塑料食品包装对环境的影响及对策探讨

对我国当前包装食品所用塑料的形式、品种和特性做以介绍,并对其中几种常见产品(如塑料袋、一次性饭盒、保鲜膜)的成份、使用情况、毒性及对环境的污染情况进行了分析与探讨。在此基础上,提出了一些合理建议,如减少塑料食品包装的使用,加强对塑料的再生利用,寻找和开发更环保、经济的材料作为塑料替代品等,希望能够尽量减少或避免塑料食品包装对人体和环境的危害。     

改性聚乙烯电机塑料外风扇的开发应用与环境试验

通过改性高低压聚乙烯材料电机塑料外风扇的开发应用与环境试验,为塑料风扇在Y160以下电机的普及应用取得了试验依据,使电机行业获得较大的经济效益.并为开发新品种塑料风扇在Y180以上电机的应用打下了基础.     

企业介绍

北京大正伟业塑料助剂有限公司是集科研、开发、生产、加工、贸易为一体的实体企业。总公司下属有快餐盒分公司和环保设备开发分公司。本公司是国内生产塑料填充改性、降解材料的专业公司,公司以独特的科学配方,先进的生产设备和检测设备,最严密的质量管理体系,形成年产24000吨各种改性材料的生产能力,产品质量达到和超过国内外同行业先进水平,符合 QB1126—91标准。本公司的主要产品:     

环境协调型塑料研究技术途径

本文综述了塑料减量，再使用，回收再利用，稳定化和可降解等五种环境协调型塑料研究技术途径。其中，塑料回收再利用和可降解技术仍是今后需主要发展的研究开发课题。     

上行助“小巨人”显身手

商报讯上海金樱塑料实业有限公司日前宣布:为感谢上海银行在非典期间提供的帮助,企业将其自主开发的吸塑设备命名为“小巨人号”机车。金樱塑料实业有限公司是上海银行“小巨人”培育计划中重点扶持的对象。该企业的主打产品——可降解纳米抗菌塑料餐盒,在当前抗非典的战斗中大显身手,成为     

清洁生产、清洁工艺、绿色技术

微生物法生产生物 可降解塑料 PHB和 PHBHHx1.项目简介 　　可生物降解塑料—聚－β－羟基丁酸酯（ PHB）,也称生物塑料,是用微生物在糖蜜中生长时所积累的一种内聚物。在“九五”攻关过程中。清华大学开发了用废糖蜜为原料生产 PHB的工艺,成本得到很大地降低。 　　生产新型生物塑料—羟基丁酸酯 HB和羟基己酸酯 HHx共聚物 PHBHHx的关键是得到高产的菌种。能合成 PHBHHx的菌种少而又少,“九五”期间通过开发傅立叶红外无损探测技术,清华大学在数千个菌株中筛选得到了一株单胞菌,能满足生产和材料性能的要求。 PHBHHx…     

天然水体中微塑料的来源、分布及毒性效应

天然水体中的微塑料具有粒径小、比表面积大等特点,以及一定的化学毒性,严重威胁着生态环境和人类健康.概述了天然水体中微塑料的来源及分布,重点阐述了天然水体中微塑料的化学毒性及其毒性效应,并对微塑料毒性效应的未来研究方向进行了展望,为进一步促进微塑料的风险评估和科学治理研究提供参考.     

塑料发展环境无害化对策

解决塑料发展与环境问题 ,西欧提出三Ｒ原则 ,即塑料制品的减量（Ｒｅｄｕｃｅ）、再利用（Ｒｅｕｓｅ）和塑料废弃物的回收再利用(Ｒｅｃｙｃｌｅ)。为了更好的实施三Ｒ原则以及减轻一次性塑料废弃物污染环境的问题 ,需研究开发塑料稳定化（ＳｔａｂｌｅＴｅｃｈｎｏｌｏｇｙ）和可降解技术（ＤｅｇｒａｄａｂｌｅＴｅｃｈｎｏｌｏｇｙ）,以提高塑料废弃物的综合治理能力。因此 ,实施三Ｒ原则和应用Ｓ和Ｄ二项技术是当前塑料发展环境无害化主要对策。塑料制品减量减少塑料废弃物的产生 ,应当作为其首选的环境战略。应当推动塑料制品的设计…     

关于塑料废弃物的回收利用与降解塑料的开发和应用

本文扼要论述了当前治理塑料废弃物对环境污染的主要办法：回收利用和降解塑料的开发和应用。阐述了两者的关系和几个概念问题：回收与回收利用;塑料废弃物与一次性塑料废弃物;降解塑料与回收及回收利用。指出,治理塑料废弃物对环境的污染不应采取“一刀切”的办法,而应根据不同情况,区别对待,综合治理。     

土壤环境中微塑料的研究进展和展望

微塑料是国际关注的全球性污染物,土壤是表生环境最大的微塑料储库。土壤微塑料污染及其在土壤中的环境行为对土壤生态系统具有重要影响,目前有关土壤中微塑料的研究相对匮乏。总结了国内外土壤微塑料污染研究现状和污染来源,介绍了土壤中微塑料从采集到检测的流程,对比了不同检测技术的优缺点,并分析了土壤微塑料污染对土壤环境造成的生态风险,展望了未来土壤微塑料的研究方向,以期为深入认识土壤微塑料的污染,统筹土壤微塑料污染治理工作提供理论依据。     

Selective flotation separation of plastics by chemical conditioning with methyl cellulose

The floatability of seven plastics (POM, PVC, PET, PMMA, PC, PS and ABS) in the presence of methyl cellulose (MC) and separation of plastics mixtures were investigated in this paper. It was found that the seven plastics can be separated into three groups by using the wetting agent MC. Group one includes POM and PVC. They are depressed at very low MC concentrations. Group two, including PET, PMMA and PC, has an intermediate floatability. Group three (ABS and PS) has a high floatability. They are almost not depressed within the given MC concentration range. In order to understand the mechanism of selective flotation of plastics and the chemical conditioning process, surface chemical factors, such as wettability of plastics and surface tension of flotation medium, and gravity factors, such as particle density and shape, were studied. It was found that the depressing effect of MC on plastics is ascribed mainly to its adsorption on the plastics surfaces. The MC molecules absorbed on plastics expose some of their polar groups oriented towards the aqueous phase, hence making the plastics surfaces hydrophilic. In addition, flotation selectivity for the plastics is dominated not only by wettability of plastics, but also by particle size, density and shape.     

胜利油田的油泥沙现状及处理工艺探讨

采油生产中的油泥（沙）是胜利油田的重要污染源,对含油泥（沙）处理国际上主要采用加碱、注热水、离心分离的方法将油、沙分离。含油泥（沙）的处理在国内尚无成熟工艺。目前,主要应采用以下方法：原油浓度低的油泥（沙）和油污土壤,主要采用微生物降解的方法进行处理;对原油浓度高的油泥（沙）和油污土壤主要采用物理化学的方法进行处理。可以预测,开展油泥（沙）处理及回收利用可获得巨大的经济效益和环境效益。     

Mechanical separation-oriented characterization of electronic scrap

The ever-increasing amount of electronic scrap and the steadily-decreasing contents of the precious metals used in electronics, as well as the ever-growing environmental awareness, challenges such conventional precious-metal-oriented recycling techniques as pyrometallurgy. Separation and beneficiation of various materials encountered in electronic scrap might provide a correct solution ahead. In this context, mechanical separation-oriented characterization of electronic scrap was conducted in an attempt to evaluate the amenability of mechanical separation processes. Liberation degrees of various metals from the non-metals, which are crucial for mechanical separation, were analyzed by means of a grain counting approach. It is found that the metallic particles below 2 mm achieve almost complete liberation. Particle shapes were also quantified through an image processing system. The results obtained show that the shapes of the particles, as a result of shredding, turn out to be heterogeneous, thereby complicating mechanical separation processes. In addition, separability of various materials was ascertained by a sink–float analysis. It has been shown that density-based separation techniques shall be viable in separating metals from plastics, light plastics (ABS, PS and PVC, etc.) from glass fiber reinforced resins and aluminum from heavy metals. Specifically, a high quality copper concentrate can be expected by density-based separation techniques. Moreover, FT-IR spectra of plastics pieces from the light fractions after the sink–float testing show that PC scrap primarily contains ABS, PS and PVC plastics with the density range of +1.0–1.5 g/cm³, whereas PCB scrap mainly contains glass fiber reinforced epoxy resins plastics with the density range of +1.5–2.0 g/cm³.     

Assessment of plastic packaging waste: Material origin,methods, properties

The global plastics production has increased annually and a substantial part is used for packaging (in Europe 39%). Most plastic packages are discarded after a relatively short service life and the resulting plastic packaging waste is subsequently landfilled, incinerated or recycled. Laws of several European and Asian countries require that plastic packaging waste collected from households has to be sorted, reprocessed, compounded and reused. These recycling schemes typically produce milled goods of poly(ethylene terephthalate) (PET), poly(ethylene) (PE), isotactic poly(propylene) (PP), mixed plastics, and agglomerates from film material. The present study documents the composition and properties of post-consumer polyolefin recyclates originating from both source separation and mechanical recovery from municipal solid refuse waste (MSRW). The overall composition by Fourier transform-infrared (FT-IR) spectroscopy and differential scanning calorimetry (DSC) were determined and compared with the sorting results of the sorted fractions prior to the reprocessing into milled goods. This study shows that the collection method for the plastic packaging waste has hardly any influence on the final quality of the recyclate; however, the sorting and reprocessing steps influence the final quality of the recyclate. Although the mechanical properties of recyclate are clearly different than those of virgin polymers, changes to the sorting and reprocessing steps can improve the quality.     

膨胀型阻燃聚丙烯材料的耐湿热性能研究

聚丙烯(PP)以其优异的力学性能、密度小、质量轻等特点而广泛用于汽车、家电、建筑等行业.但是聚丙烯容易燃烧,其氧指数只有18左右,且燃烧时还会产生大量熔滴,极易传播火焰,这大大限制了其应用.近年来,膨胀型阻燃剂(IFR)在阻燃PP中的应用受到了人们高度的重视.本文主要介绍膨胀型阻燃剂微胶囊制备及其微胶囊在聚丙烯中阻燃性...     

Phosphorus and nitrogen in rainfall simulation runoff after fresh and composted beef cattle manure application

Fresh beef cattle (Bos taurus) manure has traditionally been applied to cropland in southern Alberta, but there has been an increase in application of composted manure to cropland in this region. However, the quality of runoff under fresh manure (FM) versus composted manure (CM) has not been investigated. Our objective was to compare runoff quality under increasing rates (0, 13, 42, 83 Mg ha(-1) dry wt.) of FM and CM applied for two consecutive years to a clay loam soil cropped to irrigated barley (Hordeum vulgare L.). We determined total phosphorus (TP), particulate phosphorus (PP), dissolved reactive phosphorus (DRP), total nitrogen (TN), NH4-N, and NO3-N concentrations and loads in runoff after one (1999) and two (2000) applications of FM and CM. We found significantly (P < or = 0.05) higher TP, DRP, and NH4-N concentrations, and higher DRP and TN loads under FM than CM after 2 yr of manure application. The TP loads were also higher under FM than CM at the 83 Mg ha(-1) rate in 2000, and DRP loads were higher for FM than CM at this high rate when averaged over both years. Application rate had a significant effect on TP and DRP concentrations in runoff. In addition, the slope values of the regressions between TP and DRP in runoff versus application rate were considerably higher for FM in 2000 than for FM in 1999, and CM in both 1999 and 2000. Significant positive relationships were found for TP and DRP in runoff versus soil Kelowna-extractable P and soil water-extractable P for FM and CM in 2000, indicating that interaction of runoff with the soil controlled the release of P. Total P and DRP were the variables most affected by the treatments. Overall, our study found that application of CM rather than FM to cropland may lower certain forms of P and N in surface runoff, but this is dependent on the interaction with year, application rate, or both.     

废弃泥浆对农作物毒性影响研究

通过采用废弃泥浆对水稻、大麦、和小麦的发芽试验及田间实验,对作物生长发育的几项指标的影响差异进行了研究,结果表明：废弃泥浆对作物毒害效应顺序依次为小麦>大麦>水稻。泥浆中的有毒有机物毒性效应较重金属明显,其次,泥浆的致密性也是影响作物生长的主要原因。     

铁合金电炉烟尘的性质与低温固结研究

本文研究了硅铁电炉布袋除尘收集的烟尘性能，烟尘低温固结球团的性能和工艺方法。研究结果表明，硅铁电炉烟尘中ＳｉＯ２ 约占９０ － ９５ ％ ，其它组分含量较低，有利于进行回收利用。烟尘密度小、粒度细、表面活性差、成球性能差。采用添加粘结剂进行自然养护和低温固结处理，均能获得强度较好的固结球团，能够加入铁合金炉回收利用。     

Mechanical performance of woodfibre–waste plastic composite materials

Plastic products used for packaging are often discarded after a single use resulting in an inexhaustible supply of waste polymeric materials. The stiffness and strength of polymeric materials have been known to improve with the addition of lignocellulosic fibres available in abundance in nature. Hence, composite materials containing natural fibres and waste plastics would result in the reduction of solid wastes and the use of cheap, renewable resources. Composite specimens, consisting of waste plastics obtained from a Kerbside collection (high density polyethylene (HDPE) waste, Janitorial waste, Kerbside waste I and Kerbside waste II) and Pinus radiata woodfibres (medium density fibres (MDF)), have been produced through melt blending and injection moulding. The effects of fibre content, matrix type and interfacial bonding on the tensile and flexural properties of these composite materials have been determined through extensive testing at various conditions. The mechanical properties of these composites at room temperature and humidity depend on the amount of woodfibres, the mechanical properties of the waste plastics used and the presence of a suitable coupling agent. The tensile strengths of MDF/waste plastic composites do not generally change with fibre content except for 40% MDF/HDPE waste and 40% MDF/Kerbside waste II (plus 1% Epolene™) composites, where the tensile strengths increase by about 25% compared to those of the corresponding waste plastics. Flexural strengths of MDF/waste plastic composites increase with the addition of medium density fibres with the exception of MDF/Kerbside waste I composites. The tensile and flexural moduli of MDF/waste plastic composites mostly increase with increasing fibre content.     

钻井泥浆固化处置对地表水环境影响

选取四川省境内比较有代表性的5处井场,通过进行不同水泥固化剂处理效果的对比,包括固化体样品性状对比及固化体浸出液污染因子监测数据对比,分析以水基泥浆为原泥浆的钻井废泥浆固化处理工艺的效果,以及现有常用固化处置对周边地表水环境的影响。