104:. A basic requirement for the success of this method is that the axial-flow compressors successfully transmit parallel streams of different isotopic compositions without significant mixing. A typical Helikon module consists of a large cylindrical steel vessel housing the 20 separator assemblies, along with two compressors (one mounted on each end), and two water-cooled
91:
separation. The spiral swirling flow decays downstream of the feed inlet due to friction at the tube wall. Consequently, the inside diameter of the tube is typically tapered to reduce decay in the swirling flow velocity. This process is characterized by a separating element with a very small stage
87:. The tube tapers to a small exit aperture at one or both ends. This tangential injection of gas results in a spiral or vortex motion within the tube, and two gas streams are withdrawn at opposite ends of the vortex tube; centrifugal force providing the
99:
required to link stages together, the design was developed into a cascade design technique (dubbed
Helikon), in which 20 separation stages are combined into one module, and all 20 stages share a common pair of
63:. Aerodynamic enrichment processes require large amounts of electricity and are not generally considered economically competitive because of high energy consumption and substantial requirements for removal of
67:. There are other ways in which it is advantageous, e.g. In simplicity, lack of precision required, even if more expensive. The South African enrichment plant was closed on 1 February 1990.
115:
due to the highly diluted feedstock and suitability for batch processing. This means
Helikon-type plants can be relatively small, making the technology a
128:
48:
301:
256:
251:
180:
306:
39:
at
Cambridge. Other methods of separation were more practical at that time, but this method was designed and used in
291:
281:
286:
83:
is injected tangentially into a tube at one end through nozzles or holes, at velocities close to the
172:
35:
thought of the idea for isotope separation and tried creating such a device in 1934 in the lab of
92:
cut (the ratio of product flow to feed flow) of about 1/20, and high process-operating pressures.
116:
101:
246:
164:
133:
112:
76:
8:
260:
165:
225:
138:
217:
176:
296:
209:
60:
24:
105:
84:
275:
221:
143:
36:
40:
44:
28:
229:
197:
64:
32:
213:
56:
96:
80:
88:
47:
content of around 3–5%, and 80–93% enriched uranium for use in
59:(known as the 'Y' plant) to produce hundreds of kilograms of
52:
196:
de
Villiers, J. W.; Jardine, Roger; Reiss, Mitchell (1993).
252:
Uranium
Enrichment Technologies: Proliferation Implications
266:
53:
The
Uranium Enrichment Corporation of South Africa, Ltd.
195:
55:(UCOR) developed the process, operating a facility at
273:
167:The Strangest Man: The Hidden Life of Paul Dirac
75:In the vortex separation process a mixture of
129:South Africa and weapons of mass destruction
247:Aerodynamic Process for Uranium Enrichment
27:process designed around a device called a
111:Advantages of this process are a lack of
162:
274:
263:Web Archives (archived 2001-09-27)
257:South Africa's Nuclear Weapons Program
16:Aerodynamic uranium enrichment process
198:"Why South Africa Gave up the Bomb"
13:
302:Nuclear technology in South Africa
171:. New York: Basic Books. pp.
43:for producing reactor fuel with a
14:
318:
267:Sa Companies currently enrichment
240:
21:Helikon vortex separation process
175:-9, 307, 311, 313–4, 321, 431.
95:Due to the extremely difficult
189:
156:
1:
149:
117:nuclear proliferation concern
7:
122:
10:
323:
70:
307:South African inventions
163:Farmelo, Graham (2009).
102:axial-flow compressors
134:Nuclear reprocessing
113:criticality concerns
77:uranium hexafluoride
261:Library of Congress
292:Isotope separation
282:Nuclear technology
139:Nuclear fuel cycle
25:uranium enrichment
23:is an aerodynamic
287:Nuclear materials
182:978-0-465-02210-6
314:
234:
233:
214:10.2307/20045817
193:
187:
186:
170:
160:
322:
321:
317:
316:
315:
313:
312:
311:
272:
271:
243:
238:
237:
202:Foreign Affairs
194:
190:
183:
161:
157:
152:
125:
106:heat exchangers
73:
49:nuclear weapons
17:
12:
11:
5:
320:
310:
309:
304:
299:
294:
289:
284:
270:
269:
264:
254:
249:
242:
241:External links
239:
236:
235:
188:
181:
154:
153:
151:
148:
147:
146:
141:
136:
131:
124:
121:
85:speed of sound
72:
69:
15:
9:
6:
4:
3:
2:
319:
308:
305:
303:
300:
298:
295:
293:
290:
288:
285:
283:
280:
279:
277:
268:
265:
262:
258:
255:
253:
250:
248:
245:
244:
231:
227:
223:
219:
215:
211:
208:(5): 98–109.
207:
203:
199:
192:
184:
178:
174:
169:
168:
159:
155:
145:
144:Nuclear power
142:
140:
137:
135:
132:
130:
127:
126:
120:
118:
114:
109:
107:
103:
98:
93:
90:
86:
82:
78:
68:
66:
62:
58:
54:
50:
46:
42:
38:
37:Peter Kapitza
34:
30:
26:
22:
205:
201:
191:
166:
158:
110:
94:
74:
41:South Africa
20:
18:
45:uranium-235
29:vortex tube
276:Categories
150:References
65:waste heat
33:Paul Dirac
222:0015-7120
57:Pelindaba
230:20045817
123:See also
97:plumbing
89:isotopic
81:hydrogen
79:gas and
297:Uranium
259:at the
71:Process
228:
220:
179:
226:JSTOR
218:ISSN
177:ISBN
19:The
210:doi
173:248
61:HEU
278::
224:.
216:.
206:72
204:.
200:.
119:.
108:.
51:.
31:.
232:.
212::
185:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.