Irini Angelidaki, Kanokwan Boe and Lars Ellegaard. Environment & Resources Technical University of Denmark

Transcription

1 Irini Angelidaki, Kanokwan Boe and Lars Ellegaard

2 Presentation content Biogas in Denmark: A typical Centralized Biogas Plant Main Results of the investigation Conclusions

3 Location of Centralized biogas plants in Denmark

4 Typical centralized biogas plant Ribe biogas plant

5 Full-scale investigation Process stability Process efficiency Microbiology

6 Potential methods to improve recovery efficiency from manure - Increase stabilily of the digestion process - Pre-treatment of incoming substrate (to increase degradability) - Increase retention time of the manure reactor(s) - Arrange post-digestion systems (to increase degradation efficiency)

7 Stability in Danish Biogas Plants Total VFA (g/l) Apr-02 Jun-02 Aug-02 Oct-02 Dec-02 Jan-03 Apr-03 Jun-03 Aug-03 Oct-03 Date Blaabjerg Blaahoej Fangel Farsø Filskov Grindsted Hashøj Lemvig Lintrup Nysted Revninge Sinding-Oerre Snertinge Studsgaard Thorsø I Vaarst-Fjellerad I Vegger I Århus I

8 Correlation between ammonia and VFA. VFA, g/l Ammonium, g/l

9 Residual methane production 55 o C 25 o C 20 o C 15 o C 55 o C 55 o C 25 o C 20 o C 15 o C

10 Residual methane production 7 6 ml-ch4/ml-sample oc 25 oc 20 oc 15 oc Time (days)

11 Residual methane production Sluttab - metan tab Vester Hj. Feb-04 Århus m mar-04 Blåbjerg jun-03 Snertinge feb-04 Nysted mar-04 Hashøj jul.03 Lemvig mar-03 Revninge mar-04 Lintrup aug-03 Vaarst Fj. Mar-04 Thorsø feb-04 Blåhøj mar-04 Vegger feb-04 Fangel feb-04 Studsgård feb-o4 Århus t mar-04 Filskov okt-03 Sinding Metan (m3/m3-biomasse)

12 Restgastab i forhold til total produktion Tab i forhold til praktisk opnåelig produktion Termofil Mesofil Term+mes Sinding Århus samlet mar-04 Snertinge feb-04 Thorsø feb-04 Nysted mar-04 Lintrup aug-03 Hashøj jul.03 Lemvig mar-03 Fangel feb-04 Revninge mar-04 Blåhøj mar-04 Vaarst Fj. Mar-04 Vegger feb-04 Studsgård feb-04 Filskov okt-03 >15% 10-15% < 10% Vester Hj. Feb-04 % Blåbjerg jun-03

13 Temperature and residual methane 30 Tab i forhold til praktisk opnåelig produktion Termofil Mesof il Blåbjerg jun-03 Sinding Snertinge feb-04 Thorsø feb-04 Lintrup aug-03 Lemvig mar-03 Blåhøj mar-04 Vaarst Fj. Mar-04 Vegger feb-04 Studsgård feb-04 Filskov okt-03 Vester Hj. Feb-04 Nysted mar-04 Hashøj jul.03 Fangel feb-04 Revninge mar-04 %

14 Distribution of the total methane potential OPTIMAL TOTAL CH4 PRODUCTION m3-ch4/m3-bio 10 0 Vegger Hashøj Vaarst Fj. Vester Hj. Stutgard Nysted Revninge Blåhøj Snertinge Filskov Blabjerg Fangel Lintrup-aug-02 Lintrup-aug-03 Lintrup-jan-03 Ribe Thorsø Reactor production (on the bottom) After-Storage production (in the middle) Lost production (on the top)

15 Main reactor residual methane loss versus retention time % restidual loss HRT (days) Mesophilic plants Thermophilic plant

16 Temperature effect on residual biogas potential Relative overall activity 120% 100% 80% 60% 40% 20% 0% Post digestion temperature (oc) Thermophilic Model curve Thermophilic Mesophilic Model curve Mesophilic

17 INCREASING TEMPERATURE Samples previously incubated at C for a long period have been moved to process temperature (37-54 C): m3-ch4/ m3-bio Revninge Time (d) Spec. Prod. At 10 C Spec. Prod at 37 C Spec. Prod from 10 cto 37 C m3 CH4/m3 Bio Studsgård (R) Time (d) Spec. Prod. at 54 C Spec. Prod at 15 C Spec. Prod from 15 C to 37 C spec. Perod from 15C to 54C

18 SITUATION: INNOVATIVE SOLUTIONS The majority of the biogas plants have Reactors with good efficiency; Many plants are loosing a lot and the gap between the theoretical and the practical potential is still wide; MAIN OBSTACLE: hydrolysis is the real rate limiting step for the further methanogenesis increase HRT to provide a better substrate hydrolysis SOLUTIONS: TRADITIONAL SOLUTIONS INNOVATIVE SOLUTIONS Increase the HRT in main reactor New process configurataion: Utilization of the After-Storage.

19 Conclusions Significant amounts of CH4 are lost (5-30%) Plants with HRT< 15 days are lossing more CH4 from the main reactor Post-digestion is highly influenced by the temperature Post-digestion at low temperature are increasing the total methane potential of the material Manure-plants are dominated by Methanosarcina, while sludge plants by Methanosaeta.

20 Acknowledgements The study was funded by the Danish Energy Agency, Development of Renewable Energy The operational staff of the Biogas Plants participating in the investigation is greatly acknowledged Researchers: Kanokwan Boe Lars Ellegaard Dimitar Karakshlev Damien Batstone Irini Angelidaki Students: Simone Labo Lucía Fernández García Eva Arler He Zhen Chao Pan Troels Hilstrøm Søren H. Laursen Technicians: Hector Garcia Majbrit Staun Jensen