Effects of Kraft Lignin and Corn Residue on the Production of Eucalyptus Pellets

Abstract

Pellets have become an important renewable energy source. Aiming to contribute for diversifying the Brazilian energy matrix, the goals of this work were to evaluate the quality of the pellets of lignocellulosic residues (Eucalyptus and corn) produced with the addition of different percentages of Kraft lignin. For the production of pellets, mixtures of wood with bark of a Eucalyptus urophylla and Eucalyptus grandis, and corn residue were used as raw material. The proportions of corn residue in the mixture were 0, 20, 25, and 30% (w/w). Except for the control (0% lignin), 2 and 5% (w/w) Kraft lignin were added to a dry mass of raw material in the 4 different mixtures. Pellets were produced in a laboratory press pelletizer with horizontal circular array. The following properties of the pellets were evaluated: proximate analysis, high heating value (HHV), elementary analysis, energy density, bulk density, diameter and length, hardness, mechanical durability, and fine content. The pellets were classified according to European marketing standards. The addition of Kraft lignin to eucalyptus and corn residue pellets contributed to improving the physical and mechanical pellet properties, as regards the bulk density, mechanical durability, and fine content, allowing the transportation of a greater amount of mass and energy, besides maintaining the integrity of the biofuels during handling and use. The mixing of eucalyptus with corn residue is an effective way to optimize properties of biomass solid fuel. The treatment with higher corn addition, in relation mechanical properties, showed a better performance in accordance with the European standards. The mechanical properties were above to 97.5%, besides that has no impact from the addition of Kraft lignin. The addition of up to 20% of corn residue has the potential to improve physical and mechanical pellet quality, with or without Kraft lignin addition. Thus, similar amounts to that of the treatment with the proportion of 80% eucalyptus and 20% corn residue can be a viable alternative to the production of pellets.

Lignin Use in Enhancing the Properties of Willow Pellets

“…Additionally, it has been reported that most pellets with lignin as an additive contained more ash than the control pellets, adversely affecting the fuel pellet combustion (Table 3). However, eucalyptus pellets containing 2% and 5% kraft lignin had lower ash than the control [53], while eucalyptus pellets containing 1% and 2% lignosulfonate in a different study [54] reported an inconsistent effect on pellet ash. Regarding moisture absorption, adding lignin to spruce resulted in an increase in moisture absorption at equilibrium compared to when lignin was not added [55].…”

Amazon Natural Fibers for Application in Engineering Composites and Sustainable Actions: A Review

“…These lignocellulosic residues emerge as a promising option to serve as an alternative source of energy, being repurposed as raw materials in a differentiated manner. For instance, they can be used for heat or electricity generation, or for the production of materials and chemicals, following the principles of green chemistry that advocate for the use of renewable raw materials [33]. Another alternative to address the excessive accumulation of plant residues is the utilization of these residues as fillers in polymeric composites and other Eng 2024, 5 conventional engineering materials.…”

Structural and chemical characterization of lignin and hemicellulose isolated from corn fibers toward agroindustrial residue valorization

“…Lignin is a macromolecule that constitutes part of the chemical composition of CF; furthermore, lignin permits expansion of the bioproduct possibilities to monomers, polymers and chemicals of high-value added (Boerjan et al 2003;Beramendi-Orosco et al 2004;Gillet et al 2017;Boschetti et al 2019;Barbosa et al 2022). Lignin is currently quantified via the Klason method, in which the extractive-free carbohydrate fraction of biomass is hydrolyzed with acid and the remaining material is determined gravimetrically as lignin.…”