Project Description

The EVA production plant of Formosa Plastic Group is a chemical facility dedicated to producing ethylene-vinyl acetate (EVA) in various production grades.

EVA polymerization takes place in a long tubular reactor (1,400 meters) that requires very specific conditions, based on stable pressure and temperature within the reactor.

In addition, periodic rapid gas expansions are required for two distinct purposes:

1. To stop the reaction: This periodic depressurization halts the reaction, preventing uncontrolled increases in reactor temperature.
2. To remove pipe fouling: The sudden depressurization causes gas expansion, which increases gas velocity. This high-speed gas helps remove adhered product from the inner layer of the reactor piping.

In this specific process, maintaining a tightly controlled pressure drop is also required to ensure the reaction is not interrupted for too long, which could cause production losses.

The pressure drop is controlled by the time the reactor export valve remains open. This timing is managed by DCS operators, who manually adjust it in 20 ms increments to increase or decrease the depressurization duration.

CPC implemented an algorithm that automatically regulates this timing, keeping the pressure drop within the required limits (as defined by the operators), thereby ensuring continuous production optimization.

Along with this improvement, CPC Engineering installed our fast monitoring tool in the control room, ensuring ultra-fast data recording (below 50 ms), which is critical for monitoring and troubleshooting in this type of process.