The US Department of Environmental Protection has given the go-ahead for the use of real radioactive waste from the Henford facility for the second part of testing of the new technology. At the first stage, their analogue was used, but in the form of a single dose of 11 liters. It was successfully melted into safety borosilicate glass, and now the Ministry wants to check whether the process can be put on stream.
The exact data on the amount of low-level radioactive waste in the United States is classified, but it is known that in the same Hanford complex there are at least 200 thousand cubic meters of waste. The trouble is that, first of all, they are engaged in the disposal of more hazardous high-level waste, so low-level waste has been accumulating for decades. These include all radioactive waste - dirt, dirty water, laboratory items, carcasses of experimental animals, etc.
Before the waste is turned into glass, it is filtered to remove large fragments and particles of heavy metals such as cesium are removed. Then, raw materials for melting glass are added to the semi-liquid mass, after which the mixture is pumped at a strictly defined rate through a 12 cm wide furnace channel.The temperature in it reaches 2149 ° C, the productivity is 227 grams of glass in 30 minutes. The radioactive gases are pumped out and condensed, returning to the smelting mixture.
Borosilicate glass is durable and resistant, radioactive waste in it remains hazardous, but remains "locked up" for thousands of years until the half-life does its job. And such glass ingots still need to be stored somewhere, but it is much safer than liquid waste. The method is not universal, but better than nothing, especially for the United States, where for a long time they preferred to delay the resolution of the disposal issue for bureaucratic reasons.