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811.
针对当前中小城市污水处理厂设计中存在的厂址选择不合理、处理工艺盲目求新求变、设备选择不切合实际等问题进行探讨,结合已建成污水处理厂运行实际进行分析,提出优化厂址选择、结合当地实际选择处理工艺、根据需要选择设备等解决问题的办法。 相似文献
812.
A benthic in situ flume and a 1D biogeochemical sediment model to evaluate solute fluxes across the sediment–water interface have been developed.
The flume was successfully used to determine oxygen and nutrient fluxes at various locations of the Neckar River in Germany.
The experimental results were linked with vertical pore water concentration profiles and independently verified with the model.
By combining experimental and model results we assessed the influence of dissolved oxygen concentrations in the water column
and the availability of degradable organic matter on sediment oxygen demand. The results and the derived relations can be
used to parameterize the sediment module of large scale water quality models, allowing one to assess the influence of sediment–water
interactions on various aspects of river water quality. Moreover, the biogeochemical sediment model can help to improve the
general understanding of the processes governing solute concentrations and fluxes in sediments and across their interfaces. 相似文献
813.
结合某污水处理场的情况,提出了对高浓度混合污水处理工艺进行改进的方法,对炼油、化工废水处理场进行了优化管理。分析了影响污水治理的因素,提出了改进措施。实施改进方法以后,提高了污水处理抗冲击能力和治理效果,使污水处理场实现了长期平稳运行。 相似文献
814.
James D. Womack J. Clement Burdkick Floyd C. Larson 《Journal of the American Water Resources Association》1973,9(1):100-115
ABSTRACT. As a result of several investigations conducted in the Department of Civil Engineering through the Water Resources Research Center at The University of Tennessee, dating from 1966 to the present, a rather comprehensive surveillance of water quality conditions has been maintained in Forth Loudoun Reservoir on the Tennessee River near Knowville, Tennessee. During the period covered by these investigations, the Knoxville Third Creek Sewage Treatment Plant was upgraded from a primary plant to a secondary (activated sludge) treatment plant. Comparison of the collected data is being undertaken herein to elucidate the impact of these modifications upon water quality conditions in the reservoir. Consideration is given to the improvements of water quality as related to the expenditure for modification of the treatment facilities. In addition, comment is directed toward the public health significance of the water quality conditions determined. 相似文献
815.
816.
817.
Elena A. Zakharova Paul V. Kosterin Vitaly V. Brudnik Alexander A. Shcherbakov Alexander A. Ponomaryov Lubov F. Shcherbakova Vladimir G. Mandich Eugenii E. Fedorov Vladimir V. Ignatov 《Environmental science and pollution research international》2000,7(4):191-194
A plant-based bioremediation (phytoremediation) strategy has been developed and shown to be effective for the clean-up of
soil contaminated by the breakdown products of the chemical warfare agent (CWA), yperite. The method involves exploiting the
plant growth hormone, indole-3-acetic acid (IAA), to intensify the phytoremediation. For determination of the yperite breakdown
products, gas chromatography is used.
Soil and plant samples were analysed with a gas chromatograph fitted with an atomic emission detector. The method of standard-free
determination was employed to identify sulphur-containing substances (SCSs). A series of soil tests was conducted, which showed
that the level of SCSs decreased 4, 8, and more than 20-fold compared with that found in contaminated soil. This decrease
was dependent upon the IAA concentrations used for plant treatment. The treated plants accumulated 2.7 to 2.9-fold larger
amounts of the SCSs than did the untreated plants. Owing to its simplicity, environmental safety and inexpensiveness, the
method can be recommended for the restoration of soil fertility in areas of storage and destruction of blister CWAs. 相似文献
818.
洪水、地震、泥石流、台风等不可抗力对工厂安全造成威胁,因此厂址选择阶段如何考虑不可抗力因素,如何处理不可抗力因素与其它建厂条件间的关系十分重要.提出如何避免或减小不可抗力对工厂安全的威胁,并列举工程实例进一步说明处理方法. 相似文献
819.
燃煤火电厂汞排放因子测试设计及案例分析 总被引:11,自引:6,他引:5
在火电厂锅炉煤的燃烧中,汞的迁移是个复杂的过程.在炉内高温下,几乎所有的汞以气态形式停留于烟气中,随着烟气温度的降低,汞被再分配到粉煤灰、炉渣和空气中.采用测试和衡算的方法,对火电厂汞排放因子进行测试和分析.结果表明:汞的迁移分配与煤中汞的赋存量、粉煤灰中可燃物碳的含量及烟气温度相关.煤燃烧后,进入粉煤灰中的汞占煤中汞含量的12.7%~31.3%,进入炉渣中的汞占0.9%~12.8%,大部分汞排入大气中,占67.8%~82.2%. 相似文献
820.