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101.
氨氮与亚硝酸盐比对推流式ANAMMOX反应器影响研究 总被引:1,自引:0,他引:1
进水基质中NH3-N与NO2--N比例是影响推流式ANAMMOX反应器性能的重要参数。该比例与NH3-N、NO2--N、TN的去除率以及NH3-N与NO2--N的反应比例等参数呈良好的相关性。在同一进水TN负荷条件下,存在一个最佳的进水比例,使TN去除率达到最大。NH3-N和NO2--N的反应比例随着进水基质比例的变化而变化。在反应器中发生的ANAMMOX反应可能有多种含氮的产物形式(不仅是N2一种)。进水基质比例的变化可能会导致ANAMMOX反应复杂化,多种反应途径同时并存。 相似文献
102.
对尿素合成塔上封头腐蚀凹坑采用中国SAPV-95和美国API579规范分别进行安全评定,给出安全裕度,简略分析安全评定的结果。 相似文献
103.
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105.
K. Scott 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,54(3):257-266
This paper presents a relatively straightforward approach to the modelling of electrochemical reactors operated in batch or continuous modes. The models are based on ideal flow assumptions of either well-mixed or plug flow and incorporate reaction rate models based on electrochemical kinetics and mass transport at one electrode. General characteristics of the reactor models are described, particularly with regard to the need for good mass transport in metal recovery applications. An example is given on the use of the model in the recovery of a heavy metal (Cd2+) from an acidified solution containing Cd(II) and Fe(III) ions. The reaction rate model is based on experimental data. 相似文献
106.
The effect of batch and semi-batch additions of the stoichiometric amount of H2O2 on enzymatic removal of phenol has been studied over the phenol concentration range of 1-10 mmol/L. It is found that the ratio between the maximum H2O2 concentration during the reaction and the initial horseradish peroxidase concentration ((H2O2)max/(HRP)o) controls the rate of phenol removal by horseradish peroxidase in the presence of the additive, polyethylene glycol. An optimum range of this ratio is determined to be between 10 and 25 μmol/U. Empirical models are proposed to predict the values of (H2O2)max/(HRP)o required to treat given phenol concentrations under different modes for adding H2O2. 相似文献
107.
108.
反应器网络综合优化方法的研究进展 总被引:3,自引:0,他引:3
反应器网络综合优化方法在选择反应器类型和反应工艺条件时,比传统的方法表现出了很大的优势。综述了各类反应器网络综合优化方法的基本原理和研究进展,并分析了它们的优缺点。这些方法有基于过程特征的方法,包括可得区法和导数分析法;超结构优化法;目标类方法,包括目标法、构造目标法和构造MINLP法;以及经验推断法和分布参数法等。最后分析了这方面研究的发展趋势。 相似文献
109.
Jichen Qin 《Chemical engineering science》2006,61(18):6154-6164
A model of continuous melt transesterification of bisphenol-A and diphenyl carbonate in a continuous stirred tank reactor is developed using phase equilibria assumption and the method of molecular weight moments. The model equations can be simplified into a polynomial system that has 17 equations and 17 unknowns. Solution of the polynomial system gives out almost every aspects of the continuous transesterification process. Molecular weight and polydispersity index, end group ratio of hydroxyl to phenyl carbonate, contents of molecular species, and lost diphenyl carbonate fractions are studied in different operation parameters. 相似文献
110.
I.Z. Ismagilov R.P. Ekatpure L.T. Tsykoza E.V. Matus E.V. Rebrov M.H.J.M. de Croon M.A. Kerzhentsev J.C. Schouten 《Catalysis Today》2005,105(3-4):516-2
This paper describes the optimization of three processes applied in fabrication of a microstructured reactor for complete oxidation of volatile organic compounds. The first process involves the optimization of the electro discharge machining (EDM) method to produce a set of microchannels with a high length to diameter ratio of 100, with a standard deviation from the average diameter below 0.2%, and with a surface roughness not higher than 2.0 μm. To satisfy these criteria, fabrication of microchannels must be carried out with two machining passes in the Al51st alloy. Then, the effect of several parameters on the anodization current efficiency with respect to oxide formation was studied. The best process conditions to get a 30 μm porous alumina layer in a 0.4 M oxalic acid electrolyte, were found to be a temperature of 1 °C, an anodic current density of 5 mA/cm2, and 23 h oxidation time. At last, the resulting coatings were impregnated with an aqueous solution of copper dichromate followed by drying and calcination at 450 °C to produce active catalysts. The effect of a copper dichromate concentration, number of impregnation cycles (1 or 2), and different after-treatments on catalytic activity and stability in complete oxidation of n-butane were studied. The catalytic activity of the obtained coatings is superior to that of alumina supported pelletized catalysts even at much lower loadings of active metals. 相似文献