Hydrocracker Feeds

Question How does this affect the amp load on the motor driver Well, the feet of head has gone down by about 10 percent, and the specific gravity has gone up by about 10 percent. Therefore, the horsepower or work per barrel of liquid pumped, remains constant. But the number of barrels has increased by 6000 bbl/day, or 35 percent. Then, the amp load on the motor driver would also increase by 35 percent. If I had not remembered this, prior to cooling the hydrocracker feed, the motor would have tripped off. As it was, I had the steam to the turbine increased. So as to decrease the motor amps to 60 percent of maximum, before cooling the gas oil. Omission of this detail, would have had embarrassing and possibly negative contractual consequences. 

Part or all of three FCC products heavier than gasoline can be recycled from the fractionator back to the reactor the light cycle oil which at Toledo is a prime hydrocracker feed, the heavy cycle oil which is usually recycled, and the bottoms or slurry oil, part of which must be recycled to return entrained catalyst to the unit. The program offers six recycle options. For any option, the user specifies five out of the following eight recycle variables ... 

Catalyst System-C incorporated Denitrification catalyst intended to lower Nitrogen in VGO (Hydrocracker Feed stock). The advantages over Catalyst System-B, if any, was not clear. Higher Distillate stability was expected but could not be substantiated. Distillate yield was comparable with that of Catalyst System-B. 

Three licensors, Foster Wheeler USA Corp, Kellogg Brown Root, Inc., and UOP LLC, offer flow diagrams and a discussion of their process in Hydrocarbon ProcessingP These process vendors cumulatively report over 110 commercial applications of this technology. Each licensor offers their process for application in lube processing or in the preparation of catalytic cracker or hydrocracker feed. All vendors also discuss the use of supercritical conditions for solvent recovery. This is discussed later under Solvent Recovery. ... 

COED Straight Run Feed 1st Pass 2nd Pass Hydrocrackate Feed Product... 

Pyrolysis Oil fuel oil, fuel oil 213 C plus blending, hydrocracker feed, carbon black production... 

The gas oil derived from Stage 2 processing has been tested in a variety of services and found to be of comparable thermal stability to typical refinery stocks. The gas oil has been used in hydrocracker feed, as a blending component for fuel oil, and other services. 

A Midwestern refinery had recently revamped the FCCU main fractionator. The top five trays, used to fractionate between naphtha and hydrocracker feed, were replaced with 8 ft of structured-type packing. The naphtha end-point specification was 420 F and the hydrocracker feed end-point spec was 800 F. The purpose of the revamp was to improve fractionation between naphtha and hydrocracker feed. 

Unfortunately, when the tower was commissioned after the revamp, fractionation was observed to be worse, not better, than before the revamp. To meet the naphtha end-point spec, 35% of the FCCU naphtha had to be under-cut into the hydrocracker feed product. 

What could be done to minimize the naphtha content of hydrocracker feed ... 

Sections 1, 2, 3, and 4 were now being used to fractionate between naphtha and hydrocracker feed. The loss in naphtha product to hydrocracker feed fell from 35% to 5%. The slurry oil pumparound draw temperature, while somewhat reduced, was still hot enough to maintain the fractionator heat balance. While this change did nothing to enhance top reflux distribution, it did bring all products back on spec without an FCCU shutdown. 

Kerosine, diesel fuel Aviation turbine fuel Gas oil, fuel oil Transformer oil FCC hydrocracker feed Lubricating oil Asphalt, pitch Wax... 

Vacuum gas oils, used as catalytic cracker or hydrocracker feeds, to remove sulfur, nitrogen, and metal impurities. 

Light Coker Gasoil (LCGO) LCGO may be used as hydrocracker feed or as FCC feed previous to hydrotreating. 

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