A test of the parallel reaction model using kinetic measurements on hydrous pyrolysis residues

Burnham, Alan K.; Schmidt, Birthe J.; Braun, Róbert

doi:10.1016/0146-6380(95)00069-0

Cited by 61 publications

(30 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Above all, the w parameter presents a correlation with the mean activation energy as high as 0.72. To de-correlate the parameters, it was tried to fit simultaneously sets of data taken at different heating rates [27,28]. In the regression code, a function, such as that reported in Equation (6), was created for each set of data, fixing the heating rate to the proper value.…”

Section: Resultsmentioning

confidence: 99%

Double Distribution Activation Energy Model as Suitable Tool in Explaining Biomass and Coal Pyrolysis Behavior

et al. 2015

View full text Add to dashboard Cite

Understanding and modeling of coal and biomass pyrolysis assume particular importance being the first step occurring in both gasification and combustion processes. The complex chemical reaction network occurring in this step leads to a necessary effort in developing a suitable model framework capable of grasping the physics of the phenomenon and allowing a deeper comprehension of the sequence of events. The aim of this work is to show how the intrinsic flexibility of a model based on a double distribution of the activation energy is able to properly describe the two separate steps of primary and secondary pyrolysis, which characterize the thermochemical processing of most of the energetic materials. The model performance was tested by fitting the kinetic parameters from experimental data obtained by thermogravimetric analysis of two materials, which represent very different classes of energy source: a microalgae biomass and a sub-bituminous coal. The model reproduces with high accuracy the pyrolysis behavior of both the materials and adds important information about the relative occurring of the two pyrolysis steps.

show abstract

Section: Resultsmentioning

confidence: 99%

Double Distribution Activation Energy Model as Suitable Tool in Explaining Biomass and Coal Pyrolysis Behavior

et al. 2015

View full text Add to dashboard Cite

show abstract

“…When conducted under controlled timetemperature conditions at different heating rates, measured hydrocarbon formation rate versus temperature curves provide reliable input data for the calculation of kinetic parameters which, in turn, allow to extrapolate from laboratory to geological heating rates which are ten orders of magnitude lower (Hanaba, Jüntgen & Peters, 1968;Philippi, 1965;Tissot & Espitalie, 1975). The reliability of the resulting predictions is directly related to the quality of the laboratory work (Burnham, Braun, & Gregg, 1987;Burnham, Schmidt, & Braun, 1995;, 1998.…”

Section: Introductionmentioning

confidence: 99%

Prediction of petroleum formation: the influence of laboratory heating rates on kinetic parameters and geological extrapolations

Schenk

Dieckmann

2004

Marine and Petroleum Geology

View full text Add to dashboard Cite

“…This difference suggests that ODP Mound fluids have attained higher levels of thermal stress. The degradation of straight chain hydrocarbons that constitute petroleum is generally viewed as a kinetically controlled process, where time and temperature are interchangeable variables ( BRAUN and ROTHMAN, 1975;BURNHAM et al, 1995;HUNT, 1996;TISSOT and WELTE, 1984;WAPLES, 1984). Thus, higher C 1 /(C 2 +C 3 ) ratios at the ODP Mound relative to Dead Dog indicate a more mature hydrocarbon suite that, in turn, reflects higher subsurface temperatures and/or longer subsurface residence times for circulating fluids.…”

Section: Kinetic Constraintsmentioning

confidence: 99%

Geochemistry of low-molecular weight hydrocarbons in hydrothermal fluids from Middle Valley, northern Juan de Fuca Ridge

Cruse

Seewald

2006

Geochimica et Cosmochimica Acta

108

View full text Add to dashboard Cite

Hydrothermal vent fluids from Middle Valley, a sediment-covered mid-ocean ridge on the northern Juan de Fuca Ridge, were sampled in July, 2000. Eight different vents with exit temperatures of 186 to 281°C were sampled from two areas of venting: the Dead Dog and ODP Mound fields. Fluids from the Dead Dog field are characterized by higher concentrations of ΣNH 3 and organic compounds (C 1 -C 4 alkanes, ethene, propene, benzene and toluene) compared with fluids from the ODP Mound field. The ODP Mound fluids, however, are characterized by higher C 1 /(C 2 +C 3 ) and benzene:toluene ratios than those from the Dead Dog field. The aqueous organic compounds in these fluids have been derived from both bacterial processes (methanogenesis in low-temperature regions during recharge) as well as from thermogenic processes in higher-temperature portions of the subsurface reaction zone. As the sediments undergo hydrothermal alteration, carbon dioxide and hydrocarbons are released to solution as organic matter degrades via a stepwise oxidation process. Compositional and isotopic differences in the aqueous hydrocarbons indicate that maximum subsurface temperatures at the ODP Mound are greater than those at the Dead Dog field. Maximum subsurface temperatures were calculated assuming that thermodynamic equilibrium is attained between alkenes and alkanes, benzene and toluene, and carbon dioxide and methane. The calculated temperatures for alkene-alkane equilibrium are consistent with differences in the dissolved Cl concentrations in fluids from the two fields, and indicate that subsurface temperatures at the ODP Mound are hotter than those at the Dead Dog field. Temperatures calculated assuming benzene-toluene equilibrium and carbon dioxide-methane equilibrium are similar to observed exit temperatures, and do not record the hottest subsurface conditions. The difference in subsurface temperatures estimated using organic geochemical thermometers reflects subsurface cooling processes via mixing of a hot, low-salinity vapor with a cooler, seawater salinity fluid. Because of the disparate temperature dependence of alkene-alkane and benzene-toluene equilibria, the mixed fluid records both the high and low temperature equilibrium conditions. These calculations indicate that vapor-rich fluids are presently being formed in the crust beneath the ODP Mound, yet do not reach the surface due to mixing with the lower-temperature fluids.2

show abstract

A test of the parallel reaction model using kinetic measurements on hydrous pyrolysis residues

Cited by 61 publications

References 11 publications

Double Distribution Activation Energy Model as Suitable Tool in Explaining Biomass and Coal Pyrolysis Behavior

Double Distribution Activation Energy Model as Suitable Tool in Explaining Biomass and Coal Pyrolysis Behavior

Prediction of petroleum formation: the influence of laboratory heating rates on kinetic parameters and geological extrapolations

Geochemistry of low-molecular weight hydrocarbons in hydrothermal fluids from Middle Valley, northern Juan de Fuca Ridge

Contact Info

Product

Resources

About