Call: +34 876555483
Email: abrego@unizar.es
Address: Office 31.080 c/Mariano Esquillor SN Edificio I+D+i, I3A, GPT Zaragoza Aragón
ABOUT ME
Research Interests
Broadly, my research focus is on pyrolysis of organic waste and biomass. I am currently interested in the development of new and/or improved thermochemical processes for biofuels and bioproducts.
Specifically, we are now developing a carbon-negative pyrolysis system with autothermal operation. Operational tests are ongoing. We seek to further develop and scale-up this idea, ideally with an industry partner.
Simultaneously, I work in the development of integrated valorization approaches of various agricultural or animal residues via pyrolysis, and its integration with biomethane production.
I have also collaborated in the development of the Flash Carbonization technology developed by Professor Michael J. Antal at University of Hawai’i as a Visiting Scholar, and worked at Instituto de Carboquímica (Spanish National Research Council), both in postdoctoral positions.
Previously to my PhD research, I also worked in gasification (fluidized bed and downdraft reactors) at demonstration scale.
PUBLICATIONS
2017
Garcia-Nunez, J A; Pelaez-Samaniego, M R; Garcia-Perez, Martha Estrella; Fonts, Isabel; Ábrego, Javier; Westerhof, R J M; Garcia-Perez, Manuel
Historical Developments of Pyrolysis Reactors: A Review Journal Article
In: vol. 31, no. 6, pp. 5751–5775, 2017, ISSN: 15205029.
@article{Garcia-Nunez2017,
title = {Historical Developments of Pyrolysis Reactors: A Review},
author = {J A Garcia-Nunez and M R Pelaez-Samaniego and Martha Estrella Garcia-Perez and Isabel Fonts and Javier Ábrego and R J M Westerhof and Manuel Garcia-Perez},
url = {https://pubs.acs.org/sharingguidelines},
doi = {10.1021/acs.energyfuels.7b00641},
issn = {15205029},
year = {2017},
date = {2017-06-01},
booktitle = {Energy and Fuels},
volume = {31},
number = {6},
pages = {5751--5775},
publisher = {American Chemical Society},
abstract = {This paper provides a review of pyrolysis technologies, focusing on reactor designs and companies commercializing these technologies. The renewed interest in pyrolysis is driven by the potential to convert lignocellulosic materials into bio-oil and biochar and the use of these intermediates for the production of biofuels, biochemicals, and engineered biochars for environmental services. This review presents slow, intermediate, fast, and microwave pyrolysis as complementary technologies that share some commonalities in their designs. While slow pyrolysis technologies (traditional carbonization kilns) use wood trunks to produce char chunks for cooking, fast pyrolysis systems process small particles to maximize bio-oil yield. The realization of the environmental issues associated with the use of carbonization technologies and the technical difficulties of operating fast pyrolysis reactors using sand as the heating medium and large volumes of carrier gas, as well as the problems with refining the resulting highly oxygenated oils, are forcing the thermochemical conversion community to rethink the design and use of these reactors. Intermediate pyrolysis reactors (also known as converters) offer opportunities for the large-scale balanced production of char and bio-oil. The capacity of these reactors to process forest and agricultural wastes without much preprocessing is a clear advantage. Microwave pyrolysis is an option for modular small autonomous devices for solid waste management. Herein, the evolution of pyrolysis technology is presented from a historical perspective; thus, old and new innovative designs are discussed together.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This paper provides a review of pyrolysis technologies, focusing on reactor designs and companies commercializing these technologies. The renewed interest in pyrolysis is driven by the potential to convert lignocellulosic materials into bio-oil and biochar and the use of these intermediates for the production of biofuels, biochemicals, and engineered biochars for environmental services. This review presents slow, intermediate, fast, and microwave pyrolysis as complementary technologies that share some commonalities in their designs. While slow pyrolysis technologies (traditional carbonization kilns) use wood trunks to produce char chunks for cooking, fast pyrolysis systems process small particles to maximize bio-oil yield. The realization of the environmental issues associated with the use of carbonization technologies and the technical difficulties of operating fast pyrolysis reactors using sand as the heating medium and large volumes of carrier gas, as well as the problems with refining the resulting highly oxygenated oils, are forcing the thermochemical conversion community to rethink the design and use of these reactors. Intermediate pyrolysis reactors (also known as converters) offer opportunities for the large-scale balanced production of char and bio-oil. The capacity of these reactors to process forest and agricultural wastes without much preprocessing is a clear advantage. Microwave pyrolysis is an option for modular small autonomous devices for solid waste management. Herein, the evolution of pyrolysis technology is presented from a historical perspective; thus, old and new innovative designs are discussed together.
Ruiz-Gómez, Nadia; Quispe, Violeta; Ábrego, Javier; Atienza-Martínez, María; Murillo, María Benita; Gea, Gloria
Co-pyrolysis of sewage sludge and manure Journal Article
In: Waste Management, vol. 59, pp. 211–221, 2017, ISSN: 18792456.
@article{Ruiz-Gomez2017,
title = {Co-pyrolysis of sewage sludge and manure},
author = {Nadia Ruiz-Gómez and Violeta Quispe and Javier Ábrego and María Atienza-Martínez and María Benita Murillo and Gloria Gea},
doi = {10.1016/j.wasman.2016.11.013},
issn = {18792456},
year = {2017},
date = {2017-01-01},
journal = {Waste Management},
volume = {59},
pages = {211--221},
publisher = {Elsevier Ltd},
abstract = {The management and valorization of residual organic matter, such as sewage sludge and manure, is gaining interest because of the increasing volume of these residues, their localized generation and the related problems. The anaerobic digestion of mixtures of sewage sludge and manure could be performed due to the similarities between both residues. The purpose of this study is to evaluate the feasibility of the co-pyrolysis of sewage sludge (SS) and digested manure (DM) as a potential management technology for these residues. Pyrolysis of a sewage sludge/manure blend (50:50%) was performed at 525 °C in a stirred batch reactor under N2 atmosphere. The product yields and some characteristics of the product were analyzed and compared to the results obtained in the pyrolysis of pure residues. Potential synergetic and antagonist effects during the co-pyrolysis process were evaluated. Although sewage sludge and manure seem similar in nature, there are differences in their pyrolysis product properties and distribution due to their distinct ash and organic matter composition. For the co-pyrolysis of SS and DM, the product yields did not show noticeable synergistic effects with the exception of the yields of organic compounds, being slightly higher than the predicted average, and the H2 yield, being lower than expected. Co-pyrolysis of SS and DM could be a feasible management alternative for these residues in locations where both residues are generated, since the benefits and the drawbacks of the co-pyrolysis are similar to those of the pyrolysis of each residue.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The management and valorization of residual organic matter, such as sewage sludge and manure, is gaining interest because of the increasing volume of these residues, their localized generation and the related problems. The anaerobic digestion of mixtures of sewage sludge and manure could be performed due to the similarities between both residues. The purpose of this study is to evaluate the feasibility of the co-pyrolysis of sewage sludge (SS) and digested manure (DM) as a potential management technology for these residues. Pyrolysis of a sewage sludge/manure blend (50:50%) was performed at 525 °C in a stirred batch reactor under N2 atmosphere. The product yields and some characteristics of the product were analyzed and compared to the results obtained in the pyrolysis of pure residues. Potential synergetic and antagonist effects during the co-pyrolysis process were evaluated. Although sewage sludge and manure seem similar in nature, there are differences in their pyrolysis product properties and distribution due to their distinct ash and organic matter composition. For the co-pyrolysis of SS and DM, the product yields did not show noticeable synergistic effects with the exception of the yields of organic compounds, being slightly higher than the predicted average, and the H2 yield, being lower than expected. Co-pyrolysis of SS and DM could be a feasible management alternative for these residues in locations where both residues are generated, since the benefits and the drawbacks of the co-pyrolysis are similar to those of the pyrolysis of each residue.
2015
Atienza-Martínez, María; Mastral, José Francisco; Ábrego, Javier; Ceamanos, Jesús; Gea, Gloria
Sewage sludge torrefaction in an auger reactor Journal Article
In: Energy and Fuels, vol. 29, no. 1, pp. 160–170, 2015, ISSN: 15205029.
@article{Atienza-Martinez2015b,
title = {Sewage sludge torrefaction in an auger reactor},
author = {María Atienza-Martínez and José Francisco Mastral and Javier Ábrego and Jesús Ceamanos and Gloria Gea},
url = {https://pubs.acs.org/sharingguidelines},
doi = {10.1021/ef501425h},
issn = {15205029},
year = {2015},
date = {2015-01-01},
journal = {Energy and Fuels},
volume = {29},
number = {1},
pages = {160--170},
publisher = {American Chemical Society},
abstract = {A lab-scale auger reactor was used for the study of dry sewage sludge torrefaction. The influence of the torrefaction temperature (between 250 and 300 °C) and the solid residence time (between 13 and 35 min) on the product distribution and properties was investigated. The results have shown that both parameters affect dry sewage sludge torrefaction products to a similar extent within the ranges of study. The yield of torrefied sewage sludge decreases when increasing the torrefaction temperature and the solid residence time, while the yields of liquid and noncondensable gases show the opposite trend. Carbon dioxide and hydrogen sulfide are the major noncondensable products. The yield of water is higher than the initial moisture content of sewage sludge. Organic compounds are also released during torrefaction, especially under severe conditions. Torrefaction liquid separates into an organic phase and an aqueous phase. The former is rich in oxygen-containing aliphatic compounds and steroids and their derivatives. The latter is rich in oxygen-containing aliphatic compounds and oxygen- and nitrogen-containing aliphatic compounds. Torrefaction pretreatment eases sewage sludge grindability and improves some of its fuel properties. O/C and H/C molar ratios of the torrefied solid are lower than those of the dry sewage sludge, while the higher heating value (daf) is higher. The energy density is higher under specific torrefaction conditions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
A lab-scale auger reactor was used for the study of dry sewage sludge torrefaction. The influence of the torrefaction temperature (between 250 and 300 °C) and the solid residence time (between 13 and 35 min) on the product distribution and properties was investigated. The results have shown that both parameters affect dry sewage sludge torrefaction products to a similar extent within the ranges of study. The yield of torrefied sewage sludge decreases when increasing the torrefaction temperature and the solid residence time, while the yields of liquid and noncondensable gases show the opposite trend. Carbon dioxide and hydrogen sulfide are the major noncondensable products. The yield of water is higher than the initial moisture content of sewage sludge. Organic compounds are also released during torrefaction, especially under severe conditions. Torrefaction liquid separates into an organic phase and an aqueous phase. The former is rich in oxygen-containing aliphatic compounds and steroids and their derivatives. The latter is rich in oxygen-containing aliphatic compounds and oxygen- and nitrogen-containing aliphatic compounds. Torrefaction pretreatment eases sewage sludge grindability and improves some of its fuel properties. O/C and H/C molar ratios of the torrefied solid are lower than those of the dry sewage sludge, while the higher heating value (daf) is higher. The energy density is higher under specific torrefaction conditions.
2013
García, Gorka; Monzón, Antonio; Bimbela, Fernando; Sánchez, José Luis; Ábrego, Javier
Desulfurization and Catalytic Gas Cleaning in Fluidized-Bed Co-gasification of Sewage Sludge–Coal Blends Journal Article
In: Energy & Fuels, vol. 27, no. 5, pp. 2846–2856, 2013, ISSN: 0887-0624.
@article{Garcia2013c,
title = {Desulfurization and Catalytic Gas Cleaning in Fluidized-Bed Co-gasification of Sewage Sludge–Coal Blends},
author = {Gorka García and Antonio Monzón and Fernando Bimbela and José Luis Sánchez and Javier Ábrego},
url = {http://dx.doi.org/10.1021/ef400259g},
issn = {0887-0624},
year = {2013},
date = {2013-05-01},
journal = {Energy & Fuels},
volume = {27},
number = {5},
pages = {2846--2856},
publisher = {American Chemical Society},
abstract = {Energy recovery from digested sewage sludge can be achieved by means of co-gasification with coal in a fluidized-bed system. In this regard, one of the main hurdles in developing a feasible process is the need for gas cleaning, with special emphasis on desulfurization and minimization of the tar content of the product gas. In this work, high-temperature catalytic gas cleaning was investigated by means of two fixed beds placed in series downstream of the gasification system: the first containing dolomite for desulfurization and primary tar cracking and the second containing a nickel-based catalyst for additional gas reforming. The effect of the temperature on the performance of the Ni catalyst bed (800?900 °C) was assessed. The use of dolomite in a secondary bed at 800 °C allowed for a significant reduction in both tar [15?0.21 g/m3 standard temperature and pressure (STP)] and H2S (to less than 0.01%) and an increase in the heating value of the gas [lower heating value (LHV) from 2000 to 2800 kJ/m3 STP]. The use of the Ni catalyst decreased the tar content of the gas to undetectable levels. The best results were obtained with the Ni-based catalyst at 800 °C, in terms of enhanced LHV (increasing from 2000 to 3300 kJ/m3 STP), gas production, which increased from around 2.40 to 2.75 m3 STP/kg on a dry and ash-free basis (daf), and energy requirements for the process. However, some evidence of Ni catalyst deactivation was found when operating under these conditions. Energy recovery from digested sewage sludge can be achieved by means of co-gasification with coal in a fluidized-bed system. In this regard, one of the main hurdles in developing a feasible process is the need for gas cleaning, with special emphasis on desulfurization and minimization of the tar content of the product gas. In this work, high-temperature catalytic gas cleaning was investigated by means of two fixed beds placed in series downstream of the gasification system: the first containing dolomite for desulfurization and primary tar cracking and the second containing a nickel-based catalyst for additional gas reforming. The effect of the temperature on the performance of the Ni catalyst bed (800?900 °C) was assessed. The use of dolomite in a secondary bed at 800 °C allowed for a significant reduction in both tar [15?0.21 g/m3 standard temperature and pressure (STP)] and H2S (to less than 0.01%) and an increase in the heating value of the gas [lower heating value (LHV) from 2000 to 2800 kJ/m3 STP]. The use of the Ni catalyst decreased the tar content of the gas to undetectable levels. The best results were obtained with the Ni-based catalyst at 800 °C, in terms of enhanced LHV (increasing from 2000 to 3300 kJ/m3 STP), gas production, which increased from around 2.40 to 2.75 m3 STP/kg on a dry and ash-free basis (daf), and energy requirements for the process. However, some evidence of Ni catalyst deactivation was found when operating under these conditions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Energy recovery from digested sewage sludge can be achieved by means of co-gasification with coal in a fluidized-bed system. In this regard, one of the main hurdles in developing a feasible process is the need for gas cleaning, with special emphasis on desulfurization and minimization of the tar content of the product gas. In this work, high-temperature catalytic gas cleaning was investigated by means of two fixed beds placed in series downstream of the gasification system: the first containing dolomite for desulfurization and primary tar cracking and the second containing a nickel-based catalyst for additional gas reforming. The effect of the temperature on the performance of the Ni catalyst bed (800?900 °C) was assessed. The use of dolomite in a secondary bed at 800 °C allowed for a significant reduction in both tar [15?0.21 g/m3 standard temperature and pressure (STP)] and H2S (to less than 0.01%) and an increase in the heating value of the gas [lower heating value (LHV) from 2000 to 2800 kJ/m3 STP]. The use of the Ni catalyst decreased the tar content of the gas to undetectable levels. The best results were obtained with the Ni-based catalyst at 800 °C, in terms of enhanced LHV (increasing from 2000 to 3300 kJ/m3 STP), gas production, which increased from around 2.40 to 2.75 m3 STP/kg on a dry and ash-free basis (daf), and energy requirements for the process. However, some evidence of Ni catalyst deactivation was found when operating under these conditions. Energy recovery from digested sewage sludge can be achieved by means of co-gasification with coal in a fluidized-bed system. In this regard, one of the main hurdles in developing a feasible process is the need for gas cleaning, with special emphasis on desulfurization and minimization of the tar content of the product gas. In this work, high-temperature catalytic gas cleaning was investigated by means of two fixed beds placed in series downstream of the gasification system: the first containing dolomite for desulfurization and primary tar cracking and the second containing a nickel-based catalyst for additional gas reforming. The effect of the temperature on the performance of the Ni catalyst bed (800?900 °C) was assessed. The use of dolomite in a secondary bed at 800 °C allowed for a significant reduction in both tar [15?0.21 g/m3 standard temperature and pressure (STP)] and H2S (to less than 0.01%) and an increase in the heating value of the gas [lower heating value (LHV) from 2000 to 2800 kJ/m3 STP]. The use of the Ni catalyst decreased the tar content of the gas to undetectable levels. The best results were obtained with the Ni-based catalyst at 800 °C, in terms of enhanced LHV (increasing from 2000 to 3300 kJ/m3 STP), gas production, which increased from around 2.40 to 2.75 m3 STP/kg on a dry and ash-free basis (daf), and energy requirements for the process. However, some evidence of Ni catalyst deactivation was found when operating under these conditions.
García, Gorka; Arauzo, Jesús; Gonzalo, Alberto; Sánchez, José Luis; Ábrego, Javier
Influence of feedstock composition in fluidised bed co-gasification of mixtures of lignite, bituminous coal and sewage sludge Journal Article
In: Chemical Engineering Journal, vol. 222, pp. 345–352, 2013, ISSN: 13858947.
@article{Garcia2013a,
title = {Influence of feedstock composition in fluidised bed co-gasification of mixtures of lignite, bituminous coal and sewage sludge},
author = {Gorka García and Jesús Arauzo and Alberto Gonzalo and José Luis Sánchez and Javier Ábrego},
url = {http://www.sciencedirect.com/science/article/pii/S1385894713002398},
issn = {13858947},
year = {2013},
date = {2013-04-01},
journal = {Chemical Engineering Journal},
volume = {222},
pages = {345--352},
abstract = {Energy recovery from sewage sludge can be achieved by several thermochemical processes, including its co-processing with other fuels. In this work, co-gasification of mixtures of sewage sludge with two types of coal (bituminous and lignite) was performed in a laboratory-scale fluidised bed reactor. The influence of the feedstock composition on key parameters of gasification—such as gas heating value and yield, cold gas efficiency and tar generation—was determined. Whereas some of these results can be explained as the sum of individual contributions of each feedstock component, some synergistic effects were also identified. Among these, the decrease of tar yield and the increase of H2 and CO in the gas suggest that co-gasification of sewage sludge with certain types of coal may be energetically advantageous and improve the process performance.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Energy recovery from sewage sludge can be achieved by several thermochemical processes, including its co-processing with other fuels. In this work, co-gasification of mixtures of sewage sludge with two types of coal (bituminous and lignite) was performed in a laboratory-scale fluidised bed reactor. The influence of the feedstock composition on key parameters of gasification—such as gas heating value and yield, cold gas efficiency and tar generation—was determined. Whereas some of these results can be explained as the sum of individual contributions of each feedstock component, some synergistic effects were also identified. Among these, the decrease of tar yield and the increase of H2 and CO in the gas suggest that co-gasification of sewage sludge with certain types of coal may be energetically advantageous and improve the process performance.