黄磷矿渣的粉磨动力学研究

采用φ500mm×500mm试验球磨机对黄磷渣进行不同时间的粉磨加工,运用线性回归分析、Rosin-Rammlar-Bennet(RRB)粒度分布分析和粉磨动力学的特征粒径分析的方法,对黄磷渣进行了粉磨动力学研究和粉磨性能评价。结果表明:磨后黄磷渣粉体的比表面积、特征粒径和均匀系数与粉磨时间的对数或双对数呈线性关系,且黄磷渣的加工细度不宜高于350 m2/kg。     

现代水泥工业中高效节能的粉磨技术

从粉磨系统与设备、高性能助磨剂和高效粉磨技术的选用等方面阐述现代水泥工业高效节能粉磨技术的最新进展,指出采用优化改进现有粉磨系统(如新增预粉磨或细破碎、开路改闭路、选用高效选粉机等)、选用新型粉磨设备(如辊压机、立磨和筒辊磨等)及其多种粉磨设备的组合系统、合理使用高性能水泥助磨剂、从技术和经济角度选择最适宜的粉磨技术等措施,是当今水泥工业节能降耗、优质高产的关键技术途径,可实现显著的经济效益和社会效益。     

粉磨工艺对赤泥胶结充填料性能的影响

为提高胶结充填材料的强度性能,试验研究了分别粉磨和梯级粉磨工艺对赤泥全尾砂胶结充填材料强度性能、粉体粒径以及水化过程的影响.结果表明：梯级粉磨工艺下试块的1、3、28 d最大抗压强比分别粉磨工艺下试块1、3、28 d最大抗压强度分别高出21%、16.6%、3.7%;梯级粉磨工艺使物料粉体的比表面积均高于分别粉磨工艺的粉...     

有机物助磨剂对矿渣粉磨的影响

为了研究有机物碳链长度、基团数目和种类、分子量大小对矿渣粉磨的影响,采用醇类、醇胺类、磺酸盐类有机物作助磨剂,通过测量矿渣粉体比表面积、筛余、休止角,研究有机物中不同基团对矿渣粉磨的影响。结果表明:如果碳链长度相似,所含活性基团越多,粉磨效果越好;活性基团数目相同,碳链越长,粉磨效果越差;分子量大的粉磨效果不好。其中对粉磨矿渣效果来说,丙三醇三乙醇胺磺酸盐类。     

辊式磨作为水泥预粉磨设备的优越性

通过将辊式磨预粉磨系统和洪堡辊压机半终粉磨系统在粉磨机理、效率、电耗、辊压等性能和投资方面的比较 ,认为辊式磨预粉磨系统比洪堡辊压机半终粉磨系统更适合于水泥粉磨     

饮用水处理用活性炭废炭的粉磨能耗

利用水厂活性炭废炭和行星式球磨机分别进行废炭干、湿法粉磨实验,激光粒径仪测定粉磨产物的粒径d_(50)值,在罗辛-拉姆勒粒径特性方程基础上研究干、湿法粉磨方式和磨机转速对产物d_(50)值和能耗的影响,建立废炭粉磨能耗模型,并用实际能耗值对模型进行验证。结果表明,干、湿法粉磨条件下,随能耗增加,产物d_(50)值和粒径模数均先减小后趋于平缓;在200~300 r/min转速范围内,浆料质量比为40%的湿法粉磨较干法粉磨易获得更小d_(50)值、比能耗更低、粒径分布范围更窄的粉磨产物;粉磨方式、磨机转速均影响废炭粉磨能耗;以罗辛-拉姆勒粒径特性方程为基础的能耗方程适用于行星式球磨机粉磨废炭过程。     

卧式行星磨内物料的粉磨特性

利用自制卧式行星磨对钢渣及水泥熟料进行粉磨特性及粉磨动力学研究。结果表明,粉磨后物料都满足Rosin-Rammler-Bennet粒度分布规律,钢渣及水泥熟料粉磨过程都可用一级Kapur函数描述,钢渣的粉磨速率小于水泥熟料的;在实验条件下,相对于水泥熟料,钢渣破碎更多地表现为摩擦破碎方式;钢渣进料粒级对粉磨后所得到产品的概率影响较大,粉磨前可将钢渣预破碎至粒径为1.7 mm。     

锰渣掺合料对砂浆收缩性能的影响

锰铁高炉废渣研磨后,勃氏法测得比表面积为5400cm2/g.磨细锰渣掺合料以15%和30%替代水泥,制作砂浆试件并测试干燥收缩值,同时试验了激发剂对锰渣水泥试件收缩值的影响.结果表明,锰渣掺合料会使砂浆试件的收缩增大,锰渣掺量愈多收缩值愈大.S激发剂促使锰渣水泥砂浆试件早期收缩增大.试验结果对锰渣掺合料用于混凝土结构中的收缩与抗裂性能具有参考意义.     

粉磨方式对粉煤灰理化特性的影响

为提升粉煤灰综合利用效率,采用球磨机和蒸汽动能磨对粉煤灰进行粉磨,对比2种粉磨方式所得粉煤灰的粒度、比表面积、活性指数、球形颗粒余量、物相组成和化学组成等特性,以及2种粉磨方式的能耗与粉磨效率。结果表明:与球磨机相比,通过蒸汽动能磨所得的粉煤灰微粉的粒度更小,中位径达2.25μm,比表面积可达1 110.5 m~2/kg,粉煤灰的活性指数更高,最高可达107.7%;蒸汽动能磨和球磨机不会改变粉煤灰的物相组成,但会降低粉煤灰中矿物结晶度;随粉磨强度的增加,粉煤灰粒度减小,晶体结晶度降低;粉磨破坏粉煤灰微珠颗粒,释放出内部Ca、 Si、 Al等成分,提升Si、 Al释放率,优化粉煤灰微粉的化学组成,强化水化反应;蒸汽动能磨的粉磨效率更高、耗能更少。     

破碎粉磨设备的现状及发展

介绍了破碎粉磨设备的研制现状，着重阐述了其结构、原理及适应范围，同时对今后破磨设备的发展作了评述。     

Effect of ball mill grinding parameters of hydrated lime fine grinding on consumed energy

The influence of several grinding parameters such as charged material volume, ball filling ratio, and mill rotation speed on energy efficiency of fine grinding of hydrated lime and the product fineness of hydrated lime was studied experimentally using a laboratory scale ball mill. The product size and surface area of the ground samples were determined with respect to the above variables, and changes in energy input during the grinding were described in detailed. Finally, the optimum conditions for the grinding of the hydrated lime with the ball mill were obtained. The results from this study showed that the ball mill load and mill speed are the most important parameters rather than ball mill charged material volume for the fine grinding of the hydrated lime using the ball mill in terms of energy efficiency associated with external surfaces.     

热力粉碎石英的粉磨特性

为了提高石英矿的粉磨效率,采用天然石英矿为原料,系统地研究热力粉碎石英矿的粉磨特性。结果表明,热力粉碎能够改变石英矿的物理结构,大幅度降低矿块的硬度,显著提高石英的粉磨效率;影响石英热力粉碎效果的主要因素有煅烧温度、煅烧时间和煅烧粒度,煅烧温度大于600℃后可以实现石英的有效粉碎,以800~900℃为宜,煅烧粒度越小,其粉磨效率越高,煅烧时间与矿块的尺寸有关,其长短由石英矿块内外温度达到平衡的时间来确定;热力粉碎石英与未经热力粉碎的石英相比,不仅大大提高了磨矿效率,而且磨矿产品的粒度分布更窄、更细、更均匀。     

Effect of manganese on the superconductivity of aluminum

The superconducting critical fields of pure aluminum and of two AlMn alloys, containing 440 and 900 ppm Mn, have been measured as a function of temperatureT from their transition temperaturesT _c down toT=0.07 K. The observedT _c depression can be understood in terms of Kaiser's theory for nonmagnetic localized states in superconducting alloys, with an effective Coulomb coupling constantN _d (0)U _eff equal to 0.43 for the AlMn alloys. Additional evidence that the Mn impurities do not possess a well defined magnetic moment in aluminum in this temperature range is obtained from the critical field results. In particular, the BCS law of corresponding states is obeyed by these alloys. We conclude that these AlMn alloys can be considered BCS superconductors, with a pairing interaction which is weaker than that in pure aluminum.Research supported by the National Science Foundation.     

碳酸钙对磷渣-煤矸石烧结多孔微晶玻璃结构和性能的影响

多孔微晶玻璃具有导热系数低、力学性能好、抗腐蚀性强等优点,是一种隔热、吸声的轻质功能材料.为拓展多孔微晶玻璃的制备原料范围,同时大宗量、高附加值利用工业废渣-磷渣和煤矸石.本文以磷渣和煤矸石为原料,采用烧结法制备多孔微晶玻璃.利用X射线衍射、扫描电子显微镜及阿基米德法,对制备的试样进行表征,研究发泡剂碳酸钙掺量对体系析...     

Effect of granulometry on cementitious properties of ladle furnace slag

Ladle furnace slag (LFS), a by-product of the steel making process, was tested for its potential use as a supplementary cementing material. The material used for the tests was screened or ground, producing three samples of different fineness, and the granulometry of these LFS samples was also tested by particle size analysis. Their chemical and mineralogical composition was assessed by chemical analysis, X-ray diffraction and thermogravimetric analysis. Finally, in order to determine the cementitious and pozzolanic character of LFS in relation to its granulometry, slag-lime and slag-cement mortars were produced and tested in compression. The results show that although LFS is a weak supplementary cementing material, it shows some self-cementing and pozzolanic properties that can be enhanced by screening or grinding the raw material. Even though different levels of fineness and granulometry can be reached with each method, generally, grinding seems to improve LFS binding properties more than sieving.     

镍渣机械力化学效应及其对反应活性的影响

为提高镍渣的反应活性,根据机械力化学原理,采用高能球磨技术处理镍渣并采取蒸压工艺制备镍渣制品.通过粒径分析、X射线分析以及扫描电镜分析等手段研究不同高能球磨时间下镍渣的粒径、结构和形貌变化以及镍渣的反应活性变化.结果表明:高能球磨可以进一步细化镍渣,使大颗粒块状粉体破裂、表面粗糙化并提高镍渣的反应活性,长时间球磨可使水化样品诱导期和加速期两个阶段的水化放热量显著增大;高能球磨4 h时镍渣蒸压试块的强度最大,可达24.4 MPa,是未高能球磨时的4.5倍,球磨4 h后蒸压试块水化产物的X射线谱图中出现了硬硅钙石、托勃莫来石和镁水化物等衍射峰.     

Effect of manganese on the oxidation of Fe-Mn-Al-C alloys

The effects of manganese on the oxidation of alloys with the chemical composition (wt%) Fe-5AAl-1.5Mn-0.58C and Fe-5.3Al-3.5Mn-0.53C at 600, 800 and 1000° C in dry air were investigated. Kinetic curves were determined by thermogravimetric analyses. Optical metallography and electron probe microanalysis were used to examine the oxide scales. The kinetic curves of Fe-5.4Al-1.5Mn-0.58C alloy oxidized at 600, 800 and 1000° C had simple, three- and two-stage parabolic rate laws, respectively. On the other hand, two stages of linear rate law were observed in Fe-53Al-3ZMn-0.53C alloy when oxidized at 600° C, while two distinct parabolic rate laws were found in the same alloy oxidized at 800 and 1000° C. Oxidation behaviours and the oxide formation mechanisms of the alloys at different temperatures are discussed in this paper.     

橘皮色素的微波辅助提取及其抗氧化活性研究

以象山一家罐头厂所废弃的橘子皮为原料,研究了橘皮中功能色素的不同提取工艺.在单因素水提试验的基础上,用微波辅助水提法进行正交试验,得到了橘皮色素的最佳浸提条件为:微波处理2 min,料液比为1∶12,70℃下浸提1次,每次3.5 h,在此条件下提取物多酚含量可达0.037 mg/mL;通过DPPH法测定橘皮提取物的抗氧化性能.结果表明,随着提取物质量浓度的增加而增大.