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21.
土霉素废水处理的研究现状和发展趋势 总被引:2,自引:0,他引:2
回顾了土霉素废水处理的国内外进展;分析了我国现有土霉素废水处理工艺存在的问题,并在此基础上提出了回收废水中草酸和土霉素,再生化处理的工艺路线。在对工艺路线中采用的方法进行分析后,指出研究高效低耗的土霉素回收工艺是其中的关键。 相似文献
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建立了基于特征和知识的自由锻CAPP系统模型 ,论述了特征、基于知识的工艺决策等有关问题。通过总结几年来开发该系统的经验 ,从系统原理、专家系统等方面探讨了该系统的开发研制 ,并简单介绍了该系统的主要功能和特色 相似文献
24.
提出生物作用强化城市污水一级处理工艺 ,探讨利用生物絮凝吸附作用独立承担城市污水处理任务的可行性、影响因素及运行参数。试验证明 ,处理城市污水 ,当HRT为 1 1h ,DO为 1 0mg L ,CODCr污泥负荷为 3 4~ 4 0kg kg·d时 ,CODCr、BOD5和SS去除率分别为 6 8%~ 78%、6 5 %~ 72 %和 75 %~ 85 %。 相似文献
25.
采用加压活性炭生物膜法处理以对硝基甲苯磺酸盐为主的难降解的有机废水的研究,是在活性炭生物膜法处理有机废水基础上发展起来的新技术。本实验结果表明,在加压9.8×10~4Pa(1kgt/cm~2)的条件下,COD_(Cr)去除率为62%~70%,比常压活性炭生物膜法高20%~25%;其容积负荷Nv=1.7~2.9kgCOD/m~3·d,比一般活性污泥法高3~6倍。 相似文献
26.
Fan Jinhong Xu Wenying Gao Tingyao Ma Luming 《Frontiers of Environmental Science & Engineering in China》2007,1(4):504-508
Iron and copper bimetallic system (catalyzed Fe-Cu process) is a promising technology for alkaline nitrobenzene-containing
wastewater treatment. However, little is currently known about the changes of treatment efficiency with time going. This research
investigated the long-term performance of the catalyzed Fe-Cu process to reduce nitrobenzene (NB) in alkaline wastewater.
In addition, the changes of the metal surfaces morphologies and matters before and after the reaction were analyzed by scanning
electron microscopy (SEM) in conjunction with energy-dispersion spectroscopy (EDS) and X-ray diffraction spectroscopy (XRD).
The results showed that the surface properties of copper almost remained unchanged after weeks of operation, which spelled
its strong chemical stability and resistance to poisoning. Moreover, the results indicated that there were two reasons for
the treatment efficiency decreasing with time. One was the gradual iron element consumption due to corrosion. The other was
iron reactivity weakened due to the precipitates accumulation on the surfaces that were mainly Fe3O4 and FeCO.
__________
Translated from Environmental Pollution & Control, 2006, 28(10): 783–785 [译自: 环境污染与防治] 相似文献
27.
半千法烟气脱硫技术目前在国内正在快速推广应用中,但成功的实例还较少,还存在系统不可靠,技术指标达不到,故障率高等问题。介绍了循环悬浮式半千法烟气脱硫技术及首次在煤粉锅炉中应用的烟气净化新工艺:静电预除尘+循环悬浮式半干法烟气脱硫+布袋除尘,论述了净化原理及在我厂的实际应用情况。 相似文献
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29.
Georgios E. Pavlikakis Vassilios A. Tsihrintzis 《Journal of the American Water Resources Association》2003,39(2):277-288
ABSTRACT: The Ecosystem Management (EM) process belongs to the category of Multi‐Criteria Decision Making (MCDM) problems. It requires appropriate decision support systems (DSS) where “all interested people” would be involved in the decision making process. Environmental values critical to EM, such as the biological diversity, health, productivity and sustainability, have to be studied, and play an important role in modeling the ecosystem functions; human values and preferences also influence decision making. Public participation in decision and policy making is one of the elements that differentiate EM from the traditional methods of management. Here, a methodology is presented on how to quantify human preferences in EM decision making. The case study of the National Park of River Nestos Delta and Lakes Vistonida and Ismarida in Greece, presented as an application of this methodology, shows that the direct involvement of the public, the quantification of its preferences and the decision maker's attitude provide a strong tool to the EM decision making process. Public preferences have been given certain weights and three MCDM methods, namely, the Expected Utility Method, Compromise Programming and the Analytic Hierarchy Process, have been used to select alternative management solutions that lead to the best configuration of the ecosystem and are also socially acceptable. 相似文献
30.
TOPHAZOP: a knowledge-based software tool for conducting HAZOP in a rapid, efficient yet inexpensive manner 总被引:3,自引:0,他引:3
Faisal I. Khan S. A. Abbasi 《Journal of Loss Prevention in the Process Industries》1997,10(5-6):333-343
Hazard and operability (HAZOP) studies constitute an essential step in the risk analysis of any chemical process industry and involve systematic identification of every conceivable abnormal process deviation, its causes and abnormal consequences. These authors have recently proposed optHAZOP as an alternative procedure for conducting HAZOP studies in a shorter span of time than taken by conventional HAZOP procedure, with greater accuracy and effectiveness [Khan, F. I. and Abassi, S. A., optHAZOP. An effective and efficient technique for hazard identification and assessment Journal of Loss Prevention in the Process Industries, 1997, 10, 191–204]. optHAZOP consists of several steps, the most crucial one requires use of a knowledge-based software tool which would significantly reduce the requirement of expert man-hours and speed up the work of the study team. TOPHAZOP (Tool for OPTmizing HAZOP) has been developed to fulfil this need.
The TOPHAZOP knowledge-base consists of two main branches: process-specific and general. The TOPHAZOP framework allows these two branches to interact during the analysis to address the process-specific aspects of HAZOP analysis while maintaining the generality of the system. The system is open-ended and modular in structure to make easy implementation and/or expansion of knowledge. The important features of TOPHAZOP and its performance on an industrial case study are described. 相似文献