Experimental Study on Preheated Air and Flue Gas Recirculation in Solid Waste Incineration (original) (raw)
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Waste-to-energy (WtE) incineration is an important technique in waste management systems and waste hierarchy. It is used to treat approximately 63% of the waste in European countries. The flue gas volumetric rate and its composition are essential to determine and monitor the emissions from waste incineration plants. This paper presents two methodologies used to evaluate the emissions from incinerators during the design phase. The first consists of a set of equations applicable in Excel (calculation model), while the second is the built-in components in Ebsilon 13.2 software which simulates the emissions from a furnace. This paper also proposes a comprehensive flue gas cleaning system for a simulated waste incineration plant in Jordan. According to Ebsilon, the results showed that for a 25 kg/s loading rate, there was 258,514 mg/Nm3, 749.90 mg/Nm3, 890.20 mg/Nm3, and 717 mg/Nm3 of CO2, NO2, SO2, and HCL, respectively. It was noted that these values relate to 1.5 of excess air ratio, ...
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Waste and Biomass Valorization, 2014
The first objective of any waste policy should be to minimize the negative effects of the generation and management of waste on human health and the environment. Re-use and recycling of waste, although of high priority in the waste hierarchy, is not necessarily always the best treatment method. In the case of hazardous waste containing toxic components, thermal treatment with energy recovery constitutes a cost effective treatment option, complying with the pillars of ''Sustainability'' and the requirements of ''Resource Efficient and Cleaner Production''. Iron recovery from the incineration ashes, water recycling, substitution of fossil fuel by high calorific waste in the incineration process, and energy recovery, avoid the use of non-renewable resources. Emissions to air and discharges to water of a typical rotary kiln for the incineration of hazardous waste, are far below the European emission limit values. Furthermore, recent studies on health effects of modern, state-of-the art waste incinerators show that any potential damage to the health of those living close-by or working in a hazardous waste incineration plant, is likely to be very small, if detectable.
Environmental impact of emissions from incineration plants in comparison to typical heating systems
E3S Web of Conferences
In recent years, five modern municipal waste incineration plants have been built in Poland. Next ones are being constructed and at the same time building of several others is being considered. Despite positive experience with the operation of the existing installations, each project of building a new incinerator raises a lot of emotions and social protests. The main argument against construction of an incineration plant is the emission of pollutants. The work compares emissions from municipal waste incineration plants with those from typical heating plants: in the first part, for comparison large heating plants equipped with pulverized coal-fired boilers (OP-140), stoker-fired boilers (three OR-32 boilers) or gas blocks with heat output of about 100 MW have been selected, while the second part compares WR-10 and WR-25 stoker-fired boilers most popular in our heating industry with thermal treatment systems for municipal waste or refuse-derived-fuel (RDF) with similar heat output. Bot...