Fifth International Conference on Natural Resources and Sustainable Environmental Management, 8 - 12 November 2021, pp.1
. Coal-fired power plants are widely used worldwide in order to generate electricity. Coal, residues and waste produced by combustion contain naturally occurring radionuclides such as 238U, 226Ra, 232Th and 40K and trace elements such as Cd, Cr, Pb, Ni and Zn. These radionuclides and trace elements become enriched in ash fractions during combustion. During high temperature processes in the furnace, volatile and semi-volatile elements and radionuclides are partially emitted to the environment, depending on their chemical form in the original fuel, the technological set-up of the combustion system, and the prevailing combustion conditions. In recent years, there is a growing tendency to utilize coal fly ash as an industrial by-product in order to prevent environmental pollution. Utilization of coal fly ash in the construction industry has clear environmental and economic advantages. However, prior to use, these materials must be screened for potential radiological and toxic impact as specified by various international regulations. For example, the European Basic Safety Standards specifies the Activity Index (ACI) as a screening metric for materials prior to use.
This work determines
the potential radiological and toxic impact of all fly ash types collected at
different stages along the emission control system of the Yatagan, Yeniköy and Seyitömer
coal-fired thermal power plants, namely the water pre-heater (economizer), air
preheater (LUVO), and three rows of the electrostatic precipitators (ESP). ACI
metrics for all fly ash materials were calculated from the natural radionuclide
concentrations. This work then uses these ACI metrics as a basis for
recommending which waste streams are suitable for recycling into secondary raw
materials and any necessary mixing or dilution that must occur prior to use.
This information will help the energy industry develop sustainable solutions to