1. Introduction 2. Co-substrates and biogas yields 3. Basic principle of anaerobic digestion 4. Biogas plants for organic substrates 5.

Transcription

1 Short introduction to renewable Energy from Biogas 1. Introduction 2. Co-substrates and biogas yields 3. Basic principle of anaerobic digestion 4. Biogas plants for organic substrates 5. Summary

2 Suitable Substrates for Biogas

3 Quantity of Substrates available Liquid manure Residual waste Food waste Biowaste Clarification sludge Waste from processing of fruit and vegetables Organic waste fromgardens and parks Marc and preclarified effluent from wine manufacture Amount of waste [1.000 Mg DS/ a] in Germay

4 Biogas potential of organic Waste (Germany) Total potential: approx. 4,300 MW el. pot. biogas yield [mio. m³/ a] Liquid manure Residual waste Waste food Biowaste Clarification sludge Waste from processing Fruit and vegetables Organic waste from from parks and gardens Marc and preclarifiied effluent from wine manufacture

5 Anaerobic Digestion / Fermentation

6 Temperatures ranges for microorganisms involved Source: Schlegel, H. G. (1992): Allgemeine Mikrobiologie, Georg Thieme Verlag, Stuttgart.

7 Jul 03 Sep 03 Nov Biogas production CH 4 Temperature Jan 04 March 04 May 04 Jul 04 Sep 04 Time [Month] March 03 May 03 Jan 03 CH4-content [%] Temperature [ C]

8 Metabolism Aerobic metabolism Anaerobic metabolism (Biogas) Source: Schlegel, H. G. (1992): Allgemeine Mikrobiologie, Georg Thieme Verlag, Stuttgart.

9 Technical applications (1) Simple biogas plant for production of cooking gas for a single household

10 Technical application (2) Agricultural biogas plants Source: Biogas Weser-Ems GmbH

11 Technical application (3) Biogas plant, Radeberg Co-fermentation of clarification sludge and biowaste Source: Bio-Verwertungsgesellschaft Radeberg mbh

12 Energy utilisation - combined heat and power plant

13 Benefits of renewable energy from biogas Cost-effective energy supply A sustainable infrastructure for organic waste management can be put in place with biogas plants Decentralised plants have a positive effect on regional development (jobs, fiscal revenues, decentralised electricity and thermal energy production). Primary energy sources (fossil fuels) are replaced by renewables, thus combating global warming and conserving non-renewable resources. High quality fertiliser is produced from secondary raw materials, which substitutes for mineral fertiliser (e.g. phosphate). They are sanitised, contain no germinating plant seeds and are free of pathogens (tobacco mosaic virus, Salmonella...) have a low pollutant content (depending on the materials used) are well tolerated by plants, form humus, and help to prevent soil errosion.

14 Summary There is a wide range of organic substrates with a high biogas potential. Plant designs are available for the diverse applications (from individual homes to large-scale industry). The technical risk is small. As many examples show: Biogas plants are a cost-efficient option and can compete with other solutions.

15 Specific Biogas yield (1) TS ots Specific Biogas yield Substrate [%] [% TS] [m³ CH 4 /kg TS] [m³ CH 4 /kg ots] Literature min max min max min max min max Agricultural waste 0,19 0,26 [11] 1) Animal cadaver meal ,45 0,72 0,50 0,80 [3] 2) Biowaste ,08 0,12 0,15 0,60 [16] 1) Blood meal [3] 2) Buffalo wastes 19 0,07 [15] Cane trash 0,10 [11] 1) Cattle dung (fresh) ,12 0,33 0,18 0,50 [3] 2) [10] 1) Cattle manure-feces 0,05 0,19 [11] 1) Cattle manure-liquid ,04 0,25 0,10 0,28 [3] 2) [4] [7] 1) [1] 1) [10] 1) Cereal slop ,30 0,52 0,43 0,70 [3] 2) [10] 1) [16] 1) Cheese waste 79 0,67 [13] Chicken dung ,07 0,09 0,25 0,45 [16] 1) Chicken manure-liquid ,13 0,34 0,18 0,43 [3] 2) [4] [1] 1) [10] 1) Clarification sludge ,21 0,28 0,23 0,41 [6] 1) [2] [10] 1)

16 Maize straw Biowaste (domestic) Food waste (large canteen) Residual waste Liquid manure from cattle Clarification sludge Specific Biogas yield (2) Spec. biogas yield [m³ CH4 /Mg original sub.]

17 Substrate characteristics, e.g. CN-ratio C/N ratio of different substrates [Bilitewski et al., 1991] Substrate Household waste Kitchen waste Sewage sludge Wheat straw Sawdust Agricultural soil C/N ratio