Near infrared spectroscopy as an alternative method to thermogravimetric analysis for evaluation of volatile matter of bamboo wood chips

Bamboo “Dendrocalamus siriceus cl. Phamon” which are planted everywhere in Thailand. It can be used as source of renewable energy. The volatile matter of biomass is considered to be an important parameter for evaluation of the amount of liquid fuel and gas fuel produced by fast pyrolysis and gasification, respectively. It is the specific characteristic of biomass feedstock to indicate whether it is suitable for fast pyrolysis process or gasification. In the future, the volatile matter content in biomass will be used for setting a price of biomass instead of weight. The main objective of this study was to evaluate the volatile matters of bamboo chips using near infrared (NIR) spectroscopy as an alternative to thermogravimetric analysis. The NIR spectra were obtained by scanning of bamboo chips using Fourier transform NIR spectrometer in diffuse reflectance mode. Absorption data was recorded by log 1/R unit. The result showed that bamboo “Dendrocalamus siriceus cl. Phamon” gave volatile matter in range of 68.68-64.48% on as-received and 75.60-68.96% on dry basis. The models were optimized using partial least squares regression (PLSR) with 80% of samples for calibration set and 20% for validation set. The prediction models for volatile matters on as-received provided R2 of 0.874, RMSEP of 0.768%, RPD of 2.82, and bias of -0.0454%, while for volatile matters on dry basis gave R2 of 0.889, RMSEP of 0.665%, RPD of 3.00, and bias of 0.000433%. This indicated high possibility in applying NIR spectroscopy for prediction of volatile matters. This result will benefit for setting a price of biomass and could be used for planning and control in fast pyrolysis and gasification plants.