การประเมินการปลดปล่อยคาร์บอนไดออกไซด์และประสิทธิภาพพลังงานจากกระบวนการผลิตเชื้อเพลิงอัดแท่งจากใบสับปะรดศรีราชา

Abstract

This research investigated the carbon dioxide (CO₂) emissions and energy efficiency of the production of briquetted fuels including briquetted biomass, torrefied briquetted biomass, and briquetted biochar, produced at both laboratory and pilot scales, using Sriracha pineapple leaves. The results showed that briquetted biomass production led to low CO₂ emissions and high energy efficiency of 2.31 kgCO₂-eq and 52.38%, respectively. However, this type of fuel had a low heating value, a large quantity was thus required for effective use. In contrast, the torrefied briquetted biomass and briquetted biochar had higher heating values but resulted in increased CO₂ emissions and lower energy efficiency. These were due to the high energy consumption required for biomass energy decomposition, especially in biochar production through pyrolysis which involves high temperatures. After that, the biochar production process was scaled up to the pilot scale using a 200-liter kiln equipped with a condensation system for condensing volatile gases into wood vinegar and recirculating the remaining non-condensable gases as co-fuel. The energy efficiency of the process was improved compared to laboratory-scale biochar production, which did not reuse the biomass gases. This demonstrated a more efficient energy utility. Additionally, this process emitted less CO₂ than other methods due to partial carbon sequestration in the form of wood vinegar and reduced fuel consumption for heating during pyrolysis. Biochar could have the potential use of biochar as a carbon sink when applied as a soil amendment as well. The findings from this study provided preliminary information for selecting appropriate briquetted fuels production methods, according to production and utilization objectives for both laboratory and industrial scales.