Flexible process design and low capital cost lead to numerous opportunities to revamp older units.
Hydrofluoric Acid: HF alkylation units can be converted to ExSact by replacing the reaction section with two fixed beds. The separation train is retained and the process operates at the same isobutane recycle rate (I/O) as the original unit. The revamp yields savings of about 50% over a new grassroots unit and eliminates hydroxides, spent acid, and solid waste. more…
Catalytic Polymerization and Dimerization: Cat-poly and olefin dimerization units are particularly well suited for retrofit, since the existing reactors can be used with only minor modifications. A de-isobutanizer is added to the separation train. Capital investment is minimal. more…
Sulfuric Acid: Sulfuric acid-based units can be revamped by replacing the reactors with new fixed bed reactors, similar to HF alkylation units. Increased octane and lower operating costs are obtained. Logistical and safety issues associated with storage and transportation of spent acid are eliminated.
The ExSact process offers considerable advantages over olefin dimerization and indirect alkylation (dimerization followed by hydrogenation). It offers a 10 to 12-point MON advantage over the dimerization product, and double the production capacity for a given amount of olefin. This leads to a tremendous gain in octane-barrels.
