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RE technology options:. Hydroelectric Solar Wind Geothermal Marine (Wave and Tidal) Biofuels ( Biomass , Bioethanol and Biodiesel ). Biodiesel. Biodiesel can be used in compression ignition engines with little or no modifications.
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RE technology options: • Hydroelectric • Solar • Wind • Geothermal • Marine (Wave and Tidal) • Biofuels(Biomass , Bioethanoland Biodiesel )
Biodiesel Biodiesel can be used in compression ignition engines with little or no modifications. Biodiesel is derived from renewable lipid sources, such as vegetable oil or animal fat. Biodiesel is a mixture of mono-alkyl esters of long chain fatty acids.
Biodiesel production (traditional method) Biodiesel is made by chemically combining any natural oil or animal fat (major component of which is triglyceride) with an alcohol (methanol / ethanol / iso-propanol) in the presence of a cataylst (NaOH or KOH) triglycerids methanol methyl Ester (biodiesel) glycerol (glycerin) + + KOH This process is known as transestrification.
Biodiesel production (traditional method) KOH Methanol Glycerol Biodiesel: mixture of methyl esters Triglyceride Transestrification is a reaction of an ester with an alcohol to form a different ester.
Triglyceride Glycerol
Free fatty acid (FFA) to biodiesel H2SO4 Free Fatty Acid Methanol Methyl ester Water This process is known as estrification (which is a reaction of an acid with an alcohol to form an ester). NaOH Na Free Fatty Acid Base Soap Water This process is known as saponification, in which soap is produced.
Biodiesel feedstock Vegetable oils: - Rape seed/Canola (> 80%) - Soybean (USA, Brazil) - Cotton seed (Greece) - Palm (Malaysia) - Peanut - Sunflower (Italy, FranceSouth) - Linseed & Olive (Spain) - Safflower - Coconut - Jatropha (Nicaragua) - Guang-Pi (China) Animal fats: - Beef tallow (Ireland) - Lard - Poultry fats Waste oils: - Used frying oils (Austria) Other feed stocks: - Algae
Biodiesel production process (5 to 25% FFA)
Biodiesel blends used in diesel engines B2 – 2% biodiesel and 98% petro diesel B5 – 5% biodiesel and 95% petro diesel B20 – 20% biodiesel and 80% petro diesel http://www.mechanicalengineeringblog.com/tag/biodiesel-chemistry
Biodiesel from algae Claimed output of 10,000 gallons of biodiesel per hectare per year.
Biodiesel from algae 10,000 gallons of biodiesel per hectare per year = 37854 litres per 2.47 acres per year = 15325 litres per acre per year = 15325 / 160 litres per perch per year = 96 litres per perch per year = 96 /12 litres per perch per month = about 8 litres per perch per month Claimed output of 10,000 gallons of biodiesel per hectare per year.
Algae biodiesel life cycle Algae harvesting from habitat Culture maintenance/storage Conversion to biodiesel Growth in open pond Transportation and distribution Harvesting customer Separation of cell components Combustion in vehicles Carbohydrate and protein contents K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle Algae harvesting from habitat Partial treatment of wastewater Culture maintenance/storage Manufacture / construction of open pond Growth in open pond Acquiring resources of manufacture Manufacture / maintenance of equipment Harvesting Separation of cell components Crude oil drilling Crude oil refining Hexane purification Carbohydrate and protein contents K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle HCl production Salt mining Natural gas and methane extraction Sodium methoxide Natural gas and methane refining Conversion to biodiesel Methanol production Metal mining Catalyst production Salt mining NaOH production K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle Manufacture / maintenance of equipment Acquiring resources of manufacture Transportation and distribution customer Crude oil drilling Crude oil refining Combustion in vehicles K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle Algae harvesting from habitat When harvested, there is 0.05% algae in wastewater. It has to be brought to 91% algae in wastewater (required by the hexane extraction step). This is achieved by a dewatering process (filtration or centrifugation) followed by drying in a natural gas fired dryer. Culture maintenance/storage Growth in open pond Harvesting Separation of cell components Hexane purification Algae dewatering is the most significant energy sink in the entire process. Carbohydrate and protein contents K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Algae biodiesel life cycle In most algae species, there is typically a larger percentage of carbohydrates than lipids in an algae cell. With lipid removed to produce biodiesel, the remaining carbohydrates makes an excellent feedstock for bioethanol. Every 24 kg of algal biodiesel produced (one functional unit,1,000 MJ algae biodiesel), 28.1 kg carbohydrates and cellulose coproduct are also produced. With less than 2% lignin, bioethanol processing becomes more favourable. K Sander & GS Murthy from Int J Life Cycle Assess (2010) 15:704–714
Life-cycle assessment (LCA) LCA is a tool to assess the potential environmental impacts of product systems or services at all stages in their life cycle – from extraction of resources, through the production and use of the product to reuse, recycling or final disposal.
Limitations of LCA: some examples • Drawing the boundaries • Cradle to Gate or Cradle to Grave? Life Cycle Assessment (LCA) 21
Life-cycle assessment (LCA) transport supply manufacturing disposal packaging Use Cradle to Gate (4 stages) Cradle to Grave (6 stages)
Limitations of LCA: some examples • Weights given to different impacts • What is more important? Use of water resources or CO2 emissions? • Drawing the boundaries • Cradle to Gate or Cradle to Grave? • Do we consider supporting activities for the system? • Example: a warehouse stores the product. Direct energy consumption for the warehouse should be part of the system, but emissions associated with garbage pickup for the facility ???? Life Cycle Assessment (LCA) 23
An example life-cycle assessment: The 1.7 kg microchip: Environmental implications of the IT revolution One 32 MB DRAM chip (weight = 2 gram) 1600 g of fossil fuels 71 g of chemicals 700 g of elemental gases (mainly nitrogen) 32,000 g of water by Eric D. Williams, Robert U. Ayres, and Miriam Heller, The 1.7 Kilogram Microchip: Energy and Material Use in the Production of Semiconductor Devices. Environmental Science & Technology (a peer-reviewed journal of the American Chemical Society), 2002, 36 (24), pp 5504–5510 Source: http://www.enviroliteracy.org/subcategory.php/334.html
Life cycle assessment of biodiesel production from free fatty acid-rich wastes • Biodiesel production systems considered: • - Acid-catalyzed esterification followed by alkali-catalyzed transesterification of waste vegetable oils (used cooking oil) • Esterification and transesterification of beef tallow • Esterification and transesterification of poultry fat • Acid-catalyzed in-situ transesterification of sewage sludges J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Life cycle assessment of biodiesel production from free fatty acid-rich wastes • Impact potentials evaluated: • - Global warming (GWP) in kg CO2 eq. • - Acidification (AP) in kg SO2 eq. • - Eutrophication (EP) in kg PO43- eq. • - Ozone layer depletion (ODP) in mg CFC-11 eq. • Photochemical oxidant formation (POFP) in kg C2H4 eq. • Cumulative non-renewable energy demand (CED) in GJ eq. J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Electricity production Thermal energy production Water suppy Chemicals production Biodiesel production system Other inputs FFA-rich waste Transportation rendering Wastes Transportation Esterification Waste management Trans-esterification Transportation Biodiesel Glycerol Other outputs J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Electricity production Thermal energy production Water suppy Chemicals production Biodiesel production system (for sewage sludges) Other inputs FFA-rich waste Wastes Waste management Trans-esterification Transportation Biodiesel Glycerol Other outputs J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Inventory of input data for the production of 1 t Biodiesel waste rendered rendered dried Materials vegetable beef poultry sewage oils tallow fat sludge Lipid feedstock 1205 1015 1013 10,000 kg Methanol 112.67 113.32 99.00 670.18 kg Sulphuric acid 0.15 - - 76.35 kg Calcium oxide 0.10 - - - kg Water 56.08 71.32 32.00 0.88 kg Sodium hydroxide 9.80 4.00 5.00 - kg Sodium methoxide - 11.00 12.00 - kg Phosphoric acid 7.95 - - - kg Hydrogen chloride - 6.00 7.00 - kg Hexane - - - 76.28 kg J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Inventory of input data for the production of 1 t Biodiesel waste rendered rendered dried Energy vegetable beef poultry sewage oils tallow fat sludge Thermal (rendering) 1628.93 - - - MJ Electrical (rendering) 133.12 - - - kWh Thermal (esterification) 222.30 175.94 90.04 - MJ Electrical (esterification) 31.43 28.93 10.08 - kWh Thermal (transesterification) 1650.84 1733.48 1886.96 2542.95 MJ Electrical (transesterification) 20.34 30.36 28.98 28.47 kWh J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Inventory of input data for the production of 1 t Biodiesel waste rendered rendered dried Transport vegetable beef poultry sewage (by lorry) oils tallow fat sludge To rendering plant 187.76 - - - t km To biodiesel plant 291.31 293.44 292.76 - t km J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Inventory of output data for the production of 1 t Biodiesel waste rendered rendered dried Materials vegetable beef poultry sewage oils tallow fat sludge Biodiesel 1.00 1.00 1.00 1.00 t Glycerol 102.21 115.64 109.00 129.05 kg Salts to landfill 16 9 10 - kg Hazardous liquid waste 30.46 24.00 26.00 - kg Organic waste to landfill 85.40 - - - kg Sludge - - - 2 t J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162
Environmental profile of different transportation diesel fuels J. Dufour and D. Iribarren in Renewable Energy 38 (2012) 155-162