Oil and gas extraction. Refining

Nitrogen

Nitrogen reinjection is presently the most-commonly used approach to Enhanced Oil Recovery. When it is necessary to drill wells in marshy areas, liquid nitrogen is used to stabilize the soil by freezing it. As an inert gas and an oxygen-displacing gas, nitrogen is used to clean LNG tanks and reservoirs, to purge process systems and refinery piping; it is also used for the preservation of equipment and for pressure testing pipeline systems. As an oxygen-displacing and non-flammable gas, nitrogen is used in safety systems, e.g. explosion-proof and fire-extinguishing systems.

The basic nitrogen applications are:

• Well stimulation
• Soil stabilization during well drilling
• Cleaning tanks and reservoirs in LNG carriers and storage facilities
• Purging of process systems and refinery piping
• Preservation of process systems and refinery piping
• Pressure testing of pipeline systems
• Protection against explosions and combustion
• Fire-extinguishing systems

Oxygen

In the oil and gas industry oxygen is used in refinery and in gas processing. Oxygen pressurization is a well-proven method for improving the efficiency of industrial equipment.

Oxygen pressurization is also used to reduce the amount of flue gas and to increase the conversion ratio of the reaction. In liquid-phase catalytic cracking units, oxygen enriched air is used to increase the efficiency of the catalyst regeneration process. It is not unusual to see an increase in the catalytic cracking unit capacity from 10% to 30%, and in the processing of the residuals an increase up to 40%.

To sum up, oxygen is used in the oil and gas industry to:

• Reduce the amount of flue gas
• Increase the conversion ratio in the refinery process
• Increase the efficiency of catalyst regeneration in liquid- phase catalytic cracking units