We live in a time when the population grows explicitly and therefore it’s required a larger arable land a greater number of factories. It is clear that this situation cannot pass without the different types of waste such as agricultural waste, industrial waste and municipal waste. In the cities, it is impossible to control the huge amounts of waste, especially if there is no law that regulates it. Waste incineration is imposed as the only long-term solution to this problem.
Burning (incineration) is a modern thermal way of waste destruction, with the aid of heat. It aims to reduce the volume of waste (up to 90%), and for the energy production – thermal energy and / or electricity. Incineration of waste is carried out in special furnaces that operate within the waste incineration plants.
The first incineration furnaces, which are simultaneously used for energy production, have emerged in the second half of the 19th century. Installations for the incineration of municipal solid wastes are similar to thermal power plants and heating plants according to their characteristics.
Modern incinerators (furnaces for burning waste) are mainly environment friendly and they include pollution mitigation equipments like a flue gas cleaning and others. Today, there are various types of waste incinerator design that use different thermal technologies. The most common incinerators are:
- Burn pile (burn pit) – One of the earliest and the simplest method of the waste incineration. It consists of the combustible waste materials that are piled on bare ground (mainly some forested land for farming) and simply set on fire.
- Burn barrel – It is a more controlled form of waste incineration, containing the burning waste materials inside a metal barrel, with a special grating over its exhaust.
- Moving grate – The typical incinerator for all municipal solid wastes. This grate enables the easy movement of solid waste through the combustion chamber. A single moving grate can handle up to 39 tons of municipal solid waste per hour.
- Fixed grate – It’s the simpler and older kind of incinerator. Fixed grate consists of a brick-lined cell, fixed metal grate, one opening for waste loading and another opening (at the top or on the side) for removing incombustible materials – so-called clinkers.
- Rotary-kiln – with 2 chambers for incineration: a primary and secondary chamber.
- Fluidized bed – Modern waste incineration technology that uses a strong airflow.
All new waste incineration plants must meet certain emission standards, such as environmental standards for sulfur dioxide (SO2), nitrogen oxides, heavy metals, dioxins and other. These plants use two basic methods for energy production:
- Thermochemical conversion, which represents the generation of energy and fuel by thermal decomposition of organic matters.
- Biochemical conversion – the process of obtaining methane, which is based on the enzymatic decomposition of organic matter by microorganisms.
Waste incineration is one of the technically most advanced waste management options that are available today. Besides this method, there are other available technologies for production of waste energy: gasification, pyrolysis, plasma gasification process, and so on. However, incinerators have proven to be the best and most effective solution.