Quantification of oil droplets under high pressure laboratory experiments simulating deep water oil releases and subsea dispersants injection (SSDI)

Limited experimental and field data are available describing oil droplet formation from subsea releases at high pressure. There are also analytical challenges quantifying oil droplets over a wide size and concentrations range at high pressure. This study quantified oil droplets released from an orifice in seawater at low and high pressure (5 m and 1750 m depth). Oil droplet sizes were quantified using a newly developed sensor (Silhouette camera or SilCam). The droplet sizes measured during experiments at low and high pressure, using the same release conditions, showed no significant difference as a function of pressure. This lack of a pressure effect on oil droplet sizes was observed for both untreated oil and for droplet formation during subsea dispersant injection or SSDI. This strongly indicates that the effectiveness of SSDI is not influenced by water depth or pressure, at least for simulated subsea releases of oil alone (no gas). •Limited data exists on oil droplet formation from subsea releases at high pressure.•Experiments were performed at pressure corresponding to 5 and 1750 m depth.•No significant difference in oil droplets sizes was observed at high & low pressure.•This was also observed during dispersant injection (1 & 2% dosage).•This indicates that dispersant injection effectiveness is not dependant on pressure.