Presentation on theme: "Potential of using Organic Fraction of Solid Municipal Waste (OFSMW) for biohydrogen production in South Africa."— Presentation transcript:
Potential of using Organic Fraction of Solid Municipal Waste (OFSMW) for biohydrogen production in South Africa
The need for alternative energy Carbon emissions contributes to greenhouse effects. Currently, 85% of global energy is derived from fossil fuels & crude oil (Das, 2009). The WHO, estimates that 160 000 people die each year from side effects of climate change (WHO, 2 003).
The need for alternative energy: depletion & prices Oil has reached its “Peak” production. This is due to high demands & overuse in global markets. A heavy increase in fuels prices is evidence over the past decades.
Hydrogen as a potential energy source H 2 is abundant, clean, efficient, can be derived from diverse domestic resources. Biomass Hydro Wind Solar Geothermal Coal Nuclear Natural Gas Oil With Carbon Sequestration. Transportation Distributed Generation HIGH EFFICIENCY & RELIABILITY
Energy extracted from OFSMW for H 2 production Substrate typeConversion efficiencySpecific H 2 production OFSMW2.5 mol H 2 /mol glucose 114 ml/g VS added OFSMW1.98 mol H 2 /mol glucose 127 ml/g VS added FW2.1 mol H 2 /mol glucose - FW2.11 mol H 2 /mol glucose 165 ml/g VS added FW0.6-0.9 mol H 2 /mol glucose 28.4-46.3 ml/g VS added FW1.8 mol H 2 /mol glucose 91.5 ml/VS added
Production of OFSMW in South Africa Data from DEA, shows that an estimated 7.88 millions tons of organic waste were generated in South Africa in 2011. Only 35% was recycled. The rest was burnt and disposed on landfills. Poses environments & health risks.
Composition of OFSMW OFSMW consists of food waste, garden waste, paper, other various waste materials. Its generated from household, agricultural & industrial sectors. ComponentC H2H2 O2O2 N2N2 SAsh Food waste486.4188.8.131.52 Paper43.56440.30.26 Cardboard445.9184.108.40.206 Textiles556.6220.127.116.11.5 Rubber7810-2- Leather60811.6100.410 Yard wastes47.86318.104.22.168 Wood49.5622.214.171.124.5
Biohydrogen production processes from OFSMW Under different operational parameters SubstrateInoculumPretreatmentpH rangeOptimal pHTemp oC Reactor typeH 2 yield OFSMW Mixture of deep soil, pig excretes HST5.7_38UASR127 ml/g VS, 99 ml/g VS FWActivated sludge HST6-7.56.539CSTR51-81ml/g VS FW+OMW Activated sludge_4.5-6.56.536CSTR3.4-44 ml/g VS FWAnaerobic sludge HST5-65.555CSTR18-63 ml/g VS FWAnaerobic sludge HST5.5 _ 55CSTR28.4-46.3 ml/g VS
Biohydrogen & Bioelectricity generation from OFSMW: Our laboratory findings Semi-pilot process conducted in 10 L bioreactor (Labfors Infors). Inoculum: 100 o C for 30 minutes. At pH 7.9, 30.29 o C,60 h HRT, and 100 rpm. The bioreactor was flushed with N 2 gas for 10minutes. H 2, CH 2 and CO 2 measured with sensors (Bluesens, Germany).
Biohydrogen & Bioelectricity generation from OFSMW: Laboratory findings Results: Maximum H 2 fraction of 46.72%. H 2 yield of 246.93 ml H 2 /g TVS. Cumulative H 2 volume of 3.12 L No CH4 detected.
Biohydrogen & Bioelectricity generation from OFSMW: Laboratory findings The two-chambered MFC reactor was fabricated using glass material. Electrodes made up of graphite rods (1475 mm 2 cross section). Projected surface area of 2187 mm 2 At pH 7, 30 o C. Fig. 1 Schematic diagram of a MFC cell
Biohydrogen & Bioelectricity generation from OFSMW: Laboratory findings Results: A maximum electrical power density of 210 mW/m 2 was recorded. Current density 73.94 73.94 mA/m 2 COD removal efficiency of 50.12%.
Conclusions 1. BioH 2 scale-up studies using OFSMW coupled with MFC for optimum bioenergy extraction would shorten the timeline: For a more environmentally friendly. Sustainable biohydrogen economy development. 2. BioH 2 from OFSMW will also assists to alleviate environmental hazards.