High-pressure pyrolysis and oxidation of DME and DME/CH4

Hamid Hashemi*, Jakob M. Christensen, Peter Glarborg

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

The pyrolysis and oxidation of dimethyl ether (DME) and its mixture with methane were investigated at high pressure (50 and 100 bar) and intermediate temperature (450–900 K). Mixtures highly diluted in nitrogen with different fuel–air equivalence ratios (Φ=∞, 20, 1, 0.06) were studied in a laminar flow reactor. At 50 bar, the DME pyrolysis started at 825 K and the major products were CH4, CH2O, and CO. For the DME oxidation at 50 bar, the onset temperature of reaction was 525 K, independent of fuel–air equivalence ratio. The DME oxidation was characterized by a negative temperature coefficient (NTC) zone which was found sensitive to changes in the mixture stoichiometry but always occurring at temperatures of 575–625 K. The oxidation of methane doped by DME was studied in the flow reactor at 100 bar. The fuel–air equivalence ratio (Φ) was varied from 0.06 to 20, and the DME to CH4 ratio changed over 1.8–3.6%. Addition of DME had a considerable promoting effect on methane ignition as the onset of reaction shifted to lower temperatures by 25–150 K. A detailed chemical kinetic model was developed by adding a DME reaction subset to a model developed in previous high-pressure work. The model was evaluated against the present data as well as data from literature. Additional work is required to reconcile experimental and theoretical work on reactions on the CH3OCH2OO PES with ignition delay measurements in the NTC region for DME.
Original languageEnglish
JournalCombustion and Flame
Volume205
Pages (from-to)80-92
ISSN0010-2180
DOIs
Publication statusPublished - 2019

Keywords

  • Dimethyl ether (DME)
  • Methane
  • Oxidation
  • High pressure
  • Reaction mechanism
  • F
  • Intermediate temperatures

Cite this

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title = "High-pressure pyrolysis and oxidation of DME and DME/CH4",
abstract = "The pyrolysis and oxidation of dimethyl ether (DME) and its mixture with methane were investigated at high pressure (50 and 100 bar) and intermediate temperature (450–900 K). Mixtures highly diluted in nitrogen with different fuel–air equivalence ratios (Φ=∞, 20, 1, 0.06) were studied in a laminar flow reactor. At 50 bar, the DME pyrolysis started at 825 K and the major products were CH4, CH2O, and CO. For the DME oxidation at 50 bar, the onset temperature of reaction was 525 K, independent of fuel–air equivalence ratio. The DME oxidation was characterized by a negative temperature coefficient (NTC) zone which was found sensitive to changes in the mixture stoichiometry but always occurring at temperatures of 575–625 K. The oxidation of methane doped by DME was studied in the flow reactor at 100 bar. The fuel–air equivalence ratio (Φ) was varied from 0.06 to 20, and the DME to CH4 ratio changed over 1.8–3.6{\%}. Addition of DME had a considerable promoting effect on methane ignition as the onset of reaction shifted to lower temperatures by 25–150 K. A detailed chemical kinetic model was developed by adding a DME reaction subset to a model developed in previous high-pressure work. The model was evaluated against the present data as well as data from literature. Additional work is required to reconcile experimental and theoretical work on reactions on the CH3OCH2OO PES with ignition delay measurements in the NTC region for DME.",
keywords = "Dimethyl ether (DME), Methane, Oxidation, High pressure, Reaction mechanism, F, Intermediate temperatures",
author = "Hamid Hashemi and Christensen, {Jakob M.} and Peter Glarborg",
year = "2019",
doi = "10.1016/j.combustflame.2019.03.028",
language = "English",
volume = "205",
pages = "80--92",
journal = "Combustion and Flame",
issn = "0010-2180",
publisher = "Elsevier",

}

High-pressure pyrolysis and oxidation of DME and DME/CH4. / Hashemi, Hamid; Christensen, Jakob M.; Glarborg, Peter.

In: Combustion and Flame, Vol. 205, 2019, p. 80-92.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - High-pressure pyrolysis and oxidation of DME and DME/CH4

AU - Hashemi, Hamid

AU - Christensen, Jakob M.

AU - Glarborg, Peter

PY - 2019

Y1 - 2019

N2 - The pyrolysis and oxidation of dimethyl ether (DME) and its mixture with methane were investigated at high pressure (50 and 100 bar) and intermediate temperature (450–900 K). Mixtures highly diluted in nitrogen with different fuel–air equivalence ratios (Φ=∞, 20, 1, 0.06) were studied in a laminar flow reactor. At 50 bar, the DME pyrolysis started at 825 K and the major products were CH4, CH2O, and CO. For the DME oxidation at 50 bar, the onset temperature of reaction was 525 K, independent of fuel–air equivalence ratio. The DME oxidation was characterized by a negative temperature coefficient (NTC) zone which was found sensitive to changes in the mixture stoichiometry but always occurring at temperatures of 575–625 K. The oxidation of methane doped by DME was studied in the flow reactor at 100 bar. The fuel–air equivalence ratio (Φ) was varied from 0.06 to 20, and the DME to CH4 ratio changed over 1.8–3.6%. Addition of DME had a considerable promoting effect on methane ignition as the onset of reaction shifted to lower temperatures by 25–150 K. A detailed chemical kinetic model was developed by adding a DME reaction subset to a model developed in previous high-pressure work. The model was evaluated against the present data as well as data from literature. Additional work is required to reconcile experimental and theoretical work on reactions on the CH3OCH2OO PES with ignition delay measurements in the NTC region for DME.

AB - The pyrolysis and oxidation of dimethyl ether (DME) and its mixture with methane were investigated at high pressure (50 and 100 bar) and intermediate temperature (450–900 K). Mixtures highly diluted in nitrogen with different fuel–air equivalence ratios (Φ=∞, 20, 1, 0.06) were studied in a laminar flow reactor. At 50 bar, the DME pyrolysis started at 825 K and the major products were CH4, CH2O, and CO. For the DME oxidation at 50 bar, the onset temperature of reaction was 525 K, independent of fuel–air equivalence ratio. The DME oxidation was characterized by a negative temperature coefficient (NTC) zone which was found sensitive to changes in the mixture stoichiometry but always occurring at temperatures of 575–625 K. The oxidation of methane doped by DME was studied in the flow reactor at 100 bar. The fuel–air equivalence ratio (Φ) was varied from 0.06 to 20, and the DME to CH4 ratio changed over 1.8–3.6%. Addition of DME had a considerable promoting effect on methane ignition as the onset of reaction shifted to lower temperatures by 25–150 K. A detailed chemical kinetic model was developed by adding a DME reaction subset to a model developed in previous high-pressure work. The model was evaluated against the present data as well as data from literature. Additional work is required to reconcile experimental and theoretical work on reactions on the CH3OCH2OO PES with ignition delay measurements in the NTC region for DME.

KW - Dimethyl ether (DME)

KW - Methane

KW - Oxidation

KW - High pressure

KW - Reaction mechanism

KW - F

KW - Intermediate temperatures

U2 - 10.1016/j.combustflame.2019.03.028

DO - 10.1016/j.combustflame.2019.03.028

M3 - Journal article

VL - 205

SP - 80

EP - 92

JO - Combustion and Flame

JF - Combustion and Flame

SN - 0010-2180

ER -