1、Designation: C1838 16Standard Practice forCleaning for 1S and 2S Bottles1This standard is issued under the fixed designation C1838; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses
2、indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice provides a description of the differentways to clean uranium hexafluoride (UF6) bottles.1.2 This practice describes two kinds of sample bottles
3、: 1Sand 2S bottles.1.3 UnitsThe values stated in SI units are to be regardedas the standard. No other units of measurement are included inthis standard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of thi
4、s standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C787 Specification for Uranium Hexafluoride for Enrich-mentC859 Terminology Relating to Nuclear MaterialsC996 Specificat
5、ion for Uranium Hexafluoride Enriched toLess Than 5 %235U2.2 ANSI Standard:3N14.1 Nuclear MaterialsUranium HexafluoridePackaging for Transport3. Terminology3.1 DefinitionsDefinitions of terms are as given in Termi-nology C859.4. Significance and Use4.1 The uranium hexfluoride (UF6), as described in
6、Speci-fications C787 and C996, has to meet different requirements:one set of requirements being safety, health physics, andcriticality and the other set being chemical, physical, andisotopic. To ensure the UF6is in compliance with allrequirements, sampling and analysis shall be performed.Therefore,
7、packaging may have a significant impact on thequality of UF6.4.2 After sampling, the bottle will contain residues. There iscontamination because of the equipment, other contaminationcaused by nonvolatile elements, and isotopic contamination asa result of UF6hydrolysis.4.3 Cleaning shall be efficient
8、. Special emphasis should begiven to decontaminate the bottles without leaving any trace ofcleaning products, make the bottles inert in UF6medium(passivation bottle), and minimize waste. The cleaning processshould be easy, safe, and environmentally friendly.4.4 This practice describes different prot
9、ocols for cleaningbottles by gas and liquid.5. Description of Sample Bottles5.1 Abottle is composed of a cylinder, adaptors, and a valve(see Fig. 1).5.2 Adaptors are brazed or welded on the valve and screwedon the cylinder.5.3 Bottles and valves are made from nickel or nickel-copper alloy (for examp
10、le, Monel).5.4 The design pressure and temperature are indicated inANSI N14.1.6. Reagents6.1 Purity of ReagentsReagent-grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents conform to the specifications of the Committee onAnalytical Reagents of the Am
11、erican Chemical Society wheresuch specifications are available.4Other grades may be used,provided it is first ascertained that the reagent is of sufficiently1This practice is under the jurisdiction of ASTM Committee C26 on NuclearFuel Cycle and is the direct responsibility of Subcommittee C26.02 on
12、Fuel andFertile Material Specifications.Current edition approved April 1, 2016. Published May 2016. DOI: 10.1520/C183816.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refe
13、r to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.4Reagent Chemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For sugge
14、stions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K. and the United States Pharmacopeia andNational Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.Copyright ASTM International,
15、100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1high purity to permit its use without lessening the effectivenessof the cleaning process.6.2 Chlorine Trifluoride (ClF3):6.2.1 CompositionSee Table 1.6.2.2 HazardsClF3is a highly reactive agent. With water,it forms h
16、ydrofluoric acid that penetrates the skin causingdestruction of deep tissue layers. It is very corrosive and toxicby inhalation or contact. It is a powerful oxidizer that maintainsthe combustion and reacts violently with organic compounds.6.3 Fluorine Gas (F2):6.3.1 CompositionFluorine gas used is p
17、ure.6.3.2 HazardsFluorine gas is extremely corrosive andtoxic. The free element has a characteristic pungent odor and isdetectable in concentrations as low as 20 ppb, which is belowthe safe working level. Exposure to low concentrations causeseye and lung irritation.6.4 Mixture of Hydrofluoric Acid,
18、Sulfuric Acid, andChrome Trioxide:6.4.1 CompositionSee Table 2.6.4.2 HazardsThis mixture is a corrosive and an oxidant.It is toxic by inhalation, contact, and ingestion. It is acarcinogenic compound.6.5 Phosphoric Acid:6.5.1 CompositionPhosphoric acid is used at about 1mol.L-1.6.5.2 HazardsCorrosive
19、 reagent and it causes burns.6.6 Potassium Carbonate (K2CO3) and Sodium Carbonate(Na2CO3):6.6.1 CompositionThe concentration specified is about100gK2CO3/L.6.6.2 HazardsIrritation and corrosion of the skin, theeyes, and the respiratory and digestive tracts.6.7 Hydrogen Peroxide (H2O2):6.7.1 Compositi
20、onThe concentration specified is about 1to 4 % H2O2.6.7.2 HazardsStrong oxidizer, corrosive to the eyes, andcauses severe burns.6.8 Citric Acid:6.8.1 CompositionThe concentration specified is about150 g/L.6.8.2 HazardsCitric acid can cause severe eye irritationand possible injury.6.9 Nitric Acid:6.9
21、.1 CompositionThe concentration specified is about0.01 mol/L.6.9.2 HazardsNitric acid is a corrosive chemical andcontact can severely irritate and burn the skin and eyes.6.10 Acetic Acid:6.10.1 CompositionNo concentration specified.6.10.2 HazardsCauses severe eye irritation. Contact withliquid or va
22、por causes severe burns and possible irreversibleeye damage.7. Gaseous Cleaning7.1 Emptying the Bottles:7.1.1 The bottles are connected to a cleaning manifoldinside a heating enclosure.7.1.2 The equipment is tested to ensure vacuum integrity.The valves are opened.7.1.3 The enclosure is heated to 70C
23、 for approximately 2 h.The manifold is pumped at 10 Pa abs for approximately 1 h.7.1.4 The bottles are filled with nitrogen to 400 kPa abs andpumped as in 7.1.3.7.1.5 These operations are repeated twice.7.2 ClF3Treatment:7.2.1 The bottles are filled with ClF3at 15 kPa abs. Thislasts approximately 1
24、h.7.2.2 The bottles are emptied by pumping at 10 Pa abs forapproximately 1 h.7.2.3 The bottles are filled for a second time at 15 kPa absand treated for approximately 2 h.7.2.4 The bottles are then emptied as in 7.2.2.7.2.5 The bottles are disconnected at room temperature andmay be used for sampling
25、.7.3 F2Treatment:7.3.1 The bottles are filled at 100 kPa abs with differentconcentrations of F2in N2.FIG. 1 1S and 2S BottlesTABLE 1 ClF3CompositionClF397 % (molar)HF #0.2 % (molar)ClF #1 % (molar)Cl2#0.5 % (molar)ClO2FClO3F #0.05 % (molar)TABLE 2 Chrome Trioxide, Sulfuric Acid, and Hydrofluoric Aci
26、dCompositionChrome Trioxide CrO3% (in weight)5to10Sulfuric Acid H2SO45to15Hydrofluoric Acid HF 1 to 7C1838 1627.3.2 The first treatment is performed at 10 % of F2.7.3.3 The last treatment is performed at 100 % of F2.7.3.4 Between each treatment, the bottles are emptied bypumping at 10 Pa abs.8. Liqu
27、id Cleaning8.1 Operations before Washing:8.1.1 External CleaningUse a solvent for degreasing andcleaning.8.1.2 Bottle Dismantling:8.1.2.1 The bottles are drained.8.1.2.2 The bottles are placed in a vise and the valveloosened to finger tightness.8.1.2.3 The bottles are frozen for approximately 1 min
28、inliquid nitrogen.8.1.2.4 The valves are removed from the bottles.8.2 Operations after Washing:8.2.1 Flushing and Drying:8.2.1.1 The liquid is decanted from the bottles and thevalves in a waste container.8.2.1.2 The bottles and the valves are rinsed with deminer-alized water. The liquid is decanted
29、into a waste container.8.2.1.3 The bottles and the valves are dried, inside andoutside, using inert gas and a heating enclosure.8.2.1.4 The internal surfaces of the dried bottles are in-spected. If needed, repeat cleaning.8.2.2 Bottle Assembling:8.2.2.1 A lubricant suited for use with UF6or polytetr
30、afluo-roethylene tape is placed on the bottle thread to obtain a sealwith the valves.8.2.2.2 The bottles are assembled.8.2.3 Control of the Tightness:8.2.3.1 This control includes:(1) An internal and external inspection,(2) A hydrostatic test,(3) A leak test of valves and caps, and(4) A test of the
31、thickness of walls if the corrosion issignificant.8.2.3.2 All the objectives of the control are described inANSI N14.1.8.3 Washing Process:8.3.1 Washing Sequences with Sodium Carbonate and Mix-ture of Hydrofluoric Acid, Sulfuric Acid, and Chrome TrioxideCleaning:8.3.1.1 The bottles are soaked in a b
32、asic (Na2CO3) bath.8.3.1.2 The bottles are rinsed with water.8.3.1.3 The bottles are soaked in the mixture for 1 to 3 min,depending on state.8.3.1.4 The bottles are rinsed with demineralized water.8.3.1.5 The bottles are soaked in ethyl alcohol.8.3.2 Washing Sequences with Phosphoric Acid and Potas-
33、sium Carbonate Cleaning:8.3.2.1 The bottles are rinsed with water and tripolyphos-phate under pressure (150 kPa, 80C).8.3.2.2 The bottles are rinsed with demineralized water.8.3.2.3 The bottles are soaked in a basic (K2CO3) bath.8.3.2.4 The bottles are rinsed with water.8.3.2.5 The bottles are soake
34、d in an acid bath (phosphoricacid smear).8.3.2.6 The bottles are rinsed with water.8.3.3 Washing Sequences with Potassium Carbonate andHydrogen Peroxide Cleaning:8.3.3.1 The bottles are evacuated.8.3.3.2 The solution is introduced in the bottle. There is novalve dismantling.8.3.3.3 The bottles are i
35、nverted and shaken for about 2 to 3min.8.3.3.4 The solution is emptied using vacuum.8.3.3.5 This method is repeated four to five times until thewash solution is clear.8.3.3.6 The bottles are rinsed with deionized water fourtimes in the same fashion.8.3.4 Washing Sequences with Citric Acid (Nitric Ac
36、id)Cleaning:8.3.4.1 The bottles are placed upside down in a citric acidcontainer and are gently tapped with a wooden mallet todislodge any loose material.8.3.4.2 The vacuum is removed from the valves and then thevalves are opened.8.3.4.3 All of the bottles components are placed in a tray ofwater to
37、await decontamination.8.3.4.4 The bottles are filled with citric acid.8.3.4.5 A rubber bung is placed in the bottle neck. Thebottles are shaken well for 10 s, then allowed to stand for 30min.8.3.4.6 The valves are removed from the tray and water isrun through to confirm that there is no blockage.8.3
38、.4.7 The valves are connected to form a vertical chain.8.3.4.8 A pump outlet pipe is connected to the top of thechain. A pump inlet pipe is immersed into a stainless steelbeaker containing a citric acid.8.3.4.9 The liquid circulates for 1 h.8.3.4.10 If the citric acid turns yellow, then replace with
39、fresh solution.8.3.4.11 Nitric acid could be used in place of citric acid, butthe concentration and the treatment period shall be shorter toreduce the corrosion effect.8.3.5 Washing Sequences with Acetic Acid Solution andSodium Carbonate with Hydrogen Peroxide Cleaning Method:8.3.5.1 The bottles are
40、 connected to the system.8.3.5.2 The bottles are drained.8.3.5.3 The bottles are rinsed with a decontamination solu-tion (sodium carbonate with hydrogen peroxide) for 30 minand drained.8.3.5.4 The bottles are rinsed with hot water for approxi-mately 2 min and drained.8.3.5.5 The bottles are rinsed w
41、ith acetic acid solution forapproximately 2 min and drained.8.3.5.6 The bottles are rinsed with hot water for three cyclesof approximately 2 min and drained.9. Choice of Treatment9.1 Performance:9.1.1 Carbonates are decontaminants known in the nuclearfield.C1838 1639.1.2 Acids are powerful reagents
42、for decontamination.9.1.3 Hydrogen peroxide is used as a supplement to otherreagents to aid with the oxidation of uranium IV.9.1.4 ClF3is very reactive and allows, at the same time, toeliminate impurities and passivate the metal of the bottle.9.2 Process Comparison (see Table 3):9.2.1 Gaseous treatm
43、ents are easier to operate because theydo not require dismantling of the bottle.9.2.2 Liquid treatments require more time.9.3 Hazards:9.3.1 ClF3is a chemical that is extremely dangerous to use.9.3.2 Acids and hydrogen peroxide are corrosive and toxicbut their use is mastered well in the industry.9.3
44、.3 Carbonates present little risks.9.4 Effluents:9.4.1 For ClF3treatment, little product is used. Effluents arewashed in a scrubber.9.4.2 Liquid treatments generate more effluents. These re-agents are commonly used in the industry. The management ofeffluents remains accessible.9.4.3 The mixture of h
45、ydrofluoric acid, sulfuric acid, andchrome trioxide is very corrosive and hazardous to the envi-ronment. This reagent requires a specific additional treatment.10. Keywords10.1 1S 2S bottle cleaning; UF6C1838 164ASTM International takes no position respecting the validity of any patent rights asserte
46、d in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by th
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48、careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM Internat
49、ional, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 3 Comparison ProcessReagent Deconta
