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51.
硫磺回收装置的设备需要有较大的操作弹性。针对其过程气进口压力低,手工计算难于进行严格的全程压降计算,现以PRO/Ⅱ软件为开发平台,通过扩充数据库和建立模拟流程,成功地将其用于硫磺回收装置的设备选型和核算,为工程设计提供了先进的计算手段。 相似文献
52.
Chuan-Kun Liu 《Desalination》2004,169(2):185-192
Electroplating method was employed to recover copper and surfactant simultaneously from synthetic solutions prepared to simulate concentrated waste stream generated from micellar-enhanced ultrafiltration. Effects of surfactant and copper (II) concentrations, surfactant to copper (II) molar ratio (S/M), electroplating voltage and time, solution pH, and ionic strength on metal recovery and electrical current efficiency were investigated. Results show that at a fixed S/M ratio of 5, the first-order kinetic constant for Cu (II) removal by electroplating increases with decreasing SDS concentration. At fixed SDS concentration of 8.5 mM, increasing initial Cu (II) concentration increases both Cu (II) recovery and current efficiency. Electrolyte pH has profound effects on the metal recovery and current efficiency due to the difference in solution conductivity after pH adjustment and the extent of Cu (II) adsorption onto SDS at different pHs. 相似文献
53.
测定了60℃和2-600bar时由CO2和He、Ar、SF6以及CHF3组成的等分子二元混合物的压缩因子,根据纯物质和混合物的压缩因子计算了压力混合效应和过剩体积。对于真实气体混合性质的描述,本文采用五参数的BACK方程,方程计算值与实验值符合较好。 相似文献
54.
K Harmsen 《Nutrient Cycling in Agroecosystems》1984,5(4):371-382
Agronomic efficiency (AE) is defined as the increase in economic yield of a crop per unit fertilizer applied. Components of AE are physiological efficiency and apparent recovery fraction. The latter can be further separated into uptake efficiency and availability index. Ways to increase the nitrogen fertilizer use efficiency in rainfed agriculture through fertilizer management are discussed. 相似文献
55.
基于Smtp和Pop3的邮件还原技术已经日臻成熟,而由于主要Webmail邮件格式不同,Webmail邮件还原技术一直是难点。通过对主要Webmail的内容格式分析,针对不同网站的Webmail建立相应的还原模块,实现对主要Webmail的内容还原。实验结果验证了该技术的有效性。 相似文献
56.
57.
The hydrodynamic and gas mixing characteristics have been determined in a FCC regenerator (0.48 m I.D.x3.4 m high) with FCC
particles. Solids holdup in the dense bed decreases with increasing gas velocity, but it increases in the freeboard region.
The bubble/void fraction increases with an increase along the bed height at a given gas velocity and increases with increasing
gas velocity at a constant bed height. Backmixed tracer gas at the wall region is higher than that at the center region of
the bed. The gas backmixing coefficient decreases with increasing gas velocity. 相似文献
58.
本文介绍了丙烯腈生产过程中影响杂质噁唑产生的因素,并对噁唑超标的处理方法进行了研究,成功地将侧线产品中噁唑的含量控制在10^-6之内。 相似文献
59.
The characteristics of gas bubbles in a 5 cm diameter bubble column equipped with a single orifice of 1,3 or 5 mm diameter were investigated under system pressure of 0.1-15 MPa. The formation of gas bubbles was strongly affected by the system pressure. Under high pressures a dispersed gas jet was formed at gas velocities where spherical gas bubbles would have been formed at atmospheric pressure. The critical gas velocity between the bubbling regime and the jetting regime was correlated with the liquid phase Weber number and the gas phase Reynolds number based on the gas velocity at the orifice. Bubble size and gas holdup in the main part of the bubble column were also affected by the bubble formation pattern at the distributor 相似文献
60.
A methodology for studying the kinetics of gas-solid reactions in a fluidized bed reactor is presented. This procedure is based on the analysis of the response of the system (flue gases) when batches of solids of different weight are added to the reactor. The method has been applied to the study of limestone particle calcination. The calcination rate constants obtained are in good agreement with those found in the literature. The method offers the advantage of simplicity and avoids the use of model assumptions or empirical correlations. 相似文献