ENERGY
Waste to Energy
Waste-to-energy (WtE) or Energy-from-waste (EfW) is the process of creating energy in the form of electricity or heat from the waste. WtE is an energy recovery process. Most WtE processes produce electricity directly through combustion, or produce a combustible fuel commodity, such as methane, methanol, ethanol or synthetic fuels.
Power plants that burn Municipal solid waste (MSW) for energy are called waste-to-energy plants. These plants generate electricity much as coal-fired plants do, except that combustible MSW—not coal—is the fuel used to fire their boilers. The main advantage of burning solid waste is that it reduces the amount of garbage dumped in landfills, which in turn reduces the cost of landfill disposal. It also makes use of the energy in the garbage, rather than burying it in a landfill, where it remains unused.
Waste to Energy
In addition to directly burning MSW, a number of new and emerging technologies can be used to produce energy from waste and other fuels. Compared with direct combustion, many of these technologies possess the potential to produce more electric power from the same amount of fuel. These technologies can separate corrosive components (ash) from the converted fuel, thus it is possible to allow higher burning temperatures in boilers, gas turbines, internal combustion engines, etc. Some technologies can also efficiently convert the energy into liquid or gaseous fuels. Generally these technologies can be divided into two categories, i.e. thermal technologies and non-thermal technologies. The thermal technologies mainly include gasification, thermal depolymerization and pyrolysis. The non-thermal technologies include anaerobic digestion, fermentation production, mechanical biological treatment.