Evaluation of Chemical Reagents to Enhance the Dewatering of Fine Coal

Abstract

ABSTRACTCoal dewatering of fine coal is one of the major challenges faced by the coal preparation plants. The plant studied in this research is currently producing a fine coal product with 28% moisture and is required to reduce it to below 17% before this fine stream is blended with rest of the clean coal streams. A lot of dewatering aids such as surfactants, flocculants, and superabsorbent polymers are available on the market to enhance the dewatering process. The research was designed to use various dewatering aids to reduce the moisture content of this fine product without decreasing the production rate. Several commercially available chemical reagents were used to enhance the dewatering of this coal product. These reagents were selected in such a way that they could be grouped into different categories depending on their action. The results showed that the surface tension reducing reagents (STR) have a higher capability of moisture reduction than the coal hydrophobicity modifying (CHM) reagents and commonly used in filtration flocculants. Super absorbing polymers used in the dewatering of fine coal were shown to outperform all the other reagents and seem to be suited for this plant dewatering scenario. A cost-benefit analysis is required to make necessary plant modifications if they are to be used there, however, this was not in the scope of this project.