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Nuclear Regulatory Commission Pt. 110, App. K

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Nuclear Regulatory Commission Pt. 110, App. K Nuclear Regulatory Commission Pt. 110, App. K calcium fluoride slag. The main functions in- liquid ammonia flows from the top to the volved in this process are the following: bottom. The deuterium is stripped from the fluorination (e.g., involving equipment fab- hydrogen in the synthesis gas and con- ricated or lined with a precious metal), centrated in the ammonia. The ammonia metal reduction (e.g., employing ceramic then flows into an ammonia cracker at the crucibles), slag recovery, product handling, bottom of the tower while the gas flows into ventilation, waste management and process an ammonia converter at the top. Further control. The process systems are particu- enrichment takes place in subsequent stages larly adapted so as to avoid criticality and and reactor-grade heavy water is produced radiation effects and to minimize toxicity through final distillation. The synthesis gas hazards. Other processes include the feed can be provided by an ammonia plant fluorination of plutonium oxalate or pluto- that can be constructed in association with a nium peroxide followed by reduction to heavy water ammonia-hydrogen exchange metal. plant. The ammonia-hydrogen exchange (c) Any other components especially de- process can also use ordinary water as a feed signed or prepared for use in a uranium con- source of deuterium. version plant or plutonium conversion plant C.1. Much of the key equipment for heavy or in any of the components described in this water production plants using either the GS appendix. process or the ammonia-hydrogen exchange process are common to several segments of [61 FR 35606, July 8, 1996, as amended at 65 the chemical and petroleum industries; par- FR 70291, Nov. 22, 2000; 79 FR 39298, July 10, ticularly in small plants using the GS proc- 2014] ess. However, few items are available ‘‘off- the-shelf.’’ Both processes require the han- APPENDIX K TO PART 110—ILLUSTRATIVE dling of large quantities of flammable, corro- LIST OF EQUIPMENT AND COMPO- sive, and toxic fluids at elevated pressures. NENTS UNDER NRC EXPORT LICENS- Therefore, in establishing the design and op- ING AUTHORITY FOR USE IN A PLANT erating standards for plants and equipment using these processes, careful attention to FOR THE PRODUCTION OF HEAVY materials selection and specifications is re- WATER, DEUTERIUM AND DEUTERIUM quired to ensure long service life with high COMPOUNDS safety and reliability factors. The choice is primarily a function of economics and need. NOTE: Heavy water can be produced by a Most equipment, therefore, is prepared to variety of processes. However, two processes customer requirements. have proven to be commercially viable: The In both processes, equipment which indi- water-hydrogen sulphide exchange process vidually is not especially designed or pre- (GS process) and the ammonia-hydrogen ex- pared for heavy water production can be as- change process. sembled into especially designed or prepared A. The GS process is based upon the ex- systems for producing heavy water. Exam- change of hydrogen and deuterium between ples of such systems are the catalyst produc- water and hydrogen sulphide within a series tion system used in the ammonia-hydrogen of towers which are operated with the top exchange process and the water distillation section cold and the bottom section hot. systems used for the final concentration of Water flows down the towers while the hy- heavy water to reactor-grade in either proc- drogen sulphide gas circulates from the bot- ess. tom to the top of the towers. A series of per- C.2. Equipment especially designed or pre- forated trays are used to promote mixing be- pared for the production of heavy water uti- tween the gas and the water. Deuterium mi- lizing either the water-hydrogen sulphide ex- grates to the water at low temperatures and change process or the ammonia-hydrogen ex- to the hydrogen sulphide at high tempera- change process: tures. Gas or water, enriched in deuterium, (i) Water-hydrogen Sulphide Exchange is removed from the first stage towers at the Towers. junction of the hot and cold sections and the Exchange towers with diameters of 1.5 m process is repeated in subsequent stage tow- or greater and capable of operating at pres- ers. The product of the last stage, water en- sures greater than or equal to 2 MPa (300 psi) riched up to 30 percent in deuterium, is sent especially designed or prepared for heavy to a distillation unit to produce reactor water production utilizing the water-hydro- grade heavy water; i.e., 99.75 percent deute- gen sulphide exchange process. rium oxide. (ii) Blowers and Compressors. B. The ammonia-hydrogen exchange proc- Single stage, low head (i.e., 0.2 MPa or 30 ess can extract deuterium from synthesis gas psi) centrifugal blowers or compressors for through contact with liquid ammonia in the hydrogen-sulphide gas circulation (i.e., gas presence of a catalyst. The synthesis gas is containing more than 70 percent H2S). The fed into exchange towers and then to an am- blowers or compressors have a throughput monia converter. Inside the towers the gas capacity greater than or equal to 56 m3/sec- flows from the bottom to the top while the ond (120,000 standard cubic feet per minute) 745 VerDate Sep<11>2014 14:17 Mar 11, 2016 Jkt 238031 PO 00000 Frm 00755 Fmt 8010 Sfmt 8002 Y:\SGML\238031.XXX 238031 jstallworth on DSK7TPTVN1PROD with CFR Pt. 110, App. L 10 CFR Ch. I (1–1–16 Edition) while operating at pressures greater than or production of heavy water, deuterium, and equal to 1.8 MPa (260 psi) suction and have deuterium compounds or in any of the com- seals designed for wet H2S service. ponents described in this appendix. (iii) Ammonia-Hydrogen Exchange Towers. Ammonia-hydrogen exchange towers great- [79 FR 39298, July 10, 2014] er than or equal to 35 m (114.3 ft) in height with diameters of 1.5 m (4.9 ft) to 2.5 m (8.2 APPENDIX L TO PART 110—ILLUSTRATIVE ft) capable of operating at pressures greater LIST OF BYPRODUCT MATERIALS than 15 MPa (2225 psi). The towers have at UNDER NRC EXPORT/IMPORT LICENS- least one flanged, axial opening of the same ING AUTHORITY A diameter as the cylindrical part through which the tower internals can be inserted or Actinium 225 (Ac 225) Cesium 131 (Cs 131) withdrawn. Actinium 227 (Ac 227) Cesium 134m (Cs (iv) Tower Internals and Stage Pumps Used Actinium 228 (Ac 228) 134m) in the Ammonia-hydrogen Exchange Process. Americium 241 (Am Cesium 134 (Cs 134) Tower internals include especially de- 241) Cesium 135 (Cs 135) signed stage contactors which promote inti- Americium 242m (Am Cesium 136 (Cs 136) mate gas/liquid contact. Stage pumps in- 242m) Cesium 137 (Cs 137) clude especially designed submersible pumps Americium 242 (Am Chlorine 36 (Cl 36) for circulation of liquid ammonia within a 242) Chlorine 38 (Cl 38) contacting stage internal to the stage tow- Americium 243 (Am Chromium 51 (Cr 51) ers. 243) Cobalt 57 (Co 57) (v) Ammonia Crackers Utilizing the Am- Antimony 124 (Sb 124) Cobalt 58m (Co 58m) monia-hydrogen Exchange Process. Antimony 125 (Sb 125) Cobalt 58 (Co 58) Ammonia crackers with operating pres- Antimony 126 (Sb 126) Cobalt 60 (Co 60) sures greater than or equal to 3 MPa (450 psi) Arsenic 73 (As 73) Copper 64 (Cu 64) especially designed or prepared for heavy Arsenic 74 (As 74) Curium 240 (Cm 240) water production utilizing the ammonia-hy- Arsenic 76 (As 76) Curium 241 (Cm 241) drogen exchange process. Arsenic 77 (As 77) Curium 242 (Cm 242) (vi) Ammonia Synthesis Converters or Barium 131 (Ba 131) Curium 243 (Cm 243) Synthesis Units. Barium 133 (Ba 133) Curium 244 (Cm 244) Ammonia synthesis converters or syn- Barium 140 (Ba 140) Curium 245 (Cm 245) thesis units especially designed or prepared Bismuth 207 (Bi 207) Curium 247 (Cm 247) for heavy water production utilizing the am- Bismuth 210 (Bi 210) Dysprosium 165 (Dy monia-hydrogen exchange process. Bromine 82 (Br 82) 165) These converters or units take synthesis Cadmium 109 (Cd 109) Dysprosium 166 (Dy gas (nitrogen and hydrogen) from an ammo- Cadmium 113 (Cd 113) 166) nia/hydrogen high-pressure exchange column Cadmium 115m (Cd Einsteinium 252 (Es (or columns), and the synthesized ammonia 115m) 252) is returned to the exchange column (or col- Cadmium 115 (Cd 115) Einsteinium 253 (Es umns). Calcium 45 (Ca 45) 253) (vii) Infrared Absorption Analyzers. Calcium 47 (Ca 47) Einsteinium 254 (Es Infrared absorption analyzers capable of Californium 248 (Cf 254) ‘‘on-line’’ hydrogen/deuterium ratio analysis 248) Einsteinium 255 (Es where deuterium concentrations are equal to Californium 249 (Cf 255) or greater than 90 percent. 249) Erbium 169 (Er 169) (viii) Catalytic Burners Used in the Ammo- Californium 250 (Cf Erbium 171 (Er 171) nia-hydrogen Exchange Process. 250) Europium 152 (Eu 152) Catalytic burners for the conversion of en- Californium 251 (Cf Europium 152 9.2 h riched deuterium gas into heavy water espe- 251) (Eu 152 9.2 h) cially designed or prepared for heavy water Californium 252 (Cf Europium 152 13 yr production utilizing the ammonia-hydrogen 252) (Eu 152 13 yr) exchange process. (ix) Complete Heavy Water Upgrade Sys- Californium 253 (Cf Europium 154 (Eu 154) tems or Columns. 253) Europium 155 (Eu 155) Complete heavy water upgrade systems or Californium 254 (Cf Fermium 257 (Fm 257) columns especially designed or prepared for 254) Fluorine 18 (F 18) the upgrade of heavy water to reactor-grade Carbon 11 (C 11) Gadolinium 148 (Gd deuterium concentration. These systems, Carbon 14 (C 14) 148) which usually employ water distillation to Cerium 141 (Ce 141) Gadolinium 153 (Gd separate heavy water from light water, are Cerium 143 (Ce 143) 153) especially designed or prepared to produce Cerium 144 (Ce 144) Gadolinium 159 (Gd reactor-grade heavy water (i.e., typically Cesium 129 (Cs 129) 159) 99.75 percent deuterium oxide) from heavy water feedstock of lesser concentration.
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