Instrumentation Level Measurement Solutions for Compressor Scrubbers
Natural gas can travel through thousands of miles of pipeline. In order to avoid pressure reductions and the resulting slowdowns caused by distance, friction, and elevation, natural gas must be pressurised. Compressors placed at key intervals keep the natural gas moving evenly and reliably. These compressors are generally grouped in stations, which are strategically located along the pipeline networks that transport and store the gas.
A typical compressor station consists of an inlet scrubber to collect liquids and slugs that may have formed in the gas pipeline. These compressor scrubbers have a primary section where liquids and solid parts are separated from the gas stream, and a secondary section where oil mist is removed.
This article, part of the Magnetrol series on level measurement solutions for natural gas processing applications, will discuss instrumentation that can help compressor scrubbers properly monitor the liquids they collect.
Level Measurement Challenges and Considerations
The liquids collected from the compressor scrubber are typically routed by way of scrubber level control valves to a low-pressure (LP) tank. The vapours produced from the flashing liquids are vented to the atmosphere or to a flare, and the low-pressure condensate is periodically trucked out. Scrubbers are often equipped with high and low level alarms. Instrumentation for monitoring compressor scrubbers must be able to accurately detect high and low levels and be able to withstand the conditions inside the tank.
Level Measurement Solutions
Magnetrol has produced level measurement solutions for compressor scrubbers:
• For point level:
Echotel Model 961 ultrasonic switch
• For continuous level:
Eclipse Model 706 guided wave radar transmitter
• For visual indication:
Atlas or Aurora magnetic level indicators
For more information on level measurement solutions for compressor scrubbers and other natural gas processing applications, download the natural gas processing brochure.