Phase‐equilibrium fractionation of continuous distributions

McCoy, Benjamin J.; Sterling, W. Jerome

doi:10.1002/aic.690460409

Cited by 5 publications

(2 citation statements)

References 17 publications

(11 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It should be more consistent with the underlying chemistry of thermolytic bond cleavage, recombination reactions, and volatilization of low MW products. Such models are based on a continuous reaction and species spectra, , which are characterized by MW and functional groups. Similar models are used to describe pyrolysis of synthetic polymers .…”

Section: Discussionmentioning

confidence: 99%

Biomass Pyrolysis in a Fluidized Bed Reactor. Part 2: Experimental Validation of Model Results

Wang

Kersten

Prins

et al. 2005

Ind. Eng. Chem. Res.

185

164

View full text Add to dashboard Cite

Various types of cylindrical biomass particles (pine, beech, bamboo, demolition wood) have been pyrolyzed in a batch-wise operated fluid bed laboratory setup. Conversion times, product yields, and product compositions were measured as a function of the particle size (0.7-17 mm), the vapor's residence time (0.25-6 s), the position of the biomass particles in the bed (dense bed or splash zone), and the fluid bed temperature (250-800 °C). For pyrolysis temperatures between 450 and 550 °C, the bio-oil yield appeared to be maximal (in this work: about 65 wt %), while the water content of the bio-oil is minimal. The position of the biomass particles in the fluid bed, either in the dense bed or in the splash zone, does not affect the conversion time and product yields to a large extent during pyrolysis at 500 °C. In the small fluid bed used for this work, with a char hold-up of up to 5 vol % (or 0.7 wt %), the residence time of the pyrolysis vapors is not that critical. At typical fast pyrolysis temperatures of around 500 °C, it appeared sufficient to keep this residence time below 5 s to prevent significant secondary cracking of the produced vapors to noncondensable gas. Up to a diameter of 17 mm, the particle size has only a minor effect on the total liquid yield. However, for particles larger than 3 mm, the water content of the produced bio-oil increases significantly. The experimental results are further compared with predictions from a one-dimensional (1D) and a two-dimensional (2D) single-particle pyrolysis model. Such models appeared to have a limited predictive power due to large uncertainties in the kinetics and selectivity of the biomass decomposition. Moreover, the product quality cannot be predicted at all.

show abstract

Section: Discussionmentioning

confidence: 99%

Biomass Pyrolysis in a Fluidized Bed Reactor. Part 2: Experimental Validation of Model Results

Wang

Kersten

Prins

et al. 2005

Ind. Eng. Chem. Res.

185

164

View full text Add to dashboard Cite

show abstract

“…More recently, McCoy and Madras 2001 showed that the discrete and continuous approaches lead to equivalent results for polymerization and depolymerization, and further that the discrete approach can be considered a special case of the continuous approach. Equilibrium thermodynamics of continuously distributed systems, based on the fundamental concept of the distribution of molecular properties, has advantages relative to a discrete approach for complex Ž systems Gualtieri et al, 1982;Salacuse and Stell, 1982;Briano and Glandt, 1983;Ratzsch and Kehlen, 1983;Cotterman et al, 1985;Evans et al, 1998;Choi and Bae, 1999;McCoy . and Sterling, 2000 .…”

Section: Introductionmentioning

confidence: 99%

Distribution kinetics of thermolytic macromolecular reactions

Sterling

McCoy

2001

AIChE Journal

Self Cite

View full text Add to dashboard Cite

Essential elements of thermolytic reaction kinetics for distributions of polymers are re®iewed. Bond scission, occurring randomly along a chain backbone or at the chain end, is the major reaction process in polymer thermolysis. Underlying this bond scission are free radical mechanisms, including initiation and termination, hydrogen abstraction, and beta scission. Population-balance equations for the molecular-weight distributions of macromolecules or their radicals describe the dynamics of the reactions. The go®erning integrodifferential equations for continuous distributions can be sol®ed by moment methods, similarity techniques, other analytical procedures, or numerical methods. The approach has been applied to analytical thermolysis and pyrolysis, polymer degradation for stability characterization or plastics recycling, and coal thermolysis to produce fuels and feedstocks. Experiments ha®e demonstrated the usefulness of the continuous distribution kinetics approach for polymer thermolysis with additi®es, including hydrogen donors, peroxides, and other polymers. Molecular-weight distributions and their moments can be measured by size exclusion chromatography. Experimental data can be interpreted by e®aluating rate parameters, which may be composites of rate coefficients for elementary steps in complex reaction mechanisms.

show abstract

Evaluation of different methodologies to determine the n-paraffin distribution of petroleum fractions

Espada

Fernández

Velasco

et al. 2013

Fuel

View full text Add to dashboard Cite

Phase‐equilibrium fractionation of continuous distributions

Abstract: Fractionation of continuously distributed homologous mixtures is described in terms

Cited by 5 publications

References 17 publications

Biomass Pyrolysis in a Fluidized Bed Reactor. Part 2: Experimental Validation of Model Results

Biomass Pyrolysis in a Fluidized Bed Reactor. Part 2: Experimental Validation of Model Results

Distribution kinetics of thermolytic macromolecular reactions

Evaluation of different methodologies to determine the n-paraffin distribution of petroleum fractions

Contact Info

Product

Resources

About