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991.
300 MW机组电袋组合式除尘技术的应用 总被引:1,自引:0,他引:1
为满足环保要求,保证脱硫设施的安全运行,洛河发电厂对2号锅炉电除尘器进行改造.即保留原电除尘壳体,1电场仍采用电除尘方式,将原2电场、3电场、4电场改为布袋除尘方式.实际应用结果表明,电袋组合方式除尘技术可满足除尘器出口含尘浓度低于50 mg/m3的环保要求,相对于增大原有电除尘空间的改造方案,可节省投资约200万元,节省电费约187.55万元,经济效益显著. 相似文献
992.
The effect of chlorine and oxygen concentrations on the removal of mercury at an FGD-batch reactor 总被引:2,自引:0,他引:2
A series of laboratory scale experiments were conducted in an FGD-batch reactor. A synthetic flue gas was produced and directed through a CaCO3 suspension contained in a glass reactor vessel. The suspension temperature was set at 54 °C through a water bath. In order to observe the distribution of mercury species in the system, solid, liquid and gaseous samples were taken and analysed. For gaseous mercury determination, continuous measurements were carried out, up and downstream the reactor. Furthermore, the concentration of chlorine in the scrubber solution of the system was varied from 0 to 62 g/l under different oxidative conditions.In a first approach, a concentration drop of elemental mercury coming out of the system was observed. The latter occurs only when high concentrations of Cl− are present, combined with a high O2 availability in the scrubber. It was also observed that mercury species distribution in the different phases varies, depending on the available chemical form of chlorine and oxygen concentration. 相似文献
993.
Alkaline and acidic media have been used in the textile dye industry, depending on the fabric nature. The bioremoval of textile direct violet dye by Aspergillus niger fungal strain was studied. The effect of pH on dye bioremoval was investigated at a pH range from 2 to 11. The direct violet dye bioremoval reached maximum with 92.4%, 64.0%, 91.4%, and 62.3 % at pH values of 2, 3, 8, and 9, respectively, at 24 h of incubation. The percentages of removal rate after 72 h incubation were 98.9, 97.3, 94.0, 95.0, 97.0, and 97.3 at pH 2, 3, 6, 7, 8, and 9, respectively. The optimum pH values were 2, 3, 8, and 9 for direct dye removal. At the end of the experiments, the treatment with fungal strain could reduce COD value of synthetic dye solution by 76-91%. Pseudo first and second order kinetic models were applied to evaluate differences in the biosorption rates and uptakes of textile dye. Pre-equilibrium biosorption of direct violet dye onto fungus under different dye concentrations followed a pseudo second order kinetic model with a high degree of correlation coefficients (R2 > 0.99), and the calculated values of qe nearly matched the experimental values of textile dye during the biotreatment process. 相似文献
994.
Yue Jia Rong Wang Anthony G. Fane 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2009,155(1-2):155-160
Part I of this study presents a theoretical method combined with experiments to determine the adsorption kinetics of powdered activated carbon (PAC) in the hybrid PAC-submerged membrane (SM) system with air bubbling for trace organics removal. The homogeneous surface diffusion model (HSDM) was applied to describe the kinetics of the adsorbate uptake. The differences between the model solutions and the corresponding experimental results were minimized by means of Levenberg–Marquardt algorithm so that two kinetic parameters DS and kf involved in HSDM were obtained simultaneously. The DS was found to be 1.14 × 10−16 m2/s and the kf value was correlated with the bubbling rate (Qb) and carbon dosage (Cc), which are required in the modeling of the hybrid PAC-SM system presented in Part II of this study. The kf was enhanced from 1.18 × 10−4 to 4.18 × 10−4 m/s when the bubbling intensity increased in the intermittent bubbling tests, suggesting that from energy consumption point of view, the high intensity intermittent bubbling is more efficient in improving the liquid film mass transfer than continuous bubbling with the same net bubbling rate. 相似文献
995.
基于木马程序防范技术的探讨 总被引:1,自引:0,他引:1
木马程序作为黑客常用的一种工具软件,常常以用户权限的方式运行并可控制主机的一切,其危害之大可想而知。本文主要从木马程序攻击原理和攻击手段入手进行分析,并提出了相应的清除方法和防范措施。 相似文献
996.
污水生物脱氮工程技术参数的优化设计 总被引:2,自引:1,他引:1
对<室外排水设计规范>(GB 50014-2006)中有关污水脱氮工程中技术参数的计算方法及其设计进行了分析和讨论.以设计进水水质为基本条件,介绍了硝化、反硝化池容及其参数的优化设计方法,可供相关人员参考. 相似文献
997.
对IEEE802.14物理层草案A型下行流编码方案和FEC帧同步方案进行了详细分析给出了可执行的方案并从理论上分析和计算了在64QAM调制下该编码方案传输数据所占用的带宽和误码率 相似文献
998.
介绍了一种简单实用的汽轮机不开缸除钠盐方法——灌水泡洗法,该方法在平顶山天源盐化有限责任公司1^#、2^#汽轮机应用获得了成功,并取得良好的效果。 相似文献
999.
1000.
David Hall Caroline S. B. Fitzpatrick 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2000,80(1-3):197-201
Rapid gravity, granular media filters are widely used in the water and wastewater treatment industries. Regular backwashing to clean the filters is a vital part of their efficient operation. Experimental data on the development of suspension concentration profiles through laboratory scale filter beds during the backwash process were obtained. Previous attempts to obtain and record backwash profiles of this type have been unsuccessful due to the limited range of existing turbidimeters. The results have been used to validate a new model developed by the authors. 相似文献