1、NUCLEAR POWER PLANT AIR-CLEANINGUNITS ANDCOMPONENTSAN ASME STANDARDASME N5092002Revision of ASME N5091989 (R1997)Intentionally left blank AN AMERICAN NATIONAL STANDARDNUCLEARPOWER PLANTAIR-CLEANINGUNITS ANDCOMPONENTSANSI / ASME N509-2002Revision of ASME N509-2002 (R1997)Date of Issuance: March 26, 2
2、003This Standard will be revised when the Society approves the issuance of a new edition. There willbe no addenda issued to this edition.ASME issues written replies to inquiries concerning interpretations of technical aspects of thisStandard. Interpretations are published on the ASME Web site under
3、the Committee Pages at http:/www.asme.org/codes/ as they are issued.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or standard was developed under procedures accredited as meeting the criteria for American NationalStandards. The Standards Committee that ap
4、proved the code or standard was balanced to assure that individuals fromcompetent and concerned interests have had an opportunity to participate. The proposed code or standard was madeavailable for public review and comment that provides an opportunity for additional public input from industry, acad
5、emia,regulatory agencies, and the public-at-large.ASME does not “approve,” “rate,” or “endorse” any item, construction, proprietary device, or activity.ASME does not take any position with respect to the validity of any patent rights asserted in connection with anyitems mentioned in this document, a
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7、f such rights, isentirely their own responsibility.Participation by federal agency representative(s) or person(s) affiliated with industry is not to be interpreted asgovernment or industry endorsement of this code or standard.ASME accepts responsibility for only those interpretations of this documen
8、t issued in accordance with the establishedASME procedures and policies, which precludes the issuance of interpretations by individuals.No part of this document may be reproduced in any form,in an electronic retrieval system or otherwise,without the prior written permission of the publisher.The Amer
9、ican Society of Mechanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2003 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.CONTENTSForeword ivCommittee Roster v1 Scope 11.1 Limitations. 11.2 Purpose 12 Applicable Documents . 13 Terms and Definition
10、s . 14 Functional Design . 14.1 General 14.2 Design Parameters 24.3 Size (Installed Capacity) of Air-Cleaning Unit . 24.4 Environmental Design Condition 24.5 Structural Load Requirements. 24.6 Air-Cleaning Units and Components That Must Withstand Fan PeakPressure . 24.7 Nuclear Air-Treatment System
11、Configuration and Location 34.8 Maintainability Criteria . 34.9 Monitoring of Operational Variables 44.10 Adsorbent Cooling . 44.11 Fire Protection 44.12 Insulation 44.13 Testability 44.14 Pressure Boundary Leakage. 55 Components 55.1 HEPA Filters . 55.2 Tray-Type Bed and Deep Bed Adsorber Cells 55.
12、3 Prefilters and Postfilters 55.4 Moisture Separators 55.5 Air Heaters 55.6 Filter Housing 65.7 Fans . 65.8 Fan Drives . 65.9 Dampers . 65.10 Ducts 66 Packaging, Shipping, Receiving, Storage, and Handling of Components 67 Installation and Erection 67.1 Drawings 67.2 Erection 77.3 Welding 77.4 Instal
13、lation of HEPA Filters and Adsorbers 78 Quality Assurance . 79 Acceptance Testing 7Mandatory AppendixI Sampling of Installed Adsorbents for Surveillance Testing 9iiiFOREWORDThis Standard covers requirements for the design, construction, and testing of units andcomponents which make up high efficienc
14、y air and gas cleaning systems used in nuclear powerplants. The standard was originally developed by the American National Standards CommitteeN45 on Reactor Plants.This Standard specifies acceptance testing, including minimum acceptance requirements, inaccordance with the standard prepared by the co
15、mpanion ad hoc working group, “Testing ofNuclear Air Cleaning Systems.” It was originally approved on December 7, 1976 by the AmericanNational Standards Institute and designated N509-1976.In 1975, the N45.8 Subcommittee was reorganized into the ASME Committee on Nuclear Airand Gas Treatment and bega
16、n operating under the accredited ASME Procedures for NuclearProjects which received accreditation on January 15, 1976. The ASME Committee on Nuclear Airand Gas Treatment was chartered to develop, review, maintain, and coordinate Codes and Stan-dards for design, fabrication, installation, testing, an
17、d inspection of equipment for gas treatmentfor nuclear power plants.Suggestions for improvement gained in the use of this Standard will be welcomed. They shouldbe sent to the Secretary, Committee on Nuclear Air and Gas Treatment, The American Societyof Mechanical Engineers, Three Park Avenue, New Yo
18、rk, NY 10016.This Standard was approved by the ASME Committee on Nuclear Air and Gas Treatment andapproved as an American National Standard by the American National Standards Institute onNovember 6, 2002.ivASME COMMITTEE ON NUCLEAR AIR AND GAS TREATMENT(The following is the roster of the Committee a
19、t the time of approval of this Standard.)MAIN COMMITTEER. D. Porco, ChairJ. D. Paul, Vice ChairC. A. Sanna, SecretaryCOMMITTEE PERSONNELL. T. Ahlman, RaytheonR. R. Bellamy, U.S. Nuclear Regulatory CommissionJ. R. Edwards, CSC/FlandersM. W. First, Harvard School of Public HealthM. J. Fox, Engineered
20、Environments, Inc.C. Golden, ConsultantC. E. Graves, NUCON International, Inc.M. R. Hargan, Hargan EngineeringJ. J. Hayes, Jr., U.S. Nuclear Regulatory CommissionCONAGT HONORARYD. J. Gladden, ConsultantL. J. Klaes, ConsultantW. H. Miller, Sargent Order Department: 22 Law Drive,Box 2300, Fairfield, N
21、J 07007-23003 TERMS AND DEFINITIONSTerms and Definitions are located in ASME AG-1,Article AA-1000 and various specific ASME AG-1 Codesections.4 FUNCTIONAL DESIGN4.1 GeneralDepending on the function of the system and theconditions under which it will operate, air-cleaning unitsinclude some or all of
22、the following internal components.(a) Prefilters are required in air-cleaning units whendesign inlet particulate concentrations and particle sizeare such that the HEPA filter may be rendered ineffectiveprematurely. On other air-cleaning units prefilters arerecommended only when it is desired to incr
23、ease HEPAfilter life.(b) HEPA filters are required in all air-cleaning unitswhen filtration of inlet particulate matter requires a min-imum efficiency of 99.97% for particles equal to 0.3micrometer in size.(c) Adsorbers are required when air-cleaning unitsare designed for removal of adsorbable compo
24、unds.(d) Moisture separators (demisters) are requiredwhen entrained water droplet concentration may begreater than 1 lb (0.45 kg) of water per 1,000 cfm (1,700m3/hr) of airflow.(e) Heaters should be utilized for air-cleaning unitswith adsorbers when the relative humidity of air to theadsorber exceed
25、s 70% based upon the 1% percentilemeteorological conditions (where applicable). Fornuclear air-treatment systems which are unaffected byoutside air meteorological conditions, heaters should beutilized when an accident would result in an airstreamexceeding 70% relative humidity for more than 1 hr.(f)
26、 Postfilters. When adsorbers are used in ESF air-cleaning units, provision shall be made for a postfilter1ASME AG-1 contains Code requirements for nuclear air andgas treatment equipment. See Article AA-2000.ASME N509-2002 NUCLEAR POWER PLANT AIR-CLEANING UNITS AND COMPONENTSto retain carbon fines. P
27、ostfilters should also be consid-ered in non-ESF air-cleaning units discharging into occu-pied spaces where carbon fine carryover is notacceptable.4.2 Design ParametersValues of the following design parameters shall bespecified when invoking this Standard and shall be usedwherever referenced:(a) vol
28、umetric air flow rate, acfm (m3/hr);(1) minimum flow rate;(2) maximum flow rate;(3) design flow rate;(b) design pressures, in. w.g. (Pa);(1) maximum operating pressure;(2) leak test pressure;(3) maximum design pressure;(4) structural capability pressure (usually deter-mined by component designer);(c
29、) pressure-time transient (if applicable), in. w.g./sec(Pa/sec);(d) maximum and minimum gas temperature, F(C)and density, lb/ ft3(kg/m3);(e) maximum inlet relative humidity, %;(f) entrained liquid water, (mass flow rate), lb/min(kg/min);(g) concentrations of specific contaminants in air-stream;(h) r
30、equired decontamination factors for each con-taminant;(i) component radiation integrated life dose (rad) andmaximum dose rate (rad/hr);(j) maximum dirty filter pressure differential, in.w.g. (Pa);(k) structural loadings;(l) duct and housing maximum permissible leak rate,scfin (m3/hr) and associated
31、operating pressure, in.w.g. (Pa);(m) environmental design conditions including tem-perature, pressure, and relative humidity;(n) expected duration and environmental conditionsof storage area;(o) particle size distribution and quantity of aerosolsand contaminants under normal and accident conditions(
32、if known);(p) safety classification (ESF or non-ESF);(q) number of adsorber test cannisters per adsorberbank;(r) heater capacity, watts, voltage, temperature differ-ential, if applicable.4.3 Size (Installed Capacity) of Air-Cleaning UnitThe installed capacity cfm (m3/hr) of the air cleaningunit shal
33、l be no greater than the limiting installed capac-ity of any bank of components contained in the air-cleaning unit through which the airflow must pass. The2installed capacity of any bank or stage of componentsshould not exceed the number of components in thebank times the rated capacity of the indiv
34、idual compo-nents. Test cannisters shall not be included in determin-ing the installed capacity of any bank or stage ofadsorbers.4.4 Environmental Design ConditionAll parts and components of the air-cleaning unit shallbe selected or designed to operate under the environ-mental conditions (temperatur
35、e, relative humidity, pres-sure, radiation, etc.) specified in para. 4.2. Materials ofconstruction and components shall be selected or treatedto limit generation of combustibles and contaminantsand to resist corrosion and degradation that would resultin loss of function when exposed to the specified
36、 envi-ronmental conditions for the design life of the com-ponent.Environmental qualification requirements are con-tained in 10 CFR 50.49, IEEE 323 and ASME AG-1, Sec-tion AA and various specific ASME AG-1 Code sections.4.5 Structural Load RequirementsESF systems and all of their components shall bes
37、hown, either by testing or by a mathematical technique,to remain functional under the structural loading speci-fied in ASME AG-1, Article AA-4000 and various specificASME AG-I Code sections.4.6 Air-Cleaning Units and Components That MustWithstand Fan Peak PressureThe maximum design pressure shall be
38、 documentedby calculation, including the basis for the condition, andincluded in procurement specifications for manufactur-ers design.(a) Positive Pressure. Air-cleaning units and compo-nents including ducts located on the discharge side offan(s) which can be isolated by closure of a downstreamdampe
39、r, or potentially plugged components, shall bedesigned to withstand a positive internal pressure equalto or greater than the peak pressure of the fan(s). Ifprovision is made to deenergize fan(s) on high differen-tial pressure or low flow, the components shall bedesigned to withstand the trip point d
40、esign pressureplus a margin to include the rate of pressure rise betweenreaching the pressure setpoint and the time for theinstrumentation response, or 10%, whichever is greater.(b) Negative Pressure. Air-cleaning units and compo-nents located on the inlet side of fan(s) which can beisolated by clos
41、ure of an upstream damper, or poten-tially plugged components shall be designed to with-stand a negative internal pressure equal to or morenegative than the peak pressure of the fan(s). If provisionis made to deenergize fan(s) on high differential pressureor low flow, the components shall be designe
42、d to with-stand the trip point design pressure plus a margin toNUCLEAR POWER PLANT AIR-CLEANING UNITS AND COMPONENTS ASME N509-2002include the rate of pressure rise between reaching thepressure setpoint and the time for the instrumentationresponse, or 10%, whichever is greater.4.7 Nuclear Air-Treatm
43、ent System Configuration andLocationPhysical location and arrangement of the componentsof a nuclear air-treatment system influence the require-ments for leak tightness for the various parts of thepressure boundary. Air flow should be from potentiallyless contaminated areas to potentially more contam
44、i-nated areas. Whenever possible, routing of contami-nated air through clean spaces or interspaces should beavoided. If this can not be done, the general guidancein this Section should be followed.Figures B-1410-1, B-1410-2, and B-1410-3 of ASME AG-1, Section SA schematically depict examples of poss
45、iblecombinations and location of fan and air-cleaning unitto minimize impact of system contaminated outleakageon surrounding clean spaces and interspaces as well ascontaminated inleakage into a cleaner system com-ponent.4.7.1 Effluent Nuclear Air-Treatment System (Once-Through)(a) Maintain ducts con
46、veying contaminated airthrough clean spaces or clean interspaces at a negativepressure with respect to the surrounding areas.(b) With air-cleaning unit located in a cleaninterspace, locate exhaust fan downstream of air-clean-ing unit in order to keep air-cleaning unit under negativepressure. Any lea
47、kage through fan shaft will be fromclean interspace.(c) When air-cleaning units are located in contami-nated spaces or interspaces, the fan shall be locatedupstream of the air-cleaning unit in order to keep air-cleaning unit under positive pressure and to preventinfiltration of contaminated air thro
48、ugh fan shaft, orinto the filter housing downstream of filters, therebybypassing filters.(d) The length of positive pressure discharge ductsfrom the air-cleaning unit routed through clean spacesor interspaces should be kept as short as practical tominimize outleakage from ductwork from impacting in-
49、plant personnel exposure.4.7.2 Habitability Systems(a) Outside air ducts routed through clean spaces orinterspaces that may convey radioactive air following arelease shall be under a negative pressure relative to thespaces.(b) Negative pressure recirculating air ducts that passoutside the habitable space should be avoided or addi-tional filtration provided.(c) The makeup air fan shall be located:(1) upstream of air-cleaning unit if air-cleaning unitis in a contaminated space;3(2) downstream of air-cleaning unit if air-cleaningunit is in a clean space.(d) The length of positive pres
