Sub-Product

The Pygas C₅⁺ cut, if left in its raw form, has little commercial value owing to its high reactivity and low stability. However, the stream contains many high-value components, such as Isoprene, Benzene, Toluene and Xylenes. Benzene is a key component in Pygas.

On a capacity basis, Pygas extraction accounts for approximately 36% of global Benzene. Extracting these components can be highly economical and typically requires Hydrotreating in a Pygas Hydrogenation Unit (PHU).

The stream can be treated in various ways, depending on the required product slate. Pygas Hydrotreating consists of three steps:

1. First stage Hydrotreating section to saturate mainly Di-olefins to Olefins;
2. Second stage Hydrotreating section to saturate the Olefins and De-sulfurize the Pygas;
3. Fractionation section to stabilize the Hydrotreated streams and to recover the C₆-C₈ heart cut for further processing for Aromatics extraction and the C9+ cut.