LONDON (Reuters) - Global energy trader Vitol said on Friday its 2019 revenues were $225 billion (184 billion pounds) and its traded oil and refined products volumes rose by 8%. Chief Executive Russell Hardy said last year's performance was "solid", as the company's traded oil volume hit 8 million barrels per day (bpd), up from 7.4 million bpd in 2018."Across the barrel, margins were favoured by a relative tightness, enabling us to optimise performance ... Most products benefited from these..