Though many countries started to use renewable energy sources, still there are currently 437 operable civil nuclear power nuclear reactors around the world. Nuclear wastes are a significant part of the nuclear power picture, and need to be managed and disposed of properly.
Do we still need nuclear power?
Though in more than 50 decades of civil nuclear power experience the wastes have not caused serious health problems, nor posed any real risks to people, the fear of the civilians has to be taken very seriously. Many states use alternatives for power generations, but they are not without challenges, either financially or technically.
Protect people and environment
The main objective in managing and disposing of radioactive waste is to protect people and the environment. This means isolating or diluting the waste so that the rate or concentration of any radionuclides returned to the biosphere is harmless. To achieve this, practically all wastes are contained and managed – some clearly need deep and permanent burial.
One of the first radioactive waste repositories in the world
The facility at Bataapati (LILW) is one of the first radioactive waste repositories in the world. After 15 years of work and an investment of $310 million, the first disposal chamber at Bataapati in southern Hungary has now been completed.
Sprayed concrete, full site support and trainings
From past experiences in those difficult fields, Sika was selected to provide the comprehensive support and sprayed concrete solutions for this project, including full compliance with the latest EFNARC standards and regulations. This required detailed site inspection services and the fresh concrete checks and monitoring, together with full site support for the sprayed concrete machinery and equipment, plus all of the necessary training of the people operating the nozzles and other key operators throughout the works.
Chambers get sealed with a mixture of clay and concrete with crushed granite
The Bataapati facility will eventually allow the disposal of some 40,000 m3 of radioactive waste. The first disposal chamber can accommodate 4,600 drums of waste contained in 510 reinforced concrete containers. The disposal chambers are located in pairs contained in 3 underground caverns excavated 200 - 250 m deep within the granite bedrock. The chambers will then be sealed and backfilled with a mixture of clay and concrete with 50-60% crushed granite.
The construction support
Shotcrete was used to stabilize the excavation like in common tunneling or mining. Sika supplied a powerful package of shotcrete products like Sika® ViscoCrete®SC®305, superplasticiser for sprayed concrete or SikaFume®, silica fume additive amongst other products.
Water is the reliable shield
In practice, the spent fuel is never unshielded. It is kept underwater as water is an excellent shield for a few years until the radiation decays to levels that can be shielded by concrete in large storage casks. Options include deep geologic storage and recycling. The sun would consume it nicely if we could get into space, but since rockets are so unreliable, we can’t afford to risk atmospheric dispersal on lift-off.