Overview
Crude oil and refined product pipeline in the oil & gas industry
Separate recording of flow systems
Large diameter pipelines offer the most efficient way to transport oil products to and from a refinery. Crude oil can come directly from the production location, or from the tank farm where it arrived by ship. Pipelines are also used to transport the resulting refined products to another tank farm, which is typically close to the refinery, but could be up to several hundreds of kilometers away.
The pipeline operators are not necessarily the owners of the product inside the pipeline. There are for example companies that transport crude oil from a sea harbour terminal to several different inland refineries located along their pipeline system. This makes accurate measurement of what enters and leaves the pipeline of key importance. In addition the operator needs to have an effective pipeline leak detection system for security and safety. The suppliers of the product, and their customers, need to measure what is delivered into the pipeline, and what the customer receives. Inaccurate measurement cannot be tolerated, as relatively small errors might have large financial implications, so the highest accuracy custody transfer pipeline metering systems are used.
The flow measurement systems at the inlet and outlet points of a refinery usually consist of multiple (duty) meter runs in parallel: each meter run has two separate flowmeters to provide two separate records of any delivery, as a cross-check. Additionally there can be a master-duty Z-configuration of the pipework, and/or a prover installation, to enable in-line verification of the duty meters. Such custody transfer systems are usually supplied as a complete skid, which can also include items such as degassers and an analyzer or sample grabber.
KROHNE has a vast experience with measurement systems for crude oil and refined products. The product range starts from Ultrasonic and Coriolis flowmeters specially developed to meet the high accuracy needed for custody transfer duty, up to fully engineered metering skids and analyzer houses. For the tank farm control system KROHNE supplies radar level transmitters and high and low level switches: in addition the PipePatrol system provides a pipeline leak detection system for oil and gas flow lines.