Enhanced compressive strength of preheated limonite pellets with biomass-derived binders

Abstract

Sodium lignosulfonate (SL) is a powder-like by-product of the pulp and paper industry derived from lignocellulosic biomass. SL can potentially be a low-cost and highly efficient binder for the pelletization of iron ore powder in the ironmaking industry because it is a natural polymer compound containing multiple functional groups, such as hydroxyl, carboxyl, and sulfonic acid. In this paper, the strong organic binder, namely SL, was used to enhance the compressive strength of the limonite pellet, which is required to reduce VOC emission during the iron-making process. The limonite pellets' pellet size variation and compressive strength prepared with SL-based binders were studied at a temperature range from 900 °C −1100 °C. Experimental results showed that the compressive strength of the preheated pellets was the highest at a preheating temperature of 1100 °C, reaching 342.55 N/P which is qualified for the subsequent iron-making process. These experimental results provide essential references for optimizing the preparation of limonite pellets with SL-based binders. Furthermore, this study employed artificial neural networks to process experimental data and generate predicted values for corresponding experimental conditions. The predicted results closely matched the observed values, further assisting enterprises in accelerating their digitization and automation processes.