²¹⁰Po distribution after high temperature processes in coal-fired power plants

Area of Science:

• Environmental Science
• Radiochemistry
• Industrial Ecology

Background:

• Coal-fired power plants (CFPs) are significant sources of airborne pollutants.
• Polonium-210 (²¹⁰Po) is a naturally occurring radioactive isotope present in coal.
• Understanding ²¹⁰Po distribution is crucial for assessing radiological impacts from CFPs.

Purpose of the Study:

• To evaluate the distribution and behavior of ²¹⁰Po in various output streams of coal-fired power plants.
• To quantify the fraction of ²¹⁰Po released into the environment via flue gases.
• To provide data for environmental radiological risk assessments related to CFPs.

Main Methods:

• Sampling of coal, bottom ash, fly ash from electrostatic precipitators (ESPs), and flue gases from four CFPs.
• Radiochemical analysis to determine ²¹⁰Po content in all sampled materials.
• Mass balance analysis to track ²¹⁰Po through the combustion process.

Main Results:

• ²¹⁰Po is predominantly captured by ESPs, with minimal amounts in bottom ash.
• Flue gas emissions account for 0.06%-0.6% of the total ²¹⁰Po, aligning with existing literature.
• An unaccounted fraction of ²¹⁰Po was observed in the mass balance, consistent with previous studies.

Conclusions:

• The electrostatic precipitator is highly effective in capturing ²¹⁰Po from coal combustion.
• Direct environmental discharge of ²¹⁰Po from CFPs is relatively low but requires monitoring.
• The study provides essential data for refining environmental radiological risk assessments for CFPs.