Process Technologies

HyDeWAX™

HyDeWax™ is a two-stage process.

During the initial stage the cold flow properties of the UCO (unconverted oil) produced in the hydrocracking reactor or the hydrorefined VGO are improved through hydro-isomerization reactions of the n paraffins. The n-paraffins have poor cold flow properties, the hydro-isomerization step improves the lube base oil cold flow properties considerably while reaching higher yields than with a conventional solvent process scheme. During the hydro-finishing stage, aromatic molecules are saturated and the color and stability of the oil are brought to specification.

HyDeWax™ can also upgrade 100% wax feed in order to produce high quality lubes.

Lube Hydrofinishing

The target of Axens Hydrofinishing process is to adjust color and stability requirement for motor base oils. In that purpose, polar compounds (oxygenate, unsaturated, ...), responsible for both brown color in lubes and instability, are hydrogenated.

This process uses classical desulfurization catalysts in low severity operating conditions (low temperature and low hydrogen partial pressure).

Lube Oil Hydrorefining

The hydrorefining/hydrocracking scheme for lube base oil manufacturing has many advantages over the conventional solvent process scheme:

• Higher flexibility
• Higher yields of high-value, high-quality lube base oils
• Higher viscosity index: between 95 and 145
• Production of high-quality fractions: gasoline, jet and diesel fuel
• No wax production

HyK™

HyK™ is Axens high conversion Hydrocracking technology that converts middle distillates or heavy distillates into more valuable products. Apart from the conventional Straight Run VGO, other feeds that could be processed in a hydrocracker includes:

• Heavy Coker Gasoil (HCGO) produced from Delayed coker or Flexicoking process,
• Deasphalted oil (DAO) from SDA,
• VGO cut produced from Resid hydrocracker (ebullated bed or slurry technology),
• Straight run kerosene and diesel,
• LCO coming from FCC,
• LCGO from coker.

In order to adjust the product yields and meet the most profitable production targets it is necessary to choose the right process scheme for each project:

• “Once-Through scheme” offers the possibility to produce middle distillates and valorize the VGO feeds as top-quality Group III lubes or petchem feedstock,
• “Single Stage with Recycle scheme” boosts the conversion and selectivity towards valuable fuels with moderate increase of the investment cost,
• “Two-Stage scheme” offers the best selectivity towards high-value middle distillates or naphtha for petchem while minimizing the unconverted bleed.

Prime-D™ with cracking

While having to handle heavier diesel cuts, the refiner has to address the demand for more gasoline for the fuel market or for petrochemicals production downstream.

Consequently, the middle distillates hydrotreatment target is evolving to bring sufficient flexibility to the products properties as well as yields adjustment. To this end, deep optimization of cracking and hydrotreatment catalyst systems are required.

Prime-D™ with cracking is the optimal solution when deep hydrogenation is not enough to reach stringent specifications on density and/or cetane for refractory feedstocks, or when additional gasoline production is desired.

Prime-D™ with dewaxing

In addition to reaching ultra-low sulfur content, cold flow properties and specifications of the diesel product may have to be improved due to local climatic constraints.

Prime-D™ with dewaxing is a competitive alternative for cold flow properties improvement as compared to more costly options such as feed undercutting, kerosene blending, or chemical additive addition, leading to high operating costs and loss in diesel yield.

Conventional Prime-D™

Conventional Prime-D™ ensures achievement of ultra-low sulfur diesel (ULSD) specification, density and cetane improvement over a large range of diesels cuts: from straight run to large cracked feedstocks.

Prime-K™

In case sulfur content of kerosene feed is above 0.3%wt, and/or smoke point and/or freezing point of kerosene has to be improved to meet jet A1 specification, or even if flexibility is envisioned to send kerosene to diesel pool at 10ppm of sulfur content, Sweetening process is no more the solution, but Prime-K™ is.

The objective of the Prime-K™ process is mainly to reduce the total sulfur content of the kerosene cut and, if necessary, the aromatics content in order to improve the product smoke point, to produce jet fuels.

Sweetn’K™

Sweetn'K™ converts Mercaptans directly to RSSR and is used to treat Kerosene through a catalyst fixed bed of SCPS-ready allowing to comply with JET-A1 specification. The unit is made of 3 sections:

• A front prewash section, which neutralizes aliphatic acids.
• The reaction section where an oxidation reaction converts mercaptans into disulfides. The reaction between mercaptans and air occurs in an alkaline environment in contact with Axens Solutions catalyst “SCPS Ready”.
• In the finishing section, the kerosene is dried by a water removal mass and finally upgraded on a clay bed to improve product color.

This process features mild operating conditions:

• Low pressure
• Ambient temperature

Hexorb™

Ultimately, to go beyond the 90 RON threshold, substantial conversion of the methyl pentanes is required. This can be achieved with full conversion of normal paraffins by integrating the Hexorb™ separation process with the reaction section. This process combines a cyclic molecular sieve adsorption system with a downstream de-isohexanizer that splits raw isomerate from the molecular sieve section into an isomerate overhead stream rich in isopentane and dimethylbutanes and poor in the lower octane methylpentanes (MPs) from two streams containing heavier components.