wastes can be a useful complement to mechanical recycling to achieve the required plastics recycling rates and to establish a circular economy that is climate neutral and resource-efficient. Different mixed plastic wastes that are subject to future recycling efforts are studied under uniform conditions of intermediate pyrolysis characterized by a medium heating rate and pyrolysis temperature. Product distributions and selected product properties are determined, and process mass and energy balances are derived. Product yields and compositions are highly dependent on the waste pyrolyzed. The results show that pyrolysis is a suitable process to recover chemical feedstock from various complex mixed plastic wastes. 相似文献
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塑料由于材质轻、化学性质稳定、成本低、耐磨性及耐腐蚀性好等优点被广泛应用于工程建设、食品安全、交通运输以及医疗等领域,如果处理不当会对环境造成严重的污染,废塑料污染防治已成为全球关注的环境问题。目前处理废旧塑料的常用方法有风选法、浮选法、静电分离法和光选法等,摩擦电选作为一种新型干式分选方法越来越受到研究者们的重视,其具有工艺简单、污染小、投资少、成本低等优点。本工作针对废旧塑料的分选回收利用,详细介绍了摩擦电选的荷电机理、影响因素、荷电装置和分选设备的研究现状,指出了目前通过摩擦电选回收废旧塑料的技术问题,并对摩擦电选技术未来的发展趋势和应用进行了展望。 相似文献