Effect of V₂O₅ Addition on Oxidation Induration and Swelling Behavior of Chromium-Bearing Vanadium Titanomagnetite Pellets with Simulated Coke Oven Gas Injection into Blast Furnace

Abstract

The study discusses the oxidation induration and swelling behavior of chromium-bearing vanadium titanomagnetite pellets (CVTP) with V 2 O 5 additions, and the reduction swelling index (RSI) and compressive strength (CS) of reduced CVTP were investigated with simulated coke oven gas (COG) injection into the blast furnace (BF). The results show that the CS of CVTP decreases and the porosity of CVTP increases with increasing V 2 O 5 additions. The proportion of microsize pore size distribution of CVTP between 0 to 5 μm decreases notably while the pore size distribution between 5 to 30 μm increases with increasing V 2 O 5 additions. The V 2 O 5 mainly exists in the form of V 2 Ti 3 O 9 and V 1.93 Cr 0.07 O 3 in CVTP and V 2 TiO 5 in reduced CVTP. The V-bearing spinels on the grain boundaries with fragmentized and prismatic structure restrain the CS of CVTP. The CS of reduced CVTP decreases and RSI increases with increasing V 2 O 5 additions. The V 2 O 5 addition facilitates the aggregation and diffusion of metallic iron particles, and the shape of the metallic iron whiskers transform round dot to prismatic. The pores and intervals enlarge, and thickness of lamellar crystals thickens gradually with increasing V 2 O 5 additions. The study could supply the theoretical and technical basis for the utilization of CVTP and other V-bearing ores with COG recyclable technology. KEY WORDS: V 2 O 5 ; oxidation induration; reduction swelling index; coke oven gas; chromium-bearing vanadium titanomagnetite pellets.

Study on Sintering Characteristics of Ultra-Poor Vanadium-Titanium Magnetite

“…However, with the continuous progress of mining and beneficiation technology, a large amount of vanadium-titanium magnetite with a low iron content in the mineral field is worth highlighting. It is estimated that the resources of ultra-poor vanadium-titanium magnetite (PVTM) in the Chengde area exceed 10 billion tons [6][7][8][9]. Through sintering, the PVTM can be used together with a high-grade iron concentrate to produce a man-made rich ore for a blast furnace (BF).…”

Preparation, Sintering Behavior and Consolidation Mechanism of Vanadium-Titanium Magnetite Pellets

“…The phase transition in the oxidation process of VTM pellets is obtained. The reaction in route (1) in Figure 7b is as follows: (Fe2TiO4)x (Fe3O4)1-x +1/4O2=3/2(FeTiO3)2/3x(Fe2O3) 1-2/3x…”

“…Vanadium (V), titanium (Ti), and iron (Fe) are important metal elements recognized worldwide. Vanadium-titanium magnetite (VTM) ore is the main source of V, Ti, and Fe in nature with a high comprehensive utilization value [1][2][3]. China is one of the countries which has the richest resources of VTM in the world.…”

Effect of Cr2O3 on the Kinetics Mechanism and Microstructure of Pellet During Oxidation Roasting Process

“…[5] The Panzhihua-Hongge district, in Sichuan Province, China, is also confirmed to have up to 3.6 billion tons of HCVTM reserves. [6][7][8] Thus, this unique mineral deposit has a total utilization value.…”