Flow hydrocracker

Table IV. Effect of Bed Dilution with Fine Particles on Residence Time Distribution of Oil in a Bench-scale Reactor under Conditions of Trickle-flow Hydrocracking...

The HPC is a mild trickle flow hydrocracking process using a Shell proprietary catalyst and operating at typically 30-50 bar total pressure and at a temperature of about 300-350°C. The plant lay-out is very similar to that of a conventional gas oil hydrotreater. The HPC stage performs actually four functions ... 

Basic to establishing whether power recovery is even feasible, let alone economical, are considerations of the flowing-fluid capacity available, the differential pressure available for the power recovery, and corrosive or erosive properties of the fluid stream. A further important consideration in feasibihty and economics is the probable physical location, with respect to each other, of fluid source, power-production point, and final fluid destination. In general, the tendency has been to locate the power-recoveiy driver and its driven unit where dictated by the driven-unit requirement and pipe the power-recoveiy fluid to and away from the driver. While early installations were in noncorrosive, nonerosive services such as rich-hydrocarbon absorption oil, the trend has been to put units into mildly severe seiwices such as amine plants, hot-carbonate units, and hydrocracker letdown. 

Hydrodewaxing Selective hydrocracking of paraffins from oil fractions or products to prevent wax precipitation (negative influence on cold flow properties) ... 

MAK fining A petroleum refining process which combines MAK hydrocracking with a cold-flow improvement process. Developed by Nippon Ketjen and first licensed in 1998. 

Figure 16.4 Process flow diagrams for major hydrocracker designs.

Fixed- or packed-bed reactors refer to two-phase systems in which the reacting fluid flows through a tube filled with stationary catalyst particles or pellets (Smith, 1981). As in the case of ion-exchange and adsorption processes, fixed bed is the most frequently used operation for catalysis (Froment and Bischoff, 1990 Schmidt, 2005). Some examples in the chemical industry are steam reforming, the synthesis of sulfuric acid, ammonia, and methanol, and petroleum refining processes such as catalytic reforming, isomerization, and hydrocracking (Froment and Bischoff, 1990). 

Trickle-bed reactors usually consist of a fixed bed of catalyst particles, contacted by a gas liquid two-phase flow, with co-current downflow as the most common mode of operation. Such reactors are particularly important in the petroleum industry, where they are used primarily for hydrocracking, hydrodesulfurization, and hydrodenitrogenation other commercial applications are found in the petrochemical industry, involving mainly hydrogenation and oxidation of organic compounds. Two important quantities used to characterize a trickle-bed reactor are... 

Figure 2. Simplified hydrocracking two-stage process flow diagram...

Fig. 16. Schematic flow diagram showing solvent deasphalting (SDA) combined with residuum hydrocracking (Howell et al., 1985).

Figure 7. Flow diagram refining of SRC-II oil by hydrotreating and hydrocracking, case 4...

A flow diagram for a proposed shale oil refinery is shown in Figure 5. An FCC unit is used as the primary cracking process. This refinery produces high-octane gasoline and diesel fuel. Jet fuel also could be produced by severely hydrogenating a kerosene cut (10) from the whole-oil hydrotreater or by using a hydrocracker in place of the FCC. The... 

Although SRC-II was basically a thermal liquefaction process, it was most successful using bituminous coals with a high native pyrite content. Iron sulfides are well known to have catalytic properties for coal liquefaction. Recycling part of the ash-minerals-containing bottoms had two beneficial effects (1) it increased the pyrite concentration in the reactor feed, and (2) it increased the residence time for heavy components, thus giving them more time to hydrocrack to distillate products. A block flow diagram of the SRC-II process is shown in Fig. 19.19. 

The trickle-bed reactor can be operated as a partially or completely vapor-phase reactor. It minimizes the energy costs associated with reactant vaporization. Mixed flow conditions at the catalyst surface exist in hydrocracking reactions, hydrogenation of crotonaldehyde and isomerization of cyclopropane. When the temperature rise in a trickle-bed reactor is significant (e.g., hydrodesulfurization and hydrocracking reactions), it can be conveniently controlled by the addition... 

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