Oxygen for crude oil refineries
In crude oil refineries, oxygen is used for partial heavy crude oil part oxidation, catalyser regeneration in the FCC units, as well as for the desulphurization unit performance increase (Claus units).
In the Claus process, hydrogen sulphide is converted into elementary sulphur. The sulphur compound removal is prerequisite for further crude oil, natural gas, and coal processing to fuels, synthetic gas and fuel gas.
The target of this process is the adherence to the prescribed emission limits and technological requirements for the subsequent chemical treatment.
Currently, mainly airborne oxygen is used for hydrogen sulphide oxidation.
Should oxygen be injected into the air feeding pipeline, or should pure oxygen be used, the following effects may be reached:
– Equipment capacity enhancement
– Temperature increase in the combustion chambers
– Off-gas volume reduction (due to the inert nitrogen concentration reduction in the air)
– Newly constructed units might be smaller and more effective
Hydrogen for crude oil refineries
Crude oil refineries are both producers and consumers of hydrogen; hydrogen consumption is usually higher than their own production.
Refineries consume hydrogen mainly as reactant for hydro treating and hydro cracking technique. As the portfolio of products which are produced in refineries, is always more often focused on products that have lower sulphur and aromatic compound contents, as well as on the lighter product fraction, hydrogen consumption will continuously grow in the refineries.
Main hydrogen production technologies:
– Methane steam reforming
– Crude oil treatment residual gasification and hydrogen production from the synthetic gas
– Hydrogen recovery from refinery off-gases