Experimental study of torrefied pine as a gasification fuel using a bubbling fluidized bed gasifier

Torrefied biomass has higher C/O ratio, resulting in improved heating value and reduced hygroscopic nature of the biomass, thus enabling longer storage times. In the southeastern United States, pine is has been identified as a potential feedstock for energy production. The objective of this study was to understand the performance of torrefied pine as a gasification fuel in a bench-scale bubbling fluidized bed gasifier. The gasification of torrefied pine was carried out at 790, 935 and 1000 °C and three equivalence ratios (ERs: 0.20, 0.25 and 0.30). The effect of process variables were studied based on i) products yield, ii) syngas composition iii) syngas energy content, and iv) contaminants. The mean concentration of CO increased with an increase in temperature, but was not statistically significant. On the other hand, H2 concentration increased whereas CH4 concentration decreased significantly with an increase in temperature from 790 to 935 °C. Further, with an increase in ER from 0.20 to 0.30, only CO2 concentrations increased in the syngas. Results from torrefied pine were compared with raw pine gasification, and it was observed that torrefied pine gasification led to much higher char yield (more than twice) than pine; however, it produced less than half as much tar.

[1]  Kamil Kwiatkowski,et al.  Biomass gasification: Influence of torrefaction on syngas production and tar formation , 2015 .

[2]  Lei Zhang,et al.  Emissions of SO2, NO and N2O in a circulating fluidized bed combustor during co-firing coal and biomass. , 2007, Journal of environmental sciences.

[3]  Linghong Zhang,et al.  Overview of recent advances in thermo-chemical conversion of biomass. , 2010 .

[4]  G. Krishnan,et al.  Development of Disposable Sorbents for Chloride Removal from High-Temperature Coal-Derived Gases , 1996 .

[5]  T. G. Bridgeman,et al.  An investigation of the grindability of two torrefied energy crops , 2010 .

[6]  A. Demirbas,et al.  Sustainable cofiring of biomass with coal , 2003 .

[7]  Chao Gai,et al.  Distribution of sulfur species in gaseous and condensed phase during downdraft gasification of corn straw , 2014 .

[8]  S. Mani,et al.  Impact of torrefaction on the grindability and fuel characteristics of forest biomass. , 2011, Bioresource technology.

[9]  Sushil Adhikari,et al.  Effects of Temperature and Equivalence Ratio on Pine Syngas Primary Gases and Contaminants in a Bench-Scale Fluidized Bed Gasifier , 2014 .

[10]  P. Lv,et al.  An experimental study on biomass air-steam gasification in a fluidized bed. , 2004, Bioresource technology.

[11]  Kj Krzysztof Ptasinski,et al.  A review of the primary measures for tar elimination in biomass gasification processes , 2003 .

[12]  Po Chih Kuo,et al.  Gasification performances of raw and torrefied biomass in a downdraft fixed bed gasifier using thermodynamic analysis , 2014 .

[13]  R. Raiko,et al.  Comparing the energy required for fine grinding torrefied and fast heat treated pine. , 2012 .

[14]  René Guyonnet,et al.  Energy requirement for fine grinding of torrefied wood , 2010 .

[15]  Prabir Basu,et al.  Biomass Gasification, Pyrolysis and Torrefaction: Practical Design and Theory , 2013 .

[16]  Katsuya Kawamoto,et al.  Bench-scale gasification of cedar wood--part II: effect of operational conditions on contaminant release. , 2013, Chemosphere.

[17]  R. Bain,et al.  Pilot-Scale Gasification of Corn Stover, Switchgrass, Wheat Straw, and Wood: 1. Parametric Study and Comparison with Literature , 2010 .

[18]  P.C.A. Bergman,et al.  Torrefaction for biomass co-firing in existing coal-fired power stations BIOCOAL , 2005 .

[19]  Andrew Narvaez,et al.  Biomass gasification with air in an atmospheric bubbling fluidized bed. Effect of six operational variables on the quality of the produced raw gas , 1996 .

[20]  J. Leahy,et al.  Impact of torrefaction on properties of Miscanthus × giganteus relevant to gasification , 2014 .

[21]  L. Baxter.  Biomass-coal co-combustion: opportunity for affordable renewable energy , 2005 .

[22]  Wei-Hsin Chen,et al.  An evaluation on improvement of pulverized biomass property for solid fuel through torrefaction , 2011 .

[23]  Martin Strandberg,et al.  From torrefaction to gasification : Pilot scale studies for upgrading of biomass , 2015 .

[24]  N. Doassans-Carrère,et al.  REVE — a new industrial technology for biomass torrefaction: pilot studies , 2014 .

[25]  Amie D. Sluiter,et al.  Determination of Structural Carbohydrates and Lignin in Biomass , 2004 .

[26]  Peter McKendry,et al.  Energy production from biomass (Part 1): Overview of biomass. , 2002, Bioresource technology.

[27]  L. I. Darvell,et al.  Combustion and gasification characteristics of chars from raw and torrefied biomass. , 2012, Bioresource technology.

[28]  D McIlveen-Wright,et al.  A technical and environmental analysis of co-combustion of coal and biomass in fluidised bed technologies , 2007 .

[29]  Danielle D. Bellmer,et al.  Gasification performance of switchgrass pretreated with torrefaction and densification. , 2014 .

[30]  Øyvind Skreiberg,et al.  Torrefaction of Norwegian Birch and Spruce: An Experimental Study Using Macro-TGA , 2012 .

[31]  Kj Krzysztof Ptasinski,et al.  More efficient biomass gasification via torrefaction , 2006 .

[32]  A. Ragauskas,et al.  Effect of torrefaction on biomass structure and hydrocarbon production from fast pyrolysis , 2015 .

[33]  Pedro Ollero,et al.  Air—Steam Gasification of Biomass in a Fluidized Bed under Simulated Autothermal and Adiabatic Conditions , 2008 .

[34]  J. V. Doorn,et al.  Ten residual biomass fuels for circulating fluidized-bed gasification , 2001 .

[35]  B. J. Wood,et al.  Development of disposal sorbents for chloride removal from high-temperature coal-derived gases , 1995 .

[36]  Karin Ericsson,et al.  Co-firing - A strategy for bioenergy in Poland? , 2007 .