Energy

China adding finishing touches to world-first thorium nuclear reactor

China adding finishing touches...
China is pursuing an experimental form of nuclear fission in thorium molten salt reactors, and will reportedly begin tests at a facility in the coming months
China is pursuing an experimental form of nuclear fission in thorium molten salt reactors, and will reportedly begin tests at a facility in the coming months
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China is pursuing an experimental form of nuclear fission in thorium molten salt reactors, and will reportedly begin tests at a facility in the coming months
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China is pursuing an experimental form of nuclear fission in thorium molten salt reactors, and will reportedly begin tests at a facility in the coming months

China is moving ahead with development of an experimental reactor that would be the first of its kind in the world, but could prove key to the pursuit of clean and safe nuclear power. According to local news reports, the Chinese government intends to finish building a prototype molten salt nuclear reactor in the desert city of Wuwei in the coming months, with plans to establish a number of larger-scale plants in similar settings thereafter.

With an ability to generate power while producing very minimal carbon emissions, nuclear reactors have a clear upside when it comes to the sustainable generation of energy. But there are very valid reasons the technology hasn't been widely adopted across the world, many of which stem from the reliance on uranium and plutonium for fuel.

Not only is uranium expensive and rare, it can also be used to build nuclear weapons. These reactors also generate radioactive waste that needs to be safely stored, and carry the very real risk of catastrophic meltdown, as seen at Fukushima in 2011.

Since the 1940s, scientists have been exploring an alternative known as molten salt reactors, which promise a far safer way forward. In place of uranium and plutonium, these reactors use the widely abundant, silvery metal thorium, which cannot be easily used to make bombs. Furthermore, these reactors would operate in a way that doesn't pose the same dangers as conventional ones.

This is because instead of solid fuel rods, thorium is dissolved in molten salt that is flowed through the reactor at high temperature. In this form the liquid salt acts as a coolant and there is no need for high-pressure water cooling systems, and if there is an accident and the fuel is exposed to air, it quickly cools and turns solid. Compared to a conventional nuclear reactor that can quickly cloud vast areas in radioactive material, this significantly limits the potential contamination of the surrounding environment.

Despite its promise, advancing the technology behind molten salt reactors has been slow going. Experiments were carried out in the US in the 60s and 70s, and then in Asia and Europe. More recently, we saw a research group in the Netherlands kick off experiments aimed at turning the technology into an industrial-scale source of energy.

In recent times, China has been leading the charge. In 2011, its government approved plans for a thorium molten salt reactor in the desert city of Wuwei, in the province of Gansu, and tasked its scientists with developing the technology to run it. Now, as reported by the South China Morning Post, construction on the two-megawatt prototype reactor is due to wrap up next month and the first tests could begin as soon as September.

If these plans are realized, the facility would become the first operational thorium molten salt reactor anywhere in the world. Government scientists hope to use it as a springboard for the development of larger thorium molten salt reactors that generate up to 100 MW, which are planned for several other desert locations and could each provide enough power for 100,000 inhabitants. Construction on the first commercial reactor is expected to be complete by 2030.

The plans are grand but the fine details remain light on, particularly relating to the technical obstacles that have plagued the technology in the past. One major issue molten salt reactors have to contend with is corrosion, with the radioactive molten salt prone to eating away at piping or other components.

Another relates to the processes that drive the generation of energy. Conventional nuclear reactors are able to split atoms of uranium in a way that results in a chain reaction and continual energy production, whereas thorium doesn't contain enough fissile material to do this all on its own. This means it needs to be mixed with uranium anyway, or another material that help trigger the necessary reactions.

This means that a thorium nuclear reactor has never been proven on a commercial scale before, and plenty have doubts that one ever will be. In any case, China's scientists have been spearheading research and development in the area since the project kicked off a decade ago, so perhaps they are finally ready to show their hand.

Source: South China Morning Post

17 comments
17 comments
FB36
"Not only is uranium expensive and rare, it can also be used to build nuclear weapons. These reactors also generate radioactive waste that needs to be safely stored"

Nuclear waste problem only exists today because some people prevented construction of kind of nuclear reactors, which can use spent fuel from others as fuel, by claiming that would cause nuclear proliferation! However, the real world evidence clearly shows that not constructing such reactors never actually prevents any willing countries (like N Korea & Iran) from nuclear proliferation!
jerryd
Building one and making it work are completely different things. And China's recent history on nukes is not good.
techmanmacho
Not the World's first Thorium Reactor. The Oak Ridge National Laboratory operated an experimental Thorium Reactor for 15,000 hours from 1965 to 1969. https://en.wikipedia.org/wiki/Thorium-based_nuclear_power
Expanded Viewpoint
Someone needs to sit down and do an energy audit on this before going one step more. Back in about 1998, an energy audit was done on the nuclear power industry, and it was determined that the amount of carbon based fuels burned in mining and processing Uranium ore into fuel, etc, was MORE than what would have been needed to generate the same amount of electricity in a regular steam plant, if it had just been burned there instead!! What then, was the point of building nuclear power plants?? Here we go again, spending 50 dollars to generate 20 dollars' worth of electricity!
NMBill
Another case in which the US could have and should have been a generation ahead of the Chinese in this technology. Absent a reliable, robust, affordable grid-scale energy storage solution, clean nuclear is by far the best, most viable alternative to carbon-based energy for base load power.
SIGMA3572-gizmo@YAHOO.COM
Reply to Expanded Viewpoint -Thorium comes from waste products of mining. Thorium is estimated to be over three times as abundant as uranium in the Earth's crust and is chiefly refined from monazite sands as a by-product of extracting rare-earth metals.
aksdad
As FB36 points out, nuclear waste from uranium-fuel reactors can be reprocessed and re-used to extract even more energy from current reactors. Other reactor designs can reduce the high-level nuclear so it has a relatively short half-life on the order of hundreds of years. The amount of waste generated is miniscule, even from current reactors. All the burnt reactor cores from all the reactors in the U.S. since the 1950's would fit in a football field, stacked several feet high. Producing energy from uranium is so efficient that only small amounts are needed. Now that uranium extraction from seawater has been proved practical and economical, there is enough uranium diluted in seawater to provide all the energy needs of humans for a billion years. For all practical purposes, that's "sustainable". Uranium only needs to be enriched to 3 to 5 percent for reactor fuel, far below the amount (20% or higher) that can be used for a weapon. New reactor designs are far safer than previous generations, which were already so safe that nuclear power accidents have resulted in far fewer deaths (dozens) than any other base load power production technology (hundreds to thousands).
TechGazer
Regarding the energy cost of processing uranium, I think most of it is consumed in isotopic separation, not necessary for thorium.

For me, molten salt reactors, particularly using thorium, sound like a good idea, but build one, operate it for a suitable period of time, and then do a proper audit to see if it really is a good idea. There are too many unknowns to start mass-producing them.
Jinpa
Dr. Arjun Makhijani is not a fan or thorium reactors. Read his articles at: https://ieer.org/resources/subject-index/ Use your Edit/find function to find the relevant articles.
There is a Wikipedia article on thorium reactors. Safe nuclear and clean coal are oxymorons. Read the book Insurmountable Risks, by Brice Smith.
Eric Robinson
"One major issue molten salt reactors have to contend with is corrosion, with the radioactive molten salt prone to eating away at piping or other components." - this was solved by, corrosive resistant, Hastelloy-N in the 1960s Molten Salt Reactor Experiment that ran for 5 years at Oak Ridge National Labs, Knoxville TN.