Revenues at the Aughinish Alumina refinery last year increased by 15% to $757.1m (€684m) in spite of US Treasury sanctions imposed on the Limerick company’s parent firm.
The US sanctions were lifted earlier this year and new accounts for Limerick Alumina Refining Ltd (LARL) show that in spite of the higher revenues, pre-tax profits at the company last year decreased by 19% to $40.9m.
During the time of the sanctions, the US Treasury permitted Aughinish Alumina's owner, the Rusal Group to continue operating by issuing a number of general licences to it.
The drop in profits at the Co Limerick firm came as a result of increased costs.
The principal activity of the company is the production and sale of alumina and the company said "the favourable market environment for the alumina industry in 2018 resulted in the company recording a profit of $40m".
The production output at the plant located on the Shannon estuary in 2018 was 1.81m tonnes of alumina.
But, costs at the plant last year increased by 18% from $606.53m to $715.2m.