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1.
曹勤  周沁 《环境保护》1991,(1):21-21
铝在自然界广泛分布,由于天然存在(?)人类活动的污染,使铝存在于空气、食物和水中。近年来,文献报导用于肾透析装置的水含铝,引起病人神经紊乱;早老性痴呆症与体内铝含量增加有关,引起人们对水处理中使用铝比合物产生了怀疑。对此,笔者略谈浅见。一、天然水和处理水中的铝水环境中的铝主要来自工业废物、腐蚀、矿物及土壤沥滤、大气尘埃和底泥污染。天然酸性水含铝较高,铝加工厂附近的水可达10毫克/升以上。Miller调查美国186个水厂的水源水含铝量:地下水0.014~0.290毫克/升,地  相似文献   

2.
对聚合铝溶液中总铝的测定方法提出改进,并利用t检验比较了改进方法和国家标准方法的测定结果。结果表明.准确控制EDTA的浓度和体积,可以省略杂质金属离子的掩蔽、解蔽和反滴的过程,改进方法和国家标准方法的结果无显著性差异。  相似文献   

3.
熔炼是铝合金生产过程中的重要环节。分析了铝熔炼过程中各个阶段的特点,对反射式熔铝炉各部位要求进行阐述;在反射式熔炼炉的基础上,介绍了目前再生铝行业较先进的熔炼设备——双室炉,同时提出了铝熔炼设备的发展方向。  相似文献   

4.
河南省商电铝业所属丰源铝电公司围绕铝灰再利用做文章。由该公司研制开发的铝灰阳极碳块保护环新工艺,不仅为铝灰再利用找到了出路,进一步提高资源综合利用率,而且对减少环境污染具有重要意义。铝灰是电解铝生产过程中产生的废弃物,过去回收铝后往往被当做废品处理,既污染了环境,又造成了浪费。从2 0 0 3年3月份开始,为了解决铝灰污染问题,把回收过铝的铝灰利用独创的工艺制作成铝灰阳极碳块保护环,代替碳素保护环,起到降低碳耗和保护钢爪的作用丰源铝电公司废铝灰做出新文章@江春宵  相似文献   

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混凝过程中铝与聚合铝水解形态的动力学转化及其稳定性   总被引:17,自引:3,他引:17  
采用Ferron逐时络合比色法,并结合电泳测定研究了混凝过程中氯化铝和聚合氯化铝的水解形态动力学转化及稳定性。结果表明,AC在混凝过程中所形成的水解形态完全不同于PAC的预制水解聚合形态,其电荷及分子量均明显低于聚合铝且不稳定,AC随混凝条件如投加浓度、PH和混合时间而变,而PAC-25水解聚合形态不随混凝条件变化,始终保持稳定状态,AC水解沉淀规律与理论计算相符并形成无定形Al(OH)3絮体颗粒  相似文献   

8.
利用凝胶层析分离测定胶体态铝和溶解态铝的研究   总被引:3,自引:0,他引:3  
利用凝胶层析柱分别对高浓度(5.4g·L-1)和低浓度(0.27mg·L-1)的聚合氯化铝溶液和氯化铝溶液进行了层析分离,测定了洗脱流出液的电导率和pH值,并采用Al-Ferron逐时络合比色分析了洗脱流出液中的铝形态分布.结果表明,高浓度和低浓度铝水样中的胶体态铝和溶解态铝浓度均可采用凝胶层析法进行分离测定.利用凝胶层析装置对2.5mL铝水样以1mL·min-1的速度进行洗脱,40~60mL间的洗脱流出液即为胶体态铝,剩余部分为溶解态铝.  相似文献   

9.
天然水体中铝浓度的预测方法探讨   总被引:3,自引:0,他引:3  
本文概括了天然水体中铝的形态分类和地球化学行为,综述了天然水体中Al^3+和有机铝的浓度的预测方法,提出了由矿物浓度积,无机铝和有机铝经验关系式,有机铝模型辅以配体浓度和热力学常数预测天然水体中各形态铝的浓度的方法。  相似文献   

10.
铝盐混凝剂的研究及应用进展   总被引:4,自引:0,他引:4  
铝盐混凝剂是应用最为广泛的无机盐类混凝剂,对几种铝盐混凝剂进行了评述,复合高分子铝盐混凝剂是一类高效水处理剂,是我国铝盐混凝剂的研制方向。  相似文献   

11.
The inventory of aluminum in the atmospheric air from human activities was discussed using data from the Japanese National Air Surveillance Network. The source of atmospheric Al is considered to be mainly soil-derived particles. However, an hropogenically generated Al could also be added to airborne particulates less than 10 μm in aerodynamic diameter. Scandium, which is also found in soil dust, has a value lower than unity in enrichment factor normalized by Al. The intercept, A of the AlSc regression curve, (Al) = A + B(Sc), was much larger in industrial cities such as Kawasaki, Amagasaki, etc. This could be explained by the difference of elemental composition of various emission sources and the existence of excess Al added to airborne particulate samples.  相似文献   

12.
Al与F的络合作用对土壤吸附Al和F的影响   总被引:12,自引:0,他引:12       下载免费PDF全文
研究了Al-F络合作用对土壤吸附Al和F的影响以及吸附前的溶液中铝化学形态的差异。提高Al或F的加入量将人别使分配在土壤溶液中的F或Al的数量增加,即Al-F络合作用地使Al和F在土壤固-液间的分配平衡向液相移动,土壤对Al-F络合物吸附程度很小,吸附前,3种不同F/Al比溶液中Al^3 ,AlF^2 的浓度随着F/Al比的增加逐渐降低,AlF2^ ,AlF3^0的浓度则逐渐升高,与土壤作用后,溶液中Al主要与AlF^2 ,AlF2^ 的形式存在,以AlF^2 的数量居多。  相似文献   

13.
Finished drinking water usually contains some residual aluminum.The deposition of residual aluminum in distribution systems and potential release back to the drinking water could significantly influence the water quality at consumer taps.A preliminary analysis of aluminum content in cast iron pipe corrosion scales and loose deposits demonstrated that aluminum deposition on distribution pipe surfaces could be excessive for water treated by aluminum coagulants including polyaluminum chloride(PACl).In this work,the deposition features of different aluminum species in PACl were investigated by simulated coil-pipe test,batch reactor test and quartz crystal microbalance with dissipation monitoring.The deposition amount of non-polymeric aluminum species was the least,and its deposition layer was soft and hydrated,which indicated the possible formation of amorphous Al(OH)3.Al13 had the highest deposition tendency,and the deposition layer was rigid and much less hydrated,which indicated that the deposited aluminum might possess regular structure and self-aggregation of Al13could be the main deposition mechanism.While for Al30,its deposition was relatively slower and deposited aluminum amount was relatively less compared with Al13.However,the total deposited mass of Al30 was much higher than that of Al13,which was attributed to the deposition of particulate aluminum matters with much higher hydration state.Compared with stationary condition,stirring could significantly enhance the deposition process,while the effect of pH on deposition was relatively weak in the near neutral range of 6.7 to 8.7.  相似文献   

14.
Al的海洋生物地球化学研究   总被引:4,自引:0,他引:4  
比较系统地介绍了国内外Al的海洋生物地球化学研究进展,内容包括Al在海洋中的来源及输送通量,不同海区的分布特点,水体中的溶解态Al的赋存形式及其迁移转化规律等,简要介绍了我国在这一研究领域所取得的成果及存在的不足,并对今后的发展方向进行展望。  相似文献   

15.
Orthogonal machining of single-crystal and coarse-grained (i.e., grain size considerably larger than the uncut chip thickness) materials has been a subject to many studies in the literature. The first part of this paper presents background on machining single-crystal materials, including experimental and modeling attempts. The second part briefly describes more recent modeling results from the authors, and presents new experimental results on planing and plunge-turning of single-crystal and coarse-grained aluminum using diamond tools. The experiments indicate that (1) cutting across grains of a coarse-grained aluminum workpiece produces distinctly varying forces and surface roughness from one grain to another, (2) plunge-turning and planing of single crystal aluminum provide equivalent force data for large rake angles, (3) forces alter between two distinct levels while cutting single crystals with small rake angles, and (4) with small rake angles, subsurface damage on single-crystal aluminum is extensive, reaching depths comparable to the uncut chip thickness.  相似文献   

16.
Aluminum salt coagulants were used prevalently in various water works.In this article,the effects of filtration on residual aluminum concentration and species distribution were researched by determining the concentration of diiferent aluminum species before and after single layer filter,double layer filter,and membrane filtration units.In the research,size exclusion chromatography(SEC)was used to separate colloidal and soluble aluminum,ion exchange chromatography(IEC)was used to separate organic and inorganic aluminum, and inductivity coupled plasma-atomic emission spectrometry(ICP-AES)was used to determine the aluminum concentration.The results showed that the rapid filtration process had the ability of removing residual aluminum from coagulant effluent water,and that double layer filtration was more effective in residual aluminum removal than single layer filtration,while nano filtration was more effective than micro filtration.It was found that when the residual aluminum concentration was below 1mg/L in sediment effluent,the residual aluminum concentration in treated water was above 0.2 mg/L.The direct rapid filtration process mainly removed the suspended aluminum.The removal of soluble and colloidal aluminum was always less than 10% and the natural small particles that adsorbed the amount of soluble or small particles aluminum on their surface were difficult to be removed in this process.Micro filtration and nano filtration were good technologies for removing aluminum;the residual aluminum concentration in the effluent was less than 0.05 mg/L.  相似文献   

17.
The main aim of the study was to determine the effect of two different refinement methods on EN AW-Al99,5 primary structure and development of the refinement mechanism. The first method consisted of inoculation with a small amount of (Ti+B) according to PN-EN 573-3 standard and the second one consisted of employing an electromagnetic field during the aluminum crystallization process. These structure refinement methods are particularly important in continuous and semi-continuous casting where products are used for plastic forming. The large columnar crystal zone results in reduction of the extrusion rate on presses; moreover, during the ingot rolling delamination of external layers may occur.  相似文献   

18.
Species analysis methods for hydrolysis polymerization of aluminum   总被引:2,自引:0,他引:2  
SpeciesanalysismethodsforhydrolysispolymerizationofaluminumFengLi,LuanZhaokun,TangHongxiaoResearchCenterforEcoEnvironmenta...  相似文献   

19.
铝合金在流动海水中的腐蚀行为   总被引:2,自引:1,他引:2  
对5种铝合金在流动海水中的腐蚀行为进行了研究。研究结果表明:在静止海水中.铝合金的耐蚀性与其自然腐蚀电位值存在一定的相关性,电位越负越耐蚀。在流动海水中,铝合金比普通碳钢和紫铜耐蚀,特别是铝镁系和铝镁锰系合金,可以与90/10铜镍合金媲关。但必须严格避免与电位较正金属偶合使用,越耐蚀的铝合金越容易遭到电偶腐蚀的危害。铝铜系和铝锌镁系合金,由于在流动海水中具有明显的剥落腐蚀敏感性,不宜用于流动海水腐蚀环境。  相似文献   

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