ProDecon® Case Studies

ProDecon was asked by a steel producing company in Middle East to decontaminate the CO2 absorption system on their Direct Reduction Plant (DRP). As a by-product of the process hydrogen sulphide gas is produced and found in the Amine system. Combined with iron, this produces pyrophoric iron sulphide which accumulates in the stripper and absorber columns. When exposed to atmospheric oxygen a strong exothermic reaction is initiated which releases toxic gases. If the reaction cannot be controlled or stopped, it has the potential to permanently damage the equipment and has been known to cause columns to collapse. Previous attempts to complete these works by other contractors had been unsuccessful with violent pyrophoric reactions evolving significant toxic vapour and preventing planned maintenance works.

The target of the works was to provide a safe working environment for the subsequent maintenance works with no H2S and no pyrophoric materials. In addition to the safety requirements for maintenance, the process should ensure the amine solvent used in the absorption process did not foam on startup, a notorious problem in these systems.