Module 1f. This presentation. Biofuels. Biogas Landfil gas Producergas Bioethanol Biodiesel Pyrolysis oil Solid fuels

Transcription

1 Module 1f Biofuels This presentation Biogas Landfil gas Producergas Bioethanol Biodiesel Pyrolysis oil Solid fuels slide 2/24 1

2 Biogas Component ORC, steam, Stirling motoren Microturbines (Otto en Diesel) (Brayton) H2, CH4, CO Brandstof Brandstof Brandstof H2S <1.000 ppm < ppm <6.000 ppm Water Verwijdering wenselijk Verwijdering wenselijk Verwijdering noodzakelijk Ammoniak < 3 mg/nm 3 < 3 mg/nm 3 < 3 mg/nm 3 Siloxanen Mogelijk schadelijk Verwijdering. Verwijdering noodzakelijk noodzakelijk Halogenen Corrosief Corrosief Corrosief Op druk brengen biogas Nee Nee Ja 60 65% methane de-sulphurisation byproduct (digestate) upgrading to natural gas CO 2 removal slide 3/24 Landfil gas 40 60% methane 20 MJ/m 3 Ban on landfilling Desulphurisation Upgrading to natural gas slide 4/24 2

3 Landfil gas generation Collection and utilisation of gas generated by organic waste in landfills. Can be seen as a natural form of anaerobic digestion. Temperatures, process conditions, gas compositions are similar. Possible applications for the gas: slide 5/24 Flared off (easiest) (CH4 is a stronger greenhouse gas than CO 2 ) Burning in boilers for heat production Electricity production Upgrading to natural gas (most difficult) LFG is a mature technology which is installed on several thousand landfills already Investment costs: USD/kWe Producergas en syngas Different technologies Gas conditioning (tar, dust, cooling) Upgrading to natural gas Small and large scale Syngas (H 2 & CO) converted to methanol slide 6/24 3

4 Liquid biofuels Liquid biofuels are products originating from various plants, which can be used to substitute fossil fuels. Most interesting application is as a transport fuel Types of liquid biofuels Bioethanol Pure Plant Oil (PPO) Biodiesel The technologies for production and use are proven, but at the moment not economical without additional subsidies. slide 7/24 Bioethanol Production process: Fermentation of sugar-containing biomass streams, such as sugar cane and sugar beet, athough all types of biomass are suitable in principle. Process steps are pre-treatment, hydrolysis, fermentation, distillation and dehydration. The production is energy-intensive. Applications: Bio-ethanol is a liquid, which can be mixed with traditional transportation fuels. Engines do not need adaptation, but a minimum of 15% of fossil fuels is still needed. Environmental aspects: The energy input-output ratio is currently 2.4 for cane sugar (2.4 units of energy out for every unit in). Emissions of Greenhouse gases is lower, but NO x emissions are usually higher than with fossil fuels slide 8/24 4

5 Bioethanol Biological Acid / enzymatc hydrolysis + fermentation Thermal Syngas + biological conversion Transport fuel; E20 Sugar (Brazilië), corn (USA) liter per ton biomass slide 9/24 Pure plant oil (PPO) Production process: Pure plant oil from oil-containing plants such as rapeseed, soja and sunflowers) is produced by cold pressing and subsequent filtering. One ha yields 3 tonne of rapeseed, which gives 1 tonne of oil. Costs for production equipment are ca. 70,000 Euro for a 500 kg/hr press. Applications: With some engine modifications, Pure Plant Oil can be used in diesel engines. Engine modifications cost about 5,000 Euro per engine. Environmental aspects: Production is less energy intensive that for bio-ethanol. Combustion in engines causes a significant decrease in emissions of particles (minus 50%), CO (minus 50%) and carbohydrates (minus 20%). Energy inputoutput ratio is reported as maximally 4.1. slide 10/24 5

6 Biodiesel Production process: Esterification of Pure Plant Oil with methanol. The resulting oil has a lower viscosity.from 1 tonne of PPO and 0.1 tonne of methanol, 1 tonne of biodiesel and 0.1 tonne of glycerine is produced. Biodiesel from rapeseed is called RME (Rapeseed Methyl Ester). Also animal fats can be used as feedstock. Applications: Mixing up to 50% with normal diesel is possible without modifications to diesel engines. Environmental aspects: Biodiesel contains hardly any sulfur, correspondingly reducing emissions. Other emissions are also significantly reduced (C x H y, CO and PAC s). Energy input-output ratios in the range of 2.5 up to 3.0. slide 11/24 Biodiesel Extraction PPO + esterification rapeseed, sunflower, jathropa Fischer-Tropsch synthesis Syngas conversion Large scale High acid content Transport fuel; B20 slide 12/24 6

7 Pyrolysis oil Different from bio-oil Slow and fast pyrolysis o C without air High acidity degree Application research slide 13/24 Biodiesel bus slide 14/24 7

8 Plant products platform Selective breeding and genetic engineering Develop plant strains that produce greater amounts of desirable feedstocks or chemicals Even compounds that the plant does not naturally produce Get the biorefining done in the biological plant rather than the industrial plant. slide 15/24 Ethanol yields slide 16/24 8

9 Ethanol production Corn kernels are ground in a hammermill to expose the starch The ground grain is mixed with water, cooked briefly and enzymes are added to convert the starch to sugar using a chemical reaction called hydrolysis. Yeast is added to ferment the sugars to ethanol. The ethanol is separated from the mixture by distillation and the water is removed from the mixture using dehydration slide 17/24 Ethanol production Energy content about 2/3 of gasoline So E10 (10% ethanol, 90% gasoline) will cause your gas mileage to decrease 3-4% Takes energy to create ethanol from starchy sugars Positive net energy balance Energy output/input = 1.67 slide 18/24 9

10 MTBE MTBE (methyl tertiary-butyl ether) A chemical compound that is manufactured by the chemical reaction of methanol and isobutylene Used almost exclusively as fuel additive in gasoline It is one of a group of chemicals commonly known as "oxygenates" because they raise the oxygen content of gasoline At room temperature, MTBE is a volatile, flammable and colorless liquid that dissolves rather easily in water slide 19/24 MTBE Oxygen helps gasoline burn more completely, reducing tailpipe emissions from motor vehicles Oxygen dilutes or displaces gasoline components such as aromatics (e.g., benzene) and sulfur Oxygen optimizes the oxidation during combustion Most refiners have chosen to use MTBE over other oxygenates primarily for its blending characteristics and for economic reasons slide 20/24 10

11 Biofuels First-generation fuels refer to bioenergys made from sugar, starch, vegetable oil, or animal fats using conventional technologies. these biofuels themselves are CO2-neutral when burnt, but their lifecycle (seeding, farming, harvesting, conversion, and agrochemicals and fossil fuels needed to operate bioenergy cropping systems) are the cause of GHG emissions. Second-generation fuels are made from lignocellulosic biomass feedstock using advanced technical processes. slide 21/24 2nd generation biofuels from lignocellulose Advantages compared to 1st generation biofuels: Cheaper feedstock Lower costs of biofuels Lower GHG emissions No competition with food production Higher yields per hectare Wider range of biomass feedstocks slide 22/24 11

12 The biorefinery concept Instead of crude oil, biomass is upgraded and refined to produce a variety of fuels and materials The concept of a biorefinery aims to optimize the conversion of biomass feedstock so that its output mix reflects the highest revenues, and covers all attractive markets. The overall concept is shown in the following figure: Diesel, gasoline Bioethanol, Biodiesel, Biogas, Hydrogen Crude oil Refinery Biomass Biorefinery Basic and Fine chemicals, Polymers Basic and Fine chemicals, biopolymers slide 23/24 Promoting biofuels Why not import ethanol from Brazil? The U.S. imposes a $22/barrel import tariff on Brazilian ethanol So, are the ethanol subsidies in the US just a payoff to the agricultural lobby? Or, are we attempting to build a domestic ethanol industry by subsidizing its early efforts? How best to promote bioenergy? slide 24/24 12

13 THANKS FOR YOUR ATTENTION TERIMAH KASIH 13