Municipal solid waste is defined as a waste type consisting of everyday items that are discarded by the public.
Several options are available for the disposal of such types of waste (http://www.conserve-energy-future.com/waste-management-and-waste-disposal-methods.php):
- Landfill: most popular method. It consists of collecting the disposed waste and burying it in assigned lands. The collected waste is treated to eliminate “the odors and dangers of waste before it is placed into the ground”.
- Incineration / Combustion: also referred to as thermal treatment, when the disposed waste is burnt at high temperatures “to convert into residue and geaseous products”.
- Recovery / Recycling: when disposed waste is separated and useful products such as carton, glass, plastic, etc… is reused to produce new products.
- Plasma gasification: the use of plasma which is an “electrically charged or ionized gas” most commonly found in lighting. The plasma produces temperatures higher than 6,983˚C converting the solid or liquid gas into a syngas, a renewable energy.
- Composting: the process of natural biodegradation of the disposed waste.
- Avoidance / minimization: reduction of waste creation.
- Waste to Energy: the process transforms the non – recyclable produce into useful sources for heat, electricity or fuel.
In a publication by the Ministry of environment in collaboration with the UNDP at the end of 2014, the municipal solid waste generated in 2010 was found to be 1.6 million tons and 2.0 million tons in 2013. By the end of 2014, the incremental yearly quantity of waste was equivalent to 324,568tones / year (http://www.lb.undp.org/content/dam/lebanon/docs/Energy%20and%20Environment/Publications/EASC-WEB.pdf).
On the other hand, a recent CEDRO publication referring to records from the Ministry of Energy and Water stated: “In 2009, the total production from thermal power plants was 88% for delivered energy […] energy not supplied (deficit) of 23% of demand” (http://cedro-undp.org/content/uploads/Publication/141229111001882~Energysecurity-thelebanesecaser2.pdf).
Waste to Energy (WtE) is now an available and well-known procedure to treat a very wide range of waste, a heterogeneous material, consisting essentially of organic substances, minerals, metals and water. The intention of waste incineration is to treat wastes so as to reduce their volume and hazard, destroying potentially harmful substances that are, or may be, released during incineration. The target of thermal treatment is to provide an overall environmental impact reduction that might arise from the waste.
The majority of the energy produced during combustion is transferred to the flue-gases which are collected into a recovery boiler, in order to produce superheated steam that is inputted in a steam turbine power generator.
According to the U.S. Environmental Protection Agency, waste-to-energy plants produce electricity with “less environmental impact than almost any other source of electricity.” Clearly, today’s waste-to-energy plants are nothing like those old, polluting incinerators of the past.