Energy from Organic Waste Biogas Plants Michael Köttner

Transcription

1 Energy from Organic Waste Biogas Plants Michael Köttner Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 1

2 Activities of IBBK related to biogas technology Know-how transfer (international workshops, conferences, study tours, training) Technical support especially with dry digestion, lagoon technology, small scale installations Contacts to experts in planning, design and construction Contacts to specialized companies Networking with members in different regions, nationally and internationally Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 2 2

3 What is biogas? Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 3

4 Biogas definition Methane CH % Carbon dioxide CO % Water Vapour H % Nitrogen N % Oxygen O % Hydrogen sulphide H 2 S 0 1 % Hydrogen (hydrolysis) H % Ammonia NH % Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 4

5 Biogas definition Biogas is produced through the anaerobic degradation of organic material by microorganisms Framework conditions for good production: Anaerobic condition absence of air/oxygen The organic material must be readily available no lignocellulose Sufficient moisture at least 50 % Constant temperature (mesophilic: C, thermophilic: C) Constant feed quality Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 5

6 Biogas usage methods Source: Fachverband Biogas Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 6

7 Feedstock for biogas production in Germany 6% 7% 48% 44% 77% Industrial and agricultural residues Energy crops Liquid and solid manure Biowaste 13% 2% 3% % by weight % by energy input Source: Fachverband Biogas Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 7 7

8 Biogas potentials of various bio-waste Source: Fachverband Biogas Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 8

9 Biowaste treatment technologies Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 9

10 Process selection criteria Utilization of biowaste Material Material/Energetic Energetic Composting/ Direct utilization Anaerobic digestion Incineration Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 10

11 Composting / Dry Fermentation Process selection criteria Water content Garden waste Household-waste (rural) Household-waste (urban) Organic industrial waste Kitchen waste Food waste Catering waste Slaughterhouse waste Wet Fermentationtion Structure Source: Wiemer & Partner 1994 Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 11

12 Process comparisons Wet fermentation Dry fermentation Continuous process Discontinuous/ Batch process Source: Fachverband Biogas Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 12

13 Biogas producing techniques Wet fermentation Dry fermentation Continuous process Discontinuous/ Batch process Source: Fachverband Biogas Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 13

14 Biogas producing techniques Wet fermentation Dry fermentation Continuous process Continuous feeding and removal of small quantities of substrate Discontinuous/ Batch process Source: Fachverband Biogas Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 14

15 Biogas producing techniques Wet fermentation Dry fermentation Continuous process Discontinuous/ Batch process During the digestion the substrate is neither added nor removed from the digester Source: Fachverband Biogas Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 15

16 Wet fermentation of Biowaste Advantages: Good separation of organic and impurities Good substrate digestion Good suitability for commercial biowaste Disadvantages: Complex (preparation) High energy consumption High wear Sedimentation TS approx. 12% or less Energy requirement: Approx. 10% of the plant s electricity production Minimum input: approx t/year Maximum input: approx t/year Gas production: approx Nm 3 /t FM Others: mostly external hygienisation Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 16

17 Dry fermentation of Biowaste Advantages: If modular only 1 module is affected in case of process problems High loading volume High solids content: 30-40% TS Disadvantages: Emission during batch loading Struvite deposits in the percolate system Lower productivity Energy requirement: Approx. 3-5% of the plant s electricity production Fuel for wheel loaders Minimum input: approx t/year Maximum input: approx t/year Gas production: approx Nm 3 /t FM longer operation for more uniform gas quality Others: necessary hygienisation by composting Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 17

18 Design parameters for a 1 MW wet digestion plant Input Expired foodstuff Mg/a Water Mg/a Mixed waste Mg/a Oil and fat Mg/a Total input Mg/a Output Digestion Residue Mg/a Biogas Mg/a Packaging and Metals Mg/a Total output Mg/a Energy Electrical energy 6,70 Mio kwh/a Thermal energy 7,00 Mio kwh/a Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 18

19 Exemplary Dates of Biowaste Treatment Hamburg, Germany : Submission of application : Permit granted for construction : Foundation of BIOWERK Hamburg GmbH & Co. KG : Begin of construction on site : Permit granted for operation : First engine test with Biogas : Official opening of the plant : Start of the operating test Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 19

20 Operational problems; important issues Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 20

21 Pretreatment of the feedstock in wet digestion Particle size reduction Extracting organic material from packaging Impurities separation Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 21

22 Inhomogeneous feedstock problems Dishes, cutlery, etc.. Plastic bags Bones, egg and seashells Glass, etc.. Issues: mechanisms blocked or broken by material Solution : separation of impurities Wet digestion: pre-treatment necessary Dry batch digestion: less sensitive to impurities post-treatment Source: FINSTERWALDER UMWELTTECHNIK Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 22

23 Feedstock Removal of impurities from a wet digester Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 23

24 Biological problems Issues: Ammonia level is high Feeding too high or retention time too short (Buffer capacity) Lack of trace elements/high sulfur Inadequate mixing Fast temperature decrease e.g. due to failure in heating systems Inhibitors (disinfectant, antibiotics) Solutions: Feedstock as constant as possible Periodic check of the biological parameters Supplement of trace elements Thorough inoculation of input substrates is essential Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 24

25 Biowaste digestion processes overview in Europe Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 25

26 Biowaste dry fermentation Continuous process Linde KCA/Strabag process (Germany) Horizontal concrete digester with several paddle stirrers in row Requires thorough crushing and pretreatment of organic wastes Max 25% DM DRANCO process (Belgium) Vertical cylinder, throughout crushing of organic wastes Mixing with already digested matter (1:6) Vertical passage from top to bottom though cylinder Kompogas process (CH), Thöni (AUS) Horizontal steel or concrete digester with long axle paddle stirrer Requires thorough crushing and pretreatment of organic waste Max 25% DM Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 26

27 Strabag Umweltanlagen GmbH (formerly Linde-KCA Umweltanlagen GmbH) The dry digester built as a horizontally arranged, special-concrete, very sturdy compartment Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 27

28 Organic Waste System (DRANCO) First plant built in 1984 Vertical digestion: the material drops vertically by gravitational force Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 28

29 Axpo Kompogas AG The volume of each digester is around 1300 m 3 Retention time in the digester is about days Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 29

30 Biowaste dry fermentation Discontinuous process Garage type digester (communal) Inoculation of substrates and percolation with process water (Biocell, DK. BEKON, Bioferm, DeNaBa, DE.). Additional aerobic pretreatment (Kompoferm, DE. Solon, DK. Pöttinger, AT) Simultaneous wet-dry digestion (agricultural and communal) Helector and BAL, DE. Renergon, CH Solid mater immersion process with flexible cover (agriculture) Erep, CH. Aria-Biogas, Naskeo, FR. Wolferstetter, DE Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 30

31 Bekon Energy Technologies GmbH & Co.KG The standard module has 4 digesters Source: Bekon Energy Technologies GmbH & Co. KG Retention time in the digester is about days Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 31

32 BIOFerm GmbH Biggest plant: 8 digesters and a capacity of 750 kwel Retention time in the digester is about 4 weeks Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 32

33 Eggersmann Anlagenbau GmbH & Co. KG Biogas plant Schweinfurt The standard module has 8 digesters Retention time in the digester is about 21 days pre-process for composting Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 33

34 Digestate management Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 34

35 Use of biogas digestate Digestate can be spread on the fields Before the land application the feedstock/digestate must be hygienized EU animal byproduct regulation, national biowaste ordinance Improved Fertilizer Avoids nutrient losses Reduces burning effect on plants Improves flowing properties, plant compatibility and health Reduces germination ability of weed seeds Environmentally sound Reduces the intensity of odor 3 folded emission reduction effect avoidance of methane, laughing gas and ammonia Reduces the wash out of nitrate through better fertilizer management Recycles organic matter and nutrients Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 35 5

36 Upgrading of the digestate Liquid-solid separation Drying Pelletizing Composting Mineral Organic Fertilizer Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 36

37 Technical and financial success factors Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 37

38 Technical success factors for biowaste digestion systems Substrates need to be suitable for digestion (stackable, structured, contaminant free) Not suitable for the treatment of hazardous wastes Thorough inoculation of input substrate is essential Active bacteria have to be transported to the substrate (dry digestion), fresh biomass is transported to the bacteria (wet digestion) Digestion process has to support the development of appropriate bacteria Applied technology has to suit local conditions, more than 60 % local sourcing possible Plant size has to be designed according to available quality and quality of input substrates Modular design allows future enlargement of the plant Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 38

39 Financial success factors for biowaste digestion systems Continuous supply of suitable substrate Fixed long term waste disposal contracts Availability of trained and motivated personnel Access to the electricity grid at reasonable rates Biowaste disposal fees, e.g. in Europe /t Revenue from biomethane or electricity sales Possibility to utilize excess heat from CHP unit Revenue from sales of compost or dried digestate as secondary fuel Communal projects are largely not profit driven: payback 15 to 20 years But,. bio-methanisation is the only waste treatment technology with a positive energy and revenue balance Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 39

40 Example investment costs Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 40

41 Example capital costs Depreciation Years Building 20 Equipment 10 Gas utilization 8 Mobile machineries 7 Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 41

42 Example operational costs Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 42

43 Example specific treatment costs Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 43

44 Thank you for your attention! Michael Köttner International Biogas and Bioenergy Centre of Competence IBBK Am Feuersee Kirchberg/ Jagst Germany Phone: Fax: m.koettner@ibbk-biogas.de contact@ibbk-biogas.com Waste to Energy Conference 06-07/11/2017 Istanbul, Turkey 44