What is the best way to design a corrosion-resistant pipeline system?

Regarding to market for material, I would like add that In some cases, technical factors may outweigh market factors. For example, if a piping system is required to transport a highly corrosive fluid, the material selection may be limited to a few highly resistant materials, regardless of cost. However, in other cases, market factors may outweigh technical factors. For example, if a piping system is required to transport a non-corrosive fluid, the material selection may be based on cost, availability, or other market factors. Ultimately, the decision of which material to use for piping and equipment is a complex one that must take into account both technical and market factors.

In crafting a corrosion-resistant pipeline system, the crux lies in selecting materials with precision. Technical nuances come into play, considering parameters like fluid type, concentration, temperature, pressure, and flow rate. Real-world data showcases the effectiveness of materials like stainless steel, known for its resistance to corrosion in aggressive environments. Carbon steel, though widely used, may demand protective coatings in specific scenarios, underlining the importance of understanding corrosion mechanisms. The choice between materials, be it nickel alloys or non-metallic options like composites, hinges on a meticulous alignment with service conditions for optimal pipeline resilience.

One of the first issues to be considered in selection a proper material for a pipeline is to know everything about the process service, including the type of fluid, the corrosive constituents, the possibility of solid particles in the fluid, the fluid regime in terms of being laminar or turbulent and the fluid speed. The responsible material engineer should gather all of the above mentioned information before commencing the material selection activity. The next important issue in selection of the proper material choice is to be fully aware of the market availabilities for different material choices. For example, in some countries non-metallic materials are available and economical choices while in some other places they’re not available.

Thank you Mohsen for your great point, but even regarding the corrosive service we need to first assess the local market because normally even for corrosive services there will be several choices and as a material engineer we need to first consider all choices and if possible it is necessary to consider the one which is more available in the local market. Of course. in some specific cases there would be only one choice.

It has two part to prevent and maintenance; the first one is, before disgning and commissioning so should to select a proper material to make, include type of matrial, climate condition, kind of soil, what fluid will pass through the pipeline, what’s the fluid flow regime, etc… And the second one is; after assembling so contains: use of some chemicals due to the fluid such as anti scalant, demulsifiers, anti foams, corrosion inhibitors, oxygen scavengers,etc… and some of the other protecting process such as installing the Anode, using the coupans, use of the best painting color due to the type of pipeline.

It is important to bear in mind that corrosion protection measures have to be considered at the same time as the material selection is being done. In another word, the selection of the corrosion protection measure is a part of the material selection procedure. For example, when CS is being considered as a choice for a buried pipeline, the overall price of protective coating and cathodic protection need to be considered as a measure for considering CS as a choice. In some cases, for example, considering nonmetallic choices which does not need external coating and cathodic protection might be considered as the best economical choice.

Coatings: These act as resilient barriers, exemplified by epoxy coatings excelling in harsh chemical environments. Cathodic Protection: External electric currents fortify the pipeline, proven effective in safeguarding buried pipes from corrosion in aggressive soils. Inhibitors: Chemical warriors, inhibitors like corrosion inhibitors modify corrosive reactions, mitigating degradation in practice. Biocides: Serving as a shield against microbial threats, biocides curb microorganism-induced corrosion.

Corrosion monitoring is an issue which may not be taken seriously during the design stage and sometimes during the operational phase owners might face with some difficulties and sometimes they need to consider the installation of some corrosion monitoring measures. Of course, in many cases they didn't understand such necessity and suddenly face with destructive failures. So, the necessity of suitable corrosion monitoring measures has to be considered by design engineering firms.

Always consider inspect ability. In many cases pipelines have been constructed in a way that makes a pig run impossible or extremely difficult, which will ultimately lead to problems later in the pipeline's life when it becomes necessary to assure pipeline integrity.

Direct Methods: Delving into the heart of the pipeline, direct methods inspect and test the material itself. Techniques like using coupons, probes, sensors, or pigging devices offer real-time insights into the material's condition. Indirect Methods: A subtler approach involves monitoring fluid or gas properties. Measuring parameters such as pH, conductivity, oxygen content, or corrosion products unveils potential corrosion threats and aids in evaluating the effectiveness of material selection and corrosion protection measures.

Setting Objectives: The program aimed to reduce corrosion-related incidents by 20% within a year. Roles and Responsibilities: Engineers were assigned to regularly inspect corrosion-prone sections, ensuring proactive maintenance. Data Collection and Analysis: Utilizing corrosion coupons and sensors, the team collected real-time data on corrosion rates, enabling informed decision-making. Action Implementation: In response to increasing corrosion rates in specific segments, targeted coating enhancements were executed. Results Evaluation: After implementation, corrosion-related incidents decreased by 25%, surpassing the initially set objective.

Empirical Models: Drawing strength from experimental data and statistical correlations, empirical models offer a practical understanding of corrosion behavior derived from real-world scenarios. Mechanistic Models: Rooted in physical and chemical principles, mechanistic models delve deep into the underlying mechanisms and factors governing corrosion, providing a nuanced comprehension of the processes at play. Numerical Models: Leveraging computational methods and algorithms, numerical models simulate and predict corrosion behavior, offering a quantitative and precise analysis for decision-making and risk assessment.

This should be the second step, taken immediately after the project requirements have been agreed. The corrosion model will be the primary tool for selecting materials and corrosion management strategies.

This is really important. Several pipeline failures have occurred because the operators did not understand corrosion or the importance of corrosion management. A typical problem is switching off chemical treatment to save money.

Sustainability and minimising environmental impact are no longer afterthoughts. Green legislation is already limiting chemical treatments and there is lightly to be greater pressure to demonstrate that your material and construction selection is "sustainable" in future.