Thorium: A kind of clean energy resource for “dual carbon” goals

Thorium is a kind of radioactive element of multiple industrial uses. Due to China’s “dual carbon” goals, it attracts lots of attention in recent years because of its cleaner and more effective performance than uranium in nuclear power reactors. However, the distribution of thorium ore resources is uneven, as well as that of thorium (including concentrates, metal, and compounds) production and consumption. As a result, it is necessary to analyzes the state of thorium in detail globally based on the resource-economy-environment system. The method of material flow analysis is applied in this paper in order to unveil the characteristics of Thorium flow in the resource-economy-environment system. The distribution, genetic types, and exploration status of thorium deposits in the world and China are summarized respectively based on the analysis of statistics of thorium deposits exploration, industrial production, and international trade. The conclusions of this paper indicate that the abundant thorium resources, with placer type as the main genetic type, are centralized distributed in India, Brazil, the US, etc. However, carbonite type, alkaline type, and veins type are the main genetic types of thorium in China with an uncertain quantity. In the resource-economy-environment system, global thorium outputs decreased during 2010—2017 followed by a significant increase after 2018, of which the main source is the byproduct of monazite mining and concentrating. Thorium and its compounds are used in the field of energy, material, metallurgy, and medicine, while thorium emission is only associated with the mine and concentration of ores. Based on the analysis of thorium applications, it is supposed that the thorium output may continue increasing in the coming decade as a result of the growing uses of thorium in nuclear power reactors. It is necessary to carry out enough exploration on thorium in order to figure out the thorium resources in China because of the difference in genetic types between China and abroad. In order to achieve the aim of carbon peak and carbon neutralization, the government should carry out a series of policies to encourage the innovation and popularization of new techniques to improve thorium utilization and protect the environment.