EMC based reliability enhancement of emergency shutdown in a natural gas liquefaction plant

PT. Badak NGL is a company that operates the largest LNG Plant in Indonesia with maximum LNG (Liquefied Natural Gas) production capacity 22.5 MTPA and LPG (Liquefied Petroleum Gas) production capacity 1.0 MTPA from eight (8) trains. Lightning is still considered as a potential threat for gas companies operating in tropical region well known with its high isokeraunic level, Its adverse effects could be harmful for the sustainability of production and leading to economical lost and hazardous situation. During heavy rainy season with relative higher lightning activity, the gas company of interest experienced spurious trips after lightning strikes occurred. This paper presents EMC-based approaches for enhancing the reliability of emergency shutdown in a natural gas liquefaction plant. The approaches provide comprehensively EMC measures from reducing the interference source until enhancing the immunity of the instrument apparatus so that EMI problems disturbing PLC ESD/EDP systems during lighting strike could be solved.