材料和氧的兼容性

1、Materials and Oxygen Compatibility材料和氧的相容性材料和氧的相容性Plant Design & Operations for Industrial GasesProperties & Hazards of Oxygen氧的性质和危险氧的性质和危险 Oxygen is essential to the maintenance of life氧是维持生命的基本要素 Oxygen is essential for combustion氧是燃烧的基本要素 Oxygen is a reactive gas which will form oxides w

2、ith most elements.氧可同大多数元素反应生成氧化物Oxygen the ability of a material to coexist with both oxygen and a potential source(s) of ignition 一种材料同氧和潜在的点火一种材料同氧和潜在的点火源之间共存的能力。源之间共存的能力。What is Oxygen Compatibility?什么是氧相容性什么是氧相容性 within the acceptable risk parameter of the user 在使用者可接受的风险参数之内。在使用者可接受的风险参数之内。 (a

3、s the material will most likely burn in oxygen, the level of risk that one is willing to accept must be taken into account)（必须考虑愿意接受的风险等级） 材料运作环境处于可接受的温度和压力下。 at an expected temperature and pressure (the environment that the material must operate in)Properties & Hazards of Oxygen 氧的性质和氧的性质和危险危险W

4、hat are the hazards ? Oxygen enhances burning of materials 氧加强材料的燃烧 the material burns more aggressively 材料更剧烈地燃烧 the fire cannot be extinguished火不能扑灭 All materials burn in oxygen except ceramics, gold and silver 除陶瓷、金和银之外，所有材料在氧中都会燃烧。 The energy required to start an ignition can be very small材料点燃所需

5、要的能量可以非常小。 Oxygen enrichment gives no warning 氧富集无任何先兆。Effect of adding LOX toa charcoal fire 液氧加木炭Why is oxygen compatibility important?氧相容性的重要性？氧相容性的重要性？Motherwell Tanker Pump Ignition1979（槽车泵起火）Pump was constructedof materials that were not compatible with oxygen泵的结构材料与氧不相容。ALUMINIUM PUMP铝泵铝泵Why

6、is oxygen compatibility important?氧相容性的重要性？氧相容性的重要性？During the 1970s there were numerous LOX pump fires. Byreplacing the aluminium bronze impeller and casing with a tin bronze material these ignitions were eliminated.70年代发生多次液氧泵起火事故。叶轮和泵壳材料用青铜取代铝青铜后得以消除。Where do incidents occur ?事故发生在何处？事故发生在何处？Why

7、is oxygen compatibility important?氧相容性的重要性？氧相容性的重要性？ Cylinder filling 气瓶充装 Liquid oxygen pumps 液氧泵 Oxygen compressors 氧压缩机 Oxygen pipelines and valve systems 氧及液氧管路和阀门系统 LOX piping and valve systems In areas where exposure to oxygen can occur 有氧存在的场所So Where do Oxygen Hazards Exist ?氧的危险存在于：氧的危险存在于：

8、 In pressurised systems containing oxygen含有氧的压力系统中 In atmospheric air enriched with oxygen空气中的富氧气氛中Hazards of oxygen 氧的危险氧的危险Oxygen concentration 氧含量氧含量 25303540Probability of igniting clothing %Based on time to ignite denim overalls with acigarette. 衣服起火的可能性衣服起火的可能性5305090Probability of a fatal or

9、serious injury %Based on the burning rate of the material andreaction time of the victim. 死亡或重伤的可能性死亡或重伤的可能性10162990Combined probability of a fatal orserious injury % 死亡或重伤的组合可能性死亡或重伤的组合可能性0.54.814.581Hazards of oxygen in air 空气中氧的危险空气中氧的危险How much oxygen does it take to create a hazard ?(% in air)W

10、here Do You Find Oxygen Enrichment ?什么地方容易产生富氧？什么地方容易产生富氧？ Oxygen enrichment hazards in air must be considered at oxygen percentages of 25% and above. 氧含量达25%以上必须考虑富氧的危险 Oxygen is denser than air and so can collect in pits, ducts, trenches, etc. 氧较空气重，因而可能聚集在坑、洞及沟渠等处。Hazards of oxygen 氧的危险氧的危险 LOX m

11、ay form on contact of air with LIN. 同液氮（同液氮（LIN）接触的空气可能会形成液氧（接触的空气可能会形成液氧（LOX）。）。a liquid oxygen release occurred during vessel filling 储罐充装时发生液氧泄漏。liquid oxygen can travel long distances down inclines because it is very dense由于比重大，液氧可沿坡度向下流动到远处。a car caught fire but the occupants escaped 汽车起火，人员来不及

12、逃走。Oxygen Enrichment富氧气氛富氧气氛 VIE/Tanker Slope 储罐储罐/槽车槽车/坡度坡度1989年/富氧气雾中汽车起火Claymont plant, Ohio 某工厂defective and undersized liquid disposal system 废液排放设施容量不足并有缺陷。large cloud of oxygen enriched air formed 形成大量富氧气雾。car drove into cloud 汽车进入气雾，突然爆发大火。car burst into flamesdriver had narrow escape 司机勉强逃生

13、。Oxygen Enrichment 富氧气氛富氧气氛Car fire in Oxygen Enriched Cloud 1989Oxygen 氧氧 Particle Impact 微粒碰撞微粒碰撞 Contamination 污染污染 Heat of Compression 压缩热压缩热 Friction 摩擦摩擦All materials in contact with oxygen 与氧接触的所有材料与氧接触的所有材料Fire Triangle 燃烧三角形燃烧三角形Managing Risks in Oxygen Systems 氧系统的风险管理氧系统的风险管理Fuel 燃料燃料Igni

14、tionSource点火源点火源 Pressure 压力压力 Temperature 温度温度Concentration浓度浓度Careful selection of system materials - avoid fuels仔细选择系统材料-避免燃料。Good system/equipment design - avoid ignition sources良好的系统/设备设计-避免点火源。Good standards of cleanliness during construction and maintenance - avoid fuels and ignition sources

15、(absence of particulate matter and hydrocarbon oils and greases) 在制造和维修时采用标准的清洗程序-避免燃料和点火源（清除微粒和碳氢化合物的油和脂）。Good system commissioning - avoid ignition sources符合标准的投入程序-避免点火源。Good system maintenance - avoid ignition sources良好的维护规范-避免点火源。Operation within the systems declared safe operating limits - avo

16、id fuels and ignition sources 在系统明确的安全运行限度内使用-避免燃料和点火源。Managing Risks in Oxygen Systems氧系统的风险管理氧系统的风险管理How to Avoid Fires 怎样避免起火怎样避免起火Common Ignition Mechanisms点火机理点火机理 Common Ignition mechanisms普通的点火机理普通的点火机理 Temperature 温度 Friction 摩擦 Heat of compression 压缩发热 Promoted combustion (contaminate promo

17、tion) 触发燃烧（污染触发） Particle impact 微粒碰撞 Mechanical (mass) impact 机械碰撞 Occurred 1997, 5 Fatalities 1997年，5人死亡 Occurred following maintenance work on pressure reducing station 发生在（氧气）减压站维修之后。 Pressure relief valve had been installed following maintenance and system was being brought on-line when acciden

18、t occurred 维修后安全阀已装，系统正在投入。 All men located within a small building which enclosed pressure reducing station 所有人员都在减压站的小房内。 Operating conditions 25 barg to 10 barg, 100% O2 Stainless steel materials throughout 全部为不锈钢材料。 Paper filter element with stainless steel mesh support used on inlet to pressure

19、 reducing valve 减压阀前使用不锈钢网支撑的纸质过滤元件。Common Ignition Mechanisms点火机理点火机理Huta Batory Incident HB事故事故 Likely chain of events: 事故链分析： system put on line following maintenance 维修后投入。 rapid opening of valve caused rapid compression on piping section to 25barg 阀门快开使管内迅速压缩到25巴。 this adiabatic compression res

20、ulted in an instantaneous heating to 460oC (see equation in course notes) 这一绝热压缩在瞬间加热到460度（见过程方程） the paper element exceeded its auto ignition temp (AIT) and it burned, releasing heat 超过其自点燃温度，纸质元件燃烧并释放热量。 particles and contamination trapped by the filter also burned releasing more heat 扑集在过滤器上的微粒和污

21、物同时燃烧，放出更多的热量。 this resulted in the stainless steel piping materials burning fiercely 结果造成不锈钢管道材料剧烈的燃烧。 all these events took place very quickly 这一切都在瞬间。Common Ignition MechanismsHuta Batory Incident HB事故事故 Since the reducing station was in a building, all 5 men were unable to escape the violent fir

22、e and were killed 由于减压站位于建筑内，5个人都没能从大火中逃生。 The only clothing left on the men were their leather belts and boots 人身上只留下他们的皮带和皮靴。 For the want of a properly specified filter, 5 men died 因为过滤器的问题，5个人牺牲。 Some other thoughts: 其他的思考： BOC select filter materials very carefully 慎选滤材。 BOC would not use stain

23、less steel for this application BOC do not put buildings around pressure reducing stations 减压站不用不锈钢；不置于建筑内。 valves need to be chosen so that rapid pressurisation of piping legs is not possible 使用防止快速升压的阀门。Common Ignition MechanismsHuta Batory Incident HB事故事故 Use only approved materials 使用经核准的材使用经核准的

24、材料料Lessons From This Incident 事故教训事故教训 Consider consequences of incidents and escape routes in the design 在设计时应考虑事故的在设计时应考虑事故的可能性和逃离路线可能性和逃离路线 Do not substitute one material for another 材料不得随意替代材料不得随意替代 Always replace like for like 用相同的零件替换用相同的零件替换 Pressurise systems slowly 系统缓慢地升压系统缓慢地升压Examples of

25、 Good & Bad MaterialsRanking of Metals “好好”、“坏坏”金属材料金属材料ASTM/NASAASTM/NASAASTM/NASAUCC LindeParticle ImpactFriction/RubbingPromoted IgnitionPromoted IgnitionMonel 400NickelNickelNickel 200Tin BronzeInconel 600CopperMonel 400Yellow BrassTin BronzeMonel 400Monel K500Inconel 600Nodular Cast IronTin

26、 BronzeCopper7% Al. Bronze13-4 Stainless SteelYellow Brass90-10 CupronickelInconel 625Monel K500Red Brass70-30 CupronickelInconel 718Monel 400Inconel 600Tin BronzeNodular Cast IronLeaded Tin BronzeInconel 625Inconel 600Incoloy 800AISI 4140 Steel17-4 PH SteelInconel 625316 Stainless SteelHastelloy XI

27、ncoloy 800Hastelloy C-22304 Stainless Steel14-5 PH Steel321 Stainless SteelInconel 62513-4 Stainless SteelYellow Brass316 Stainless SteelHastelloy G-3014-5 Stainless Steel304 Stainless Steel304 Stainless Steel410 Stainless Steel410 Stainless SteelInconel 718316 Stainless Steel17-4 PH SteelNodular Ca

28、st Iron304 Stainless Steel7% Al. Bronze9% Nickel Steel17-4 PH SteelCarbon Steel7% Al. BronzeCarbon Steel6061 Al. Alloy6061 Al.AlloyAluminum BronzesExamples of Good & Bad MaterialsRanking of Non-Metals “好好”、“坏坏”非金属材料非金属材料NONMETALAUTOIGNITIONTEMPERATURE (0C)PTFEVespel SP-21Kel-FViton ANeoprene GRT

29、Krytox 240 ACHydraulic fluidNylon 6/6427420400-405268166427190160Ignition temperature was measured by electrical resistance heating of wires at 0 psig oxygen pressure 自点火温度，通过电阻加热丝，在氧压力为零表压下测量。 非金属材料 自点火温度The Application Determines the Material 按应用场合决定材料按应用场合决定材料Materials need to be selected for the

30、 application Aluminium is suitable for ASU vessels, columns and trays. It can be used for high pressure cylinders. 铝适用于空分的塔器及高压气瓶 Aluminium is not suitable for rotating machinery and valves. 铝不适用于转动机械、阀 Aluminium burns explosively in oxygen. 铝在氧中爆燃Aluminium dust is one of the most highly reactive (e

31、xplosive)metal dusts with oxygen 铝粉与氧会剧烈反应（爆炸）铝粉与氧会剧烈反应（爆炸）ASU column (200 tpd) used to stand on this spot 原空分塔位置原空分塔位置The Importance of Cleanliness 清洁的重要性清洁的重要性The remains of a grease was found in this cylinder 该气瓶发现油脂残留遗迹该气瓶发现油脂残留遗迹Highveld Valve Ignition Causes:高位阀点火原因：Inadequate degreasing &

32、 blow through procedures.脱脂和吹除不足Debris in the valve cage & filter 阀体及过滤器内有碎片High velocity impact or friction caused by valve movement 阀门动作引起高速碰撞或摩擦thin sections in the valve cage 阀体中有薄弱部分The Importance of Cleanliness 清洁的重要性清洁的重要性The Importance of CleanlinessWhat is Oxygen Clean ? 什么是什么是“氧清洁氧清洁”？

33、 No visible evidence of: 不得有下列可见遗迹：不得有下列可见遗迹： Moisture 水分 Cleaning agents 清洁剂 Flux residues / weld splatter 焊药/焊渣 Particulate matter 微粒 Organic materials e.g. oil, grease, paint etc. 有机物，如油、油脂、油漆等Cleaning for Oxygen Service How to Clean 如何作到如何作到“氧清洁氧清洁” Solvent degreasing 溶剂脱脂溶剂脱脂 Wiping with a lint

34、 free cloth 用非棉织物擦拭 Immersion in a solvent tank 在溶剂槽中浸泡 Cold washing 冷洗涤 Spraying/brushing 喷射/拭刷 Vapour phase circulation 蒸汽循环 Detergent cleaning 清洁剂清洗清洁剂清洗 Immersion 浸泡 Re-circulation 循环 Spraying/brushing 喷射/拭刷 Steam/Hot Water Cleaning 热水热水/蒸汽清洗蒸汽清洗 Pressurised cleaning of major plant parts and pip

35、es 装置主要部件和管道的压力清洗 With or without detergent 用或不用清洁剂 Common degreasing agents in use in BOC are halogenated solvents 通常使用的脱脂剂为卤化物溶剂： Trichloroethylene (TCE/Trike) 三氯乙烯 C2HCl3 Methylene Chloride (MC/MECL) 二氯甲烷 CH2Cl2 Perchloroethylene (Perc) 全氯乙烯 C2Cl4Cleaning for Oxygen Service Degreasing Agents 脱脂剂脱

36、脂剂 Solvent properties 溶剂的性质 Volatile, may produce dangerous levels of vapour 易挥发性 Hazards are from inhalation of vapour and from skin and eye contact 蒸汽吸入及皮肤和眼睛接触引起的危险 Can be unstable and decompose with metals e.g. newly machined aluminium 不稳定，腐蚀金属（如刚机加工的铝） Non-flammable in air but can decompose wit

37、h high temperatures to form acidic and toxic gases. 高温分解有毒Cleaning for Oxygen ServiceInspection Techniques 检查方法检查方法 Visual inspection with natural or white light 用自然光或白光进行检查 Visual inspection with a UV light 用紫外光进行检查 Wipe test (cloth or filter paper) 擦拭检验（布或滤纸） Solvent wash analysis 溶剂洗涤分析Flammabili

38、ty of cleaning agents in oxygen 清洗剂在氧中的可燃性清洗剂在氧中的可燃性 Trike left in pump following cleaning 清洗后三氯乙烯留在泵内 Pump started on liquid oxygen 泵（带液氧）启动 Explosion destroyed pump and piping 爆炸毁坏泵及管路Common Causes of Incidents事故原因事故原因System Inadequate 系统不足系统不足 Inadequate design 不适当的设计 Adiabatic compression 绝热压缩 D

39、ead ends 无余隙 Impingement areas 冲击区域 Cylinder valve spindles 气瓶阀芯 Using improper materials 使用不适当的材料 PTFE in medical systems 聚四氟乙烯用于医疗系统 Stainless Steel cylinder valve spindles 不锈钢瓶阀芯 Stainless Steel filters in medical oxygen regulators 医用氧调节器用不锈钢过滤器 Aluminium bronze pump components 铝青铜的泵部件 Aluminium

40、bodied regulators 调节阀阀体用铝Common Causes of Incidents事故原因事故原因System Inadequate系统不足系统不足A stainless steel filter was used in the suction line to the ground mounted LOX pump. A piece of the filter became detached and went into the pump causing an ignition. 安装在地上的液氧泵，吸入管上使用了一个不锈钢过滤器。过滤器碎片进入泵引起点火。安装在地上的液氧泵

41、，吸入管上使用了一个不锈钢过滤器。过滤器碎片进入泵引起点火。Using Improper Materials 使用不适当的材料使用不适当的材料 Approved materials used in the wrong applications1 批准的材料用于错误的场合 Stainless steels in high pressure applications 不锈钢用于高压 Unapproved greases in oxygen applications2 未经核准的油脂用于氧Common Causes of Incidents事故原因事故原因System Inadequate系统不足系

42、统不足 Lack of maintenance 缺乏维护 O-rings in cylinder filling 气瓶充装系统的O形环 Filters 过滤器 Changing soft materials in regulators, valves etc. 调节器，阀门等的软材料 Replacing worn parts 更换磨损的零件Common Causes of Incidents事故原因事故原因System Inadequate系统不足系统不足The soft goods (o-rings, seals etc) of this manifold cylinder fillingv

43、alve had never been replaced since the date of installation. 这个充瓶汇流排阀的软材料（这个充瓶汇流排阀的软材料（O-环，密封等）自安装后从未更换过。环，密封等）自安装后从未更换过。Lack of Maintenance 缺乏维护缺乏维护 Contamination 污染 Hydrocarbon greases & oils 碳氢化合物油脂或油类 Particles 颗粒 Debris on filters 过滤器的碎片 Solvent cleaners 溶剂清洗剂Common Causes of Incidents事故原因事

44、故原因System Inadequate系统不足系统不足 Lack of Knowledge 缺乏知识 Hyperbaric chamber in Milan had propane heaters 在米兰，高压氧仓有丙烷加热器 HMS Glasgow 格拉斯哥HMS Oil well equipment (5% O2 at 2200 psig) 油井设备（2200PSIG时5%氧） MCP master valve with silicone grease MCP主阀用硅脂Common Causes of Incidents事故原因事故原因Actions Inadequate行动不足行动不足

45、 Exchanging materials 调换材料 Using a white plastic for PTFE 用白塑料替换PTFE Monel looks the same as stainless steel 认为蒙乃尔(镍68%，铜28%，锰1.5%,铁2.5%)与不锈钢是一样的 Silicone grease for fluorinated greases 硅脂替换氟化脂Common Causes of Incidents事故原因事故原因Actions Inadequate行动不足行动不足 Improper operation 不适当的操作 Opening valves in wr

46、ong sequence 开阀顺序错误 Opening valves too quickly - cylinder filling 开阀太快充瓶时 Opening valve from high to low pressure 从高压到低压打开阀门 Allowing LOX pump to lose prime 液氧泵气蚀Common Causes of Incidents事故原因事故原因Actions Inadequate行动不足行动不足 Improper cleaning 不适当的清洁 Using paraffin in place of an approved solvent 用石蜡油替

47、代核准的溶剂 Leaving solvent in the system 将溶剂遗留在系统内 Purging systems with air/nitrogen 使用空气/氮气清洗系统Common Causes of Incidents事故原因事故原因Actions Inadequate行动不足行动不足Improper Cleaning 不适当的清洁不适当的清洁This is the assorted debris thatcan be collected on a filter duringblow through of a “clean” oxygenSystem 这是在对一个这是在对一个“清洁的清洁的”氧系统进行吹扫后，氧系统进行吹扫后，在过滤器收集到的各类碎片残渣。在过滤器收集到的各类碎片残渣。Dos and donts of oxygen safety 为保证氧气安全的“应做”和“不应做”DOsDONTs use approved materials tighten leaking joints under pressure use “oxygen cleaned” materials to the appropriatelevel of cleanliness use oil or grease to lubricate components