The incident happened at 8.50am and was reported by workers and residents in the Dalmeny and Cramond areas.
Wullie Ruffle was working at Barnbougle Castle, in the Dalmeny estate, when he and a colleague heard a “roar” that lasted several seconds.
“It shook the foundations,” he said. “All the seabirds rose as one. We rushed down to the waters edge. It was the loudest bang I’ve ever heard.”
Mr Ruffle, secretary at the Dalmeny Estate golf club, described the noise as coming from the direction of the Hound Point loading jetty, which lies upstream from the Forth bridges.
One woman making her way to work also reported hearing an “unusually loud bang” while waiting at a bus stop near Cramond Brig.
A spokesman for energy giant Ineos, which owns the facility, reported all operations at Hound Point were normal and said the incident had nothing to do with the site.
Emergency services said they had no record of any call outs in connection to the incident.