Results fluid catalytic cracking

Refinery Production. Refinery propylene is formed as a by-product of fluid catalytic cracking of gas oils and, to a far lesser extent, of thermal processes, eg, coking. The total amount of propylene produced depends on the mix of these processes and the specific refinery product slate. For example, in the United States, refiners have maximized gasoline production. This results in a higher level of propylene production than in Europe, where proportionally more heating oil is produced. 

In support of the power recovery expander market for fluid catalytic cracking units in refineries, some turboexpander manufacturers have an ongoing program to improve the solid particle erosion characteristics of the machine. Improved erosion characteristics will result in longer blade life, less downtime, and consequently greater profits for the users. 

The most important undesired metallic impurities are nickel and vanadium, present in porphyrinic structures that originate from plants and are predominantly found in the heavy residues. In addition, iron may be present due to corrosion in storage tanks. These metals deposit on catalysts and give rise to enhanced carbon deposition (nickel in particular). Vanadium has a deleterious effect on the lattice structure of zeolites used in fluid catalytic cracking. A host of other elements may also be present. Hydrodemetallization is strictly speaking not a catalytic process, because the metallic elements remain in the form of sulfides on the catalyst. Decomposition of the porphyrinic structures is a relatively rapid reaction and as a result it occurs mainly in the front end of the catalyst bed, and at the outside of the catalyst particles. 

Norco, Louisiana (Ref. 15) 7 (6 in buildings) A corrosion-induced propane leak in a fluid catalytic cracking unit resulted in an explosion that destroyed the control room. Six fatalities occurred in or near the control room the seventh was caused by a falling brick wall. 

A microscale Fluid Catalytic Cracking (FCC) simulation test is presented, which results in yields and product properties which correspond very well with commercial FCC results. 

Alumina-promoted fluid catalytic cracking catalysts, commercial viability, 414 Analysis of testing responses definition of sensitivity of result to given variable, 94 problems, 95... 

A significant application of FF on a commercial scale is the FF regenerator in fluid catalytic cracking processes. In Chapter 9, J. Chen, H. Cao, and T. Liu of Luoyang Petrochemical Engineering Corporation (LPEC) describe the development and design of four types of FF regenerators and the results of their commercial operation. More than 30 such units are in operation in China. 

The catalysts used in Fluid Catalytic Cracking (FCC) are reversibly deactivated by the deposition of coke. Results obtained in a laboratory scale entrained flow reactor with a hydrowax feedstock show that coke formation mainly takes place within a time frame of milliseconds. In the same time interval conversions of 30-50% are found. After this initial coke formation, only at higher catalyst-to-oil ratios some additional coke formation was observed. In order to model the whole process properly, the coke deposition and catalyst deactivation have to be divided in an initial process (typically within 0.15 s) and a process at a larger time scale. When the initial effects were excluded from the modeling, the measured data could be described satisfactory with a constant catalytic activity. 

Feedstocks to the coker generally consist of vacuum resids along with some slops (refinery or petrochemical waste streams) heavy FCC (fluid catalytic cracking) slurry oils, which contain unconverted hydrocarbons and traces of catalyst fines entrained from the reactor and asphalts. The coker is often the final disposition for many poor quality refinery process streams. As a result, the feedstock to the coker contains high levels of impurities. 

A deadly incident occurs in a fluid catalytic cracking unit during a startup after a turnaround. Superheated oil is allowed into a vessel that had accidentally accumrrlated water resulting in an explosion and fire in which six workers lost their lives. 

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