Lube Crude Selection

Lube oil manufacturers may have a lube cmde approval (LCA) process to assess the opportunity to manufacture Base stocks from cmdes available in 

With an acceptable assessment of the new crude, the refiner may elect to validate the crude for Base stock manufacture. This may entail running a plant test to make Base stock products from the new crude. The products made from the plant test are typically blended into formulated oils and subjected to testing to demonstrate acceptable product performance. 

Results of the plant test are reviewed with a focus on lube plant manufacturing performance and Base stock product quality to determine if the new erude can be approved for Base stock manufacture. 

1) Lube plant manufacturing performance - actual rate, yield and operability. The actual operating conditions are compared to the predicted processing conditions to assess if the new crude processed as expected. 

Results from the manufacturing test will determine if the crude will be accepted. The certification test must have been acceptable and the crude processed as expected. There must not be any evidence that Base stock quality is unacceptable. If the above is completed successfully, the crude may be approved and added to the manufacturer s list of approved crudes. 

---

A lube crude assay is a laboratory process to measure the lube processing response from crude to base oil. It is an important step in a manufacturer s lube crude selection. A crude assay will include process yields for desired base oils at their quality specifications. The manufacturer can use the assay data to predict the process response for their refinery and to assess the desirability of purchasing particular crude. The assay results may be used to calculate the impact on profitability. 

Cmde selection is extremely important for the profitable production of lubes. Only a limited number of crudes contain a sufficient quantity of lubes quality molecules. Downstream unit operability is affected by crude selection, as are rates and yields. Typically, manufacturers would prefer operating at maximum throughput, thereby spreading costs over a larger volume. Poor crude selection can result in downstream bottlenecks reducing overall throughput. 

Simple conventional refining is based essentially on atmospheric distillation. The residue from the distillation constitutes heavy fuel, the quantity and qualities of which are mainly determined by the crude feedstock available without many ways to improve it. Manufacture of products like asphalt and lubricant bases requires supplementary operations, in particular separation operations and is possible only with a relatively narrow selection of crudes (crudes for lube oils, crudes for asphalts). The distillates are not normally directly usable processing must be done to improve them, either mild treatment such as hydrodesulfurization of middle distillates at low pressure, or deep treatment usually with partial conversion such as catalytic reforming. The conventional refinery thereby has rather limited flexibility and makes products the quality of which is closely linked to the nature of the crude oil used. 

---