Effects of length-to-diameter ratio, pinewood sawdust, and sodium lignosulfonate on quality of rice straw pellets produced via a flat die pellet mill

Poor pelleting ability of rice straw (RS) discourages its production and utilization as a biofuel. Woody biomass lignin are believed to improve the quality herbaceous agro-residual pellets. This study investigated influence length-to-diameter ratio (L/? = 6 10), pine sawdust (PS) (0, 20, 40 wt%) sodium lignosulfonate (SL) 10 20 on RS pellets produced via mini-pilot scale flat-die pellet mill. L/? positively affected specific energy consumption (SEC) process. PS improved significantly content reduced ash simultaneously, however, it decreased true, bulk densities tensile strength SL influenced physical properties for up 10%. Average unit, bulk, tapped were 1272–1330 kg m?3, 596–687 661–760 4.4–5.6 MPa in 10, respectively. remarkably combustion behavior pellets, however effect was not critical. The SEC process ranged between 1.9 2.7 GJ t?1 2.4–3.6 10. corresponding ratios 3.1–4.4 2.5–3.6, optimal heating value density 15.79 MJ kg?1 9102.81 m?3 6, 15.27 10818.08