High reactivity coke production by using by-products of integrated iron and steel plants

Metallurgical coke has duties such as being a heat source, ensuring the strength of charging materials in furnace and reducing iron ore in the blast furnace process which is an important step in the iron and steel production process. Since coke is a carbon containing raw material, CO2 emissions occur in the blast furnace process. Reducing greenhouse gas emissions due to agreements made on a global scale is among the main goals of countries. The purpose of the study is increase the reactivity of coke used in the blast furnace, thus reducing the consumption of coke per unit time and therefore reducing CO2 emission. The reactivity of coke is basically increased by 2 methods. In the first method, coke production ise carried out by adding certain catalyst materials to coal blend before the coking process, in the second method, reactive coke is produced by spraying the catalyst solution on the coke surface after coking process. Increasing the reactivity of the coke causes a decrease in the coke strength. This decrease in strength also reduces the efficiency of the blast furnace process. Since the by-products of iron and steel plants have alkali, alkaline earth and transition elements such as Ca, Fe, Na which increase the reactivity of coke, the evolution of these by-products in the coal blend and thus the production of reactive coke was performed within the scope of this study. After many trials of different by-products, blast furnace flue dust with high iron (Fe) content was added to the blend by briquetting with high volatile coal. 10% of the total blend is briquetted coal and 1% of the total blend contains blast furnace flue dust. The main reason for charging the blast furnace flue dust as briquette form is to prevent the decrease in strength caused by the increase in reactivity in coke. In the study, blast furnace flue dust which is one of the by-products of iron and steel plant was evaluated and reactive coke was produced. The reactivity value of the produced reactive coke was approximately 20% higher than the reactivity value of the coke produced without adding blast furnace flue dust. There was no decrease in the strength value of coke. Blast furnace flue dust which is a by-product of iron and steel process was re-evaluated in a process and its reactivity was increased without decreasing the strength value of coke.