Natural radionuclides in fuel and waste from Danish power plants

摘要

We have examined the content of natural occurring radionuclides in three types of fuel and waste from power plants in Eastern Denmark (coal, orimulsion and biomass). While coal previously was the main fuel used for power production, the majority of fuel used today is biomass, natural gas and orimulsion. Coal was in 2000 less than 50 %. It was found that the Ra-226 content of coal ash was on an average 104 Bq/kg, which is similar to what was found in previous studies. The Ra-226 content of orimulsion ash is only 8 Bq/kg, which exclude radiological problems with this fuel and the associated ash. Bio fly ash from combustion of straw contains about 40 % potassium and from a radiological point the K-40 content of up to 13000 Bq/kg is the most interesting. However, even handling of large amounts of bio fly ash will probably not give external doses to workers beyond the radiological protection goals of the European Basic Safety Standards.