Life Cycle Assessment and Economic Analysis of an Innovative Biogas Membrane Reformer for Hydrogen Production
, Xun Liao 2, Arnaud Dauriat 2, Marco Binotti 1 and Giampaolo Manzolini 1Round 1
Reviewer 1 Report
In this manuscript, authors discussed life cycle assessment and economy of membrane reformer for H2 production. The work is well organized and written. This paper could be published in Processes, but only after clarification.
1. In this study, authors examined possibility of membrane reformer for hydrogen production. But, the reviewer could not find membrane specification, including permeability and separation performances. Those informations were important for readers.
2. Additionally, authors calculated membrane reformer process at 550-600oC. The reactor condition is severe for membranes. Thus, the reviewer think that it is important to add introductions about development of separation membrane itself for hydrogen production.
3. Please correct subscripts, such as H”2”.
Author Response
In this manuscript, authors discussed life cycle assessment and economy of membrane reformer for H2 production. The work is well organized and written. This paper could be published in Processes, but only after clarification.
In this study, authors examined possibility of membrane reformer for hydrogen production. But, the reviewer could not find membrane specification, including permeability and separation performances. Those informations were important for readers.
Membrane reactor information were included in Annex 7.2. The sentence “The scheme of the membrane reactor model and the main membrane features are summarised in Annex 7.2.” was added in the manuscript.
Additionally, authors calculated membrane reformer process at 550-600°C. The reactor condition is severe for membranes. Thus, the reviewer think that it is important to add introductions about development of separation membrane itself for hydrogen production.
The authors are aware of the high temperature issues related to the membrane reactors as discussed in previous works. We covered this aspect by assessing the system performance at 550°C in addition to the 600°C. We prefer not to debate too much about this point in the work so to keep the focus on LCA.
Please correct subscripts, such as H”2”.
Subscripts were corrected.
Reviewer 2 Report
In the submitted work, the authors have carried out an LCA analysis for hydrogen production from Biogas using membrane reactors. While the topic is worthy of investigation and the content of the manuscript is satisfactorily detailed, the overall presentation of the manuscript needs to be improved significantly. Improper sentence constructions at several places in the manuscript make it difficult to understand the content.
Some specific suggestions/corrections are mentioned below:
1) Line 46: ‘PSA’ should appear before ‘unit’
2) ‘ATR-CMR’ is not mentioned in Figure 1. What does ‘C’ stand for in ‘ATR-CMR’?
3) Line 50: ‘volumes’ of what?
4) Line 52: Make it explicit what the innovation is? Is the usage of membrane reactor the innovation or the usage of palladium reactor?
5) Line 69: ‘key determining factors’ for what?
6) Change ‘H2’ to H2’
7) For a comprehensive presentation and to enable reproduction of results, provide the following in the appendix:
a. Geometric details of the equipment/process units
b. Process flowsheets with optimal operating conditions for reference and BIONIC system. Specify temperature, pressure and compositions of the major streams
c. Key process parameters utilized in process simulations, such as PSA recovery, heat transfer coefficients
8) Line 145: Give appropriate reference for LHVH2
9) Line 146: How is the value of 45% obtained?
10) Table 2: Clarify that LF is Landfill and AD is Anaerobic Digestion
11) Table 3: Are the efficiency values for reference systems consistent with those reported in literature? For example, Kumar et al. in ‘Multi-resolution model of an industrial hydrogen plant for plant-wide operational optimization with non-uniform steam-methane reformer temperature field’ report a value of ~74 for thermal efficiency. Please explain this substantial difference with appropriate literature references.
12) Line 163: What does ‘L’ in LCOH stand for?
13) Line 166: What is Carrying Charge Factor? Provide proper reference.
14) Line 167: How are the figures of 65% and 80% obtained? Provide proper references.
15) Lines 210-211: It is not clear how the values 39%/46% are ‘aligned’ with 75-90% efficiencies.
16) Figure 6 needs to be enlarged
17) Legends are missing figures 7 & 8
18) Lines 287-290: ‘Investigation of permeate side configuration’ is not provided in the submitted manuscript.
19) Typos/rephrase
a. Line 40: potential alternative for what?
b. Line 63: ‘et al.’
Author Response
Some specific suggestions/corrections are mentioned below:
1. Line 46: ‘PSA’ should appear before ‘unit’
It was corrected.
2. ‘ATR-CMR’ is not mentioned in Figure 1. What does ‘C’ stand for in ‘ATR-CMR’?
ATR-CMR was mentioned in Figure 1. CMR was added in the nomenclature. ATR-CMR acronym was introduced in the manuscript in section 1.
3. Line 50: ‘volumes’ of what?
The word ‘Volumes’ was replaced with ‘equipment size’.
4. Make it explicit what the innovation is? Is the usage of membrane reactor the innovation or the usage of palladium reactor?
The following sentence was modified to The innovative membrane reactor technology, such as the autothermal catalytic membrane reactor (ATR-CMR) in Figure 1 developed within the BIONICO, allows the production and separation of hydrogen in a single vessel, with advantages over traditional biogas reforming related to the increase of the overall conversion efficiency and to the strong decrease of equipment size due to the process intensification [6].
5. Line 69: ‘key determining factors’ for what?
The term ‘for LCA’ was added in the text.
6. Change ‘H2’ to H2’
Subscripts were corrected.
7. For a comprehensive presentation and to enable reproduction of results, provide the following in the appendix:
a. Geometric details of the equipment/process units
b. Process flowsheets with optimal operating conditions for reference and BIONIC system. Specify temperature, pressure and compositions of the major streams
c. Key process parameters utilized in process simulations, such as PSA recovery, heat transfer coefficients
The authors already presented all the required data by the reviewer in previous works that are open access. We prefer to limit the additional information so to keep the focus on LCA analysis, as well as to limit overlapping with previous works (so to prevent plagiarism and this type of issue). Several sentences in the manuscript refer to the previous works:
a. The methodology adopted is consistent with previous works [8,17]. A phenomenological model of membrane reactor developed in Aspen Custom Modeler® (ACM) was adopted [18].
b. Table 3 summarizes the thermodynamic and economic results for the two biogas compositions with the highest efficiency [7,8]
c. The complete methodology and the detailed components costs are reported in [7,8].
d. Results are also compared with values found for conventional hydrogen production systems from [7].
8. Line 145: Give appropriate reference for LHVH2
A footnote with appropriate reference was added in the manuscript.
9. Line 146: How is the value of 45% obtained?
The value 45% was obtained from https://www.eea.europa.eu/data-and-maps/indicators/overview-of-the-electricity-production-2/assessment-4. A footnote with appropriate reference was added in the manuscript.
10. Table 2: Clarify that LF is Landfill and AD is Anaerobic Digestion
Acronyms of landfill and anaerobic digestion were introduced in the manuscript at the beginning of section 2.
11. Table 3: Are the efficiency values for reference systems consistent with those reported in literature? For example, Kumar et al. in ‘Multi-resolution model of an industrial hydrogen plant for plant-wide operational optimization with non-uniform steam-methane reformer temperature field’ report a value of ~74 for thermal efficiency. Please explain this substantial difference with appropriate literature references.
The suggested paper for the comparison is not consistent with the paper’s topic. In this work, the authors describes a small hydrogen production plant from biogas (maximum CH4 content of about 60%) while the paper of Kumar et al. discusses about an industrial plant that produce hydrogen from natural gas (CH4 content of about 95%). The papers used as reference in this manuscript are related to hydrogen production from biogas, otherwise the comparison is not fair.
12. Line 163: What does ‘L’ in LCOH stand for?
"L" stands for levelised. The acronym LCOH was added in the nomenclature and in line 174 of the revised manuscript.
13. Line 166: What is Carrying Charge Factor? Provide proper reference.
Reference [19] (K. Gerdes, W.M. Summers, J. Wimer, Cost Estimation Methodology for NETL Assessments of Power Plant Performance DOE/NETL-2011/1455, (2011) 26) was added in the sentences: “The total plant cost (TPC) is calculated with a bottom-up approach breaking down the power plant into basic components or equipment, and then adding installation costs, indirect costs and owner’s and contingencies costs [19].” and “where CCF represents the Carrying Charge Factor [19]”. Moreover CCF was included in the nomenclature.
14. Line 167: How are the figures of 65% and 80% obtained? Provide proper references.
References [20,21] were added in the manuscript. [20] V. Spallina, D. Pandolfo, A. Battistella, M.C. Romano, M. Van Sint Annaland, F. Gallucci, Techno-economic assessment of membrane assisted fluidized bed reactors for pure H 2 production with CO 2 capture, Energy Convers. Manag. 120 (2016) 257–273. doi:10.1016/j.enconman.2016.04.073. [21] G. Manzolini, E. Macchi, M. Gazzani, CO2 capture in natural gas combined cycle with SEWGS. Part B: Economic assessment, Int. J. Greenh. Gas Control. 12 (2013) 502–509. doi:10.1016/j.ijggc.2012.06.021.
15. Lines 210-211: It is not clear how the values 39%/46% are ‘aligned’ with 75-90% efficiencies.
Sentence was modified: “The electric and heat efficiencies are assumed to be 39% and 46%, respectively, with a total CHP efficiency of 85%”
16. Figure 6 needs to be enlarged
Figure 6 was enlarged
17. Legends are missing figures 7 & 8
Missing legends were added.
18. Lines 287-290: ‘Investigation of permeate side configuration’ is not provided in the submitted manuscript.
Sentence about permeate side configuration was removed.
19. Typos/rephrase
a. Line 40: potential alternative for what?
The sentence was modified: ”In Europe, the common biogas production process is the anaerobic digestion of agricultural waste, manure, and energy crops; then biogas, or biomethane (if the plant has an upgrading step), is currently fed to Internal combustion engine for electricity and heat production [4]”.
b. Line 63: ‘et al.’
It was corrected
Reviewer 3 Report
The topic is interesting, the work is well done and the results will be useful. Writting and presentation are adequate in general. The only point to improve is to use larger letter size in several figures (Fig 6 and Fig 10), because otherwise they would be not useful for the readers.
I assume no cost is considered for biogas, but this should be stated.
Author Response
The topic is interesting, the work is well done and the results will be useful. Writting and presentation are adequate in general. The only point to improve is to use larger letter size in several figures (Fig 6 and Fig 10), because otherwise they would be not useful for the readers.
Figures 6 and 10 were improved.
I assume no cost is considered for biogas, but this should be stated.
Biogas production cost is considered as stated in the sentence: “Fixed O&M costs are represented by maintenance, insurance and operators costs, while variable O&M costs consider consumables such as catalyst, biogas [22], process water, membranes and auxiliaries electric energy consumptions [23].”
Round 2
Reviewer 1 Report
The authors were presented with a set of corrections, and questions from the reviewer. I think that authors have responded adequately to all of them. I recommend publication of the current version.
Reviewer 2 Report
The authors have satisfactorily responded to my previous comments. I recommend publication of the manuscript.
