Nuclear Depressurization Filter Preheating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current systems for pressure relief in nuclear power plants fail to effectively retain organoiodine compounds during accidents, leading to potential radiation exposure and operational inefficiencies due to the destruction of sorbent filters under high temperatures and moisture conditions.
Innovation Solution
A method involving overheating the relief flow by direct or indirect heat transfer from the high-pressure section to a temperature at least 10°C above the dew point temperature before it enters the sorbent filter, preventing condensation and enhancing iodine retention, while eliminating the need for external energy sources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the relief flow is passed through a sorbent filter under high temperature and moisture conditions, then iodine retention is improved, but the filter surfaces are destroyed or clogged
Solution Approach 1:
The relief flow is preheated in the high-pressure section before entering the sorbent filter to ensure the filter temperature remains above the dew point. This preliminary heating action prevents moisture condensation on the filter surfaces, avoiding destruction and clogging while maintaining iodine retention capability
Solution Approach 2:
The system provides thermal cushioning to the sorbent filter by continuously heating it with the high-pressure relief flow. This beforehand cushioning against temperature drops prevents the harmful effect of moisture condensation, protecting the filter surfaces from destruction and irreversible clogging
2Strength
If external heating devices are used to prevent condensation in the filter chamber, then filter protection is improved, but device complexity and energy consumption increase
Solution Approach 1:
The high-pressure relief flow serves its own purpose of preventing condensation by using its own thermal energy to heat the filter chamber. This self-service approach eliminates the need for external heating devices, reducing system complexity and energy consumption while maintaining filter protection
Solution Approach 2:
The high-pressure relief flow performs multiple functions: it provides pressure relief, heats itself to maintain temperature, and simultaneously heats the filter chamber to prevent condensation. This multi-functionality eliminates the need for separate heating systems, reducing device complexity
3Object-affected harmful factors
If the relief flow is expanded and cooled before filtration, then moisture condensation is reduced, but iodine retention efficiency decreases
Solution Approach 1:
The relief flow is preheated in the high-pressure section before expansion and filtration. This preliminary heating ensures that even after expansion, the temperature remains above the dew point, preventing moisture condensation while maintaining conditions favorable for iodine retention in the sorbent filter
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 approach achieves high iodine retention rates (>99.99%) and extends filter lifespan, ensuring effective pressure relief and containment safety without external energy, even under adverse conditions.
Implementation Method 1
the relief flow is heated by heat transfer from the not yet expanded relief flow in the high-pressure section
Implementation Method 2
the relief flow is first conducted in a high-pressure section, then expanded by expansion at a throttle device, then at least partially passed through the filter chamber
Implementation Method 3
expanded by expansion at a throttle device
Implementation Method 4
an intermediate sorbent filter comprises
Implementation Method 5
Sorbinet filters of this type are also referred to as molecular sieves or molecular sieves for short and retain the elemental iodine in the relief flow comparatively well by sorption
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a method and corresponding device for depressurizing a nuclear power plant (2) having a containment shell (4) for containing activity carriers and having an outlet (10, 10') for a depressurization flow, wherein the depressurization flow is conducted out of the containment shell (4) into the atmosphere via a depressurization line (12, 12') provided with a filter system, wherein the filter system comprises a filter chamber (16) having a filter chamber inlet (124), a filter chamber outlet (128), and a sorbent filter (18) lying therebetween, and wherein the depressurization flow is first conducted in a high-pressure section (70), then is depressurized by means of expansion at a throttle device (72), then conducted at least partially through the filter chamber (16) having the sorbent filter (18), and finally blown out into the atmosphere. In order to enable an especially efficient and effective retention of activity carriers contained in the depressurization flow, in particular organic compounds containing iodine, the depressurization flow depressurized by the throttle device (72) is conducted through a superheating section (80) immediately before the depressurization flow enters the filter chamber (16), in which superheating section the depressurization flow is heated by direct or indirect heat transfer from the depressurization flow not yet depressurized in the high-pressure section (70) to a temperature that is at least 10 °C, preferably 20 °C to 50 °C, above the dew point temperature present there.