a linear low density polyethylene (lldpe) production process, including two- fuidized bed reactors in series (fbrs) and other process equipment, was completely simulated by aspen polymer plus software. fluidized bed reactors were considered as continuous stirred tank reactors (cstr consisted of polymer and gas phases). poly-srk and nrtl-rk equations of state were used to describe polymer and no...

A catalyst and sorbent is disclosed which comprises pellets with an absorbent core and a protective shell with a catalyst in the shell. Such material is especially well suited for steam reforming of hydrocarbons to produce hydrogen since a reforming catalyst can be incorporated in the shell and a sorbent for the by-product carbon dioxide can be used for the core. It is also well suited for prod...

A fluidized bed reactor with ultraviolet lamp and TiO2/silica photo-catalyst prepared in our laboratory was used as a photo-reactor to degrade toluene in a simulated toluene-air mixture. The effects of operating parameters including initial toluene concentration, superficial gas velocity, ultraviolet light intensity and catalyst bed height on degradation rate of toluene have been investigated i...

The Catofin propane process is an emerging industrial process for propylene production through dehydrogenation of propane. It is composed of multiple adiabatic fixed-bed reactors which undergo cyclic operations where propane dehydrogenation and catalyst regeneration alternate over roughly ten minute period for each. One of the major concerns in the operation of the Catofin process is maintainin...

Frequently the activity of fresh catalyst changes with time in use. The decrease or increases of the catalyst activity with time during the course of reaction forces the system to an unsteady state operation ([1], [2], [3], [4] and [5]). One of these catalysts is the copper/zinc oxide catalyst, which is industrially used for methanol production. The activity of copper/zinc oxide catalyst declin...

Gasification of pyrolysis oil was studied in a fluidized bed over a wide temperature range (523-914 °C) with and without the use of nickel-based catalysts. Noncatalytically, a typical fuel gas was produced. Both a special designed fluid bed catalyst and a crushed commercial fixed bed catalyst showed an initial activity for syngas (H2 and CO) production at T >700 °C. However, these catalysts los...

The present work describes a reactor that allows in situ measurements of spatially resolved kinetic data in heterogeneous catalysis. The reactor design allows measurements up to temperatures of 1300 degrees C and 45 bar pressure, i.e., conditions of industrial relevance. The reactor involves reactants flowing through a solid catalyst bed containing a sampling capillary with a side sampling orif...

Since its discovery in the 1920s, the Fischer-Tropsch Synthesis (FTS) has undergone periods of rapid development and periods of inaction. Within ten years of the discovery, German companies were building commercial plants. The construction of these plants stopped about 1940 but existing plants continued to operate during WWII. Two types of reactors were used in the German commercial plants: the...

A large number of chemical, bio-chemical and pollution-control processes use heterogeneous fixed-bed reactors. The use of finite hollow cylindrical catalyst pellets can enhance conversion levels in such reactors. The absence of the pellet core can significantly lower the diffusional resistance associated with the solid phase. This leads to a better utilization of the catalytic material, which i...