The problem of energy is a problem that mankind has had to face for centuries. Compared to traditional sources of energy such as fossil fuels, solar energy, wind energy and water energy, nuclear energy has drawn increasing attention because of its high concentration of energy and minimal amount of waste. However, the waste generated from the production of nuclear energy is highly radioactive, but in order to extract valuable energy from uranium and plutonium, we have to reprocess nuclear fuel (fuel elements no longer usable and removed from reactor) generated at nuclear power stations.
The Institute of Nuclear and New Energy Technology of Tsinghua is located in the northwestern suburbs of Beijing. The entire park sits on a hillside with evergreen pines, quietly hidden. The Laboratory of Nuclear Chemistry and Nuclear Chemical Engineering was built in the 1960s. Its earliest use was to provide weapons-grade plutonium for China. At present, its main research directions are to improve the solvent extraction method, improve high-temperature reactor related technology, nuclear fuel cycle and nuclear pore membrane technology.
In a short morning, Director Wang of the Lab took me along to visit the radiochemical laboratory, radiochemical technology laboratory, liquid measurement flash chamber, dry chemical laboratory, chemical laboratory, and the organic synthesis room. He also showed me experiment equipments and instruments such as fume hood, centrifugal extractor, old mechanical scale, hand and foot detector, hand calculator, simulated liquid water tank, mixed clarification tank, pulse extraction column, and extractant synthesis device. I have to admit that, due to decay over time, the room’s lighting conditions are generally poor, and many equipments are covered under a layer of dust. However, Director Wang reminds me of the history of the laboratory: the development of nuclear fuel reprocessing technology has a long past.
In the 1950s, the former Soviet Union promised China to build a reprocessing plant, which provided a backward precipitation method with low yield and poor separation effect. It is difficult for units within the state nuclear industry department to implement this method. At the same time, faculty and students from Tsinghua’s Department of Engineering Physics chose the most advanced tributyl phosphate solvent extraction method as their main research direction. In 1964, China’s central government approved the construction of a thermochemical laboratory at Tsinghua No. 200 site to prove the feasibility of the extraction method.
In 1966, upon the completion of the thermal experimental research, the central government decided to adopt the extraction method to build factories, which greatly enhanced China’s post-industrial technology. In 1970, nation-states began signing a nuclear non-proliferation treaty. In the late 1970s, the trialkyl phosphine oxide extraction method was invented. Through years of research, a process with high separation efficiency called TRPO was completed for using high-level liquid waste.
Strong wind lifts the autumn leaves onto a path. The No. 200 site is tranquil showered with the beauty of a warm golden sunlight. The lonely building had left behind green leaves and a gray wall, and the structure reminds me of Tsinghua’s distant past. When I left the the Institute of Nuclear and New Energy Technology, a wave of emotions surged within my heart - under the yellowed memories are buried stories of hardship and bravery, an authentic portrayal of our predecessors’ lives. We should not forget this place though it is far from Tsinghua campus.