Fig. 8.2: Costs and benefits of a fixed-dome biogas plant
Fig. 10.1: Conceptual drawing of a floating-drum biogas plant
Fig. 10.2: Constructional drawing of a floating-drum plant
Fig. 10.3: Constructional drawing of a waterjacket plant
Fig. 10.4: Constructional drawing of a cylindrical floating-drum plant for quarrystone masonry
Fig. 10.5: Conceptual drawing of a fixed-dome biogas plant
Fig. 10.6: Constructional drawing of a fixed-dome plant
Fig. 10.7: Constructional drawing of an earth-pit biogas plant with plastic-sheet gasholder
Fig. 10.8: Schematic diagram of earth-pressure and water-pressure forces
Fig. 10.9: Nomogram for correcting gas pressures/temperatures
Fig. 10.10: Nomogram for finding the net calorific value of biogas as a function oftemperature
pressure and moisture content
Fig. 10.11: Fundamental geometric formulae
10.7.2 Tables
Tab. 2.1: Detailed planning guide for biogas plants
Tab. 3.1: Climate zones and their suitability for biogas plants
Tab. 3.2: Standard liveweight values of animal husbandry and average manure yields (dung +
urine) as percentages of liveweight
Tab. 3.3: TS- and VS-contents of green plants
Tab. 3.4: Digestion characteristics of animal-husbandry residues
Tab. 3.5: Mean gas yields from various types of agricultural biomass
Tab. 3.6: C/N-ratios of various substrates
Tab. 3.7: Biogas compatibility of farm types
Tab. 3.8: Survival time of pathogens in biogas plants
Tab. 3.9: Concentration of nutrients in the digested slurry of various substrates
Tab. 3.10: Effects of digested slurry on crop yields
Tab. 4.1: Outline for determining biogas demand
Tab. 4.2: Outline for determining biomass incidence
Tab. 4.3: Simplified gas-yield values for substrate from cattle and pigs
Tab. 5.1: Basic criteria for acetobacters (acid forming bacteria) and methanobacters
(methaneforming bacteria)
Tab. 5.2: Energy potential of organic compounds
Tab. 5.3: Energetical comparison of aerobic and anaerobic fermentation
Tab. 5.4: Temperature ranges for anaerobic fermentation
Tab. 5.5: pH ranges for biomethanation
Tab. 5.6: Substances with an inhibiting effect on biomethanation
Tab. 5.7: Comparison of various plant designs
Tab. 5.8: Common substrate mixing ratios
Tab. 5.9: Mortar mixing ratios
Tab. 5.10: Suitability tests for rendering/mortar sands
Tab. 5.11: Quality ratings for various dome-sealing materials
Tab. 5.12: Properties of plastic sheeting - gasholder suitability ratings
Tab. 5.13: Gas-pipe pressure losses
Tab. 5.14: Composition and properties of biogas and its constituents under s.t.p. conditions (0 °C,
1013 mbar)
Tab. 5.15: Pointers on flame adjustment
Tab. 5.16: Comparison of various internationally marketed biogas burners
Tab. 5.17: Biogas consumption for cooking
Tab. 5.18: Tests for biogas cookers/stoves
Tab. 5.19: Standard lighting terms and units of measure
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