Presentation on theme: "Future and energy BIOENERGY What about me 40 years later ? Dr. Bajnóczy Gábor Tonkó Csilla BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICS DEPARTMENT OF."— Presentation transcript:
Future and energy BIOENERGY What about me 40 years later ? Dr. Bajnóczy Gábor Tonkó Csilla BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICS DEPARTMENT OF CHEMICAL AND ENVIRONMENTAL PROCESS ENGINEERING FACULTY OF CHEMICAL AND BIOCHEMICAL ENGINEERING
The pictures and drawings of this presentation are used and can be used only for education ! Any commercial use is prohibited !
Perhaps this will be my car ?
Or these vehicles ?
Fuel shortage ! Is it me at home in winter ?
Or she is my wife waiting for me at home
Energy from bio-energy plant Adequate technology is applied to convert the biomass to - energy (direct conversion) ● combustion - fuel (indirect conversion) ● thermal gasification ● bio-oil by pyrolysis ● gasification by biomethods ● bioethanol production ● biodiesel production
The most important questions are the - ENERGY CONTENT OF THE BIOMASS - Availability of Biomass - Costs
REACTANTS fuel + oxygen T=298 K P= 1 bar PRODUCTS CO 2, SO 2, H 2 O T= 298 K P= 1 bar + HEAT (LHV) PRODUCTS CO 2, SO 2, H 2 O T= 298 K P= 1 bar + HEAT (HHV) liquid complete combustion complete combustion ENERGY CONTENT OF BIOMASS Unit: solid, liquid fuels kJ/kg, MJ/kg gas fuels: kJ/Ndm 3, MJ/ Nm 3 N refers to normal state (0°C ≈ 273,15 K and 1 atm = MPa) Low heat value (LHV) and high heat value (HHV)
LHV and HHV of fuels Measuring by calorimeter Calculation by C% (H% - 1/8 O 2 %) S% HHV = [kJ/kg] (9H% + water%) LHV = HHV [kJ/kg] 100 available hydrogen not typical in biomass
LHV values of fuels Natural gas CH 4 48 MJ/kg the highest hydrogen content Liquid gas CH 3 -CH 2 -CH 2 -CH 3 46 MJ/kg less hydrogen content Oil CH 3 -CH 2 -….-CH 2 -CH 3 42 MJ/kg even less hydrogen content Coal MJ/kg oxygen, water is present Coke mainly carbon 28 MJ/kg lack of hydrogen ! Wood, straw MJ/kg high oxygen content and water Biodiesel CH 3 -(CH 2 ) n -C-OH 38 MJ/kg even less hydrogen content O II Bioethanol CH 3 -CH 2 -OH 27 MJ/kg increased oxygen content Biogas CH 4 : CO 2 ≈50-50% ≈24 MJ/kg CO 2 does not burn
Direct Thermal Conversion of Biomass Combustion
Wood for biomass combustion firewood wood chips Wood pellets The prime cost is significant Energy input: - decreased water content - grinding to powder - high pressure must be applied
BIOMASS CONVERSION TO ENERGY COMBUSTION ON MOVING GRATES
BIOMASS CONVERSION TO ENERGY Combustion in Fluidized Bed Combustion (FBC) boiler The air stream through the grate is strong enough to keep fluid or bubbling state the wood particles Primary air (under fire air) Secondary air (over fire air) The fuel must be uniform in size !
BIOMASS CONVERSION TO ENERGY COMBUSTION III. GILLES pellet heater Household: 10 – 160 kW Industrial: 140 kW – 5 MW The pellet heating is getting more and more popular in western countries
What can we do at home ? ( η = efficiency) Open fire place η= 10 – 15 % Closed fire place η = % Tile stove only for wood η = 60 – 70 % Tile stove for wood and coal η = 60 – 70 % Central heating by pellet η ≈ 90 %
Biomass transformation to fuel Thermal gasification
THERMAL GASIFICATION OF BIOMASS Conversion of biomass into carbon- and hydrogen-rich fuel gases (carbon monoxide, hydrogen, methane) better utilization efficiency of energy conversion ≈ 90 %less environmental polluting materials Fuel gas perfect combustion due to perfect mixing of fuel gas and air due to perfect mixing of fuel gas and air less carbon monoxide, hydrocarbons and shoot particles will be formed.
THERMAL GASIFICATION OF BIOMASS CH 1.4 O 0,6 + O 2 → CO 2 + H 2 O C + CO 2 → CO CH 1.4 O 0,6 → CO + C + (CH) x + H 2 O C + H 2 O → CO + H 2 CO + H 2 O → CO 2 + H 2 Downdraft gasifier 1450 °C °C °C > 200 °C °C Wood (12-20w% moisture) CO v% H v% CO v% CH v% N v% LHV : 5-5,86 MJ/Nm 3 GASIFIER atmospheric CO + 3 H 2 CH 4 + H 2 O 2 C + 2 H 2 CH 4 Syngas or producer gas The methan concentration can be increased by pressure increase
THERMAL GASIFICATION OF BIOMASS in circulating fluidized (CFB) boiler Environtherm.de
THERMAL GASIFICATION OF BIOMASS Direct heat system Synthesis gas for methanol, ethanol production Synthesis gas for Fischer-Troops plant petrol diesel oil lubricating oil Condensation ▼ Bio-oil Direct heat system
GASIFICATION BY BIOMETHODS BIOGAS Produced by biological breakdown of wet organic matters - biomass - manure - sewage - municipal waste - green waste - energy crops in the absence of oxygen (anaerobic digestion) PRODUCT COMBUSTIBLE BIOGAS ~ MJ/Nm 3 Natural gas 32 MJ/Nm 3
LANDFILL GAS flaring heating Jenbacher gasmotor Electric energy Greenhouse effect: CH 4 >> CO 2 The landfill gas is a very polluted gas !! Mercury, chlorinated hydrocarbons, non methane organic compounds Nm 3 / ton. year from the second year
Energy from biomass Maize corn bioethanol → motor fuel
BIOPLANTS FOR LIQUID BIOFUELS BIOETHANOL Photosynthesis of glucose: 6 CO H 2 O + light = C 6 H 12 O O 2 Fermentation by yeast: C 6 H 12 O 6 = 2 C 2 H 6 O + 2 CO 2 + heat Combustion of ethanol: 2 C 2 H 6 O + 6 O 2 = 4 CO H 2 O + heat The carbon dioxide balance is zero → No greenhouse effect
BIOPLANTS FOR LIQUID BIOFUELS BIOETHANOL Row materials: - sugar containing biomass (sugarcane, sugar beet) ● direct fermentation - starch containing biomass (maize, wheat, potato) ● hydrolysis ● fermentation - cellulose containing biomass (wood) ☻long chain cellulose (40-60%) is resistant to hydrolysis ☻ hemi cellulose (20-40%): easy to hydrolyze but the five ring sugars can not be fermented ☻lignin: it is not sugar (10-24%)
BIOPLANTS FOR LIQUID BIOFUELS BIOETHANOL TECHNOLOGY 1. Hydrolysis in case of starch containing row materials 2. Fermentation of glucose - significant water claim, strict pH and temperature control, - additives for the yeast wellness 3. Ethanol separation by distillation - significant energy claim 4. Dewatering of ethanol, by molecular sieves 5. Biofuel mixing - E100 pure ethanol - E90 90v% ethanol 10 v% petrol
BIOPLANTS FOR LIQUID BIOFUELS BIOETHANOL Which is the best row material ? 1. Sugar beet 7140 dm 3 / hectare 2. Sugar-cane 6620 dm 3 / hectare 3. Cassava 4100 dm 3 / hectare 4. Maize corn 3540 dm 3 / hectare 5. Wheat 2770 dm 3 / hectare Sugar beet Sugar cane cassava Maize corn wheat 1 hectare = m 2
No contribution to the greenhouse effect. The carbon dioxide balance is neutral. No sulfur dioxide emission Decrease in carbon monoxide CO, hydrocarbon (CH)x, soot emission due to the oxygen content of bioethanol. No need to change the distribution system. Octane numbers: RON: 121 MON: 97 real RON : Well known technology can be applied Miscibility with petrol BIOPLANTS FOR LIQUID BIOFUELS BIOETHANOL ADVANTAGES
Lower energy content petrol: 43,5 MJ/kg ethanol: 26,8 MJ/kg Starting problems in winter (max: E75) Danger of corrosion Week electrolyte itself Water and acetic acid formation during storage (electrochemical corrosion) Peroxy acetic acid formation inside the chamber (chemical corrosion of metal alloy) Immiscibility with lubricating oil. New environmental pollutants (aldehyde and acetic acid) The row material might be food. (rival in food supply) The energy balance is not outspokenly positive (debates) BIOPLANTS FOR LIQUID BIOFUELS BIOETHANOL DRAWBACKS
Energy from biomass raperape from rape seed Biodiesel from rape → motor fuel Rape-straw, rape-cake: burning → by-products: energy sources
BIOPLANTS FOR LIQUID BIOFUELS BIODIESEL
BIOPLANTS FOR LIQUID BIOFUELS BIODIESEL Row material: - plant product containing any vegetable oil - animal fat (ONLY IN WASTE FORM !) - waste vegetable oil TECHNOLOGY 1.Pretreatment of oil seeds 2. Oil gain by pressing → oil and oilcake 3. Rest oil extraction by organic solvents 4. Transesterification 5. Separation of methylester 6. Purification
BIOPLANTS FOR LIQUID BIOFUELS BIODIESEL Which is the best row material ? palm oil tree : dm 3 /hectare coco palm: 2300 dm 3 /hectare yathropa : 1900 dm 3 /hectare soya : dm 3 /hectare rape seed: 1000 dm 3 /hectare hazelnut: 900 dm 3 /hectare sunflower: 820 dm 3 /hectare algae: 2700 dm 3 /hectare
Row materials for biodiesel Oil palm yathrophaalgae farm
No contribution to the greenhouse effect. The carbon dioxide balance is neutral. The energy content is 9 % less than that of biodiesel. Higher cetane number. Due to the oxygen content less CO and (CH)x. Debates on soot emission. Sulfur content is low. biodiesel : < 0,01mass% diesel : 0,2 mass% Biodegradable Miscibility with diesel oil Excellent lubricating effect. Smaller power loss on roads at higher altitudes from see level (the fuel contains oxygen) BIOPLANTS FOR LIQUID BIOFUELS BIODIESEL ADVANTAGES
The row material might be food. (rival in food supply) The energy balance is not outspokenly positive (debates) The exhaust gas has a definite oily smell. Bacterial attack. BIOPLANTS FOR LIQUID BIOFUELS BIODIESEL DRAWBACKS
IS THE BIOMASS A REAL ENERGY SOURCE ? Let see Hungary ! km 2
Let’s substitute the petrol consumption by bioethanol ! Petrol consumption = ton/year petrol: 43,5 MJ/kg ethanol: 26,8 MJ/kg Maize 2,8 ton alcohol/hectare/year Alcohol claim : * 43.5/26.8 ≈ ton/year Area claim: /2,8 ≈ hectare = km 2 The growing can not be repeated on the same site : Area claim ≈ 3 * = km 2
Let’s substitute the diesel oil consumption by biodiesel ! Diesel oil consumption = ton/year Biodiesel claim : * 1,1 = ton/year Rape: 1000 dm3 biodiesel /hectare/year ≈ 880 kg/hectare/year = 0,88 ton/hectare/year Area claim : /0,88 = hectare = km 2 The growing can not be repeated on the same site : Area claim ≈ 3 * = km 2
Bioethanol vs. Biodiesel II. Wheat bioethanol Maize bioethanol Sunflower biodiesel Rape biodiesel Energy grass only combustion Energy rate1,191,422,352,134,95 The rate of energy output and energy input By Monica Gottfried 2006 thesis
Energy distribution in the future
Conclusions The biomass is only one possibility to reduce the consumption of fossil fuels and decrease the greenhouse effect carbon dioxide emission. From the point of ‘sustainable development’, the total substitution is impossible. From the point of ‘sustainable survival’, it has an outstanding significance.