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41.
A pilot-scale sludge treatment plant was built to investigate the feasibility of ozonation processes for waste activated sludge treatment. Ozonation of wastewater sludge resulted in mass reduction by mineralization as well as by supernatant and filtrate recycle. Another advantage of sludge ozonation is a significant improvement of settleability and dewaterability. Experimental results showed that mass reduction of 70% and volume reduction of 85% compared with the control sludge was achieved through the sludge ozonation at a dose of 0.5?gO3/gDS. It is also interesting to note that the filterability deteriorates up to ozone dose of 0.2?gO3/gDS and then improves considerably at a higher ozone dose. The filterability could be improved by chemical conditioning even at a low ozone dose. The economic feasibility by cost analysis reveals that ozonation processes can be more economical than other alternative processes for sludge treatment and disposal at small-sized wastewater treatment plants. 相似文献
42.
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44.
赵伟 《电脑与微电子技术》2014,(11):17-19,23
在中职、高职类院校,项目式教学正在被推广,在项目式教学模式下,我们把实际的企业项目带到课堂,同时,我们也希望借鉴有益的企业对员工的评价方法。基于此,提出在原有的项目式评价学生体系下,增加对学生承诺的考核方法,并给出切实可操作的研究方案。增加对学生承诺的考核旨在充分发掘学生的潜能,对超出学生承诺的专业能力的成绩给予鼓励。 相似文献
45.
Seong-Soo Hong Gun-Dae Lee Jong-Won Park Dae-Won Park Kyung-Mok Cho Kwang-Jung Oh 《Korean Journal of Chemical Engineering》1997,14(6):491-497
In the present work, we have investigated the reduction of NO by propane over perovskite-type oxides prepared by malic acid
method. The catalysts were modified to enhance the activity by substitution of metal into A or B site of perovskite oxides.
In addition, the reaction conditions, such as temperature, O2 concentration, and space velocity have been varied to understand their effects on the catalytic performance. In the LaCoO3 type catalyst, the partial substitution of Ba and Sr into A site enhanced the catalytic activity in the reduction of NO.
For the La0.6Ba (Sr)o.4 Co1−x
FexO3 (x=0-1.0) catalyst, the partial substitution of Fe into B site enhanced the conversion of NO, but excess amount of Fe decreased
the conversion of NO. The surface area and catalytic activity of perovskite catalysts prepared by malic acid method showed
higher values than those of solid reaction method. The conversion of NO increased with increasing O2 concentration and contact time. The introduction of water into reactant feed decreased the catalytic activity but the deactivation
was shown to be reversible over La0.6Ba0.4Co1−x
,FexO3 catalyst. 相似文献
46.
47.
Pt-V2O5-WO3/TiO2 catalysts supported on SiC filter for NO reduction at low temperature 总被引:1,自引:0,他引:1
Joo-Hong Choi Jin-Hyun Kim Young-Cheoul Bak Rose Amal Jason Scott 《Korean Journal of Chemical Engineering》2005,22(6):844-851
The catalytic filter, V2O5-WO3-TiO2 supported on a ceramic filter, is known as a promising material for treating particulates and NO
x
simultaneously at optimum temperatures around 320°C. In order to improve its catalytic activity at low temperatures, the
effect of Pt addition on the catalytic filter has been investigated. Catalytic filters, Pt-V2O5-WO3-TiO2/SiC, were prepared by co-impregnation of Pt, V, and W precursors on TiO2 coated-SiC filter by vacuum aided-dip coating. The Pt-added catalytic filter shifted the optimum working temperature from
280–330°C (for the non Pt-impregnated filter) to 180–230°C, providing N
x
slip concentration less than 20 ppm for the treatment of 700 ppm NO at a face velocity of 2 cm/s with the same value over
the non Pt-added catalytic filters. The promotional effect following the addition of Pt is believed to result from electrical
modification of the catalyst maintaining a high electron transfer state. Ammonia oxidation was also observed to be dominant
above the optimal temperature for SCR. 相似文献
48.
以4-氯-2-氟-酰替苯胺为原料,经硝化,还原,重氮化,与巯基乙酸作用,水解反应制得化合物2-氯-4-氟-5-胺基苯基硫代乙酸甲酯,以4-氯-2-氟-5酰替苯胺为原料经酰化,还原,缩合制得化合物2-氯-4-氟-5-甲氧羰基硫代乙酸甲酯。通过比较2条工艺方法的优缺点确定了最佳工艺路线。 相似文献
49.
利用热天平测试了CO、H2还原饱和脱硫剂微孔内Fe2(SO4)3的起始反应温度及还原速率,用X射线衍射法分析了反应中间产物及最终产物.实验结果表明,脱硫剂还原法再生的反应温度较传统热分解法低约200℃,CO作再生脱硫剂的还原气体优于H2,CO还原脱硫剂内Fe2(SO4)3的反应级数为0.87,活化能为142.9kJ/mol. 相似文献
50.
This paper describes the design and application of the Atmospheric Evaluation and Research Integrated model for Spain (AERIS). Currently, AERIS can provide concentration profiles of NO2, O3, SO2, NH3, PM, as a response to emission variations of relevant sectors in Spain. Results are calculated using transfer matrices based on an air quality modelling system (AQMS) composed by the WRF (meteorology), SMOKE (emissions) and CMAQ (atmospheric-chemical processes) models. The AERIS outputs were statistically tested against the conventional AQMS and observations, revealing a good agreement in both cases. At the moment, integrated assessment in AERIS focuses only on the link between emissions and concentrations. The quantification of deposition, impacts (health, ecosystems) and costs will be introduced in the future. In conclusion, the main asset of AERIS is its accuracy in predicting air quality outcomes for different scenarios through a simple yet robust modelling framework, avoiding complex programming and long computing times. 相似文献