Background

Petrochemical plants and refineries operate in an integrated manner, utilizing by-products from the refining process as feedstock for various applications. One crucial step involves the refining of pyrolysis gasoline, known as pygas, in Moerdijk Chemical Plant. The by-product which then acts as feedstock for the petrochemical complexes undergoes a series of operations, depending on the end-use product requirements.

Pygas hydrogenation is a pivotal step that involves saturating olefins and diolefins present in pyrolysis gasoline, a by-product derived from steam cracking. Simultaneously, aromatic extraction utilizes extractive distillation to isolate benzene from the hydrotreated pygas. The nature of pygas processing poses challenges (temperature fluctuations, heat effects,etc.) due to its reactive properties, necessitating a vigilant real-time monitoring system. The deployment of a robust solution is imperative, involving the real-time monitoring of various parameters such as temperature ,composition etc. from these units (hydrogenation and aromatic extraction). The parameters are collected through field-installed tags and must be interpretable by chemical technologists. The goal is to mitigate operational hazards and prevent production losses by ensuring a proactive response to deviations in operating conditions.

Solution

PI AF (Plant Information) serves as a real-time data storage and visualization platform (PI Vision), enabling chemical technologists to monitor the health of hydrogenation and aromatic units effectively. The system provides alerts in case any parameter deviates the designated operating envelope. This proactive approach ensures a swift and informed response to maintain safe and sustained operations, failure to which the plant's performance monitor ineffectiveness would lead to potential mid to long-term impacts on operations. Subsequently, the integration of PI in petrochemical plants is crucial for maintaining operational efficiency, preventing hazards, and securing the long-term viability of the plant.

The solution has potential to be replicated across petrochemical plants of Shell with scope of customization included.