On 9th October, with control rod slowly rising, China's first lead-bismuth alloy zero-power reactor – Qiminxing (Venus) III - achieved first criticality in China Institute of Atomic Energy (CIAE). Core physics experiments are subsequently started.  The milestone marks that China's research and development in the field of lead-bismuth fast reactor has taken a substantial step and entered the engineering stage from the physical basic research stage. China is now one of the leading countries in this field.

Technicians bring the Venus III reactor to first criticality (Image: CIAE)

Venus series zero- power reactor is the only important reactor physical experiment platform in China for the development of advanced reactor engineering technology, which is designed and built by CNNC.

Aiming at the key and difficult problems in the engineering of a lead-bismuth fast reactor, it took almost two years to complete. The interaction mode of nuclear fuel and lead-bismuth alloy coolant material is accurately constructed in large-size lead-bismuth alloy coolant material, and the core physical properties of a lead-bismuth reactor are more accurately simulated.

In July 2005, China's first fast thermal-coupled Accelerator Driven System (ADS) sub-critical reactor - Venus I - was built at CIAE and reached criticality. In December 2016, China's first lead-based double-core zero-power device - Venus II - achieved first criticality at CIAE.

It is reported that the CIAE has been committed to the development of liquid metal cooled fast reactor technology including sodium cooled fast reactor for decades. Among which the self-developed small lead-bismuth fast reactor is ready for engineering realization.

After criticality of Venus III, A series of experiments will be conducted. Core nuclear parameters will be obtained not only for the macro inspection of basic nuclear design data of all types of lead bismuth reactors, but also for the comprehensive verification of core design and safety analysis methods. It will further contributed to the innovative research and development of advanced nuclear technology.