高频红外碳硫分析仪CS-8800检测铸铁中碳硫元素含量的方法研究

碳是铸铁材料中的重要组分,含碳量的多少对铸铁材料的性能有重要的作用,在一定范围内铸铁的硬度强度会随着含碳量的增加而增加,碳含量的测定在铸铁成分分析中是一个重要的项目,它对评价铸铁材料的质量、性能、材质等方面是不可缺少的判定依据;硫在铸铁材料中是一种有害元素,它主要以硫化铁、硫化锰形式存在,能够引起材料的热脆、降低材料的力学性能,因此硫的测定也就成为了铸铁分析中一项常规检测项目,硫含量的检测结果是材料质量和性能判别的重要重要依据,因此碳硫含量的多少是确定铸铁产品质量的重要元素,我们通过反复的实验得出最适合的分析条件,从而获得满意的碳硫含量检测结果。     

库仑滴定法测定铁矿石中的硫

采用库仑滴定法铁矿石中的硫含量,利用智能测硫仪,在催化剂作用下,使铁矿中的硫在高温下以ＳＯ２形式释放出来,用电解生成的磷滴定Ｈ２ＳＯ３,该方法准确度好,测量范围宽。     

人体必需矿物质与营养强化剂

必需矿物质是维持人体正常生理功能所必需的,但我国居民普遍缺乏铁、钙等必需矿物质。食品营养强化是纠正营养缺乏和改善居民健康的重要手段,但我国居民对矿物质营养强化剂的认识仍有很多误区。从人体必需矿物质的生理功能出发,介绍了目前我国常用的矿物质营养强化剂和载体,指出了食用矿物质强化食品的注意事项。     

Iron-sulfur cluster biogenesis systems and their crosstalk

The biogenesis of iron-sulfur clusters ([Fe-S]) plays a very important role in many essential functions of life. Several [Fe-S] biogenesis systems have been discovered, such as the NIF (nitrogen fixation), SUF (mobilisation of sulfur) and ISC (iron-sulfur cluster) systems in bacteria, and the ISC-like and CIA (cytosolic iron-sulfur protein assembly) systems in yeast. Experimental evidence has revealed that SUF and ISC in bacteria communicate with each other partly through IscR to coordinate the utilisation of iron and cysteine. The ISC-like system in yeast is localised to the mitochondria, while the ISC-dependent CIA system is localised to the cytosol; this suggests a possible role for the ISC mitochondrial export machinery in mediating crosstalk between the two systems. Based on genetic analysis, the model plant Arabidopsis thaliana contains three [Fe-S] biogenesis systems similar to SUF, ISC and CIA named AtSUF, AtISC and AtCIA. Possible communication between these three systems has been proposed.     

和田河OR-GREEN硫磺回收装置运行分析

采用OR-GREEN硫磺回收技术处理和田河天然气处理站MDEA装置富集的酸性尾气,在常压、低温的条件下将酸性气中的H2S直接转化为单质硫磺,反应后外排尾气中H2S含量小于10 mg/kg。介绍了OR-GREEN硫磺回收装置的基本结构,对系统热量平衡进行分析,并对投产运行情况作了简单总结。     

硫磺制酸装置大型化的探讨

介绍了我国硫磺制酸的现状及发展历程,并对我国典型的大型化的硫磺制酸装置进行了简述,同时,对硫磺制酸的技术发展、热能回收利用情况、大型化装置的质量管理办法等进行了分析。     

Understanding the effects of sulfur on mercury capture from coal-fired utility flue gases

Coal combustion continues to be a major source of energy throughout the world and is the leading contributor to anthropogenic mercury emissions. Effective control of these emissions requires a good understanding of how other flue gas constituents such as sulfur dioxide (SO₂) and sulfur trioxide (SO₃) may interfere in the removal process. Most of the current literature suggests that SO₂ hinders elemental mercury (Hg⁰) oxidation by scavenging oxidizing species such as chlorine (Cl₂) and reduces the overall efficiency of mercury capture, while there is evidence to suggest that SO₂ with oxygen (O₂) enhances Hg⁰ oxidation by promoting Cl₂ formation below 100 °C. However, studies in which SO₂ was shown to have a positive correlation with Hg⁰ oxidation in full-scale utilities indicate that these interactions may be heavily dependent on operating conditions, particularly chlorine content of the coal and temperature. While bench-scale studies explicitly targeting SO₃ are scarce, the general consensus among full-scale coal-fired utilities is that its presence in flue gas has a strong negative correlation with mercury capture efficiency. The exact reason behind this observed correlation is not completely clear, however. While SO₃ is an inevitable product of SO₂ oxidation by O₂, a reaction that hinders Hg⁰ oxidation, it readily reacts with water vapor, forms sulfuric acid (H₂SO₄) at the surface of carbon, and physically blocks active sites of carbon. On the other hand, H₂SO₄ on carbon surfaces may increase mercury capacity either through the creation of oxidation sites on the carbon surface or through a direct reaction of mercury with the acid. However, neither of these beneficial impacts is expected to be of practical significance for an activated carbon injection system in a real coal-fired utility flue gas.     

蒸汽回转干燥机在高硫铁精矿干燥中的应用

介绍了某冶炼厂高硫铁精矿蒸汽回转干燥机的工艺流程、设备特性和生产实践,分析了试车生产过程中出现的问题,并提出了有效的解决方案。     

硫磺胶粘接铸铁引起的电化学腐蚀

分析了硫磺胶在露天粘接铸铁引起的电化学腐蚀,提出了在金属粘接中应用平衡电位和罩面密封以防止电化学腐蚀.     

络合铁法脱硫的利与弊

介绍采用络合铁脱硫出现的悬浮硫上升、溶液混浊等问题,从反应机理分析出现这些现象的原因,采取加入酞氰类脱硫剂的方法解决,效果良好。     

沼铁矿条状脱硫剂研究

论述了氧经以剂硫原理及影响因素,并通过成型脱硫和再生试验,以沼铁矿为原料研制出性能优良,价格便宜的条状脱硫剂,该脱硫剂的一次硫容为１０％,累计硫容达４０％以上。     

类球形低硫磷酸铁的制备技术研究

磷酸铁(FePO4)是锂电池正极材料磷酸铁锂(LiFePO4)的核心前驱体,FePO4形貌及硫含量对合成的LiFePO4材料性能有重要影响。为得到类球形低硫FePO4产品,在传统液相沉淀法技术基础上做了改进优化,添加十六烷基三甲基溴化铵(CTAB)作为形貌助剂提高产品球形度,添加氨水作为配体形成磷酸铁铵配合物改善结晶过程,降低产品硫含量。结果表明:所制备的FePO4产品硫质量分数低,达到2.6×10^-5,形貌为均一的微米类球形颗粒,D50=11.4μm,振实密度达到1.22 g/cm^3,有望成为制备高压实密度LiFePO4材料的核心前驱体。     

黄铁矿脱硫菌生长和代谢的影响因素研究

研究了氧化亚铁硫杆菌（简称T．f．菌）对几种氮源、能源的利用，以及空气中氧化不同时间的黄铁矿吸附菌的代谢活性。结果表明：在选择的3种氮源中，尿素经过诱导可被T．f．菌较好地利用，说明该菌可产生诱导性脲酶。在选择的能源中，Fe^2＋是T．f．菌容易利用的能源基质。添加接种培养过的残留单质硫粉可提高菌体氧化单质硫的速率。在空气中氧化20d的黄铁矿对T．f．菌的吸附量增大，而且吸附菌体的亚铁氧化过程提前进行。     

中原油田采油四厂南二线腐蚀因素研究

中原油田腐蚀之严重是其它油田无法比的,尤其是采油四厂南二线。最近,我们专门对此做了部分分析和研究,基本探明其原因,并做了相应的分析,提出了相应的对策以供参考。     

高频红外碳硫分析仪测定铁矿物硫含量

通常采用燃烧--中和法或燃烧-碘量法测定铁矿物中硫含量,这些测定方法耗时长,矿样熔融不完全,导致测定结果不稳定.尝试采用HCS-216A高频红外碳硫仪测定,在试验条件下,该法测定硫含量为1.18%、1.84%的标样,测定值为1.181%、1.844%,相对标准偏差(RSD)小于0.35%(n=9).采用本法与常规燃烧中...     

Sulfur/sodium bentonite prills as sulfur fertilizers. 2. Effect of sulfur-sodium bentonite ratios on the availability of sulfur to pasture plants in the field

Sulfur/sodium bentonite prills containing 5–40% of sodium bentonite were evaluated in a field experiment to determine the effects of the bentonite contents on their ability to supply sulfur to pasture plants. Comparative rates of oxidation of the elemental sulfur in the fertilizers to sulfate were deduced from plant sulfate contents and phosphate-extractable sulfate in soil (0–75 mm depth) over a period of 15 months. In grass-dominant pastures plant sulfate appeared to be more sensitive than soil sulfate to differences between S fertilizers.Increasing the proportion of bentonite in the prills from 5% to 40% increased the rate at which sulfur became available for plant uptake. At least 10% bentonite content was necessary to allow a satisfactory rate of supply to plants in the first year after application. Plant sulfate concentrations were increased by the S°/bentonite treatments for the whole of the experimental period of 467 days. In contrast gypsum only increased plant sulfate levels for about 118 days. Prills containing 40% bentonite also maintained sulfate concentrations longer than did finely divided elemental S. However oxidation of S from S°/bentonite prills lagged behind elemental S powder of similar fineness due to the delay for prill disintegration and less uniform distribution of S.In a cool-temperate climate with sufficient rainfall for significant leaching of sulfate, the optimum bentonite content of S°/sodium bentonite prills as fertilizer for pasture was about 15%. 20% sodium bentonite may be more appropriate in dry cool-temperate environments, whereas in warm moist temperate environments prills containing 10% sodium bentonite may be satisfactory.     

我国三氧化硫磺化生产装置的最新发展

简要介绍了国内正在运转的三氧化硫磺化装置的发展状况。分别就生产规模、生产装置的集中化发展及其地区分布情况进行了分析。     

硫磺制酸大型装置国产化实践

近10年间，我国硫磺制酸大型装置装备技术得到了飞快发展，但其中的个别关键设备和钒催化剂以引进的居多。介绍了完全国产化的280kt／a硫磺制酸装置的焚硫、转化、干吸、余热发电各工序的工艺技术、主要设备及生产运行情况，建议在干吸系统低温热回收技术等方面要抓紧攻关。