Coal briquetting for supplying quality fuel to consumers in the Arctic Zone

This study developed a briquetting method for fine-grained lignite and bituminous coal using recycled cardboard as a binder to address environmental and economic challenges in fuel supply. This research is particularly relevant for the Arctic zone of the Republic of Sakha (Yakutia), where coal transported under the Northern Delivery program is subjected to prolonged storage and repeated handling, leading to particle fragmentation and reduced combustion efficiency. We propose a decentralized processing solution to convert coal fines into briquettes directly at consumption sites, thereby decreasing reliance on centralized supply chains and enhancing the energy security of remote communities. For this study, feedstock consisted of lignite from the Kangalas deposit and bituminous coal from the Denisovskoye deposit. The influence of binder content on the mechanical strength and calorific value of the briquettes was investigated to establish optimal compositions and production parameters. The results indicate that incorporating 9–13 % cardboard (by dry coal mass) for lignite and 9–10 % for bituminous coal yields briquettes with a compressive strength exceeding 7.8 MPa, although a marginal reduction in heat of combustion was observed. The process operates at ambient temperature without external energy input, which is a critical advantage for Arctic implementation. Furthermore, while briquette strength decreases after water exposure, this can be mitigated by covered storage. Therefore, the proposed briquetting technology is suitable for implementation in remote settlements dependent on the Northern Delivery Program, as processing coal fines locally can reduce transport losses and reintroduce fine coal fractions into the fuel cycle. To this end, a modular, seasonally operable production unit adaptable to local coal varieties is recommended to maximize feasibility in isolated Arctic regions.