Filtered venting systems

For open filters, or when opening closed filters, solvent is flammable and may be above flash point with air present. For open filters, vent system failure may increase solvent vapor concentration, resulting in a fire or explosion. 

This period of time is also characterized by some new scientific views on some phenomena of interest, which were somewhat different from those prevailing (e.g. enhanced importance of the release of iodine as a compound with caesium, and the enhanced importance of aerosols) and by some characteristic technical choices (huge filtered venting systems, such as the Swedish FILTRA, see Figs 5-1 and 5-2, installed on the Barsebeck reactor). 

Containment support systems Condensation pool cooling and cleanup system, contammoit spray system, containment atmosphere control system, overpressure protection by filtered vent system... 

Proceedings of this conference provide a good indication of the state of engineering technology for the development of filtered venting systems. 

McArthur, D., Salaff, S. Canadas EFADS emergency filtered venting system. Nuclear Europe 1988, (10), 21-22... 

At the Lipari Landfill site in New Jersey, the gas venting system installed in 1983 consisted of two underground 4-inch (10-cm) perforated PVC pipes and five vent risers. Two parallel PVC pipes were installed 200 feet apart prior to cap emplacement during the period of wall construction and were placed about 3 feet beneath the finished grade. The vent risers were connected to the buried manifold pipes and consisted of open pipe installed perpendicular to the underground pipes and the ground surface. Filters were not attached to the riser exit points (U.S. EPA, 1987). 

They may also be required in industrial applications where they become part of venting systems on fermenters, centrifuges, autoclaves and freeze-dryers. Certain types of filter (membrane filters) also have an important role in sterility testing, where they can be employed to trap and concentrate contaminating organisms from solutions under... 

Internal tank pressure is also measured and transmitted to the control panel. If the relief valve is activated, the pressure is released to a line that vents directly to the stack. The normal tank venting system is connected to the process vessel off-gas system in the main plant, which is a filtered system. 

On the other hand, some proteins seem to show a gel concentration invariant with temperature (see Figure 3.58). In this case, the higher temperatures tend to denature the proteins (reducing their solubility), thereby compensating for the expected increase in solubility with temperature. Thus, the effect of temperature on gel concentration is complicated and often unique for the solute/sol-vent system being filtered. 

Containment enhancement provisions may also be part of a graded approach as augmentation or in I ieu of 10 CFR 50 containment design criteria. For an example, a filtered vented containment or confinement system may adequate protection to the public and onsite a containment heat removal system may not be reduce ultimate risk to an acceptable level, containment design criteria are used, the ultimate goal of protecting the health and safety of the public and onsite workers should be assured. 

Filtered containment venting system that would be operated in the longer term to prevent failure of the containment due to overpressurization following a severe accident. 

Fission product contauiment See tightness comrol above Tighuiess IS prnnaiily ensured by filtered vem system, leakages are collected by secondary containment venting Containment spray of drywell he wash out fission products from atmo here... 

Containment tightness control Indirectly, by vent system ( filters), see item 79... 

Filtered vented containment (Y/N) Y in long term only a Implemented system Filtered Air Discharge... 

Tightness control The surrounding reactor building serves as a secondary containment, kept at a below h atmospheric pressure, ventilation exhaust air passes through filters If over pressure protection of containment is found necessary, a small vent system can be ad 1... 

Filtered vented containmoit (Y/N). N Pressure suppression system (Y/N) Y... 

C-9. Proceedings of a Specialists Meeting on Filtered Containment Venting Systems,... 

The paper describes the multi-Venturi scrubber system developed in Sweden for filtered venting of reactor containments. Additional details can be found in E. Soderman, editor. Severe Accident Analysis in Sweden - Methods and Results, RAMA III Final Report, RAMA-III 89-02, ISBN 91-7010-116-7, December 1989. 

In partially leak-tight rooms sodium fires are extinguished by actuation of a filtered firefighting rarefaction vent system which reduces the oxygen concentration. To promote extinguishing nitrogen can be supplied to the room from special gas receivers. 

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