Briquetting characteristics of some agricultural residues using starch as a binder

Abstract

Briquetting of some agricultural wastes was carried out with the construction of a simple briquetting apparatus and using a 3 x 5 factorial design the effect of mix ratios (40:60; 50:50 and 60:40) and pressures (10, 15, 20, 25 and 30 MPa) on the durability of the briquettes formed was investigated using starch as a binder. The investigation involved the determination of some physical properties, such as moisture content, bulk density and size distribution. The construction and testing of briquette apparatus for making sample briquettes and tumbling formed was carried out so as to evaluate their mechanical performance. It was observed that the mix ratio has a significant influence on the briquettes formed and a highest durability of 89.97% was observed for saw dust at 25 MPa using a mix ratio of 40: 60 (Material: Binder) and least was 37.30% for sorghum residues, mix ratio 60: 40 at 10 MPa. Consequently, the relaxed and final compaction lengths of the briquette were observed to depend on the mix ratio, applied pressure and nature of the material. A SPSS 16.0 software package was used for briquette durability statistical analysis at 5% level of confidence. The results of the investigation clearly indicated the value of the applied pressure in producing briquette of the highest durability for each of the material tested. The variation in the mix ratio of the material to binder provided significant deduction to confirm that best condition of materials and binder mix ratio must be set out to ensure production of durable briquettes. These are parameters of interest to the briquette producers for highest productivity and burning efficiency of the briquette to be produced.

Key Words: Briquettes, Agricultural Residues, Binders, Mix Ratio