Kaji Eksperimental Perilaku Reduksi Briket Campuran Bijih Besi Lhoong Dan Batubara Pada Temperatur Tinggi

Abstract

The steel demand in Indonesia is increasing every year. In 2021, it was recorded that the demand reached 15.9 million tons. Steel is obtained by processing the Iron. One of the well known methods to produce the iron is by reducing the iron ore below the smelted point temperature of iron. The purpose of this study is to find the effect of coal mixture and the effect of temperature variations to the mass loss and to the constant of briquettes reduction rate. The briquettes used have diameter of 40 mm. It was made from the mixture of iron ore, coal and clay under the composition of 90:00:10, 70:20;10 and 50:40:10, compressed at the pressure point of 15 tons. The test was begun by heating the furnace to the reduction temperature (950 °C, 1050 °C, 1150 °C), then the briquettes were placed into the briquette container. The container was connected to a digital scale, and then it was placed into the reduction furnace. The measurement of mass loss was automatically carried by using a computer that had been connected directly to the scale. The amount of coal in the briquettes greatly affects the reduction of briquettes’ mass due to the reducing gas of CO that was excessively formed during the reaction process of coal carbon with CO₂. The reaction of CO reducing gas formation is an endothermic reaction, therefore it requires high temperature in the process. Briquettes with a composition of 50:40:10 which are reduced at the temperature of 1150 °C experience the highest number of mass reduction and reduction rate constants, each of those are 39,37% and 3,6672/s.