Effects of ball milling parameters on wood particle size

Abstract

In recent years, Singapore has placed growing priority on the development of biofuels as part of the long-term energy strategy towards a zero-waste nation. Owing to rising energy demand, the conversion of lignocellulose to biofuel has emerged as a viable option for improving energy security and reducing global carbon emissions.

There are several pre-treatment techniques used for biomass refineries to alter the structural and chemical factors of lignocellulosic biomass and increase hydrolysis rates. In this project, the breaking down of cellulose in rain tree wood using ball milling with different energy conditions is studied. The main objective is to reduce the rain tree wood to a size of micrometres for enhanced cellulose accessibility while consuming minimal ball mill energy.

The focus of this project is to maximize the energy efficiency of ball milling with respect to milling kinetics. In this project, the main factors involved in assessing energy efficiency are the speed, time, and milling conditions. The optimal parameters are determined by analysing the results of nine experiments with varying speed and time at dry or wet milling conditions.

Based on data analytical methods such as particle size measurements and energy computations, it can be concluded that wet milling yields higher energy efficiency than dry milling, producing smaller particle sizes with lower energy inputs. Among the dry milling experiments, the optimal parameters for obtaining the smallest size ranges are 800 rpm and 45 mins.