Fluidized bed pilot

The effect of ZSM-5 as an octane additive to a cracking catalyst was studied in both a small fixed-bed reactor and a fluidized-bed pilot plant. Analyses of the products of these tests were used to determine the reaction chemistry. It was found that by maximizing the ratio of isomerization activity to hydrogen transfer activity, gasoline octane was increased with a minimum of yield loss. This could be accomplished by increasing the silica-to-alumina ratio of the additive zeolite. 

Van Hook, J., and Robertson, A. Circulating Pressurized Fluidized Bed Pilot Plant, in Circulating Fluidized Bed Technology IV (Amos A. Avidan, ed.), pp. 278-283. Somerset, Pennsylvania (1993). 

Incine- ration system IHI Co. Ltd. Single fluidized bed Pilot plant 30 t/d Incinera- tion/Steam... 

Gasification of Oak Sawdust, Mesquite, Corn Stover, and Cotton Gin Trash in a Countercurrent Fluidized Bed Pilot Reactor... 

Koppatz, S., Schmid, J.C., Pfeifer, C. and Hofbauer, H. (2012) The effect of bed particle inventories with different particle sizes in a dual fluidized bed pilot plant for biomass steam gasification. Industrial Engineering Chemistry Research, 51, 10492-10502. 

A medium heat (11.2 MJ/m (300 Btu/ft )) gas for iadustrial appHcation has been produced at Westiaghouse Electric s pilot plant ia Waltz Mill, Pennsylvania (50), where lignite is gasified ia a pressurized fluidized bed which uses oxygen and steam. 

The CO2 Acceptor process, also developed under AGA/DOE sponsorship, by the ConsoHdation Coal Co., uses steam to gasify lignitic coal. Heat is supphed by the exothermic reaction between CO2 and calciaed dolomite [17069-72-6]. The dolomite is calciaed ia a separate fluidized bed. This process operates ia a 40 t/d pilot plant, but there are no plans for commercialization as of this writing. 

Dry dense medium (pneumatic fluidized-bed) separation has been used, but has not received wide attention by the industry. An area of promise for future development is the use of magnetically stabilized dense medium beds by using ferro or magnetic fluids (2,10). Laboratory and pilot-scale units such as Magstream are available. In this unit, material is fed into a rotating column of water-based magnetic fluid. Particles experience centtifugal forces and... 

Distributors in industrial units typically have large numbers of injection points of quite diverse design characteristics, some of which are depicted in Eigure 16 for fluidized-bed appHcations. Flow variations through these parallel paths can lead to poor flow distributions within a reactor, thus reducing product yields and selectivity. In some circumstances, undesirable side products can foul portions of the distributor and further upset flow patterns. Where this is important, or where the possibiHties and consequences are insufficiently understood and independent means caimot be employed to assure adequate distribution, the pilot plant must be sized to accommodate such a distributor. Spacing should be comparable to those distributors that are anticipated to be... 

Fig. 3. Pilot-plant fluidized-bed denitiatoi for denitration of U02(N0 )2 bHjO where UNH = utanyl nitrate liexahydrate (40),...

Sasol uses both fixed-bed reactors and transported fluidized-bed reactors to convert synthesis gas to hydrocarbons. The multitubular, water-cooled fixed-bed reactors were designed by Lurgi and Ruhrchemie, whereas the newer fluidized-bed reactors scaled up from a pilot unit by Kellogg are now known as Sasol Synthol reactors. The two reactor types use different iron-based catalysts and give different product distributions. 

Process development on fluidized-bed pyrolysis was also carried out by the ConsoHdation Coal Co., culminating in operation of a 32 t/d pilot plant (35). The CONSOL pyrolysis process incorporated a novel stirred carbonizer as the pyrolysis reactor, which made operation of the system feasible even using strongly agglomerating eastern U.S. biturninous coals. This allowed the process to bypass the normal pre-oxidation step that is often used with caking coals, and resulted in a nearly 50% increase in tar yield. Use of a sweep gas to rapidly remove volatiles from the pyrolysis reactor gave overall tar yields of nearly 25% for a coal that had Eischer assay tar yields of only 15%. 

There are many uses of fluidized beds. A number of applications have become commercial successes others are in the pilot-plant stage, and others in bench-scale stage. Generally, the fluidized bed is used for gas-solids contac ting however, in some instances the presence of the gas or sohd is used only to provide a fluidized bed to accomplish the end result. Uses or special (maracteristics follow ... 

Yang, W. C., Margaritis, P. J., and Keaims, D. L., Simulation and Modeling of Startup and Shutdown in a Pilot-Scale Recirculating Fluidized Bed Coal Devolatilizer, AIChE Symp. Ser., 74(176) 87 (1978)... 

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