Municipal Solid Waste to Energy Generation in Bangladesh: Possible Scenarios to Generate Renewable Electricity in Dhaka and Chittagong City
Table 1
Overview of major WtE technologies.
WtE technology
Description
Conversion efficiency (MWh/ton MSW)
Service life (year)
Typical MSW input heating value (MJ/Kg)
Max fuel moisture (%)
Input
Products
Waste incineration
Mixed MSW incinerated in a boiler and equipped with CHP plant. Incineration temperatures usually between 1000 and 1200°C.
0.5
30
8–10.5
40–50
Mixed MSW
Electricity and heat.
Pyrolysis
Thermochemical decomposition of organic fraction of MSW at low temperatures in the presence of limited oxygen or in the absence of oxygen. Operating temperatures usually between 200 and 300°C.
0.3
20
10
Sorted MSW
Liquid oil, char, and gas.
Gasification
Process of reacting the organic fraction of MSW at high temperatures with controlled amount of oxygen and steam to produce carbon monoxide, hydrogen, and carbon dioxide. Operating temperature is >700°C.
0.9
20
16.5
40–50
Sorted MSW
Electricity, CH4, hydrogen, and ethanol.
Anaerobic digestion
Biological process of breakdown of organic fraction of MSW by a consortium of anaerobic microorganisms working synergistically in an oxygen poor environment. Most of the anaerobic digesters are designed to operate in the temperature range of 30–35°C.
0.15
20
2.5
Approx. 97
Sorted MSW
Electricity, heat, and LNG.
LFG gas recovery
Landfill gas (LFG) is a saturated gas consisting of 50% CH4 and 50% CO2 by volume, along with some other trace contaminants. CH4 is trapped to generate electricity.
