哈尔滨燃煤电厂周围土壤放射性水平的分析

煤炭燃烧过程中,放射性核素会不同程度的在飞灰和炉渣中富集,进而随着飞灰和炉渣进入土壤环境中,对土壤造成不同程度的放射性污染。本文以哈尔滨群力燃煤电厂和呼兰燃煤电厂为研究对象,在距电厂1 km范围内布设采样点,每个采样点土壤分3层采样,即A层深度:0～10 cm,B层深度:10～20 cm,C层深度:20～30 cm。利用高纯锗γ谱仪测量土样中的天然放射性核素,分析了燃煤电厂周围土壤样品中²³⁸U、²³²Th、²²⁶Ra、⁴⁰K的含量,并与黑龙江省土壤天然放射性核素测量结果进行了比较。结果表明,在群力电厂和呼兰电厂1 km范围内周围土壤中,除了天然放射性核素²³⁸U以外,其他3种核素含量都未超出全省含量最大值,其中核素²³²Th的含量甚至低于全省大部分地区;燃煤电厂的长期运行给土壤环境带来了一定的放射性影响,土壤本底的放射性核素含量发生了一些变化,这种变化在呼兰电厂周围的土壤中表现得更为明显,但是并未超出国家规定的标准,污染程度在可接受的范围内。

Analysis of radiation level in soil around coal-fired power plants in Harbin

Radionuclides can accumulate in fly ash and slag in the process of coal burning at different levels and fall into the soil resulting in radioactive contamination. The sampling points were located within 1 km to the Qunli and Hulan coal-fired power plants, and each sampling point was divided into three layers of different depth: A layer for 0—10 cm, B layer for 10—20 cm, and C layer for 20—30 cm. The natural radionuclides in soil samples were measured by high-purity germanium gamma spectrometer, and the specific activities of ²³⁸U, ²³²Th, ²²⁶Ra and ⁴⁰K in the soil surrounding the coal-fired power plants were analyzed and compared with the measurement results of natural radionuclides in soils from the Heilongjiang province. Results showed that the long-term operation of the coal-fired power plants has increased the radiation levels, but it is still below the national standards.