Cathodic Protection Technology hauv Onshore Roj Thiab Gas Fields

Cathodic tiv thaiv thev naus laus zis tseem yog qhov tseem ceeb hauv kev siv roj av thiab roj av, feem ntau yog siv los tiv thaiv corrosion ntawm cov chaw hlau los ntawm cov av, dej hauv av, thiab kev thauj mus los.

1. Cov kav dej faus

• Flowlines
• Cov kav xa dej
• Cov kav dej / roj txhaj tshuaj

2. Cia Tank

• Sab nrauv thiab sab hauv qab daim hlau ntawm cov roj crude cia tanks
• Tsim cov dej kho tank

3. Qhov chaw zoo

• Cov phab ntsa sab nrauv
• Cov khoom siv Wellhead

4. Cov khoom siv hauv chaw nres tsheb

• Av -hu rau cov qauv kev txhawb nqa hauv qab ntawm cov khoom sib cais thiab cov khoom siv hluav taws xob sib txuas
• Grounding systems

1. Txoj kev Sacrificial Anode

Application Scenario:

• luv- cov kav dej nyob deb lossis cov tank me me.
• Tej thaj chaw deb qhov chaw zoo uas tsis muaj hluav taws xob ruaj khov.

Common Anode Khoom:

• Magnesium alloy (Mg): High tsav voltage, haum rau siab -resistivity av.
• Zinc alloy (Zn): Tsawg tsav hluav taws xob, haum rau qis- cov av tsis kam.

Installation Methods:

• Pipelines: Sacrificial anodes ntsia rau ntawm ob sab.
• Cia tso tsheb hlau luam: Anodes teem rau hauv kab sib chaws los yog lub nplhaib, sib npaug sib npaug hauv qab lub tank hauv qab.

2. Txaus siab rau txoj kev tam sim no

Siv tau Scenarios:

• Transmission pipelines los yog chaw nres tsheb faus pipelines.
• Loj cia tank hauv qab phaj undersurface.

Cov ntsiab lus tseem ceeb:

1) Pab anodes:

• High -silicon cam khwb cia hlau anode (HSCI): Acid-tiv taus av sib xws, 20-30-xyoo kev pab cuam lub neej.
• MMO anode: Lub zog siab, lub teeb yuag, siab - ntsuas cov zis tam sim no, 25 ~ 40-xyoo kev pab cuam lub neej.

2) Transformer rectifier: Ntau hom kev ua haujlwm (qhov muaj peev xwm tsis tu ncua / tam sim no / voltage).

3) Anode av txaj:

• Pem hauv ntej faus hauv av txaj: kev tsim kho yooj yim, hneev taw loj.
• Kev sib sib zog nqus hauv av txaj: Tsawg grounding kuj, compact hneev taw.

1. Kev tiv thaiv cov kav dej faus

Kev kho mob anodes:

• Mg alloy anodes rau cov suab puam / siab- thaj chaw tiv thaiv (xws li Xinjiang Oilfield).
• Zn alloy anodes rau cov av nplaum ib puag ncig (xws li Sichuan Gas Field).

Txaus siab tam sim no:

• Kev faib cov txaj hauv av + ntse rectifiers (piv txwv li, West-East Gas Pipeline).
• CIPS (Kaum Lub Sijhawm Muaj Peev Xwm Kev Tshawb Fawb) rau kev kuaj xyuas kev tiv thaiv ib ntus.

2. Kev tiv thaiv lub tank

Tank hauv qab phaj sab nrauv:

• Sacrificial anode: Mg / Zn anodes nyob rau hauv daim phiaj / nplhaib layouts rau niaj hnub faib.
• Txaus siab tam sim no: MMO mesh anodes, hloov tau anodes (piv txwv li, 100,000 m³ crude tso tsheb hlau luam).

Kev tiv thaiv sab hauv:

• Cov dej tso tsheb hlau luam: Suspended Al alloy anodes (piv txwv li, Al-Zn-In) hauv cov kua tank.

3. Kev Tiv Thaiv Qhov Chaw Zoo

Casing sab nrauv:

• Zn anodes ncaj qha welded rau casing qis seem (piv txwv li, shale gas qhov dej).
• Casing grounding cells" los tiv thaiv kev cuam tshuam tam sim no.

Cov khoom siv Wellhead:

• Ua ke txheej + Mg anode tiv thaiv.

4. Chaw nres tsheb cov cuab yeej tiv thaiv

Separator/heat exchanger foundations:

• Mg anode blocks ua ntej-embedded nyob rau hauv lub hauv paus pob zeb.

Grounding systems:

• Zn-coated steel los yog Zn anode grounding electrodes.

1. High H₂S Ib puag ncig

Qhov teeb meem:

• H₂S accelerates localized corrosion (xws li sulfide stress cracking).

Kev daws:

• Ua kom muaj peev xwm tiv thaiv rau -0.85 ~ 0.95V (vs. CSE).
• Siv sulfur-cov ntaub ntawv tiv thaiv anode (piv txwv li, tshwj xeeb Al alloys).

2. Kev cuam tshuam tam sim no

Qhov chaw:

• Nyob ib sab siab -voltage kis tau tus mob, electrified railways, lwm yam CP systems.

Kev daws:

• Kev tsis ncaj ncees tam sim no cov kev tshawb fawb txhawm rau txheeb xyuas thaj chaw cuam tshuam / qhov chaw.
• Txhim kho cov pa tawm tam sim no.

3. Frozen av cheeb tsam Corrosion

Qhov teeb meem:

• Cov av khov-thaw cycles ua rau cov txheej txheem tsis sib xws thiab kev hloov pauv raws caij nyoog.

Kev daws:

• Sib sib zog nqus anode hauv av txaj.
• Tsawg-kub tau tshaj anodes (piv txwv li, siab -purity Mg).

4. Microbial Corrosion (MIC)

Qhov teeb meem:

• Sulfate-txo cov kab mob (SRB) kev loj hlob hauv cov av anaerobic.

Kev daws:

• Ua ke biocides + cathodic tiv thaiv.
• Ua kom muaj peev xwm qis dua -0.95V (inhibits SRB kev ua haujlwm).

1. Muaj peev xwm saib xyuas:

• Portable CSE reference electrodes: Cov kav dej tsis tu ncua / tank peev xwm ntsuas.
• Polarization probes + ntse chaw nres tsheb: tiag -lub sij hawm tiv thaiv tej zaum/stray tam sim no xyuas.

2. Kev soj ntsuam ntse:

• Tej thaj chaw deb rectifier cov ntaub ntawv kis tau tus mob ntawm wired/wireless/fiber/mobile networks.
• Kev tshuaj xyuas Drone rau cov chaw kuaj mob (muaj feem xyuam rau cov kav xa dej).

3. Kev tu lub voj voog:

• Sacrificial anode seem raug kuaj xyuas txhua 5 xyoos.
• Txaus siab rau cov tshuab tam sim no: Rectifiers / av txaj tiv thaiv tau tshuaj xyuas ib nrab-ib xyoos.

1. International:

• TS EN ISO 15589-1: Petroleum, petrochemical thiab natural gas industries - Cathodic kev tiv thaiv ntawm cov kav xa dej - Ntu 1: Cov kav dej hauv av.
• NACE SP0169-2024: Kev tswj ntawm Sab Nraud Corrosion nyob rau hauv av los yog Submerged Metallic Piping Systems.

2. Teb chaws (Tuam Tshoj):

• GB/T 21448-2017: Cathodic Protection Technical Standard for buried Steel Pipelines.
• SY/T 5919-2009: Technical Management Code for Cathodic Protection of Buried Steel Pipelines.

• Iraq Block 9 Crude Roj & Gas Central Processing Facility.
• Rumaila Oilfield BASE SCOPE Q3/Q4 2023 CP Cov ntaub ntawv.
• Majnoon Oilfield External Pipeline Temporary CP System.
• Daqing Oilfield Gulong Shale Roj Project.
• Tarim Oilfield (Xinjiang) Bozi-Dabei Gas Field.
• CNPC Southern Sichuan Shale Gas Field.

Rau onshore roj/gas teb, cathodic tiv thaiv yuav tsum tau hloov tau raws li cov yam ntxwv ntawm av, media corrosivity, thiab hom chaw:

• Sacrificial anodes: Haum rau me me - nplai, qis- daim ntawv thov kev tu.
• Txaus siab rau tam sim no: Qhov zoo tshaj plaws rau qhov ntev - deb / complex ib puag ncig nrog kev tswj tau siab.
• Kev tiv thaiv sib xyaw ua ke: feem ntau ua ke nrog 3PE txheej thiab inhibitors rau ntau- thaiv kev tiv thaiv.
• Los ntawm kev xaiv thev naus laus zis thiab kev saib xyuas ntse (xws li kev hloov kho tej thaj chaw deb), kev pheej hmoo corrosion tuaj yeem txo qis, ua kom muaj kev nyab xeeb tshaj li 30 xyoo.