某市两座地下水处理厂氡浓度初步调查与分析

目的 通过对水和空气中氡浓度的测量,初步调查水氡释放对水厂空气氡的影响.方法 选取某市的两座地下水处理厂,采集水厂的水源水、出厂水和末梢水.利用连续测氡仪快速水氡测量方法,测量水中氡浓度;采用固体径迹探测器,累积测量水厂不同区域空气氡浓度.结果 两座水处理厂水源水、出厂水和末梢水中氡浓度分别为:(7.59±1.36)、(3.56±0.86)和(3.68±0.81)Bq/L与(12.19±0.57)、(7.87±1.12)和(9.50±1.12)Bq/L.水源水最高,出厂水与末梢水相近.跌水曝气和开放式过滤工艺能明显降低水中氡含量.曝气室和过滤车间氡浓度分别高达4 218和1 937 Bq/m³,明显高于我国工作场所氡浓度限值1 000 Bq/m³.结论 地下水处理厂曝气车间和开放式过滤车间氡浓度受到水氡释放的影响,我国地下水处理厂氡的问题应该引起重视.

Investigation and analysis of radon concentrations in two groundwater supplies in a city

Objective To explore the effect of radon released from water on the indoor radon activity concentration in groundwater supplies. Methods Two groundwater supplies in a city were chosen. Radon concentrations in three kinds of water samples were determined by using a continuous radon monitor with air-water exchanger, including source water, finished water and tap water. The solid track detector was used to analyze the indoor radon concentration in water supplies. Results The concentrations of radon in source water, finished water and tap water were (7.59±1.36), (3.56±0.86), (3.68±0.81)Bq/L and (12.19±0.57), (7.87±1.12), (9.50±1.12)Bq/L, respectively. The concentration of radon was the highest in source water and at less varying level in finished water and tap water. Aeration and filtration tank process significantly decreased radon activity in water. Radon concentrations in aeration and filtration rooms were 4 218 Bq/m³ and 1 937 Bq/m³, respectively, which exceeded the limit in work place (1 000 Bq/m³). Conclusions Aeration and filtration workplaces for groundwater supplies were found to contain elevated radon concentrations in air, which was released from groundwater. Radon issues in groundwater supplies in China should be paid more attention.