Briquette making business is not widely popular in Northern Nigeria, even though it plays a vital role in enhancing the efficient use of solid fuels in the region. The study aimed to produce bio-coal briquettes from low-rank coal and several biomasses under optimal conditions. Briquette produced using a manually operated briquetting machine was tested to evaluate the impact of the briquettes’ combustion and physicochemical properties with respect to coal-biomass variation ratio, gasification temperature and compressive strength. Based on the experimental data, mathematical models were developed to predict the gross caloric value, ash content, moisture content, and relaxed density. To streamline repetitive tasks and lower experimental costs, Design Expert software was used to refine and optimize the briquetting process. Results of the study effectively revealed the impact of each dependent variable on achieving optimal bio-coal briquette production. The optimized results indicated that the calorific value increased from (27.10 to 27.74) MJ/kg, while the volatile matter content rose from (41.4 to 47.94) % by weight. Ash content and moisture content were reduced from (7.31 to 6.35) % and (11.9 to 9.8) % by weight respectively, while relaxed density and compressive strength were adjusted to meet target ranges of (0.8 to 1.09) KN/m2 to (0.9 to 1.99) m3/Kg respectively.The newly produced bio-coal briquette represents an improved, environmentally friendly solid fuel that can be effectively used in any type of charcoal stove.

Demirbas, A. (2003). Sustainable co-firing of biomass with coal, Energy Convers. Manag., 44 (2003) 1465-1479 Fadli, M., Kamal, D. M., & Adhi, P. M. (2019). Analisis SWOT Untok direct co-firing batubara dengan pellet sampah pada boiler tipe CFBC, Politeknologi, 18 (3) (2019) 271-280. Gungor, A. (2013). Simulation of co-firing coal and biomass in circulating fluidized beds, Energy Conversion and Management, 65, 574-579. IEA Bioenergy. (2022). IEA Bioenergy annual report 2021. Available at https://www.ieabioenergy.com/blog/publications/iea-bioenergy-annual-report-2021/. Jiang, Y., Mori, T., Naganuma, H., & Ninomiya, Y. (2022). Effect of the optimal combination of bituminous coal with high biomass content on particulate matter (PM) emissions during co-firing Fuel, 316, 123244. Josephat K. T. (2016). Influence of processing conditions on the quality of briquettesproduced by recycling charcoal dust. International Journal of Energy and Environmental Engineering https://doi.org/10.1007/s40095-018-0275-7 Liu, Z., Saydaliev, H. B., Lan J., Ali, S., & Anser, M. K. (2022). Assessing the effectiveness of biomass energy in mitigating CO2 emissions: Evidence from Top – 10 biomass energy consumer countries. Renewable energy, 191, 842 – 851. Mangalla, L. K., Balaka, R., Sudarsono, K., &Amiruddin, T. (2010). Combustion Characteristics of Briquettes from Carbonized Rice Husk and Teakwood Blended, Proceeding of Thermofluid Conference in Gadjah Mada Univeristy, Indonesia. Morrison, B., & Golden, J. S. (2017). Life Cycle assessment of co-firing coal and wood pellets in the Southeastern United States, J, Clean. Prod, 150 (5) (2017) 188-196. Nudria, N. A., Ghania, W.A.W.A.K., Bachmann, R. T., Baharudin, B. T. H. T., Nge, D. K. S., Said, S. Md., &Aizat, N. (2021). Co-combustion of oil palm trunk biocoal/sub-bituminous coal fuel blends, Energy Convers, Manag. X. 10 (2021) 100072. Roni, M. S., Chowdhary, S., Mamun, S., Marufuzzaman, M., Lein, W., & Johnson, S. (2017). Biomass co-firing technology with policies, challenges, and opportunities: A global review, Renew. Sustain. Energy Rev., 78 (5) (2017) 1089-1101. Saleem, M. (2022). Possibility of utilizing agriculture biomass as a renewable and sustainable future energy source. Heliyon, 8, Article e08905. Sidiq, A. N. (2022). Pengaruh co-firing biomass terhadapefisiensi boiler PLTU batubara, 11 (1) (2022). 21-31. Spiegl, N., Long, X., Berrueco. C., Paterson, N., & Millan M. (2021). Oxy–fuel co–gasification of coal and biomass for negative CO2 emissions. Fuel, 306, 121671. Yan, P., Xiao, C., Xu, G., Li, A., Piao, S., & He, N. (2020). Biomass energy in China’s terrestrial ecosystems: insights into the nation’s sustainable energy supply. Renewable and Sustainable Energy Reviews, 127, Article 109857. Zhang, X., Li, K., Zhang, C., & Wang, A. (2020). Performance analysis of biomass gasification coupled with a coal-fired boilers system at various loads. Waste Management, 105, 84-91.