Reduced Local Emissions and Long-term Carbon Storage through Pyrolysis of Agricultural Waste and Application of Pyrolysis Char for Soil Improvement

Abstract The direct storage of biologically stable pyrolysis char in soils is discussed as a low-tech below zero emission technology option with positive side-effects. A rotary kiln pyrolysis process, which has already been successfully applied at industrial scale before, is selected as the reference technology. Cotton stalks are considered as feed for the pyrolysis plant, representing a typical agricultural by-product with short rotation times. The plant efficiency is calculated for the case that the thermal energy that runs the pyrolysis process is provided by combustion of a part of the pyrolysis gas, while pyrolysis oil is provided as a product. The remaining pyrolysis gas powers a gas engine-based combined heat and power (CHP) island. 100% of fuel power fed with the biomass are distributed as follows (based on the lower heating value): 52% stay in the biochar, 13% in the pyrolysis oil, 10% are converted to electric power in the CHP plant, and, finally 15% are available as heat at a temperature span between forward and back flow of 100 °C/70 °C and may be used on-site for drying of agricultural products and pyrolysis feedstock. A rough comparison of the proposed process to biomass power generation substituting coal-fired power generation shows that the net effects on the carbon balance are comparable, but additional carbon-neutral energy streams are generated in the pyrolysis case.

[1]  D. C. Reicosky,et al.  Impacts of Sixteen Different Biochars on Soil Greenhouse Gas Production , 2009 .

[2]  Andre Peters,et al.  Impact of biochar and hydrochar addition on water retention and water repellency of sandy soil , 2013 .

[3]  Saran Sohi,et al.  Biochars in soils: new insights and emerging research needs , 2014 .

[4]  Hui Liu,et al.  Distribution, utilization structure and potential of biomass resources in rural China: With special references of crop residues , 2008 .

[5]  Werner Boie.  Vom Brennstoff zum Rauchgas : Feuerungstechnisches Rechnen mit Brennstoffkenngrössen und seine Vereinfachung mit Mitteln der Statistik , 1957 .

[6]  Jeff Baldock,et al.  Chemical composition and bioavailability of thermally altered Pinus resinosa (Red pine) wood , 2002 .

[7]  P. Jansens,et al.  Biomass combustion in fluidized bed boilers: Potential problems and remedies , 2009 .

[8]  Hermann Hofbauer,et al.  Development and Application of a Simulation Tool for Biomass Gasification Based Processes , 2008 .

[9]  S. Brandani.  Carbon Dioxide Capture from Air: A Simple Analysis , 2012 .

[10]  Christine L. Goodale,et al.  Fate of soil‐applied black carbon: downward migration, leaching and soil respiration , 2010 .

[11]  M. Velde,et al.  A quantitative review of the effects of biochar application to soils on crop productivity using meta-analysis , 2011 .

[12]  Bruno Glaser,et al.  Genotoxic and phytotoxic risk assessment of fresh and treated hydrochar from hydrothermal carbonization compared to biochar from pyrolysis. , 2013, Ecotoxicology and environmental safety.

[13]  K. Spokas.  Review of the stability of biochar in soils: predictability of O:C molar ratios , 2010 .

[14]  Douglas L. Karlen,et al.  Biochar impact on nutrient leaching from a Midwestern agricultural soil. , 2010 .

[15]  Carol Skelly,et al.  The World and United States Cotton Outlook , 2014 .

[16]  Kuichuan Sheng,et al.  Characterization of Biochar Properties Affected by Different Pyrolysis Temperatures Using Visible-Near-Infrared Spectroscopy , 2012 .

[17]  S. De Neve,et al.  Interactions between biochar stability and soil organisms: review and research needs , 2013 .

[18]  F. A. Ahmed,et al.  Biochemical studies on some cotton by products Part I- Chemical constituents and cellulose extraction of Egyptian cotton stalks , 2010 .

[19]  G. Boyle.  Renewable Energy: Power for a Sustainable Future , 2012 .

[20]  C. Atkinson,et al.  Potential mechanisms for achieving agricultural benefits from biochar application to temperate soils: a review , 2010, Plant and Soil.

[21]  Bernd Marschner,et al.  Interactive priming of black carbon and glucose mineralisation , 2004 .

[22]  Mustafa Usta,et al.  Removal of methylene blue from aqueous solution using cotton stalk, cotton waste and cotton dust. , 2010, Journal of hazardous materials.

[23]  Li Hua,et al.  Impacts upon soil quality and plant growth of bamboo charcoal addition to composted sludge , 2012, Environmental technology.

[24]  Mark H. Engelhard,et al.  Oxidation of Black Carbon by Biotic and Abiotic Processes , 2006 .

[25]  D. Laird,et al.  Short-term CO2 mineralization after additions of biochar and switchgrass to a Typic Kandiudult ☆ , 2010 .

[26]  M. Fowles.  Black carbon sequestration as an alternative to bioenergy , 2007 .

[27]  J. Sahu,et al.  Effect of process parameters on production of biochar from biomass waste through pyrolysis: A review , 2016 .

[28]  Paul Blackwell,et al.  Effect of banded biochar on dryland wheat production and fertiliser use in south-western Australia: an agronomic and economic perspective , 2010 .

[29]  Sun Yadong,et al.  Thermal Behaviour of Corn/Cotton Stalk Blends during Co-pyrolysis , 2015 .

[30]  I. Obernberger,et al.  Physical characterisation and chemical composition of densified biomass fuels with regard to their combustion behaviour , 2004 .

[31]  H. Hofbauer,et al.  Rotary kiln pyrolysis of straw and fermentation residues in a 3 MW pilot plant – Influence of pyrolysis temperature on pyrolysis product performance , 2012 .

[32]  A. Zimmerman,et al.  Abiotic and microbial oxidation of laboratory-produced black carbon (biochar). , 2010, Environmental science & technology.

[33]  F Worrall,et al.  Charcoal addition to soils in NE England: a carbon sink with environmental co-benefits? , 2011, The Science of the total environment.

[34]  Johannes Lehmann,et al.  Black carbon decomposition under varying water regimes. , 2009 .

[35]  Waqas Ahmad,et al.  Short-term biochar-induced increase in soil CO2 release is both biotically and abiotically mediated , 2011 .

[36]  Bin Wang,et al.  Characterization of biochars produced from seven biomasses grown in three different climate zones , 2015, Chinese Journal of Geochemistry.

[37]  B. Sanjeeva Reddy,et al.  Biochar Production Technology for Conversion of Cotton Stalk Bioresidue into Biochar and its Characterization for Soil Amendment Qualities , 2013 .