FEAD Workshop Tallin 14 May 2009

Landfill gas extraction

Gilberto Garuti

ITS® plants

Bergamo, 1998

Spagna - Castellon de la Plana Villafalletto (CN), 2004 Cavaglià (BI), 2003

Corteolona (PV), 1996

Giussago (PV), 1996

Lacchiarella (MI), 2002

Montanaso (LO), 2000

Dumfries & Galloway

Londra - Frog Island

Londra – Jenkins Lane

2

• Il

Technical details of ITS plants

3

Primary Shredder and

Automatic Grabbing Crane System

Biodrying pit

Biofilter and Ventilation System Refinement Section View

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Biodried Material

Mechanical Selection

Under-sieved

Al

Fe

Heavy discarded materials

SF

RECYCLING

Flexibility in the use of products

4

Renewable energy

production

Biogas

Leachate infiltration

Bio

gas

ext

ract

ion

The discarded materials coming from the Secondary Fuel production is where the slowly degradable (methanogenic) fraction is concentrated.

This fraction and/or the biodried material can be exploited energetically speaking by means of an Activatible Bioreactor which assure the following:

• High conversion rate of Degradable Organic Substance into biogas

• Minimisation of the emission during landfilling stage

• Recovery of the Bioreactor volumes through landfill-mining and energy recovery of the residual plastics

ACTIVABLE BIOREACTOR:Energetic exploitation of the Biodried Material

5

Renewable energy

production

Biogas

Leachate infiltration

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Activable Bioreactor

Leachate treatment

Leachate recycle

Bio

gas

ext

ract

ion

Renewable

energy

production

Leachate infiltration

Biogas

250-270 kWh/t

150-200 kg/t

50-75 kg/t

70-85 Nmc CH4/t

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Landfill gas extraction

Leachate removal

Bio

gas

ext

ract

ion

Aerobic infiltration

Flow monitoring

Quality monitoring

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

LFG extraction

• Flow monitoring- Extracting pressure

- Overpressure

- Biogas flow

- Pressure/time test

• Quality monitoring- Methane, Oxigen, CO2 concentration

- CO concentration

- Temperature

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Flow monitoring

• Pressure/time test

26N1

0

10

20

30

40

50

60

70

80

0 50 100 150 200 250 300 350 400

tempo

pre

ssio

ne

High flow well

Low flow well

well 23N0

0

5

10

15

20

25

30

35

0 100 200 300 400 500 600 700 800 900 1000

time [sec]

pre

ssu

re [

mm

w.c

.]

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Flow monitoring and control

Leachate removal

Aerobic infiltration

Extracting pressure

LFG flow

Overpressure

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Quality monitoring

• Methane concentration• Oxigen concentration

• Methane/carbon dioxide ratio

• Temperature

• CO (carbon monoxide) concentration

• H2S and siloxane

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Quality monitoring

• Methane, carbon dioxide and oxigen concentration• Residual nitrogen

Young landfill Old landfill

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Quality monitoring

Methane and carbon dioxide ratio

Carbon dioxide is usually considered the floating variable in the LFG mixture and could reflect the condition of the landfill.

In our bioreactor landfills, CH4/CO2 ratio value:

< 1 beginning of activation, or over-stressed1.0 – 1.1 aggressive extraction1.1 – 1.2 normal desiderable operating range> 1.2 normal to understressed

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Quality monitoring

Landfill gas Temperature

Excessive localized overpull encurages aerobic activity, and this could increase the operating temperature.

Temperature > 60°C indicates aerobic conditions:

LFG flow should be reduced

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Quality monitoring

• Carbon monoxide concentration

Carbon monoxide is a possible intermediate in the metabolic pathway of anaerobic and aerobic bacteria.

Carbon monoxide was found in significant level during activation or starting of the methanogenic production.

High level of carbon monoxide should be viewed with caution as an early indicator of conditions that can lead to landfill fires.

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Quality monitoring related to energy production

• Sulfide• Halogenated compounds• Siloxane

Sulphur compounds are corrosive in the presence of free water or the moisture

found within the engine oil and/or landfill gas

Halogenated compounds containing chlorine, bromine and fluorine (e.g. carbon

tetrachloride, chlorobenzene, chloroform and trifluoromethane) are broken

down during the combustion process and can form the acid gases, HCl and HF,

in the presence of moisture. These are responsible for corrosion of metal piping

and engine components.

Organosiloxanes are semi-volatile organosilicon componds which, while not an

aggressive gas component in terms of emissions, can be converted to solid

inorganic siliceous deposits within the engine combustion chamber

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Analysis of biogas compounds by FT-IR instrument

Smart Interferometer

Smart Detector

HeNe Laser

Snap-In™ Baseplate

E.S.P. Accessory Readers

Smart Electronics

Ever-Glo SourceDesiccant

External Beam Flip MirrorKBr windows

Diamond turned Optics

Diamond turned Optics

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

0,0

0,5

1,0

1,5

2,0

2,5

3,0

3,5

4,0

4,5

5,0

5,5

6,0A

bs

orb

an

ce

500 1000 1500 2000 2500 3000 3500 4000 Wavenumbers (cm-1)

H 1035

H 818

CO2

CO2

CO2

CO2

CH4

CH4

H

Figure 2

High Quality spectrum of many LFG compounds

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Analysis of the adsorption capacity in a filter

-0,003

-0,002

-0,001

-0,000

0,001

0,002

0,003

0,004

0,005

0,006

0,007

0,008

0,009

Absorbance

800 850 900 950 1000 1050 1100 1150

Wavenumbers (cm-1)

1089 cm-1: D4

815 cm-1: D4

1057 e 1033 cm-1: CH3OH

IN

OUT

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

0

0,2

0,4

0,6

0,8

1

1,2

1,4

1,6

1,8

0 50 100 150 200 250t/min

Ab

so

rba

nc

e

fresh

Spent half column

Spent end column

Initial value

Analysis of activated carbon residual capacity

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent.

Analysis of all biogas component

With FT-IR instrument we are developing a procedure to analise many biogas component before and after the gas cleaning system

In the future we plan to extend the same procedure to the exhausted gas from the energy production systems

With the analysis of some biogas components is it possible to know better the process and/or degradation phase of the refuse ??

ufficio.tecnico@ecodeco.it

This information was prepared by A2A and it is not to be relied on by any 3rd party without A2A’s prior written consent. 22

Ecodeco headquarters