Post on 04-Jul-2015
ainiaSite-adapted energy crops for biogas production cultivated under non-irrigated conditions in the Comunidad Valenciana(Spain)
Paz Gómez
29.08.2011 Vienna, Austria
AnalysisContent
• Introduction and aim
• Methods
• Results and Discussion
• Conclusions
Introduction and aim
Introduction and aim
Introduction
• Climate change and rural development (Castilla la Mancha & Com. Valenciana)
• High number of pigs farms in inland villages of CV. But lack of co-substrates
• High percentage of non-irrigated land (<700 mm of annual pluviometry)
• Soil conditions of arable land: low organic matter, high percentage of carbonates, loam soils
Aim of the study
• To evaluate different site-adapted energy crops for biogas production which were cultivated under non-irrigated conditions
• Cultivation of energy crops
• Batch test
• Estimation of methane potential per surface unit
Methods
Analysis
Cultivation
• Crops VARIETIES. Triticale (cv. Bondadoso), Barley (cv. Oralia; cv. Unia), Oat (var. Prevision), Mixture of ryegrass (45% cv. Trinova; 40% cv. Braulio) and clover (8% cv. Paradana; 7% cv. Laser).
• Location: CASTELLON
• Weather & Soil CONDITIONS
• Thermal integral
• Annual pluviometry
• Soil conditions
• HARVEST TIME considering TS for ensiling and max. biogas potential awaited in relation to maturity scale (BBCH scale)
• ENSILING at pilot scale (MONITORING OF TS, VS)
Methods
Analysis
Batch tests
• VDI Standard 4630
• Inoculum from agricultural biogas plant
• Digester volume: 2L
• Incubator at 38ºC ± 2ºC
• Biogas production: counter 1 mLresolution
• Gas analysis. Measurement range CH4 and CO2 sensors: 0-100%
Methods
Results and Discussion
Results
Cultivation
After ensilingAfter harvesting
Crop Mat. Stage(BBCH)
TS1
(%)VS1
(TS%)Cropyield(t/ha)
TS2
(%)VS2
(TS%)
Triticale 77-83 32.44 93.49 21.25 20.50 88.90
Oats 71-81 27.13 93.65 23.20 17.90 80.70
Barley 77-83 48.40 (1)
95.77 (1)
15.50 (1)
23.19 (2)
80.92 (2)
R&C 59-60 30.92 93.75 6.00 25.10 79.30
1: Barley (cv. Oralia); 2: Mixture of Oralia and Unia varieties (ensiled together) .
Mean values (not available standard deviation)
Results
Biogas Potential Test
0
100
200
300
400
500
600
700
0 10 20 30 40 50 60
Time (days)
Bio
gas
[NL/kg
VS
]
Triticale (cv. Bondadoso)
Oats (cv. Prevision)
Barley (cv. Oralia; cv. Unia)
Mixture ryegrass (cv. Trinova; cv. Braulio) and clover (cv. Paradana; cv. Laser)
58%58%54%
58%
CH4 (%)
Results & Discussion
Methane
(Nm3/tVS) (Nm3/ha)(Nm3/kg seeds
sown)(Nm3/L
rainwater)
Triticale 353 1,368 9 1.1
Oats 314 1,051 7 n.a.
Barley 280 814 6 0.6
Mixture R&C 221 264 2 0.2
Estimation biogas potential per surface unit
Discussion
• Maximum methane potential per hectare estimated between 264-1,368 Nm3CH4/ha
• Triticale shows best results for methane potential per hectare, per kilogram of seeds sown or per liter of rainwater. Most suitable under those cultivation conditions.
• Methane potential per hectare of TRITICALE tested under DRY conditions was 20% LOWER than under WET conditions (1,700 Nm3/ha; FNR, 2010)
• Barley and Oat showed “similar” results of biogas potential per unit of volatile solids. Nevertheless, methane potential per hectare was HIGHER for OATS.
Conclusions
Conclusions
• Under non-irrigated conditions triticale and oats showed the best estimated results of maximum methane potential per unit of surface (both over 1,000 Nm3 CH4/ha).
• Barley showed a good biodegradability and a better maximum slope of accumulated biogas production than oats. Nevertheless, methane potential per volatile solid unit was higher for oats. Therefore, at bigger scale should be analyzed in detail which is the most suitable crop for biogas production considering crop yield per hectare of each specific area, total solids after ensiling as well as volatile solids.
• The mixture of ryegrass and clover, with a potential per surface unit of 264 Nm3CH4/ha seemed to be an inappropriate alternative for the studied areas with low pluviometry. But it´s needed further research in order to evaluate its suitability for biogas production as a rotation crop in those areas.
This research was carried out with funding from The Spanish Ministry of Environment and Agriculture (Ministerio de Medio Ambiente, Rural y Marino), under the Project ENERAL. http://eneral.info/
ainiaThank you for your attention!
pgomez@ainia.es