This Waste Incineration Essay example is published for educational and informational purposes only. If you need a custom essay or research paper on this topic, please use our writing services. EssayEmpire.com offers reliable custom essay writing services that can help you to receive high grades and impress your professors with the quality of each essay or research paper you hand in.
His torically, and even today in some developing countries, the easiest way of disposing of waste has been to burn it in open air. Incineration of raw waste has been practiced throughout the history of humanity in the most crude form of incineration: Indiscriminate burning. The indiscriminate open burning of waste on a large scale, however, causes air, water, and soil pollution. Current incineration technology has come a long way from open burning to sophisticated incinerators. The purpose of burning has also changed from simply getting rid of waste to reducing waste volume and recovering energy. Nevertheless, adverse environmental impacts like air pollution and water pollution have made this process unpopular.
As solid waste constitutes a low-grade fuel, it has become a tradition in recent years, wherever possible, to recover part of the energy content of waste. The energy recovered can be used for energy requirements of the waste facility itself or for heating or residential, industrial, or commercial power generation. Incinerators and waste-to-energy facilities are more common in urban industrialized areas, largely because of the nature of the urban waste stream; rural waste does not normally have sufficient calorific value to make energy recovery efficient.
Incinerators can be classified by the type and form and waste input, by throughput capacity, by rate of production of heat, by the state in which residue emerges from the combustion chamber, and by the shape and number of furnaces. The key systems involved in incineration are the tipping area, storage pit, equipment for charging the incinerator, combustion chamber, bottom ash removal system, and gas cleaning equipment and boiler, if energy has to be recovered.
The process that takes place inside an incinerator is called pyrolysis, the thermal decomposition of waste at high temperatures in the absence or near absence of oxygen. The products of incineration are in all three forms-solid, liquid, and gaseous. It is important to regulate the temperatures of the furnace depending on the quality of waste so that more hazardous products are not produced upon decomposition and released into the environment.
The impact of emissions from waste incinerators on human health is of great public concern, especially the release of toxins like dioxin. Research has identified numerous toxic compounds emitted in gases and in ashes (e.g., organic pollutants such as chlorinated and brominated dioxins, PCBs and PCNs, heavy metals, sulphur dioxide, and nitrogen dioxide), as well as many unidentified substances of unknown toxicity. This leads to contamination of the environment and to potential exposure of humans to hazardous pollutants that may cause health problems such as cancers.
Besides polluting air, incinerators emit wastes to water from cleaning equipment. While published data on air pollution through emissions from burning waste, fly ash, and bottom ash is available, emissions to water from incineration remain largely understudied. Wastewater from wet exhaust gas cleaning, however, is known to contain heavy metals, the most significant being lead, cadmium, copper, mercury, zinc, and antimony. Wastewater from wet slag removal equipment contains high levels of neutral salts and also contains unburned organic material from the residue. Based on some of this evidence, it can be argued that use of incinerators ignores the adoption of the precautionary principle.
The advantages of incineration include:
- Incinerators can be built close to the source of waste, reducing transport costs.
- Incineration is suitable for many flammable, volatile, toxic, and infectious wastes that should not be land-filled.
- It produces no methane, unlike landfill sites.
- It reduces the amount of waste requiring landfill disposal.
On the other hand, the disadvantages of incineration are:
- High capital and operating costs make it a relatively expensive method of waste disposal.
- Reliance on incineration could restrict choices of future disposal options, including a proper consideration of waste minimization or recycling.
- There is significant danger of atmospheric pollution (though some modern incinerators do meet the strict emission criteria); some incinerators generate toxic liquid effluent.
- The volume of residue is still 40-50 percent of equivalent waste in compacted landfills.
- It concentrates toxic materials in the residue and most residues still have to be land-filled.
The competitive demand for declining fossil fuel supplies has led to the search for energy from renewable sources, including waste. Recovering energy from waste does hold promise for the future, especially with new technologies for emission control that might meet more strict emissions criteria.
Also, it is the basic principle of an ecologicallyoriented waste management policy or waste hierarchy that waste should be reused and recycled. When waste cannot be avoided, recycled, or reused, moreover, it has to be subjected to special treatment before its ultimate disposal to prevent any further environmental burden or impact. One of the most flexible ways to do this is the thermal treatment of unavoidable and unrecoverable residues in modern waste incineration plants equipped with special flue gas cleaning processes. In these plants, the pollutants of the flue gases are eliminated to such an extent that they do not cause any environmental burden.
An example of an incinerator with strict emission control is in Vienna, where an eminent painter was even invited to paint a mural on the incinerator to promote it and increase public awareness of the better emission control system in the incinerator. However, for developing countries, incineration should be used with care.
Although incineration generally reduces the quantity of waste going to landfill sites, it is mainly recommended for medical or hazardous waste in such countries, where resources remain scarce and modern equipment is too expensive to procure for standard waste streams.
- Allsopp, Pat Costner, Paul Johnston, and David Santillo, “Incineration and Human Health: Characterization and Monitoring of Incinerator Releases and their Impact,” in V.I. Grover, V.K. Grover, and W. Hogland, Recovering Energy From Waste (India and Science Publishers, Inc., 2002);
- Ardevol et al., “Environmental Tobacco Smoke Interference in the Assessment of the Health Impact of a Municipal Waste Incinerator on Children Through Urinary Thioether Assay,” Public Health (v.113, 1999);
- Helmut Loffler, “Thermal Treatment of Waste in Vienna: An Ecological Solution?” in V.I. Grover, V.K. Grover, and W. Hogland, Recovering Energy From Waste (India and Science Publishers, , 2002).