Ebullating Bed Units

The ebullated-bed unit consisted of a single reactor loaded with C0-M0/AI2O3 -type catalyst. The feedstock used was vacuum residue of Kuwait export crude diluted with about 10%-15% recycled gas oil (S = 5.2 wt% metals [V + Ni] = 110 ppm N = 4400ppm). Spent catalyst samples were collected from the equilibrium catalyst withdrawn from the reactor, which is a mixture of highly fouled and partially fouled catalysts. The properties of the heavy and light portions of the spent catalyst are presented in Table 10.2. The heavily fouled catalyst contained a substantially higher amount of vanadium (13.83 wt%) than the slightly fouled one (V = 4.37 wt%). Carbon content did not differ appreciably between the two types of spent catalyst particles. 

LC-Fining, as developed by ABB Lummus Crest, represents a branch of the HRI technology, which saw its first commercial operation come online in 1984 at BP, Texas City refinery in the United States. The BP LC-Fining unit was the first three-stage ebullated-bed unit. The meaning of LC is Lummus Corporation, the process developer company. 

A list of emrrent operating ebullated-bed units and some planned to be commissioned in the next years is given in Table 10.4. Operating conditions of ebullated-bed prcx esses (H-Oil and LC-Fining) are sununarized in Table 10.5. 

Current Operating and Planned Ebullated-Bed Units around the World... 

China Ebullated-bed units planned to be commissioned in the 16. Petro-Canada Edmonton, LC-fining next years 2009 50,000 liquids Oil smids... 

In the reactor of Figure 8.3, a stable fluidized bed is maintained by recirculation of the mixed fluid through the bed and a draft tube. An external pump sometimes is used instead of the built-in impeller shown. Such units were developed for the liquefaction of coal and are called ebullating beds.. 

Fixed bed heavy oil processing units which have a gradient of vanadium and nickel contamination from top to bottom in the reactor. Ebullated bed resid units with broad distribution of catalyst age and contaminant level. 

The H-Oil process is a high pressure, high temperature hydrocracking process, which uses an ebullated bed of catalyst to convert lower value heavy oils into upgraded higher value products. Deposit formation in the equipment downstream of the H-Oil reactor and high sediment accumulation in heavy fuel oil product streams are confining factors in current attempts to maximize H-Oil unit conversion. 

An accurate selection of the set of operating conditions ensures the best process performance. The main process variables (temperature, pressure, space velocity, and H2/oil ratio) are adjusted according to the specific HDT application. Table 13.3 shows typical operating conditions of various processes [59, 60]. Most of these processes are generally carried out in fixed-bed units, with the exception of ebullated-bed residue HCR. Naturally, the severity of the process increases with the heaviness of the feedstock. Distillate HDT is carried out at relatively mild conditions compared to residue HDT. HCR processes require more severe conditions than HDT and are much more demanding in terms of hydrogen supply. A brief discussion on the effect of these variables is presented later. 

In fixed-bed hydrocrackers designed to process VGO, residual oils in the feed can reduce catalyst cycle life if they contain even trace amounts of salts, asphaltenes, refractory carbon, trace metals (Fe, Ni, V), or particulate matter. As mentioned in Section 3.4.2, fixed-bed units designed to process residue remove metals and other contaminants with upstream guard beds or onstream catalyst replacement technology. In contrast, ebullated bed hydrocrackers can and do process significant amounts of residual oils. This is because fresh... 

The H-Coal process was an adaptation of the H-Oil process used in the petroleum industry to convert heavy oil residues to lighter fractions using a catalytic ebullated bed reactor.Research on the H-Coal process began in 1964 at Hydrocarbon Research, Inc. (HRI) on a bench-scale unit, and by 1973 the design of a 200- to 600-ton/day pilot plant was under way. Construction of the plant was completed in early 1980. Located adjacent to the Ashland Oil refinery in Cattletsburg, Kentucky, it operated succesfully from startup in May 1980 until shutdown in November 1982. 

Slurry-phase + ebullated-bed. HCAT slurry-phase technology can be integrated to improve the performance of existing ebullated-bed upgrading units as reported by Neste Oil (HTI, 2011). 

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