A hydrocracking

Typical feedstock composition, yields and product properties for a hydrocracking unit (to be continued). 

In an effort to obtain higher value products from SRC processes, a hydrocrackiag step was added to convert resid to distillate Hquids. The addition of a hydrocracker to the SRC-I process was called nonintegrated two-stage Hquefaction (NTSL). The NTSL process was essentially two separate processes ia series coal Hquefaction and resid upgrading. NTSL processes were iaefficient owiag to the inherent limitations of the SRC-I process and the high hydrocracker severities required. 

C. R. Cutier and R. B. Hawkins, "AppHcation of a Large Model Predictive Controller to a Hydrocracker Second Stage Reactor," Proceedings of... 

Toluene is dealkylated to benzene over a hydrogenation-dehydrogenation catalyst such as nickel. The hydrodealkylation is essentially a hydrocracking reaction favored at higher temperatures and pressures. The reaction occurs at approximately 700°C and 40 atmospheres. A high benzene yield of about 96% or more can be achieved ... 

HCO is the sidecut stream from the main column that boils between LCO and decanted oil (DO). HCO is often used as a pumparound stream to transfer heat to the fresh feed and/or to the debutanizer reboiier. HCO is recycled to extinction, withdrawn as a product and processed in a hydrocracker, or blended with the decant oil. 

MM. Internal decarburization/fissuring of piping in a hydrocracker unit after 235,000 hours of service. 

Commissioning of the Oryx GTL facility started in 2006 and production of the first GTL products was announced in February 2007.63 However, overproduction of a fine sediment as a result of catalyst attrition reduced throughput,64 and at the time of this writing sustained full-scale production had not yet been achieved. The syncrude resembles other LTFT syncrudes (Tables 18.2 and 18.8), and the refinery consists of a single conversion unit, namely, a hydrocracker (Figure 18.9). 

Hy-C Cracking A hydrocracking process. The catalyst is nickel/tungsten on alumina. Developed by Cities Service Research and Development Company and Hydrocarbon Research. 

Isocracking A hydrocracking process developed and licensed by Chevron Research Company. The catalyst is nickel or cobalt sulfide on an aluminosilicate. First commercialized in 1962 more than 45 units had been built by 1994. See also Isomax. 

LC-Fining [Lummus Cities refining] A hydrocracking process using an ebullated catalyst bed. Developed by Lummus Crest and Cities Service Research and Development Company since the 1960s, initially for upgrading bitumen from tar sands. Three units were operating in 1996. 

Lomax An outdated name for a hydrocracking process now offered under the name Unicracking. 

MRH (2) A hydrocracking process for difficult petroleum residues, i. e., those containing high levels of metals, sulfur, and nitrogen compounds. It uses catalytic hydrogenation in a slurry bed. Developed by the MW Kellogg Company. 

The acid component of a hydrocracking catalyst can be an amorphous oxide, e.g., a silica-alumina ora zeolite, eg., USY. This component usually serves as a support for the metal compound responsible for the hydrogenation function. The metal compound can be a noble metal, e.g., Pt or Pd, or a mixture of sulfides, e.g., of Ni/Mo, NiAV, or Co/Mo. The relative amounts of the respective compounds have to be thoroughly balanced to achieve an optimum performance. 

Figure 16.5 Impact of pretreating severity on the activity of a hydrocracking catalyst temperature required for conversion of a feed hydrotreated to (a) 40 ppm nitrogen, (b) 10ppm nitrogen.

New Brunswick, Canada Process Facility—A fire originated in the feed heater of a hydrocracker and resulted in one fatality and significant damage to a Hydrocracking Unit. 

Catalytic Dewaxing Also called CDW. A hydrocracking process for removing waxes (linear aliphatic hydrocarbons) from petroleum streams by converting them to lower molecular weight hydrocarbons. The catalyst is a synthetic mordenite. Developed by BP two units were operating in 1988. 

To produce the maximum yield of finished gasoline in a hydrocracker-reformer combination, the hydrocracker should be operated to give maximum liquid yields, followed by a modem low pressure catalytic reformer to give the desired octane improvement (6). More severe hydrocracker operation produces higher octane naphtha but leads to an increase in the production of butanes with reduced yields of finished... 

We can expect continuing growth of hydrocracking because it is able to satisfy both of these requirements. Pollutants are removed as ammonia and hydrogen sulfide. The technology is readily available (29) for recovering these materials for commercial use. Water requirements are moderate, and the self-contained nature of a hydrocracker makes it particularly attractive when close environmental control is required. 

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