Improved Fouling and Corrosion Control in New Ethane Cracker Reduces Operating Expenses By $1.4 Million per Year.

Braskem Idesa, in collaboration with Dorf Ketal and Solenis, reports on steps taken to improve efficiency and reliability of Cracked Gas Compressor (CGC) and downstream units at the Coatzacoalcos, Mexico ethylene plant. This ethane cracker, commissioned in 2016, started with wash oil and wash water as additives to control CGC fouling. Compressor fouling issues led to a change in wash oil treatment that improved fouling control in the compressor, but created an emulsion in the CGC knock-out drums. This emulsion caused corrosion and fouling problems in the Dilution Steam Generator and Quench Water systems, increasing costs for energy, reboiler maintenance, filter replacements, and effluent treatment. This paper discusses actions taken to reduce operating costs by an estimated $500,000 per year without capital investment. Root cause analysis, and modifications in cleaning procedures, monitoring, and treatment chemistry are presented.