The ILBOC plant consists of two main process units:
- The Vacuum Distillation Unit (VDU).
- The Catalytic Dewaxing Unit (CDW).
In the Vacuum Distillation Unit our raw material, UCO (Unconverted Oil), is processed, having previously come from the Hydrocracking units at the Repsol refineries.
This raw material is characterized by being highly paraffinic with a high viscosity index and low aromatic compound content, sulphur, nitrogen and metals.
In this unit, the raw material is fractionated in a distillation tower that operates under pressures lower than atmospheric pressure in order to avoid losses and degradation of product, obtaining different distillates according to their viscosity.
These distillates are stored in tanks, later to be processed in the Catalytic Dewaxing Unit.
The Catalytic Dewaxing Unit consists of two main sections:
- The reaction section.
- The fractionation section.
This unit is loaded, in batches, with the different distillates obtained, depending on the lube base oil that one wishes to obtain.
In the reaction section, which operates at high pressure and temperature conditions, the paraffins present in the raw material are isomerized, thus improving their cold properties without losing their main characteristics of viscosity and lubrication capacity. In addition, impurities such as sulphur and nitrogen are removed, and the low content of aromatic components present in the raw material is saturated, thereby improving the oxidation stability of the lubricant base.
Finally, in the fractionation section, the lighter components of the product which have passed through the reaction unit are removed to meet the final specifications of the lubricating bases.