Ahmad RashediID, Niamat Gul, Majid HussainID2, Rana Hadi3, Nasreen Khan3, SayyadaGhufrana Nadeem, Taslima Khanam1, M. R. M. Asyraf5, Virendra Kumar6
This study was carried out to produce low-emitting biomass pellets biofuel from selected forest trees such as (Cedrus deodara and Pinus wallichiana) and agricultural crop residues
such as (Zea mays and Triticum aestivum) in Gilgit-Baltistan, Pakistan using indigenously
developed technology called pelletizer machine. Characterization, environmental life cycle
impact assessment, and cumulative energy demand of biomass pellets biofuel produced
from selected agriculture crops and forest tree residues were conducted. The primary data
for biomass pellets production was collected by visiting various wood processing factories,
sawmills, and agricultural crop fields in the study area. Biomass pellets are a type of biofuel
that is often made by compressing sawdust and crushing biomass material into a powdery
form. The particles are agglomerated as the raw material is extensively compressed and
pelletized. Biomass pellets have lower moisture content, often less than 12%. Physically,
the produced pellets were characterized to determine moisture content, pellet dimensions,
bulk density, higher heating value, ash content, lower heating value, and element analysis.
A functional unit of one kilogram (kg) biomass pellets production was followed in this study.
The life cycle impact assessment of one kg biomass pellets biofuel produced from selected
agro-forest species revealed environmental impact categories such as acidification (0.006
kg SO2 eq/kg pellets), abiotic depletion (0.018 kg Sb eq/kg pellets), marine aquatic ecotoxicity (417.803 kg 1,4-DB eq/kg pellets), human toxicity (1.107 kg 1,4-DB eq/kg pellets), freshwater aquatic ecotoxicity (0.191 kg 1,4-DB eq/kg pellets), eutrophication (0.001 kg PO4 eq/
kg pellets), global warming (0.802 kg CO2 eq/kg pellets), and terrestrial ecotoxicity (0.008
kg 1,4-DB eq/kg pellets). Fossil fuel consumption was the hotspot source to all environmental impacts investigated. To measure the cumulative energy demand of biomass pellets
made from different agroforestry species leftovers showed that the maximum cumulative
energy was from wheat straw pellets (13.737 MJ), followed by corncob pellets (11.754 MJ).