Filtered containment venting

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. 

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

C-12. L. Lindau and K. Ellisson, Filtered Containment Venting in Sweden , Proceedings of the Twentieth DOE/NRC Nuclear Air Cleaning Conference, NUREG/CP-0098, pp.695-707, U.S. 

Plant Name Type Designer Operational date Thermal power (MWt) Containment Type > Free volume (m=) Sprays " Containment Sump chemical Additives Filters" Containment Venting filters... 

The primary release of gaseous activities in a PWR is at the de-aerator after the heat exchanger in the primary loop. The hydrogen-oxygen recombiner is also located here. The gases are compressed and stored for up to 2 weeks before they (via filters) are vented through the stack these volumes are much smaller than for a BWR, whose off-gas also contains air leaked into the turbine on the condenser side. 

Containment, venting and suppression are not usually applicable to the reactor itself, but are used to protect downstream equipment such as blenders, dryers, and filter cabinets. They are not dealt with in this guide, but information is available in References 112, 117 and 118. Reference 11 illustrates a basis of safe operation relating to a particular type of reaction (phenolic resin production). Avoidance of sources of ignition and flammable conditions is described in Reference 110 and an outline is given below. 

Summary. In environmental protection, remediation of organic pollutants from the ground plays an important role. One possible way to achieve this goal is biode-gradation, i.e. decomposition by suitable species of bacteria. In principle we can think of two different situations, in the first case a suspension of bacteria infiltrates the contaminated soil, in the second one contaminated air (e.g. from soil venting) streams through a porous filter containing the bacteria. 

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... 

The purpose of this question was to find out whether any additional iodine mitigation measures have been planned or already implemented other than using additives in the spray and containment sump water and using controlled containment venting with a filter. Other than these measures, if already implemented, there are no other mitigation measures reported by the participating organizations. 

Plant name Filters (PF=prefilter, AF=absolute filter, ACF=active carbon filter, D = demister) Containment venting filters Passive iodine removal Iodine mitigation measures implemented/ planned Measurement of airborne iodine (gaseous and particulate form) activity ... 

No containment venting filters, no passive iodine removal, no controlled iodine release into environment, no other AM measures to mitigate airborne iodine activity in containment... 

Plant Name Containment Venting Filters Passive Iodine Removal Iodine Mitigation measures Measurement of airborne iodine in containment Measurement of controlled iodine (gaseous release into environment Other AM measures to mitigate (1) airborne iodine in containment... 

Kashiwazaki Kariwa -3 - Spray - SGTS (2) Filter - Suppression pool scrubbing in case of containment venting PASS (3) Yes ... 

Dillmann, H. G., Pasler, H., Wilhelm, J. G. Containment venting filter designs incorporating stainless-steel fiber filter. Kemtechnik 53, 75-80 (1988)... 

The product stream contains gases and soflds. The soflds are removed by using either cyclones, filters, or both in combination. Cyclones are devices used to separate soflds from fluids using vortex flow. The product gas stream must be cooled before being sent to the collection and refining system. The ALMA process uses cyclones as a primary separation technique with filters employed as a final separation step after the off-gas has been cooled and before it is sent to the collection and refining system (148). As in the fixed-bed process, the reactor off-gas must be incinerated to destroy unreacted butane and by-products before being vented to the atmosphere. 

The second line is the controlled release of materials through venting to containment/ confinement or through filters, scrubbers, flares, or overflow tanks. 

Answer Use the plant s PSA to determine the risk of accidents that include containment failure from overpressurization. Then make a preliminary design of a vented containment that has sufficiently low impedance to the gas at the pressure predicted for the most severe accident sequences such that the containment is not damaged. This containment bypass will include iodine and HEPA filters as well as scrubbers and a discharge through a stack. Estimate the dose that the population would get using this bypass for comparison with the PSA result for ruptured containment sequences. 

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