Case Three

MOL and Terminal Measurement Survey, Oman

Requirement 

Investigate the terminal balance for the MOL (Main Oil Line), storage tanks, refinery supply and returns, and sea tanker loading. Survey each MOL entry meter at 41 locations to estimate the regional and pipeline balance and uncertainty. 

Solution 

The project was undertaken in three stages comprising terminal balance, pipeline balance and analysis of the regional balances. The terminal balance uncertainty was examined and the uncertainty estimate used to provide a balance acceptance criteria for daily, weekly and monthly reporting. The MOL import meter was compared with a pipeline meter in the interior and calibrated using storage tanks for use in the terminal balance. 

MOL meters in the interior were surveyed for the three regions comprising LACT units with a  prover and PD or turbine meter, uncompensated orifice with (square, conical and quadrant) meters, venturi, vortex, coriolis, ultrasonic (single, multipath and clamp on) and storage tanks at each location. An allocation model for the MOL and terminal was developed to find the allocation uncertainties and pipeline balance uncertainty using survey findings.