Impact of Wood Moisture in Charcoal Production and Quality

Abstract The charcoal production when performed in woods with high moisture content negatively impacts the pyrolysis and causes an increase of greenhouse emissions. The aim of this study was to investigate the effects of moisture on the production and quality of charcoal for the pig iron industry. The slow pyrolysis of Eucalyptus sp. was carried out in four different wood moistures, 0, 20, 40 and 60% (dry base). The charcoal and gas yield decreased according to the increase of wood moisture. On the other hand, the bio-oil yield and charcoal friability increased along with the moisture content. The proximate analysis, bulk density and higher heating value of the charcoal were not influenced by the moisture content. The use of wood with moisture content below 20% in the production of charcoal is an alternative to improve productivity, contributing for the economic sustanainability of this sector.

摘要：若采用高含水率木材制备木炭，会对热解过程产生不利影响，同时加剧温室气体排放。本研究旨在探究木材含水率对生铁工业用木炭生产及品质的影响。本实验以桉属（Eucalyptus sp.）木材为原料，设置0、20、40、60%（干基）四种含水率梯度开展慢速热解（slow pyrolysis）实验。结果表明，木炭与气体产率随木材含水率升高而降低；与之相反，生物油产率与木炭易碎性则随含水率提升而升高。此外，木炭的工业分析（proximate analysis）指标、堆积密度（bulk density）与高位发热量（higher heating value）均不受木材含水率的影响。在木炭生产中使用含水率低于20%的木材，可作为提升生产效率的可行方案，有助于该行业的经济可持续性。