For refiners, opportunity crude is crude oil available on the spot market that are typically much lower cost than crude oil received under long-term contracts.
In a Hydrocarbon Engineering article, Finding the Sweet Spot, Emerson’s Meha Jha and Julie Valentine collaborated with Topnir Systems‘ Didier Lambert, to highlight the processing challenges for opportunity crudes and solutions to address these challenges.
They open describing the challenge in processing opportunity crudes.
As using expensive crudes can limit the profit margins of a refiner, there is a trade-off between the cost of crudes and the risk of operational impacts they can have on the process.
If the opportunity crudes are not blended to the right ratios for which the refining process has been designed, these operational impacts can include:
…risks such as corrosion, fouling, bottlenecks and slowdowns.
They provide an example of what the use of operating crudes can financially deliver.
An increased usage of just 1% of opportunity crudes could save US$5 million for a 250 000 bpd refinery at a differential of US$6/bbl…
Even the composition of long-term suppliers of crude can change.
Furthermore, crude assays from known suppliers are not always consistent as changes in the conditions at the source can affect the crude over time.
Crude assays, lab analysis and tank blending are the traditional ways to find and change the characteristics of the crude oil, such as its API gravity, acidity, sulfur content, etc. To avoid some of the operational impacts, refiners are looking to more automated and continuous ways characterize and blend the crude oil.
These changes include adopting technology to provide online crude characterization and inline blending to accurately measure each component according to a target recipe, enabling real time blend adjustments based on the online crude analysis.
Instrumentation such as [hyperlinks added for more information]:
Flow, density and viscosity meters can confirm simple characterisations. Topology and near-infrared (TopNIR) analysers and models can be used for full characterisation.
Simple characterizations include crude oil density, viscosity and water cut. Full characterization includes:
…API gravity, sulfur, temperature boiling point curve, TAN [total acid number], carbon-hydrogen ratio, asphaltenes, and yields.
Models help to allow fewer samples to be required to interpolate compatible crudes by providing:
…a library of crude clusters grouped by chemical characteristics and properties.
Read the article for more on how the simple and full characterizations combined with advanced process control can help maximize the use of opportunity crudes and avoid the operational impacts of non-compatible crude blends.
Visit the Refining section on Emerson.com for more on the technologies and solutions to drive top quartile performance. You can also connect and interact with other refining industry experts in the Refining group in the Emerson Exchange 365 community.
