Energy Assessment of Wood Pyrolysis Coproducts for Drying and Power Generation

Abstract

Carbonization is the process in which wood is heated in a closed environment with a controlled amount of air, producing charcoal as a solid product and secreting water vapor, organic liquids, and noncondensable gases. The burning of these gases generates energy that can be used for the drying wood to be carbonized or for generation of electric power in the carbonization plant itself. The present study had the purpose to conduct an energetic survey of the fractions from charcoal production process, aiming to subsidize and to encourage the technological development of equipment for energetic use of carbonization gases. The results showed that the energy contained in noncondensed gases and in pyroligneous liquid corresponds to a total of 31% of the wood energy used. Two scenarios of synchronizing four kilns were studied in pyrolysis, and a maximum and constant potential of 9.7 MW was obtained in scenario 2. The gas burner was efficient in the emission control, because it reduced CO and CH4 in the ranges of 97–99% and 68–91%, respectively. Thus, the gas burner is a promising technology for reduction of greenhouse gases and generation of thermal energy from carbonization coproducts.

Experimental Research on the Drying Characteristics of Flexible Fibrous Biomass Fuels in the Baffled-Rotary Cylinder

“…During the drying process, the wet experimental materials in the rotary cylinder were heated and dried by conduction and convection heat and mass transfer. In most of the mean residence time, wet materials mainly came in contact with the high-temperature cylinder. , Therefore, the cylinder properties could not be ignored, especially for cylinder temperature. Under different cylinder temperatures (70, 85, 100, 115, and 130 °C), the cylinder was performed with gas temperature of 80 °C, rotational speed of 10 rpm, and gas flow velocities of 0.3 m/s.…”

Potential use of wood pyrolysis coproducts: A review

“…This liquid fraction, in turn, can be separated into two phases, forming the pyroligneous acid (PA) and the insoluble tar (IT). 44 Pyroligneous acid are composed of water (80 $ 90%) and more than 200 different constituents (10%-20%) such as phenolics, ketones, organic acids, furan and pyran derivatives, esters, alcohols, aldehydes, alkyl aryl ether and benzene derivatives, and sugar derivatives, in variable concentrations. 50 Some physical properties such as pH, specific gravity, dissolved tar content are, respectively, within the range of 2-4, 1.005-1.016 g/ml, 0.23-0.89% wt.…”

Furnace-kiln system carbon balance and economic viability for charcoal production on small farm

“…When comparing the GY, with and without CH4 burning, the values of 33.13% with burning and 28.15% without burning were observed, which shows the better performance of the system from an economic point of view, for having a higher productivity, and from an environmental point of view, for the reduction in GHG emissions . The use of the furnace-kiln system in the industry resulted in a CH4 emissions reduction by 89.65% and, due to the CO2 production resulting from the CH4 burning, there was an increase in CO2 emission of 89.93% (Pereira et al, 2017). The present study showed greater efficiency in reducing methane emissions due to the use of advanced carbonization technology and greater control in the charcoal production process.…”

“…reduction and emissions proposed in the Paris Agreement(MMA, 2015). Burning gases technologies for charcoal production should be encouraged, as the production chain has not yet been reached comprehensively and consistently(Pereira et al, 2017) Bailis et al (2013). carried out a life cycle analysis comparing charcoal production with traditional surface circular kiln, which releases GHG directly into the atmosphere, and rectangular kilns equipped with gas flaring systems, as an alternative scenario.…”