Fluid catalytic cracker

IFP Process for 1-Butene from Ethylene. 1-Butene is widely used as a comonomer in the production of polyethylene, accounting for over 107,000 t in 1992 and 40% of the total comonomer used. About 60% of the 1-butene produced comes from steam cracking and fluid catalytic cracker effluents (10). This 1-butene is typically produced from by-product raffinate from methyl tert-huty ether production. The recovery of 1-butene from these streams is typically expensive and requires the use of large plants to be economical. Institut Francais du Petrole (IFP) has developed and patented the Alphabutol process which produces 1-butene by selectively dimerizing ethylene. 

P. K. Ladwig, T. R. Steffens, S. L. Laley, D. P. Leta, and R. D. Patel, "Resid Processing in Fluid Catalytic Crackers," Foster Wheeler Heavy Oils Conference, Orlando, Fla., June 7, 1993. 

The other significant industrial route to /-butyl alcohol is the acid cataly2ed hydration of isobutylene (24), a process no longer practiced in the United States. Raffinate 1, C-4 refinery streams containing isobutylene [115-11-7], / -butenes and saturated C-4s or C-4 fluid catalytic cracker (ECC) feedstocks (23)... 

The various sources of isobutylene are C streams from fluid catalytic crackers, olefin steam crackers, isobutane dehydrogenation units, and isobutylene produced by Arco as a coproduct with propylene oxide. Isobutylene concentrations (weight basis) are 12 to 15% from fluid catalytic crackers, 45% from olefin steam crackers, 45 to 55% from isobutane dehydrogenation, and high purity isobutylene coproduced with propylene oxide. The etherification unit should be designed for the specific feedstock that will be processed. 

Various design configurations for fluid catalytic crackers are illustrated in Figure 3. Their distinguishing features can be summarized as follows ... 

Figure 3. Various designs for fluid catalytic crackers.

MOI [Mobil olefin interconversion] A process for increasing the yield of propylene from steam crackers and fluid catalytic crackers, using a ZSM-type catalyst. Developed in 1998 by Mobil Technology. 

Of the many factors which influence product yields in a fluid catalytic cracker, the feed stock quality and the catalyst composition are of particular interest as they can be controlled only to a limited extent by the refiner. In the past decade there has been a trend towards using heavier feedstocks in the FCC-unit. This trend is expected to continue in the foreseeable future. It is therefore important to study how molecular types, characteristic not only of heavy petroleum oil but also of e.g. coal liquid, shale oil and biomass oil, respond to cracking over catalysts of different compositions. 

Regression-Based Planning Example of the Fluid Catalytic Cracker... 

Artificial-Neural-Network-Based Modeling Example of Fluid Catalytic Cracker 37... 

Arbel, A., Huang, Z., Rinard, I.H., Shinnar, R., and Sapre, A.V. (1995) Dynamics and control of fluid catalytic crackers 1. Modelling of the current generation of FCC s. Industrial Engineering Chemistry Research, 34, 1228. 

At the end of the 1970s Statoil cracked a North Sea atmospheric residue for the first time in M. W. Kellogg s circulating pilot nnit in Texas [1]. This pilot unit was qnite large, with a capacity of one barrel a day. The test in this pilot nnit was very snccess-ful and showed that North Sea atmospheric residnes were very suitable feedstocks for a residue fluid catalytic cracker, and that North Sea atmospheric residnes gave very promising prodnct yields. 

Some years later Statoil decided to start a project within catalytic cracking in order to learn more abont residue fluid catalytic cracking in general, and particnlarly abont catalysts suitable for this process. The project started as a prestudy for the residue fluid catalytic cracker unit (FCCU) that Statoil was planning to bnild at the Mongstad refinery in Norway. The intention was to crack North Sea atmospheric residue directly, without first using a vacuum gas distillation tower followed by cracking... 

The feeds used in all experiments presented in this paper are North Sea atmospheric residues originating from the atmospheric distillation tower at the Statoil Mongstad refinery in Norway. After the start-up of the residue fluid catalytic cracker at this refinery in 1989, the same feed has been used both in the commercial FCCU and in the ARCO pilot unit at Chalmers. Typical data for some North Sea atmospheric residue feeds used in the ARCO pilot unit are shown in Table 3.1. 

In a typical fluid catalytic cracker, catalyst particles are continuously circulated from one portion of the operation to another. Figure 9 shows a schematic flow diagram of a typical unit W. Hot gas oil feed (500 -700°F) is mixed with 1250 F catalyst at the base of the riser in which the oil and catalyst residence times (from a few seconds to 1 min.) and the ratio of catalyst to the amount of oil is controlled to obtain the desired level of conversion for the product slate demand. The products are then removed from the separator while the catalyst drops back into the stripper. In the stripper adsorbed liquid hydrocarbons are steam stripped from the catalyst particles before the catalyst particles are transferred to the regenerator. 

The hot oil to the kettle boiler is a circulating pumparound stream, from a fluid catalytic cracker fractionator, slurry-oil circuit. There is a fundamental difference between this sort of boiler and the utility plant boilers discussed previously. In the kettle boiler, the heating medium is inside, rather than outside, the tubes. To obtain the full capacity of... 

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