废弃PET瓶的回收利用

本文简要地介绍了当前已工业化的二种PET废弃瓶的回收利用方法。分析了回收造粒法的主要优点并详细地介绍了废弃PET瓶回收造粒的工艺过程，对于废弃PET瓶的回收造粒的实际应用，具有一定的指导作用。所介绍的废弃PET瓶的回收造粒法，原则上也适用于其它废弃PET制品的回收利用。     

塑料包装废弃物的化学回收技术研究进展

目的 以聚烯烃和聚对苯二甲酸乙二醇酯(PET)为研究对象综述近5年来塑料包装废弃物的化学回收技术,以期为塑料包装废弃物的资源化技术发展趋势提供参考。方法 通过收集与整理相关文献,阐述聚烯烃类以及PET包装废弃物的化学回收方法、常用催化剂、反应装置等,分析催化剂、反应装置、反应温度等条件对产物收率、成分的影响。结论 未来短期内柔性包装材料仍然会以聚烯烃、聚酯等传统石油基材料为主。化学回收是废塑料资源化的一种重要手段,传统催化剂的改良、新型催化剂的开发以及反应装置的优化将是该领域未来的研究重点。     

废弃热固性酚醛树脂回收技术的研究进展

对废弃热固性酚醛树脂的物理回收和化学回收等方法的研究发展进行了综述。主要介绍了物理回收法中的填料法和增强材料法以及化学回收法中的热裂解,催化加氢裂解和溶液分解法等,并对各种方法现存的问题和发展前景进行分析。物理回收法在实际生产应用中较为广泛,而化学回收法也具有广阔的发展前景。     

全球PET瓶循环设计达成一致

<正>PET循环设计规范(标准)的目的是鼓励PET瓶设计师、加工企业和用户能在开发新产品的阶段,将一定准则考虑在内,从而促进PET物理循环的发展。物理循环是重新将废弃材料熔融、变形,从而生成全新再生产品的过程,但不改变所处理材料的化学结构。PET瓶循环设计规范的主要准则包括避免在PET瓶上使用阻碍PET循环流程和降低再生PET质量的材     

基于循环经济概念下的废弃电路板的再利用

运用循环经济原理,讨论了废弃电路板回收利用的必要性和可行性,并对现有废弃电路板资源化技术进行了分析比较,得出机械-物理处理法是回收利用电路板的最佳选择.针对国外废弃电路板的机械回收利用现状,提出了在国内开展废弃电路板资源化、无害化处理研究的一些建议.     

废弃印刷线路板中报废电子元器件的回收处理——以线绕电阻器为例

采用机械破碎、空气分选和磁性吸附等多种物理方式回收处理废弃印刷线路板技术中，其核心的目标是实现线路板上各种材料分门别类的分别回收，以实现其再利用的价值。作为废弃印刷线路板回收处理中金属材料主要来源的电子元器件的回收处理技术是获得高价值回收材料的关键。本文籽对印刷线路板中报废电子元器件的回收处理技术做一介绍，并提出用量较大、回收价值较高的线绕电阻器的回收处理技术。     

废弃聚酯醇解液中乙二醇回收工艺的研究

采用乙二醇降解废弃聚酯(PET)并对降解液中过量的乙二醇进行回收。在降解的不同时期,采用常压蒸馏、减压蒸馏和旋蒸的方法回收乙二醇,并通过红外光谱(FT-IR)、质谱(MS)、羟值和平均分子量对回收产物进行表征。结果表明:回收产物主要成分是聚乙二醇和乙二醇,平均分子量为361.28g/mol,其中聚乙二醇占97.17%,聚合度n为8,乙二醇占2.83%,且旋蒸法回收的产率最高,占降解过程中乙二醇投入量的61.08%。     

废弃PET的化学降解与回收研究

论述了废弃PET的多种回收方式,其中,化学回收是最主要的和有效的方法之一.化学回收方法不仅可以部分地解决固体废弃物的环境污染问题,而且有助于减少石油消耗,发展循环经济,意义重大.     

浅析硬质聚氨酯泡沫塑料的处理及回收利用

硬质聚氨酯泡沫塑料在工业领域的应用越来越广泛,同时大量的聚氨酯废弃物也需要回收利用。本文基于环保的理念,介绍了硬质废旧聚氨酯泡沫塑料的处理及回收方法,主要包括粉碎回收、物理回收、化学回收、焚烧等处理方法的技术原理,以及国内外的发展和应用现状。     

醇解废弃软质聚氨酯泡沫及其应用

废弃聚酯的回收利用已成为当前聚氨酯工业发展的热点研究课题之一。以废弃软质聚氨酯泡沫和乙二醇为主要原料生产聚醚多元醇,回收了乙二醇,同时进行了小试实验降解。产物采用傅里叶变换红外光谱仪进行表征。最后对降解产物的应用进行了讨论,研究表明,利用废弃聚氨酯降解产物作为环氧树脂固化剂符合一般固化剂的要求,固化效果良好。     

农药包装废弃物的处理现状及对策研究

目的 破解农药包装废弃物污染难题，推进农药包装废弃物治理工作。方法 采用文献调查法总结农药包装废弃物的主要处理方式，介绍当前国内外农药包装废弃物的处理现状、主要技术和最新研究进展，分析当前农药包装废弃物处理中存在的主要问题，并给出推动农药包装废弃物回收的对策建议。结果 农药包装废弃物回收的主要问题有:回收意识淡薄、资金投入不足、监管手段有限、处理技术落后。推动农药包装废弃物回收的有效策略:落实主体责任、加大资金投入、变革监管模式、创新回收技术。结论 我国农药包装废弃物污染治理的整体效果依旧欠佳，其回收管理工作必须加以重视。     

包装废聚对苯二甲酸乙二醇酯发泡及其应用研究进展

目的 为包装废聚对苯二甲酸乙二醇酯（PET）的回收和高值转化提供有效参考和依据。方法 通过梳理废PET来源,对比分析不同PET发泡工艺方法及其利弊,分析不同发泡剂的发泡效果,并研究PET的发泡改性途径,进而总结废PET发泡后的应用领域和发泡工艺的发展趋势。结果 近年来废PET发泡材料的研究已取得很大进展,但发泡材料的性能优化仍需进一步探究。结论 大量相关文献证明了利用包装废PET制备发泡材料的可行性,废PET发泡材料的研发符合循环发展的理念,这为废PET的回收和高值转化提供了更多的有效途径,具有广阔的发展前景。     

探究聚氨酯废弃软泡的资源化利用技术(上)

软质聚氨酯泡沫塑料废旧物的回收利用无疑对环境保护和资源利用是有利的,由于聚氨酯的用量较大,而近期原料价格居高不下,其废弃物回收资源化利用市场前景看好。针对废旧聚氨酯软泡塑料的循环利用形势所迫,分别论述了废旧聚氨酯软泡塑料的物理回收利用技术;废旧聚氨酯软泡塑料的化学回收利用技术;废旧聚氨酯软泡回收利用的粘结加压成型和挤出成型技术,以及废旧聚氨酯软泡回收利用热解法制作填料技术等的工艺特点、加工方法,同时指出其社会效益、经济效益和市场前景。     

Orange peel ash coated Fe3O4 nanoparticles as a magnetically retrievable catalyst for glycolysis and methanolysis of PET waste

Chemical recycling of PET offers the process of recovering virgin grade raw materials that can be reprocessed to produce an intact polymeric material or other valuable products. In the current study, we investigate the advantages of exercising biowaste derived orange peel ash (OPA) magnetic nano-catalyst, OPA@Fe₃O₄ as a green and reusable heterogeneous solid catalyst for glycolytic and methanolytic degradation of PET waste. The composition and physical features of the prepared catalyst were studied and analyzed using various techniques. Under the optimized condition, the catalyst was able to obtain an excellent bis(2-hydroxyethyl) terephthalate (BHET) and dimethyl terephthalate (DMT) yield with 100% PET conversion. Moreover, the catalyst was able to be recycled for ten consecutive runs for both processes without a significant reduction in the yield of the reaction, addressing the possible implementation of the catalyst for industrial purposes.     

Review of technologies for oil and gas produced water treatment

Produced water is the largest waste stream generated in oil and gas industries. It is a mixture of different organic and inorganic compounds. Due to the increasing volume of waste all over the world in the current decade, the outcome and effect of discharging produced water on the environment has lately become a significant issue of environmental concern. Produced water is conventionally treated through different physical, chemical, and biological methods. In offshore platforms because of space constraints, compact physical and chemical systems are used. However, current technologies cannot remove small-suspended oil particles and dissolved elements. Besides, many chemical treatments, whose initial and/or running cost are high and produce hazardous sludge. In onshore facilities, biological pretreatment of oily wastewater can be a cost-effective and environmental friendly method. As high salt concentration and variations of influent characteristics have direct influence on the turbidity of the effluent, it is appropriate to incorporate a physical treatment, e.g., membrane to refine the final effluent. For these reasons, major research efforts in the future could focus on the optimization of current technologies and use of combined physico-chemical and/or biological treatment of produced water in order to comply with reuse and discharge limits.     

聚合物基碳纤维复合材料废弃物的几种处理方法分析

从环保和可持续发展角度出发,并结合我国碳纤维(CF)生产与使用实际情况,对聚合物基碳纤维复合材料(CFRP)废弃物处理必要性作了较为详尽的阐述。根据CFRP废弃物种类,提出了机械材料再循环法、材料再循环与能量回收法、能量回收焚烧法三种可行处理方法,并从处理费用、环境影响、替代用途三方面对多种处理方案进行了合理评估。综合考虑处理环境影响、经济效益及替代物使用性能等因素,材料再循环与能量回收法为处理CFRP废弃物最合适的方法。此外,为推进其后期处理工作的顺利进行,还从内部、外部因素两方面提出相关建议。     

Plasma vitrification and re-use of non-combustible fiber reinforced plastic, gill net and waste glass

Fiber reinforced plastic (FRP) composite material has widespread use in general tank, special chemical tank and body of yacht, etc. The purpose of this study is directed towards the volume reduction of non-combustible FRP by thermal plasma and recycling of vitrified slag with specific procedures. In this study, we have employed three main wastes such as, FRP, gill net and waste glass. The thermal molten process was applied to treat vitrified slag at high temperatures whereas in the post-heat treatment vitrified slags were mixed with specific additive and ground into powder form and then heat treated at high temperatures. With a two-stage heat treatment, the treated sample was generated into four crystalline phases, cristobalite, albite, anorthite and wollastonite. Fine and relatively high dense structures with desirable properties were obtained for samples treated by the two-stage heating treatment. Good physical and mechanical properties were achieved after heat treatment, and this study reveals that our results could be comparable with the commercial products.     

Assessment of the performance of different compost models to manage urban household organic solid wastes

The environmental, cultural, socio-economic and political conditions of each community greatly affect the municipality’s effort and decision-making in managing household wastes. Composting at home can be used as a sound method of SWM, can manage the waste at source itself thereby can increase their recycling. And vermicomposting is a viable and completely feasible option at household level, provided it is acceptable to family members to handle the worms and to remove worm-casts subsequently. In this regard, the present paper gives a methodological framework for assessing the management of urban household organic wastes using different compost models to influence the actual efficiency and effectiveness of a municipality’s collection and management services. The current study also deals with the challenges of solid waste management with a focus on the segregation of compostable wastes from the non-compostable ones and their composting, recycling or disposal. The non-compostable wastes can be left for recycling and re-use by the concerned authorities. The composting behavior and the efficiency of different compost models have been dealt with, and it is concluded that vermicomposting model is the best option. Urban residents can be educated to vermicompost not only their entire kitchen wastes but also garden wastes to reduce the burden on the municipal councils.     

Industrial waste recycling strategies optimization problem: mixed integer programming model and heuristics

Manufacturers have a legal accountability to deal with industrial waste generated from their production processes in order to avoid pollution. Along with advances in waste recovery techniques, manufacturers may adopt various recycling strategies in dealing with industrial waste. With reuse strategies and technologies, byproducts or wastes will be returned to production processes in the iron and steel industry, and some waste can be recycled back to base material for reuse in other industries. This article focuses on a recovery strategies optimization problem for a typical class of industrial waste recycling process in order to maximize profit. There are multiple strategies for waste recycling available to generate multiple byproducts; these byproducts are then further transformed into several types of chemical products via different production patterns. A mixed integer programming model is developed to determine which recycling strategy and which production pattern should be selected with what quantity of chemical products corresponding to this strategy and pattern in order to yield maximum marginal profits. The sales profits of chemical products and the set-up costs of these strategies, patterns and operation costs of production are considered. A simulated annealing (SA) based heuristic algorithm is developed to solve the problem. Finally, an experiment is designed to verify the effectiveness and feasibility of the proposed method. By comparing a single strategy to multiple strategies in an example, it is shown that the total sales profit of chemical products can be increased by around 25% through the simultaneous use of multiple strategies. This illustrates the superiority of combinatorial multiple strategies. Furthermore, the effects of the model parameters on profit are discussed to help manufacturers organize their waste recycling network.