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Production Process Insights

Ensure Safety and Accuracy with Low-E Sampling Systems

Posted by Horacio Salinas, Jr. on 5/4/20 8:00 AM
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Selecting a Low-E Sampler

Petrochemical and refinery plants can eliminate sample imprecision by transitioning to a low-emission (low-e) closed loop sampling system. But choosing from the many types of low-e systems can be overwhelming. These guidelines will help you select the right low-e system for your process to establish a successful sampling program that will ensure operator safety and sample accuracy.

In the petrochemical and refinery industries, it’s critical that operations run safely and efficiently with controlled, real-time data. Plants can eliminate data imprecision by transitioning to a low-emission (low-e) closed loop gas and liquid sampling system. These systems are simple, safe and accurate ways to manage representative sampling in your plant.

Why low-e closed loop systems?

Closed loop systems keep liquids and gases (like poisonous hydrogen sulfide) contained and produce a sample through a series of valves and vents. This containment keeps plants compliant with stringent OSHA and EPA requirements that are the benchmarks of worker and environmental safety. Further, they eliminate VOC emissions and keep the sample volume small to reduce the amount of waste.


Operators don’t have time to learn the extensive intricacies of a multi-valve panel. Low-e panels reduce this complication through simplified systems that are easy to use and save a considerable amount of time without compromising the sampling process.

Closed loop systems are designed to pull fresh material directly from the flow for the most accurate representative samples. Because of this, there’s no guesswork as to age or potential detrimental exterior impact. Test results are consistent and reliable. 

Low-e closed loop system considerations

Successful sampling starts with choosing the right system for your process. But there are a wide variety of low-e closed loop sampling systems and configurations on the market. Here are a few things to consider selecting the closed loop system for your process.

  • Pressure. Different processes require different pressure limits, from low vapor pressure to high-pressure liquids. Choose a system with a maximum pressure rating that meets your process requirements so you don’t exceed this limit.
  • Temperature. Some systems have minimum or maximum fluid operating temperatures. Like pressure, make sure you choose a system with a temperature rating that meets your process needs.
  • Construction Materials. Your sampling system must be constructed with compatible materials with your process fluids and gases to protect people and equipment at all times. Closed loop systems are made with proprietary components and designs to provide dependable systems that safely deliver sample accuracy. This includes surface treatments, which can reduce absorption and adsorption of the sample fluid for a more representative sample.
  • Purge. Purging the sample panel after the sample is secured ensures operator safety and minimizes loss of sample vapors to the environment. In addition, some chemicals might leave behind residue or contaminate the lines if not flushed from the system. A purge option allows you to extract a sample with a purge material, such as nitrogen, to ensure the cleanest possible sample.

Whether you are selecting a HTHV or a manual fixed volume sampler, making the correct considerations for your plant is vital to the efficacy of your sampling program and efficiency of your current and future processes. 

Need help selecting the right equipment for your plant’s needs? Contact one of our Low-Emission panel experts.

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Topics: Downstream, Liquid & Slurry, Gas