The plant will convert the heavy feedstock into ultra-low sulfur diesel and other lighter hydrocarbons, including naphtha, and hydrogenated gasoil, depending on the operating mode.

This revamp project aims to increase the capacity of the HCM unit to 30 KBPD and to keep the flexibility of the HCM unit to achieve diesel production in a sustainable manner within the quality parameters required by customers and the refinery. The above implies evaluating the adequacy of all the existing HCM equipment (pumps, exchangers, and vessels), and control valves to operate at the increased capacity of 30 kBPD. Equipment found to be inadequate will be specified as new. The reactor R-2654 will also be specified as new.

Another objective of the conceptual engineering was to solve thermal, hydraulic, and mechanical issues that have been evidenced in the last year of operation or found during the development of Basic

Engineering - Technological Improvement of the HCM Plant - Phase I. These issues are related to, among other factors: insufficient feed preheating, operational instability of the amine system (T-2651), design limitations in hydrogen production (U-2600) and RGC compressor.

The project scope outside HCM battery limits (OSBL) includes other units such as Amine Units (New Unit, U-2870 and U-4860), Utilities Area and other interconnections as Pump House 2 and Blending Area. These OSBL items were analysed and modified or specified as new as necessary to support the main objective.

The main challenge of this project was to convert a hydrocracking unit to a dual-operation unit allowing it to operate as hydrocracking and hydrotreating depending on the settings of the plant and the load received.

The variety of loads anticipated by the end customer required flexibility in the operating capacity of the very complex plant, which represented a great challenge when designing and pre-selecting equipment that could meet all the anticipated conditions and scenarios. In addition to the above, taking into account that this project is the revamp of a plant in service, the project had to consider replacing the least number of equipment possible as well as a design that had the least impact on downtime.