corrosion oil
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•1 Dipartimento CMIC Giulio Natta POLITECNICO DI MILANO Dipartimento di Chimica, Materiali e Ingegneria Chimica “Giulio Natta” Politecnico di Milano Corrosion and corrosion control in oil and gas industry Forms Forms of corrosion of corrosion Dipartimento CMIC Giulio Natta POLITECNICO DI MILANO
description
corrosion control in oil and gas
Transcript of corrosion oil
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DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Dipartimento di Chimica, Materiali e Ingegneria ChimicaGiulio Natta
Politecnico di Milano
Corrosion and corrosion control in oil and gas industry
FormsForms of corrosionof corrosion
DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
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DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Material with an active behaviourUniform attack metal thickness
reductionThe more common form of corrosion, and perhaps the less dangerous (it is predictable)
Generalised corrosion
DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Material with an activepassive behaviour
Localised breakdown of passive filmCauses chemical PITTING - CREVICE
metallurgic INTERGRANULAR
mechanic TURBOLENCEEROSIONCAVITATION
strenght SCC - FATIQUE - HYDROGEN
Localised corrosion
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DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
active-passive material
presence of chlorides
presence of oxydant species
Pitting corrosion
DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Pitting corrosion
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DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Pitting corrosion
DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Pitting corrosion
H 2O
Cl-
H +
Fe+ +
A cciaio
Film dipassivit
C l-
e-
H 2O , O 2 O H -
Zona attiva (pit)pH < 5
.
Passive film
MetalActive areapH < 5
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DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Pitting potential (Epit)
E pit
Chlorides effect
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Giulio Natta
POLITECNICO DI MILANO
E pit
Ecorr, 2 > E pit
2YEScorr
1
Ecorr, 1 < E pit NO corr
Pitting corrosion
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DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Chlorides Temp. pH
Chlorideseffect
Influence of environment
Pitting potential (Epit)
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Giulio Natta
POLITECNICO DI MILANO
Influence of the material
304316
Pitting potential (Epit)
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E corr > E pit
CorrosionCorrosion PotentialPotentialoxygen contentpresence of other oxydantspresence of bacteria
Initiation of pitting corrosion
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Giulio Natta
POLITECNICO DI MILANO
PREN = %Cr + 3,3 %Mo + 16 %N
AISI 304 18AISI 316 24-26Leghe 20 27-32Incoloy 825 33super-austenitic > 40
Pitting Resistance Equivalent Number
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Giulio Natta
POLITECNICO DI MILANO
Propagation of pitting corrosion
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Giulio Natta
POLITECNICO DI MILANO
Propagation of pitting corrosion
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1. Remove chlorides and oxidizers, such as dissolved oxygen, from the environment
2. Employ proper material selection, alloying and heat treatment
3. Avoid stagnant (no flow) conditions, which help the development of aggressive conditions inside the pits
4. Use proper design for drainage
5. Use additives (inhibitors: the ones with SO42 and especially NO3 are known to reduce pitting
6. Use anodic or cathodic protection
7. Use proper surface treatment
Prevention of pitting corrosion
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Stainless steel - welding
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Crevice Corrosion
crackso-ringscalesdeadlock
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Crevice Corrosion
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POLITECNICO DI MILANO
Crevice Corrosion
DipartimentoCMIC
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POLITECNICO DI MILANO
Crevice Corrosion
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POLITECNICO DI MILANO
Crevice Corrosion
DipartimentoCMIC
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POLITECNICO DI MILANO
Crevice Corrosion
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POLITECNICO DI MILANO
Crevice Corrosion
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POLITECNICO DI MILANO
Intergranular Corrosion
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POLITECNICO DI MILANO
Intergranular Corrosion
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POLITECNICO DI MILANO
Erosion Corrosion
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Erosion Corrosion
DipartimentoCMIC
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POLITECNICO DI MILANO
Erosion Corrosion
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DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Erosion Corrosion
DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Erosion Corrosion
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DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Erosion Corrosion
DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Erosion Corrosion
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DipartimentoCMIC
Giulio Natta
POLITECNICO DI MILANO
Cavitation Corrosion
![Corrosion in Upstream Oil and Gas Industry[1]](https://static.fdocuments.net/doc/165x107/54654b50b4af9f583f8b4ec3/corrosion-in-upstream-oil-and-gas-industry1.jpg)
![Electrochemical Analysis of H S Corrosion on 13% Chromium … · S corrosion in the oil industry [3][4]. Another corrosion concern in the industry is the transportation of the oil](https://static.fdocuments.net/doc/165x107/5e858c8c0326e42d6147988b/electrochemical-analysis-of-h-s-corrosion-on-13-chromium-s-corrosion-in-the-oil.jpg)
