Using tritium oxide to study moisture transfer in drying phase of mixed dry and wet grain

The internal moisture distribution and process of dry and wet grain moisture transfer in drying phase of mixed dry and wet corn, wheat and rice were studied by using the tritium oxide labelled method. The results show that the drying technology of mixed dry and wet grain has a big range of losing moisture. If the wet grain loses moisture continuously during the whole process, the energy consumption will be reduced. The moisture loss of corn and wheat mainly occurs in those seeds in which the moisture and heat exchange slowly, but for rice it occurs in the heated grains. The process of moisture transfer from inside of the grain to outside shows the direction of moisture gradient is the same with the direction of temperature gradient that is favourable to diffusion of moisture. The study revealed the moisture transfer rule of drying technology and mechanism, and provided a theoretical basis. This technology has advantages of high drying quality and reduction of energy consumption. It provided a new way of drying high moisture grain in northern China