1. Future and energy BIOENERGY
BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICS
FACULTY OF CHEMICAL AND BIOCHEMICAL ENGINEERING
DEPARTMENT OF CHEMICAL AND
ENVIRONMENTAL PROCESS ENGINEERING
Future and energy BIOENERGY
What about me 40 years later ?
Dr. Bajnóczy Gábor
Tonkó Csilla 1

2. The pictures and drawings of this presentation are used and can be used only for education ! Any commercial use is prohibited !

3. Perhaps this will be my car ?

4. Or these vehicles ?

5. Fuel shortage ! Is it me at home in winter ?

6. Or she is my wife waiting for me at home

7. 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

8. The most important questions are the - ENERGY CONTENT OF THE BIOMASS - Availability of Biomass - Costs

9. ENERGY CONTENT OF BIOMASS
Unit:
solid, liquid fuels kJ/kg, MJ/kg
gas fuels: kJ/Ndm3, MJ/ Nm3
N refers to normal state (0°C ≈ 273,15 K and 1 atm = MPa)
Low heat value (LHV) and high heat value (HHV)
complete
combustion
PRODUCTS
CO2, SO2, H2O
T= 298 K
P= 1 bar
+ HEAT (LHV)
REACTANTS
fuel + oxygen
T=298 K
P= 1 bar
PRODUCTS
CO2, SO2,H2O
T= 298 K
P= 1 bar
+ HEAT (HHV)
liquid
complete
combustion

10. LHV and HHV of fuels Measuring by calorimeter Calculation by
not typical in biomass
available hydrogen
33829 C% (H% - 1/8 O2%) S%
HHV = [kJ/kg]
100
2500 (9H% + water%)
LHV = HHV [kJ/kg]
100

11. LHV values of fuels
Natural gas CH MJ/kg the highest hydrogen content
Liquid gas CH3-CH2-CH2-CH MJ/kg less hydrogen content
Oil CH3-CH2-….-CH2-CH MJ/kg even less hydrogen content
Biodiesel CH3-(CH2)n-C-OH MJ/kg even less hydrogen content O II
Coal MJ/kg oxygen, water is present
Coke mainly carbon MJ/kg lack of hydrogen !
Biogas CH4 : CO2 ≈50-50% ≈24 MJ/kg CO2 does not burn
Bioethanol CH3-CH2-OH MJ/kg increased oxygen content
Wood, straw MJ/kg high oxygen content and water

12. Direct Thermal Conversion of Biomass Combustion

13. Some row materials for biomass combustion
Forestry product
Agriculture product
Agriculture residue
wood
wheat
Straw
branch
maize
oilcake
bark
rape seed

14. 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

15. BIOMASS CONVERSION TO ENERGY COMBUSTION ON MOVING GRATES

16. 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
Secondary air (over fire air)
Primary air (under fire air)
The fuel must be uniform in size !

17. 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

18. What can we do at home ? (η = efficiency)
Tile stove only for wood η = 60 – 70 %
Open fire place η= 10 – 15 %
Tile stove for wood and coal η = 60 – 70 %
Central heating by pellet η ≈ 90 %
Closed fire place η = %

19. Biomass transformation to fuel Thermal gasification

20. THERMAL GASIFICATION OF BIOMASS
Conversion of biomass into carbon- and hydrogen-rich fuel gases
(carbon monoxide, hydrogen, methane)
Fuel gas
better utilization
efficiency of energy conversion ≈ 90 %
less environmental polluting materials
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.

21. The methan concentration can be increased
THERMAL GASIFICATION OF BIOMASS
GASIFIER
Downdraft gasifier
atmospheric
Syngas or producer gas
Wood (12-20w% moisture)
CH1.4O0,6 → CO + C + (CH)x + H2O
CO v%
H v%
CO v%
CH4 2-3 v%
N v% °C
C + CO2 → CO
C + H2O → CO + H2
LHV : 5-5,86 MJ/Nm3
> 200 °C
CO + H2O → CO2 + H2 °C °C
CH1.4O0,6 + O2 → CO2 + H2O
1450 °C
The methan concentration can be increased
by pressure increase
CO + 3 H2  CH4 + H2O
2 C + 2 H2  CH4

22. THERMAL GASIFICATION OF BIOMASS in circulating fluidized (CFB) boiler
Environtherm.de

23. Synthesis gas for Fischer-Troops plant
THERMAL GASIFICATION OF BIOMASS
Direct heat system
Synthesis gas for methanol, ethanol production
Condensation ▼
Bio-oil
Direct heat system
Synthesis gas for Fischer-Troops plant
petrol
diesel oil
lubricating oil

24. 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/Nm3
Natural gas MJ/Nm3

25. Technology of biogas production

26. ENERGY FROM BIOGAS * Methane content 50 v% ** 16 MJ/kg *** 40 MJ/kg
row material
Biogas yield
[Nm3/t]
Energy* content
[kJ]
Wood eq.**
[kg]
Oil eq.***
cattle, pig manure 60
1080 77 27
fresh grass
500
9000
643
225
fat
1300
23400
1671
585
fat grease trap
250
4500
321
113
slaughterhouse waste
300
5400
386
135
techn. glycerin
brewer grains
180
3240
231 81
grain
560
10080
720
252
ENERGY FROM BIOGAS
* Methane content 50 v% ** 16 MJ/kg *** 40 MJ/kg

27. Mercury, chlorinated hydrocarbons, non methane organic compounds
LANDFILL GAS
15-30 Nm3 / ton. year from the second year
flaring
heating
Electric energy
Greenhouse effect: CH4 >> CO2
The landfill gas is a very polluted gas !!
Mercury, chlorinated hydrocarbons, non methane organic compounds
Jenbacher gasmotor

28. bioethanol → motor fuel
Energy from biomass
bioethanol → motor fuel
Maize corn 28

29. BIOPLANTS FOR LIQUID BIOFUELS
BIOETHANOL
Photosynthesis of glucose:
6 CO2 + 6 H2O + light = C6H12O6 + 6 O2
Fermentation by yeast:
C6H12O6 = 2 C2H6O + 2 CO2 + heat
Combustion of ethanol:
2 C2H6O + 6 O2 = 4 CO2 + 6 H2O + heat
The carbon dioxide balance is zero → No greenhouse effect

30. 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%)

31. 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
- E v% ethanol 10 v% petrol

32. BIOPLANTS FOR LIQUID BIOFUELS Which is the best row material ?
BIOETHANOL
Which is the best row material ?
1. Sugar beet 7140 dm3/ hectare
2. Sugar-cane 6620 dm3/ hectare
3. Cassava dm3 / hectare
4. Maize corn dm3/ hectare
5. Wheat dm3/ hectare
Sugar beet
Maize corn
Sugar cane
1 hectare = m2
wheat
cassava

33. BIOPLANTS FOR LIQUID BIOFUELS
BIOETHANOL
ADVANTAGES
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: MON: 97
real RON :
Well known technology can be applied
Miscibility with petrol

34. BIOPLANTS FOR LIQUID BIOFUELS
BIOETHANOL
DRAWBACKS
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)

35. Rape-straw, rape-cake: burning → by-products: energy sources
Energy from biomass
rape
rape from rape seed
Biodiesel from rape → motor fuel
Rape-straw, rape-cake: burning → by-products: energy sources 35

36. BIOPLANTS FOR LIQUID BIOFUELS
BIODIESEL

37. BIOPLANTS FOR LIQUID BIOFUELS
BIODIESEL
Row material:
- plant product containing any vegetable oil
- animal fat (ONLY IN WASTE FORM !)
- waste vegetable oil
TECHNOLOGY
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

38. BIOPLANTS FOR LIQUID BIOFUELS Which is the best row material ?
BIODIESEL
Which is the best row material ?
palm oil tree : dm3/hectare
coco palm: 2300 dm3/hectare
yathropa : 1900 dm3/hectare
soya : dm3/hectare
rape seed: 1000 dm3/hectare
hazelnut: 900 dm3/hectare
sunflower: 820 dm3/hectare
algae: 2700 dm3/hectare

39. Row materials for biodiesel
Oil palm
Oil palm
yathropha
algae farm

40. BIOPLANTS FOR LIQUID BIOFUELS
BIODIESEL
ADVANTAGES
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)

41. BIOPLANTS FOR LIQUID BIOFUELS
BIODIESEL
DRAWBACKS
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.

42. IS THE BIOMASS A REAL ENERGY SOURCE ?
Let see Hungary !
km2

43. Let’s substitute the petrol consumption by bioethanol !
Petrol consumption = ton/year
petrol: 43,5 MJ/kg ethanol: 26,8 MJ/kg
Alcohol claim : * 43.5/26.8 ≈ ton/year
Maize 2,8 ton alcohol/hectare/year
Area claim: /2,8 ≈ hectare = km2
The growing can not be repeated on the same site :
Area claim ≈ 3 * = km2

44. Let’s substitute the diesel oil consumption by biodiesel !
Diesel oil consumption = ton/year
Biodiesel claim : * 1,1 = ton/year
Rape: dm3 biodiesel /hectare/year ≈ 880 kg/hectare/year = 0,88 ton/hectare/year
Area claim : /0,88 = hectare = km2
The growing can not be repeated on the same site :
Area claim ≈ 3 * = km2

45. By Monica Gottfried 2006 thesis
Bioethanol vs. Biodiesel II.
The rate of energy output and energy input
By Monica Gottfried 2006 thesis
Wheat
bioethanol
Maize
Sunflower
biodiesel
Rape
Energy grass
only combustion
Energy rate
1,19
1,42
2,35
2,13
4,95

46. Energy distribution in the future

47. 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.