Production of wood pellets from forest product waste

Abstract

Wood pellet production is increasing due to lower costs and supply stability as compared to natural gas and has less environmental concerns. A wood pellet is made mechanically from a uniform substance that has initially been hammered and ground into a homogenous dough-like mass by squeezing it through a press into a cylindrical shape. Wood pellets have an approximate size of 6-10 mm in diameter and lengths vary between 10-30 mm usually. The production of wood pellets from biomass is environmentally feasible and sustainable contributing to the economy of North America. Municipal waste is a modern method of energy production and, in addition to wood and agricultural products, municipal waste is the third most important biomass resource for energy production. Torrefaction is another method of converting raw material into a more energy dense fuel that could play a significant role in the production of wood pellets. Biomass fuels have received a lot of attention as a potential alternative to fossil fuels because of their ability to reduce greenhouse gas emissions. Biomass fuels, however, have storage, transportation, and energy density issues. Low density values can reduce energy density, resulting in higher transportation and storage costs. In the world, China is the largest producer of wood pellets, while United States is second followed by Canada and then Vietnam.