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891.
某针织印染厂年产3000吨针织高档服装布料,排放的生产废水中含有大量的有机物,COD、BOD5、色度浓度比较高。该厂选择了"厌氧水解酸化+接触氧化法+活性炭吸附"处理工艺。该工艺采用厌氧水解酸化处理工艺进行前期处理,去除大部分有机物,减轻了后续接触氧化处理工艺的压力,同时通过活性碳过滤进行脱色,达到较好的处理效果。运行结果表明,经该工艺处理后,废水中的COD、BOD5、色度等指标均能达标排放,有利于企业的可持续发展。 相似文献
892.
《International Journal of Sustainable Engineering》2013,6(1):24-36
This research work focuses on the application of life-cycle assessment methodology to determine the carbon footprint of different players involved in a supply chain of the textile sector. A case study of a product by a textile leader company was carried out. This study demonstrates that, in the textile chain, the main contribution to the greenhouse effect is provided by the electrical and thermal energy used and by the transportation (since different production phases are delocalised in a wide range that goes from South Africa, Italy, Romania and all around the world, from the distribution centre to the stores). The Monte Carlo analysis has been used in order to obtain, for each calculated impact, not only the average value but also the distribution curve of the results characterised by uncertainty parameters. Moreover, a sensitivity analysis was carried out to evaluate the impact of management choices such as: ??a change in the transportation modality, from aeroplane to boat; ??a combination of road and rail transportation; and ??a selection among suppliers that allows the firm to cut environmental impacts. 相似文献
893.
《International Journal of Sustainable Engineering》2013,6(4):232-240
A Carbon Emission Signature (CES) and a Carbon Emission Label have been proposed for manufactured products in previous CIRP (Collège International pour la Recherche en Productique) annals. This paper considers two things: (1) an example of a CES calculation for assembly with CO2 emissions and (2) the need for a transparent method of calculation. In comparing carbon footprint calculations for 17 websites, the results are found to vary more than threefold depending upon the site used and even more between different methods illustrating the need for standardisation in emission calculations for carbon accounting. 相似文献
894.
《International Journal of Sustainable Engineering》2013,6(2):132-141
Following a brief introduction about the need for businesses to respond to climate change, this paper considers the development of the phrase ‘carbon footprint’. Widely used definitions are considered before the authors offer their own interpretation of how the term should be used. The paper focuses on the contribution small and medium sized enterprises (SMEs) make to the economy and their level of influence in stimulating change within organisations. The experience of an outreach team from the Engineering Department of a UK university is used which draws on the experience of delivering regional economic growth projects funded principally through the European Regional Development Fund. Case studies are used including the development of bespoke carbon footprints for SMEs from an initiative delivered by the outreach team. Limitations of current carbon footprints are identified based on this higher education‐industry knowledge exchange mechanism around three main themes of scope, the assessment method and conversion factors. Evidence and discussions are presented that conclude with the presentation of some solutions based on the work undertaken with SMEs and a discussion on the merits of the two principally used methodologies: life‐cycle analysis and economic input–output assessment. 相似文献
895.
Abstract The Bali Roadmap, as the breakthrough on inter-governmental negotiation of climate change mitigation, having brought United States on track, is still a result of compromises. The major compromises of the Bali Roadmap are centered around three issues of quantifying emission reduction targets, developing countries’ obligations as well as quantifying developed countries’ financial assistance in developing countries’ capacity building on climate change. It is found that the rationalities behind these compromises are the national interests. Due to the fact, achieving cohesion among all nations in climate change actions is very difficult. Therefore, the Bali Roadmap may lead to a tough way with distant hope. However, technology innovation and well-designed economic instruments would be helpful and supportive for further international negotiation and cooperation. 相似文献
896.
Li Huimin 《中国人口.资源与环境(英文版)》2013,11(2):24-31
Abstract Carbon emissions embodied in international trade of China during 1997–2007 are accounted by input–output method based on Chinese input–output table and global trade analysis project database. It is revealed that carbon emissions embodied in imports and exports both increased during 1997–2007, but carbon emissions embodied in exports are greater than those embodied in imports, China is a net export nation in embodied carbon. The net exports of embodied carbon account for about 10.82% of the total carbon emissions in 1997, dropped to 7.15% in 2002, increased to 13.13% in 2006, and slightly dropped to 12.64% in 2007. Low-end position of international industry division is an objective factor of being a net exporter of embodied carbon for China, and usage of a large amount of obsolete energy-using equipments wasted much energy and increased carbon emissions embodied in exports. Importers should take more responsibilities for carbon emissions embodied in trade, and China should take a certain responsibility for unreasonable energy dissipations too. 相似文献
897.
Abstract In the context of global climate change, the internalization of negative externality, which is brought about by the traditional mode of economic growth, has become an inevitable choice. In order to achieve the internalization, it is necessary to make innovations on the market mechanism and system, find the value of environmental capital, establish a new mode of economic growth based on environmental capital, and then transform the environmental capital, an exogenous factor of economic growth, into an endogenous factor. Of this, the key of market mechanism and system innovation is the financial innovation that is based on environmental capital and negative externality; the government defines the initial property right of environmental resources and establishes environment energy trading market, so as to guide enterprises to trade environmental resources (represented by carbon emission permit trading) based on the Clean Development Mechanism, and to vigorously develop environmental finance and carbon finance. 相似文献
898.
Zhu Qirong 《中国人口.资源与环境(英文版)》2013,11(3):86-96
Abstract In this paper, using the input-output model, the author first calculated the CO2 emissions embodied in exports of China in 2002 and 2007. Then, the author empirically analyzed problems existing in the composition of exported products and analyzed its possible reasons. The research results of this paper are as follows: Since China’s entry into WTO, the CO2 emissions embodied in exports of China have been increasing rapidly; the value of exported products of high-carbon emissions industries accounts for a relatively higher proportion to China’s total exports value because China’s carbon intensive products have a certain competitive advantage. Additionally, this paper has put forward relevant suggestions based on these results. 相似文献
899.
研究已证实大气氮沉降的增加显著影响了土壤有机碳的含量,然而其变化幅度在不同的实验样地具有较大的差异.基于在我国开展的49个模拟氮沉降野外实验的408组数据,利用Meta分析、Meta回归和线性回归等方法系统研究了样地气候、土壤属性以及氮素施用参数对施氮后土壤有机碳含量的影响.结果表明,样地的年均温(MAT)和年均降水量(MAP)与施氮后土壤有机碳含量变化幅度显著正相关(P<0.05).在MAT或MAP较低(MAT<3℃,MAP<500 mm)的样地中,施氮后土壤有机碳含量显著下降;而在MAT或MAP较高(MAT>3℃,MAP>500 mm)的样地中,施氮后土壤有机碳含量则显著升高.土壤属性方面,在C:N较高(>15)或酸性(pH<6.5)土壤中,施氮后土壤有机碳积累明显(P<0.05);而在C:N较低(≤15)以及中性或碱性(pH≥6.5)土壤中,施氮后土壤有机碳变化不明显(P >0.05).此外,施氮后草原生态系统土壤有机碳含量明显下降(-5.34%);而湿地生态系统土壤有机碳含量变化不明显;森林生态系统土壤有机碳表现出明显积累(10.52%),特别是阔叶林生态系统(13.10%).所有的因子中,土壤C:N是影响施氮后土壤有机碳变化幅度的主导因子.在施氮类型方面,施加硝酸铵或尿素后土壤有机碳含量显著升高,而施加硝态氮对其影响不显著.综上所述,在精确评估、预测和分析氮沉降对土壤有机碳含量的影响时,应综合考虑样地的气候、土壤属性以及氮素施用参数等因素对实验结果的影响. 相似文献
900.
沉积物微生物是农村黑臭水体物质循环和有机物降解等过程的主要驱动者,其群落结构组成常因外界环境的微小变化而变化.以菏泽市东明县29个农村黑臭水体为研究对象,测定农村黑臭水体上覆水和沉积物氮、磷及重金属等污染物指标,结合Illumina测序结果,分析农村黑臭水体沉积物细菌群落组成和多样性特征及其与环境因子的相关性.结果表明,该区域农村黑臭水体上覆水和沉积物中污染物分布范围均较广.与农业面源相比,以农村生活污水为主要污染来源的农村黑臭水体上覆水中氮、磷污染物浓度更高,分别是农业面源的3.1倍和1.5倍.此外,该区域农村黑臭水体沉积物中重金属含量处于较低水平,普遍低于菏泽市土壤元素背景值.该区域农村黑臭水体沉积物细菌群落的优势菌门为变形菌门、放线菌门、绿弯菌门、厚壁菌门和酸杆菌门,这5种优势菌门的序列总和占全部序列的70.3%~83.6%.γ-变形菌纲、α-变形菌纲、厌氧绳菌纲和放线菌纲是沉积物细菌群落的优势菌纲;硫杆菌属和假节杆菌属是其优势菌属.Spearman相关性分析结果表明,环境因子中DO、 COD、 TN、 TP和有机质对农村黑臭水体沉积物细菌菌属有显著影响(P<0.05),沉... 相似文献