Production of fuel briquettes from rice husk–lignite blends

In this study, a lignite sample from Afşin-Elbistan area of Turkey was briquetted using rice husk as additive. The lignite and the rice husk were first briquetted separately without blending under pressures of 280, 555, 830, and 1110 MPa. Lignite–rice husk blends were prepared to contain 2, 5, 10, and 20 wt % rice husk as additive. The blends were also briquetted using three different binder materials (molasses, starch, and black liquor). Shatter index, compressive strength, and water resistance of the formed briquettes were determined and compared. Addition of rice husk into Afşin-Elbistan lignite caused to decrease the water resistance, but improved the mechanical strength of the briquettes. Using binder materials affected both compressive strength and shatter index negatively. But the water resistance of the briquettes increased with increasing binder material concentration. Adding rice husk changed the combustion characteristics of Afşin-Elbistan lignite considerably and shifted its burning profile to lower temperatures.