Teléfono:
Email: juanmcd@unizar.es
Address: Office 41.020. C/Mariano Esquillor s/n, Edificio I+D+i, I3A, Zaragoza, España
ABOUT ME h5>
Research Interests
Chemical processes, combustion, kinetic modeling, sulfur chemistry, biomass, pellets, PAH. My latest work is related to experimental and kinetic modeling of gas-phase chemistry. I am familiar with laboratory reactors (atmospheric and high pressure), some experience with catalysts gained through my Erasmus in Denmark doing the Master Thesis, some knowledge about PAH formation from biomass in a stay in Lisbon at IST and several hours modeling with Chemkin-PRO.
PUBLICATIONS h5>
2017
Colom-Díaz, Juan Manuel; Alzueta, María U; Fernandes, Ulisses; Costa, Mário
Emissions of polycyclic aromatic hydrocarbons during biomass combustion in a drop tube furnace Artículo de revista
En: Fuel, vol. 207, pp. 790–800, 2017, ISSN: 00162361.
@article{Colom-Diaz2017,
title = {Emissions of polycyclic aromatic hydrocarbons during biomass combustion in a drop tube furnace},
author = {Juan Manuel Colom-Díaz and María U Alzueta and Ulisses Fernandes and Mário Costa},
doi = {10.1016/j.fuel.2017.06.084},
issn = {00162361},
year = {2017},
date = {2017-11-01},
journal = {Fuel},
volume = {207},
pages = {790--800},
publisher = {Elsevier Ltd},
abstract = {The objective of this work is to investigate experimentally the formation of polycyclic aromatic hydrocarbons (PAH) during the combustion of biomass in a drop tube furnace (DTF). A number of biomass fuels, including furniture residues, grape pomace, kiwi residues, olive residues, wheat straw, rice husk and platanus residues were used in this work, with the tests performed at three temperatures (900, 1000 and 1100 °C). The solid fuels feed rate was 23 g/h and the total air flow rate was 4 L/min, ensuring a residence time in the DTF of around 2 s. In order to collect the PAH in the effluent gas, a narrow tube containing XAD-2 resin was connected to the flue gas duct of the DTF. A quartz fiber filter was placed just before it to collect the particulate matter, including soot, present in the flue gas. The analysis and quantification of the PAH combined Soxhlet extraction and gas chromatograph-mass spectrometer. Flue gas concentrations of O2, CO2, CO, hydrocarbons and NOx were measured to gather information regarding the combustion conditions. The results showed two distinct features for the variation of the total PAH emissions: one decreasing with temperature and other with a maximum at 1000 °C. Grape pomace, kiwi residues and platanus residues presented the lowest PAHs emission (20.8–54.2 mg PAH/kg fuel). A direct relation between the total amount of PAHs and the toxic equivalency value was found.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The objective of this work is to investigate experimentally the formation of polycyclic aromatic hydrocarbons (PAH) during the combustion of biomass in a drop tube furnace (DTF). A number of biomass fuels, including furniture residues, grape pomace, kiwi residues, olive residues, wheat straw, rice husk and platanus residues were used in this work, with the tests performed at three temperatures (900, 1000 and 1100 °C). The solid fuels feed rate was 23 g/h and the total air flow rate was 4 L/min, ensuring a residence time in the DTF of around 2 s. In order to collect the PAH in the effluent gas, a narrow tube containing XAD-2 resin was connected to the flue gas duct of the DTF. A quartz fiber filter was placed just before it to collect the particulate matter, including soot, present in the flue gas. The analysis and quantification of the PAH combined Soxhlet extraction and gas chromatograph-mass spectrometer. Flue gas concentrations of O2, CO2, CO, hydrocarbons and NOx were measured to gather information regarding the combustion conditions. The results showed two distinct features for the variation of the total PAH emissions: one decreasing with temperature and other with a maximum at 1000 °C. Grape pomace, kiwi residues and platanus residues presented the lowest PAHs emission (20.8–54.2 mg PAH/kg fuel). A direct relation between the total amount of PAHs and the toxic equivalency value was found.
2016
Colom-Díaz, Juan Manuel; Alzueta, María U; Christensen, Jakob M; Glarborg, Peter; Cordtz, Rasmus; Schramm, Jesper
Importance of Vanadium-Catalyzed Oxidation of SO2 to SO3 in Two-Stroke Marine Diesel Engines Artículo de revista
En: Energy and Fuels, vol. 30, no 7, pp. 6098–6102, 2016, ISSN: 15205029.
@article{Colom2016,
title = {Importance of Vanadium-Catalyzed Oxidation of SO2 to SO3 in Two-Stroke Marine Diesel Engines},
author = {Juan Manuel Colom-Díaz and María U Alzueta and Jakob M Christensen and Peter Glarborg and Rasmus Cordtz and Jesper Schramm},
url = {https://pubs.acs.org/sharingguidelines},
doi = {10.1021/acs.energyfuels.6b00638},
issn = {15205029},
year = {2016},
date = {2016-07-01},
journal = {Energy and Fuels},
volume = {30},
number = {7},
pages = {6098--6102},
publisher = {American Chemical Society},
abstract = {Low-speed marine diesel engines are mostly operated on heavy fuel oils, which have a high content of sulfur and ash, including trace amounts of vanadium, nickel, and aluminum. In particular, vanadium oxides could catalyze in-cylinder oxidation of SO2 to SO3, promoting the formation of sulfuric acid and enhancing problems of corrosion. In the present work, the kinetics of the catalyzed oxidation was studied in a fixed-bed reactor at atmospheric pressure. Vanadium oxide nanoparticles were synthesized by spray flame pyrolysis, i.e., by a mechanism similar to the mechanism leading to the formation of the catalytic species within the engine. Experiments with different particle compositions (vanadium/sodium ratio) and temperatures (300-800 °C) show that both the temperature and sodium content have a major impact on the oxidation rate. Kinetic parameters for the catalyzed reaction are determined, and the proposed kinetic model fits well with the experimental data. The impact of the catalytic reaction is studied with a phenomenological zero-dimensional (0D) engine model, where fuel oxidation and SOx formation is modeled with a comprehensive gas-phase reaction mechanism. Results indicate that the oxidation of SO2 to SO3 in the cylinder is dominated by gas-phase reactions and that the vanadium-catalyzed reaction is at most a very minor pathway.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Low-speed marine diesel engines are mostly operated on heavy fuel oils, which have a high content of sulfur and ash, including trace amounts of vanadium, nickel, and aluminum. In particular, vanadium oxides could catalyze in-cylinder oxidation of SO2 to SO3, promoting the formation of sulfuric acid and enhancing problems of corrosion. In the present work, the kinetics of the catalyzed oxidation was studied in a fixed-bed reactor at atmospheric pressure. Vanadium oxide nanoparticles were synthesized by spray flame pyrolysis, i.e., by a mechanism similar to the mechanism leading to the formation of the catalytic species within the engine. Experiments with different particle compositions (vanadium/sodium ratio) and temperatures (300-800 °C) show that both the temperature and sodium content have a major impact on the oxidation rate. Kinetic parameters for the catalyzed reaction are determined, and the proposed kinetic model fits well with the experimental data. The impact of the catalytic reaction is studied with a phenomenological zero-dimensional (0D) engine model, where fuel oxidation and SOx formation is modeled with a comprehensive gas-phase reaction mechanism. Results indicate that the oxidation of SO2 to SO3 in the cylinder is dominated by gas-phase reactions and that the vanadium-catalyzed reaction is at most a very minor pathway.