Abstract: This invention discloses a process for reducing sulphur dioxide emission from burning coal containing sulphur. In the disclosed process, pulverized combustible materials, such as coal, wood flour, combustible plant, charcoal, etc., and a sulphur trapping agent composition are mixed homogeneously to form an admixture which is ground to powder with dimension from about 30 mesh to about 60 mesh. With an improved roll briquetter of the present invention, briquettes with a microporous surface layer of said admixture powder can be prepared. In such briquettes, the atomic ratio of calcium in the sulphur trapping agent composition to sulphur in the pulverized coal is within the range of from about 1.0 to about 2.0. Microporous pellets of said admixture having opening-porosity are also prepared with conventional roll briquetter. The diameter of the prepared pellets is within the range from about 8 mm to about 20 mm. A layer of said pellets covers the surface of pulverized coal in a burner for combustion.