KR法铁水脱硫工艺的探讨

介绍了KR法铁水脱硫工艺的发展、脱硫的原理、该工艺的优、缺点及影响脱硫效果的因素,对喷吹和KR脱硫工艺进行了比较,为铁水脱硫装置的选择提供借鉴.     

Densities of molten nickel mattes

The densities of molten nickel mattes Cu₂S-Ni₃S₂ and FeS-Ni₃S₂ were measured in the temperature interval 970° to 1321°C over the complete composition range. Several density values were also obtained for the ternary matte Cu₂S-FeS-Ni₃S₂ in the same temperature range. The densities of the binary mattes Cu₂S-Ni₃S₂, FeS-Ni₃S₂ and ternary matte Cu₂S-FeS-Ni₃S₂ were measured as 4.94 to 5.83 g per cu cm, 3.55 to 6.23 g per cu cm, and 2.65 to 4.92 g per cu cm, respectively. Molar volumes and excess molar volumes of the binary mattes were evaluated.     

Deoxidation equilibria of molten nickel by Mg-Al and Mn-Al

The deoxidation equilibria of aluminum-magnesium and aluminum-manganese in liquid nickel equilibrated with Al₂O₃-saturated MgAl₂O₄ and MnAl₂O₄, respectively, were investigated in the temperature range of 1773 to 1873 K. At 1773 K, the oxygen levels could be reduced to 5.8 to 6.6 ppm with 2.5 to 10 ppm magnesium and 0.05 to 0.9 mass pct aluminum in the Ni-Mg-Al-O system, and to less than 20 ppm with more than 1.5 mass pct manganese and 30 ppm aluminum in the Ni-Mn-Al-O system. With the experimental results mainly obtained in the present work, the interaction parameters, e _Mg ^Al , e _Mn ^Al , e _O ^Mg , e _O ^Mn , and e _O ^Al , and the equilibrium constants, log , log , log K _Mg(Ni), log K _Mn(Ni), and log K _Al(Ni), were estimated using a multiple regression analysis.     

Penetration of molten nickel into sintered titanium carbide hard metals

Conclusions A study was made of some aspects of molten nickel penetration into titanium carbide hard metals. It is shown that, when such a liquid phase migrates through a semiinfinite rod, the variation of the concentration of the binder metal along the length of the rod may be described by a hyperbolic function. The dependence of the thickness of the layer of increased nickel content on time of contact between the specimen and the melt was determined. It is demonstrated that, by employing the method of infiltration of a hard metal with a liquid metal, it is possible to produce parts possessing varying physicomechanical properties.Translated from Poroshkovaya Metallurgiya, No. 11(215), pp. 25–38, November, 1980.     

The thermodynamic behavior of sulfur in molten nickel and nickel-base alloys

The thermodynamic properties of dilute solutions of sulfur in pure liquid nickel were investigated at 1500, 1550, and 1575°C for sulfur concentrations up to 0.7 wt pct. Based on the infinitely dilute, wt pct standard state, the equilibrium data obtained for the reaction: H₂(g) + S = H₂S(g) were fitted by the equations: logK = − 1489/T − 1.772, and ΔG° = 6812 + 8.11T, cal/mole. For the solution ofS ₂(g) in pure Ni according to the reaction: 1/2S ₂(g) = S (in Ni), the standard free energy of solution is found to be: ΔG° = - 28,342 + 3.62T, cal/mole. For the very dilute solutions of sulfur normally encountered in nickel-base melting, the activity coefficient of sulfur in pure Ni at 1575°C is given by: log f_S= -0.035 (pct S). The effects of alloying elements normally used in nickel-base alloys on the activity coefficient of sulfur in molten nickel were investigated. The activity coefficient of sulfur is increased by all of the alloying elements studied, as evidenced by the interaction parameters: e_S ^fe = +0.005, e_S ^Cr = +0.030, e_S ^Mo = +0.053, e_S ^Ti = +0.160, and e_S ^A1 = +0.133. Measured values of the activity coefficient of sulfur in the quaternary system Ni-S-Cr-Fe agreed reasonably well with those predicted from binary and ternary data. This work constitutes a portion of the work performed by W. F. VENAL for the Ph.D. degree from the University of Illinois at Chicago Circle. Formerly Professor of Metallurgical Engineering at UICC.     

Kinetics and mechanism of the reduction of molten nickel sulfide by hydrogen

The kinetics and mechanism of the reduction of M₃S₂ by hydrogen have been investigated between 1133° and 1300°C. When high flow rates of hydrogen and argon or helium bubbling through the melt are maintained the rate-determining step is a chemical process which can be expressed by a rate law of the form $$\begin{gathered} r_{H_2 S} = k_{expt} (N_S - \alpha )^2 p_{H_2 }^{1/2} \hfill \\ p_{H_2 } \geqslant 0.88atm \hfill \\ \end{gathered} $$ where k_expt = 85.1 atm^-1/2 min^-1, α = 0.17 at 1250°C. The experimental activation energy for this process is 20.1 ±3.0 kcal per mole. These results are discussed in terms of possible catalysis by nickel.     

Thermal conductivities of molten iron, cobalt, and nickel by laser flash method

New attempts were made for the measurement of thermal diffusivity of molten iron, cobalt, and nickel at temperatures close to 1900 K by a laser flash method. A simple but useful sample cell system was developed to keep the molten metal shape uniform for a given thickness. It is also necessary to consider the effect of not only the radiative heat loss but also the conductive heat loss at the interface between the molten metal sample and the sample cell material under the present experimental conditions. The conductive heat loss was found, through computational simulation, to be negligibly small for the present laser flash measurements. Thermal conductivity values of molten iron, cobalt, and nickel were calculated by combining the present thermal diffusivity data with specific heat and density, and the resulting values are given in the following equations (unit: W m⁻¹ K⁻¹)

活性炭脱硫技术在烧结烟气脱硫中的应用

介绍了活性炭脱硫技术在烧结烟气脱硫中的应用,分析了活性炭脱硫技术的机理和特点,同时阐述了活性炭脱硫技术的现状以及未来的发展趋势。     

影响CaO基复合脱硫剂脱硫效率的因素分析

从脱硫原理上分析脱硫的影响因素,分析了石灰质量、粉剂粒度、铁水装入量、铁水温度及铁水中钛含量等对脱硫的影响.在国内某钢厂使用业绩表明:脱硫粉剂中ω(CaO)达到90％、粉剂粒度小于0.15 mm比例占96％时,脱硫效率达95.1％,粉剂消耗从17 kg/t降低至13.5 kg/t.     

The sulphation of nickel and cobalt ferrites and sulphides by molten sodium pyrosulphate and sodium bisulphate

Abstract

Synthetic ferrites and sulphides of nick-el and cobalt were sulphated in the presence of molten sodium pyrosulphate and sodium bisulphate. The ferrites may be sulphated readily; hence it is unlikely that they would retain unreacted nickel or cobalt during the sulphation of the corresponding oxides.

In the presence of either sodium pyrosulphate or sodium bisulphate, nickel and cobalt sulphides may be sulphated directly, but at higher temperatures the oxide forms as an intermediate compound.

Résumé

Des ferrites et des sulfures synthétiques de nickel et de cobalt ont été sulfatés en présence de pyrosulfate et de bisulfate de sodium fondus. Les ferrites peuvent être facilement sulfatés, dès lors il parait improbable qu'ils accaparent du nickel ou du cobalt durant la sulfatation des oxydes correspondants.

En présence, soit de pyrosulfate de sodium soit de bisulfate, les sulfures de nickel et de cobalt peuvent être sulfatés directement, mais à températures élevées, il y a formation d'oxyde en tant que composé intermédiaire.     

镁粒脱硫工业试验研究

通过采用冷态模拟试验,确定了合适的喷吹工艺参数,设计了喷吹镁粒设备在酒钢炼钢厂脱硫站进行了工业试验.试验结果表明:采用喷吹镁粒脱硫工艺,其脱硫率在85%～92%之间,铁水温降10～15℃,镁粒耗量吨铁0.45～0.60 kg.镁粒脱硫工艺与其它脱硫工艺相比,具有脱硫效率高、铁水温降小、产生的渣量少、对环境的污染少等特点.     

60 t LF脱硫试验

为充分发挥酒钢LF的精炼功能,选择含Ba0的复合渣系,在酒钢60t LF上进行了脱硫试验。结果表明,试验渣的脱硫效果理想,最高达到71．3％,平均脱硫率达到59．8％。说明酒钢LF已具备发挥其精炼功能的条件。切实改进工艺制度,加强操作,使LF脱硫功能得以实现。     

武钢KR脱硫工艺改进

介绍了武钢炼钢总厂二分厂KR脱硫工艺的改进。通过优化了脱硫剂的成分,使脱硫效果得到明显改善,脱硫剂单耗大幅降低;优化了搅拌、扒渣工艺并采取底吹技术,大幅减少了扒渣过程中的金属损失;改进了搅拌器形状和制作工艺,提高了搅拌器寿命,并减少了修补料消耗;开发了脱硫自动控制模型,提高了生产效率,改善了操作环境。     

KR脱硫自动控制系统的应用

武钢炼钢总厂二分厂为了进一步提高品种钢冶炼能力,对KR脱硫过程全智能化控制技术进行了研究。开发了脱硫动态在线控制模型,并用BP神经网络控制系统优化参数,实现了全自动智能化一键式脱硫。生产实践表明:一键脱硫比达到99%,一次脱硫命中率达到99.5%,脱硫效果稳定,脱硫剂利用率提高,最大限度地降低了脱硫成本。     

HPF煤气脱硫工艺在韶钢焦化厂的应用

介绍了H．P．F法煤气脱硫工艺在焦炉煤气净化系统的应用,对生产中影响煤气脱硫效率的因素进行了分析和改进,提高了煤气脱硫效率．