Making Level Measurements in a Crude Oil Separator

Making Level Measurements in a Crude Oil Separator

Remember the old saying “oil and water don’t mix”?

Well they don’t, but that doesn’t mean separating them is easy.

In the oil and gas industry, where increasing efficiency is key, keeping the two apart can be a challenge, but one worth overcoming.

An emulsion layer – also called a rag layer – is an area where two liquid products, such as oil and water, have not fully separated. The thicker the layer becomes, the more challenging it can be to measure the true interface level.

A separator removes water from crude oil. The oil floats on top, while water is removed from the bottom. Measuring the oil-water interface is critical to keep oil from being sent to the water processing system.

An emulsion layer between the oil and water can interfere with level measurement. Guided wave radar technologies are best suited for clean interface level applications or where very little to no emulsion/rag layers are present.

Capacitance level measurement is based on the change in capacitance in a vessel, normally due to the change in the level of the liquid. Therefore, when dealing with oil/water emulsion layers, capacitance technology is the preferred technology.

To address this, guided wave radar limitations, a dual technology measurement device combining guided wave radar and capacitance, is best suited for this application.

For example, a leading oilfield exploration company was having issues with a standard guided wave radar device installed in a separator to measure overall and interface level.

A multiparameter level device combining guided wave radar and capacitance sensing technology was installed in the separator and immediately delivered excellent results.

Whether there was a clean interface or an emulsion layer, the device reliably measured both the overall and interface level, providing the customer with the measurement information required to accurately separate the oil from water and maximize their crude oil production.

The customer now has a reliable interface measurement at all times – even with the formation of a thick emulsion layer – and the efficiency of the separator was increased.

This provides better oil recovery without getting water into the oil, or oil into the water

To learn more about oil and gas solutions that enhance oil recovery and optimize operations, please visit us at booth 11307 during the Offshore Technology Conference 2016 May 2-5 in Houston, Texas.

Lee Lindsay
Posted April 27, 2016 By Lee Lindsay, Industry Manager - Oil & Gas, Endress+Hauser Inc.
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