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Ahmad, W., Lin, L. & Strand, M. (2024). Investigation of different configurations of alumina packed bed reactor for coke free conversion of benzene. Chemical engineering research & design, 201, 433-445
Open this publication in new window or tab >>Investigation of different configurations of alumina packed bed reactor for coke free conversion of benzene
2024 (English)In: Chemical engineering research & design, ISSN 0263-8762, E-ISSN 1744-3563, Vol. 201, p. 433-445Article in journal (Refereed) Published
Abstract [en]

Conversion of producer gas tar without coke generation is a great challenge. This study investigates conversion of tar model benzene using different configurations of highly non-porous ɣ-Al2O3 packed bed reactor at 1000–1100 0C. The configurations comprised of different positions (relative to top (P1), center (P2) and bottom (P3) of reactor furnace), heights (5, 13 and 25 cm) and particles sizes (0.5, 3 and 5 mm) of alumina packed bed. Steam and CO2 were used as reforming media for tested benzene concentrations (0.4–1.8 vol%). The results showed benzene conversions of 48–91% with negligible steady thin coke generation using a packed bed (height: 25 cm, particles size: 3 mm) at P1. Whereas, relative high benzene conversions of 63–93 and 68–95% at P2 and P3 respectively with unsteady thick coke generation at benzene concentrations greater than 0.4 vol% increased differential upstream pressures (DUPs) of beds. Similar unsteady coke generation at benzene concentrations greater than 0.8 vol% and temperature of 1100 0C was observed with packed beds of heights of 5 and 13 cm, and particles size of 0.5 mm at P1. Generation of unsteady coke with condensed structure as evidenced by its characterization was attributable to increased benzene polymerization and reduced bed surface gasification reactions due to improperly installed packed bed. Developed kinetic model predicted well the generated coke. As conclusion, properly installed alumina packed bed pertaining to tar concentration and other experimental conditions may inhibit coke generation during tar conversion.

Place, publisher, year, edition, pages
Elsevier, 2024
National Category
Energy Engineering
Research subject
Technology (byts ev till Engineering), Bioenergy Technology
Identifiers
urn:nbn:se:lnu:diva-126019 (URN)10.1016/j.cherd.2023.11.063 (DOI)001139578000001 ()2-s2.0-85180412311 (Scopus ID)
Available from: 2023-12-18 Created: 2023-12-18 Last updated: 2024-02-01Bibliographically approved
Ahmad, W., Lin, L. & Strand, M. (2023). Coke-free conversion of benzene at high temperatures. Journal of the Energy Institute, 109, Article ID 101307.
Open this publication in new window or tab >>Coke-free conversion of benzene at high temperatures
2023 (English)In: Journal of the Energy Institute, ISSN 1743-9671, E-ISSN 1746-0220, Vol. 109, article id 101307Article in journal (Refereed) Published
Abstract [en]

This study investigates the conversion of benzene in a novel highly non-porous ɣ-Al2O3 packed bed reactor at 1000–1100 °C. The influences of packed bed presence, reforming medium (steam and CO2), gas flow rate and benzene concentration on steady state benzene conversion are examined. In presence of packed bed, benzene conversions of 52, 75, and 84% were achieved with combined steam and CO2 reforming at 1000, 1050, and 1100 °C, respectively. Whereas, benzene conversion of 65% without the packed bed at 1000 °C experienced a continuous increase in differential upstream pressure (DUP) of high temperature (HT) filter at reactor downstream due to deposition of in situ generated coke. High concentrations of generated CO and H2 of 2.3 and 6 vol% with packed bed than 1.4 and 4.7 vol% without the packed respectively, were achieved. CO2 reforming achieved high benzene conversions of 68–98% than 42–80% achieved with stream reforming at packed bed reactor temperatures of 1000–1100 °C. The results indicated that presence of ɣ-Al2O3 packed bed with possible surface reactions directed the conversion of benzene to combustible gases instead of coke. Hence, ɣ-Al2O3 packed bed reactor could be a suitable choice for coke-free conversion of tar of gasifier producer gas.

Place, publisher, year, edition, pages
Elsevier, 2023
Keywords
Steam reforming, CO reforming, Benzene conversion, Coke deposits, Combustible gases
National Category
Energy Engineering Bioenergy Chemical Process Engineering
Research subject
Technology (byts ev till Engineering), Bioenergy Technology
Identifiers
urn:nbn:se:lnu:diva-122025 (URN)10.1016/j.joei.2023.101307 (DOI)001025198800001 ()2-s2.0-85161330969 (Scopus ID)
Available from: 2023-06-16 Created: 2023-06-16 Last updated: 2023-11-14Bibliographically approved
Ahmad, W., Lin, L. & Strand, M. (2022). Benzene conversion using a partial combustion approach in a packed bed reactor. Energy, 239(Part C), Article ID 122251.
Open this publication in new window or tab >>Benzene conversion using a partial combustion approach in a packed bed reactor
2022 (English)In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 239, no Part C, article id 122251Article in journal (Refereed) Published
Abstract [en]

This study investigates the partial combustion technique for tar conversion using a modified experimental set up comprising a packed bed reactor with bed-inside probe for air supply. Simulated producer gas (SPG) and benzene were selected as a real producer gas alternative and model tar component respectively. The benzene conversion was investigated under different experimental conditions such as reactor temperature (650–900 °C), packed bed height (0–12 cm), residence time (1.2–1.9 s), air fuel ratio (0.2 and 0.3) and SPG composition. The results showed insignificant effect of temperature over benzene conversion while air fuel ratio of 0.3 caused high benzene conversion than at 0.2. Absence of packed bed lead high benzene conversion of 90% to polyaromatic hydrocarbons (PAHs) compared to similar low PAHs free benzene conversion of 32% achieved at both packed heights. In SPG composition effect, H2 and CH4 had a substantial inverse effect on benzene conversion. An increase in H2 concentration from 12 to 24 vol% increased the benzene conversion from 26 to 45% while an increase in CH4 concentration from 7 to 14 vol% reduced the benzene conversion from 28 to 4%. However, other SPG components had insignificant impacts on benzene conversion.

Place, publisher, year, edition, pages
Elsevier, 2022
Keywords
Partial combustion, Gasification, Tar, Simulated producer gas
National Category
Chemical Process Engineering
Research subject
Technology (byts ev till Engineering), Sustainable Built Environment
Identifiers
urn:nbn:se:lnu:diva-107478 (URN)10.1016/j.energy.2021.122251 (DOI)000711155600008 ()2-s2.0-85116867387 (Scopus ID)2021 (Local ID)2021 (Archive number)2021 (OAI)
Projects
Char and tar conversion in an internally heated packed bed
Available from: 2021-10-14 Created: 2021-10-14 Last updated: 2023-06-21Bibliographically approved
Pettersson, J., Andersson, S., Bäfver, L. & Strand, M. (2019). Investigation of the Collection Efficiency of a Wet Electrostatic Precipitator at a Municipal Solid Waste-Fueled Combined Heat and Power Plant Using Various Measuring Methods. Energy & Fuels, 33(6), 5282-5292
Open this publication in new window or tab >>Investigation of the Collection Efficiency of a Wet Electrostatic Precipitator at a Municipal Solid Waste-Fueled Combined Heat and Power Plant Using Various Measuring Methods
2019 (English)In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 33, no 6, p. 5282-5292Article in journal (Refereed) Published
Abstract [en]

This article reports results from measurements of mainly submicrometer particles at the inlet and outlet of a newly designed industrial wet electrostatic precipitator (WESP) in a combined heat and power plant fueled with municipal solid waste. The measurements were carried out with dual electric low-pressure impactors in parallel at the precipitator inlet and outlet. In addition, measurements were carried out with traditional total dust filters, low-pressure impactors, a scanning mobility particle sizer, and an aerodynamic particle sizer. The measurements aimed to characterize the aerosol particles and measure the efficiency of the WESP with special attention to fine and ultrafine particles. In general, the WESP performance and response to varying conditions was found to be in line with predictions made for the design. The WESP featured a cooled collector surface, but based on the limited results, no conclusion could be drawn regarding any possible improvement from collector cooling. The characterization of the aerosol particulate matter was challenging because of fast fluctuations in particle concentration. Methodological considerations are pointed out, mainly regarding the SMPS and ELPI measuring systems.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2019
National Category
Chemical Process Engineering
Research subject
Technology (byts ev till Engineering), Bioenergy Technology
Identifiers
urn:nbn:se:lnu:diva-86919 (URN)10.1021/acs.energyfuels.9b00373 (DOI)000472800900057 ()2-s2.0-85067919542 (Scopus ID)
Available from: 2019-07-18 Created: 2019-07-18 Last updated: 2022-12-07Bibliographically approved
Razmjoo, N., Hermansson, S., Morgalla, M. & Strand, M. (2019). Study of the transient release of water vapor from a fuel bed of wet biomass in a reciprocating-grate furnace. Journal of the Energy Institute, 92(4), 843-854
Open this publication in new window or tab >>Study of the transient release of water vapor from a fuel bed of wet biomass in a reciprocating-grate furnace
2019 (English)In: Journal of the Energy Institute, ISSN 1743-9671, E-ISSN 1746-0220, Vol. 92, no 4, p. 843-854Article in journal (Refereed) Published
Abstract [en]

The present study investigates how sudden changes in fuel moisture affected the combustion characteristics of the fuel bed in a 4-MW reciprocating-grate furnace. The moisture content of the fuel fed to the furnace was monitored online using a near-infrared spectroscopy device, and the water vapor concentration in the flue gas was measured continuously. To obtain experimental data on fuel-bed conditions, the temperature and gas composition in the bed were measured using a probe. A simplified drying model was developed using the measured gas composition values as inputs. The model was then used to estimate the drying rate and to simulate the extent of the drying zone along the grate. Measurements indicated that a change in the moisture content of the fuel fed to the furnace was detected as a change in water vapor concentration in the flue gas with a delay of about 2 h. The model predicted that a portion of wet fuel would need about 2 h to become dry, in line with the measured time delay of the water vapor concentration change in the flue gas. Overall, there was good alignment between the measured and simulated results, supporting the validity of the model and the assumed mechanisms.

Place, publisher, year, edition, pages
Elsevier, 2019
National Category
Bioenergy
Research subject
Technology (byts ev till Engineering), Bioenergy Technology
Identifiers
urn:nbn:se:lnu:diva-77594 (URN)10.1016/j.joei.2018.06.014 (DOI)000473381000002 ()2-s2.0-85053155711 (Scopus ID)
Available from: 2018-09-06 Created: 2018-09-06 Last updated: 2023-11-14Bibliographically approved
Morgalla, M., Lin, L. & Strand, M. (2018). Benzene Conversion in a Packed Alumina Bed Continuously Fed with Woody Char Particles. Energy & Fuels, 32(7), 7670-7677
Open this publication in new window or tab >>Benzene Conversion in a Packed Alumina Bed Continuously Fed with Woody Char Particles
2018 (English)In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 32, no 7, p. 7670-7677Article in journal (Refereed) Published
Abstract [en]

This Article investigates the decomposition of benzene (as a model tar) over finely dispersed char particles continuously distributed into a packed bed. Fragmented char particles and benzene plus a gasification agent (H2O or CO2) were supplied into a ceramic reactor that was heated electrically. The supplied char particles were retained in the reactor by a bed of alumina grains. Woody char as well as iron-doped and potassium-doped woody char were used. The influence of the gasification agent, char concentration, char weight time (proportional to the instant char mass present in the bed), and bed temperature (600-1050 degrees C) was investigated. Increasing the char concentration and char weight time increased benzene conversions for all tested chars. At similar char weight times, the benzene conversion increased with temperature, whereas the iron- and potassium doped char did not affect the specific conversion. At similar char concentrations, changing the gasification agent from CO2 to steam as well as using doped char led to decreased benzene conversions. This can be explained by accelerated char gasification reactions and thus a diminished char mass in the packed bed. Furthermore, benzene conversion rates were enhanced in the presence of CO2 as compared to steam. As the temperature was increased from 950 to 1050 degrees C, the benzene conversions were slightly reduced. This was interpreted as a combined effect of the enhanced benzene conversion rates and reduced char weight times. The highest benzene conversions achieved in the experiments were approximately 80% at 950-1000 degrees C using CO2 as gasification agent and supplying approximately 20-30 g N m(-3) undoped woody char.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2018
National Category
Energy Engineering
Research subject
Technology (byts ev till Engineering), Bioenergy Technology
Identifiers
urn:nbn:se:lnu:diva-77403 (URN)10.1021/acs.energyfuels.8b01249 (DOI)000439661300038 ()2-s2.0-85048372503 (Scopus ID)
Available from: 2018-08-29 Created: 2018-08-29 Last updated: 2023-06-22Bibliographically approved
Morgalla, M., Lin, L. & Strand, M. (2018). Benzene conversion in a packed bed loaded with biomass char particles. Energy & Fuels, 32(1), 554-560
Open this publication in new window or tab >>Benzene conversion in a packed bed loaded with biomass char particles
2018 (English)In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 32, no 1, p. 554-560Article in journal (Refereed) Published
Abstract [en]

This study investigates the conversion of benzene in a packed bed containing fine char particles. Benzene and steam were simultaneously supplied to a tubular ceramic reactor that was heated electrically. Fragmented char particles were suspended and continuously supplied via a separate supply line. A packed bed of crushed alumina balls was positioned in the reactor to retain the char particles. The benzene conversion in the hot char bed was investigated by varying the bed temperature (900–1100 °C), steam concentration (0–27 vol %), and char concentration (5–50 g Nm–3). The highest conversions achieved in the experiments were approximately 75%. At comparable char concentrations, similar benzene conversions occurred at 900 and 1000 °C. Increasing the temperature to 1100 °C or increasing the steam concentration reduced the benzene conversion. The results indicate that the reduced conversion was due to enhanced char gasification reactions at elevated temperatures and steam concentrations and thus to reduced char mass in the packed bed.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2018
Keywords
Tar, char, biomass
National Category
Bioenergy
Research subject
Technology (byts ev till Engineering), Bioenergy Technology
Identifiers
urn:nbn:se:lnu:diva-69105 (URN)10.1021/acs.energyfuels.7b03236 (DOI)000423253200059 ()2-s2.0-85040791108 (Scopus ID)
Available from: 2017-12-06 Created: 2017-12-06 Last updated: 2023-06-22Bibliographically approved
Biollaz, S., Calbry-Muzyka, A., Rodriguez, S., Sárossy, Z., Ravenni, G., Fateev, A., . . . Ballesteros, R. (2018). Gas analysis in gasification of biomass and waste: Guideline report: Document 1. International Energy Agency (IEA)
Open this publication in new window or tab >>Gas analysis in gasification of biomass and waste: Guideline report: Document 1
Show others...
2018 (English)Report (Refereed)
Abstract [en]

Gasification is generally acknowledged as one of the technologies that will enable the large-scale production of biofuels and chemicals from biomass and waste. One of the main technical challenges associated to the deployment of biomass gasification as a commercial technology is the cleaning and upgrading of the product gas. The contaminants of product gas from biomass/waste gasification include dust, tars, alkali metals, BTX, sulphur-, nitrogen- and chlorine compounds, and heavy metals. Proper measurement of the components and contaminants of the product gas is essential for the monitoring of gasification-based plants (efficiency, product quality, by-products), as well as for the proper design of the downstream gas cleaning train (for example, scrubbers, sorbents, etc.). In practice, a trade-off between reliability, accuracy and cost has to be reached when selecting the proper analysis technique for a specific application. The deployment and implementation of inexpensive yet accurate gas analysis techniques to monitor the fate of gas contaminants might play an important role in the commercialization of biomass and waste gasification processes.

This special report commissioned by the IEA Bioenergy Task 33 group compiles a representative part of the extensive work developed in the last years by relevant actors in the field of gas analysis applied to(biomass and waste) gasification. The approach of this report has been based on the creation of a team of contributing partners who have supplied material to the report. This networking approach has been complemented with a literature review. The report is composed of a set of 2 documents. Document 1(the present report) describes the available analysis techniques (both commercial and underdevelopment) for the measurement of different compounds of interest present in gasification gas. The objective is to help the reader to properly select the analysis technique most suitable to the target compounds and the intended application. Document 1 also describes some examples of application of gas analysis at commercial-, pilot- and research gasification plants, as well as examples of recent and current joint research activities in the field. The information contained in Document 1 is complemented with a book of factsheets on gas analysis techniques in Document 2, and a collection of video blogs which illustrate some of the analysis techniques described in Documents 1 and 2.

This guideline report would like to become a platform for the reinforcement of the network of partners working on the development and application of gas analysis, thus fostering collaboration and exchange of knowledge. As such, this report should become a living document which incorporates in future coming progress and developments in the field.

Place, publisher, year, edition, pages
International Energy Agency (IEA), 2018. p. 161
Keywords
biomass, gasification, gas analysis, aerosol, particulate matter
National Category
Bioenergy Chemical Process Engineering
Research subject
Technology (byts ev till Engineering), Bioenergy Technology
Identifiers
urn:nbn:se:lnu:diva-78005 (URN)9781910154472 (ISBN)
Note

The work collected in this report has been the result of the joint effort and kind collaboration of a group of experts in the field of gas analysis and biomass gasification. The coordinators would like to warmly thank all the contributing partners for their generous support in sharing their material and experience for this report. It has been the sum of the experiences of this large group of experts that has added the value to this report. The collaborative effort would have been impossible without the use of existing networks. Serge Biollaz and York Neubauer, coordinators of the Gas Analysis group, are gratefully acknowledged for their kind cooperation, valuable advice and active support throughout the elaboration of this report. The members of the IEA Bioenergy Task 33 working group (Steering Group of this project) are gratefully acknowledged for the commitment and feedback throughout the project. Lastly, we would like to express our sincere thanks to the IEA Bioenergy Task 33 “Gasification of biomass and waste” for the funding of this special report.

Available from: 2018-09-25 Created: 2018-09-25 Last updated: 2023-06-21Bibliographically approved
Biollaz, S., Calbry-Muzyka, A., Rodriguez, S., Sárossy, Z., Ravenni, G., Fateev, A., . . . Ballesteros, R. (2018). Gas analysis in gasification of biomass and waste: Guideline report: Document 2 - Factsheets on gas analysis techniques. International Energy Agency (IEA)
Open this publication in new window or tab >>Gas analysis in gasification of biomass and waste: Guideline report: Document 2 - Factsheets on gas analysis techniques
Show others...
2018 (English)Report (Refereed)
Abstract [en]

Gasification is generally acknowledged as one of the technologies that will enable the large-scale production of biofuels and chemicals from biomass and waste. One of the main technical challenges associated to the deployment of biomass gasification as a commercial technology is the cleaning and upgrading of the product gas. The contaminants of product gas from biomass/waste gasification include dust, tars, alkali metals, BTX, sulphur-, nitrogen- and chlorine compounds, and heavy metals. Proper measurement of the components and contaminants of the product gas is essential for the monitoring of gasification-based plants (efficiency, product quality, by-products), as well as for the proper design of the downstream gas cleaning train (for example, scrubbers, sorbents, etc.). The deployment and implementation of inexpensive yet accurate gas analysis techniques to monitor the fate of gas contaminants might play an important role in the commercialization of biomass and waste gasification processes.

This special report commissioned by the IEA Bioenergy Task 33 group compiles a representative part of the extensive work developed in the last years by relevant actors in the field of gas analysis applied to (biomass and waste) gasification. The approach of this report has been based on the creation of a team of contributing partners who have supplied material to the report. This networking approach has been complemented with a literature review. This guideline report would like to become a platform for the reinforcement of the network of partners working on the development and application of gas analysis, thus fostering collaboration and exchange of knowledge. As such, this report should become a living document which incorporates in future coming progress and developments in the field.

Place, publisher, year, edition, pages
International Energy Agency (IEA), 2018. p. 141
Keywords
biomass, gasification, gas analysis, aerosol, particulate matter
National Category
Bioenergy Chemical Process Engineering
Research subject
Technology (byts ev till Engineering), Bioenergy Technology
Identifiers
urn:nbn:se:lnu:diva-78110 (URN)9781910154434 (ISBN)
Available from: 2018-10-01 Created: 2018-10-01 Last updated: 2023-06-21Bibliographically approved
Morgalla, M., Lin, L. & Strand, M. (2017). Decomposition of benzene using char aerosol particles dispersed in a high-temperature filter. Energy, 118, 1345-1352
Open this publication in new window or tab >>Decomposition of benzene using char aerosol particles dispersed in a high-temperature filter
2017 (English)In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 118, p. 1345-1352Article in journal (Refereed) Published
Abstract [en]

In this study the tar-removal suitability of char particles finely dispersed in a high-temperature filter was investigated. Benzene was selected as the model tar. An aerosol-based method was designed and used to investigate the benzene decomposition behaviour. Two types of char were used: commercially available activated charcoal and pine char prepared in the laboratory. The conversion behaviour of both chars was investigated in the temperature range between 750 and 900 °C using steam as the gasification medium. During the experiments, different benzene concentrations, amounts of deposited char and gas residence times were tested. The results indicate that both activated carbon and pine char reduced the benzene concentration. Activated carbon generally produced higher and more stable benzene conversions compared to the pine char particles. Decreasing the benzene concentration or increasing the gas residence time or char mass improved the benzene conversion. It was concluded that the char gasification rate became slower while benzene was simultaneously converted. The aerosol-based method was also used to investigate benzene decomposition behaviour while continuously supplying fresh char particles together with steam at 1000 °C. In that way, the deactivated and gasified char particles were steadily replaced, preventing the benzene conversion from decreasing over time.

Place, publisher, year, edition, pages
Elsevier, 2017
Keywords
Biomass, Gasification, Char, Tar, Particles
National Category
Bioenergy
Research subject
Technology (byts ev till Engineering), Bioenergy Technology
Identifiers
urn:nbn:se:lnu:diva-58100 (URN)10.1016/j.energy.2016.11.016 (DOI)000395048900116 ()2-s2.0-85006356091 (Scopus ID)
Funder
Swedish Energy Agency
Available from: 2016-11-11 Created: 2016-11-11 Last updated: 2023-06-22Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-1138-5105

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