1、ANSI/ANS-55.6-1993 liquid radioactive waste processing system for light water reactor plants This standard has been reviewed and reaffirmed by the ANS Nuclear Facilities Standards Committee (NFSC) with the recognition that it may reference other standards and documents that may have been superceded
2、or withdrawn. The requirements of this document will be met by using the version of the standards and documents referenced herein. It is the responsibility of the user to review each of the references and to determine whether the use of the original references or more recent versions is appropriate
3、for the facility. Variations from the standards and documents referenced in this standard should be evaluated and documented. This standard does not necessarily reflect recent industry initiatives for risk informed decision-making or a graded approach to quality assurance. Users should consider the
4、use of these industry initiatives in the application of this standard. Secretariat American Nuclear Society Prepared by the American Nuclear Society Standards Committee Working Group ANS-55.6 Published by the American Nuclear Society 555 North Kensington Avenue ANSI/ ANS-55.6-1993 American National
5、Standard for Liquid Radioactive Waste Processing System for Light Water Reactor Plants La Grange Park, lllinois 60525 USA Approved July 16, 1993 by the American National Standards Institute, Inc. American National Standard Designation of this document as an American National Standard attests that th
6、e principles of openness and due process have been followed in the approval procedure and that a consensus of those directly and materially affected by the standard has been achieved. This standard was developed under the procedures of the Standards Committee of the American Nuclear Society; these p
7、rocedures are accredited by the American National Standards Institute, Inc., as meeting the criteria for American National Standards. The consensus committee that approved the standard was balanced to ensure that competent, concerned, and varied interests have had an opportunity to participate. An A
8、merican National Standard is intended to aid industry, consumers, govern mental agencies, and general interest groups. Its use is entirely voluntary. The existence of an American National Standard, in and of itself, does not preclude anyone from manufacturing, marketing, purchasing, or using product
9、s, processes, or procedures not conforming to the standard. By publication of this standard, the American Nuclear Society does not insure anyone utilizing the standard against liability allegedly arising from or after its use. The content of this standard reflects acceptable practice at the time of
10、its approval and publication. Changes, if any, occurring through developments in the state of the art, may be considered at the time that the standard is subjected to periodic review. It may be reaffirmed, revised, or withdrawn at any time in accordance with established procedures. Users of this sta
11、ndard are cautioned to determine the validity of copies in their possession and to establish that they are of the latest issue. The American Nuclear Society accepts no responsibility for interpretations of this standard made by any individual or by any ad hoc group of individuals. Requests for inter
12、pretation should be sent to the Standards Department at Society Headquarters. Action will be taken to provide appropriate response in accordance with established procedures that ensure consensus on the interpretation. Comments on this standard are encouraged and should be sent to Society Headquarter
13、s. Published by American Nuclear Society 555 North Kensington Avenue, La Grange Park, Dlinois 60525 USA Copyright 1994 by American Nuclear Society. Any part of this standard may be quoted. Credit lines should read Extracted from American National Standard ANSLANS-55.6-1993 with permission of the pub
14、lisher, the American Nuclear Society.“ Reproduction prohibited under copyright convention unless written permission is granted by the American Nuclear Society. Printed in the United States of America Foreword (This foreword is not a part of American National Standard for Liquid Radioactive Waste Pro
15、cessing System for Light Water Reactor Plants, ANSJ/ANS-55.6-1993, but is included for information purposes only.) Management of the liquid radioactive waste generated as a by-product of nuclear power plant operation constitutes a major responsibility of management. Quantities of liquid radioactive
16、waste generated during operation are dependent upon several factors, including design conditions, type of equipment, equipment arrangement, and operating philosophy. The purpose of this standard is to establish uniform practices and set forth minimum requirements for design, construction, and perfor
17、mance, with due consideration for operation, for acceptable liquid radioactive waste handling and processing systems. Adherence by system designers to the criteria contained in the standard will enable the operator: (a) to control to within regulatory levels radiation exposures to operating personne
18、l; (b) to assure a low probability of accidental release of radioactivity from the system; and (c) to control system releases of radioactivity to levels as low as reasonably achievable. In accordance with ANS policy to maintain standards on a five-year basis, the standard was revised to update its c
19、ontents and to reflect changes in industry practices. Members of Working Group 55.6, and their affiliations at the time of their approval of this standard, were as follows: F. W. Hartley, Chairman, Management Analysis Company J. A. Battaglia, Westinghouse Electric Corporation D. H. DaCosta, Ergenics
20、, Inc. S. A. Lamanna, The Babcock the word “should“ to denote a recommendation; and the word “may“ to denote permission, neither a requirement nor a recommendation. slurry wastes. Liquid radioactive wastes of high insoluble solids content (greater than 0.1% solids by weight). system and equipment wa
21、stes. Liquid from radioactive components, equipment, or systems, and from component cooling systems. 2 3. Criteria 3.1 Performance Criteria 3.1.1 Releases. The LRWPS shall be designed so that radioactive materials in liquid effiuents from the plant meet the requirements of the following: (a) Title 1
22、0, “Energy,“ Code ofFederalRegu lations, Part 50, “Licensing of Production and Utilization Facilities,“ (10 CFR 50) Section 50.34a 4. (b) The limits specified in Title 10, “Energy,“ Code of Federal Regulations, Part 20, “Standards for Protection Against Radiation“ (10 CFR 20) 5. (c) Control and moni
23、toring of releases of radioactive materials to the environment shall meet the requirements of Title 10, “Energy,“ Code of Federal Regulations, Part 50, “Licensing of Production and Utilization Facilities,“ Appen dix A, “General Design Criteria for Nuclear Power Plants,“ Criteria 60 and 64 6. (d) The
24、 numerical guide for design objectives and limiting conditions for operation to meet the criterion “as low as reasonably achievable“ (ALARA) for radioactive material in light water cooled nuclear power plant effiuent, Title 10, “Energy,“ Code of Federal Regulations, Part 50, “Licensing of Production
25、 and Utilization Facili ties,“ Appendix I, “Numerical Guides for Design Objectivesand Limiting Conditions for Operation to Meet the Criterion As Low as is Reasonably Achievable for Radioactive Material in Light Water-Cooled Nuclear Power Reactor Effluents“ 7. (e) Federal, state, and local environmen
26、tal requirements. 3.2 Safety Criteria. The LRWPS shall be de signed so that concentration of radioactive mate rial released to the environment or exposure to the general public do not exceed the require ments of 10 CFR 20 5. 3.3 Operational Criteria. The design, con struction, and operation of the L
27、RWPS shall be such that radiation exposures to operating and maintenance personnel are maintained ALARA in accordance with 10 CFR 20 5. 4. Design Requirements 4.1 Code Classification. Equipment and piping shall be designed, constructed, and tested in accordance with the requirements of the applica b
28、le codes as given in Table 1. 4.2 Seismic Design. The LRWPS equipment is not required to be designed to withstand the effects of a seismic event. The building(s) housing the principal LRWPS equipment shall be designed to contain2 the liquid inventory of the building in the event of an operating basi
29、s earthquake (OBE). The build ing(s) need not be designed in accordance with Seismic Category I requirements. 3 Dikes and retention basins for outdoor liquid radwaste tanks shall be capable of preventing runoff in the event of a tank overflow and should have provisions for sampling collected liquids
30、 and routing them to the LRWPS. The dikes and retention basins need not be designed in accor dance with Seismic Category I requirements. 4.3 Quality Assurance. The design, procure ment, fabrication, and construction activities shall conform to the quality assurance provisions of the codes and standa
31、rds specified in Table 1. In addition, the following quality control features shall be established as a minimum. 4.3.1 System Designer and Procurer 4.3.1.1 Design and Procurement Docu ment Control. Design and procurement docu ments shall be verified for conformance to the requirements of this standa
32、rd by an individual or individuals within the design organization who are not the originators of the document. Changes to these documents shall be verified or controlled to maintain conformance to this standard. 4.3.1.2 Control of Purchased Material, Equipment, and Services. Measures shall be establ
33、ished to ensure that suppliers of material, 2 The term “contain“ means that the building shall have sufficient volume so that the liquid would not overflow, and does not imply absolute containment for an indefinite period of time. 3 Guidance for seismic design requirements can be found in the U.S. N
34、uclear Regulatory Commissions Regulatory Guide 1.143, Design Guidance for Radioactive Waste Management Systems, Structures, and Components Installed in Light Water-Cooled Nuclear Power Plants,“ U.S. Nuclear Regulato ry Commission, Washington, D.C. American National Standard ANSI/ANS-55.6-1993 equipm
35、ent, and construction services are capable of supplying these items to the quality specified in the procurement documents. This may be done by an evaluation or a survey of the suppliers products and facilities. 4.3.1.3 Handling, Storage, and Shipping. Instructions shall be provided in procurement do
36、cuments to control the handling, storage, ship ping, and preservation of material and equipment to prevent damage, deterioration, and reduction of cleanliness. 4.3.2 System Constructor 4.3.2.1 Inspection. In addition to required code inspections, a program for inspection of activi ties affecting qua
37、lity shall be established and executed by, or for, the organization perlorming the activity to verify conformance with the documented instructions, procedures, and drawings for accom plishing the activity. This shall include the visual inspection of components prior to installation for conformance w
38、ith procurement documents and the visual inspection of items and systems following installation, cleaning, and passivation (where applied). 4.3.2.2 Inspection, Test, and Operating Status. Measures shall be established to provide for the identification of items which have satis factorily passed requi
39、red inspections and tests. 4.3.2.3 Identification and Corrective Ac tion for Items of Nonconformance. Measures shall be established to identify items of nonconfor mance with regard to the requirements of the 1-:ocurement documents or applicable codes and standards and to identify the action taken to
40、 correct such items. 4.4 Materials. Materials for pressure retaining components of process systems shall be selected from those covered by the material specifications listed in Table 1, except that malleable, wrought, or cast iron materials shall not be used. The compo nents shall meet all of the ma
41、ndatory requirements and the material specifications with regard to manufacture, examination, repair, testing, identifi cation, and certification. 4.5 Welding. All welding constituting the pressure boundary of pressure retaining components and piping shall be perlormed in accordance with the require
42、ments of Table 1. Pressure retaining components of the LRWPS shall 3 American National Standard ANSYANS-55.6-1993 utilize welded construction to the maximum practi cal extent. Nonconsumable backing rings shall not be used in lines carrying high concentrations of solids, resins, or other particulate
43、material Butt weld joints or butt welds with consumable inserts shall be used on all process piping with the following exceptions: (a) Flanged joints or suitable rapid disconnect fittings shall be used only where maintenance or operational requirements clearly indicate such construction to be prefer
44、able. (b) For lines, other than slurry lines, that have nominal sizes between %,-in. and 2lh-in., socket welded or mechanical joints may be used. (c) Screwed connections in which threads pro vide the only seal shall not be used, except for instrumentation connections or pump casing vents and drains,
45、 where welded connections are not suitable. 4.6 Sampling. Provisions shall be made to allow adequate recycle and mixing to ensure that repre sentative samples can be obtained from waste monitoring and hold-up tanks. The purposes for sampling and the analytical determinations to be made on each sampl
46、e might differ from station to station. However, sample points shall be provided in accordance with Table 2 as a minimum. Sample lines for all frequently taken samples should be routed to a common sample station. This station should be located in an area that is easily accessible to the operator, an
47、d so that operator exposure can be maintained ALARA (unless the sample station is so remote from the sample point that representative samples could not be obtained). Connections of sample lines to process piping shall be via a probe or other method capable of obtaining a representative sample of the
48、 stream being sam pled. Connections shall be made at the side or the top of horizontal piping. Sample lines shall be routed so as to be as short and direct as possible. Sample lines shall be Ameri can Iron and Steel Institute (AISU Type 304 or 316 stainless steel (or appropriate coiTOsion resistant
49、material) tubing that has been sized to maintain turbulent flow. The Reynolds number (Re) at the minimum sample flow shall be at least 4,000. Sample tubing shall be 0.049 inches minimum wall 4 thickness for flareness and 0.065 inches minimum wall thickness for tubing with welded fittings. Welded fittings are prefened; refer to American National Standard for Sample Line Piping and Tubing for Use in Nuclear Power Plants, ANSIIISA 567.10-1986 8. Wherever slurries are sampled, the nnmmum tubing diameter shall be 3/8-in. outside diameter, and all bends shall have a minim
