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排序方式: 共有1063条查询结果,搜索用时 203 毫秒
1.
介绍了以菱锌矿为原料生产轻质氧化锌的方法,论述了反应酸浓度,煅烧温度,溶液PH值对实验的影响,并对生产工艺条件进行了研究。其工艺流程是将粉碎后的菱锌矿进行循环酸浸,净化后再直接和碳化母液反应,经沉降后再煅烧分解为轻质氧化锌,产品质量符合国家标准,视比容大,活性强,成本低,经济效益显著。 相似文献
2.
Mushroom-like ZnO microcrystals have been prepared via a solution calcination route, using Zn(NO3)2 as Zn source in the absence of any surfactants, templates or catalysts. This is the first example to prepare mushroom-like crystals as semiconductors, which are expected to show particular physical properties. The ZnO products were investigated by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy and photoluminescence (PL) spectrum measurements. A suitable concentration of Zn(NO3)2 solution was important for the growth of the mushroom-like products. The reported synthetic procedure is straightforward and inexpensive, and thus can be readily adopted to produce large quantities of mushroom-like ZnO microcrystals. 相似文献
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活化高岭土适宜煅烧温度 总被引:2,自引:0,他引:2
影响高岭土适宜煅烧温度的因素包括煅烧时间、升温速度、煅烧气氛、炉窑、煅烧方式,生料颗粒堆集状态等,但最不可控的因素是高岭土本身的性质。任一“最佳煅烧温度”都是针对某一具体情况的。选择高岭土适宜煅烧温度既要考虑技术因素.又须兼顾经济效果。对于某种性质未知的高岭土,最简单的选择其适宜煅烧温度的方法是通过DTA/TGA来进行。 相似文献
5.
烧煤矸石的火山灰性能研究 总被引:4,自引:0,他引:4
经500-1000℃煅烧后的煤矸石,均具有火山灰活性和火山灰反应性,但煅烧温度直接影响其活性的高低和掺不同煅烧温度煤矸石的水泥强度性能。试验结果表明:试验用煤矸石经750℃温度煅烧后的活性和反应性最好,用其制得的水泥胶砂强度也最高,800℃煅烧的次之,500℃煅烧的最低。 相似文献
6.
A one-dimensional steady-state mathematical model has been developed to simulate the process of calcination of petroleum coke in a rotary kiln. A simulation is made to reproduce the operating conditions prevailing during a normal working day, in order to validate the model, and to study the effects of the main process control variables. It has been found that of the energy provided by combustion, 59.5 % comes from hydrogen, 14.6 % from the carbon of the coke bed, 13.8 % from coke dust, 11.3 % from methane and 0.8 % from tar. A comparison with existing models is made to identify eventual similarities between the various kilns under study. It appears that maximum coke temperature occurs at 45 to 55 % of kiln length, while volatile matters evolution takes place between 5 and 60 % of kiln length, measured from feed end. 相似文献
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通过对焦煅烧回窑的一些设计和运行参数的讨论,论述了锥形回转窑的设计及其使用的可行性和优越性。 相似文献
9.
Daizo Kunii 《Chemical engineering science》1980,35(9):1887-1911
A general procedure is proposed for innovative research and development of gas-solid reactor systems, with a brief explanation of the significance of each step in the procedureBased upon the contacting mode between gas and solid phases, as well as the ways of supplying thermal energy to the reacting regions, various types of gas-solid reactor systems are classified by using tables of so called “matrix” form, for thermal cracking and gasification of heavy oils, gasification of coal, gasification of solid waste, calcination of limestone, clinkering of cement and reduction of iron ore.The importance of fundamental concepts is emphasized for successful research and development by presenting several examples; namely, calcination of limestone, thermal cracking of heavy oils and gasification of solid waste materials.In connection with the direction in which fundamental research should be oriented, four primary ways of thinking are proposed, which can be applied to obtain innovative ideas for further research and development in this field.One example of the author's practical experience was selected to show the role of the fundamental research in the course of large scale development. Finally the author outlines the role of chemical reaction engineering to innovate the novel gas-solid reactor systems which may be inevitable for simultaneous solution of the three big E's; namely, Energy, Environment and Economy. 相似文献
10.
Jiaqing Li 《Electrochimica acta》2006,51(23):4942-4949
The method of Ti/TiO2 photoelectrode prepared by using laser calcination method instead of oven calcination process was introduced. The prepared TiO2 film was observed with AFM and XRD. Photoelectrocatalytic degradation of rhodamine B (RB) using this electrode was investigated, and anodic potential and pH were optimized. The laser power applied in this electrode preparation was also discussed, and it indicated that TiO2 particle prepared with high laser power was crystallized adequately and the photoelectrocatalytic ability was satisfactory. RB degradation was investigated under different conditions, and it showed that photoelectrocatalytic degradation could achieve efficient and complete mineralization of organic pollutant. The photoelectrocatalytic oxidation using the Ti/TiO2 electrode calcinated by laser was compared with that of the electrode calcinated by furnace, and it showed that the reaction rate of RB degradation using the electrode by laser was faster than that by furnace. Additionally, electrochemical impedance spectroscopy (EIS) was performed at the two different photoelectrodes, which verified the higher photocatalytic activity of the laser-treated electrode further. 相似文献