The sulphuric acid production plant is based on the vanadium and caesium contact catalytic process.

During the first process phase, the combustion of the liquid sulphur takes place in dry air to obtain a blend of sulphurous oxide gases, which are then cooled down in a fire-tube boiler to produce steam as a result of the heat generated by the sulphur and sulphur dioxide (SO2) exothermic reaction. The produced gas is sent to the four-stage catalytic tower, to recover the additional heat obtained from the sulphur dioxide (SO2) and SO3 exothermic oxidation reaction.

The SO3 is then absorbed in water to produce sulphuric acid (H2SO4), which can in turn absorb more SO3 to produce oleum at different concentration levels, according to the market requirements.

The process steam is overheated and sent to the turbines to generate power that is sent to third parties, after making sure that the needs of the Trecate factory are met.