Nov 25 2021
3 min read
A Crude-to-Chemicals (CTC) conversion block maximizes Heavy Naphtha (HN) production for the aromatics block (figure below) of a petrochemical complex.
Beside aromatics ring generation (Aromizing™ process), the ParamaX® suite brings together the core technologies for the production and transformation of aromatics.
Synergies between the conversion and the olefins blocks contribute to optimizing chemical production in a CTC complex. Recovery of aromatic molecules present in various streams such as Pyrolysis gasoline or aromatics-rich cut from fluid catalytic cracking shall be ensured while aromatics block co-product shall be properly harnessed as well, such a light ends and paraffinic raffinate return to olefins block.
The main entry point to the aromatics block is typically a reforming technology dedicated to the production of aromatics from heavy naphtha. It is the first step to high-purity paraxylene (PX), key intermediate in the value chain in the manufacture of the polyethylene terephthalate (PET) and fiber-consuming products.
Aromizing™ is Axens technology to reform heavy naphtha into aromatics employing continuous catalyst regeneration. This technology utilizes the Symphony™ catalyst system to maximize aromatics rings production while retaining operability and reliability. The aromatics block incorporates a tailor-made arrangement of four blocks dedicated to selective production of a wide range of aromatics that also include metaxylene, orthoxylene, benzene and toluene.
The benzene and toluene cut from the Aromizing or steam cracker Pygas contains non-aromatics that requires separation. Morphylane extractive distillation technology achieves benzene product purity target and recover non-aromatics in a liquid raffinate, which can be routed to the olefins block. After appropriate treatment FCC/HS-FCC™ aromatics-rich cut can be routed to a Sulfolane liquid-liquid extraction, which is adapted to recover aromatics from this larger boiling range cut.
The Aromatics rearrangement block converts toluene and C9+ aromatics cuts in order to direct and increase production of the desired aromatics, using several technologies of toluene alkylation (EMTAM℠) and disproportionation (PxMax℠) and heavy aromatics transalkylation (TransPlus℠).
C8 aromatic cuts are processed in the “xylenes loop” where paraxylene is purified and other xylenes converted to paraxylene. Eluxyl® is a molecular sieve-based technology enabling highest paraxylene purity and recovery. Xylenes isomerization technologies complements this block: XyMax℠ (EB Dealkylating Xylenes Isomerization), Oparis® (EB Reforming Xylenes Isomerization) and LPI℠ (Liquid Phase Xylenes Isomerization).
Moreover, Axens has established itself as environmental first movers by
incorporating a sustainable approach throughout its suite of licensed technologies. Axens ParamaX® suite is no exception. Repeated advances in design have led to an extraordinary reduction in energy consumption and the current third generation energy efficient (3GEE) Paramax design achieves the lowest paraxylene cost of production on the market.