日本废弃小型电子产品循环要利用状况

日本政府自2013年4月1日开始实施《废弃小型电子产品循环再利用促进法》.基于此法的第三条第一款,日本环境省和经济产业省于2013年3月6日正式出台了基本方针,制定了再资源化目标,即至2015年止,每年回收14万t(相当于每人1 kg)废旧手机等小型电子产品,回收率达到20％左右,并介绍了其主要内容及目前的实施状况.     

资源循环是再利用的灵魂——“3R”学习与探讨之二

再利用强调了物质层面的资源再生和循环利用,是解决原生资源匮乏和开辟新型工业道路有效的手段。不仅对于我国经济和社会可持续发展具有强大的推动作用,也对于资源国际大循环起到促进作用。再利用过程中需要在提高利用率和有效防治二次污染两方面下功夫,以实现变废为宝,降低乃至消除无价值废物的协同目标。     

金属镁渣的回收利用现状

近年来,我国镁冶炼行业快速发展,随着原镁和镁合金年产量的逐年增高,排放出来的镁渣也越来越多,如何有效合理地处理、开发利用镁渣,达到节约能源、节约资源、变废为宝和变害为利的目的,是当前迫切需要解决的问题。对近年来我国有关镁渣的研究应用情况进行全面的总结。     

废旧塑料分选及其化学回收循环再利用技术研究进展

塑料污染已是全球防治环境污染的重大问题,我国每年有大量的废旧塑料产生,仅废旧塑料的分选这一工艺就要耗费大量的人力物力财力,回收后的循环再利用,又要增加昂贵的处理成本。综述了废旧塑料几种主要的分选技术,包括色彩分选技术、光谱分选技术、密度分选技术、风力分选技术、静电分选技术、溶剂萃取分选技术。对废旧塑料化学回收循环利用相关技术进行介绍,包括热裂解法、催化裂解法、氢化裂解法、光催化裂解法等。总结了对废旧塑料分选及化学回收循环再利用的重要性,并对此提出了规模化、产业化的发展愿景。     

建筑垃圾循环利用实践

建筑垃圾的循环利用是今后建筑垃圾处理的必经之路。在对国内外建筑垃圾循环利用的相关政策、法律法规及回收现状进行比较分析的基础上,对目前建筑垃圾循环利用的案例进行调查整理,总结出建筑垃圾循环利用的一般过程;并在对目前建筑垃圾循环利用的方法进行研究后,介绍了一种先进实用的建筑垃圾循环利用方法;最后对我国建筑垃圾循环利用存在的问题进行剖析并提出解决问题的建议,以期对我国建筑垃圾循环利用的发展有所裨益。     

日本废物循环利用技术简介

在一系列法律法规政策的支持下,日本废物循环技术处于世界领先水平。介绍了几种日本废物利用的技术研究,为促进我国废物循环利用技术水平的提高提供参考。     

磷化渣的再生利用

磷化渣的再生利用在钢铁、机械等行业，为使加工的金属（主要是钢铁）表面形成一层致密的磷化膜，目前仍普遍沿袭简单而有效的磷化处理工艺。经磷化处理形成的磷化膜，可将金属基体与外界隔开，使其具有良好的防锈能力，并提高其对涂料的附着力，同时在金属的冷加工中起到...     

利用膜技术实现烟气脱硫吸收剂循环的研究

利用膜技术实现钠碱法脱硫吸收液的再生循环,流程简单,操作方便。通过介绍钠碱法脱硫吸收液再生原理,探讨了NaHSO3-Na2SO3溶液吸收与再生循环操作流程,分析了膜技术推广应用中存在的主要问题。     

高校大学生教材循环利用态度的调查分析

高校教材数量多,使用寿命短,每年毕业季大量教材被废弃或当做废纸卖掉,缺乏良好的处理途径,造成严重的资源浪费.在提倡节约型社会和可持续发展的大背景下,以网络问卷的方式调查了在校大学生目前的教材利用情况以及对教材循环利用的态度,并查阅相关文献资料,综合分析实施教材循环的基础和现状,并提出相应的可行性措施和建议.调查结果表明...     

Recycling and reuse of industrial wastes in Taiwan

Eighteen million metric tons of industrial wastes are produced every year in Taiwan. In order to properly handle the industrial wastes, the Taiwan Environmental Protection Administration (Taiwan EPA) has set up strategic programs that include establishment of storage, treatment, and final disposal systems, establishment of a management center for industrial wastes, and promotion of recycling and reuse of industrial wastes. The Taiwan EPA has been actively promoting the recycling and reuse of industrial wastes over the years. In July 1995 the Taiwan EPA amended and promulgated the Criteria for the Industrial Waste Storage, Collection and Processing Facility, July, 1995 that added articles related to general industrial waste recycling and reuse. In June 1996 the Taiwan EPA promulgated the Non-listed General Industrial Waste Reuse Application Procedures, June, 1996, followed by the Regulations Governing the Permitting of Hazardous Industrial Waste Reuse, June 1996, setting up a full regulatory framework for governing industrial waste reuse. To broaden the recycling and reuse of general industrial wastes, the Taiwan EPA has listed 14 industrial waste items for recycling and reuse, including waste paper, waste iron, coal ash, tempered high furnace bricks (cinder), high furnace bricks (cinder), furnace transfer bricks (cinder), sweetening dregs, wood (whole/part), glass (whole/part), bleaching earth, ceramics (pottery, brick, tile and cast sand), individual metal scraps (copper, zinc, aluminum and tin), distillery grain (dregs) and plastics. As of June 1999, 99 applications for reuse of industrial wastes had been approved with 1.97 million metric tons of industrial wastes being reused.     

固体废弃物在家具产品中的再生利用探析

从家具行业可持续发展角度出发,结合国内外经典案例,阐述了国内家具设计中对固体废弃物利用不足的现状,并从政策、企业、设计者和消费者4个角度,对固体废弃物在家具产品中的再生利用提出建议。     

Fenton试剂处理汽车油漆废渣

采用Fenton试剂处理汽车油漆废渣。考察了FeSO_4用量、H_2O_2用量、反应温度、反应时间对处理效果的影响。实验结果表明,在FeSO_4用量为20.5 mg/g、H_2O_2用量为0.6 g/g、反应温度为80 ℃、反应时间为3 h的最优条件下,清漆渣、色漆渣、底漆渣3种漆渣的干基减量率均为20%左右,湿基减量率分别为67.9%、48.2%和64.2%,3种产物的脱水性能均有不同程度的提高,处理后废液的COD均为2 000 mg/L左右。采用Fenton试剂处理后的清漆渣产物粒径与原料相似,产物颗粒球形度高,表面粗糙,内部为多孔结构,产物作为固体燃料时燃烧更充分。Fenton试剂处理未对漆渣中的树脂主体产生较大的破坏。     

Innovative reuse of drinking water sludge in geo-environmental applications

In recent years, the replacement of natural raw materials with new alternative materials, which acquire an economic, energetic and environmental value, has gained increasing importance. The considerable consumption of water has favoured the increase in the number of drinking water treatment plants and, consequently, the production of drinking water sludge. This paper proposes a protocol of analyses capable of evaluating chemical characteristics of drinking water sludge from surface water treatment plants. Thereby we are able to assess their possible beneficial use for geo-environmental applications, such as the construction of barrier layers for landfill and for the formation of “bio-soils”, when mixed with the stabilized organic fraction of municipal solid waste. This paper reports the results of a study aimed at evaluating the quality and environmental aspects of reconstructed soils (“bio-soil”), which are used in much greater quantities than the usual standard, for “massive” applications in environmental actions such as the final cover of landfills. The granulometric, chemical and physical analyses of the sludge and the leaching test on the stabilized organic fraction showed the suitability of the proposed materials for reuse.The study proved that the reuse of drinking water sludge for the construction of barrier layers and the formation of “bio-soils” reduces the consumption of natural materials, the demand for landfill volumes, and offers numerous technological advantages.     

Bioconversion of industrial wastes: paint sludge from automotive manufacturing

The compostability of water-based paint sludge originating from the automotive industry was investigated. Six reactors were operated. Wastewater treatment sludge from the same industry was used as additional substrate, and corncob was used as a bulking agent. The level of paint sludge within the compost mixtures varied between 55 and 85%. All reactors yielded a temperature increase up to thermophilic phase levels (>?40 °C) for a minimum of 5 days, and organic matter and C/N losses were observed. BTEX concentrations decreased during composting. Nickel and tin levels in the final product exceeded the legal compost limits. The calorific value of the compost mixtures increased from 9532 to 18774 kJ/kg at the end of the composting process. It was seen that the process applied in this study can be utilized as a biodrying step before the usage of paint sludge at cement kilns as additional fuel.     

Recycling glass-polishing sludge and aluminum anodising sludge in polyurethane and cement composites: fire performance and mechanical properties

Journal of Material Cycles and Waste Management - This article aims to study the mechanical strength and fire resistance of polyurethane/cement (PuCem) composites containing glass sludge and sludge...     

Recycling and reuse of waste from electricity distribution networks as reinforcement agents in polymeric composites

Of the waste generated from electricity distribution networks, wooden posts treated with chromated copper arsenate (CCA) and ceramic insulators make up the majority of the materials for which no effective recycling scheme has been developed. This study aims to recycle and reuse this waste as reinforcement elements in polymer composites and hybrid composites, promoting an ecologically and economically viable alternative for the disposal of this waste. The CCA wooden posts were cut, crushed and recycled via acid leaching using 0.2 and 0.4 N H₂SO₄ in triplicate at 70 °C and then washed and dried. The ceramic insulators were fragmented in a hydraulic press and separated by particle size using a vibrating sieve. The composites were mixed in a twin-screw extruder and injected into the test specimens, which were subjected to physical, mechanical, thermal and morphological characterization. The results indicate that the acid treatment most effective for removing heavy metals in the wood utilizes 0.4 N H₂SO₄. However, the composites made from wood treated with 0.2 N H₂SO₄ exhibited the highest mechanical properties of the composites, whereas the use of a ceramic insulator produces composites with better thermal stability and impact strength. This study is part of the research and development project of ANEEL (Agência Nacional de Energia Elétrica) and funded by CPFL (Companhia Paulista de Força e Luz).     

酸浸出法回收冶金污泥中的有价金属

采用二次酸浸出的方法回收镍钴湿法冶金工业污泥中的有价金属。先采用水和硫酸作为浸出剂浸出Mg和Na,最佳工艺条件为浸出液的pH 7.5、浸出时间5 min、浸出剂体积与干污泥质量的比(ω)为10 mL/g。再采用硫酸作为浸出剂、焦亚硫酸钠作为还原剂进行二次酸浸,在硫酸与污泥质量比为1.3、焦亚硫酸钠与污泥质量比为0.3、ω为5 mL/g、浸出温度85℃、浸出时间20 min的最佳工艺条件下,Co、Ni、Cu、Mn和Zn的浸出率分别达92.45%、93.48%、89.52%、97.78%和94.79%。经XRD表征,浸出后污泥中未见原污泥中的矿物相,说明原污泥中的矿物几乎全部被溶解。     

Rapid-extraction oxidation process to recover and reuse copper chromium and arsenic from industrial wood preservative sludge

Chromated copper arsenate (CCA) wood preservative can form insoluble sludges when the hexavalent chromium component is reduced by wood extractives, wood particles and preservative additives in the solution. This sludge accumulates in treating solution work tanks, sumps and in-line filters and must be disposed of as hazardous wastes by waste disposal companies at high costs. A number of commercial sludges were investigated and found to contain 18-94% copper, chromium and arsenic as oxides combined with sand, oil, wood particles, additives and wood extractives. We have developed a multi-stage recycling process whereby approximately 97% of the CCA components are recovered from the sludge. It involves extraction with sodium hypochlorite to remove and oxidize chromium (more than 90%) and extract most of the arsenic (approx. 80%) followed by extraction of the copper and remaining arsenic and chromium with phosphoric acid. The phosphoric acid extract contains some trivalent chromium, which is subsequently oxidized by sodium hypochlorite. The combined oxidized extract containing CrVI, CuII and AsV was compatible with CCA treating solutions and could be re-used commercially for treating wood without having a significant effect on the preservative fixation rate or the leach resistance of the treated wood. A cost analysis showed that the economic savings from recovery of CCA chemicals and reduced landfill costs exceeded the variable costs for materials and energy for the process by as much as Can $966 per tonne of sludge if sodium sulfite can be acquired in bulk quantities for the process.     

Recycling of calcium fluoride sludge as ceramic material using low temperature sintering technology

The Chinese integrated circuit industry has been transformed from a small state-owned sector into a global competitor, but chip manufacturing produces large amounts of calcium fluoride sludge (CFS). The current treating method is landfill in China. In order to solve the problem of unavailable landfill sites and the dissolved CFS polluting water sources, CFS was tested as a component for a ceramic product made with sodium borate, sodium phosphate, and waste alumina using a low temperature sintering technology. The ceramic was characterized by X-ray diffraction (XRD), microstructure, compressive strength. XRD and microstructure analyses verified that CFS was transformed into Na₂Ca(PO₄)F as an inert crystalline phase in ceramic, which is enclosed by the borophosphate glass liquid phase. Toxicity characteristic leaching procedure and corrosion resistance tests verified that fluorine from CFS was solidified in the inert crystalline phase, which did not release to cause secondary pollution. This novel technology produces high-performance ceramic as a construction material, in accordance with the concept of sustainable development.