A Comprehensive Review of Coal Desulfurization Techniques: Flotation Methods and Biobeneficiation
Edy Nursanto (1), Rofa Dzulfikri Bulopa (1,2), Imam Prasetyo (3), Hendy Roesma Wardhana (3), and Shofa Rijalul Haq (1*)

1) Department Mining Engineering, Universitas Pembangunan Nasional Veteran Yogyakarta, Indonesia
* shofa.haq[at]upnyk.ac.id
2) PT Studio Mineral Batubara, Yogyakarta, Indonesia
3) Department Metalurgical Engineering, Universitas Pembangunan Nasional Veteran Yogyakarta, Indonesia

Abstract

This review article critically examines contemporary coal desulfurization methods, with a primary focus on flotation processes and biobeneficiation techniques. The review synthesizes findings from multiple studies that employ various reagents, including biooxidation agents, biosurfactants, and plant extracts, in the desulfurization of coal. These studies demonstrate the potential of alternative reagents, such as continuous flotation systems using palm oil derivatives and biosurfactants from Sapindus rarak, to significantly reduce sulfur content while preserving or enhancing the calorific value of coal. Additionally, the application of biobeneficiation, particularly using mixotrophic bacteria, is explored for its dual capability in sulfur and ash reduction, presenting a promising complementary approach to traditional flotation methods.
The article provides a comparative analysis of these techniques, evaluating the effectiveness of each method under varying conditions, such as pH, flotation time, reagent concentration, and air flow rates. Optimal conditions for maximum sulfur recovery and calorific value retention are identified, offering valuable insights for the development of more efficient desulfurization processes. The review also highlights the environmental benefits of these techniques, emphasizing the importance of selecting environmentally friendly reagents to reduce the ecological impact of coal utilization. This comprehensive analysis aims to inform future research and development efforts, paving the way for more sustainable and effective coal desulfurization strategies that align with global energy and environmental goals.

Keywords: Coal- Flotation- Bioreagent- Desulphurization

Topic: Engineering