Treatment

Electric power of the biogasification facilities (Food waste and human excrement mixture)

· Conditions of the facilities: For the quality standards of discharge water, BOD is less than 100 mg/L, SS is less than 300 mg/L, n-Hexane is less than 300 mg/L. The treatment capacity is 400 households and the quantity of discharge water per day is 49 m³. The construction cost is 206 thousand USD (erection of frameworks is 86 thousand USD, the equipment work is 120 thousand USD, this is just used for treatment of food waste by using the combined treatment plant of food waste and human excrement). The persisting period is 10 years and the annual quantity to treat food waste is 0.192 tons.

· Energy consumption of the biogasification per 1.7 tons of food waste and human excrement mixture: 1147 kWh (= 688 kWh × 1.6667 ton-mixed waste).

· Biogas to electric power per 1.7 tons of food waste and human excrement mixture: 502 kWh (= 168 Nm³ × 9.953 kWh/Nm³ × 0.3%).

· Construction cost per 1.7 tons of food waste and human excrement mixture: 447 USD (= 268 USD × 1.6667 ton-mixed waste).

· Electricity cost per 1.7 tons of food waste and human excrement mixture: 63 USD (= 38 USD × 1.6667 ton-mixed waste).

· Maintenance per 1.7 tons of food waste and human excrement mixture: 79 USD (= 47.4 USD × 1.6667 ton-mixed waste).

· Saving cost by biogas to electric power on site: 28 USD (= 502 kWh × 0.0551 USD/kWh).

GHG avoided effect(LNG saving effect) due to utilization of biogas

· Conditions of calculation: 50.8 kg of CO₂ equiv. is generated when LNG, which is applicable to the caloric value, 1 MJ is produced.

· Collection calorie per 1.7 tons of mixture: 6.02 MJ (= 168 Nm³ × 8560 kcal/Nm³ methane × 4.1865 × 10⁻⁶ MJ).