Effect of natural additive on pellets physical properties and energy cost

Abstract

This research aimed to study the effect of natural additives on the physical properties and energy costs of bagasse pellets. The raw material used for the production of pellets was sugarcane bagasse. Two different natural additives were used in this research: tea grounds and coffee grounds. Various natural additives content were 1%, 3%, and 5% by weight. Biomass pellets were produced using a flat-die pellet mill machine. The physical properties pellet were determined following the standard method of the Pellet Fuel Institute (PFI) Standard Specification. The results showed that the increase of natural additives at a 5 % increase in the bulk density of bagasse by 3.65% for tea ground, and 4.24% for coffee ground. Moreover, the significant increase in the heating value of pellets occurred with the amount of a natural additive greater than 3% by 6.69% for tea ground, and 8.02% for coffee ground. Furthermore, the physical and thermal properties of bagasse pellets with additives as coffee grounds was revealed higher values than tea grounds. On the other hand, the addition of tea grounds and coffee grounds in bagasse pellets does not affect the durability of the pellet. The results indicated that the tea grounds and coffee grounds were able to improve bulk density and heating value of pellets, but it does not affect the pellet durability. Energy cost analysis, the amount of added natural additive at 5% cased the decrease in energy costs for the production process of 4.47% for tea ground and 7.34% for coffee ground. Thus, the optimum amount of natural additive to improve bagasse pellets in this research was 5%. From this research, the tea grounds and coffee grounds could be a suitable natural additive for bagasse pellets in the future.