Biogas Training Course. Zagreb January 2010

Transcription

1 Biogas Training Course Zagreb January 2010 Michael Köttner Introduction into digester technology 1

2 Digester types and installation technology Digester Systems Wet Fermentation Completely mixed digester Plug flow digester Dry Fermentation Plug flow digester Garage type batch digester 2

3 Concrete digester with concrete cover Advantages: - Controllable (solid feeding...) - Withstand certain pressures (20 mbar) - Simple repairing of the stirring system - Low heat loss - Wind protection Disadvantages: - No integrated gas holder - Inner digester repair difficult - The concrete is not absolutely gas-tight - Difficult leak identification 3 1

4 Concrete digester with concrete cover 4 1

5 NQ Anlagentechnik Source: NQ Anlagentechnik Casablanca, June 2006

6 Concrete digester with single membrane cover Advantages: - Low-price alternative - Simple digester revision - Integrated gas holder Disadvantages: - Wind- and weather sensitive - Not 100% gas-tight - Difficult to determine gas level 6 1

7 Concrete digester with single membrane cover 7 1

8 Concrete digester with air supported double membrane cover Advantages: - Simple digester repair - Integrated gas holder - Weather proof - Easy to determine gas level Disadvantages: - More expensive than one cover - Not 100% gas-tight - Permanent energy consumption 8 3

9 Concrete digester with air supported double membrane cover 9 3

10 Steel digester combination of material: steel /stainless steel 150 kw Gasmotor Biogasanlage Kompakt 150 Fahrsilos Gasspeicher 200 m³ Gesellschaft für umweltschonende Technologie Reactor: ring in ring concrete container Vorgrube 75 m³ 10 Fermenter: m³ Arbeitsvolmen Nachgärlager: m³ 5

11 Lipp biogas system Cereal, maize corn Mill /Squezee Biomass storage Lactic acid fermentation ph value 4 500m 3 volume = Approx. 350t cereals 50% DS Retention time aprox. 15 days Process water Automated feed-in by gear pump, several times per day 11

12 Combi digester (concrete and stainless steel) Concrete base, ring from V4A (high quality steel) All pipes in stainless steel Combination with double cover possible Gasraum Tragluftdach Gasmembrane Mittelstütze mit Tragbändern Feststoffeintrag Rührwerk Isolierung Beton Edelstahblech Heizung Dichtmasse Gärsubstrat Edelstahlwinkel Beton 12 concrete tank partially in ground 6

13 Horizontal digester with paddle stirrer Advantages: - Digesting high solids content - High loading rate possible - Little short cut flow - Automatic sand drain - Complete mixing - High digester productivity - Suitable for dry digestion Disadvantages: - High price - Post-digestion is needed - Limited in size 13 4

14 Horizontal digester with paddle stirrer Steel or Concrete 14 4

15 System VSP - Pfefferkorn Source: Casablanca, June 2006

16 System BIMA Biogas-Induced-Mixing-Arrangement Sources: & Casablanca, June 2006

17 garage type digester 17 (BEKON, 2005)

18 Dry Fermentation System for Biomass over 20% DM Main Function Torch Leachate distributor Heating Leachate tank Biomass Gas-tight door Co-generator Concrete digester with walls and floor heating Leachate drain system 18

19 Comparison between dry and wet fermentation Criteria Substrate Technique Interferences Plant Failure Process energy Energy density Emissions Tech. application Hygiene High Solid fermentation Fermentable substrate ( max. 50 % VS) Recirculation of leachate, flow, pre-mixture Not applicable Modular, 1-stage batch process only single module affected Low (Recirculation of leachate ) Depending on management Dung and/or compost technology Less problematic (batch process) Homogenisation Formation of sink-, swimming layers and foam Complex, multi-stages continuous processes Whole digester affected High (homogenization) Low Liquid fermentation Pumpable susbstrate (max. 13 % VS) Depending on management Liquid manure technology more problematic 19

20 Thank you for your Attention! Michael Köttner International Biogas and Bioenergy Centre of Competence IBBK Am Feuersee Kirchberg/ Jagst Germany phone: fax: info@biogas-zentrum.de