Consequently, it is attractive to recover as much hydrocarbon feedstock, such as heavy vacuum gas oil (HVGO), as possible from the atmospheric residue (AR) that is routed to conversion units.
Shell Global Solutions’ deep-flash, high-vacuum technology has been developed through extensive research on mass transfer and separation equipment, and has also been supported by operating experience from numerous Shell and Shell-advised units over many years. This technology includes five key design features that can be tailored to meet a refiner’s specific revamp requirements. These are the:
- proprietary furnace coil design;
- Schoepentoeter* inlet device;
- wash-oil section design;
- insulated, low pressure drop draw-off trays; and
- direct contact condensation sections.
In this article, we profile two HVU revamp projects at European refineries. When scoping these projects, it became clear that both refiners had limited capital and a strong desire to minimise unit downtime, so Shell Global Solutions’ consultants, working with the refinery teams, elected to install only a selection of the key design features. This demonstrates the flexibility of the technology.