Fixing the Three Most Common Problems with Hydrocarbon Process Sampling

Manual process sampling plays an important role in controlling product quality, detecting corrosion and ensuring processes are operating as expected. But it doesn’t always get the attention it deserves. That can lead to unrepresentative samples, frequent maintenance issues with sample panels and unnecessary exposure of operators to spills and emissions.

If you’ve experienced any or all of these issues, the solution may be simpler than you expect.

1: Unrepresentative Samples

Pulling unrepresentative samples is not the fault of the operator doing the sampling. It often represents an inherent design flaw in many sampling panels. When sampling liquids in hydrocarbon processing, the sample panel is connected to the process by a bypass. When the operator turns a handle on the panel, a valve in the bypass is opened and process material is diverted into the sample container.

It sounds simple, but the valves in some panels block process flow through the bypass when closed.  When the operator opens the valve, they end up collecting “stale” process material that may have been sitting in the bypass since the last sample was taken. Obviously, that sample is not going to represent current process conditions.

To get fresh, representative samples use a sample panel with a flow-through valve design. These valves allow process material to move through the bypass continuously so that when the valve is opened, and the material is diverted into the sample container, it represents what is actually moving through the process at the time the sample is taken.

2: Frequent Panel Failure

We all know that without regular maintenance, a mechanical system will break down more frequently. It’s also much more expensive and disruptive to repair a broken system than to identify and resolve potential problems through preventive maintenance.

That’s as true for sample panels as it is for any other systems. Yet, too often, busy employees prioritize other tasks ahead of panel maintenance, or just assume the responsibility for maintenance lies with someone else, and panel maintenance gets neglected.

Regular visual Inspections of sampling panels are the first step in avoiding a crucial breakdown. It doesn’t take a lot of time, but it does require some expertise as you need to be able to identify signs of wear, leaks, abrasion or chemical attack of components. Less frequently, but regularly, you should also clean and lubricate components and replace worn seals and gaskets as necessary. Just performing those simple processes can help extend the life of your sample panel and minimize unexpected failure.

Organizations that lack the capacity or expertise to conduct regular inspections and maintenance can contract this activity to a third-party. This ensures a disciplined, expert approach to panel maintenance while documenting each inspection with a detail service report. But not every sample panel provider offers on-site maintenance services, so ask about maintenance capabilities before choosing a provider.

3: Operator Exposure to Emissions and Spills

Operator safety should always be the number one priority of any sampling program. Again, sample panel design can make a huge difference. Sampling high-temperature and other materials with an open sample panel can expose the operator—and the environment--to spills and emissions.

To protect operators from these hazards, use a fully enclosed sample panel in cases where spills or emissions could harm the operator. These panels keep liquids and gases fully contained throughout the sampling process, isolating operators from contact with high pressures, temperatures and volatile gases. A clear window in the enclosure allows the operator to visually monitor the collection process.

If you’re going to do manual process sampling—and you need to for multiple reasons—you might as well do it right. For more on best practices in hydrocarbon sampling, download the Sentry e-book, Process Sampling 101: Five Things to Know When Sampling in Hydrocarbon Processing. 

From the Archive