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991.
清洁生产在企业实施过程中面临的主要问题及对策 总被引:1,自引:0,他引:1
从1989年联合国环境署(UNEP)首次提出清洁生产的概念,到1999年国家进行清洁生产试点,并于2003正式实施《中华人民共和国清洁生产促进法》,清洁生产已成为中国企业污染防治工作的重要内容.实践表明:清洁生产的推行虽然取得了一定的成果,但由于缺乏相应的实施清洁生产的政策、法规、资金、技术等,当前企业清洁生产的实施进展得还比较缓慢.要进一步推行清洁生产,还需要完善制度,制定一定的对策,如:落实清洁生产优惠制度,大力研发清洁生产技术,完善相应的法规和政策等.只有这样,才能使企业积极、主动、长久地推进和实施清洁生产. 相似文献
992.
以高温厌氧细菌热纤维梭菌(Clostridium thermocellum LQRI和VPI菌株)和嗜热厌氧乙醇菌(Thermoanaerobacterethanolicus X514和39E菌株)为对象,以不同浓度纤维素为底物,分析了热纤维梭菌不同菌株的纤维素降解和酒精生产能力.结果表明,在热纤维梭菌纯培养体系中,LQRI对纤维素的降解能力明显高于VPI,前者约为后者的1.2倍,但两者的酒精生产能力没有显著差异,LQRI在1%纤维素条件下酒精终浓度约为12 mmol/L,VPI约为10 mmol/L.随着底物纤维素浓度的增加(1%、2%、5%),两者对纤维素降解和酒精生产能力均呈明显下降趋势.在热纤维梭菌和嗜热厌氧乙醇菌混合培养体系中,LQRI对纤维素的降解能力明显高于VPI,前者约为后者的1.28~1.58倍.随着底物浓度的增加,两者的纤维素降解率均逐渐下降,但热纤维梭菌对纤维素降解的绝对数值还受到其它混合培养菌种的影响.此外,LQRI+Thermoanaerobacter混合培养体系的酒精生产能力明显高于VPI+Thermoanaerobacter,前者约为后者的1.27~1.77倍.随着底物浓度的增加,混合培养体系酒精生产能力没有明显下降趋势. 相似文献
993.
994.
Vesna Zupanc Martina ŠturmSonja Lojen Nina Marši?-KacjanJoseph Adu-Gyamfi Branka Bra?i?-?eleznikJanko Urbanc Marina Pintar 《Agriculture, ecosystems & environment》2011,144(1):167-174
In the search for new technologies that would ensure optimum yield and environmental sustainability, various irrigation, nitrogen and cropping system management strategies for the production of vegetables with a shorter growing period were assessed at a benchmark site in Slovenia for the years 2006 and 2007. In the studied years four irrigation and fertilization treatments were applied: (1) 50% drip irrigation of plants water requirements ETcrop and the farmer's practice of fertilisation (broadcasting), (2) fertilisation and 100% drip irrigation (fertigation), (3) the farmer's practice of irrigation (sprinkler irrigation using water stored in plastic tanks) and fertilisation, and (4) control (the farmer's practice of irrigation but no fertilisation). An equivalent of 80, 80 and 200 kg ha−1 of nitrogen (N), 50, 50 and 80 kg ha−1 of phosphorous (P) and 120, 120 and 300 kg ha−1 of potassium (K) was added for iceberg lettuce, endive and cabbage, respectively. Nitrogen (N) labelled fertilizer (15N) was applied to trace the movement of the applied N fertiliser. The tested irrigation and fertilisation techniques for the production of vegetables with a shorter growing period in the Slovenian climate showed that environmentally sustainable practices (split application of nutrients compared to broadcast incorporating fertilisation) should be a practice of choice in water protection zones. The results confirm that fertigation and improved irrigation scheduling can be an effective way of minimizing nitrate leaching, and should be considered for vegetable production in or close to groundwater protection zones. 相似文献
995.
Bozena Guziana 《Journal of Cleaner Production》2011,19(8):827-835
The Environmental technology (ET) sector delivers environmentally preferably products. Little is known about whether companies in the ET sector set environmental objectives relating to their own production processes. This paper presents results from an online survey on environmental work in enterprises listed by the Swedish Environmental Technology Council (Swentec). The survey found that depending on the specific subsector, only between 21% and 45% of companies provide information about their environmental work on their website. This paper proposes environmental aspects of production and products as bases for corporate greening and for defining ‘green’ and ‘green-green’ business and identifies three main motivations for the companies within ET sector to operate as ‘green-green’ businesses: ‘competitive advantage’, ‘environmental responsibility’ and ‘environmental leadership’. 相似文献
996.
C. Strazza A. Del Borghi M. Gallo M. Del Borghi 《Journal of Cleaner Production》2011,19(14):1615-1621
The objective of this paper is to assess the environmental effectiveness of a strategic measure aimed at resource productivity enhancement. The cement industry has been identified as a relevant sector for this global issue, since the related production process enables the use of waste in partial substitution of raw materials and in substitution of traditional fuels. The analysis of the cement production sector in Italy has been here performed, investigating the recovery of energy from waste through co-incineration. In terms of air emissions, the emission performances of cement kilns appear independent from the use of alternative fuels at the percentages usually employed. However, in order to measure the cleanliness of a production system, systematic analysis with global perspective is needed. For this aim, the principles of Life Cycle Assessment (LCA) have been used for a case study analysis of an Italian active plant using an amount of recovered plastics as an alternative fuel resource. The improvement on the investigated process has been quantitatively measured as a way for cleaner production, first in terms of gross energy requirement, and then through an environmental performance comparison with a sector benchmark. The analysis has highlighted the benefits on the global environmental balance for the practice of co-incineration in the cement production process. 相似文献
997.
Polybrominated diphenyl ethers (PBDEs) were measured in atmosphere and soil samples taken in winter and summer at a PBDE
production area of Laizhou Bay in China. The concentrations of P11PBDE were 0.017–1.17 ng/m3 in gaseous phase, 0.5–161.1 ng/m3
in particulate phase, and 73–2629 ng/g dry weight in soil samples. The PBDE congener pattern in the gaseous phase di ered from that
in the particulate phase, and the PBDE congener pattern in the particulate phase was similar with that in soil. This demonstrated that
there was little di erence with atmospheric particle-soil transfer e ciency among PBDE congeners. In addition, there were seasonal
variations in percentages on particle for lower brominated congeners. The BDE-28 was mostly in the gaseous phase in summer (88.3%),
whereas the average proportion of BDE-28 in gaseous phase in winter was 38.9%. Higher brominated congeners (i.e., BDE-206, BDE-
207, BDE-208, and BDE-209) were bound to the atmospheric particulate phase, and their potentials for long-range migration were
mainly a ected by the environmental behavior of atmospheric particles. Results indicated that PBDE congeners in summer were closer
to gas-particle partition equilibrium than in winter. Temperature should be considered the main factor causing nonequilibrium in winter. 相似文献
998.
以马铃薯淀粉生产中产牛的废渣为主要原料,黑曲霉为发酵菌种,采用固体发酵方法,通过单因素实验,研究了马铃薯渣初始含水量、碳源、氮源、接种量等不同因素对产酶的影响,确定了马铃薯渣发酵产生复合酶的最佳条件为:马铃薯渣初始含水量为50%,马铃薯渣:麸皮=6:4,硫酸铵添加量2.0%,接种量为5%,发酵时间3 d.在优化条件下,... 相似文献
999.
开展清洁生产环保对标工作是峰峰集团实现建设绿色矿区、和谐矿区、富强矿区的重要途径,为了实现企业经济结构转变、提高企业污染防治水平、提高企业资源综合利用,峰峰集团从2008年至今,紧紧围绕国家清洁生产环保先进水平的标准,全面推行实施清洁生产审核,开展了在资源综合高效利用、降低污染物排放等方面的环保对标和实践工作,"废物"资源利用指标也达到了国内同行业清洁生产先进水平,通过清洁生产环保对标工作的实施,不仅改善了环境,实现了绿色开采,同时又促进了企业的和谐发展、科学发展。 相似文献
1000.