Inert gas is used for blanketing and purging of chemical tanks, and for purging of equipment and systems before maintenance in Semco Maritime’s efficient system, named SemN2.

The inert gas system can be divided into three sub-systems:

  • Nitrogen generator / source
  • Storage system
  • Distribution system

Typical operating / design conditions

Typical supply pressure is 6-9 barg when using plant air feed.

Typical design and operating criteria for the main equipment:

  • Feed air pressure 6-10 barg
  • Feed air temperature 30°C-50°C
  • Feed air particle size 3 micro meter
  • Feed air dew point (at 10 bar) -25°C
  • Oil free feed air Less than 0,01 mg/m3
  • Design pressure 8-13.5 barg
  • Design temperature, min/max -10°C / 60°C

Typical consumers

Nitrogen is used extensively for drilling, completion and workover of oil and gas wells, also for pressure maintenance and gas storage in condensate formations.

It can be generated on site at high pressure and low oxygen levels to safely prevent ignition of flammable gases or protection of field tubulars from downhole corrosion.

Consumer description:

  • Produced water flash drum
  • Compressor gas seals
  • Produced water disposal caisson
  • Heating medium expansion vessel
  • Methanol storage tank
  • Low-pressure flare header
  • Atmospheric vent header
  • Hazardous open drain sump
  • Closed drain flash drum
  • Reclaimed oil sump
  • Heave compensation