Bapco the National Oil Company (NOC) for Bahrain, first discovered oil in the Arabian Peninsula in 1932, exporting in 1934 and finally refining in 1936. With over 80 years’ experience in all things oil, the refinery now is at 265 MBPD and one of the biggest exporters of oil in the world.

The refinery is a lead producer high value, low sulphur products and the need for such products saw the inauguration of the Low Sulphur Diesel Production Complex (LSDP) in 2007.

At the heart of the complex was a new heavy vacuum gas oil (HVGO) hydrocracker (1HCU) processing HVGO feedstock. The new unit was able to run a processing capacity of 50k barrels per day (BPD) and with the addition of a twin reactor system, is capable of running at 80% conversion. The focus on high value, low sulphur products included the increasing need for commodities including:

• Naphtha
• Kerosene
• Low Sulphur diesel

At the beginning of summer 2016, the combined and worsening effect of a series of events resulted in Light Naphtha hitting maximum rundown temperatures and threated to force a slowdown of 1HCU, these included:

• naphtha production yield was near maximum due to higher 1HCU throughput and the catalyst being close to End of Run (EOR) which required conduction of the reactor at higher temperature
• the seawater cooling capacity had decreased due to inherent hydraulic limitations in the Low Sulphur Diesel Production (LSDP)
• ambient temperatures were high and increasing
• the Light Naphtha rundown temperature limit had been marginally reduced as a result of a process safety review
• exceeding Light Naphtha maximum allowable run down temperature implied, for safety reasons, turning down the unit throughput with consequent loss of production

Bapco needed a solution which would effectively and safely remove the Light Naphtha. By cooling it, this would eradicate bottlenecks from forming, allowing production to continue safely.