Process NMR

Crude Oil Blending Application

The Crude Blending Application is an attractive solution for refineries with the ability to blend different crude types to provide a consistent and optimal feedstock to refinery operations. Operating the refinery at optimal and constant crude composition can generate savings for major refineries on the order of 2% to 3% of the operating margin of the whole refinery. The Crude Oil Blending solution achieves this by:
Improved distillation unit throughput. Constant attention to the distillation quality of the crude loads the crude distillation unit and all the other downstream units consistently. This allows refiners to operate their crude distillation unit closer to its limits, which increases throughput. Improved higher value product yields. More stable and consistent operation allows operation closer to constraints. This enables the maximization of yields of higher value products.
Improved performance of downstream units. Specific characteristics of the crude will also influence performance of some of the downstream units. Changes in the ratio of paraffins to aromatics in crude, for example, will impact/affect the benzene, toluene, and xylene output of catalytic reformers.
Improved product quality and reduced energy costs. Stability of the crude composition also eliminates one of the major disturbance factors in a refinery, resulting in more stable operation. This contributes positively to overall quality, fosters efficient energy consumption, and improves equipment reliability.
Crude Oil Blending Application

NMR Application Details:

The process NMR component of the application for crude blending involves the correlation of NMR spectra to the following parameters:
  • API Gravity and Density
  • Water Content
  • True Boiling Point Values at ant temperature from C1 emission to 700°C
  • Viscosity
  • Pour Point
  • Sulfur
Studies have also been performed that allow the process NMR 1H Spectra predict various detailed average molecule parameters obtained from 13C NMR of the crudes studied. A listing of the parameters that can be correlated are given in Table 3 of the liquid-state applications page.

Below are several slides that show some of the details of the NMR application development:
Slide 1: Typical NMR spectrum variability observed for crude oils
 Typical NMR spectrum variability observed for crude oils
Slides 2 and 3: Typical processing scheme to allow prediction of water content, and then digitally remove water peak from spectrum to facilitate PLS modeling of other parameters.
Typical processing scheme to allow prediction of water content
digitally remove water peak from spectrum to facilitate PLS modeling of other parameters
Slides 4-8: Typical plots obtained from the PLS modeling of API gravity, sulfur and various key TBP points.
Typical plots obtained from the PLS modeling of API gravity, sulfur and various key TBP points
Typical plots obtained from the PLS modeling of API gravity, sulfur and various key TBP points
Typical plots obtained from the PLS modeling of API gravity, sulfur and various key TBP points
Typical plots obtained from the PLS modeling of API gravity, sulfur and various key TBP points
Typical plots obtained from the PLS modeling of API gravity, sulfur and various key TBP points
Slides 9-11:
Crude Oil Blending Application
Crude Oil Blending Application
Crude Oil Blending Application
For more information on Crude Assay Calculations follow the links below:
Z-Basic Assay - MS BasedHaverly Crude Assay LibrariesCrude Oil Fouling and Incompatibility
Crude Oil Fouling and Deposition 1Fouling 2

This application marketed by NMR Process Systems, LLC

For more information on this topic please contact:
John Edwards
Manager, Process and Analytical NMR Services
Process NMR Associates LLC,
87A Sand Pit Rd
Danbury, CT 06810, USA
Tel: (203) 744-5905
 
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