Supply Chain (Re)Design and Pricing for Biomass Ash Valorization as Supplementary Cementitious Materials

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper presents an interesting and valuable study on the pricing and supply chain design for biomass ash valorization as supplementary cementitious materials. The research topic is of great significance in the context of sustainable development, and the methodology is appropriate. However, there are several areas that need improvement.

1. In the introduction, it is necessary to clearly expound several problems to be studied in the article, so as to facilitate the introduction of the article's theme.

2. Besides the existing biomass ashes, there are many other types of wastes that can also be used as supplementary cementitious materials. It is recommended to add a comparative analysis with other alternative options in the paper to highlight the advantages and disadvantages of biomass ashes.

3. It is recommended to further explore how to incorporate uncertainty factors such as the dynamic changes of market demand and the seasonal fluctuations of biomass ash supply into the model, so as to improve the applicability and flexibility of the model.

4. It is suggested to cite more recent high-quality articles in the literature.

5. Future research directions are mentioned in the article, such as considering multiple biomass ashes simultaneously and incorporating uncertainty factors, but the descriptions of these directions are rather general. It is recommended to further refine these research directions, put forward specific research ideas and method frameworks, and provide more operational suggestions for subsequent research.

6. It would be valuable to include a sensitivity analysis to assess how changes in key parameters, such as transportation costs or biomass ash availability, affect the optimal solutions.

7.Figures should be more clear.

 

Comments on the Quality of English Language

(1)polish the language; (2)usually 3-5 keywords.

Author Response

General comment:

This paper presents an interesting and valuable study on the pricing and supply chain design for biomass ash valorization as supplementary cementitious materials. The research topic is of great significance in the context of sustainable development, and the methodology is appropriate. However, there are several areas that need improvement.

Response:

We sincerely thank the reviewer for the positive assessment of our paper's methodology and relevance, as well as for the valuable comments and insights provided in the review. We have prepared a revised version of the manuscript that addresses the remarks.

We want to highlight that following the insightful comments of both reviewers we have: (i) split the introduction into two sections, (ii) improved the mathematical model to include cement plants as possible SCM processing facilities,  (iii) added a complete sensitivity analysis on key aspects of the supply chain, (iv) improved the discussion of the  future research directions, and (v) have a professional proofreading of the paper.

A detailed response to the comments is provided in the attached file. For clarity and easy reference, the modifications and new excerpts have been highlighted in blue within the revised manuscript.

 

 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors,

Thank you for submitting your interesting manuscript. The collection and transportation costs for biomass and its combustion by-products is critical to establishing new value chains for materials often treated as waste.

Your research methodology is clear and well-detailed. My comments focus primarily on the structure and clarity of the manuscript. Specifically, my observations are as follows:

• Page 2, Line 56: Please clarify where the concept of circularity is applied within the described supply chain.
• Page 2, Line 62: Avoid using general terms that might confuse readers, such as "material efficiency" and "waste exchange networks." In this instance, which specific materials and waste streams are you referring to?
• Page 2, Lines 85–87: Simplify certain expressions for better readability. For example, the phrase "Despite the need for a supply chain perspective … considering all stages … their study did not consider other stages of the supply chain..." can be streamlined.
• Page 3, Lines 105–111: This section does not appear to belong to the literature review.
• Page 4, Lines 124–132, and Table 1: This paragraph and Table 1 seem more appropriate at the beginning of the literature discussion.
• Page 4, Lines 152–160: This paragraph also does not align with the literature review's content.
• Page 4, Line 165: Again, there is a reference here that pertains to the study’s methodology.
• General Comment: Dividing the introduction into subsections would improve the organization and presentation of the information.
• Page 7, Lines 276–284: This paragraph would fit better in the introduction.
• Figures Numbering: There is confusion in the numbering of figures: Figures 1 and 2 (Page 6), 3 (Page 7), 3 (Page 15), 6 (Page 17), Figure 6b (?) Line 583 (Page 17), 7 (Page 18), 8 (Page 19). Please revise for consistency.
• Page 15, Lines 508–515: There is an alignment issue in this paragraph.
• Table 5: Since the SCM addition in all four scenarios was 20%, why does the cement use range from 86% to 90% rather than remaining at 80%? Shouldn’t the cement use (%) correspond to the OPC (%) added to concrete?
• Table 5 – Scenario CBA-C: Please confirm whether concrete with OPC + SCM accounts for 63% and concrete with OPC for 37%.
• Table 5: Further discuss the differences in total cost and emissions between scenarios CBA-C and E. These differences are likely linked to the number of processing plants (PPs).
• Transportation Optimization: Have you considered the scenario of transporting SCM to cement plants for mixing with cement there, to reduce transportation costs when concrete plants are located farther from the SCM sources? This approach is employed with fly ash from lignite combustion used by Greek cement industries.
• Pricing Discussion: What are your conclusions regarding the selling price of SCM? In the discussion and conclusions, there is significant emphasis on the supply chain but insufficient exploration of the pricing aspect, which is a crucial component of the algorithm developed.

I hope these suggestions will help refine your manuscript further.

Best regards

Author Response

Reviewer #2 general comment:

 “Thank you for submitting your interesting manuscript. The collection and transportation costs for biomass and its combustion by-products is critical to establishing new value chains for materials often treated as waste. Your research methodology is clear and well-detailed. My comments focus primarily on the structure and clarity of the manuscript. Specifically, my observations are as follows:…”

[detailed remarks]

“I hope these suggestions will help refine your manuscript further.”

 

Response:

We sincerely thank the reviewer for the positive assessment of our paper's methodology and relevance, as well as for the valuable comments and insights provided in the review. The reviewer comments helped us to refine our work contents and structure. We want to particularly thank the reviewer for suggesting us the possibility of processing biomass ash at the cement plants. We have modified the model and data of the case study to incorporate this option. As could be seen in the revised manuscript, this alternative gives very interesting results for the cane bagasse ash supply chain.

Additionally, we want to highlight that following the insightful comments of both reviewers we have: (i) split the introduction into two sections, (ii) improved the mathematical model to include cement plants as possible SCM processing facilities,  (iii) added a complete sensitivity analysis on key aspects of the supply chain, (iv) improved the discussion of the  future research directions, and (v) have a professional proofreading of the paper. (v) added new information, discussion and conclusions regarding the biomass ash pricing mechanism.

We have prepared a revised version of the manuscript that addresses the remarks. A detailed response to the comments is provided in an attached file. For clarity and easy reference, the modifications and new excerpts have been highlighted in blue within the revised manuscript

Author Response File: Author Response.pdf