Coal liquefaction research, October 1, 1978-September 30, 1981. [Comparison between fixed bed and slurry type reactors]
Progress reports are presented for the following two areas: catalytic cracking studies with water-wet silica-alumina catalysts; and Fischer-Tropsch reactor studies where similarities and differences between fixed bed and slurry type reactors are investigated and further experiments conducted to measure mass transfer coefficients and reaction kinetics which are to be used in a model slurry reactor. The following are some of the conclusions. (1) The premise that the presence of liquid water might increase catalytic cracking activity was found to be invalid. It was demonstrated that cracking can occur at previously unobserved low temperatures (though at low conversions) and that an anomaly exists in that one of the catalysts tested shows an entirely different cracking behavior and probably follows a different cracking mechanism. (2) the diameter of a fixed-bed Fischer-Tropsch reactor critically affected the resistance of the reactor to plugging caused by the build up of carbonaceous or waxy deposits. Plugging was very likely due to local nonuniformity in the catalyst temperature. Decreasing the reactor diameter at a fixed gas space velocity, should improve temperature uniformity by decreasing the length of the thermal conduction path and increasing the extent of convective heat transfer from each catalyst particle. Suppression of plugging at higher H/sub 2//CO ratios is likely due to a reduction in the product average molecular weight and the reaction with hydrogen of carbon deposited via the Boudouard reaction. A slurry bed reactor with its much greater isothermicity can be expected to behave similarly to very small diameter fixed bed reactors and therefore have a higher tolerance of lower H/sub 2//CO ratio feed gas.
- Research Organization:
- Lawrence Berkeley Lab., CA (USA)
- DOE Contract Number:
- W-7405-ENG-48; FG22-78ET11432
- OSTI ID:
- 6051275
- Report Number(s):
- LBL-13238; ON: DE81030379
- Country of Publication:
- United States
- Language:
- English
Similar Records
Coal-liquefaction research. Semi annual progress report, October 1, 1980-March 30, 1981. [Slurry reactor vs fixed bed]
DEVELOPMENT OF ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS
Related Subjects
ALUMINIUM OXIDES
CATALYTIC EFFECTS
COMPARATIVE EVALUATIONS
COAL LIQUEFACTION
RESEARCH PROGRAMS
FISCHER-TROPSCH SYNTHESIS
CATALYSTS
CHEMICAL REACTORS
HEXADECANE
CRACKING
SILICA
CHEMICAL REACTION KINETICS
MASS TRANSFER
WATER
ZEOLITES
ALKANES
ALUMINIUM COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
HYDROCARBONS
HYDROGEN COMPOUNDS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
KINETICS
LIQUEFACTION
MATERIALS
MINERALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PYROLYSIS
REACTION KINETICS
SILICON COMPOUNDS
SILICON OXIDES
THERMOCHEMICAL PROCESSES
010405* - Coal
Lignite
& Peat- Hydrogenation & Liquefaction