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71.
72.
简要介绍了等离子体的相关概念及其处理污染物的工作原理,阐述了等离子体技术在固体废弃物治理方面的应用研究概况,并对等离子体在固体废弃物治理中的应用作了市场前景分析,说明了该技术在固体废弃物治理中具有一定的应用前景。 相似文献
73.
DING Wei GAO Ying-xin YANG Min DING Ran ZHANG Yu 《环境科学学报(英文版)》2007,19(10):1178-1182
High strength refractory organic stream is produced during the production of 2-phenylamino-3-methyl-6-di-n-butylaminofluoran (One Dye Black 2, abbr. ODB 2), a novel heat-sensitive material with a promising market. In this study, a combination of acidificationprecipitation, primary biological treatment, Fenton's oxidation and another biological treatment was successfully used for the removal of COD from 18000-25000 mg/L to below 200 mg/L from the ODB 2 production wastewater in a pilot experiment. A COD removal of 70%-80% was achieved by acidification-precipitation under a pH of 2.5-3.0. The first step biodegradafion permitted an average COD removal of 70% under an hydraulic residence time (HRT) of 30 h. By batch tests, the optimum conditions of Fenton's oxidation were acquired as: Fe^2+ dose 6.0 mmol/L; H2O2 dose 3000 mg/L; and reaction time 6 h. The second step biological treatment could ensure an effluent COD below 200 mg/L under an HRT of 10 h following the Fenton's treatment. 相似文献
74.
75.
ZHANG Shao-yuan Renze van Houten Dick H. Eikelboom JIANG Zhao-chun FAN Yao-bo WANG Ju-si 《环境科学学报(英文版)》2002,14(4):501-507
Based on the microorganism kinetic model, the formula for computing hydraulic retention time in a membrane bioreactor system (MBR) is derived. With considering HRT as an evaluation index a combinational approach was used to discuss factors which have an effect on MBR. As a result, the influencing factors were listed in order from strength to weakness as: maximum specific removal rate K, saturation constant Ks, maintenance coefficient m, maximum specific growth rate ,ua and observed yield coefficient Yobs. Moreover, the formula was simplified, whose parameters were experimentally determined in petrochemical wastewater treatment. The simplified formula is θ= 1.1( 1/β -1)(Ks S)/KXo , for oetroehemical wastewater treatment K and Ko eaualed 0.185 and 154.2, resoectively. 相似文献
76.
应用激光粒度粒形分析仪、灰熔融性测定仪、原子吸收光谱仪和XRD等仪器手段对国内2种垃圾焚烧飞灰的密度、颗粒特性、熔点、成分和晶相结构等物理化学性质进行了详细的研究。研究发现,2种灰样颗粒直径的数量积分分布非常接近,其中基本没有超过40/μm的颗粒。由于垃圾焚烧飞灰在化学成分上存在的差异导致了其熔点有很大的不同。此外,XRD结果显示不同来源的飞灰其晶相结构存在较大的差别,这可能与垃圾的来源和焚烧工艺以及烟气处理方法有关。实验结果为飞灰无害化低温烧结工艺的选择和运行参数的制定提供了依据。 相似文献
77.
以铬渣和粉煤灰为混合填充体系的主要填料,采用柱子淋洗法,通过改变混合填料的配比来研究其对铬渣中Cr(Ⅵ)的阻留作用。试验结果表明,各种混合填充体系对Cr(Ⅵ)均有一定程度的阻留作用,其中I—5校对Cr(Ⅵ)的阻留固定效果最佳,淋出液中Cr(Ⅵ)的质量分数为0.删%,相对阻留效果达94.53%。 相似文献
78.
ABSTRACT: The time to hydrograph peak of a watershed basin has been found to correlate with various statistical attributes (e.g., skewness and kurtosis) of its hypsometric curve (treated as probability distribution). This paper presents a theoretical travel time that is conceptually analogous to the time to hydrograph peak and can be calculated directly from the hypsometric curve of a watershed basin based on gravity and acceleration. The theoretical travel times for 23 selected watersheds in the United States are found to correlate significantly with their corresponding hypsometric attributes. In addition, the theoretical travel times are consistent with the times of concentration estimated from the Federal Aviation Administration method. Thus, this paper offers a simple theoretical explanation to the empirically identified linkage between time to hydrograph peak and hypsometric attributes. This theoretical travel time can provide an alternative way of characterizing the effects of basin morphometry on hydrologic response. 相似文献
79.
80.
J. Y. Kim M.-C. Shin J.-R. Park K. Nam 《Journal of Material Cycles and Waste Management》2003,5(1):0055-0062
The effect of the soil solids concentration in batch tests on the measured values of the partition coefficient (K
p) of organic pollutants in landfill liner-soil material was investigated. Since this study was based on the results of batch
and column tests conducted independently, there were limitations to the conclusions derived. The organic compounds tested
were benzene, methylene chloride, toluene, trichloroethylene, and p-xylene. The results of this study showed that as soil solids concentrations increased, the measured K
p values of these organic compounds strongly decreased. The observed values of K
p stabilized when the soil solids concentration was above a certain value. Typical K
p values obtained from batch tests conducted under high soil solids concentrations were close to those obtained from column
tests. It was concluded that the K
p values of organic compounds measured under low soil solids concentrations, i.e., less than 100 g/l, may not correctly simulate
the field situation. Consequently, the values of K
p obtained with low soil solids concentrations can result in an overestimation of the retardation factor of the landfill liner
material.
Received: March 14, 2002 / Accepted: August 25, 2002 相似文献