title: Behaviors of 323Th, 238U, 228Ra and 226Ra on combustion of crude oil terminal sludge.
abstract: Crude oil terminal sludge contains technologically enhanced naturally occurring radionuclides such as (232)Th, (238)U, (228)Ra and (226)Ra, thus cannot be disposed of freely without proper control. The current method of disposal, such as land farming and storing in plastic drums is not recommended because it will have a long-term impact on the environment. Due to its organic nature, there is a move to treat this sludge by thermal methods such as incineration. This study has been carried out to determine the behaviors of (232)Th, (238)U, (228)Ra and (226)Ra present in the sludge during combustion at a certain temperature and time. The percentage of volatilization was found to vary between 2% and 70%, (238)U was the most volatile in comparison with (232)Th, (228)Ra and (226)Ra. (238)U is found to be significantly volatilized above 500 degrees C, and might reach maximum volatilization at above 700 degrees C. A mathematical model was developed to predict the percentage of volatilization of (232)Th, (238)U, (228)Ra and (226)Ra contained in the sludge. With this known percentage of volatilization, the concentration of (232)Th, (238)U, (228)Ra and (226)Ra present in the bottom and filter ashes can be calculated.
authors.affiliation: MIREC, Malaysian Institute of Nuclear Technology for Research (MINT), Bangi, 43000 Kajang, Selangor Dahrul Ehsan, Malaysia. puad@mint.gov.my
authors.forename: H A Mohamad
authors.initials: HA
authors.lastname: Puad
authors.forename: M Y Muhd
authors.initials: MY
authors.lastname: Noor
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D005374:Filtration; D017745:Incineration; D010578:Petroleum; D011868:Radioisotopes / Q000032:analysis*; D012037:Refuse Disposal; D012767:Ships; D014835:Volatilization
chemical_list: D000396:Air Pollutants, Radioactive; D010578:Petroleum; D011868:Radioisotopes