Single-line or Fast Loop Sampling System: Which to Choose and Why?

Sampling is one of the most crucial steps in the Oil and Gas industry since accurate sampling analysis leads to premium product quality. Sampling is performing testing on a small amount of product to ensure the overall product quality. Now, the accuracy of the results also depends on various factors like which sampling system you use, are you aware of basic security and safety checks, etc. 

So, without delaying any further, let us understand the two main types of sampling system - Single-line and fast loops, and also which system should you use for better results. 

In this type of sampling system, a sample gets transported to the analyzer location and then it continues to the final disposal point. Usually, this type of sampling system is used for gas samples. Also, if the gas samples are preconditioned, then there is a field station module is used along with a single-line system. 

This sampling system is better for small samples since all of them get directly transported to the final disposal point. If the sample volume is large, using a single-line sampling system might not be the best option. 

You may now be aware of the single-line sampling system. Let us now understand the other type - the fast loop sampling system. 

In a fast loop sampling system, the sample is transported to the analyzer location and from there, only a small amount of the sample gets through the analyzer. The rest returns to the tap. This type of sampling system is usually used for liquid samples. However, in rare cases, it may be used for gaseous samples as well. 

Using this type of sampling system could prove to be very beneficial since it allows only a small portion of the fluid to pass through the analyzer location. This means that the chances of getting improper or inaccurate results are reduced. 

Now, coming to the original question - which sampling system to use and why. Well, to understand this, let us first understand the difference between both types. 

The primary difference lies in the process itself. A single line transports the sample straight to the final disposal point while only a small amount of sample gets through the analyzer in fast-loop sampling. 

The other notable difference is that fast loop sampling may never need a field station module since liquid samples do not need preconditioning. The purposes of using both sampling systems are different. However, fast loop sampling is more accurate than single-line, let us see how. 

Here are a few reasons why fast loop sampling gives more accurate results than a single-line system:

Overall, a fast loop system is faster than a single-line system which makes it more efficient. Usually, it is used for valuable liquids or fluids that cannot be flared. 

Wrapping up 

Hopefully, you now know the two main types of sampling systems, their uses, differences, and which one to prefer when. Depending on your requirements and on the types of samples you want to perform sampling on, the decision of whether to go for single-line or fast-loop will differ.