The environmental impact of distribution to retail channels: A case study on packaged beverages

This study aims to quantify the environmental impact of two retail distribution networks and offer consumers a channel that is more beneficial to the environment. The environmental impact of replenishing the packaged beverages sold in convenience stores (CVSs) and hypermarkets is assessed using the streamlined life-cycle assessment (LCA) approach. In this study, the life-cycle impact assessment (LCIA) for packaged beverages up to the point of sale illustrates the distribution-level environmental impacts of truck transportation. The matched-pair t-test shows that the environmental impacts of transporting 1800 cartons of 24-pack/10 oz. beverages to be sold in Carrefour and 7-11 stores is different at a significance level of 0.1. The transport-focused LCA is used to improve the understanding and compare the environmental characteristics of the two distribution and retail systems. This study constitutes a vehicle for communicating to both internal and external stakeholders the environmental profiles of distributing the same product sold through two retail channels.     

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车用能源的生命周期评价（Life Cycle Assessment，LCA）较一般仅对能源使用阶段的环境影响评价方法更为系统和全面，但是在进行车用替代燃料比较研究中，由于机动车使用环境的特殊性，造成等量污染物排放在不同阶段所造成的环境损害差异悬殊，传统的LCA 方法无法准确评价不同车用替代能源的环境效应. 为此，论文在总结车用燃料生命周期评价的基础上，提出基于边际环境损害成本计算分阶段权重系数，进而对车用燃料LCA 评价做出改进，使其适用于不同车用替代燃料之间环境影响的对比分析，并选择燃料电池车与汽油车进行了实证分析.     

基于生长曲线的中国铁路网生命周期判定

运用生长曲线理论对中国铁路网演化（1949–2020 年）的生命周期进行判定,旨在得到铁路网在时空演化中的周期性变化和生长规律.根据调整拟合优度最大隶属原则,将中国铁路网演化曲线逐步融合划分成为4 个生命周期.选择四个典型的生长曲线模型,对每一个生命周期的曲线进行拟合识别,得到中国铁路网演化生命周期遵循Logistic 模型的生长规律和每个生命周期的生长曲线公式及参数.研究表明,中国铁路网演变遵循连续形生长曲线特征,分别为萌芽期（1949–1969 年）,发展期（1970–1988 年）,调整期（1989–1998 年）和繁荣期（1999–2020 年后）,每一个生命周期都遵循着发生、成长到成熟的生长特征.目前中国铁路网处于第四生命周期中的成长期,周期结束时间约为2023 年,里程将达到12.537 万km.相关部门应当根据铁路网演化生命周期的生长规律,在不同生长阶段采取相应的发展策略,指导和促进中国铁路网顺利过渡到下一生命周期.     

纯电动汽车生命周期3E评价及微型化发展

通过能耗、排放、经济等角度的分析,对燃煤发电和电动汽车为基础的电动汽车与传统汽油汽车相比较,普通电动汽车和超微电动车比常规汽油汽车和微型汽车的能效、排放、经济性都具有相对优势。以超微电动汽车为产业化突破口的市场发展策略,将促进我国从微型到常规的电气化交通能源发展。     

道路水泥混凝土的环境影响评价

简要介绍生命周期评价的概念和方法,应用生命周期评价方法评价道路水泥混凝土的环境性能。再生混凝土的环境综合指标为8 18×10-12年,普通混凝土的环境综合指标为11 57×10-12年,由此表明前者具有更好的环境协调性。再生混凝土是道路水泥混凝土可持续发展的方向之一,可以通过降低水泥的环境负荷继续提高其环境性能。     

生命周期评价在铁路节能评估中的应用研究

生命周期评价方法贯穿了评价对象的整个生命周期,是一个从"摇篮到坟墓"的全过程评价。该方法在工业、农业、建筑业和环境保护等方面均得到有效利用。本文从节能评估发展要求和趋势出发,将生命周期评价引入铁路节能评估领域,并结合国内外生命周期评价方法的研究和应用现状,尝试建立基于生命周期成本的铁路节能技术生命周期评价技术框架,旨在为铁路节能评估和管理提供理论和方法依据。     

Comparative life-cycle assessment of conventional (double lane) and non-conventional (turbo and flower) roundabout intersections

This research studied and compared different construction techniques for the road subgrade, embankment and pavement of different types of roundabout intersections in order to assess their environmental sustainability. A Life Cycle Assessment (LCA) was carried out on double lane, turbo- and flower roundabouts.We considered virgin materials and reclaimed asphalt pavement (RAP) for the pavement construction. Also the environmental effects due to in situ lime stabilization of fine-grained soils were assessed in order to reduce the use of virgin material in road subgrades.The use of reclaimed asphalt pavement (RAP) can lead to a significant reduction in pollutant emissions and energy consumption (especially due to the lesser material transport) – though with a slightly different impact according to the different percentages employed – compared to the pavements constructed with virgin materials. The same consideration can be made for fine soils with in situ lime stabilization: on the one hand, the technique allows to improve significantly the mechanical properties of soils which would be otherwise dumped and, on the other, to provide considerable environmental benefits. The life cycle assessment of the pavement was carried out with the help of the PaLATE software (by comparing different maintenance scenarios) while emissions and energy consumption in the use phase at intersections were evaluated by means of closed-form models (to estimate vehicle delays and speeds of vehicles) and the COPERT software.Finally, the generalized costs covered in the whole life cycle of roundabouts (i.e. sum of construction, maintenance and environmental costs) were assessed and associated to the different construction options.     

The importance of the use phase on the LCA of environmentally friendly solutions for asphalt road pavements

In order to assess sustainability of products and processes, different methodologies have been developed and used in the last years. In the road pavement construction area, most methodologies used for Life Cycle Assessment (LCA) are essentially focused in the construction phase. The present paper analyses the importance of the use phase of a road in the LCA of different paving alternatives, namely by evaluating energy consumption and gaseous emissions throughout the road pavement’s life. Therefore, a new LCA methodology for road pavements was developed, and the results of its application to a case study involving the construction of alternative pavement structures are discussed. The study intends to assess the influence of using more sustainable paving construction alternatives (asphalt recycling vs. conventional asphalt mixtures), and/or different surface course materials (which have a higher influence on the rolling resistance and, therefore, affect the performance during the use phase). The LCA results obtained for this case study showed that the reductions in energy consumption and gaseous emissions obtained during the use phase, for pavement alternatives with a lower rolling resistance surface course, are higher than the total amount of energy consumption and gas emissions produced during construction. It is therefore clear that some improvements in the characteristics of the surface course may have an effect over the road use phase that will rapidly balance the initial costs and gas emissions of those interventions. The LCA results obtained also showed that the sustainability of pavement construction may also be improved using recycled asphalt mixtures.     

Analyzing the effects of Gas-to-Liquid (GTL) diesel blending on the efficiency and emissions of petroleum refineries and transport fuels in the U.S. and Europe

The transport sector is fast changing with demand for distillates increasing amidst declining gasoline consumption in many markets especially in the developed world. Increasingly refineries are stretched to operate less efficiently and this is manifested through a drop in efficiency as a consequence of increasing diesel production via less efficient routes, particularly on the marginal barrel of diesel. It has been suggested that this decline in diesel production efficiency, as the ratio of gasoline to diesel (G/D) production drops, can partly be mitigated through the use of Gas-to-Liquid (GTL) diesel. In this paper we adopted refinery Linear-Programming models to represent the refining system in Europe as well as a district in the U.S. to investigate the effects of increased availability of GTL diesel to a refiner on the energy efficiency and GHG emissions of refineries. Here we showed that indeed there is an improvement in diesel production efficiency with increasing GTL concentrations, but this efficiency gain (<0.5%) is insufficient to counteract the higher energy consumption and emissions associated with the production of GTL, thus leading to an overall decline in life cycle efficiency (up to 5%), and an increase in life cycle GHG emissions (up to 2%).     

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运用生长曲线理论对中国铁路网演化（1949–2020年）的生命周期进行判定,旨在得到铁路网在时空演化中的周期性变化和生长规律.根据调整拟合优度最大隶属原则,将中国铁路网演化曲线逐步融合划分成为4个生命周期.选择四个典型的生长曲线模型,对每一个生命周期的曲线进行拟合识别,得到中国铁路网演化生命周期遵循Logistic模型的生长规律和每个生命周期的生长曲线公式及参数.研究表明,中国铁路网演变遵循连续形生长曲线特征,分别为萌芽期（1949–1969年）,发展期（1970–1988年）,调整期（1989–1998年）和繁荣期（1999–2020年后）,每一个生命周期都遵循着发生、成长到成熟的生长特征.目前中国铁路网处于第四生命周期中的成长期,周期结束时间约为2023年,里程将达到12.537万km.相关部门应当根据铁路网演化生命周期的生长规律,在不同生长阶段采取相应的发展策略,指导和促进中国铁路网顺利过渡到下一生命周期.