A large-scale water injection system in the Middle East used compressed natural gas to lift water from the aquifer to inject into the oil formation to maintain pressure of the reservoir.

Six million barrels of water (250 million gallons) were processed and injected every day. While a short period of downtime didn’t affect oil production, more than a day could decrease production by 0.5 percent, which was worth $10 million per day in lost revenue.

The supplied sour gas contained hydrogen sulfide (H2S), which needed to be removed to create sweet gas that would not corrode pipelines, compressors and wells. The gas was sweetened using a glycol-amine process.

During a routine planned gas sweetening plant shutdown, all the glycol pump seals were replaced. Two days after start-up, all the pump seals leaked profusely, causing a shutdown of the plant for a full day.

Realizing all the seals leaking was more than a coincidence, the maintenance engineer and mechanical foreman took a close look at the seals and discovered that the O-rings that sealed the assemblies were disintegrating and gummy. Assuming they were not glycol compatible, they got new seals from local emergency stores. The plant came back on line and ran leak free.

A root cause analysis found that procurement had ordered generic seals to save money. The seals were the right dimensions, but the wrong material.

The dollars saved on the seals were offset by the millions of dollars in downtime.

Procurement had not contacted the stakeholders prior to making the change.

Data governance and management of change (MOC) procedures were developed to prevent
future errors.