Warsaw University of Technology Faculty of Materials Science and Engineering Woloska 141, Warsaw, Poland

Transcription

1 Warsaw University of Technology Faculty of Materials Science and Engineering Woloska 141, Warsaw, Poland Michał Gloc*, Krystyna Lublińska, Krzysztof Rożniatowski, Krzysztof Jan Kurzydłowski THE INFLUENCE OF BIOGAS ON DEGRADATION OF TRANSFER PIPELINES 1 / 31

2 OUTLINE 1. Introduction 2. Research goals 3. Investigated materials and research techniques 4. Results 5. Conclusions 2 / 31

3 Faculty of Materials Science and Engineering Brief informations Warsaw 3 / 31

4 Faculty of Materials Science and Engineering Research domains 1. nanomaterials and nanotechnologies (NANO) 2. biomaterials and bioengineering (BIO) 3. functional and tailored materials (FUNCTION) 4. materials for energy (ENERGY) 5. surface engineering (SURFACE) 6. degradation of engineering materials (DEGRADATION) 7. modern methods of materials characterisation (CHARACTERISATION) 8. multiscale modelling (MODELLING) 4 / 31

5 Faculty of Materials Science and Engineering Research activities - NANO fabrication methods of nanomaterials; high strength nanostructured metallic materials, polymers modified with nanoparticles magnetic nanoparticles and nanomaterials sintering of nanocrystalline composites using the impulse plasma method 5 / 31

6 Faculty of Materials Science and Engineering Research activities - BIO fabrication of scaffolds for tissue engineering nanostructured titanium for implants design and development of shoulder prosthesis development of new ceramic-polymer composites for dental applications Porous Ti scaffold coated with Ca/P 6 / 31

7 Faculty of Materials Science and Engineering Research activities - FUNCTION multilayered and particulate ceramic-metal composites smart materials (magnetoreological elastomers, magnetic shape memory alloys) materials for extreme environments intermetallics hard and soft magnetic materials 7 / 31

8 Faculty of Materials Science and Engineering Research activities - ENERGY Materials for fusion reactors Photovoltaics Energy storage Materials for geothermal energy sources Fuel cells Eurofer 97 steel for fusion reactors ITER 8 / 31

9 Faculty of Materials Science and Engineering Research activities - SURFACE glow discharge nitriding, carbonitriding, oxicarbonitriding, oxidizing processes of steels (also austenitic steels), titanium and its alloys hybrid methods for producing composite and multicomponent layers which combine glow discharge treatment with PVD nethods, chemical and electrochemical processes PVD techniques, in particular the impulse plasma deposition method chemical electroless and electrochemical methods for fabrication of composite and multicomponent coatings PACVD method with the use of metalorganic vapours in the gaseous atmosphere modifying the properties of metallic biomaterials (titanium and its alloys, austenitic stainless steels) using the newest surface engineering methods heat treatment of metals and alloys in vacuum and various protective atmospheres 9 / 31

10 Faculty of Materials Science and Engineering Research activities - DEGRADATION non destructive testing hydrogen degradation in-service monitoring of materials degradation processes H25N20S2 10µm 304L Non-destructive testing methods 10 / 31

11 Faculty of Materials Science and Engineering Research activities - CHARACTERISATION Electron microscopy: SEM, TEM, STEM Atomic Force Microscopy (AFM) Auger electron and photoelectron spectroscopy (AES, XPS) X-ray diffraction Stereology and image analysis 11 / 31

12 Faculty of Materials Science and Engineering Research activities - research infrastructure Structure HR STEM Hitachi HD2700 HR TEM Jeol JEM3010 (+ 2 x TEM) HR SEM Hitachi S5500 (+ 3 x SEM) X-ray diffractometer Bruker D8 Discover Series 2 SCANNING AUGER MICROPROBE MICROLAB 350, VG Scientific AFM Nanoscope Multimode IIIA FT-IR spectrometer Nicolet 6700 Properties DSC, DMA, DTA, TDA devices Impact hammer RESIL5,5 HYSITRON TriboScratch Dynamic testing machines MTS 810 and 858 Static testing machine QTest 10 and Zwick Ares Rheology System - TA Instrument Brookfield DV-II+ PRO Digital Viscometer Specimens preparation FIB Hitachi 2100 The ion polishing system 691 PIPS Model 656 Dimple Grinder The ion beam thinning unit IV3 F/L Double jet polisher Tenupol Ultrasonic disc cutter NDT Acoustic emission system Vallen AMSY-5 Ultrasonic flow detector Krautkramer USN 60 Phase Array Eddy current detector IZ 27 SI 12 / 31

13 RESEARCH GOALS The aim of this investigation was to determine the influence of biogas rich in hydrogen on microstructure of steels used in natural gas pipelines BIOGAS structural steels hydrogen degradation (hydrogen corrosion) microstructural changes reduction of useful properties 13 / 31

14 INVESTIGATED MATERIALS The materials used in this study were: Carbon steels marked as R35; L485; 09G2S Low alloy steel 13CrMO4-5 Those steels are generally used in gas infrastructures The R35 steel was exploited in natural gas pipeline for 10 years The chemical compositions (weight %) of researched steels are given in table Steel C Mn Si P S Cu Mo Cr R 35 0,7-0,16 0,4-0,75 0,12-0,75 max. 0,04 max. 0,04 0, L 485 0,12 1,66 0,36 0,007 0,0017 0, G2S 0,06 1,27 0,5 0,02 0,002 0,06 0,09 0,05 13CrMo4-5 0,8-0,18 0,5 0,35 0,030 max.0,025 0,3 0,6 1 Chemical composition of the studied materials [wt %] 14 / 31

15 RESEARCH TECHNIQUES Hydrogen charging Sample Light microscopy LM Scanning electron microscopy SEM Microhardness measurements Microscopy observations and microhardness measurements were applied for specimens before and after treatment in cathodic hydrogen charging 15 / 31

16 EXPERIMENTAL HYDROGEN CHARGING Hydrogen charging parameters: 0,5M H 2 SO 4 solution, with 1mg/dm 3 As 2 O 3 addition (hydrogen entry promoter), _ + ambient temperature, current density: 50mA/cm 2 time: from 2 to 60 minutes + power supply (i const.) _ specimen platinium anode H 2 SO 4 + As 2 O 3 16 / 31

17 RESULTS MICROSCOPY OBSERVATIONS R35 R35 Surface and microstructure of carbon steel R 35 and L 485 before hydrogen charging. To reveal the microstructure features the samples were chemically etched in mixture of nitric acid + ethanol. L485 L / 31

18 RESULTS MICROSCOPY OBSERVATIONS EFFECT OF HYDROGEN CHARGING - SURFACE OF R35 CARBON STEEL (exploited in natural gas pipeline for 10 years) LM SEM Blister with Microcraks Blisters with microcracks observed on the surface of the specimens after hydrogen charging (1h, 50mA/cm 2 ) 18 / 31

19 MICROSCOPY OBSERVATIONS EFFECT OF HYDROGEN CHARGING - SURFACE OF R35 CARBON STEEL (exploited in natural gas pipeline for 10 years) LM Microcraks SEM Blisters on the surface Blisters with microcracks on the surface of the specimens after hydrogen charging (1h, 50mA/cm 2 ) 19 / 31

20 MICROSCOPY OBSERVATIONS EFFECT OF HYDROGEN CHARGING - SURFACE OF L 485 CARBON STEEL LM LM Blisters with microcracks on the surface of the specimens after hydrogen charging (1h, 50mA/cm 2 ) 20 / 31

21 MICROSCOPY OBSERVATIONS EFFECT OF HYDROGEN CHARGING - SURFACE OF L 485 CARBON STEEL LM LM Blisters with microcracks on the surface of the specimens after hydrogen charging (1h, 50mA/cm 2 ) 21 / 31

22 MICROSCOPY OBSERVATIONS EFFECT OF HYDROGEN CHARGING - SURFACE OF 13CrMo4-5 LOW ALLOY STEEL LM LM Blisters with microcracks on the surface of the specimens after hydrogen charging (1h, 50mA/cm 2 ) 22 / 31

23 MICROSCOPY OBSERVATIONS EFFECT OF HYDROGEN CHARGING - SURFACE OF 3CrMo4-5 LOW ALLOY STEEL In contact with hydrogen surface LM LM Crack Crack Microcracks and crevices at deeper layers of the specimens 23 / 31

24 MICROSCOPY OBSERVATIONS EFFECT OF HYDROGEN CHARGING - SURFACE OF 09G2S CARBON STEEL SEM SEM in contact with hydrogen surface SEM images of cracks under hydrogen-induced blisters on the hydrogen charged surface of 09G2S carbon steel [1] [1]. M. Szwed, K. Lublińska, M. Wielgat, A. Zagórski, W. Spychalski, K. J. Kurzydłowski, Evaluation of hydrogen degradation by in-situ ultrasonic testing, Advances in Materials Science, 2011, in print 24 / 31

25 MICROSCOPY OBSERVATIONS EFFECT OF HYDROGEN CHARGING - SURFACE OF L485 AND R35 CARBON STEEL L 485, 2 min charged R 35, 2 min charged SEM SEM L 485, 10 min charged R 35, 10 min charged SEM SEM The surface of the specimens after hydrogen charging (2min, 10 min, 50mA/cm 2 ) 25 / 31

26 MICROHARDNESS MEASURMENTS 165 HV0, Base H 2min R35 Microhardness H 10min H 1h Microhardness were carried out with Vickers indenter applying a load of 50g for uncharged and hydrogen charged samples L 485 in 2, 10,60 min / 31

27 MICROHARDNESS MEASURMENTS 220 HV0, Base H 2min H 10min H 1h L485 Microhardness Microhardness were carried out with Vickers indenter applying a load of 50g for uncharged and hydrogen charged samples L 485 in 2, 10,60 min / 31

28 MICROHARDNESS MEASURMENTS z % L485, H - 1h R35, H - 1h L 485, H - 10min R 35, H - 10min Z %- relative increase of microhardnes calculated up to the pattern Z = (HVh-HVn) 100%/HVh, where: HVh - average microhardness for hydrogen charged sample HVn average microhardness for uncharged sample 28 / 31

29 CONCLUSIONS Gases (biogas), which contain hydrogen, can cause the deterioration of the mechanical properties of structural materials for pipelines. Hydrogen degrades the microstructure of carbon and low alloy steels used as materials in pipelines. Surface hydrogen-induced microcracks, crevices and blisters with microcracks can be observed by LM and SEM. Hydrogen corrosive damage (crevices) can be found in deeper layers of these steels. The microhardness for specimens after hydrogen charging is higher than before the hydrogen treatment. This is in agreement with changes in the microstructure. Microcarcks which are caused by the penetration of hydrogen through steels, can develop during the exploitation of pipelines. As a consequence, under variable stresses and the aggressive environment a critical crack may occur. This can be a potential reason for a pipeline breakdown 29 / 31

30 PLANS FOR FUTURE Developing current work Expand it in detailed research like TEM, STEM observations after short hydrogen expositions Determination of influence other biogas components on steels behaviour Expose steel samples in special containers contain pure hydrogen, biogas, methan and mixture of this gases - static conditions Expose steel samples in working pipelines - dynamic conditions consider flow and pressure 30 / 31

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