中国湿巾代谢分析及环境影响评估

为评估湿巾塑料消耗及污染现状,比较不同材质湿巾环境影响表现,开展了中国湿巾"生产-使用-废弃处置"全过程物质流分析,通过市场调研获知湿巾材质分布,开展全国消费者问卷调查获知废弃湿巾流向.对不同材质湿巾开展全生命周期环境影响评价,系统比较评估其环境影响.结果表明,"70%聚酯纤维+30%粘胶纤维"混合材质湿巾是中国最为常见的湿巾类型,2019年中国湿巾用塑量达41万t,经消费者使用丢弃后约有18.9%直接泄露进入自然环境.在焚烧、填埋处置方式中,全粘胶纤维湿巾全生命周期综合环境影响比全聚酯纤维湿巾低38%,前者水污染突出但资源消耗、毒性风险优势明显;在直接泄露方式中,全粘胶纤维湿巾可避免聚酯纤维泄露后崩解为微塑料纤维的环境风险.     

长征国家文化公园红色旅游资源网络关注度及其旅游流网络结构分析

长征国家文化公园建设面临着的现实需求和复杂问题,迫切要求开展相应的系统性研究工作。以长征国家文化公园内154处重点红色旅游资源为研究对象,基于“虚拟”与“现实”相结合的视角,使用GIS、Gephi等研究方法,对其网络关注度和旅游流网络结构进行分析。研究表明：（1）红色旅游资源网络关注度普遍偏低、差异明显,5A级景区和重要人物是最受网络用户关注的资源类型;（2）旅游流网络结构松散、小世界效应显著,在湖南、贵州、陕西省内分别形成了“△”“网状”“双核”结构模式;（3）网络关注度与旅游流网络具有关联性和差异性,据此识别了湘中、黔川、陕北等重点红色旅游区,以及川陕、闽赣等红色旅游发展潜力区。基于以上分析,长征国家文化公园建设应以重点红色旅游资源为基础,实施分类施策、分段开发、扬长补短的发展策略。围绕高高、高低、低高、低低四种不同类型资源制定相应的发展策略,并结合不同区域的发展情况分别采取“节点”“斑块”“廊道”相结合的发展模式。     

针对工作流量为2 L·min-1的切割器的捕集效率评价研究

为了评价市面上不同工作流量的切割器,本研究搭建了一套基于静态箱法的切割器捕集效率评价系统,可调节切割器的采样流量,结合空气动力学粒径谱仪对不同工作流量的切割器进行捕集效率测量.通过使用8种粒径的单分散聚苯乙烯微球,对多个品牌的工作流量为2、3及16.67 L·min^-1的PM₁、PM_2.5及PM₁₀切割器进行了评价,得到其捕集效率为50%时的空气动力学粒径分别为1.12、2.52和10.39 μm（品牌一）;2.69和10.41 μm（品牌二）;2.56、10.43 μm（型号Dust trak）;1.04、2.51 μm（型号VSCC）.本研究对于评价不同流量、不同原理的切割器的性能、提高颗粒物监测结果的准确性具有一定的科学意义.     

基于要素流动的城镇建设用地配置方法框架探讨

现有城镇建设用地配置主要遵循空间开发导向,利用静态数据和用地分配标准、评估及预测模型开展,存在一定的“区域偏好”和“规模求大”现象。在强调生态文明建设和高质量发展的新时期,国土空间规划战略实施要求城镇建设用地配置方法需要及时革新。关注到信息或智能技术深度影响下未来城镇场所空间将转变为流动空间这一必然趋势,不同尺度生产、生活及生态要素时空流动与分配将是城镇建设用地科学配置的关键。因此,利用多源要素流大数据和多学科分析方法,试图从城镇空间发展水平评价、城镇要素流动网络时空模拟与用地分配、城镇要素功能区识别与开发边界划定、城镇建设用地配置效果动态评估4个方面,建立基于要素流动的城镇建设用地配置方法框架。结果表明：（1）城镇空间发展水平评价需要综合考虑城镇对区域现状要素控制、吸引及溢出的能力,并从空间发展规模、活力及品质三个层面构建评价指标体系;（2）在城镇建设用地指标区域分配过程中注重利用网络优化模型和社会网络分析方法刻画区域要素流动规律,并通过时空耦合模型找出不同等级和类型“空间发展水平—要素控制力”组合的城镇;（3）城镇未来扩展方向和边界形态是由内部各类要素流动变化与功能空间布局的供需时空匹配情况决定的,需要利用时空耦合、引力、CA及多智能体等模型识别要素功能影响区和流动偏好;（4）城镇建设用地配置效果评估指标需要体现生态文明、高质量、智慧治理及一体化等未来城镇发展要求和趋势。这些研究结果可以为国土空间规划城镇开发边界划定和实施提供参考。     

中国玻璃物质流分析和未来需求预测研究

使用物质流分析方法和情景分析法探讨了1949~2050年玻璃的物质流动和初级资源可持续性.结果表明,废日用玻璃和废玻璃纤维是资源损失的关键节点;在不同需求增长率下,初级资源需求会在2030~2050年某个时期超过当前资源储量.2045年前,期望将废平板玻璃回收利用率提高到70%、废日用玻璃回收利用率提高到60%,使玻璃硅质资源可以满足低增长需求.为了达到循环目标,政府应持续推进垃圾分类,鼓励企业从设计端延长玻璃产品寿命,提高回收利用技术,建立完善的回收再利用体系.     

水下枪炮发射问题研究综述

首先介绍了水下枪炮类武器发射问题的研究意义,并对其军事需求进行了分析。之后对常见的水下枪炮发射方式进行了介绍,并简述了各自的发展历程。总结了目前对水下发射问题内弹道的研究进展,结合水下枪炮发射问题自身特点,阐述了燃气射流的形成机理以及相关研究的发展过程,比较性地总结了空气中枪炮发射膛口流场与水下枪炮发射膛口流场的研究进展及对应典型波系结构。最后,对水下枪炮发射领域仍存在的科学问题以及未来发展趋势作出了展望。     

A waste management planning based on substance flow analysis

The paper describes the results of a municipal solid waste management planning based on an extensive utilization of material and substance flow analysis, combined with the results of specific life cycle assessment studies. The mass flow rates of wastes and their main chemical elements were quantified with a view to providing scientific support to the decision-making process and to ensure that the technical inputs to this process are transparent and rigorous. The role of each waste management option (recycling chains, biological and thermal treatments), as well as that of different levels of household source separation and collection (SSC), was quantitatively determined. The plant requirements were consequently evaluated, by assessing the benefits afforded by the application of high quality SSC, biological treatment of the wet organic fraction, and thermal treatment of unsorted residual waste. Landfill volumes and greenhouse gas emissions are minimized, toxic organic materials are mineralized, heavy metals are concentrated in a small fraction of the total former solid waste volume, and the accumulation of atmophilic metals in the air pollution control residues allows new recycling schemes to be designed for metals. The results also highlight that the sustainability of very high levels of SSC is reduced by the large quantities of sorting and recycling residues, amounts of toxic substances in the recycled products, as well as logistic and economic difficulties of obtaining very high interception levels. The combination of material and substance flow analysis with an environmental assessment method such as life cycle assessment appears an attractive tool-box for comparing alternative waste management technologies and scenarios, and then to support waste management decisions on both strategic and operating levels.     

A future perspective on lithium-ion battery waste flows from electric vehicles

As a proactive step towards understanding future waste management challenges, this paper presents a future oriented material flow analysis (MFA) used to estimate the volume of lithium-ion battery (LIB) wastes to be potentially generated in the United States due to electric vehicle (EV) deployment in the near and long term future. Because future adoption of LIB and EV technology is uncertain, a set of scenarios was developed to bound the parameters most influential to the MFA model and to forecast “low,” “baseline,” and “high” projections of future end-of-life battery outflows from years 2015 to 2040. These models were implemented using technology forecasts, technical literature, and bench-scale data characterizing battery material composition. Considering the range from the most conservative to most extreme estimates, a cumulative outflow between 0.33 million metric tons and 4 million metric tons of lithium-ion cells could be generated between 2015 and 2040. Of this waste stream, only 42% of the expected materials (by weight) is currently recycled in the U.S., including metals such as aluminum, cobalt, copper, nickel, and steel. Another 10% of the projected EV battery waste stream (by weight) includes two high value materials that are currently not recycled at a significant rate: lithium and manganese. The remaining fraction of this waste stream will include materials with low recycling potential, for which safe disposal routes must be identified. Results also indicate that because of the potential “lifespan mismatch” between battery packs and the vehicles in which they are used, batteries with high reuse potential may also be entering the waste stream. As such, a robust end-of-life battery management system must include an increase in reuse avenues, expanded recycling capacity, and ultimate disposal routes that minimize risk to human and environmental health.     

The Austrian P budget as a basis for resource optimization

Phosphorus (P) is a finite and non-substitutable resource that is essential to sustaining high levels of agricultural productivity but is also responsible for environmental problems, e.g., eutrophication. Based on the methodology of Material Flow Analysis, this study attempts to quantify all relevant flows and stocks of phosphorus (P) in Austria, with a special focus on waste and wastewater management. The system is modeled with the software STAN, which considers data uncertainty and applies data reconciliation and error propagation. The main novelty of this work lies in the high level of detail at which flows and stocks have been quantified to achieve a deeper understanding of the system and to provide a sound basis for the evaluation of various management options. The budget confirms on the one hand the dependence of mineral P fertilizer application (2 kg cap⁻¹ yr⁻¹), but it highlights on the other hand considerable unexploited potential for improvement. For example, municipal sewage sludge (0.75 kg cap⁻¹ yr⁻¹) and meat and bone meal (0.65 kg cap⁻¹ yr⁻¹) could potentially substitute 70% of the total applied mineral P fertilizers. However, recycling rates are low for several P flows (e.g., 27% of municipal sewage sludge; 3% of meat and bone meal). Therefore, Austria is building up a remarkable P stock (2.1 kg P cap⁻¹ yr⁻¹), mainly due to accumulation in landfills (1.1 kg P cap⁻¹ yr⁻¹) and agricultural soils (0.48 kg P cap⁻¹ yr⁻¹).     

Multi-objective optimization of waste and resource management in industrial networks – Part II: Model application to the treatment of sewage sludge

In the present article, the thermal treatment of digested sewage sludge generated in the Swiss region of Zürich is modeled and optimized from an environmental perspective. The optimization problem is solved using a multi-objective mixed-integer linear program that combines material flow analysis, process models, life cycle assessment (LCA), and mathematical optimization techniques. The treatment options include co-incineration in municipal solid waste incineration, co-processing in cement production, and mono-incineration with the prospect of phosphorus recovery. The model is optimized according to six environmental objectives. Five of the six single-objective optimal solutions involve splits over the treatment options. The results reflect the available treatment capacities and other constraints, aspects rarely considered in conventional LCA studies. Co-processing in cement production is used to the maximum extent possible when minimizing impacts on climate change, human toxicity, fossil resource depletion, and fully aggregated impacts (ReCiPe H/A), whereas mono-incineration with phosphorus recovery receives the bulk of the sludge when optimizing for ecotoxicity and mineral resource depletion. Four of the single-objective optimal solutions (minimization of fossil energy resource depletion and contribution to climate change, human toxicity, and fully aggregated impacts) outperform the reference case over the six impact categories considered, showing that the current situation can be improved in some environmental categories without compromising others. The results of the sensitivity analysis indicate that assumptions regarding the product systems displaced by recovered by-products are critical for the outcome of the optimization. Our approach identifies in all of the cases solutions in which significant environmental improvements can be attained.