Full Conversion Refineries

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MCE offers full conversion refineries along with auxiliary, utility and offsite units to standard sizes with single point responsibility. The full conversion refinery adds bottom upgrade units to the hydroskimming refinery to convert low value heavy products into high value automotive fuels.

Standard Sizes

Major Units


Vacuum Distillation (VDU)

The atmospheric residue is processed in a vacuum tower to separate the gasoil and residue. Preheating sections of CDU and VDU are fully integrated in order to maximize heat recovery and minimize fuel consumption. From the vacuum tower overhead, vent gases are routed to a fired heater, steam condensate is sent to the Sour Water Stripper and the vacuum gasoil stream (VGO) is sent to hydrocracking unit, distillate hydrotreater unit or light crude storage.


The vacuum gas oil from the VDU is fed to hydrocracking unit for conversion into lighter products LPG, reformer grade Naphtha, ULSK (Ultra low sulfur kerosene) and ULSD (Ultra low sulfur diesel). The hydrocracking process occurs in presence of a catalyst in a hydrogen rich environment at elevated temperatures and pressures.  In this process, the high-boiling, high molecular weight hydrocarbons are cracked into lower-boiling, lower molecular weight hydrocarbons while sulfur and nitrogen present in the hydrocracking feed are removed.

Fluid Catalytic Cracking

The vacuum gas oil from the VDU is fed to fluid catalytic cracking unit to maximise gasoline production. In FCC, a fluidized bed of catalyst particles is brought into contact with the feed along with steam injection  for stripping out hydrocarbon vapors associated with catalyst. Alkylation unit is used to convert light olefins, produced by an FCC or Coking unit into a gasoline blending component called alkylate. Consisting of branched chain paraffinic hydrocarbons (iso-heptane and iso-octane).  Alkylation unit is considered only when the FCC unit has been selected for bottoms up gradation.


The vacuum gas oil from the VDU is fed to the visbreaker, which thermally cracks large hydrocarbon molecules into naphtha, gasoline and residue by heating in a furnace.  The cracked products are quenched with gas oil and flashed into a fractionator to separate light and heavy streams.


The residual product from the VDU is fed to the coking unit at high temperature and low pressure. Coking is a thermal cracking process used to convert low value residual fuel oil to higher-value gas oil and petroleum coke. The residue is fed to the bottom of fractionator where light ends are stripped to the maximum extent.

MCE Consulting Engineers