Liquefaction of sunflower husks for biochar production Piyo Nontembiso Supervisor :Prof S.Marx Co-supervisor Dr I.Chiyanzu
Presentation Outline • Introduction • Liquefaction: An overview • Objective of the study • Experimental set-up • Methods • Results • Concluding Remarks • References
Introduction • Increased focus on global warming • Development of feasible renewable energy source • Reduction of fossil fuel dependency • Biomass is the third largest energy resource, following oil and coal • Clean fuel because it has negligible sulphur and nitrogen content which results in lower sulphur dioxide and nitrogen oxide than conventional fuels
Liquefaction: An overview Liquefaction: • biomass decomposition reactions carried out in a solvent media at temperature (200- 400°C),Pressure (5 and 20 MPa), alkaline catalysts • Key principle: products with low oxygen content, high heating content & high H/C ratio • Three products are produced during liquefaction Biochar • carbon-rich product and a potential solid fuel • Has numerous uses such as: • can be combusted/gasified for heat and power • activated for adsorption application • applied as a soil amendment • and carbon sequestration agent
Objective of the study • To investigate the effect of solvents, reaction temperature and reaction atmosphere on biochar production during liquefaction of sunflower husks. Experimental setup
Methods Input variables: • Liquefaction temperature 240-320 °C • Liquefaction reaction atmosphere: CO₂ and N₂ • Reaction solvents :water, methanol, ethanol, iso-propanol and n-butanol Analytical techniques used • Proximate analysis • X-ray diffraction • Fourier Transformed Infrared • Scanning electron microscope • Brunauer-Emmet-Teller • Elemental analysis
Results Figure1: Effect of solvent on biochar yields under different Figure 2: Effect of temperature on biochar yields in ( CO₂, N₂) at atmospheres ( CO₂ and N₂) at 280°C different reaction atmospheres
Results continues ………………. Table 1: Elemental analysis of biochar samples under (N₂ and CO₂ atmosphere) Figure 3: FT-IR spectra of sunflower husks and its biochar obtained at different liquefaction temperatures in CO₂ atmosphere ( Raw biomass, 260⁰C, 280⁰C, 300⁰C).
Concluding Remarks • We have demonstrated that biochar properties and yields are a function of production process conditions • The biochar yields were influenced in this order > by temperature > type of the solvent > reaction atmosphere. • The heating value of the biochar is high (26.76 MJ/kg) and comparable to that of conventional fuel such as lignite (25.0 MJ/kg) • This increases its potential to be used as fuel • Sunflower husks is a promising feedstock in the production of useful products such as biochar through liquefaction • Thermochemical conversion of sunflower into solid fuel like biochar may play an important role in solving the growing energy demands
References • Bridgwater, A.V. & Maniatis, K. 2004. The production of biofuels by the thermochemical processing of biomass, in molecular to global photosynthesis. In: Archer M.D. & Barber, J. eds. London UK: IC Press, pp. 521-612. • Brown, R.C. 2011. Thermochemical processing of biomass: Conversion into fuels, Chemicals and Powder, 1st ed., John Wiley & Sons, Ltd. • Demirbas, A. 2009. Current activities and future developments. Energy Conversion and Management, 50: 2782-2801. • Demirbas, A. 2001. A Biomass resource facilities and biomass conversion processing for fuels and chemicals. Energy Conversion and Management, 42:1335-78 • Horio, M. 2009. Development of biomass charcoal combustion heater for household utilization. Industrial and Engineering Chemistry Research, 48(1): 361-372.