Gunvor Group chief executive Torbjorn Tornqvist has revealed a dismal forecast for the refining sector, but said its ships have been making plenty of money this year.

In an internal memo to staff seen by Bloomberg, the billionaire founder of the trading giant said he expected "brutal" refining margins to persist for many years.

Gunvor has previously said it is considering shutting down its refinery in Antwerp, as it continues to lose money.

Tornqvist worked there more than three decades ago. He said trading and chartering profits during the first half would more than offset any impairment charges if it does close the plant down, however.

He also told staff the group had prospered during the oil price crash earlier this year, with trading and shipping operations booming. Gunvor is parent of tanker operator Clearlake Shipping.

"Gunvor managed to navigate very well through the downs and ups and got it basically right," Tornqvist wrote.

As oil briefly traded below $0 in April, the Swiss group filled its storage tanks with cheap crude and sold forward futures at higher prices in the contango conditions.

Rates bonanza

Gunvor owns or operates more than 100 vessels.

The trader profited from booming rates as tankers were booked for storage contracts.

"Given our sizeable fleet of ships under management, this allowed for substantial earnings for the [second] quarter," Tornqvist wrote.

Rival traders Trafigura and Mercuria Energy have also been making big money during the crisis.

Mercuria told bankers on a recent loan call it logged a record $425m in net profit in the first six months.

Trafigura also reported record results from trading in the first half, helped by its tanker fleet and stakes in profitable shipowners Frontline and Scorpio Tankers.

Gunvor said net profit in 2019 was $381m.