Physicochemical Phenomena of CO2 Injection in Polymetallic Ironmaking. Issue 7 (17th April 2021)

• Record Type: Journal Article
• Authors: Song, Hanlin; Zhang, Jinpeng; Gao, Zixian; Cheng, Gongjin; Xue, Xiangxin
• Is Part Of: Steel research international. Volume 92:Issue 7(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-04-17
• Subjects: basic oxygen furnace gas -- CO2 emission reduction -- thermodynamic feasibility -- vanadia−titania magnetite ironmaking -- waste gas recycling; Steel -- Periodicals; Steel -- Metallurgy -- Periodicals; 669.142
• DOI: 10.1002/srin.202100033
• Languages: English
• ISSNs: 1611-3683

Abstract

Abstract : Abandoned basic oxygen furnace gas (ABOFG) is a kind of byproduct fuel resource produced in the basic oxygen furnace (BOF) steelmaking process with a high temperature of 1773–1873 K and 20–40% (vol.%) CO and 20–30% (vol.%) CO2 and is usually ignited and discharged as waste gas (34.7% abandoned rate). The effects and physicochemical phenomena of injecting CO2 ‐containing ABOFG into high‐Cr‐bearing vanadia−titania magnetite ironmaking are investigated. The thermodynamic calculation shows that the ABOFG injection changes the gas partial pressure and the oxygen potential in the slag−coke interfaces and suppresses the titanium carbonitride formation. According to the results of softening−melting−dripping experiments, the content of titanium carbonitride in the high‐titanium slag decreases from 2.53% to 1.14% as the CO2 content in ABOFG increases from 0 to 30%, which is conducive to improving the high‐temperature physicochemical properties of molten slag. The recoveries of vanadium and chromium are also improved with the decrease in iron loss. Moreover, the residual coke still maintains a considerable compressive strength with a slight effect from ABOFG injection, which is expected to reduce carbon consumption. Abstract : The physicochemical phenomena of CO2 injection in polymetallic ironmaking are investigated. The recyclable CO2 ‐containing gas injection strengthens the smelting of high‐Cr‐bearing vanadia−titania magnetite, inhibits the formation of titanium carbonitride, and also is conducive to the reduction of coke consumption and carbon emission. It is feasible to reuse the abandoned basic oxygen furnace gas in a blast furnace.