Table 2 Advantages and disadvantages of different WtE technologies [90]

Anaerobic digestion

Energy recovery with the production of high grade soil conditioner

Unsuitable for wastes containing less organic matter

No power requirement for sieving and turning of waste pile

Requires waste segregation for improving digestion efficiency

Enclosed system enables trapping the gas produced for use

Controls GHG emissions

Free from bad odour, rodent and fly menace, visible pollution and social resistance

Compact design needs less land area

Net positive environmental gains

Can be done in small scale

Landfill with gas recovery

Least cost option

Surface runoff during rainfall causes pollution

Gas produced can be utilised for power generation or direct thermal application

Soil and groundwater may get polluted by the leachate

Skilled personnel not required

Yields only 30–40% of the total gas generated

Natural resources are returned to the soil and recycled

Large land area required

Can convert marshy lands to useful areas

Significant transportation costs

Cost of pre-treatment to upgrade the gas to pipeline quality and leachate treatment may be significant

Spontaneous explosion due to methane gas buildup

Incineration

Most suitable for high calorific value waste

Least suited for aqueous, high moisture content, low calorific value and chlorinated waste

Units with high throughput and continuous feed can be set up

Toxic metal concentration in ash, particulate emissions, SO_x, NO_x, chlorinated compounds, ranging from HCL to dioxins

Thermal energy for power generation or direct heating

High capital and O&M costs

Relatively noiseless and odourless

Skilled personnel required

Low lands are required

Can be located within city limits, reducing transportation costs

Hygienic

Pyrolysis/Gasification

Production of fuel gas/oil, which can be used for various purpose

Net energy recovery may suffer in waste with excessive moisture

Control of pollution superior as compared to incineration

High viscosity of pyrolysis oil may be problematic for its burning and transportation