The authors have quantified material and energy flows in two options of co-treatment of organic
fractions of wastes by composting, and by anaerobic digestion. The results shown thermophilic anaerobic
co-digestion of septic tank sludge, sewage sludge and organic municipal solid waste has provided the
biogas yield of 19.6 m3 per ton of mixed waste, equal to 114 kWh of heat and power. The calculation for
the case of Long Bien district, Hanoi city has shown anaerobic co-digestion of waste fractions could
generate 111,220 kWh of heat and power per day, helping the waste treatment complex to be selfsufficient
in terms of energy. Besides, 32.2 MWh/day of surplus energy could be sold to the grid. This
option also reduced emission of greenhouse gases versus composting. The study can be used as basis for
cost-benefit analyses in selection of appropriate urban waste management options aiming at efficient
utilization of engineering infrastructure systems, waste treatment and resource recovery