国内降解塑料的生产现状及发展中应注意的问题

通过对几家生产企业典型降解塑料产品及产品降解性的分析 ,提出了在研究开发和推广应用降解塑料时应综合考虑生产成本及产品降解性两个重要因素。     

国内降解塑料的生态现状及发展中应注意的问题

通过对几家生产企业典型降解塑料产品及产品降解性的分析,提出了在研究开发和推广应用降解塑料时应综合考虚生产成本及产品降解性两个重要因素。     

我国率先用印染污泥制降解塑料

<正>近日从浙江省现代纺织工业研究院获悉,由该院与绍兴印染企业联合开发的印染污泥综合利用核心技术近期取得突破性进展:以纺织印染污泥为原料生产的降解塑料制品,日前经德国Tu V机构检测证明符合相关环保标准。"污泥降解塑料是国际前沿课题,许多发达国家都在研究,但尚未取得突破。"浙江省现代纺织工业研究院院长胡克勤说,"我们开发的技术工艺从根本上突破了污泥拥有塑料特性并实现降解、污泥     

悬浮填料在废水生物处理中的应用进展

综述了悬浮填料及反应性悬浮填料在废水生物处理中的应用。在曝气池中添加悬浮填料对传统活性污泥法进行改进，改造工程简单，并可使原有污水处理场的处理能力及脱氮能力大大提高；悬浮填料与活性污泥法的多种变型相结合，在市场上形成了多种新型反应器和新的商品处理工艺。反应性悬浮填料的使用也已取得一系列成功经验，但仍然要注意反应性悬浮填料本身在废水中的降解问题。     

“CHINAPLAS 2011国际橡塑展”即将开幕

"CHINAPLAS 2011国际橡塑展"将于2011年5月17—20日在广州中国进出口商品交易会琶洲展馆举行,同期举行的两个活动——"回收‘瓶’台共创纪录"和"低碳塑料论坛",将聚焦现今全球市场实践绿色制造的三大关注点——生物和降解塑料、回收减排和节能,充分体现"十二五"规划内其中以"树立绿色、低碳发展理念,以节能减排"为重点的大方向。     

回收是目前"治白"的最佳手段

深圳计划全面推广可降解塑料包装制品、拉萨全面禁用一次性发泡塑料餐盒及塑料袋、北京市场上销售的一次性可降解塑料餐盒六成不合格、学校食堂使用的降解塑料餐盒添加剂卫生指标超标、一次性发泡塑料餐具正在回潮……这是近来媒体对一次性发泡塑料餐具的一系列报道,从中不难看到政府全面禁用一次性发泡塑料餐具、推广使用可降解塑料餐具的坚定决心,而市场反应则不以人的意志为转移,面对性能和价格都缺乏竞争力的降解餐具,发泡塑料餐具一次次抬头,成了"治白"中最令人头疼的一部分.     

废催化裂化催化剂的危险性及污染特征

为考察我国废催化裂化(FCC)催化剂的危险性及污染特征,以国内典型FCC装置的废催化剂为研究对象,分析其易燃性、反应性、腐蚀性、浸出毒性、毒性物质含量及急性毒性。研究发现:废FCC催化剂无易燃性、反应性、腐蚀性、急性毒性危险;未检测出具有致癌致突变性的有机污染物;废FCC催化剂的特征污染物为Ni及其化合物,Ni的浸出浓度低于国家标准限值,Ni的存在形态为Ni Al2O4尖晶石,而非具有致癌性的Ni O形态。     

木醋调质石灰石直接硫化反应特性研究

针对O2/CO2燃烧技术适于采用炉内喷钙脱硫方式脱硫而钙利用率仍有较大提升空间的问题，采用木醋废液调质改性石灰石，并利用热分析方法对木醋调质石灰石在O2/CO2气氛下的直接硫化反应特性进行了试验研究。试验结果表明石灰石经木醋调质后直接硫化反应性能显著提高，反应温度、吸收剂粒径以及反应气氛中SO2和O2的浓度都对直接硫化反应存在影响，分析认为调质对石灰石热解固体产物微观结构的改善是脱硫性能得以显著提升的主因。     

掺氧化硅粉水泥浆、砂浆和混凝土的耐久性

加拿大安大略水电研究室(Ontario Hydro Research Division)对用氧化硅粉作水泥代用品的专门研究表明,氧化硅粉水泥制品具有较强的抗硫酸盐侵蚀性、抗骨料碱化反应性和抗冻融性。 1.只要使用20％氧化硅粉,则低水灰比(W/CM)水泥浆的孔隙率和渗透率均会降低,而且其中易浸析的氢氧化钙成份也将被全部利用。     

关于加强报废汽车拆解行业危险废弃物处理监管的提案

正案由:随着我国经济高速发展30多年,危险废弃物管理逐渐成为我国环境保护工作的重点。由于危险废弃物的环保属性比资源属性更为重要,其具有腐蚀性、毒性、易燃性、反应性及感染性等危险特性,操作、储存、运输、处理和处置不当会对人体健康或环境带来重大威胁,不仅涉及社会安全问题,更是一个影响深远的环保问题,备受公众高度关注热议。当前,危险废物管理暴露出一些新的薄弱环节,需要进一步加强,尤其     

Biodegradation and Ecotoxicity of Polyethylene Films Containing Pro-Oxidant Additive

The worldwide accumulation of non-degradable plastic materials, such as plastic bags, is one of the most important environmental concerns nowadays. The use of degradable materials is an option to mitigate the environmental impact generated by the consumption of plastics. One of the technologies used for the manufacture and use of degradable plastics is the use of pro-degradant additives that are incorporated in conventional plastics to promote their degradation under certain conditions. The aim of this study is to evaluate the process of oxidation, biodegradation and potential ecotoxicity of polyethylene films containing an oxo-degradable additive, according to the standard ASTM D-6954. This method establishes a procedure in which the samples are subjected to consecutive steps of accelerated oxidation, biodegradation by composting and ecotoxicity assessment. Furthermore, the effect of the presence of printing ink in the polyethylene samples with oxo-degradable additive was evaluated, and the results were compared with those obtained for samples of conventional polyethylene and polylactic acid. After 180 days of laboratory controlled composting, the samples reached the following percentages of biodegradation: polylactic acid, 41 %; printed oxo-degradable polyethylene, 32.24 %; oxo-degradable polyethylene, 25.84 %; printed polyethylene, 18.23 % and polyethylene, 13.48 %. The cellulose sample used as a control was mineralized in 58.45 %. Ecotoxicity assessment showed that the products of biodegradation of the samples tested, did not generate a negative effect on germination or development of the vegetal species studied. Under proper waste management conditions, these plastics can be used as an option to decrease the environmental impact of plastic films.     

Effect of Sugar Palm Fiber (SPF) to the Structural and Optical Properties of Bioplastics (SPF/Starch/Chitosan/Polypropylene) in supporting Mechanical Properties and Degradation Performance

Journal of Polymers and the Environment - Recycling plastic waste by mix with natural polymers for bio-plastic packaging produces plastics with high mechanical properties and easily degradable. In...     

Synthesis of3H- polyethylene and its use for fate studies on degradable plastics

Determining the fate of xenobiotic materials in the environment can be aided by the use of radioactive isotope technology. Previous research on the degradation of polymers such as polyethylene (PE) was aided by the utilization of radiotracers. In order to study the environmental fate of degradable (PE/starch) plastics, we synthesized³H-labeled PE. Results of soil incubation studies indicate that only minimal degradation of the PE component, as indicated by the production of water-soluble metabolites, occurred during 2 years of incubation in soil. Despite the minimal degradation, the³H label did not allow for detection of the degradation products. In addition, the³H-PE was particularly useful for tracing the fate of degradable plastics after consumption by terrestrial isopods. The detection of aqueous-soluble radioactivity in isopod frass was used to indicate degradation of the plastic film.     

Comparison of the weight-loss degradability of various biodegradable plastics under laboratory composting conditions

Eight kinds of biodegradable plastics were compared for their degradability in controlled laboratory composting conditions. A thin film of each plastic was mixed into the composting material, and weight-loss degradability was calculated from the weight changes of the film during composting. It was found that weight-loss degradability strongly depended on the specific kind of biodegradable plastic; two were very high, four moderate, and the remaining two very slight. The most easily degradable plastic degraded by as much as 81.4% over 8 days of composting. By comparing the weight-loss degradability with ultimate degradability, which is defined as a molar ratio of carbon loss as CO₂ to the carbon contained in the biodegradable plastic, the order of the ease of degradation of the biodegradable plastics differed. Received: February 7, 2000 / Accepted April 14, 2000     

Biodegradability of degradable plastic waste.

Plastic waste constitutes the third largest waste volume in Malaysian municipal solid waste (MSW), next to putrescible waste and paper. The plastic component in MSW from Kuala Lumpur averages 24% (by weight), whereas the national mean is about 15%. The 144 waste dumps in the country receive about 95% of the MSW, including plastic waste. The useful life of the landfills is fast diminishing as the plastic waste stays un-degraded for more than 50 years. In this study the compostability of polyethylene and pro-oxidant additive-based environmentally degradable plastics (EDP) was investigated. Linear low-density polyethylene (LLDPE) samples exposed hydrolytically or oxidatively at 60 degrees C showed that the abiotic degradation path was oxidative rather than hydrolytic. There was a weight loss of 8% and the plastic has been oxidized as shown by the additional carbonyl group exhibited in the Fourier transform infra red (FTIR) Spectrum. Oxidation rate seemed to be influenced by the amount of pro-oxidant additive, the chemical structure and morphology of the plastic samples, and the surface area. Composting studies during a 45-day experiment showed that the percentage elongation (reduction) was 20% for McD samples [high-density polyethylene, (HDPE) with 3% additive] and LL samples (LLDPE with 7% additive) and 18% reduction for totally degradable plastic (TDP) samples (HDPE with 3% additive). Lastly, microbial experiments using Pseudomonas aeroginosa on carbon-free media with degradable plastic samples as the sole carbon source, showed confirmatory results. A positive bacterial growth and a weight loss of 2.2% for degraded polyethylene samples were evident to show that the degradable plastic is biodegradable.     

Thermal and Rheological Properties of Commercial-Grade Poly(Lactic Acid)s

Poly(lactic acid) is the subject of considerable commercial development by a variety of organizations around the world. In this work, the thermal and rheological properties of two commercial-grade poly(lactic acid)s (PLAs) are investigated. A comparison of the commercial samples to a series of well-defined linear and star architecture PLAs provides considerable insight into their flow properties. Such insights are valuable in deciding processing strategies for these newly emerging, commercially significant, biodegradable plastics. Both a branched and linear grade of PLA are investigated. The crystallization kinetics of the branched polymer are inferred to be faster than the linear analog. Longer relaxation times in the terminal region for the branched material compared to the linear material manifests itself as a higher zero shear rate viscosity. However, the branched material shear thins more strongly, resulting in a lower value of viscosity at high shear rates. Comparison of the linear viscoelastic spectra of the branched material with the spectra for star PLAs suggests that the branched architecture is characterized by a span molecular weight of approximately 63,000 g/mol. The present study conclusively demonstrates that a wide spectrum of flow properties are available through simple architectural modification of PLA, thus allowing the utilization of this important degradable thermoplastic in a variety of processing operations.     

我国废塑料回收利用技术的发展

从我国废塑料回收利用的现状出发，分析了今后我国废塑料回收利用技术的发展趋势和应采取的措施，指出了废塑料回收利用的重要性。     

Risk assessment of an old landfill regarding the potential of gaseous emissions – A case study based on bioindication,FT-IR spectroscopy and thermal analysis

Risk assessment of two sections (I and II) of an old landfill (ALH) in Styria (Austria) in terms of reactivity of waste organic matter and the related potential of gaseous emissions was performed using conventional parameters and innovative tools to verify their effectiveness in practice. The ecological survey of the established vegetation at the landfill surface (plant sociological relevés) indicated no relevant emissions over a longer period of time. Statistical evaluation of conventional parameters reveals that dissolved organic carbon (DOC), respiration activity (RA₄), loss of ignition (LOI) and total inorganic carbon (TIC) mostly influence the variability of the gas generation sum (GS₂₁). According to Fourier Transform Infrared (FT-IR) spectral data and the results of the classification model the reactivity potential of the investigated sections is very low which is in accordance with the results of plant sociological relevés and biological tests. The interpretation of specific regions in the FT-IR spectra was changed and adapted to material characteristics. Contrary to mechanically–biologically treated (MBT) materials, where strong aliphatic methylene bands indicate reactivity, they are rather assigned to the CH vibrations of plastics in old landfill materials. This assumption was confirmed by thermal analysis and the characteristic heat flow profile of plastics containing landfill samples. Therefore organic carbon contents are relatively high compared to other stable landfills as shown by a prediction model for TOC contents based on heat flow profiles and partial least squares regression (PLS-R). The stability of the landfill samples, expressed by the relation of CO₂ release and enthalpies, was compared to unreactive landfills, archeological samples, earthlike materials and hardly degradable organic matter. Due to the material composition and the aging process the landfill samples are located between hardly degradable, but easily combustible materials and thermally resistant materials with acquired stability.     

Open windrow composting of polymers: an investigation into the operational issues of composting polyethylene (PE)

This paper investigates the operational issues surrounding the open windrow composting of degradable polyethylene sacks. Areas for consideration were the impact of degradable polyethylene sacks on the composting process, the quality of the finished compost product, and how the use of sacks influenced the on-site processing. These factors were investigated through determining the amount of polymer residue and chemical contaminants in the finished compost product and the daily monitoring of windrow temperature profiles. Site and practical handling considerations of accepting an organic waste contained within PE sacks are also discussed. Statistical analysis of the windrow temperature profiles has led to the development of a model that can help to predict the expected trends in the temperature profiles of open compost windrows where the organic waste is kerbside collected using a degradable PE sack.