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921.
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Co-production of electricity, district heat and industrial heat/process steam (heat and power, CHP) has been applied to a large, national scale, in only a few countries in the world, Denmark, The Netherlands and Finland. In this production method, the waste energy from electricity production is used in two quality levels. First, industrial process steam requirements can be met with this residual energy. Second, the waste energy is used in local district heating networks for households and other buildings in a city. In this integrated production method, a total fuel efficiency of 85% can be achieved. Through the technique of fluidized bed combustion, modern CHP plants can use coal and oil, and in addition, heterogeneous fuels such as biomass, industrial wastes and recycled fuels from households. In this paper, the CHP method is considered in terms of four categories of material and energy flows. For the purpose of considering the potential environmental gains and the difficulties of this production method when applied to integrated waste management and energy production, the four suggested categories are: matter (biomass) (1), nutrients (2), energy (3) and carbon (4). Corporate environmental management inventory tools, decision-making tools, management, organisational and administrative tools as well as information management tools that could be used in CHP-related material and energy flow management are shortly discussed. It is argued that for CHP energy and environmental management, it can be important to adopt an approach to networks of firms, rather than to an individual firm. The presented material and energy flow model may contribute to assessing, planning and implementing of CHP-based waste management and cleaner energy production. 相似文献
924.
We investigated the spatial distribution of Pb in soil and dust samples collected from 54 sites in Shenyang city, Liaoning province, Northeast China. Soil background Pb concentration was 22 mg kg−1 and control values from non-industrial areas were 33 mg kg−1 for soil and 38 mg kg−1 for dust. Soil Pb concentrations varied widely, ranging from 26 to 2911 mg kg−1, with a mean concentration of 200 mg kg−1, 9 times the background value and 6 times the control value. There was great variation in soil Pb, with a coefficient of variation (CV) of 1.06 and a standard deviation (SD) of 212 mg kg−1. Dust Pb concentrations fluctuated from 20 to 2810 mg kg−1, with a mean value of 220 mg kg−1, almost 6 times the control value. No significant differences in distribution were observed between soil Pb and dust Pb. The highest Pb concentration was observed in Tiexi district in an industrial area. Soil Pb concentration decreased with depth and with distance from the pollution source. Lead concentrations initially changed little but then decreased with distance from the roadside, and were generally higher on the east side of roads than on the west. Lead contents in different categories of urban area differed substantially with dust and soil Pb concentrations decreasing in the sequence: industrial >business >mixed (residential, culture and education)> reference areas. 相似文献
925.
优势菌处理高浓度苯胺工业废水的研究 总被引:7,自引:0,他引:7
本文叙述了从自然界分离选育出能降解苯胺的优势菌种,经人工驯化,构建出具有高效降解性能的微生物体系的试验过程,研究确立了优势菌———活性污泥组合技术工艺,并成功地将其用于含苯胺类工业废水的处理。 相似文献
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根据长江口和杭州湾北部沉积物粒度分析数据,研究表层沉积物类型、分布以及分区特征。结果表明:沉积物的分布特征受水动力条件、地貌类型以及泥沙来源等因素的综合影响,长江口表层沉积物在纵向分布上,自西向东粒径从粗到细、分选程度从好至差,在横向上自北港-北槽-南槽,沉积物粒度逐渐变细;水流动力作用强的河槽和波浪作用强的口门浅滩沉积物粒度较粗,水动力较弱的河口边滩及口外海滨区沉积物则较细。根据沉积物分布特征可将长江口及其邻近海域分为河口分汊河段沉积区、河口拦门沙沉积区、口外海滨沉积区和杭州湾北部沉积区等4个沉积区。 相似文献
929.
贵州开阳磷矿洋水矿区环境地质问题分析 总被引:3,自引:0,他引:3
由于开磷矿区地处山区,矿区自然地质条件较差,地表切割强烈,沟谷纵横,加之建矿几十年的矿山开采, 尤其是近十几年来个别乡镇企业对矿山掠夺性开采,矿区引发了一系列的环境地质问题,如山体崩塌,水土大量流失、滑坡、泥石流等地质灾害,本文通过对开阳磷矿洋水矿区环境地质问题及主要成因进行分析,提出因地制宜地采取有效措施控制、防止不良地质现象和地质作用的发生发展,合理地利用环境资源,加快对人为破坏活动的治理,稳步恢复区域生态系统的良性循环,以达到生态的最佳效益。 相似文献
930.
我国工业锅炉的爆炸事故与预防对策 总被引:1,自引:0,他引:1
工业锅炉既是应用广泛、分布面广的常见设备,又是近年来特别容易发生爆炸事故的特殊设备。分折了工业锅炉的爆炸机理和产生爆炸的原因,着重就加强对锅炉的监察,加大对“土锅炉”的查处力度,减少因设计、制造缺陷造成的事故;推进技术进步,提高锅炉安全性等能有效遏制锅炉爆炸事故的措施,从理论和实践等方面作了论述。 相似文献