ICDA Case Study: 43 Year Old Sour Gas Pipeline

2006 ◽  
Author(s):  
Theo Abels ◽  
Nguyen Bich
Keyword(s):  
Primary Source ◽  
Guided Wave ◽  
Corrosion Monitoring ◽  
Processing Plant ◽  
Internal Corrosion ◽  
Gas Processing ◽  
Direct Assessment ◽  
Anomaly Detector ◽  
On Line ◽  
Sour Gas

A 42km/356mm diameter pipeline was built and commissioned in 1962 and is the primary source of sour gas to a sour gas processing plant. The pipeline has operated as a dehydrated sour gas/condensate pipeline, and was assessed as a candidate for an Internal Corrosion Direct Assessment (ICDA). This analysis came with the challenge of a lack of operational and inspection history. The decision was made to obtain as much history as possible by interviewing previous operators, and to perform an ICDA analysis based on this information. The ICDA analysis was performed by a technical specialist utilizing 1) wet sour gas corrosion methodology and 2) ICDA (critical angle) technology. The analysis was performed for one ICDA region. Nine assessment cases were identified as the operating criteria changed with time and each was assessed. On occasion the gas specifications had criteria below the minimum levels of influence, and analysis was also performed with these adjusted to force identification of potential internal corrosion locations. The results were presented identifying two locations of potential long-term corrosion, and one location susceptible to corrosion post 2000. Following a review of the ICDA analysis, it was felt that there was sufficient confidence to proceed with the direct assessments. The decision was taken to expose the three identified locations. The direct assessment at all three locations was performed using guided wave UT as the initial anomaly detector, and phased array UT was then utilized to confirm any anomalies, and was run along the bottom of the exposed line to confirm no anomalies were missed. The results of the NDE indicated no anomalies of more than 10%, and it was concluded that no significant internal corrosion of concern exists. The final phase of the ICDA (post assessment) concluded that the analysis was successful and that the ICDA project was a success. The re assessment intervals will be driven by any future changes in the transported product, and information obtained from on line corrosion monitoring.

The effect of sulfur dioxide upon the metabolic level of adenosine triphosphate

1979 ◽  
Vol 57 (7) ◽  
pp. 759-764 ◽  
Author(s):  
Geoffrey W. Harvey ◽  
Allan H. Legge
Keyword(s):  
Sulfur Dioxide ◽  
Pinus Contorta ◽  
Ambient Air ◽  
Field Studies ◽  
Growth Chamber ◽  
Processing Plant ◽  
Atp Content ◽  
Gas Processing ◽  
Sulfur Dioxide Concentration ◽  
Sour Gas

The ATP content of lodgepole – jack pine (Pinus contorta × banksiana) hybrids in the cordillerean–boreal transition zone was monitored during sulfur dioxide fumigations. Foliage was stabilized for analysis during the course of sulfur dioxide fumigations originating from a sour gas processing plant located in west-central Alberta. Controlled sulfur dioxide fumigations of seedlings were conducted in the laboratory to measure their effect upon ATP content. Field studies demonstrated that ATP concentrations of needle cells declined as sulfur dioxide concentration increased in the ambient air. An inverse linear relationship was found between ATP content and the measured sulfur dioxide concentration. The effect could be repeated in the laboratory with growth chamber cultured seedlings only in exceptional cases. It was repeated with detached branches from the field site exposed to sulfur dioxide under laboratory conditions. The results illustrate the fundamental differences between foliage preadapted to low-level sulfur dioxide fumigations and foliage grown under optimal conditions in a growth chamber.

Comparison of two atmospheric-dispersion models to assess farm-site exposure to sour-gas processing-plant emissions

2003 ◽  
Vol 57 (1-2) ◽  
pp. 15-34 ◽  
Author(s):  
H.Morgan Scott ◽  
Colin L Soskolne ◽  
S Wayne Martin ◽  
Erik A Ellehoj ◽  
Robert W Coppock ◽  
...  
Keyword(s):  
Atmospheric Dispersion ◽  
Processing Plant ◽  
Dispersion Models ◽  
Gas Processing ◽  
Atmospheric Dispersion Models ◽  
Plant Emissions ◽  
Sour Gas

scholarly journals On-Line Corrosion Monitoring of Plate Structures Based on Guided Wave Tomography Using Piezoelectric Sensors

Sensors ◽  
2017 ◽  
Vol 17 (12) ◽  
pp. 2882 ◽  
Author(s):  
Jing Rao ◽  
Madis Ratassepp ◽  
Danylo Lisevych ◽  
Mahadhir Hamzah Caffoor ◽  
Zheng Fan
Keyword(s):  
Guided Wave ◽  
Piezoelectric Sensors ◽  
Corrosion Monitoring ◽  
Plate Structures ◽  
On Line ◽  
Wave Tomography

Water treatment to reduce internal corrosion in the drinking water distribution system in Oslo

2001 ◽  
Vol 1 (3) ◽  
pp. 91-96 ◽  
Author(s):  
L.J. Hem ◽  
E.A. Vik ◽  
A. Bjørnson-Langen
Keyword(s):  
Water Treatment ◽  
Corrosion Rate ◽  
Distribution System ◽  
Water Distribution ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Corrosion Monitoring ◽  
Copper Corrosion ◽  
Iron Corrosion ◽  
Internal Corrosion

In 1995 the new Skullerud water treatment plant was put into operation. The new water treatment includes colour removal and corrosion control with an increase of pH, alkalinity and calcium concentration in addition to the old treatment, which included straining and chlorination only. Comparative measurements of internal corrosion were conducted before and after the installation of the new treatment plant. The effect of the new water treatment on the internal corrosion was approximately a 20% reduction in iron corrosion and a 70% reduction in copper corrosion. The heavy metals content in standing water was reduced by approximately 90%. A separate internal corrosion monitoring programme was conducted, studying the effects of other water qualities on the internal corrosion rate. Corrosion coupons were exposed to the different water qualities for nine months. The results showed that the best protection of iron was achieved with water supersaturated with calcium carbonate. Neither a high content of free carbon dioxide or the use of the corrosion inhibitor sodium silicate significantly reduced the iron corrosion rate compared to the present treated water quality. The copper corrosion rate was mainly related to the pH in the water.

Integrity Assessment of Non-Piggable Pipeline Through Direct Assessment

2013 ◽  
Author(s):  
Jai Prakash Sah ◽  
Mohammad Tanweer Akhter
Keyword(s):  
Hydrostatic Pressure ◽  
Natural Gas ◽  
Stress Corrosion ◽  
Health Assessment ◽  
Assessment Method ◽  
Pipeline System ◽  
Internal Corrosion ◽  
Integrity Assessment ◽  
Direct Assessment ◽  
External Corrosion

Managing the integrity of pipeline system is the primary goal of every pipeline operator. To ensure the integrity of pipeline system, its health assessment is very important and critical for ensuring safety of environment, human resources and its assets. In long term, managing pipeline integrity is an investment to asset protection which ultimately results in cost saving. Typically, the health assessment to managing the integrity of pipeline system is a function of operational experience and corporate philosophy. There is no single approach that can provide the best solution for all pipeline system. Only a comprehensive, systematic and integrated integrity management program provides the means to improve the safety of pipeline systems. Such programme provides the information for an operator to effectively allocate resources for appropriate prevention, detection and mitigation activities that will result in improved safety and a reduction in the number of incidents. Presently GAIL (INDIA) LTD. is operating & maintaining approximately 10,000Kms of natural gas/RLNG/LPG pipeline and HVJ Pipeline is the largest pipeline network of India which transports more than 50% of total gas being consumed in this country. HVJ pipeline system consists of more than 4500 Kms of pipeline having diameter range from 04” to 48”, which consist of piggable as well as non-piggable pipeline. Though, lengthwise non-piggable pipeline is very less but their importance cannot be ignored in to the totality because of their critical nature. Typically, pipeline with small length & connected to dispatch terminal are non-piggable and these pipelines are used to feed the gas to the consumer. Today pipeline industries are having three different types of inspection techniques available for inspection of the pipeline. 1. Inline inspection 2. Hydrostatic pressure testing 3. Direct assessment (DA) Inline inspection is possible only for piggable pipeline i.e. pipeline with facilities of pig launching & receiving and hydrostatic pressure testing is not possible for the pipeline under continuous operation. Thus we are left with direct assessment method to assess health of the non-piggable pipelines. Basically, direct assessment is a structured multi-step evaluation method to examine and identify the potential problem areas relating to internal corrosion, external corrosion, and stress corrosion cracking using ICDA (Internal Corrosion Direct Assessment), ECDA (External Corrosion Direct Assessment) and SCCDA (Stress Corrosion Direct Assessment). All the above DA is four steps iterative method & consist of following steps; a. Pre assessment b. Indirect assessment c. Direct assessment d. Post assessment Considering the importance of non-piggable pipeline, integrity assessment of following non piggable pipeline has done through direct assessment method. 1. 30 inch dia pipeline of length 0.6 km and handling 18.4 MMSCMD of natural gas 2. 18 inch dia pipeline of length 3.65 km and handling 4.0 MMSCMD of natural gas 3. 12 inch dia pipeline of length 2.08 km and handling 3.4 MMSCMD of natural gas In addition to ICDA, ECDA & SCCDA, Long Range Ultrasonic Thickness (LRUT-a guided wave technology) has also been carried out to detect the metal loss at excavated locations observed by ICDA & ECDA. Direct assessment survey for above pipelines has been conducted and based on the survey; high consequence areas have been identified. All the high consequence area has been excavated and inspected. No appreciable corrosion and thickness loss have observed at any area. However, pipeline segments have been identified which are most vulnerable and may have corrosion in future.

Internal Corrosion Direct Assessment for Pipelines Carrying Wet Gas - Methodology

2004 ◽  
Author(s):  
Oliver Moghissi ◽  
Deanna Burwell ◽  
Rick Eckert ◽  
Jose Vera ◽  
Narasi Sridhar ◽  
...  
Keyword(s):  
Corrosion Rate ◽  
Flow Regimes ◽  
Distribution Model ◽  
Liquid Volume ◽  
Internal Corrosion ◽  
Integrity Verification ◽  
Direct Assessment ◽  
Wet Gas ◽  
Pipeline Segment ◽  
Flow Effects

An Internal Corrosion Direct Assessment methodology is proposed for wet gas pipelines (WG-ICDA). Wet gas systems (i.e., those normally containing liquids) include storage and gathering systems with large gas-to-liquid volume ratios. Wet gas systems are not well represented by ICDA for normally dry gas, and existing corrosion models applied to wet gas systems are not sufficiently targeted at integrity verification. The essential focus of WG-ICDA compared to other internal corrosion models is the discrimination of conditions along the length of a pipeline so that possible local integrity threats with respect to internal corrosion are identified and mitigated. The basis of WG-ICDA is to prioritize locations along a pipeline segment by factors of traditional corrosion rate, flow effects, and other influencing factors. Corrosion rate depends on gas quality, liquid chemistry, pressure, and temperature. The corrosion rate can be normalized because WG-ICDA as integrity verification only concerns itself with corrosion distribution (i.e., the location along a pipeline segment where corrosion is more severe than other locations). Flow effects include possible flow regimes and the presence of water from condensation (at locations of heat loss). Expected possible flow regimes are stratified, slugging, and annular. The final term captures other factors influencing corrosion rate distribution. These factors include corrosion inhibition (batch and continuous, solubility and dispersibility in hydrocarbon and aqueous phases), biocide treatments, hydrocarbon condensates (including emulsion characteristics), maintenance pigging, bacteria, solids/scale, and other products. WG-ICDA follows the same four-step process as all other Direct Assessment (DA) methods: 1) Pre-Assessment: Data is collected, a feasibility analysis is performed, and the pipeline segment is divided into regions. 2) Indirect Inspections: Measurements are taken or calculations are performed to prioritize locations along a particular pipeline segment for susceptibility to corrosion. For WG-ICDA, the factors contributing to the distribution of corrosion will be included and an initial assumption about corrosion distribution will be made. WG-ICDA is sufficiently flexible to allow the use of existing wet gas models within the framework of the overall process. 3) Direct (or Detailed) Examinations: The pipe is excavated and examined at locations prioritized to have the highest likelihood of corrosion. The examination must have sufficient detail to determine the existence, extent, and severity of corrosion. Examination of the internal surface of a pipe can involve non-destructive examination methods sufficient to identify and characterize internal defects. 4) Post-Assessment: Analysis of the indirect and direct examination data is performed to determine overall pipeline integrity, prioritize repairs, and set the interval for the next assessment. If the results of excavations do not match the original assumption, the corrosion distribution model will be updated to guide the next excavations (i.e., the operator returns to step 2).

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