Flow assurance specialists have long faced the challenge of maintaining continuous flow through subsea pipelines. Over time deposits can build-up and can lead to shortfall of revenue through lost production. When these issues occur, they face the problem of determining the exact location and nature of the blockage in order to take action, without risking damage to the subsea pipeline.
In this post we will explain step by step how to pinpoint the exact location of any flow assurance issues including how to investigate them further, determining whether they are hydrate deposits or wax deposits, or indeed distinguishing between asphaltene deposits or scale deposition. All without shutting down production or modifying subsea pipelines in any way.
1) Do you know the location of the flow assurance issues?
In some cases it is clear where the blockage or issue is. In others it could be multiple deposits across several kilometers of pipeline. Deciding if you are certain on the location of any deposits is the first step to addressing the issues.
Even if modelling indicates where issues are occurring, for the avoidance of doubt it might still be prudent to use a fast screening pipeline inspection technique. This will ensure all issues are known before deciding on next steps to remediate the line. Tracerco offer a fast screening service to locate flow assurance issues known as ExplorerTM. You can book a lunch and learn to find out more.
2) How much more do you need to know in order to effectively deal with the blocked subsea pipeline?
You might find after using the screening tool you have all the data you need to decide on your remedial action. In other cases, you may need to know more detail on what type of blockage you are faced with and the total amount prior to commencing a cleaning campaign.
The action you take to remove hydrate build-up will be very different to removal of scale deposition or wax. So it's important you're confident you have all the data to avoid taking any action that could be ineffectual, wasting time and therefore increasing lost production and consequently revenue and resource losses.
3) Determine the extent and nature of the blockage
If you decide you need to know more detail then you don't have a lot of options available to you. You can spend time modeling the pipeline using data from the screening activity, but this will not give you absolute confidence and certainty of what's causing the issues.
Tracerco offer a detailed scanning service through DiscoveryTM which can distinguish between wax, hydrate, asphaltene or scale deposition at density differences of 0.05g/cc. You can see for yourself the data DiscoveryTM can obtain by sending us your pipe samples for a live blind test.
4) Plan your remedial action
Once you understand the full extent and nature of the flow assurance issues within your line the questions to consider are:
- Can you remediate with a non-invasive procedure?
- Do you need to remediate using invasive procedures?
The latter has consequences for an infield line, as it would not be possible to bring it back online having undergone invasive procedures. This is why it's crucial to get a full understanding of the blockage and plan the corrective action carefully.
5) Confirm the success of any action taken
Once you have taken the action you may want to confirm the procedure was successful. Here you can use DiscoveryTM to scan the areas where you were experiencing issues. The technology will provide a detailed tomographic scan. You can book a lunch and learn to find out more.
If you follow these steps you should have all the information you need to be confident on how to deal with your flow assurance issues. Tracerco offer technologies to give you the data you need. Challenge us with your toughest flowline issue. You can send us your pipe and book a live blind test at one of our state of the art testing centres. See for yourself the unique data available.
