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71.
综合评价值的计算已成为农业循环经济发展水平定量评价的主要方法,也是目前循环经济研究领域定量研究的热点之一。构建一套系统科学的农业循环经济发展评价指标体系,对区域农业循环经济发展水平进行综合评价,以改善农业环境,杜绝资源浪费,实现农业可持续发展具有重要的理论和现实意义。依据循环经济发展的“4R”原则和可持续发展理论,构建了甘肃省农业循环经济评价指标体系,采用因子分析法和加权函数法对甘肃省及其14个地州市的农业循环经济发展水平进行了综合评价与分析,提出了甘肃省及其各区域的农业循环经济发展建议。 相似文献
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红壤稻田系统有机物循环再利用潜力及增产作用 总被引:7,自引:0,他引:7
10年田间试验结果表明:红墩妥田系统有机养分循环再利用潜力大,水稻收获,年均从稻田系统中输出NPK的总量最大可达到224.7,53.0和271.4kg/hm^2,有机物循环再利用,年均可归N,P,K量最大分别为115.1,35.8和231.5kg/hm^2,占系统输总量的51.2%,67.5%g和85.3%,保持稻田系统内有机物循环再利用可提高系统生产力,在不施化肥的情况下,增产3056kg/hm^2,增施N肥,增产2753kg/hm^2,增施N,P肥,增产1543kg/hm^2;NPK配合,增产984kg/hm^2;有机物循环再利用还可增强稻田系统的稳产性能,降低稻谷产量的年际变异系数;有机物循环再利用对水稻的增产有着明显的残效叠加作用,在施用N,P,K化肥基础上圾机物养分循环再利用水稻增产率在试验期间的前5年为7.2%,后5年平均为9.4%。 相似文献
74.
Extended producer responsibility is advocated for its capacity to spur resource efficiency through green innovation and closing loops downstream of consumption. Its rationale is the extension of the polluter-pays principle to the post-consumption phase. This paper analyze the underlying mechanisms that are supposed to work under the EPR approach, and proposes an alternative view. The main purpose of EPR is seen as the creation of the bases for legitimizing the involvement if industry taking over the task of diverting waste from landfill. Its success rests on the superior managerial capacity of industry and the need to organize post-consumption markets that transcend the local scale and have access to the economies of scale and scope. The emphasis on producers does not add anything special, but may reinforce the bases for legitimizing the implicit delegation of power to industry. Primary and above all, we have witnessed in the last 20 years a gigantic effort of market design, and this is the main demonstration of EPR's success. 相似文献
75.
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. 相似文献
76.
Recycling End of Life (EOL) concrete into high-grade aggregate for new concrete is a challenging prospect for the building sector because of the competing constraints of low recycling process cost and high aggregate product quality. A further complicating factor is that, from the perspective of the environment, there is a strong societal drive to reduce bulk transport of building materials in urban environments, and to apply more in situ recycling technologies for Construction & Demolition Waste. The European C2CA project investigates a combination of smart demolition, grinding of the crushed concrete in an autogenous mill to increase the liberation of cement mortar from the surface of aggregates and a novel dry classification technology called ADR to remove the fines. The feasibility of this recycling process was examined in a demonstration project involving 20,000 tons of EOL concrete from two office towers in Groningen, the Netherlands. Results show that the +4 mm recycled aggregate compares favorably with natural aggregate in terms of workability and the compressive strength of the new concrete, showing 30% higher strength after 7 days. 相似文献
77.
A holistic evaluation of the feasibility of producing 100% recycled mixtures is presented. Eleven technologies readily available for producing 100% Reclaimed Asphalt Pavement (RAP) hot asphalt mixtures are described in the article and the complementary video (http://youtu.be/coj-e5mhHEQ). The recorded performance of 100% RAP mixtures is analyzed along with identification of typical high RAP distresses. Recommended mix design procedures and the best RAP management strategies are described. A cradle-to-gate analysis of environmental effects indicated 18 kg or 35% CO2eq savings per t of produced 100% RAP asphalt mixture compared to virgin mix, while cost analysis showed at least 50% savings in material related expenses. 相似文献
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