共查询到20条相似文献,搜索用时 68 毫秒
1.
2.
3.
4.
由于产生“折痕”进行分级的表面缺陷镀锌钢带,用户再加工时,通常导致镀锌钢带断裂。对于镀锌钢带来说,这种缺陷最具代表性。在厚度大于1mm的低碳钢轧材上最容易产生这种缺陷。个别情况下,“折痕”这种缺陷在钢带生产进程中就已表现出。但是,大多数情况下,只有在用户对钢材进行加工时(开卷时,钢带切割时,成型等),这种缺陷的存在较为明显。 相似文献
5.
6.
7.
结合河钢唐钢CQ级镀锌钢带生产实际,详细分析了其弯曲加工横折纹、拉矫纹、拉矫亮印的产生原因,认为拉矫机延伸率使用不当是导致带钢缺陷的根本原因,并通过调试试验进一步表明了延伸率与弯曲加工性能及拉矫纹之间的关系。结果表明,带钢厚度相同时,延伸率越大,屈服平台越短;延伸率相同时,带钢越厚,屈服平台越短;随延伸率增加,屈服平台相应缩短,弯曲加工性能得到有效提高,但拉矫纹严重程度也有所增加。通过优化拉矫机延伸率及规范拉矫工艺制度,提高了带钢的弯曲性能,使产品质量大幅提高,异议数量大幅降低,经济效益极大提高,具有很强地推广和示范作用。 相似文献
8.
9.
10.
11.
锌渣的产生是热镀锌生产中锌损耗的一个重要途径,在生产成本中占有很大比例,通过改进工艺操作方法,降低实际生产中锌渣的生成量,对提高生产质量,降低成本,增强企业竞争力有非常重要的意义,文章介绍了降低锌锅出渣率的途径及所采取的措施。 相似文献
12.
氰化钠浓度的测定及控制是黄金生产中的重要研究课题。本文研究了用比色法测定金矿氰化液中游离氰化钠的方法,为国内研制氰化钠自动分析仪打下基础。 相似文献
13.
14.
As a refractory gold mineral, pyrite needs to be oxidised prior to gold leaching. In this study, the effect of [Cl?] concentration (40.6–149.8?g/L), [Cu2+] concentration (0.8–31.6?g/L), pH (1.5–2.5) and temperature (25–90 –C) on the pyrite leaching rate was investigated. In addition, the open circuit potential (OCP) values of pyrite in cupric chloride solution were investigated. A linear regression model was constructed to predict pyrite dissolution rate i.e. corrosion current density. It was shown that the temperature had a significant positive effect on pyrite dissolution, while increased cupric ion concentration was also shown to provide some dissolution enhancement. According to the regression analysis, pH had no effect on the corrosion current density at OCP. Dissolution rates of pyrite varied between 0.05 and 2.9?µm/h. The activation energy values varied from 20 to 90?kJ/mol, indicated that the pyrite dissolution reaction rate was controlled by the chemical reaction or mixed mechanism rather than diffusion alone. The simultaneous increase in corrosion potential and corrosion current density indicated that the anodic pyrite dissolution reaction was rate determining at OCP. 相似文献
15.
16.
S. K. Jena P. K. Misra B. Das 《Mineral Processing and Extractive Metallurgy Review》2016,37(5):323-332
The extractions of potassium value from feldspar via roasting and leaching route was studied with a focus on the effects of the roasting time, temperature, additives, and particle size. Sodium chloride and phosphogypsum (PG) were used as a source of chloride and calcium, respectively, and played the important role during the roasting of feldspar. When the feldspar sample was roasted at 900°C with sodium chloride alone, the extraction of potassium was limited to 61%. The extraction could go up to 92.5% by the addition of phosphogypsum along with sodium chloride. The optimum conditions of potassium extraction were found to be, particle size 100 µm, roasting temperature 900°C and roasting time of one hour. The X-ray diffraction study indicated the formation of sylvite (KCl) in the roasted product and its disappearance in roast-leach residue due to its high water solubility. The morphological changes during the roasting process were clearly observed by field emission scanning electron microscope (FESEM) images. The extraction of potassium from feldspar was best fitted by the Ginstling and Brounshtein kinetic model. The activation energy of 238.6 KJ/mole and 28.73 KJ/mole for low and high-temperature regions indicated that the overall extraction process follows two-steps reaction path. 相似文献
17.
研究了铂在丙醇-硫氰化钾-氯化钠-水体系中的析相萃取行为及与一些金属离子分离的条件。结果表明,丙醇的水溶液在氯化钠的作用下可分成醇/水两相,在分相过程中,Pt(Ⅳ)与硫氰化钾生成的[Pt(SCN)6]2-可与质子化的丙醇 [PrOH2]+形成离子缔合物[Pt(SCN)6]2-·2[PrOH2]+而被丙醇相完全萃取。当溶液中丙醇、硫氰化钾和氯化钠分别为30%(V/V)、6.0×102- mol/L和0.16 g/mL时,Pt(Ⅳ)的萃取率达到98.2%以上,而试液中的Mo(Ⅵ)、Ce(Ⅲ)、Ni(Ⅱ)、V(Ⅴ)、Cr(Ⅲ)、Ag(Ⅰ)、Mn(Ⅱ)、Mg(Ⅱ)、Cd(Ⅱ)、Ga(Ⅲ)、Fe(Ⅱ)和Al(Ⅲ)几乎不被萃取,从而实现了Pt(Ⅳ)与这些金属离子的分离。方法应用于Ni-Pt/Al2O3催化剂中铂的分离萃取和测定,测得结果与参考值基本一致,相对标准偏差(RSD,n=5)为2.3%。 相似文献
18.
研究了正丙醇-硫氰酸钾-水体系析相萃取分离和富集Ti的行为及与一些金属离子分离的条件。结果表明, 氯化钠能使正丙醇的水溶液分成两相,在分相过程中, Ti和硫氢化钾生成的Ti(SCN)62-与质子化正丙醇C3H7OH2+ 形成的缔合物[Ti(SCN)62-][C3H7OH2+]2能被正丙醇相完全萃取。当正丙醇、硫氰酸钾和氯化钠的浓度分别为30%(V/V)、8.0×10-2 mol/L和0.17 g/mL时, Ti的萃取率达到98.9%以上,V、Ce、Mg、Mn、Cd、Cr、Al、Fe、Zn、Ni、Ag 和 W不被萃取,实现了Ti与上述金属离子的分离。对合成水样中的钛进行分离和测定, 结果满意。 相似文献
19.
试验了在氯化钠存在下,Bi3+以BiI4-络阴离子萃取到正丙醇相的最佳条件。结果表明,氯化钠能使正丙醇的水溶液分成两相,在分相过程中,Bi3+与碘化钾生成的BiI4-与质子化正丙醇(C3H7OH2+)形成的缔合物[BiI4-][C3H7OH2+]能被正丙醇相完全萃取。当正丙醇、碘化钾和氯化钠的浓度分别为30%(V/V)、6.0×10-3mol/L、0.2 g/mL时,Bi3+的萃取率达到99.2%以上,Fe2+、Co2+、Ni2+、Ag+、Mn2+、Cr3+、Ce3+、Zn2+和Al3+基本不被萃取,实现了Bi3+与上述金属离子的分离,对合成水样和锌铋合金中Bi3+的分离和测定,结果满意。 相似文献
20.