Effects of parameters on cashew nutshell and cassava binder briquettes densification: Structural equation modelling

Abstract

Densification improves the properties of loose biomass for use as fuels, and the process is a complex technological problem involving the interaction of variables that are interdependent on one another. The effects of process variables (pressure and dwell time) and a material variable (percentage binder, particle size, and mass) on the density of cashew nutshell and cassava binder briquettes were investigated using structural equation modelling (SEM) with the help of AMOS version 23 software. A furnace was used to carbonize cashew nut shells at temperatures of 250°C. The pulverized charcoal from the carbonization process was used to create briquettes with cassava paste as the binding medium. Different particle sizes of 0.5 mm, 1 mm, and 2 mm were used to create briquettes. Different compaction pressures (9.81 MPa, 19.6 MPa, and 29.42 MPa) were used in the absence and presence of various binder ratios (10%, 20% and 30%). SEM analysis found that factors pressure ((Path coefficient (b) = 493), binder percentage (b = 0. 406), mass (b = 0.257) and dwelling time (b = 0. 173) positively influence the density of cashew nutshell and cassava binder briquettes and conversely for particle size (b = - 0.505, C.R = - 6.010). In addition, SEM model showed that a particle size has the strongest effects on the density of the briquettes followed by compacting pressure and thirdly binder percentage. This study provides a better understanding of some of the factors that influence making of briquettes from cashew nutshell and cassava binder.