NGHIÊN CỨU XÁC ĐỊNH TỔNG HOẠT ĐỘ PHÓNG XẠ ALPHA, BETA TRONG CÁC MẪU NƯỚC THẢI ĐÃ XỬ LÝ TỪ QUÁ TRÌNH CHẾ BIẾN CÁC LOẠI QUẶNG SA KHOÁNG

Tóm tắt

The determination of gross alpha and beta activities in waters with the low dissolved solid materials
can be easily done. However, for the treatment of liquid wastes containing high radioactivity from the beach
sand mineral processing, a large amount of chemicals have been introduced to form soluble salts, which are
mainly NaCl, that contributes to the decrease in performance, and in sensitivity of the measurement,
resulting in the inaccurate or even impossible determination of the gross alpha and beta activities. The
method of separating radioactive elements from the interfering salt background by co-precipitation using
BaRa(SO4)2, and Fe(OH)3 was performed in this paper. The study was carried out on treated waste samples
from the beach sand mineral processing. The results showed that the efficiency of the radioactive elements
separation when the alpha activity was from 3.5 Bq/L and the beta from 2 Bq/L reached up to 95% and then
we could easily determine the gross alpha and beta radioactivity in the separated fractions with high
stability and accuracy. Limit of detection with alpha and beta for treated waste water from the beach sand
mineral processing was 0.0074 Bq/L and 0.021 Bq/L, respectively.