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391.
Tang Jiehong Tang Yuting Liu Yupeng Su Hanchen Zhang Yuxuan Sun Ziwei Ma Xiaoqian 《Journal of Material Cycles and Waste Management》2023,25(4):2442-2456
Journal of Material Cycles and Waste Management - Waste classification is comprehensively carried out in China as an important national-level policy, and the large amount and the wide range of food... 相似文献
392.
硫酸锰渣污染土壤中重金属的形态分布及生物活性 总被引:1,自引:0,他引:1
测定了硫酸锰渣污染土壤中Cu,Zn,Cd,Pb,Mn的总量和各形态含量.结果表明重金属总量远超过环境背景值和土壤环境二级标准.重金属各形态分布特征:Cu,有机态>残渣态>铁锰氧化态>碳酸盐态>可交换态;Zn,残渣态>铁锰氧化态>有机态>碳酸盐态>可交换态;Cd,铁锰氧化态>可交换态>碳酸盐态>残渣态>有机态;Pb,铁锰氧化态>残渣态>有机态>碳酸盐态>可交换态;Mn,铁锰氧化态>残渣态>可交换态>有机态>碳酸盐态.重金属的生物可利用性系数和迁移系数均为Cd>Mn>Pb>Cu>Zn. 相似文献
393.
采用延长边沟闷曝时间的方法对BOD降解模式T型氧化沟进行提高脱氮效率的改造。结果表明,边沟闷曝时间由0.5 h增至1 h,系统反硝化和硝化运行时间比tDN/tN由0.56调整至0.50时,提高了系统的NH3-N的硝化效率,强化了脱氮能力。工艺改造后出水NH3-N浓度由改造前15.5 mg/L显著降低至10.4 mg/L,达到了广东省地方标准(DB 44/26-2001)第一时段的二级排放要求;系统脱氮效率由改造前52.1%显著提高到68.3%,有效地解决了污水厂出水NH3-N浓度过高的问题;具有投资少、效果明显的特点,有一定的推广价值。 相似文献
394.
2009年7月22日上午8时左右,在我国长江中下游地区就将迎来近2000年来持续时间最长的一次日全食奇观。随着这一“美妙而壮丽”时刻的临近,长江流域30多个中城市掀起了有史以来最大的“观天”风暴,由此也带动了与日全食有关的旅游、食饮、住宿、交通、数码产品等行业和消费经济的快速升温。中国是最佳观测地也引起了世界关注。 相似文献
395.
Ching-Ho Chen Ray-Shyan Wu Wei-Lin Liu Wen-Ray Su Yu-Min Chang 《Environmental management》2009,43(1):166-188
Some countries, including Taiwan, have adopted strategic environmental assessment (SEA) to assess and modify proposed policies,
plans, and programs (PPPs) in the planning phase for pursuing sustainable development. However, there were only some sketchy
steps focusing on policy assessment in the system of Taiwan. This study aims to develop a methodology for SEA in Taiwan to
enhance the effectiveness associated with PPPs. The proposed methodology comprises an SEA procedure involving PPP management
and assessment in various phases, a sustainable assessment framework, and an SEA management system. The SEA procedure is devised
based on the theoretical considerations by systems thinking and the regulative requirements in Taiwan. The positive and negative
impacts on ecology, society, and economy are simultaneously considered in the planning (including policy generation and evaluation),
implementation, and control phases of the procedure. This study used the analytic hierarchy process, Delphi technique, and
systems analysis to develop a sustainable assessment framework. An SEA management system was built based on geographic information
system software to process spatial, attribute, and satellite image data during the assessment procedure. The proposed methodology
was applied in the SEA of golf course installation policy in 2001 as a case study, which was the first SEA in Taiwan. Most
of the 82 existing golf courses in 2001 were installed on slope lands and caused a serious ecological impact. Assessment results
indicated that 15 future golf courses installed on marginal lands (including buffer zones, remedied lands, and wastelands)
were acceptable because the comprehensive environmental (ecological, social, and economic) assessment value was better based
on environmental characteristics and management regulations of Taiwan. The SEA procedure in the planning phase for this policy
was completed but the implementation phase of this policy was not begun because the related legislation procedure could not
be arranged due to a few senators’ resistance. A self-review of the control phase was carried out in 2006 using this methodology.
Installation permits for 12 courses on slope lands were terminated after 2001 and then 27 future courses could be installed
on marginal lands. The assessment value of this policy using the data on ecological, social, and economic conditions from
2006 was higher than that using the data from 2001. The analytical results illustrate that the proposed methodology can be
used to effectively and efficiently assist the related authorities for SEA. 相似文献
396.
This research investigated the possibility of using recycled asphalt concrete as surface course in airport pavement. The basic properties of recycled asphalt binder after short- and long-term aging were firstly tested and compared with those of the virgin asphalt. Then, a series of laboratory tests were performed to evaluate the performance of recycled asphalt concrete (containing 40% and 70% RAP), in which the HMA mixture without RAP was used as a control. Furthermore, an experimental pavement consisting of three sections (corresponding to 0%, 40% and 70% RAP content) was constructed to verify the laboratory test results. These results indicated that the recycled asphalt could achieve the similar properties against long-term aging as virgin asphalt. Recycled asphalt concrete containing 40% RAP could be used as surface course in airport pavement as it exhibited similar performance as control mixture both from the laboratory and experimental pavement test results. On the contrary, recycled asphalt concrete containing 70% RAP was not recommended as its fatigue property was much poorer compared with that of virgin asphalt mixture. 相似文献
397.
环境标准实施中的若干问题 总被引:3,自引:0,他引:3
探讨了目前环境标准在制订、发行、宣贯过程中存在的问题 ,并就规范环境标准发布、加强标准宣贯等提出建议 相似文献
398.
With the development of science and technology, solid waste management has become a serious environmental problem for most communities all over the world. This paper presents a multi-objective optimization model for the management of municipal solid waste (MSW) via an uncertainty approach. In this model, the system cost of solid waste management and the environmental impact are considered as the main objectives, and some necessary constraints based on the characteristics of China are included; additionally, Pollution loss theory is applied to evaluate the environmental impact.This model is applied to the City of Fo Shan, China. Compared with the primary project of Fo Shan, which is provided by the government, the results of the optimization procedure show that the overall system cost could be reduced by $1–2.4/ton, i.e., $3.7 million/yr. The model presented in this paper was proven to be an effective response to the multi-objective solid waste management problem, and provides a new technique to optimize MSW management and operation. Why is the optimization result better? By analyzing the modelling with respect to function, constraints, and results, we conclude that the profit would be augmented due to the amount of the waste that would be treated by recycling technology, which would increase rapidly during the planning time; thus, the total system cost could be reduced accordingly. 相似文献
399.
沉淀——吸附法处理果胶工艺废水 总被引:1,自引:0,他引:1
利用果胶废水中的Al(Ⅲ)和石灰乳沉淀,并用炉渣、活性碳脱色的方法,处理盐板法提取果胶的工艺废水。通过正效实验,研究了最佳工艺条件。该工艺处理后的废水,Al(Ⅲ)去除率96.8%,CODCr去除率为92.7%,SO4^2-去除率为61.5%,且废渣产出量少。 相似文献
400.
Suñe N Sánchez G Caffaratti S Maine MA 《Environmental pollution (Barking, Essex : 1987)》2007,145(2):467-473
The aim of this work was to determine chromium and cadmium bioaccumulation processes of two free-floating macrophytes commonly used in wetlands for water treatment: Salvinia herzogii and Pistia stratiotes. Metal removal from the solution involves two stages: a fast one and a slow one. The fast stage of the Cd uptake is significantly different for each species, while it is not significantly different in Cr uptake. The most important processes of Cd uptake are biological ones in S. herzogii and adsorption, chelation and ionic exchange are in P. stratiotes. The main processes of Cr uptake in both macrophytes are adsorption, chelation and ion exchange. The slow stage is different for each species and metal. Cr precipitation induced by roots occurs in P. stratiotes. Cr uptake through leaves is probably the main cause of the increase of Cr in the aerial parts of S. herzogii. 相似文献