A Prospective Study of the Exploitation of Pelagic Sargassum spp. as a Solid Biofuel Energy Source
, José Juan Alvarado-Flores 2, Juan Carlos Corral-Huacuz 1, Arturo Aguilera-Mandujano 3, Rosa E. Rodríguez-Martínez 4, Santiago José Guevara-Martínez 5, Jorge Víctor Alcaraz-Vera 6, José Guadalupe Rutiaga-Quiñones 2, Juan Zárate-Medina 3, María Liliana Ávalos-Rodríguez 7 and Mario Morales-Máximo 1,2,*Round 1
Reviewer 1 Report
A nice and interesting piece of work. I have a couple of comments where I hope the author will consider improving the work quality:
- The key results must be presented in the abstract,
- Re-express the energy content from GJ/m3 to GJ/kg dry wieght.
- The materials investigated has a lower caloric value vs wood and coal. The question, what is the significance for energy sources?
- Why not mentioning other potential uses as an adsorbent for heavy metal removal? See the suggested papers for referring and citation.
- Discuss the potential of using Sargassum spp. as source for biofuel production. See the suggested article below.
- What about the environmental effect of direct energy utilization? for example, if you use these materials in a direct combustion bioler there might be cases that are harmful to the humane and enviroment.
- In table nr 1, a huge amount of extractives 67.7-74.4% is presented. This is a huge amount and you need to discuss what kind of extractives? if you have a data of their composition analysis please mentioned. If you don't have, refer to the literature to find out what they could be and cite the work.
- Please refer to the please articles to help you tackle the above problems. Please cite the work as well:
https://0-link-springer-com.brum.beds.ac.uk/chapter/10.1007/978-90-481-8569-6_13
https://0-www-sciencedirect-com.brum.beds.ac.uk/science/article/abs/pii/S0960852413004768
https://0-link-springer-com.brum.beds.ac.uk/article/10.1023/B:JAPH.0000047779.31105.ec
https://0-www-sciencedirect-com.brum.beds.ac.uk/science/article/abs/pii/S0048969719301615
https://eis.hu.edu.jo/deanshipfiles/pub11030101797.pdf
https://journals.tubitak.gov.tr/chem/abstract.htm?id=20459
Author Response
Authors response to comments of the manuscript: Applied Sciences, Manuscript ID: applsci- 1010114
“A prospective Study of the Exploitation of Pelagic Sargassum spp. as a Solid Biofuel Energy Source”
by Luis Bernardo López-Sosa, José Juan Alvarado-Flores, Juan Carlos Corral Huacuz, Arturo Aguilera-Mandujano, Rosa E. Rodríguez-Martínez, Santiago José Guevara-Martínez, Jorge Víctor Alcaraz-Vera, José Guadalupe Rutiaga-Quiñones, Juan Zárate-Medina, María Liliana Ávalos-Rodríguez and Mario Morales-Máximo.
The authors would like to thank each reviewer for his/her constructive comments and suggestions to improve the quality of the manuscript. We have taken into account each comment in the revised version of the manuscript, which have led to include additional references, new graphics as well as add new sentences.
A particular response to comments offered by each reviewer is provided next:
Response to Reviewer #1
A nice and interesting piece of work. I have a couple of comments where I hope the author will consider improving the work quality:
The authors are grateful for the assessment of the paper, as well as for providing us with valuable comments and suggestions based on a careful reading of the original manuscript.
- The key results must be presented in the abstract,
Answer: The authors included the key results in the abstract of the manuscript.
- Re-express the energy content from GJ/m3 to GJ/kg dry wieght.
Answer: The authors now showed calorific value in MJ/Kg.
- The materials investigated has a lower caloric value vs wood and coal. The question, what is the significance for energy sources?
Answer: Thank you for your comment. The authors consider that the volume of Sargassum spp. in the Mexican Caribbean is high. And that although the calorific value is low, it can be used as a solid, liquid or gaseous biofuel. These algae can be used as direct fuels or as complementary materials for other biofuels with agricultural or residential waste. The authors included this discussion in the manuscript.
- Why not mentioning other potential uses as an adsorbent for heavy metal removal? See the suggested papers for referring and citation.
Answer: Thank you for your comment. The authors included in the manuscript the potential heavy metal absorption uses of Sargassum spp.; and include the suggested references.
- Discuss the potential of using Sargassum spp. as source for biofuel production. See the suggested article below.
Answer: Thank you. The authors included in the manuscript the potential for use of solid, liquid and gaseous biofuels.
- What about the environmental effect of direct energy utilization? for example, if you use these materials in a direct combustion bioler there might be cases that are harmful to the humane and enviroment.
Answer: Thank you for your comment. The authors included in the manuscript a section on gasifiers, as technologies to inhibit the generation of polluting gases and optimize the use of biofuels such as sargassum spp.
- In table nr 1, a huge amount of extractives 67.7-74.4% is presented. This is a huge amount and you need to discuss what kind of extractives? if you have a data of their composition analysis please mentioned. If you don't have, refer to the literature to find out what they could be and cite the work.
Answer: Thank you. The authors included a section in the manuscript on extractives, including the corresponding references.
- Please refer to the please articles to help you tackle the above problems. Please cite the work as well:
Answer: Thank you very much for your comments. The authors included all suggested references.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Comment to the paper: “A prospective Study of the Exploitation of Pelagic Sargassum spp. as a Solid Biofuel Energy Source” by Luis Bernardo López-Sosa et al.
General comment:
The manuscript deals with the assessment of the exploitation of pelagic Sargassum spp. as a solid biofuel energy source. Characterization of the biomass was carried out; moreover thermogravimetric and differential analyses were performed. Finally, the energetic potential considering the estimated volume of pelagic Sargassum spp. removed from beaches along the Mexican Caribbean coast was estimated.
The manuscript is suitable to be published in this journal, however some points should be addressed before publication.
Some minor language mistakes are present that should anyway be corrected.
- Introduction
Biomass has the ability to capture CO2, which is a fundamental characteristic when it is used as energy source in terms of CO2 balance. Please, include this point in the introduction by considering the following papers:
- Bench-scale cultivation of microalgae scenedesmus almeriensis for CO2 capture and lutein production (2019) Energies, 12 (14), art. no. 2806. DOI: 10.3390/en12142806
- Bioenergy with carbon emissions capture and utilisation towards GHG neutrality: Power-to-Gas storage via hydrothermal gasification (2020) Applied Energy, 280, art. no. 115923. DOI: 10.1016/j.apenergy.2020.115923
- Enhanced hydrogen production from catalytic biomass gasification with in-situ CO2 capture (2020) Environmental Pollution, 267, art. no. 115487. DOI: 10.1016/j.envpol.2020.115487
- Process integration of chemical looping combustion with oxygen uncoupling in a biomass-fired combined heat and power plant (2020) Energy, 210, art. no. 118550. DOI: 10.1016/j.energy.2020.118550
- Materials and methods
Please, specify if investigations were carried out in duplicate/triplicate etc.
Please, add standard deviation.
Please, include the elemental analysis of the biomass.
Please, clarify if the assessment of the char, that can be produced after thermal treatment, was carried out.
- Results
Please, improve comparison between your findings and literature data.
Please, include standard deviation.
Please, compare Pelagic Sargassum spp. and fossil fuels in terms of CO2 balance, i.e. CO2 emitted and removed from the atmosphere.
Comments for author File: 
Comments.pdf
Author Response
Authors response to comments of the manuscript: Applied Sciences, Manuscript ID: applsci- 1010114
“A prospective Study of the Exploitation of Pelagic Sargassum spp. as a Solid Biofuel Energy Source”
by Luis Bernardo López-Sosa, José Juan Alvarado-Flores, Juan Carlos Corral Huacuz, Arturo Aguilera-Mandujano, Rosa E. Rodríguez-Martínez, Santiago José Guevara-Martínez, Jorge Víctor Alcaraz-Vera, José Guadalupe Rutiaga-Quiñones, Juan Zárate-Medina, María Liliana Ávalos-Rodríguez and Mario Morales-Máximo.
The authors would like to thank each reviewer for his/her constructive comments and suggestions to improve the quality of the manuscript. We have taken into account each comment in the revised version of the manuscript, which have led to include additional references, new graphics as well as add new sentences.
A particular response to comments offered by each reviewer is provided next:
Response to Reviewer #2
The manuscript deals with the assessment of the exploitation of pelagic Sargassum spp. as a solid biofuel energy source. Characterization of the biomass was carried out; moreover thermogravimetric and differential analyses were performed. Finally, the energetic potential considering the estimated volume of pelagic Sargassum spp. removed from beaches along the Mexican Caribbean coast was estimated.
The manuscript is suitable to be published in this journal, however some points should be addressed before publication.
Some minor language mistakes are present that should anyway be corrected.
Answer: The authors are grateful for the assessment of the paper, as well as for providing us with valuable comments and suggestions based on a careful reading of the original manuscript
Introduction
Biomass has the ability to capture CO2, which is a fundamental characteristic when it is used as energy source in terms of CO2 balance. Please, include this point in the introduction by considering the following papers:
- Bench-scale cultivation of microalgae scenedesmus almeriensis for CO2 capture and lutein production (2019) Energies, 12 (14), art. no. 2806. DOI: 10.3390/en12142806
- Bioenergy with carbon emissions capture and utilisation towards GHG neutrality: Power-to-Gas storage via hydrothermal gasification (2020) Applied Energy, 280, art. no. 115923. DOI: 10.1016/j.apenergy.2020.115923
- Enhanced hydrogen production from catalytic biomass gasification with in-situ CO2 capture (2020) Environmental Pollution, 267, art. no. 115487. DOI: 10.1016/j.envpol.2020.115487
- Process integration of chemical looping combustion with oxygen uncoupling in a biomass-fired combined heat and power plant (2020) Energy, 210, art. no. 118550. DOI: 10.1016/j.energy.2020.118550
Answer: Thanks for your comments. The authors included sections on CO2 capture in the manuscript, suggested references were also included.
Materials and methods
Please, specify if investigations were carried out in duplicate/triplicate etc.
Please, add standard deviation.
Please, include the elemental analysis of the biomass.
Please, clarify if the assessment of the char, that can be produced after thermal treatment, was carried out.
Answer: Thanks for your comments. The authors included in the manuscript that the analyzes were carried out in triplicate, and the standard deviation was included. The elemental analysis of Sargassum spp. was also included. On the other hand, the assessment of the char, that can be produced after thermal treatment, was not carried out.
Results
Please, improve comparison between your findings and literature data.
Please, include standard deviation.
Please, compare Pelagic Sargassum spp. and fossil fuels in terms of CO2 balance, i.e. CO2 emitted and removed from the atmosphere.
Answer: Thanks for your comments. The authors included more bibliography in the manuscript, and discussed the results obtained. The standard deviation was included. A section was also included in the manuscript on the capture and emission of CO2 from Sargassum spp. and compared with other conventional fuels.
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
The manuscript has been revised and a general improvement can be found. The paper is suitable to be published in this journal in the current form.
