The production of gas and oil is often accompanied by water, either from the formation, from condensation, or from water injected as lift assist. Acid gases, such as hydrogen sulphide (H2S) and carbon dioxide (CO2) are often present in produced fluids, and oxygen is sometimes a contaminant in the water used for injection. These acid gases increase the corrosivity of the waters to steel, and can significantly impact the safe operating life of production tubulars and equipment, production vessels, and transportation systems.
The presence or absence of multiple phases (gas, water, and oil or condensate) in the same system can complicate the problem of controlling corrosion. Internal corrosion in a tubing string, vessel, or pipeline can have a significant impact on corrosivity and is influenced by conditions such as temperature, the flow regime or pattern of fluids, water wetting and composition and surface condition of the steel in a tubing string, vessel, or pipeline can have a significant impact on corrosivity.
The potential consequences of internal pipeline corrosion represent both safety and economic concerns to various sectors of the industry. Mitigating corrosion is critical as the initiation corrosion cells can negatively affect the integrity of the pipeline in service. Additionally, the build up of corrosion and bacterial by-products on the pipe walls can cause problems at later stages of a pipeline’s operation life including under-deposit corrosion and contamination of fluids passing through the pipe.
The pipeline costs are a considerable part of the investment in the petro chemical industry, and for long-distance, large-diameter pipelines, they can become prohibitively high if the corrosivity of the fluid necessitates the use of corrosion-resistant alloys instead of carbon steel. Better understanding and control of the corrosion of carbon steel can increase its application range and therefore have a large economic impact.
Corrosion occurs in various forms, such as pitting corrosion from water droplets, embrittlement from hydrogen, and stress corrosion cracking from sulphide attack. Corrosion is fought by a complex system of monitoring, preventative repairs and careful use of materials.
Corrosion Control in gas, oil and water course provides an overview of refinery process units and specific process descriptions, and focuses on the examination and identification of metallurgical problems that occurs in process units and methods of monitoring and damage reduction.
At the end of this course participants will have learned about:
Corrosion principles and mechanisms
Types of corrosion that are related to the oil, gas and water
Materials of Construction for Refinery Applications
Corrosion Monitoring and inspection Methods
Aspects of Corrosion inspection and anti corrosion management and mitigation
Introduction to Corrosion•General corrosion, Corrosion mechanisms, Types of corrosion, Causes of corrosion failures
Parameters influencing corrosion in the refining industry•Different hydro carbon streams, Sulphur, Acidity, (TAN) number, pH Control, Desalting, Distilling, High and Low temp corrosion
Types of Corrosion in the Refinery Industry, Related to Oil, Gas and Water