Phosphorus Distribution Ratio between Multi Phase CaO–FeO&lt;sub&gt;t&lt;/sub&gt;–SiO&lt;sub&gt;2&lt;/sub&gt;–P&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;5&lt;/sub&gt; (6%–13%) Slags with MP Near Hot Metal Temperature and C-saturated Molten Iron at 1573 K

Shi

et al. 2021

Metals

In this paper, the influence of the Fe2O3 addition amount on the dephosphorization of hot metal at 1623 K with the slag of the low basicity (CaO/SiO2) of about 1.5 was investigated by using high-temperature laboratorial experiments. With increasing the Fe2O3 addition amount from 5 to 30 g, the contents of [C], [Si], [Mn] and [P] in the hot metal at the end of dephosphorization are decreased and the corresponding removal ratios increase. In dephosphorization slags, the phosphorus mainly exists in the form of the nCa2SiO4–Ca3(PO4)2 solid solution in the phosphorus-rich phase and the value of coefficient n decreases from 20 to 1. Furthermore, the oxygen potential and activity at the interface between the slag and hot metal are increased. When the oxygen potential and the oxygen activity at the interface are greater than 0.72 × 10−12 and 7.1 × 10−3, respectively, the dephosphorization ratio begins to increase rapidly. When the Fe2O3 addition amount is increased to 30 g, the ratio of the Fe2O3 addition amount to theoretical calculation consumption is around 175%, and the dephosphorization ratio reaches the highest value of 83.3%.

Section: Effect Of the Fe2o3 Addition Amount On The Oxygen Activity Amentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Effect of the Fe2O3 Addition Amount on Dephosphorization of Hot Metal with Low Basicity Slag by High-Temperature Laboratorial Experiments

Shi

et al. 2021

Metals

“…In addition, the mineral structure and the composition of phosphorus‐rich phase in dephosphorization slag at low temperature and low basicity have been studied. [ 17–33 ] It was reported that the phosphorus is mainly enriched with the form of n Ca 2 SiO 4 ‐Ca 3 (PO 4 ) 2 (hereafter denoted as n C 2 S‐C 3 P) in the phosphorus‐rich phase whether the dephosphorization slag is cooled in the atmosphere of air or argon. [ 17 ] The crystal phase obtained in dephosphorization stage is stabler than that in desiliconization stage.…”

Section: Introductionmentioning

confidence: 99%

Effect of Temperature on Dephosphorization of Hot Metal in Double‐Slag Converter Steelmaking Process by High‐Temperature Laboratorial Experiments

Shi

et al. 2020

steel research int.

The influence of temperature on the dephosphorization of hot metal at the low temperature range of 1300–1450 °C with the slag of the low basicity (CaO/SiO2) of about 1.8 is investigated using high‐temperature laboratorial experiments. The results show that with increasing temperature, the phosphorus contents in hot metal decrease first and then increase. The phosphorus can be removed from the initial content of 0.246% to the final content of 0.066% with the highest dephosphorization ratio of 73.2% at 1375 °C. The P2O5 content in slag increases first and then decreases. When the actual dephosphorization temperature is 1350–1375 °C being about 60 °C higher than the conversion temperature of decarbonization and dephosphorization, a very high LP of about 25 can be obtained. Moreover, the dephosphorization slag at the temperature from 1300 to 1400 °C is mainly comprised of three mineralogical phases: phosphorus‐rich, metal oxide (RO), and CaO–FeO–SiO2 phases. When the temperature is increased to 1425 and 1450 °C, the dephosphorization slag is mainly comprised of liquid slag containing Ca3(PO4)2 and RO phase.

Effect of the Initial P Content on Dephosphorization of Hot Metal with Low Basicity Slag at 1623 K

Zhang

et al. 2021

steel research int.

The effect of the initial P content ranging from 0.057% to 0.292% in hot metal on dephosphorization with low basicity (CaO/SiO2) slag at 1623 K is investigated using high‐temperature laboratorial experiments. With increasing initial P content in the hot metal, the dephosphorization ratio increases first and then decreases, with the highest dephosphorization ratio of 83.2% at the initial P content in the hot metal of 0.173%. The phases in dephosphorization slags are basically consistent, which are mainly composed of nCa2SiO4‐Ca3(PO4)2, Ca2SiO4, metal oxide, Ca3(PO4)2, Ca3Mg(SiO4)2, Ca2Fe2O5, and MgAl2O4. The compositions of all the P‐rich phases are close to the connection line between Ca2SiO4 and Ca3(PO4)2 in the phase diagram. In addition, with increasing the initial P content in hot metal, the viscosity and activation energy values of the dephosphorization slag increases at the present dephosphorization temperature of 1623 K and the values of the activation energy of the dephosphorization slags increase gradually. The area fractions of Q0 + Q1 (Qi, i is the number of bridging oxygen per silicon atom) units decrease, whereas those of the Q2 + Q3 units increase. The average number of nonbridging oxygen per silicon atom (NBO/Si) value decreases, indicating that the degree of the polymerization (DOP) of the corresponding dephosphorization slag increases resulting in the increased viscosity.