Anaerobic Digestion
Resource Potential
In Hong Kong, the potential substrates for anaerobic digestion are organic municipal solid wastes, sewage sludge and livestock wastes. The resource available for a particular site can be estimated using following formulae.
Organic municipal solid wastes (MSW)
Annual energy from anaerobic digestion of MSW (MWh)
| = |
annual MSW production (tons) X heating value of biogas generated by each ton of raw MSW (MJ/ton) X typical thermal efficiency of biogas electricity generator (%) X 1/3600 (MWh / MJ) |
Where
- heating value of biogas generated by each ton of raw MSW = 2,258 MJ / ton
- typical thermal efficiency of biogas electricity generator by using gas turbine = 35%
Sewage sludge
Annual energy from anaerobic digestion of sewage sludge (MWh)
| = |
annual sewage sludge production (tons) X heating value of biogas generated by each ton of dry solid sewage sludge (MJ/ton) X typical thermal efficiency of biogas electricity generator (%) X 1/3600 |
Where
- heating value of biogas generated by each ton of dry solid sewage sludge = 3,546 MJ / ton
- typical electrical conversion efficiency from landfill gas utilization by using gas turbine = 35%
Livestock wastes
The formula is similar to the one for sewage sludge.
