The performance of clay at different moisture contents for environmental protection against gamma ray

In recent years the application of nuclear energy increases in various fields. However, radiation more than the standard limit can impose very bad effects on human and environmental health. So, radiation shielding becomes a very important issue. Clay soil is natural, eco-friendly and inexpensive material. In this research the performance of bentonite clay soil with different moisture contents in radiation shielding about Gamma ray at three level of energy (661.6, 1173.2 and 1332.5 keV) were investigated. At first plastic and liquid limit moisture contents were obtained by means of Atterberg limits test. Then samples at three state (dry, plastic and liquid limit moisture contents) were made. Radiation shielding parameters such as linear attenuation coefficient (µ), HVl and TVL were measured by HPGe detector. The microstructure of the bentonite was characterized by Scanning Electron Microscope (SEM) with Energy Dispersive X-ray (EDX). Results of bentonite samples were compared with concrete linear attenuation coefficient. Result indicated that bentonite at plastic limit moisture content have good performance in radiation shielding. So bentonite clay at plastic limit moisture content can be used for radiation shielding in many cases such as cap and around of low level radioactive waste disposal.

Keywords:

Environmental protection , Gamma-ray Shielding , Bentonite clay , moisture content , low level nuclear waste disposal