Standortangepasste Anbausysteme für Energiepflanzen Optimized growth and preservation of energy crop M. Heiermann, C. Herrmann, C. Idler, V. Scholz Leibniz-Institute for Agricultural Engineering Potsdam-Bornim IEA/CROPGEN workshop 15 th Int. Biomass Conference Berlin, 8 th May 2007
Preservation of energy crops Overview EVA-Subproject IV Methods Results Conclusion
EVA-Subproject IV: Ensiling/Biogas process steps cultivation harvest ensilage biogas production influencing factors objectives plant species harvest time chopping length additives high yielding low losses duration of storage high gas production potential process conditions
Methods Lab scale silos 1.5-litre glass silos Storage: 25 C, 90 days Anaerobic digestion Batch test, 2.0-litre bottles Conditions: 35 C, 30 days
sunflower; n=4 fodder radish; n=20 J. artichoke haulm; n=16 Plant species - Biogas Silages (n=162) 1000 900 800 700 600 500 400 300 200 biogas yield [Nl/kg ODM] 100 0 maize; n=32 spring barley; n=20 forage grass; n=16 spring rye; n=9 pea/oat/false flax; n=5 oat; n=8 sweet sorghum; n=4 forage sorghum; n=20
maize; n=32 J. artichoke haulm; n=16 Plant species - Methane Silages (n=162) 65 60 55 50 methane content [Vol-%] 45 sun flower; n=4 pea/oat/false flax; n=5 forage grass; n=16 fodder radish; n=20 spring rye; n=9 sweet sorghum; n=4 forage sorghum; n=20 oat; n=8 spring barley; n=20
Plant species Harvest time Silages 500 400 300 200 100 0 milk early dough milk early dough end of stem elongation inflorescence development of fruit ripening heading early dough flowering completed milk methane yield [Nl/kg ODM] spring rye oat/pea/ false flax Jerusalem artichoke sun flower forage sorghum sweet sorghum plant species / growth stages
Impact of ensiling process 250 200 150 100 50 0 fresh material silage fodder radish J. artichoke n=20 n=1 n=5 n=7 n=2 n=4 n=4 n=16 n=2 n=4 n=5 n=4 n=2 n=8 n=12 n=32 CH4 yield [Nl/kg harvested material] n=5 n=20 n=2 n=16 n=4 n=20 Methane yield Y FM > Y Silage Y Silage > Y FM spring barley spring rye sweet sorghum forage grass sun flowers oat/pea/false flax oat maize forage sorghum
Ensiling process: Fermentation quality Plant species Very good [%] Maize 98 Good [%] Forage grass 92 8 Alfalfa/grass 100 Mean [%] Poor [%] Very poor [%] Spring rye 50 8 34 8 Spring barley 79 17 4 Oat 60 33 7 Triticale 67 33 Forage sorghum 100 Sweet sorghum 100 Sun flowers 75 12.5 12.5 J. artichoke 100 Fodder radish 21 12.5 54 12.5 Classsification according to DLG-code
Ensiling process: Additives Additives Active substance Effect MAIS KOFASIL LIQUID Chemical additive aerobic stability BIOSIL BONSILAGE PLUS SILASIL ENERGY Bacterial culture homofermentative strains Lactobacillus plantarum Homofermentative and heterofermentative lactic acid bacteria Selected homofermentative and heterofermentative lactic acid bacteria strains fermentation aerobic stability + fermentation enhanced acetic acid production
Ensiling process: Silage quality Additve DMcontent DMloss ph LA AA* BA** Alcohol [%FM] [%] [%DM] [%DM] [%DM] [%DM] None 35.0 7.8 3.6 2.7 1.1 1.1 1.3 MAIS KOFASIL 34.2 6.3 3.5 2.8 3.3 0.0 1.3 BIOSIL 36.4 2.8 3.3 4.8 0.5 0.0 1.1 BONSILAGE PLUS SILASIL ENERGY 34.9 3.8 3.6 2.8 0.3 0.1 0.1 36.5 1.7 3.9 0.8 3.7 0.0 1.3 * acetic- und propionic acid ** isobytric-, butric-, isocaproic-, caproic-, isovaleric-, valeric acid
Ensiling process: Additives Maize biogas yield [Nl/kg ODM] 1000 900 800 700 600 500 400 300 200 100 0 fresh matter silage no additive MAIS- KOFASIL BIOSIL BONSILAGE PLUS SILASIL ENERGY
Ensiling process: Additives Maize 350 300 250 200 150 100 50 0 fresh matter silage no additive MAIS- KOFASIL BIOSIL BONSILAGE PLUS SILASIL ENERGY biogas yield [Nl/kg harvested material]
Ensiling: Duration of storage Maize + Additive 900 biogas yield [Nl/kg ODM] 800 700 600 500 400 300 200 100 0 0 10 90 180 365 anaerobic storage [days]
Conclusion Numerous plant species are suitable for anaerobic digestion achieving high gas yields Variations of biogas yield within crop species depend on site-specific conditions, variety, cultivation intensity Maize is the preferable plant species followed by forage sorghum, triticale and spring barley Harvest time has an impact on methane formation process via chemical composition of plant material Maturity stage at harvest also affects biomass yield and ensiling process (fermentation quality) Additives investigated have a positive effect on silage quality and minimised DM-losses Investigated storage periods (up to 365 days) for whole crop silages show no negative effect on biogas yield
Standortangepasste Anbausysteme für Energiepflanzen Thank you! Proceedings "Parameters Influencing Substrate Quality and Biogas Yield" Poster Group IV: Visual Presentation VP T1.3 Wednesday, 9 May 16:45-18:10 www.atb-potsdam.de