-clean energy supplyclean energy supplyfor a sustainable societyfor a sustainable society

Lina Vallin David Kvick

Jörgen EjlertssonAnna Karlsson

Production site in Linköping

• Production started in 1997.

• 54 000 tones of organic materials processedannually.

• 50 000 tones of certified biofertilizer soldannually on a regional market.

Total sales of 4,5 million Nm3 biogas (97 % CH4)

The biogas process

Substrates treated at the plant

Product Amount Share of total amount

  tons (%)

Slaughtery industry 28 300 75%

Food industry 5 800 15%

Pharmaceutical industry 600 2%

Alcohol 1 200 3%

Manure 2 000 5%

Biofertilizer

Provides routines for the production plant in respect to get a valuable and stable biofertilizer.

Insurance of quality for the farmer.

Confidence in the product for the customers to the farmer e.g. food processing industries.

Biogas in Sweden• EU’s goal for 2020 means every fifth car.

• Great focus on market expansion with a

common goal of 100 filling stations before

2010 (34 st 2003 ~50 st 2004)

• Svensk Biogas filling stations 2005/2006

(13 in total):

• Linköping (4)• Norrköping (1+1)• Katrineholm• Nyköping• Mjölby• Örebro• Västervik (+1)• Motala (+1)

Progress of the productionProgress of the production

Gas production today: 155 Nm3/ton substrate

0

1 000 000

2 000 000

3 000 000

4 000 000

5 000 000

6 000 000

7 000 000T

ota

l b

iog

as

pro

du

cti

on

(N

m3

)

1997 1998 1999 2000 2001 2002 2003 2004

Process development

• Increased knowledge of the microbiological process in the digester

• Optimization of the process at the current production plant in Linköping

• New concepts for biogas production

Lab scale reactors

Mesophilic digestion, 37 degrees

Volume 3 L

Volumetric gas meters

Analysis of: • substrates• process parameters• biofertilizer

Lab scale experiments

• Addition of iron chloride and hydrochloric acid

• Experimental plan: – Controls (1a & 2a) – Post-digestion of the control reactors (retention time 12.5 days)– Reactors (3 & 4) with adjusting of pH (7.5 respectively 7.8)

• Substrate: from the full scale plant.

Results – gas production

0

2

4

6

8

10

12

14

16

-3 0 3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 51 54 57 60 63 66 69

Day

Pro

du

cti

on

of

bio

ga

s (

L/(

da

y a

nd

4L

rea

cto

r))

♦ 1a normal ■ 1b post-digestion normal ▲ 2a normal● 2b post-digestion pH 7.5 x 3 pH 7.5 + 4 pH 7.8

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

-6 -2 2 6 10 14 18 22 26 30 34 38 42 46 50 54 58 62 66

Day

Ace

tate

(m

g/l

)Results – acid production

♦ 1a normal ■ 1b post-digestion normal ▲ 2a normal● 2b post-digestion pH 7.5 x 3 pH 7.5 + 4 pH 7.8

Amount of organic acids at the Linköping biogas plant

0

2500

5000

7500

10000

12500

15000

17500

20000

22500

25000

27500

30000

3250019

99-0

6-19

1999

-07-

09

1999

-07-

29

1999

-08-

18

1999

-09-

07

1999

-09-

27

1999

-10-

17

1999

-11-

06

1999

-11-

26

1999

-12-

16

2000

-01-

05

2000

-01-

25

2000

-02-

14

2000

-03-

05

2000

-03-

25

2000

-04-

14

2000

-05-

04

2000

-05-

24

2000

-06-

13

2000

-07-

03

Co

nc

en

tra

tio

n o

f o

rga

nic

ac

ids

(m

g a

ce

tate

/L)

Rk1(mg/l)

Rk2(mg/l)

Conclusions

• The experiment resulted in an increase of 30 % gas production when pH was adjusted to 7.5 and 7.8.

• The amount of organic acids were decreased by 50 %, which indicates a stabilization of the process.

• The product was implemented at the plant in Linköping with good results.

• The composition of the product and the amount added must be optimized in regard to the substrate fermented.

• The product has been developed in cooperation with Kemira, and will soon be available on the market.

• The product has been patented by Tekniska Verken i Linköping AB (publ.).

For further information:

Lina Vallin

lina.vallin@tekniskaverken.se

Thank you for your attention!!