Laboratory study of property-modified prebaked carbon anode and application in large aluminum electrolysis cells

A kind of complex additive mainly containing Al, Mg, F, and O was prepared. The synthetical performances of the property-modified prebaked anodes containing additives were tested in laboratory. On the basis of ideal testing results obtained, a large number of industrial prebaked property-modified anodes are prepared in a large-scale aluminum company. Further more, they are all used in 160 kA prebaked anode aluminum electrolysis cells. The statistic result show that, compared with common anodes, the property-modified ones enhance current efficiency by 0.78%, reduce energy consumption by 106.1 kW·h per ton aluminum and reduce carbon consumption by 11.6 kg per ton aluminum averagely. Foundation item: Project(G1999064903) supported by Major State Basic Research Development Program of China     

Typical application of Rogowski coils in inspection of electrobath

During the aluminum electrolytic roasting process, each component of the electrobath of aluminum performs unsteadily when the electrolytic bath is in the pre-roasting stage. It is important to monitor the currents of the anodes and the cathodes of the aluminum electrobath at regular intervals. Both practice and investigation indicate that Rogowski coil can be adopted to measure heavy direct current of the anodes and the cathodes of the aluminum electrobath. The paper not only introduces the typical application of the Rogowski coil to inspect the state of aluminum electrobath in the roasting process, but also analyzes the principles of the coil sensor including its dynamic properties and some important measurement results respectively. The optimal parameters of the coil can be simulated by means of an advanced simulation tool: simulink tools based on MATLAB soft environment.Based on the gathered current data, an even-current coefficient has been introduced, and the current curve can be drawn. Since they are apphed in AL-Electrolyzing, it is possible to distinguish the anode of which the current is not evenly distributed, and to take adjusting measures over a period of time to ensure that the current is evenly distributed.     

氧化铝浓相输送技术

现代大型预焙槽铝电解生产中，氧化铝的输送是非常重要的一个环节，直接影响着电解槽的正常生产。本文着重讨论氧化铝浓相输送的形式、输送机理、输送设备和技术经济指标。     

Electric field distribution in 75 kA drained aluminum reduction cell

Current distribution in a drained aluminum reduction cell is critical due to its influence on the current efficiency, electrolysis stability, anodes and cathodes integrity. A finite element model was developed to simulate the electric field in a 75 kA drained aluminum reduction cell. The current distribution and influences of the cathode inclination angle and anode-cathode distance (ACD) were studied. The results show that relatively large horizontal current density appears in the aluminum film, and the max...     

脱水改性黑液干粉除臭的研究

本文提出了脱水改性黑液干粉的除臭方法，对各方法的除臭效果进行了实验室评定，其中以焦炭吸附法效果明显、方法简便、成本低，是较理想的除臭方法．同时，对除臭机理也进行了初步探讨．     

不同ZAO粉体对ZAOp／ZAO透明导电薄膜光电性能的影响

以乙酸锌和硝酸铝为原料,氨水为催化剂,通过改变反应温度和pH值,以及干燥工艺得到三种工艺合成的ZAO粉体,即共沉淀一超临界流体干燥法（SCFD）制备的ZAO粉、共沉淀一普通干燥法制备的ZAO粉和湿态氢氧化锌铝沉淀物粉体．通过XRD,TEM,SEM和差热分析对三种ZAO粉进行了物相、颗粒大小与团聚情况和加热过程的物理化学变化进行了分析．采用浸渍一提拉法制备了ZAOp／ZAO薄膜,对其可见光透射率、导电率和表面形貌进行了测试和分析．结果表明以湿态氢氧化锌铝方式制备的ZAOp／ZAO透明导电薄膜的可见光透射率最高,大于82％;方块电阻最低,电阻为83Ω．     

脱水改性黑液在钻井泥浆中的性能研究

本文研究了脱水改性黑液作为泥浆助剂的使用性能，试验表明：它具有显著的降粘性，降滤失性、抗硬水性及抗盐性，是一种多效性泥浆助剂。     

氧化铝粉粒度及粒度分布的工艺控制

采用一次煅烧工艺、二次煅烧工艺、脱水与转相分离工艺三种后处理方式制备了一批样品，对样品的分析表明，后处理方式对粒度及粒度分布存在较大的影响，其影响主要由含水率、煅烧制度、粉碎工序在整个工艺流程中的位置三个因素决定；且采用二次煅烧工艺和脱水转相分离工艺可以有效改善粉体的粒度分布，后者的粒度分布D25／D75达到0．57．     

脱水改性黑液磺化及磺化产品性能的研究

本文对脱水改性黑液磺化及其产品性能进行了研究．结果表明：磺化后的黑液干粉静态阻垢率在加入不同量的情况下提高了3％～15％；对磷矿浆减水率也有明显增加．     

复合乳化剂浓度对PANI／PEDOT复合阳极材料导电性及结构的影响

以原位聚合法制备了导电聚合物聚苯胺／聚3,4-乙烯二氧噻吩（PANI／PEDOT）复合阳极材料．研究了复合乳化剂浓度对PANI／PEDOT复合阳极材料的电化学性能和结构的影响．用线性扫描、交流阻抗、傅里叶变换红外光谱和x-射线衍射对所得的复合阳极材料的电化学特性、物相和结构进行了表征．结果表明,当复合乳化剂浓度为0．2mol／L时,PANI／PEDOT复合阳极材料具有较好的导电性,所得复合材料的分子链有序性较好,结构规整,结晶性好．     

强化混凝-电气浮过滤处理低浊高色地下水

超低浊度高色度地下水给水水源中色度主要由溶解性有机物产生,常规混凝-沉淀-过滤工艺难以使处理后出水色度达标,为此,提出强化混凝-电解气浮过滤工艺进行除色研究.通过混凝药剂筛选及电极比选,确定最优的处理参数.实验结果显示:强化混凝阶段,最佳药剂为聚合氯化铁(PFC),其最佳投药量为40mg/L;电解气浮过滤阶段,铝电极的处理效果优于铁电极,且在铝电极作为阳极的条件下其最佳滤速为5.5m/h,运行周期12h.其出水色度达到《生活饮用水卫生标准》(GB5749-2006)的要求.     

Effect of electrolysis superheat degree on anticorrosion performance of 5 Cu/（10NiO-NiFe2O4） cermet inert anode

5Cu/(10NiO-NiFe2O4) cermet inert anodes were prepared by cold-pressing and sintering process, and the effect of superheat degree of melting K3AlF6-Na3AlF6-AlF3 on their anticorrosion performance was studied under electrolysis conditions. The results show that, the fluctuation of cell becomes small with increasing of superheat degree, which is helpful to inhibit the formation of cathodic encrustation; the concentration of impurities from inert anode in bath goes up to certain degree, but it is far smaller than those in traditional high-temperature bath. Increasing the superheat degree of melting K3AlF6-Na3AlF6-AlF3 has unconspicuous effect on the contents of impurities in cathodic aluminum. The total mass fractions of Fe, Ni and Cu in aluminum are 15.38% and 15.09% respectively under superheat degree of 95 and 195 ℃. From micro-topography of anode used view, increasing the superheat degree can aggravate corrosion of metal Cu in inert anode, and has negative influence on electrical conductivity of electrode to some extent.     

Organic Light Emitting Diodes with p-Si Anodes and Semitransparent Ce/Au Cathodes

The Ce (x nm)/Au (15 nm) stacked layers were used as semitransparent cathodes in the top-emission organic light emitting devices (TOLEDs) fabricated on a p-type silicon anodes and substrate,where x varies from 4 to 16.The consequence of the Ce layer thickness on transmittance and the device performance were studied when the organic layers NPB (60 nm)/ALQ (60 nm) were kept unchanged,where NPB was N,N'-bis-(1-naphthl)-diphenyl-1,1'-biphenyl-4,4'-diamine,and AlQ is tris-(8-hydroxyquinoline) aluminum.The cathod...     

氧化物夹杂对Al-Zn-In-Si牺牲阳极电化学性能的影响

以不同铁含量的Al-Zn-In-Si牺牲阳极为研究对象,考察了精炼前后阳极微观组织的变化.采用恒电流测试、动电位极化曲线、电化学阻抗等测试手段,对阳极的电化学性能进行了研究.结果表明：氧化物夹杂的存在使阳极的开路电位和工作电位正移,阳极的极化程度增大,同时还造成了阳极电流效率在一定程度上的损失.     

Influence of deposition voltage on phase, microstructure and antioxidation property of cristobalite aluminum phosphate coatings

Cristobalite aluminum phosphate (C-AlPO4) coatings were prepared by a hydrothermal electrophoretic deposition process on SiC-coated C/C composites. Phase compositions and microstructures of the as-prepared coatings were characterized by XRD and SEM analyses. The influence of deposition voltage on the phase, microstructure and antioxidation property of the cristobalite aluminum phosphate coatings was investigated. Results show that the as-prepared coatings are composed of cristobalite aluminum phosphate crystallites. The thickness and density of cristobalite aluminum phosphate coatings are improved with the increase of deposition voltage. The deposition amount and bonding strength of the cristobalite aluminum phosphate coatings also increase with the increase of deposition voltage. The deposition mass per unit area of the coatings and the square root of the deposition time at different hydrothermal voltages satisfy linear relationship. The antioxidation property of the coated C/C composites is improved with the increase of deposition voltage. Compared with SiC coatings prepared by pack cementation, the multilayer coatings prepared by pack cementation with a later hydrothermal electrophoretic deposition process exhibit better antioxidation property. The as-prepared multi-coatings can effectively protect C/C composites from oxidation in air at 1 773 K for 37 h with a mass loss rate of 0.53%.     

Influence of deposition voltage on phase, microstructure and antioxidation property of cristobalite aluminum phosphate coatings

Cristobalite aluminum phosphate (C-AlPO₄) coatings were prepared by a hydrothermal electrophoretic deposition process on SiC-coated C/C composites. Phase compositions and microstructures of the as-prepared coatings were characterized by XRD and SEM analyses. The influence of deposition voltage on the phase, microstructure and antioxidation property of the cristobalite aluminum phosphate coatings was investigated. Results show that the as-prepared coatings are composed of cristobalite aluminum phosphate crystallites. The thickness and density of cristobalite aluminum phosphate coatings are improved with the increase of deposition voltage. The deposition amount and bonding strength of the cristobalite aluminum phosphate coatings also increase with the increase of deposition voltage. The deposition mass per unit area of the coatings and the square root of the deposition time at different hydrothermal voltages satisfy linear relationship. The antioxidation property of the coated C/C composites is improved with the increase of deposition voltage. Compared with SiC coatings prepared by pack cementation, the multilayer coatings prepared by pack cementation with a later hydrothermal electrophoretic deposition process exhibit better antioxidation property. The as-prepared multi-coatings can effectively protect C/C composites from oxidation in air at 1 773 K for 37 h with a mass loss rate of 0.53%.     

Electrodeposition of aluminum and aluminum-magnesium alloys at room temperature

Electrodeposition of aluminum from benzene-tetrahydrofuran-Al Cl3-Li Al H4 was studied at room temperature. Galvanostatic electrolysis was used to investigate the effect of various parameters on deposit morphology and crystal size, including current density, temperature, molar ratio of benzene/tetrahydrofuran and stirring speed. The deposit microstructure was adjusted by changing the parameters, and the optimum operating conditions were determined. Dense, bright and adherent aluminum coatings were obtained over a wide range of current densities(10-25 m A/cm2), molar ratio of benzene and tetrahydrofuran(4:1 to 7:8) and stirring speeds(200-500 r/min). Smaller grain sizes and well-adhered deposits were obtained at lower temperatures. Aluminum-magnesium alloys could potentially be used as hydrogen storage materials. A novel method for Al-Mg deposition was proposed by using pure Mg anodes in the organic solvents system benzene-tetrahydrofuran-Al Cl3-Li Al H4. XRD shows that the aluminum-magnesium alloys are mainly Al3Mg2 and Al12Mg17.     

Preparation of IrO_2 MnO_2 coating anodes and their application in NaClO production

To improve the durability as well as to reduce the cost of anodes, the IrO2 MnO2 composite coating anodes for NaClO production were prepared by thermal decomposition. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction analysis (XRD) were carried out to investigate the morphologies, element distribution, and microstructure. The anodic polarization curves were employed to study the effect of sintering temperature on the Cl2 evolution reaction (CER) of the electrodes. The accelerated life tests (ALT) and electrochemical impedance spectroscopy measurement (EIS) were utilized to investigate the stability. The rules of NaClO production were also studied by the static electrolysis experiment. The results indicate that sintering temperature has a significant influence on the CER properties as well as the ALT values of the electrodes. The electrode prepared at 400°C has the best CER properties and the longest ALT value.     

稀土高纯铝箔组织、织构研究

冶炼了稀土铝中间合金,制备了不同稀土含量的高纯铝锭,通过热轧、冷轧和再结晶退火,得到铝箔.采用金相显微观察和X射线衍射分析等方法,研究了稀土元素Ce及其含量对高纯铝热轧、冷轧和再结晶退火后组织和织构的影响.结果表明,随稀土含量增加,再结晶退火后的晶粒细化,稀土的质量分数为0.005 8%时,冷轧铝箔中立方织构最多.     

铝质纤维吸声板用铝纤维的性能分析

铝质纤维吸声板用铝纤维由于制备工艺不同,形态、结构各异,影响纤维吸声板的性能。本文针对目前国内使用的3种铝纤维,研究了其形貌、表面状态对吸声板性能的影响。结果表明,采用快速凝固技术制备的铝纤维截面为圆形,表面覆有致密的氧化膜层,具有优于切削加工法制备的刨铝丝的吸声性能和耐腐蚀性能。