liquefaction of sunflower husks for biochar production piyo nontembiso supervisor :prof s.marx...
TRANSCRIPT
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.