Biofuels Sustainable development Prof. Melania Mu±oz Sustainable development Prof. Melania Mu±oz

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BiofuelsSustainable developmentProf. Melania Muoz

fuels derived frombiomass (organic materials). In order to be considered a biofuel the fuel must contain over 80% renewable materialsThe term coverssolid biomass,liquid fuelsand variousbiogases.

Sustainable development Prof. Melania Muoz G.What is a biofuel?

Biofuels are gaining increased public and scientific attention.

Factors:

Need for increase energy security

Concern over greenhouse gas emission from fossil fuels

Are portable and clean burning

Sustainable development Prof. Melania Muoz G.Biofuels

Biofuels are gaining increased public and scientific attention, driven by factors such asoil price spikes, the need for increasedenergy security, and concern overgreenhouse gasemissions fromfossil fuels.

The fuels that are easiest to burn cleanly are typically liquids and gases. Thus liquids (and gases that can be stored in liquid form) meet the requirements of being both portable and clean burning. Also, liquids and gases can be pumped, which means handling is easily mechanized, and thus less laborious.

3Sustainable development Prof. Melania Muoz G.Bioethanol production

Biofuels are gaining increased public and scientific attention, driven by factors such asoil price spikes, the need for increasedenergy security, and concern overgreenhouse gasemissions fromfossil fuels.

The fuels that are easiest to burn cleanly are typically liquids and gases. Thus liquids (and gases that can be stored in liquid form) meet the requirements of being both portable and clean burning. Also, liquids and gases can be pumped, which means handling is easily mechanized, and thus less laborious.

4Sustainable development Prof. Melania Muoz G.Biodiesel production

Biofuels are gaining increased public and scientific attention, driven by factors such asoil price spikes, the need for increasedenergy security, and concern overgreenhouse gasemissions fromfossil fuels.

The fuels that are easiest to burn cleanly are typically liquids and gases. Thus liquids (and gases that can be stored in liquid form) meet the requirements of being both portable and clean burning. Also, liquids and gases can be pumped, which means handling is easily mechanized, and thus less laborious.

5Made from:SugarStarchVegetable oilAnimal fat

Basic feedstocks:Seeds and grains

Sustainable development Prof. Melania Muoz G.First-generation biofuels

First-generation biofuels' are biofuels made from sugar, starch, vegetable oil or animal fats using conventional technology.

The basic feedstocks for the production of first generation biofuels are often seeds orgrainssuch assunflowerseeds, which are pressed to yield vegetable oil that can be used in biodiesel, orwheat, which yields starch that is fermented into bioethanol.

6Why is it controversial?

Sustainable development Prof. Melania Muoz G.First-generation biofuels

These feedstocks could instead enter the animal or human food chain, and as the global population has risen their use in producing biofuels has been criticised for diverting food away from the human food chain, leading to food shortages and price rises.

7The use of this feedstocksin producing biofuels has been criticised for diverting food away from the human food chain, leading to food shortages and price rises

Sustainable development Prof. Melania Muoz G.First-generation biofuels

These feedstocks could instead enter the animal or human food chain, and as the global population has risen their use in producing biofuels has been criticised for diverting food away from the human food chain, leading to food shortages and price rises.

8Major feedstockSustainable development Prof. Melania Muoz G.

Produced by the action ofmicroorganisms andenzymesthrough the fermentation of sugars or starches

Sugars are obtained fromwheat,corn,sugar beets,sugar cane

Most common: ethanolAlso: propanol and butanol

Sustainable development Prof. Melania Muoz G.First-generation biofuels

BioalcoholsBiologically producedalcohols, most commonlyethanol, and less commonlypropanoland butanol, are produced by the action ofmicroorganisms andenzymesthrough the fermentation of sugars or starches (easiest), or cellulose (which is more difficult).

Biobutanol (also called biogasoline) is often claimed to provide a direct replacement for gasoline, because it can be used directly in a gasoline engine (in a similar way to biodiesel in diesel engines).

10Sustainable development Prof. Melania Muoz G.

bagasse_ /bigeas/

Hydrated /jaidreited/11Sustainable development 2012 Prof. Melania Muoz G.Taboga

bagasse_ /bigeas/

Molasse /moelses12Edible oil is generally not used as a fuelLower quality oil is usedIt is processed into biodiesel or (more rarely) used directly as a fuelSustainable development Prof. Melania Muoz G.First-generation biofuelsVegetable oil

Biodiesel is typically made by a chemical reaction(transesterification) : lipids + alcohol = fatty acid esters(e.g.,vegetable oil, animal fat)

Biodiesel

Straight unmodifiedediblevegetable oil is generally not used as fuel, but lower quality oil can be used for this purpose. Used vegetable oil is increasingly being processed into biodiesel, or (more rarely) cleaned of water and particulates and used as a fuel. 13Feedstock:Oils: e.g. canola, algae, jatropha and salicornia

Use traditional fractional distillation to process the oils

Do not confuse it with biodiesel (chemical reaction)First-generation biofuelsGreen diesel

Green diesel, also known asrenewablediesel, is a form of diesel fuel which is derived from renewable feedstock rather than the fossil feedstock used in mostdiesel fuels. Green diesel feedstock can be sourced from a varietyoils includingcanola,algae, jatrophaand salicorniain addition totallow. Green diesel uses traditionalfractional distillationto process the oils, not to be confused with biodiesel which is chemically quite different and processed using transesterification.

14It ismethaneproduced by the process ofanaerobic digestionoforganic material:biodegradable wastematerialsenergy cropsfeed anaerobic digesters

The solid (or liquid) byproduct,digestate, can be used as a fertilizer

Farmers can produce biogas frommanurefrom their cows by getting a anaerobic digester (AD)

Sustainable development Prof. Melania Muoz G.First-generation biofuels

Biogas/Daijesteit/Biogas ismethaneproduced by the process ofanaerobic digestionoforganic materialbyanaerobes .

It can be produced either frombiodegradable wastematerials or by the use ofenergy cropsfed into anaerobic digestersto supplement gas yields. The solid byproduct,digestate, can be used as a biofuel or a fertilizer.

Biogas can be recovered frommechanical biological treatmentwaste processing systems.

Farmers can produce biogas frommanurefrom their cows by getting a anaerobic digester (AD)

15Sustainable development 2012 Prof. Melania Muoz G.First-generation biofuels

BiogasOrganic fertilizerGas. E.g. kitchenTurbine and generator:electricity/Vlatl/16Examples:WoodSawdustgrasstrimmingsdomestic refuseCharcoalagricultural wastenon-foodenergy cropsdrymanure.

When raw biomass is already in a suitable form (such asfirewood), it can burn directly in a stove or furnace to provide heat or raise steam

Sustainable development Prof. Melania Muoz G.First-generation biofuels

Solid biofuel

Examples includewood,sawdust,grasstrimmings,domestic refuse,charcoal,agricultural waste, non-foodenergy crops, and driedmanure.When raw biomass is already in a suitable form (such asfirewood), it can burn directly in a stove or furnace to provide heat or raise steam. When raw biomass is in an inconvenient form (such as sawdust, wood chips, grass, urban waste wood, agricultural residues), the typical process is