New metallization technology based on equipment from small blown-out blast furnaces

Abstract

The increasing need for clean metallic charge materials in quality metallurgy has given ~ise to the problem of developing lacilities tot the direct reduction of iron in certain regions of our country. Due to the economic situation in Russia, several new criteria have been established for evaluating the cost-effectiveness of building facilities for direct iron reduction. In particular, the following considerations have become paramount:-solving the given problem by rebuilding existing facilities; -minimizing capital expenditures; -achieving compatibility between the direct-reduction subdivision of the factory and its existing infrastructure (especially in regard to energy consumption).These requirements are met by a technology which is based on the metallization of an iron-ore-based raw material and involves the in-furnace conversion of natural gas. The technology includes the following (Fig. 1):-metallization of oxidized pellets in a shaft furnace by products of the conversion of natural gas;heating of the natural gas (to 400~ and circulating top gas (to 900-1000~ and mixing them with oxygen-enriched air in a tuyere before feeding them into the shaft furnace;-removal of dust from the top gas, partial recirculation of the gas, and use of the excess gas to warm the gas heaters or in the fuel system of the combine; -steam-air conversion of natural gas, 40% of the conversion being done in the heaters and 60% in the working chamber of the furnace on metallized pellets; -hot briquetting of the metallized product (if necessary). The technology also makes it possible to use a large portion of the equipment of small blast furnaces that have been removed from service: -the equipment used to receive, transport, store, and batch charge materials and charge them into the furnace;-the gas-cleaning system and water-supply system; -equipment used in compressing and heating the air blast;-oxygen plant (if present).Introduction of the proposed technology will make it possible to:

Physical-Chemical and Pyrometallurgical Estimation of Processing of Complex Ores with Extraction of Iron, Vanadium, Titanium

“…When metallized pellets are melted in an electric arc furnace, the extraction of vanadium into the metal will not exceed 10 %, but special techniques allow up to 90 % [6]. According to IMET UB RAS calculations, highly basic and partially metallized pellets allow up to 90 % vanadium extraction.…”