No. 2 Distillate Desulfurizer

Removes sulfur content from diesel P

44,000 BPD Capacity 

No. 2 DD is designed to process light and heavy gas oils and heavy naphtha from the Delayed
Coking Unit. The gas oil feeds are combined and filtered to remove coke fines before entering
the feed surge drum. Coker heavy naphtha is fed separately to the unit and is also filtered
before entering the naphtha feed surge drum. The gas oil stream is pumped by the unit charge
pump through the feed effluent exchangers. Prior to the exchangers recycle hydrogen is
injected into the gas oil stream. From the feed effluent exchangers the gasoil enters two
parallel reactor feed fuel gas fired furnaces. After the furnaces the gasoil stream is mixed with
the naphtha stream and the combined stream enters the reactors. The reactors have four beds
of NiMo catalyst with inter bed hydrogen quench for temperature control. Typical reactor
conditions are a pressure of 1120 psig and a reactor outlet temperature (EOR) of 790 deg. F.

The reactor product is cooled against incoming gasoil feed then air cooled prior to the reactor
effluent separator. In the separator the recycle hydrogen stream is separated from the liquids
and flows to the recycle gas amine contactor where a circulating MEA stream removes
hydrogen sulfide. After amine treating the recycle hydrogen stream is compressed by the motor
driven recycle compressors back to the feed section. The liquids are separated into oil and
water phases. The sour water is degassed before being routed to the sour water collection
system. The oil stream is routed to the low pressure flash drum where the flashed gas is sent to
the refinery fuel gas collection system for amine treating. Any further sour water is routed to
the sour water collection system and the oil stream is routed to the product stripper tower
where any remaining hydrogen sulfide and fuel gas is removed to the refinery fuel gas
collection system for amine treating. The twenty five tray stripper tower is reboiled by a fuel
gas fired furnace. Naphtha is produced as an overhead stream from the stripper and is routed
to Platformer feed storage. The gas oil product is routed to Area 1 for further fractionation into
naphtha, kerosene, diesel and gas oil.