Effect of the Initial P Content on Dephosphorization of Hot Metal with Low Basicity Slag at 1623 K. Issue 9 (3rd May 2021)

• Record Type: Journal Article
• Authors: Yang, Wenkui; Yang, Jian; Zhang, Runhao; Sun, Han
• Is Part Of: Steel research international. Volume 92:Issue 9(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-05-03
• Subjects: dephosphorization -- initial P content -- low basicities -- low temperatures -- Raman spectra -- slag viscosities; Steel -- Periodicals; Steel -- Metallurgy -- Periodicals; 669.142
• DOI: 10.1002/srin.202100066
• Languages: English
• ISSNs: 1611-3683

Abstract

Abstract : 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 n Ca2 SiO4 ‐Ca3 (PO4 )2, Ca2 SiO4, metal oxide, Ca3 (PO4 )2, Ca3 Mg(SiO4 )2, Ca2 Fe2 O5, and MgAl2 O4 . The compositions of all the P‐rich phases are close to the connection line between Ca2 SiO4 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 Q 0 + Q 1 ( Q i, i is the number of bridging oxygen per silicon atom) units decrease, whereas those of the Q 2 + Q 3 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. Abstract : 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. The highest dephosphorization ratio is 83.2% with the initial P content of 0.173% and the dephosphorization ratio increases first and then decreases with increasing initial P content.