1、Item No. 24057 NACE International Publication 5A171 (2007 Edition) This Technical Committee Report has been prepared by NACE International Task Group 358* on Hydrofluoric Acid and Hydrogen Fluoride: Review of NACE Publication 5A171. Materials for Storing and Handling Commercial Grades of Aqueous Hyd
2、rofluoric Acid and Anhydrous Hydrogen Fluoride December 2007, NACE International This NACE International technical committee report represents a consensus of those individual members who have reviewed this document, its scope, and provisions. Its acceptance does not in any respect preclude anyone fr
3、om manufacturing, marketing, purchasing, or using products, processes, or procedures not included in this report. Nothing contained in this NACE International report is to be construed as granting any right, by implication or otherwise, to manufacture, sell, or use in connection with any method, app
4、aratus, or product covered by Letters Patent, or as indemnifying or protecting anyone against liability for infringement of Letters Patent. This report should in no way be interpreted as a restriction on the use of better procedures or materials not discussed herein. Neither is this report intended
5、to apply in all cases relating to the subject. Unpredictable circumstances may negate the usefulness of this report in specific instances. NACE International assumes no responsibility for the interpretation or use of this report by other parties. Users of this NACE International report are responsib
6、le for reviewing appropriate health, safety, and regulatory documents and for determining their applicability in relation to this report prior to its use. This NACE International report may not necessarily address all potential health and safety problems or environmental hazards associated with the
7、use of materials, equipment, and/or operations detailed or referred to within this report. Users of this NACE International report are also responsible for establishing appropriate health, safety, and environmental protection practices, in consultation with appropriate regulatory authorities if nece
8、ssary, to achieve compliance with any existing applicable regulatory requirements prior to the use of this report. CAUTIONARY NOTICE: The user is cautioned to obtain the latest edition of this report. NACE International reports are subject to periodic review, and may be revised or withdrawn at any t
9、ime without prior notice. NACE reports are automatically withdrawn if more than 10 years old. Purchasers of NACE International reports may receive current information on all NACE International publications by contacting the NACE International FirstService Department, 1440 South Creek Drive, Houston,
10、 Texas 77084-4906 (telephone +1 281228-6200). FOREWORD This NACE International technical committee report presents general information on materials commonly used for storing and handling commercial grades of aqueous hydrofluoric acid (AqHF) and anhydrous hydrogen fluoride (AHF). Some materials gener
11、ally avoided are also discussed. This report is intended for end users, designers, and suppliers of equipment for use with AqHF and AHF. These include, among others, workers in process industry plants, engineering and construction designers, and suppliers of equipment such as pumps, valves, and hose
12、s. This information is useful for initial design and for cost estimates of equipment to handle most commercial AqHF and AHF. The report addresses AqHF and AHF purchased to normal commercial quality that do not contain impurities liable to affect their inherent corrosion characteristics. Testing in t
13、he service environment typically indicates a materials suitability for use with AqHF and AHF. This report does not include all materials that might be resistant and is not intended to limit the consideration and testing of other materials. The chemical symbol for hydrogen fluoride is HF. Throughout
14、this report, the term “HF” is used to mean the presence of hydrogen fluoride in any form or as a component in any stream. The term “AqHF” is used to mean a solution of some percentage of HF dissolved in water. If a percentage designation is associated with the term “AqHF,” it denotes the weight perc
15、entage concentration of HF in the water (aqueous) solution. The term “AHF” is used to mean a commercial grade of anhydrous HF as a liquefied gas with only specification levels of water present. The term “HF service” is used to mean AqHF and AHF services. It is recognized that both AqHF and AHF somet
16、imes exist in streams with organics or other materials present, which would change the apparent concentrations but have only small effects on the corrosiveness of the HF. In these cases, the context provides an understanding of the resulting effects. In this report, concentrations of solutions or al
17、loy compositions are understood to be weight percentages unless otherwise indicated. _ * Chair Herbert Jennings, DuPont Fluoroproducts, La Porte, TX. NACE International 1 NACE Publication 5A171 was originally prepared by NACE International Work Group T-5A-11b, a component of Task Group (TG) T-5A-11
18、and Unit Committee T-5A on Corrosion in Chemical Processes, and was published by NACE International in 1971. The report was revised in 1993 by TG T-5A-23, and in 1995 by TG T-5A-36. It was revised in 2001 by TG 140, administered by Specific Technology Group (STG) 36 on Process Industry: Materials Pe
19、rformance in Chemicals. This report was revised in 2007 by TG 358, administered by STG 36, and is also sponsored by STG 34 on Petroleum Refining and Gas Processing. It is published by NACE International under the auspices of STG 36. CAUTION: This NACE International technical committee report does no
20、t present standardized materials selection methods or materials specifications. This report presents information on current industry practices only and makes no recommendations on the use of materials. NACE technical committee reports are intended to convey technical information or state-of-the-art
21、knowledge regarding corrosion. In many cases, they discuss specific applications of corrosion mitigation technology, whether considered successful or not. Statements used to convey this information are factual and are provided to the reader as input and guidance for consideration when applying this
22、technology in the future. However, these statements are not intended to be recommendations for general application of this technology, and must not be construed as such. 2 NACE International 3 NACE International Publication 5A171 Materials for Storing and Handling Commercial Grades of Aqueous Hydrof
23、luoric Acid and Anhydrous Hydrogen Fluoride Contents Introduction 4 Safety 4 Materials Commonly Used 4 HF Manufacture 4 Storing and Handling 4 Materials CharacteristicsMetals and Alloys . 5 Aluminum and Its Alloys . 12 Carbon and Low-Alloy Steels . 12 Cast Irons . 14 Stainless Steels 14 Copper Alloy
24、s . 14 Nickel-Rich Alloys. 15 Nickel-Based Alloys 15 Reactive Metals 16 Precious Metals 16 Cast Alloys 16 Materials CharacteristicsNonmetallic Materials. 16 Organic Materials 18 Inorganic Materials . 19 References 20 Bibliography 22 Appendix A: Metals and Alloys Mentioned in Text 23 FIGURES Figure 1
25、. Metals and Alloys for HF Service: Regions Where Observed Corrosion 6 Rates Are 0.51 mm/y (20 mpy) or Less Figure 2. HF Corrosion Data for Carbon Steel at 21 to 38C (70 to 100F) 16 Figure 3: Corrosion of Carbon Steel in AHF Liquid and Vapor Over a Range of Temperatures 13 Figure 4: Stainless Steel,
26、 Nickel-Rich, and Nickel-Based Alloys for HF Service 15 Figure 5: Plastics and Elastomers in HF Service . 17 TABLES Table 1: Materials Commonly Used for Storing and Handling Commercial Grades 5 of AqHF and AHF Table 2: Corrosion Rate Data for Various Metals and Alloys in HF Service 7 NACE Internatio
27、nal 4 INTRODUCTION AqHF is commercially available in 49% and 70% solutions. Commercial AHF contains less than 400 parts per million by weight (ppmw) water. Although this report is intended as a guide for handling commercial grades of AqHF and AHF, additional information is given to aid users of AqHF
28、 and AHF who encounter other concentrations. It is assumed that purchased AqHF or AHF is received and stored at ambient temperature. When temperatures are not indicated, the data are considered valid for ambient temperatures with only intermittent service up to 49C (120F). When temperatures are indi
29、cated, the data are considered valid for long-term service up to that temperature. Corrosion rates at temperatures greater thanthose indicated sometimes are so high that service life is not economical or product contamination might be great. For critical design situations, more specific information
30、is obtained from producers of AqHF and AHF, materials manufacturers and suppliers, equipment fabricators, and process licensors. HF alkylation unit users can refer to API(1)RP 7511and Dobis et al.2Additional resource materials are listed in the Reference and Bibliography sections. Metals and alloys
31、mentioned in the text, tables, and figures are presented with their UNS(2)numbers in Appendix A. Where possible, UNS numbers are used throughout this report. SAFETY AqHF, AHF, and their vapors are extremely hazardous and sometimes cause painful burns and fatal edema of the lungs. The burns sometimes
32、 are not immediately painful or visible. Early treatment is generally advised. The National Institute of Occupational Safety and Health (NIOSH)(3)recommended exposure limit for HF is 3 parts per million (ppm) time weighted average (TWA) (8 h) with a maximum of 6 ppm (15 min).3Personal protective equ
33、ipment, convenient showers and eye wash stations, and first aid supplies specific to HF exposure are typical safety preparations emphasized by HF manufacturers to be available at user sites. Self-contained breathing apparatus are normally available in case of HF leaks. Packing materials, insulation,
34、 gaskets, and pump seals absorb HF and are difficult to decontaminate. Any materials contaminated with HF are generally treated as hazardous. Corrosion products and other reaction products of HF are potentially hazardous, even when apparently dry. Personal safety measures and first aid are covered i
35、n “Medical Management Guidelines for Acute Chemical Exposures,”4in HF manufacturers bulletins, and in Material Safety Data Sheets. MATERIALS COMMONLY USED HF Manufacture Both experience and laboratory research5have shown that nickel (Ni)-based alloys containing chromium (Cr), molybdenum (Mo), and co
36、pper (Cu) have the greatest corrosion resistance to mixtures of concentrated sulfuric acid and HF commonly found in HF manufacture. Alloys in this class include UNS N06030, N06985, N08007, N08020, and N08825. UNS N10276 and N26455 have been used for premixing equipment and as a lining in reactor she
37、lls. Some HF manufacturers have reactors and kilns made of carbon steel. Carbon steel is used primarily for AHFprocess and storage equipment at temperatures less than 66C (150F). Storing and Handling Materials in Table 1 are commonly used for storing and handling commercial grades of AqHF and AHF, w
38、hich implies the AqHF and AHF are at ambient temperature, are low in oxygen or other contaminants, and are in no-flow or low-flow conditions. Ambient temperatures sometimes vary widely and affect the rate of corrosion or attack on materials. Therefore, the information in Table 1 is intended for use
39、in conjunction with Figures 1 through 5. _ (1)American Petroleum Institute (API), 1220 L Street NW, Washington, DC 20005-4070. (2)Metals and Alloys in the Unified Numbering System (UNS), a joint activity of ASTM International (ASTM), 100 Barr Harbor Dr., West Conshohocken, PA 19428-2959, and SAE Int
40、ernational (SAE), 400 Commonwealth Drive, Warrendale, PA 15096-0001. (3)National Institute for Occupational Safety and Health (NIOSH), Patriots Plaza Bldg., 395 E Street SW, Washington, DC 20201. NACE International 5 Table 1 Materials Commonly Used for Storing and Handling Commercial Grades of AqHF
41、and AHF(A), (B)Equipment AHF70% AqHF 49% AqHF Stationary tanks Steel(C)66C (150F) Steel(C)32C (90F); pure chlorobutyl(I)- or fluoroplastic-lined steel Pure chlorobutyl(I)- or fluoroplastic-lined steel Tank trucks Steel(C)ambient Steel(C); pure chlorobutyl(I)- or fluoroplastic-lined steel Pure chloro
42、butyl(I)- or fluoroplastic-lined steel Rail tank cars Steel(C)ambient Steel(C); pure chlorobutyl(I)- or fluoroplastic-lined steel Pure chlorobutyl(I)- or fluoroplastic-lined steel Piping Steel(D)66C (150F) Steel(C)or fluoroplastic-lined steel Polypropylene- or fluoroplastic-lined steel Pumps UNS J92
43、800 (CF3M), J92900 (CF8M), N24135 (M35-1),(E)or N08007 (CN7M) Fluoroplastic-lined steel or UNS N24135(E)Fluoroplastic-lined steel Valves Steel (with UNS N04400 and N24135 trim), UNS J92800, J92900, N24135,(E)or N08007 (CN7M) Fluoroplastic-lined steel or UNS N24135(E)Fluoroplastic-lined steel Gaskets
44、 Fluoroplastic(F)Fluoroplastic(F)Fluoroplastic(F)Hoses Fluoroplastic-lined(G) Fluoroplastic-lined(G)Fluoroplastic-lined(G)Bolting Alloy steel(H)Alloy steel(H)Alloy steel(H)(A)Appendix A lists common names of metals and alloys with their corresponding UNS numbers. (B) Temperatures following the mater
45、ial indicate maximum temperatures that have resulted in successful service. (C)The subsection of this report titled Carbon and Low-Alloy Steels has information on steel cleanliness and hardness control. Pressure vessel and piping design is normally in accordance with appropriate local and national c
46、odes and standards that ensure material and fabrication quality and safety of design. (D)Typically heavy-wall UNS K03006, Schedule 80 or higher nominal wall thickness (according to ANSI(4)Standard B36.106and ANSI Standard B36.197). (E)UNS N24130 (M30C) is sometimes used for AHF or high concentration
47、s of AqHF at ambient to moderate temperatures, but it has been attacked by AqHF with concentrations less than 70%. This alloys corrosion susceptibility is caused by the presence of niobium (Nb). (F)Perforated metal encapsulated in polytetrafluorethylene (PTFE) or sheet PTFE (with carbon or calcium f
48、luoride filler, or without filler), or spiral wound with PTFE or flexible graphite. (G)Stainless steel (SS) braiding and wire-reinforced rubber are sometimes used on fluoroplastic-lined hoses. (H)ASTM(5)A 1938grade B7M with supplementary requirement S3, ASTM A 193 grade B8M class 2, or ASTM A 3209gr
49、ade L7M (with hardness testing according to ASTM A 320, Paragraph 6.3), ASTM A 30710grade B, and UNS N10276 (flanges upstream from primary isolation valves in liquid service) are sometimes used. (I)“Pure chlorobutyl” means not blended with other polymers. MATERIALS CHARACTERISTICSMETALS AND ALLOYS The temperature and HF concentration conditions that define the regions wherein the corrosion rate does not exceed 0.51 mm/y (20 mil per year mpy) for a number of metals and alloys in HF service are shown in Figure 1.11
