Impact of Implementing Circular Waste Management System and Energy Recovery in a City with 100,000 Inhabitants on Nitrogen Emissions by 2035

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This article focuses on MSW mass and nitrogen flow in Polish circulating municipal waste management system. STAN model is used to develop the mass flow analysis of waste and nitrogen in waste management system. The nitrogen emissions of four biodegradable waste treatment technologies (CB, ADB+AS, COF, and ADOF+AS) are discussed, and the key points of each scheme are given.

However, the manuscript contains several weaknesses in its current form. The following points should be revised appropriately.

1. In the Abstract section, the environmental benefits of waste treatment options should be highlighted more prominently. In addition, it should also indicate the research results or conclusions. Data should be provided to increase the credibility of the study.

2. Four kinds of biodegradable waste treatment technologies should added in the Introduction section.

3. In the Introduction section, please indicate how to quantify the amount of municipal waste and nitrogen flow, that is, clarify the methods used. At the same time, what is the contribution of the article.

4. Some concepts in the manuscript are difficult to understand, such as what is selectively collected waste; what is MBP in Figure 3? If necessary, it can be summarized in the appendix or supporting materials.

5. Where does the formula in line 112 come from? Give the references.

6. There are some mistakes in the article that need to be corrected: Line 225, should be Figure 3. Line 371, where is Figure 11.

7. Lines 63-68 seem unable to connect with the context.

8. In Table 2, please explain how these ratio values were obtained.

Author Response

"Please see the attachment"

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

The theme of the report is fully in line with the theme of the special issue. The presented results are interesting and have a place in the journal Energies. The paper looks well structured, clear, and complete (includes: abstract; introduction, Materials and Methods, Results, Discussion; illustrations; tables with results; conclusions, and reference list). The article fits into the literature and field, and it advances the knowledge of the subject. However, there are some questions, which could be addressed:

·         The objectives of the study are not very clearly defined and more precisely the novelty in the development is not highlighted.

·         An abstract can be expanded up to 250 words to emphasize novelty as in the main text. The first two sentences of the abstract are very general. They would be appropriate in the introduction part. Instead, authors should point out what makes their research unique.

·         In the text of the article, the authors used a period (.) to separate the decimal point of the numbers, but unfortunately in the presented tables, they used a comma (,) instead of a period.

·         In Fig. 1 part of the text of one of the frames goes outside it. This can be corrected.

·         In fig. 2 presents a complex scheme with mass flows of waste and nitrogen in the waste management system for different periods. However, for a wider range of readers, this scheme deserves at least a brief explanation.

·         The analysis of the listed scenarios should be more in-depth and accessible to a wider range of readers of the journal. In the title to drop by 2035. It was not quite clear to me why exactly the analysis is until 2035 and not, for example, until 2050. I assume that the source [3] that the authors used in their research captured data only up to the year 3035.

·         The authors have devoted a lot of attention and volume to the figures, and considerably less to the discussions and analyses.

 

·         The English language could also be improved (use of the full article in some cases) and some typos avoided. Otherwise, the text is understandable.

Comments on the Quality of English Language

The English language could also be improved (use of the full article in some cases) and some typos avoided. Otherwise, the text is understandable.

Author Response

"Please see the attachment"

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

Peer Review Report

Peer review report on ‘Impact of implementing circular waste management system and energy recovery in a city with 100,000 inhabitants on nitrogen emissions by 2035’

 

1. Original Submission

Recommendation: Major revision

 

2. Comments to Author:

Manuscript Ref. No.: energies-2758660

Title: Impact of implementing circular waste management system and energy recovery in a city with 100,000 inhabitants on nitrogen emissions by 2035

Article Type: Original article

Overview and general recommendation:

The scope of the study was to estimate the volume of nitrogen emissions from municipal waste treatment facilities in a city with a population of 100,000 in 2020, with an eye toward 2035. The study examined 4 different biodegradable waste treatment technologies: aerobic and anaerobic stabilization for the organic part of municipal solid waste, and composting and methane digestion for bio-waste. This paper provides important insight into circular waste management system.

However, several improvements are necessary before this manuscript can be published.

This original article meets the criteria for publication in Energies Journal.

 

Comments:

Q1. Please rewrite the Abstract. Without adding any unnecessary details to divert readers' attention, the Abstract should give them all the information they require to comprehend the study's purpose: introduction, methodology, results, and conclusion.

Q1. Introduction: Please highlight the scientific gap and the contribution of this study in the Introduction.

Q2. Method, Table 3: Please explain in detail the reasons you chose the specific adopted parameters for the calculations (line 3, 6, and 8 of Table 3). Explain why you choose the value 0.2 m³/Mg for the amount of sewage, 350 gN/m³, 0.070, … 800 gN/m³,. …, 0.025 kgN/Mg, etc.   

Q3. Please add more discussion and literature references of other similar studies in Discussion section.   

Q4. Please rewrite the Conclusion section and explain the abbreviations OFMSW, ADB+AS - ADOF+AS, ADB+AS - 380 COF, MBT etc. in order Conclusion section to stand alone.

 

Author Response

"Please see the attachment"

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

It's OK!

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have satisfactorily addressed most of my concerns.