Organic Waste Conversion by Torrefaction Pretreatment

Saifone Harnchanaphol, Kittisak Khuwaranyu, Duangkamol Ruen-ngam


This research aimed to demonstrate the thermal pathway (torrefaction technology) to convert organic waste to be biochar/biocoal. Organic waste (cabbage) from Nonthaburi fresh market, Thailand was used as raw material. Torrefaction technology was processed in horizontal cylindrical batch reactor with Nitrogen gas purging during doing experiment. Temperature profile was preliminary checked to find out lag time. Amount of loaded weight and particle size of material were preliminary tested. Experimental conditions such as time and temperature were tested at 30 and 60 minutes, and range temperature of 220 to 300°C. Important property of product; calorific value of product in form of high heating value (HHV) and mass yield percentage were measured. The optimal conditions were evaluated with two parameters; increase of HHV compared to reference condition and % mass yield. Increase temperature was significant effect to increase HHV value of biochar. The optimal time and temperature for getting the highest heating value were 60 minutes and 280°C.


Calorific value; Mass yield; Organic waste; Pretreatment; Torrefaction

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Ram LV. and B. Guilberto. 2022. Emissions of greenhouse gases from municipal solid waste management system in Ho Chi Minh city of Viet Nam. Urban Science 6: 78.

Stocker T.F., Qin D., Plattner G.-K., Tignor M., Allen S.K., Boschung J., Nauels A., Xia Y., Bex, P.M.V., 2013. IPCC, Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Midgley Cambridge University Press: Cambridge, UK; New York, NY, USA, 2013.

Gautam S.P., Bundela P.S., Pandey A.K., Awasthi M.K., and Sarsaiya S., 2010. Composting of municipal solid waste of Jabalpur city. Global Journal of Environmental Research 4: 43–46.

Thanomnim B., Papong S., and Onbhuddha R., 2022. The methodology to evaluate food waste generation with existing data in Thailand. Thai Environmental Engineering Journal 36: 1–9.

UNEP (United Nations Environmental Programme). Waste Management in ASEAN Countries: Summary Report. 2017. .

Basu P., 2013. Biomass Gasification, Pyrolysis and Torrefaction, Practical Design and Theory, 2nd Edition. Elsevier., Inc.

Salihu A. and M.Z. Alam, 2016. Pretreatment method of organic wastes for biogas production. Journal of Applied Sciences 16(3): 124–137.

Nitipong S., Suwat N., and Paisan C., 2022. Thermal degradation of cassava rhizome in thermosyphon-fixed bed torrefaction reactor. Processes 8: 267.

Nitipong S., Suwat N., and Paisan C., 2020. Thermal and torrefaction characteristics of a small scale rotating drum reactor. Processes 8: 489. https://doi:10.3390/pr8040489.

Nitipong S. and S. Unchana. 2015. The effect of biomass bulk arrangements on the decomposition pathways in the torrefaction process. Renewable Energy 81: 679-684.

Kamonwat N., Pongtanawat K., Wasawat K., Parinvadee C., Bunyarit P., Duangta K., and Prasert P., 2021. Upgrading properties of biochar fuel derived from cassava rhizome via torrefaction: Effect of sweeping gas atmospheres and its economic feasibility. Case Studies in Thermal Engineering 23: 100823.

Chadatip L., Kamonwat N., Sanchai K., Anan J., Bunyarit P., 2022. Enhancing lignocellulosic energetic properties through torrefaction and hydrothermal carbonization processes. Biomass Conversion and Biorefnery.

Jakkrit S., Kittisak K., and Duangkamol R., 2022. Simultaneous drying and torrefaction pretreatment of organic waste for upgrading value, International Energy Journal 22: 157 – 166.

ASTM International. (2004). Standard Test Method for Ash in Wood; ASTM E 711, ASTM International, Pennsylvania, USA.

Peng H.J., Bi T.H., Sokhansanj S., and Lim C.J., 2012. A study of particle size effect on biomass torrefaction and densification. Energy and Fuels 26: 3826-3839.

William S.M., Michael J.A.J., Piroska S., Gabor V. and Birbala Z., 1992. Formation of charcoal from biomass in a sealed reactor. Industrial and Engineering Chemistry Research 31: 1162-1166.

Medic D., Darr M., Shah A., Potter B., and Zimmerman J., 2012. Effects of torrefaction process parameters on biomass feedstock upgrading. Fuel 91: 147–154.

Wei-Hsin C., Wen-Yi C., Ke-Miao L., and Ying-Pin H., 2011. An evaluation on improvement of pulverized biomass property for solid fuel through torrefaction. Applied Energy 88: 3636–3644.

Wang L., Barta-Rajnai E., Skreiberg Ø., Khalil R., Czégény Z., Jakab E., Barta Z., and Grønl M., 2018. Effect of torrefaction on physiochemical characteristics and grindability of stem wood, stump and bark. Applied Energy 227: 137–148.

Morato T., Vaezi M., and Kumar A., 2019. Assessment of energy production potential from agricultural residues in Bolivia. Renewable and Sustainable Energy Reviews 102: 14-23.