Abstract: An apparatus for manufacturing molten iron includes: an iron ore-mixing/pre-reducing furnace receiving and mixing natural iron ore and oxidized iron ore to form a mixture, and heating or pre-reducing the mixture using a reaction gas to form a pre-heated or pre-reduced iron ore; an iron ore reduction furnace receiving the pre-heated or pre-reduced iron ore iron ore and reducing the pre-heated or pre-reduced iron ore using a reduction gas to form a reduced iron ore and produce the reaction gas; a molten gasification furnace receiving coal and the reduced iron ore and producing molten iron and the reduction gas; and an iron ore oxidizing-burning furnace receiving part of the reduced iron ore discharged from the iron ore reduction furnace and oxidizing the received reduced iron ore to produce the oxidized iron ore. The oxidized iron ore is supplied to the iron ore-mixing/pre-reducing furnace.

Abstract: An apparatus for manufacturing molten iron includes: an iron ore-mixing/pre-reducing furnace receiving and mixing natural iron ore and oxidized iron ore supplied from an iron ore oxidizing-burning furnace, and heating or pre-reducing iron ore using flue gas supplied from an iron ore reduction furnace. The iron ore reduction furnace receives pre-processed iron ore discharged from the iron ore-mixing/pre-reducing furnace or partially reduced iron ore, and reduces the iron ore using a reduction gas discharged from a molten gasification furnace that receives coal and some of reduced iron produced by the iron ore reduction furnace and produces molten iron and a reduction gas to be supplied to the iron ore reduction furnace. The iron ore oxidizing-burning furnace receives new iron ore and some of reduced iron and changes the new iron ore into oxidized iron ore including oxygen by burning the new iron ore and the reduced iron with air.

Abstract: A method for determining optimum catalyst particle size for a gas-solid, liquid-solid, or gas-liquid-solid fluidized bed reactor such as a slurry bubble column reactor (SBCR) for converting synthesis gas into liquid fuels considers the complete granular temperature balance based on the kinetic theory of granular flow, the effect of a volumetric mass transfer coefficient between the liquid and the gas, and the water gas shift reaction. The granular temperature of the catalyst particles representing the kinetic energy of the catalyst particles is measured and the volumetric mass transfer coefficient between the gas and liquid phases is calculated using the granular temperature. Catalyst particle size is varied from 20 ?m to 120 ?m and a maximum mass transfer coefficient corresponding to optimum liquid hydrocarbon fuel production is determined. Optimum catalyst particle size for maximum methanol production in a SBCR was determined to be in the range of 60-70 ?m.