Akademik Veri Yönetim Sistemi
V. International Ege Composite Materials Symposium 2021, Antalya, Türkiye, 4 - 06 Kasım 2021, ss.420
Fly ash produced by combustion of coal for energy production contains naturally occurring radionuclides
such as 238U, 232Th and 40K and toxic elements such as Cd, Cr, Cu, Ni and Pb. These radionuclides and
trace elements become enriched in ash fractions during the combustion process of coal-fired thermal power
plants. There is a growing tendency of recycling industrial by-products such as coal fly ash in order to
prevent environmental pollution. These by-products may potentially be recycled as building materials such
as cement, concrete, bricks and road construction materials. However, prior to use, these materials must be
screened for potantial radiological and toxic impact as specified by various international regulations. For
example, the European Basic Safety Standards identifies the Activity Index (ACI), determined from
measured natural radionuclide concentrations, as a screening metric. 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 Seyitömer coal-fired thermal power plant, namely the water pre-heater (economizer), air
preheater (LUVO), three rows of the electrostatic precipitators (ESP) and chimney stack. Trace element
concentrations and natural radionuclides were determined via inductively coupled plasma (ICP-OES) and
gamma spectrometry, respectively. Further, leaching tests were conducted on fly ash samples to measure
heavy metal mobility into the environment. 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 recyling into secondary raw materials and any necessary mixing or
dillution that must occure prior to use. This information will help the energy industry develop sustainable
solutions to waste disposal. This work also uses the heavy metal concentration and leaching test results to
determine the Potential Ecological Risk Index (PERI) to examine potential toxic metal diffusion into the
environment. Acknowledgments: This work was supported by grants from The Scientific Research
Committee of Ege University, Contract No:FGA-2020-21865.