China inaugurated a plant that turns nuclear waste into glass

The first plant opened in Sichuan on September 11 to treat growing amounts of nuclear waste using vitrification.

The plant in Guangyuan in southwestern China's Sichuan province can process several hundred cubic meters of highly radioactive liquid waste each year, according to reports. While China currently has fewer nuclear power plants than France or the United States, the country is rapidly expanding its use of technology to cut carbon emissions.

Quang Nguyen plant has a capacity of handling hundreds of cubic meters of liquid radioactive waste a year. (Photo: Weibo)

The rate of new reactor construction is 7-8 units/year, so waste discharge will become an increasing problem. While some elements such as uranium can be recycled in a reprocessing facility, the remaining spent fuel needs to be disposed of safely. The temporary solution is to grind the waste and mix it with water to store it in metal containers.

However, the above method is still highly radioactive. Nuclear vitrification, which turns waste into glass by heating at high temperatures, is safer in the long term because harmful elements are trapped and stored underground, so it is less of a threat to the environment. than. The idea has existed for a long time, but it is not easy to put it into practice. About 10 vitrification plants established in the past four decades were forced to close due to technical or financial difficulties, according to Chinese researchers.

In the early days, engineers mixed liquid waste with glass-making materials such as silica in a melting pot. But radioactive waste is extremely corrosive at high temperatures and India is the only country to build a plant using this method. Most factories in the US and Europe use innovative technology, such as heating liquids in electric furnaces at temperatures above 1,100 degrees Celsius to form glass with a ceramic coating to protect the metal. Another advantage of the method is that since the glass is present on the outer surface, where the temperature begins to drop, fewer toxic elements escape as a gas. This is the technology applied at Quang Nguyen factory.

In 1999, the prototype system was transferred from Germany to Factory 821, a Chinese military facility in Sichuan specializing in nuclear weapons production with the largest waste storage facility in the southwest, according to an article published by the group. study at the China Institute of Nuclear Energy published last year. But the government had to halt plans to build the plant due to technical problems and high costs. The construction of Quang Nguyen factory was approved by the government in 2009.

Current technology also comes with a number of problems and the team involved in the project is looking for ways to make the process safer and cheaper. For example, electric furnaces need to be replaced at least every five years due to erosion, but the scientists hope to find a way to keep the equipment running by using water to cool the furnace's interior walls. The process creates a thin layer of glass when heated to separate the melted waste from the furnace. The technique was invented by Russian scientists but is not ready for industrial use because of technical challenges.