Techno-Economic Assessment of Amine-Based Carbon Capture in Waste-to-Energy Incineration Plant Retrofit

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

 

The article is devoted to the consideration of economic recommendations for the release of CO2 as a product for waste processing plants. Despite the higher costs, reducing CO2 emissions and obtaining it as a commercial product is a actual topic. In large industrial production that requires CO2 as a source, similar technologies are widely used. This article discusses the economic component of CO2 absorption technology for small industries. This topic is relevant, although it requires detailed consideration, for example, the quality of the resulting co2, etc.

 

This article may be published after changes are made:

Line 108 et seq. The links to tables and figures are provided incorrectly.

Line 111 Tabella typo (Italian)

Figure 2 It is necessary to show the characteristics of the flows (temperatures, flow rates, compositions of the main components). Is it possible to use the heat from flue gases for the MEA return heater in the E-204 reboiler?

Line 205. It is necessary to provide ΔG values (if it is possible).

Line 231 Why is the absorbent flow rate of 1.2∙𝐿𝑚𝑖𝑛 chosen? Has cost optimization been carried out to minimize capital and economic costs?

Line 238 It is necessary to explain why the pressure in the C-202 stripper was selected at 1.8 bar. Indeed, as the pressure decreases, desorption proceeds better and the liquid will boil at a lower temperature.

Lines 302 303 𝑓 𝑇𝑜𝑡𝑎𝑙,𝐶𝑆 and 𝐹 𝑇𝑜𝑡𝑎𝑙,𝐶𝑆 . Uniformity in notation is necessary.

Comments on the Quality of English Language

check italian wors

Author Response

Rebuttal of the Manuscript: “Techno-economic assessment of amine-based carbon capture in Waste-to-Energy incineration plant retrofit.”

 

Michele Bertone, Luca Stabile, Gino Cortellessa, Fausto Arpino and Giorgio Buonanno.

 

We sincerely thank the reviewer for the thorough review and valuable comments on our manuscript. In response, we have carefully considered each comment and have accordingly made substantive modifications to our manuscript. Below, we provide a detailed point-by-point response to the reviewer’s comments, including references to the specific changes made in the revision. It is our hope that these revisions adequately address the concerns raised and that our manuscript is now deemed suitable for publication in the journal Sustainability.

 

The article is devoted to the consideration of economic recommendations for the release of CO₂ as a product for waste processing plants. Despite the higher costs, reducing CO₂ emissions and obtaining it as a commercial product is a actual topic. In large industrial production that requires CO₂ as a source, similar technologies are widely used. This article discusses the economic component of CO₂ absorption technology for small industries. This topic is relevant, although it requires detailed consideration, for example, the quality of the resulting CO₂, etc.

 

This article may be published after changes are made:

 

• Comment 1: Line 108 et seq. The links to tables and figures are provided incorrectly.
• Response: The manuscript has been revised to correct the links to tables and figures. All references now accurately point to the appropriate tables and figures.

 

• Comment 2: Line 111 Tabella typo (Italian).
• Response: The Italian term "Tabella" has been corrected to "Table" throughout the document.

 

• Comment 3: Figure 2 It is necessary to show the characteristics of the flows (temperatures, flow rates, compositions of the main components). Is it possible to use the heat from flue gases for the MEA return heater in the E-204 reboiler?
• Response: The characteristics of the flows, including temperatures, flow rates, and compositions, have been incorporated into Table 2 and further detailed in Section 2.3 of the manuscript. Regarding the use of flue gas heat for the MEA return in the E-204 reboiler, this suggestion offers significant potential for future work.

 

• Comment 4: Line 205. It is necessary to provide ΔG values (if it is possible).
• Response: The ΔG values used in the reaction model are default values from the software, which relies on specific databases.

 

• Comment 5: Line 231 Why is the absorbent flow rate of 1.2∙???? chosen? Has cost optimization been carried out to minimize capital and economic costs?
• Response: The absorbent flow rate of  was selected primarily to ensure the absence of isothermal zones within the absorber, which is critical for maintaining uniform CO₂ absorption efficiency across the column. This rate ensures optimal interaction between the CO₂ vapor and the MEA solvent, thereby ensuring that all areas of the column are working properly. The choice of this specific flow rate was driven by technical considerations rather than cost optimization. Indeed, no cost analysis was performed at this stage.

 

• Comment 6: Line 238 It is necessary to explain why the pressure in the C-202 stripper was selected at 1.8 bar. Indeed, as the pressure decreases, desorption proceeds better and the liquid will boil at a lower temperature.
• Response: The manuscript now includes a detailed explanation of the choice of the 1.8 bar pressure setting for the stripper (C-202): "In typical operations, the stripper is set to a pressure above atmospheric levels. This approach is supported by the fact that the heat absorbed by CO2 in MEA is nearly double that required for the vaporization of water. According to the Clausius-Clapeyron equation, the vapor pressure of CO2 increases more rapidly than that of water, requiring a higher operational pressure in the stripper compared to the absorber to achieve temperatures that are favorable for the selective transfer of CO2 over water. Nevertheless, the pressure is influenced by the degradation temperature of MEA, that must not exceed 110°C in the reboiler to prevent solvent degradation. Therefore, it is crucial to set the column pressure at the highest possible level that still ensures the solvent’s boiling point remains below its degradation temperature. For a 30 wt% MEA solution, this optimal pressure has been determined to be 1.8 bar, which has been accordingly established for the stripper’s operation."

 

• Comment 7: Lines 302 303 ? ?????,?? and ? ?????,?? . Uniformity in notation is necessary.
• Response: The corrected notation is now applied.

 

We hope that all the referee’s comments have been well addressed through the modifications made to the paper.

 

Kind regards,

Michele Bertone

 

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript has focused to determine the technical and economic feasibility of a small-scale Carbon Capture system for various sizes. propose this article for publication after the following changes are made:

1. Please correct the chemical formulas, in the text it appear misspelled: ex. CO2.

2. Please correct the automatically citation of the table and figures in the text (it appear like Error! Reference source not found_).

3. Row 111 – Table 1 – was write in Italian language “tabella 1”.

4. All the results obtained must be sustained by other authors results. The discussion should include a comparison of the numerical values of the results obtained by you with the works of other authors; The provided just 4 references in the section Results and Discussions

Author Response

Rebuttal of the Manuscript: “Techno-economic assessment of amine-based carbon capture in Waste-to-Energy incineration plant retrofit.”

 

Michele Bertone, Luca Stabile, Gino Cortellessa, Fausto Arpino and Giorgio Buonanno.

 

We sincerely thank the reviewer for the thorough review and valuable comments on our manuscript. In response, we have carefully considered each comment and have accordingly made substantive modifications to our manuscript. Below, we provide a detailed point-by-point response to the reviewer’s comments, including references to the specific changes made in the revision. It is our hope that these revisions adequately address the concerns raised and that our manuscript is now deemed suitable for publication in the journal Sustainability.

 

The manuscript has focused to determine the technical and economic feasibility of a small-scale Carbon Capture system for various sizes. propose this article for publication after the following changes are made:

 

• Comment 1: Please correct the chemical formulas, in the text it appear misspelled: ex. CO2.
• Response: All sentences with CO₂ have been corrected throughout the manuscript.

 

• Comment 2: Please correct the automatically citation of the table and figures in the text (it appear like Error! Reference source not found_).
• Response: All the issues related to the citation of tables and figures have been corrected. Each reference is now correctly linked.

 

• Comment 3: Row 111 – Table 1 – was write in Italian language “tabella 1”.
• Response: The manuscript has been revised to ensure that all content is presented in English. The specific reference to “Tabella 1” has been corrected to “Table 1”.

 

• Comment 4: Line 205. It is necessary to provide ΔG values (if it is possible).
• Response: The ΔG values referenced are default values from the software’s database.

 

• Comment 5: All the results obtained must be sustained by other authors results. The discussion should include a comparison of the numerical values of the results obtained by you with the works of other authors; The provided just 4 references in the section Results and Discussions.
• Response: The section on results has been expanded to provide a more detailed discussion. However, a direct numerical comparison with other studies is challenging due to the nature of cost estimation for capture systems, which varies significantly based on assumptions such as plant size, the components considered in the system, whether the estimation considered only the capture or also includes conditioning and transportation, the concentration of CO2 in flue gases, and many other parameters. These complexities make it difficult to directly compare numerical values across different studies without considering the underlying assumptions that significantly influence the outcomes.

 

We hope that all the referee’s comments have been well addressed through the modifications made to the paper.

 

Kind regards,

Michele Bertone

Reviewer 3 Report

Comments and Suggestions for Authors

Overall, a well-written manuscript with no major flaws. Minor issues were listed above for the authors. It is an interesting and popular topic. It will be of interest to the readers. 

Pay attention on subscript, especially in Abstract section (CO2). Also check all Manuscript.

The introduction is written very well overall; however, more summaries of previously published studies in similar areas could increase its value. 

L108-109, 127, 139...etc Error! Refference Source not found! Check all Manuscript and correct it

Poor discussion on the results. The authors should compare their own results with those of other similar research. Only in this way is it possible to indicate the added value for this investigation.

 

Author Response

Rebuttal of the Manuscript: “Techno-economic assessment of amine-based carbon capture in Waste-to-Energy incineration plant retrofit.”

 

Michele Bertone, Luca Stabile, Gino Cortellessa, Fausto Arpino and Giorgio Buonanno.

 

We sincerely thank the reviewer for the thorough review and valuable comments on our manuscript. In response, we have carefully considered each comment and have accordingly made substantive modifications to our manuscript. Below, we provide a detailed point-by-point response to the reviewer’s comments, including references to the specific changes made in the revision. It is our hope that these revisions adequately address the concerns raised and that our manuscript is now deemed suitable for publication in the journal Sustainability.

 

Overall, a well-written manuscript with no major flaws. Minor issues were listed above for the authors. It is an interesting and popular topic. It will be of interest to the readers.

 

• Comment: Pay attention on subscript, especially in Abstract section (CO2). Also check all Manuscript.
• Response: The entire manuscript has been carefully reviewed, and all "CO2" have been corrected throughout the document.

 

• Comment 2: The introduction is written very well overall; however, more summaries of previously published studies in similar areas could increase its value.
• Response: The introduction has been extended by incorporating more comprehensive summaries of previously published studies in the area of carbon capture in WtE systems.

 

• Comment 3: L108-109, 127, 139...etc Error! Refference Source not found! Check all Manuscript and correct it.
• Response: All sentences where the source references were not found have been corrected.

 

• Comment 4: Poor discussion on the results. The authors should compare their own results with those of other similar research. Only in this way is it possible to indicate the added value for this investigation.
• Response: The results section has been expanded to provide a more detailed discussion. However, a direct numerical comparison with other studies is challenging due to the nature of cost estimation for capture systems, which varies significantly based on assumptions such as plant size, the components considered in the system, whether the estimation considered only the capture or also includes conditioning and transportation, the concentration of CO₂ in flue gases, and many other parameters. These complexities make it difficult to directly compare numerical values across different studies without considering the underlying assumptions that significantly influence the outcomes.

 

We hope that all the referee’s comments have been well addressed through the modifications made to the paper.

 

Kind regards,

Michele Bertone