Ambient Decontamination of Nuclear Reactor Surfaces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current radioactive decontamination methods for nuclear power plant components require high temperatures, aggressive chemical conditions, and generate significant radioactive waste, making them cumbersome and unsafe for routine use in nuclear reactors.
Innovation Solution
A method involving an aqueous solution with elemental metals like zinc, added at ambient temperature, to disrupt and dissolve radioactive deposits on reactor surfaces, using electrochemical techniques without the need for elevated temperatures or external heat, and employing sequestering agents to precipitate and remove radionuclides.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high temperature processes are used to remove radionuclides, then decontamination effectiveness is improved, but energy consumption and system complexity increase
Solution Approach 1:
The patent changes the temperature parameter from high temperature to ambient temperature operation. The decontamination process uses elemental metals in aqueous solutions at ambient temperature to disrupt radionuclide lattices, eliminating the need for thermal energy input while maintaining effective radionuclide removal through electrochemical reactions
Solution Approach 2:
The patent replaces thermal/heat-based decontamination systems with electrochemical systems using elemental metals. Instead of using heat to dissolve or remove radionuclides, the invention uses electrochemical reactions where elemental metals (such as zinc, aluminum, or magnesium) react with radionuclide-containing oxides, substituting a chemical/electrochemical mechanism for a thermal one
2Reliability
If aggressive chemical conditions are used to remove radionuclides, then decontamination effectiveness is improved, but harmful factors and waste generation increase
Solution Approach 1:
The patent converts the harmful radionuclide deposits into a beneficial form by using elemental metals to reduce radionuclides from their oxidized, lattice-bound state to metallic or soluble forms that can be easily removed. The aggressive chemical action is directed at transforming the harmful radionuclide structure into removable forms, and the resulting waste is minimized because the process occurs at ambient temperature with less aggressive chemistry
Solution Approach 2:
The patent uses inexpensive, readily available elemental metals (zinc, aluminum, magnesium) as disposable reagents that react with and remove radionuclides. These cheap metals serve as sacrificial agents that can be easily replaced, and their use at ambient temperature reduces the generation of harmful waste compared to high-temperature processes
3Reliability
If multiple chemical steps are used to remove radionuclides, then decontamination effectiveness is improved, but device complexity and operational difficulty increase
Solution Approach 1:
The patent merges multiple chemical steps (oxidation, reduction, dissolution) into a single integrated process. Elemental metals in aqueous solution simultaneously perform reduction of radionuclides and dissolution of oxide scales in one step, eliminating the need for separate oxidation and reduction stages required by conventional methods
Solution Approach 2:
The elemental metals serve multiple functions simultaneously: they act as reducing agents to disrupt radionuclide lattices, as chelating agents to solubilize metal ions, and as sacrificial anodes to prevent re-oxidation. This multi-functionality simplifies the overall process compared to conventional methods that require separate specialized steps for each function
4Reliability
If high temperature fluids are used for decontamination, then radionuclide removal is improved, but safety risks and operational hazards increase
Solution Approach 1:
The patent inverts the conventional approach by using ambient temperature instead of high temperature, and elemental metals instead of aggressive chemical reagents. This inversion maintains radionuclide removal effectiveness while eliminating the safety hazards associated with handling hot fluids and aggressive chemicals
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method effectively reduces radioactive deposits at ambient temperature, minimizing waste generation and operational disruptions, while maintaining system integrity and safety by destabilizing radionuclide lattices and facilitating their removal without aggressive chemical conditions.
Implementation Method 1
adding an effective amount of an elemental metal in solid form to the aqueous solution. The method is conducted at ambient temperature.
Implementation Method 2
contacting the surface of the structure with an aqueous solution
Implementation Method 3
employing sequestering agents to precipitate and remove radionuclides
Data Source
AI summary
A method for at least partially disrupting or removing radioactive deposits formed on a surface of a structure in a nuclear water reactor is disclosed. The method includes identifying the structure, taking the structure out of operational service, isolating the structure, contacting the surface of the structure with an aqueous solution, and adding an effective amount of an elemental metal in solid form to the aqueous solution. The effective amount includes an amount to at least partially disrupt or remove the radioactive deposits formed on the surface of the structure. The method is conducted at ambient temperature. The radioactive deposits include oxide-containing radionuclides deposited on the surface. The surface is a primary side structure in the nuclear water reactor.