Opportunity 29: Optimisation of the MEG regeneration unit

Optimising the reflux rate to minimise losses of MEG from column.
MEG distillation column is designed for constant reflux rate. The measure consists of defining optimal reflux rate for varying feed rates to the distillation column so that losses of MEG from the column are minimized.

Process to get there: Desire to improve energy efficiency and minimise loss of MEG.
The measure’s technical lifetime: The complete field’s lifetime, 40 years+.
The investment is time spent for process engineers, laboratory technicians and operators.

Results:

  • Earnings: Saving 0.25 MNOK/year in carbon quotas (CO2 emissions trading fee for onshore facilities 1 quota = 1 tonne). Increased loss of MEG is 0.2 MNOK/year.
  • Sales of extra gas 1.85 Msm3/year (11 % reduction in fuel gas)
  • Emissions effect: 3 700 tonnes CO2/year (6 % reduction), and 3.9 tonnes NOx

Shell has implemented this improvement opportunity on Nyhamna.
System group: Export and by-product handling (30-39)
Type: Operations optimisation Investment: Not quantified
Profitability: Profitable Implementation: Implemented