Compressors are some of the main equipment in ammonia plants since the ammonia synthesis reaction requires a high pressure to achieve the intended conversion. With high-speed rotation, compressors are equipped with sealing systems, commonly Dry Gas Seals (DGS) to minimize the gas leakage and a lubrication system to reduce friction. Separation gas (Nitrogen) is injected in between to prevent lube oil contamination to the DGS system.
A failure in the DGS system at PT Kaltim Parna Industri (KPI)’s ammonia plant led to the creation of an explosive atmosphere in the lube oil reservoir, despite the presence of an inerting. The risk of explosion is significant when the leakage gas is hydrogen, which is broadly known to have a wide explosive range with a very low ignition energy. KPI has experienced some DGS failures within its 20 years of operation.
By implementing proper risk assessment using inerting methods, identification, and assessment to the potential ignition source, KPI has safely maintained a non-flammable atmosphere and prevented a major fire and/or explosion in the lube oil reservoir of the compressors.

This paper was a standby paper of the AICHE Ammonia Safety Conference 2023 in Munich.