Torrefaction and Densification of Wood Sawdust for Bioenergy Applications

Abstract

In this study, wood sawdust as waste residue from wood processing mills was pretreated using torrefaction to improve fuel properties and densified to facilitate transportation. Sawdust was torrefied in a fixed bed reactor using inside temperatures (IT) of 230, 260 and 290 °C for 15, 30 and 45 min, residence time. Due to the low calorific value of the treatments, the outside temperature (OT) of the fixed bed reactor was used instead for a fixed duration of 45 min, which resulted in an increase in energy value by 40% for the most severe conditions. The mechanical strength of the pellets was enhanced by adding 20% binder (steam-treated spruce sawdust) to biochar, which improved the pellet tensile strength by 50%. Liquid by-products from the torrefaction process contained furfural and acetic acid, which can be separated for commercial uses. Thermochemical analysis showed better fuel properties of OT torrefied samples such as high fixed carbon (52%), low volatiles (41%) and lower oxygen contents (27%) compared to IT torrefied samples (18, 77 and 43%, respectively). Low moisture uptake of torrefied pellets compared to raw pellets, along with other attributes such as renewability, make them competent substitutes to fossil-based energy carriers such as coal.

Production and characterization of bio-oil from fluidized bed pyrolysis of olive stones, pinewood, and torrefied feedstock

“…BET analysis of the catalyst pellet before and after use. of lignin in torrefied samples can increase when hemicellulose fraction in lignocellulosic biomass decomposed [48].…”

Studi Pengaruh Rasio Co-firing Bahan Bakar Batubara dan Biomassa Tertorefaksi Terhadap Performa Boiler

“…Data bahan bakar pada Tabel 1 diambil dari data batubara untuk PLTU SulSel Barru Unit-2 dan untuk spesifikasi biomassa pada Tabel 2 diambil dari katalog produk milik produsen coconut charcoal, serta referensi [11].…”

Effect of Residence Time On Characteristics of Torrefied Sawdust Produced from Gmelina Arborea (Roxb) Wood

“…Heat radiated from charcoal passed into the upper chamber to roast the sawdust in a limited air supply. The sawdust was heated at torrefaction temperature maintained between a range not exceeding 200 and 300EC, for predetermined resident times of 30, 45 and 60 min 17,18 . At a certain torrefaction resident time, the reactor cover was removed to release a portion of the volatile matter in form of light gases and small amounts of condensable organic compounds visible as condensates on the cover.…”

“…The proximate analysis experiment was carried out according to the procedures and elemental compositions determined by equations presented by Alizadeh et al 17 .…”