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LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila – Facoltà di Ingegneria Dipartimento di Chimica, Ingegneria Chimica e Materiali http://www.ing.univaq.it/ http://www.uniqueproject.eu/ telefono: +39 0862 702050 Pescara, 23 Febbraio 2010

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Page 1: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

LE BIOMASSE

UNA FONTE SOSTENIBILE DI ENERGIA

Pier Ugo FOSCOLO

PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE

Università dell’Aquila – Facoltà di Ingegneria

Dipartimento di Chimica, Ingegneria Chimica e Materiali

http://www.ing.univaq.it/ http://www.uniqueproject.eu/

telefono: +39 0862 702050

Pescara, 23 Febbraio 2010

Page 2: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Biomass gasification and fluid-dynamics of fluidized bed reactors are actively cultivated in the

CRE laboratory at UNIVAQ since more than 25 years, at the level of theoretical and

experimental research investigations, including industrial contracts.

Research Group

Prof. Pier Ugo Foscolo, full professor in Chemical Reaction Engineering;

Prof. Larry Gibilaro, previously employed (as full professor) at University College

London;

Prof. Antonio Germanà, part-time professor of Chemical and Process Plant Design;

Dr Ing. Katia Gallucci, assistant professor in Chemical Engineering;

Post doctoral researchers, PhD students and technical staff

CIRBE – Centro Interuniversitario di Ricerca sulle Biomasse a scopi Energetici

In collaboration with the University of Teramo – Faculty of Agriculture

Prof. Sergio Rapagnà

Page 3: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Greatest challenges of sustainability:

• number one energy

• number two clean drinking water

Source: Nobel Chemist Richard Smalley

“Carbon derived from biomass and then returned to the atmosphere does not add to the

accumulation of carbon in the atmosphere, but rather just closes the carbon cycle”

Collective implementation of sustainable solutions:

• increased energy efficiency in transportation, electricity production and buildings;

• use of biofuels and renewable resources;

• carbon sequestration

Source: Pacala and Socolow, Science, 2004

Page 4: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

B

I

O

M

A

S

S

• an abundant and distributed source of energy and chemicals,

resulting from storage of solar energy on the earth;

• the biomass production – power generation cycle is characterized

by near-zero contribution to the accumulation of green-house gases

(sustainable growth);

• the renewable source with the highest potential to contribute to

the energy needs of modern society for both the developed and

developing economies world-wide.

A FAIRLY DIFFERENT PERSPECTIVE IN RELATION TO FOSSIL ENERGY

SOURCES!

FOR A GLOBAL AND WIDESPREAD BREAKTHROUGH OF

RENEWABLES (AND BIOMASS AMONG THESE) DIFFERENT

SCENARIOS IN THE WORLD ECONOMY NEED TO BE ESTABLISHED

IS THIS A REMOTE HYPOTHESIS?

Page 5: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila
Page 6: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Physical and chemical properties of biomass (example)

Type Almond shells

Status Raw Dry Dry-ash-free (daf)

Moisture (wt%) 7.90 - -

Ash (wt%) 1.16 1.26 -

Volatile matter (wt%) 72.45 78.66 79.67

Carbon (wt%) 46.65 50.65 51.30

Hydrogen (wt%) 5.55 6.03 6.10

Oxygen (wt%) 38.74 42.06 42.60

LHV (kJ/kg) 18350

Cellulose (wt%) 29

Hemicellulose (wt%) 28

Lignin (wt%) 35

Density (kg/m3) 1200

Page 7: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Physical and chemical properties of biomass (example)

Type Dry oak wood (without bark)

Status Raw Dry-ash-free (daf)

Moisture (wt%) 5.2

Ash (wt%) 0.6

Volatile matter (wt%) 82.4

Fixed carbon 11.8

(proximate analysis)

Carbon (wt%) 51.8

Hydrogen (wt%) 6.6

Nitrogen (wt%) 0.3

Oxygen (wt%) 41.3

(elemental analysis)

Page 8: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Physical and chemical properties of biomass (example)

Type Energy crop: Miscanthus X Giganteus

Status Raw Dry

Moisture (wt%) 11.0 -

Ash (wt%) 2.46 2.76

Volatile matter (wt%) 80.0

Carbon (wt%) 43.32 48.67

Hydrogen (wt%) 4.85 5.45

Oxygen (wt%) 37.83 42.5

S 0.036 0.04

Cl 0.20 0.23

N 0.40 0.45

Density (kg/m3) a.r. 150

Density (kg/m3) pellets 600

Page 9: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

B

I

O

R

E

S

I

D

U

E

S

• waste-biomass has the potential to provide as much as 330

GW of electric power world-wide, if utilized efficiently;

• in Mediterranean countries (because of climate), in Eastern

EU countries (because of extensive utilization of land for food

crops), and in intensely populated industrial areas, energy

crops and virgin biomass are scarce, and costly because of

alternative uses;

• when agricultural and forestry wastes, by-products of agro-

industrial processes or MSW (RDF) are utilized as feedstock,

the problem and the cost of disposal are reduced, and this

contributes positively to the economic balance of the

conversion process to energy or chemicals.

AN INTERESTING NICHE MARKET!

Page 10: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Physical and chemical properties of biomass (example)

Type Olive waste from oil production

Status Raw Dry Dry-ash-free (daf)

Moisture (wt%) 8.90 - -

Ash (wt%) 7.74 8.5 -

Volatile matter (wt%) 67.78 74.40 81.31

Carbon (wt%) 43.93 48.22 52.70

Hydrogen (wt%) 6.00 6.59 7.20

Oxygen (wt%) 31.76 34.86 38.10

Nitrogen (wt%) 1.33 1.46 1.60

Sulphur (wt%) 0.05 0.06 0.07

Chlorine 0.34 0.34 0.37

LHV (kJ/kg) 18500

Bulk density (kg/m3) 659

Page 11: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Physical and chemical properties of biomass (example)

Type Rice husk

Status Raw Dry Dry-ash-free (daf)

Moisture (wt%) 6.96 - -

Ash (wt%) 14.71 15.8 -

Volatile matter (wt%) 66.69 71.71 85.17

Carbon (wt%) 36.25 38.96 46.27

Hydrogen (wt%) 4.75 5.11 6.07

Oxygen (wt%) 35.32 37.96 45.08

Nitrogen (wt%) 2.02 2.17 2.58

Sulphur (wt%) 0.13 0.14 0.17

Chlorine - - -

LHV (kJ/kg) 13544 17290

Bulk density (kg/m3) 161

Page 12: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

The figures of the energy issue

According to the International Energy Agency, world energy demand is set to increase by more

than 50% by 2030 (41% for oil demand alone)

Oil and gas reserves are increasingly concentrated in a few countries that control them through

monopoly companies

The dependence of Europe on imported oil and gas is growing: we import 50% of our energy,

and it will be 65% by 2030 if we don’t act

If oil price increases to 100$ per barrel by 2030, the EU annual energy import bill will increase

by more than 350€ for every EU citizen, and none of this would bring additional jobs and wealth

to Europe

The world emissions of CO2 (which accounts for 75% of all greenhouse gases) will increase by

55% by 2030

Page 13: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

EU Renewables Directive 2001/77/EC

• 12% Energy from renewable sources by 2010.

• EU projections – 75% from Biomass.

EC Communication to the European Parliament and

Council (10.01.07)

"An Energy Policy for Europe"

• 20% cut in greenhouse gas emissions by 2020

• See http://europa.eu.int/comm/energy/

Page 14: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Renewable Energy Barometer, 2006

The share of biomass in the renewable primary energy production in EU has been 66% in 2005

In the renewable electricity generation the share of biomass is 16% in 2005, about the same as

that of wind

Primary solid biomass production (not including renewable solid urban waste) is in marked

increase with 5.7% growth in 2005 with respect to the year before (+3.196 Mtoe)

European electricity production of solid biomass origin is also in marked growth, with a 16.2%

increase between 2004 and 2005 (+6.1 TWh, i.e. a total of 44.1 TWh)

Page 15: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

0

0.5 1

1.5 2

2.5 3

3.5 4

4.5

Total E.U. 25

United Kingdom

Germany

Spain

France

Italy

Sweden

Netherlands

Denmark

Portugal

Czech Rep.

Poland

Belgium

Austria

Greece

Ireland

Finland

Slovenia

Luxembourg

Slovakia

Estonia

Hungary

Biogas in Europe Mtoe

20

03

20

04

Eu

rOb

serv

’ER

20

05

–B

iog

as

Ove

rall in

cre

ase E

.U. 2

5 –

9.1

%

Page 16: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Why the Different Developments?

• Availability of different feedstocks.

• Size of farms –

– USA + Brazil very large quantities of biomass from few

producers – easier to scale-up – ethanol.

– EU – smaller farms – small to medium scale CHP –

biodiesel.

• Success stories in biomass use are linked to:

– Tax incentives/guidance from local administrators.

– Availability of waste material from industrial production.

– Optimal use of biomass resource.

Page 17: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Source: Prof. Ni Weidou, Tsinghua University

• Resources - China– Straws and stalks – 300 mil. tce

– Waste of forest

– Special plants in deserts

• Features– Highly scattered

– Collection and transportation will be a big problem

– Reasonable collection radius – less than 5 km

• For 25 MW power plant with biomass-firing, the radius of collection will be more than 100 km (biomass conversion)

• In China and in parts of the developing world distributed, on-site collection, production and utilization may be more appropriate (small-medium scale plants)

1.0 billion tce

ton of coal equivalent (TCE) = 29.3 GJ – www.wikipedia.org

Page 18: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

•Direct combustion or co-firing.

•Gasification – air or steam – to produce syngas.

•Pyrolisis – to produce both liquid and gaseous fuels.

•Cellulose and hemicellulose to basic sugars.

•Biodiesel – ethyl or methyl esters from trans-esterification of vegetable oils.

•Biofuels – produced from syngas.

•Biogas – anaerobic digestion of residues.

•…

BIOMASS CONVERSION

Page 19: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

BIOMASS THERMAL CONVERSION

Source: Prof. A.V. Bridgewater, 2003

Page 20: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Thermally induced biomass decomposition occurs over the temperature range 250 ÷÷÷÷ 500°C,

and the primary pyrolysis (devolatilization) products are

gases, organic vapours, char

Their relative yields depend on heating rate and final temperature.

Combustion:

The product is heat, to be used immediately for heat and/or power generation.

Overall efficiencies to power ≈≈≈≈ 15% for small plants

up to 30% for larger and new plants

Costs are specially competitive when agricultural, forestry and industrial wastes are utilized.

A well established technology, with a large variety of applications, at small and medium scale.

Page 21: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Flash pyrolysis:

high heating rates (small particles < 2 mm)

moderate pyrolysis reaction temperature (T ≈≈≈≈ 500°C)

short vapour residence time (ττττ ≤≤≤≤ 2 s)

fluidized bed, and special design reactors

separation of organic vapours from char particles

(cyclones are better than filters)

rapid cooling of pyrolysis vapours to give raw bio-oil

Bio-oil:

a complex mixture of oxigenated hydrocarbons

(about the same elemental composition of biomass)

yield: up to 75% by weight of the original fuel on dry basis

LHV ≈≈≈≈ 17 MJ/kg (40% of conventional fuel oil diesel)

does not mix with hydrocarbon fuels

upgrading: hydrotreating, catalytic cracking (costly!)

Page 22: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Source: Prof A.V. Bridgewater, 2003

Variation of products with temperature in a flash pyrolysis process

Page 23: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Gasification:

fuel gas (CO, CO2, H2, CH4) is obtained by partial oxidation and steam

or pyrolytic reforming of vapours and char (air/O2/steam gasification)

T ≤≤≤≤ 850°C, to avoid ash sintering phenomena

ττττ > 2 s, to allow enhancement of heterogeneous reactions

fixed and fluidized bed gasification reactors

primary and downstream catalytic treatments improve gas quality

up to 85% by weight of the original dry biomass is converted in gas

LHV: from 4 MJ/Nm3 (air gasification) to 12 MJ/Nm3 (O2/steam

gasification)

hot gas efficiency up to 95% (total energy in raw gas/energy in the feed)

cold gas efficiency up to 80% (raw gas/biomass feedstock heating value)

Page 24: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Gasification:

the closest to industrial exploitation from among the available conversion

options, for efficient power generation and synthesis of commodity

chemicals;

it can be well integrated with MCFC or SOFC (molten carbonate and solid

oxide fuel cells accept syn-gas as a fuel because operate at high

temperature), and FC + turbine or gas turbine + steam turbine combined

cycles for stationary power generation, with net electric efficiencies > 40%

(pressurized gasification);

it is a source of hydrogen: a pure H2 energy vector is obtainable by

combining biomass gasification with a CO2 sorption process (for instance,

with calcined dolomite) for a variety of utilities and applications;

the technologies to obtain chemicals from the producer gas are

commercially available. Major obstacles are: Large scale operation and

High gas quality;

gasification will be able to better penetrate di energy markets if it is

completely integrated into a biomass system.

Page 25: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Utilization of gas from biomass gasification

Source: Prof A.V. Bridgewater, 2003

Page 26: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila
Page 27: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

CHP in Güssing Austria

Page 28: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Schematic flow diagram of the biomass power plant in Guessing (Source: T. Pröll, April

2004)

Page 29: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila
Page 30: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

CHP in Güssing Austria

Start up of gasifier November 2001

Start up of gas

engine

April 2002

Fuel wood chips

Fuel Power 8000 kW

Electrical output 2000 kW

Thermal output 4500 kW

Page 31: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Güssing Austria – Reasons for Success

• 40% of region is covered by forest.

• In early ’90s the Major decided to change the energy supply of the city to local renewable sources.

• District heating now supplies 95% of users

• 2 MW production covers the city’s demand for electricity.

• Biodiesel is produced from a RME plant built in 1990.

Page 32: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Biogas production – landfill

Preparation of site + gas piping installation – MARCA project – Biogas Technology Ltd

Page 33: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Biogas production – landfill

Flaring and LFG electricity generator – MARCA project – Biogas Technology Ltd

1 MWe

2 MWe

35 yrs

Page 34: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Landfill gas composition

Gas to energy projects - California

Composition Range Average

Methane 35-60% 50%

Carbon Dioxide 35-55% 45%

Nitrogen 0-20% 5%

Oxygen 0-2.5% <1%

Hydrogen

Sulfide

0-1700 ppmv 21 ppmv

Halides NA 132 ppmv

Water 1-10% NA

Other organics 237-14500

ppmv

2700 ppmv

Page 35: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Biogas production – digestors

Expanded (fluidized) granular sludge bed – developed by G. Lettinga.

Page 36: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Biogas production – large scale digestors

Twin-stage UASB anaerobic digester for waste and waste water treatment.

Hiriya, Tel Aviv, Israel

UASB reactor

Page 37: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Biogas composition

Yadava, L. S. and P. R. Hesse (1981)FAO/UNDP Regional Project RAS/75/004, Project Field Document No. 10

Composition Range

Methane 50-70%

Carbon Dioxide 30-40%

Hydrogen 5-10%

Nitrogen 1-2%

Water 0.3%

Hydrogen Sulphide Traces

Page 38: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Biogas C/N ratios of feed

Karki and Dixit (1984) - Biogas Fieldbook

Raw material C/N ratio

Duck dung 8

Human excreta 8

Chicken dung 10

Pig dung 18

Sheep dung 19

Cow dung 24

Elephant dung 43

Straw (maize) 60

Straw (rice) 70

Straw (wheat) 90

Saw dust above 200

Page 39: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Biogas inhibitors

The Biogas Technology in China, BRTC, China (1989)

Inhibitor Inhib. conc.

Sulphate (SO4--) 5000 ppm

Sodium Chloride 40000 ppm

Nitrate 0.05 mg/ml

Copper (Cu++) 100 mg/l

Chromium (Cr+++) 200 mg/l

Nickel (Ni+++) 200-500 mg/l

Sodium (Na+) 3500-5500 mg/l

Potassium (K+) 2500-4500 mg/l

Calcium (Ca++) 2500-4500 mg/l

Magnesium (Mg++) 1000-1500 mg/l

Manganese (Mn++) above 1500 mg/l

Page 40: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Small scale biogas – optimal conditions

• Temperature 35 °C.

• Inlet pH 6-7.

• Loading rate varies

– Too high: acids accumulate and cause inhibition

– Too low: not enough nutrients

• Retention time – 50-60 days.

• Mix materials to increase C/N ratio

Page 41: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Ashden Awards for sustainable energy

• Biogas cooking stoves for villages on the fringes of the tiger reserve in Ranthambhore Park

– Prakratik Society: India, 2004.

• Domestic biogas for cooking and sanitation

– Biogas Sector Partnership: Nepal, 2005

• Biogas plants providing sanitation and cooking fuel in Rwanda

– Kigali Institute of Science, Technology and Management (KIST): Rwanda, 2006.

• …

• See http://www.ashdenawards.org/

Page 42: LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA · LE BIOMASSE UNA FONTE SOSTENIBILE DI ENERGIA Pier Ugo FOSCOLO PROFESSORE DI INGEGNERIA DELLE REAZIONI CHIMICHE Università dell’Aquila

Ashden Awards for sustainable energy

India, 2004

Rwanda, 2006

Nepal, 2005